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//==========================================================================

//

//      src/sys/netinet/if_ether.c

//

//==========================================================================

//####BSDCOPYRIGHTBEGIN####

//

// -------------------------------------------

//

// Portions of this software may have been derived from OpenBSD, 

// FreeBSD or other sources, and are covered by the appropriate

// copyright disclaimers included herein.

//

// Portions created by Red Hat are

// Copyright (C) 2002 Red Hat, Inc. All Rights Reserved.

//

// -------------------------------------------

//

//####BSDCOPYRIGHTEND####

//==========================================================================

/*

 * Copyright (c) 1982, 1986, 1988, 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.

 *

 *      @(#)if_ether.c  8.1 (Berkeley) 6/10/93

 * $FreeBSD: src/sys/netinet/if_ether.c,v 1.64.2.11 2001/07/25 17:27:56 jlemon Exp $

 */

/*

 * Ethernet address resolution protocol.

 * TODO:

 *      add "inuse/lock" bit (or ref. count) along with valid bit

 */

#include <sys/param.h>

#include <sys/queue.h>

#include <sys/mbuf.h>

#include <sys/malloc.h>

#include <sys/socket.h>

#include <net/if.h>

#include <net/if_dl.h>

#include <net/if_types.h>

#include <net/route.h>

#include <net/netisr.h>

#include <net/if_llc.h>

#ifdef BRIDGE

#include <net/ethernet.h>

#include <net/bridge.h>

#endif

#include <netinet/in.h>

#include <netinet/in_var.h>

#include <netinet/if_ether.h>

#include <net/iso88025.h>

#define SIN(s) ((struct sockaddr_in *)s)

#define SDL(s) ((struct sockaddr_dl *)s)

/* timer values */

static int arpt_prune = (5*60*1); /* walk list every 5 minutes */

static int arpt_keep = (20*60); /* once resolved, good for 20 more minutes */

static int arpt_down = 20;      /* once declared down, don't send for 20 sec */

#define rt_expire rt_rmx.rmx_expire

struct llinfo_arp {

        LIST_ENTRY(llinfo_arp) la_le;

        struct  rtentry *la_rt;

        struct  mbuf *la_hold;          /* last packet until resolved/timeout */

        long    la_asked;               /* last time we QUERIED for this addr */

#define la_timer la_rt->rt_rmx.rmx_expire /* deletion time in seconds */

};

static  LIST_HEAD(, llinfo_arp) llinfo_arp;

struct  ifqueue arpintrq = {0, 0, 0, 50};

static int      arp_inuse, arp_allocated;

static int      arp_maxtries = 5;

static int      useloopback = 1; /* use loopback interface for local traffic */

static int      arp_proxyall = 0;

static void     arp_rtrequest __P((int, struct rtentry *, struct sockaddr *));

static void     arprequest __P((struct arpcom *,

                        struct in_addr *, struct in_addr *, u_char *));

static void     arpintr __P((void));

static void     arptfree __P((struct llinfo_arp *));

static void     arptimer __P((void *));

static struct llinfo_arp

                *arplookup __P((u_long, int, int));

#ifdef INET

static void     in_arpinput __P((struct mbuf *));

#endif

/*

 * Timeout routine.  Age arp_tab entries periodically.

 */

/* ARGSUSED */

static void

arptimer(ignored_arg)

        void *ignored_arg;

{

        int s = splnet();

        register struct llinfo_arp *la = llinfo_arp.lh_first;

        struct llinfo_arp *ola;

        timeout(arptimer, (caddr_t)0, arpt_prune * hz);

        while ((ola = la) != 0) {

                register struct rtentry *rt = la->la_rt;

                la = la->la_le.le_next;

                if (rt->rt_expire && rt->rt_expire <= time_second)

                        arptfree(ola); /* timer has expired, clear */

        }

        splx(s);

}

/*

 * Parallel to llc_rtrequest.

 */

static void

arp_rtrequest(req, rt, sa)

        int req;

        register struct rtentry *rt;

        struct sockaddr *sa;

{

        register struct sockaddr *gate = rt->rt_gateway;

        register struct llinfo_arp *la = (struct llinfo_arp *)rt->rt_llinfo;

        static struct sockaddr_dl null_sdl = {sizeof(null_sdl), AF_LINK};

        static int arpinit_done;

        if (!arpinit_done) {

                arpinit_done = 1;

                LIST_INIT(&llinfo_arp);

                timeout(arptimer, (caddr_t)0, hz);

                register_netisr(NETISR_ARP, arpintr);

        }

        if (rt->rt_flags & RTF_GATEWAY)

                return;

        switch (req) {

        case RTM_ADD:

                /*

                 * XXX: If this is a manually added route to interface

                 * such as older version of routed or gated might provide,

                 * restore cloning bit.

                 */

                if ((rt->rt_flags & RTF_HOST) == 0 &&

                    SIN(rt_mask(rt))->sin_addr.s_addr != 0xffffffff)

                        rt->rt_flags |= RTF_CLONING;

                if (rt->rt_flags & RTF_CLONING) {

                        /*

                         * Case 1: This route should come from a route to iface.

                         */

                        rt_setgate(rt, rt_key(rt),

                                        (struct sockaddr *)&null_sdl);

                        gate = rt->rt_gateway;

                        SDL(gate)->sdl_type = rt->rt_ifp->if_type;

                        SDL(gate)->sdl_index = rt->rt_ifp->if_index;

                        rt->rt_expire = time_second;

                        break;

                }

                /* Announce a new entry if requested. */

                if (rt->rt_flags & RTF_ANNOUNCE)

                        arprequest((struct arpcom *)rt->rt_ifp,

                            &SIN(rt_key(rt))->sin_addr,

                            &SIN(rt_key(rt))->sin_addr,

                            (u_char *)LLADDR(SDL(gate)));

                /*FALLTHROUGH*/

        case RTM_RESOLVE:

                if (gate->sa_family != AF_LINK ||

                    gate->sa_len < sizeof(null_sdl)) {

                        log(LOG_DEBUG, "arp_rtrequest: bad gateway value\n");

                        break;

                }

                SDL(gate)->sdl_type = rt->rt_ifp->if_type;

                SDL(gate)->sdl_index = rt->rt_ifp->if_index;

                if (la != 0)

                        break; /* This happens on a route change */

                /*

                 * Case 2:  This route may come from cloning, or a manual route

                 * add with a LL address.

                 */

                R_Malloc(la, struct llinfo_arp *, sizeof(*la));

                rt->rt_llinfo = (caddr_t)la;

                if (la == 0) {

                        log(LOG_DEBUG, "arp_rtrequest: malloc failed\n");

                        break;

                }

                arp_inuse++, arp_allocated++;

                Bzero(la, sizeof(*la));

                la->la_rt = rt;

                rt->rt_flags |= RTF_LLINFO;

                LIST_INSERT_HEAD(&llinfo_arp, la, la_le);

#ifdef INET

                /*

                 * This keeps the multicast addresses from showing up

                 * in `arp -a' listings as unresolved.  It's not actually

                 * functional.  Then the same for broadcast.

                 */

                if (IN_MULTICAST(ntohl(SIN(rt_key(rt))->sin_addr.s_addr))) {

                        ETHER_MAP_IP_MULTICAST(&SIN(rt_key(rt))->sin_addr,

                                               LLADDR(SDL(gate)));

                        SDL(gate)->sdl_alen = 6;

                        rt->rt_expire = 0;

                }

                if (in_broadcast(SIN(rt_key(rt))->sin_addr, rt->rt_ifp)) {

                        memcpy(LLADDR(SDL(gate)), etherbroadcastaddr, 6);

                        SDL(gate)->sdl_alen = 6;

                        rt->rt_expire = 0;

                }

#endif

                if (SIN(rt_key(rt))->sin_addr.s_addr ==

                    (IA_SIN(rt->rt_ifa))->sin_addr.s_addr) {

                    /*

                     * This test used to be

                     *  if (loif.if_flags & IFF_UP)

                     * It allowed local traffic to be forced

                     * through the hardware by configuring the loopback down.

                     * However, it causes problems during network configuration

                     * for boards that can't receive packets they send.

                     * It is now necessary to clear "useloopback" and remove

                     * the route to force traffic out to the hardware.

                     */

                        rt->rt_expire = 0;

                        Bcopy(((struct arpcom *)rt->rt_ifp)->ac_enaddr,

                                LLADDR(SDL(gate)), SDL(gate)->sdl_alen = 6);

                        if (useloopback)

                                rt->rt_ifp = loif;

                }

                break;

        case RTM_DELETE:

                if (la == 0)

                        break;

                arp_inuse--;

                LIST_REMOVE(la, la_le);

                rt->rt_llinfo = 0;

                rt->rt_flags &= ~RTF_LLINFO;

                if (la->la_hold)

                        m_freem(la->la_hold);

                Free((caddr_t)la);

        }

}

/*

 * Broadcast an ARP request. Caller specifies:

 *      - arp header source ip address

 *      - arp header target ip address

 *      - arp header source ethernet address

 */

static void

arprequest(ac, sip, tip, enaddr)

        register struct arpcom *ac;

        register struct in_addr *sip, *tip;

        register u_char *enaddr;

{

        register struct mbuf *m;

        register struct ether_header *eh;

        register struct ether_arp *ea;

        struct sockaddr sa;

        static u_char   llcx[] = { 0x82, 0x40, LLC_SNAP_LSAP, LLC_SNAP_LSAP,

                                   LLC_UI, 0x00, 0x00, 0x00, 0x08, 0x06 };

        if ((m = m_gethdr(M_DONTWAIT, MT_DATA)) == NULL)

                return;

        m->m_pkthdr.rcvif = (struct ifnet *)0;

        switch (ac->ac_if.if_type) {

        case IFT_ISO88025:

                m->m_len = sizeof(*ea) + sizeof(llcx);

                m->m_pkthdr.len = sizeof(*ea) + sizeof(llcx);

                MH_ALIGN(m, sizeof(*ea) + sizeof(llcx));

                (void)memcpy(mtod(m, caddr_t), llcx, sizeof(llcx));

                (void)memcpy(sa.sa_data, etherbroadcastaddr, 6);

                (void)memcpy(sa.sa_data + 6, enaddr, 6);

                sa.sa_data[6] |= TR_RII;

                sa.sa_data[12] = TR_AC;

                sa.sa_data[13] = TR_LLC_FRAME;

                ea = (struct ether_arp *)(mtod(m, char *) + sizeof(llcx));

                bzero((caddr_t)ea, sizeof (*ea));

                ea->arp_hrd = htons(ARPHRD_IEEE802);

                break;

        case IFT_FDDI:

        case IFT_ETHER:

                /*

                 * This may not be correct for types not explicitly

                 * listed, but this is our best guess

                 */

        default:

                m->m_len = sizeof(*ea);

                m->m_pkthdr.len = sizeof(*ea);

                MH_ALIGN(m, sizeof(*ea));

                ea = mtod(m, struct ether_arp *);

                eh = (struct ether_header *)sa.sa_data;

                bzero((caddr_t)ea, sizeof (*ea));

                /* if_output will not swap */

                eh->ether_type = htons(ETHERTYPE_ARP);

                (void)memcpy(eh->ether_dhost, etherbroadcastaddr,

                    sizeof(eh->ether_dhost));

                ea->arp_hrd = htons(ARPHRD_ETHER);

                break;

        }

        ea->arp_pro = htons(ETHERTYPE_IP);

        ea->arp_hln = sizeof(ea->arp_sha);      /* hardware address length */

        ea->arp_pln = sizeof(ea->arp_spa);      /* protocol address length */

        ea->arp_op = htons(ARPOP_REQUEST);

        (void)memcpy(ea->arp_sha, enaddr, sizeof(ea->arp_sha));

        (void)memcpy(ea->arp_spa, sip, sizeof(ea->arp_spa));

        (void)memcpy(ea->arp_tpa, tip, sizeof(ea->arp_tpa));

        sa.sa_family = AF_UNSPEC;

        sa.sa_len = sizeof(sa);

        (*ac->ac_if.if_output)(&ac->ac_if, m, &sa, (struct rtentry *)0);

}

/*

 * Resolve an IP address into an ethernet address.  If success,

 * desten is filled in.  If there is no entry in arptab,

 * set one up and broadcast a request for the IP address.

 * Hold onto this mbuf and resend it once the address

 * is finally resolved.  A return value of 1 indicates

 * that desten has been filled in and the packet should be sent

 * normally; a 0 return indicates that the packet has been

 * taken over here, either now or for later transmission.

 */

int

arpresolve(ac, rt, m, dst, desten, rt0)

        register struct arpcom *ac;

        register struct rtentry *rt;

        struct mbuf *m;

        register struct sockaddr *dst;

        register u_char *desten;

        struct rtentry *rt0;

{

        struct llinfo_arp *la = 0;

        struct sockaddr_dl *sdl;

        if (m->m_flags & M_BCAST) {     /* broadcast */

                (void)memcpy(desten, etherbroadcastaddr, sizeof(etherbroadcastaddr));

                return (1);

        }

        if (m->m_flags & M_MCAST) {     /* multicast */

                ETHER_MAP_IP_MULTICAST(&SIN(dst)->sin_addr, desten);

                return(1);

        }

        if (rt)

                la = (struct llinfo_arp *)rt->rt_llinfo;

        if (la == 0) {

                la = arplookup(SIN(dst)->sin_addr.s_addr, 1, 0);

                if (la)

                        rt = la->la_rt;

        }

        if (la == 0 || rt == 0) {

                log(LOG_DEBUG, "arpresolve: can't allocate llinfo for %s%s%s\n",

                        inet_ntoa(SIN(dst)->sin_addr), la ? "la" : "",

                                rt ? "rt" : "");

                m_freem(m);

                return (0);

        }

        sdl = SDL(rt->rt_gateway);

        /*

         * Check the address family and length is valid, the address

         * is resolved; otherwise, try to resolve.

         */

        if ((rt->rt_expire == 0 || rt->rt_expire > time_second) &&

            sdl->sdl_family == AF_LINK && sdl->sdl_alen != 0) {

                bcopy(LLADDR(sdl), desten, sdl->sdl_alen);

                return 1;

        }

        /*

         * If ARP is disabled on this interface, stop.

         * XXX

         * Probably should not allocate empty llinfo struct if we are

         * not going to be sending out an arp request.

         */

        if (ac->ac_if.if_flags & IFF_NOARP)

                return (0);

        /*

         * There is an arptab entry, but no ethernet address

         * response yet.  Replace the held mbuf with this

         * latest one.

         */

        if (la->la_hold)

                m_freem(la->la_hold);

        la->la_hold = m;

        if (rt->rt_expire) {

                rt->rt_flags &= ~RTF_REJECT;

                if (la->la_asked == 0 || rt->rt_expire != time_second) {

                        rt->rt_expire = time_second;

                        if (la->la_asked++ < arp_maxtries)

                            arprequest(ac,

                                &SIN(rt->rt_ifa->ifa_addr)->sin_addr,

                                &SIN(dst)->sin_addr, ac->ac_enaddr);

                        else {

                                rt->rt_flags |= RTF_REJECT;

                                rt->rt_expire += arpt_down;

                                la->la_asked = 0;

                        }

                }

        }

        return (0);

}

/*

 * Common length and type checks are done here,

 * then the protocol-specific routine is called.

 */

static void

arpintr()

{

        register struct mbuf *m;

        register struct arphdr *ar;

        int s;

        while (arpintrq.ifq_head) {

                s = splimp();

                IF_DEQUEUE(&arpintrq, m);

                splx(s);

                if (m == 0 || (m->m_flags & M_PKTHDR) == 0)

                        panic("arpintr");

                if (m->m_len < sizeof(struct arphdr) &&

                    ((m = m_pullup(m, sizeof(struct arphdr))) == NULL)) {

                        log(LOG_ERR, "arp: runt packet -- m_pullup failed\n");

                        continue;

                }

                ar = mtod(m, struct arphdr *);

                if (ntohs(ar->ar_hrd) != ARPHRD_ETHER

                    && ntohs(ar->ar_hrd) != ARPHRD_IEEE802) {

                        log(LOG_ERR,

                            "arp: unknown hardware address format (0x%2D)\n",

                            (unsigned char *)&ar->ar_hrd, "");

                        m_freem(m);

                        continue;

                }

                if (m->m_pkthdr.len < sizeof(struct arphdr) + 2 * ar->ar_hln

                    + 2 * ar->ar_pln) {

                        log(LOG_ERR, "arp: runt packet\n");

                        m_freem(m);

                        continue;

                }

                switch (ntohs(ar->ar_pro)) {

#ifdef INET

                        case ETHERTYPE_IP:

                                in_arpinput(m);

                                continue;

#endif

                }

                m_freem(m);

        }

}

#ifdef INET

/*

 * ARP for Internet protocols on 10 Mb/s Ethernet.

 * Algorithm is that given in RFC 826.

 * In addition, a sanity check is performed on the sender

 * protocol address, to catch impersonators.

 * We no longer handle negotiations for use of trailer protocol:

 * Formerly, ARP replied for protocol type ETHERTYPE_TRAIL sent

 * along with IP replies if we wanted trailers sent to us,

 * and also sent them in response to IP replies.

 * This allowed either end to announce the desire to receive

 * trailer packets.

 * We no longer reply to requests for ETHERTYPE_TRAIL protocol either,

 * but formerly didn't normally send requests.

 */

static int log_arp_wrong_iface = 1;

//SYSCTL_INT(_net_link_ether_inet, OID_AUTO, log_arp_wrong_iface, CTLFLAG_RW,

//      &log_arp_wrong_iface, 0,

//      "log arp packets arriving on the wrong interface");

static void

in_arpinput(m)

        struct mbuf *m;

{

        register struct ether_arp *ea;

        register struct arpcom *ac = (struct arpcom *)m->m_pkthdr.rcvif;

        struct ether_header *eh;

        struct iso88025_header *th = (struct iso88025_header *)0;

        register struct llinfo_arp *la = 0;

        register struct rtentry *rt;

        struct in_ifaddr *ia, *maybe_ia = 0;

        struct sockaddr_dl *sdl;

        struct sockaddr sa;

        struct in_addr isaddr, itaddr, myaddr;

        int op, rif_len;

        if (m->m_len < sizeof(struct ether_arp) &&

            (m = m_pullup(m, sizeof(struct ether_arp))) == NULL) {

                log(LOG_ERR, "in_arp: runt packet -- m_pullup failed\n");

                return;

        }

        ea = mtod(m, struct ether_arp *);

        op = ntohs(ea->arp_op);

        (void)memcpy(&isaddr, ea->arp_spa, sizeof (isaddr));

        (void)memcpy(&itaddr, ea->arp_tpa, sizeof (itaddr));

        for (ia = in_ifaddrhead.tqh_first; ia; ia = ia->ia_link.tqe_next) {

                /*

                 * For a bridge, we want to check the address irrespective

                 * of the receive interface. (This will change slightly

                 * when we have clusters of interfaces).

                 */

#ifdef BRIDGE

#define BRIDGE_TEST (do_bridge)

#else

#define BRIDGE_TEST (0) /* cc will optimise the test away */

#endif

                if ((BRIDGE_TEST) || (ia->ia_ifp == &ac->ac_if)) {

                        maybe_ia = ia;

                        if ((itaddr.s_addr == ia->ia_addr.sin_addr.s_addr) ||

                             (isaddr.s_addr == ia->ia_addr.sin_addr.s_addr)) {

                                break;

                        }

                }

        }

        if (maybe_ia == 0) {

                m_freem(m);

                return;

        }

        myaddr = ia ? ia->ia_addr.sin_addr : maybe_ia->ia_addr.sin_addr;

        if (!bcmp((caddr_t)ea->arp_sha, (caddr_t)ac->ac_enaddr,

            sizeof (ea->arp_sha))) {

                m_freem(m);     /* it's from me, ignore it. */

                return;

        }

        if (!bcmp((caddr_t)ea->arp_sha, (caddr_t)etherbroadcastaddr,

            sizeof (ea->arp_sha))) {

                log(LOG_ERR,

                    "arp: ether address is broadcast for IP address %s!\n",

                    inet_ntoa(isaddr));

                m_freem(m);

                return;

        }

        if (isaddr.s_addr == myaddr.s_addr) {

                log(LOG_ERR,

                   "arp: %6D is using my IP address %s!\n",

                   ea->arp_sha, ":", inet_ntoa(isaddr));

                itaddr = myaddr;

                goto reply;

        }

        la = arplookup(isaddr.s_addr, itaddr.s_addr == myaddr.s_addr, 0);

        if (la && (rt = la->la_rt) && (sdl = SDL(rt->rt_gateway))) {

                /* the following is not an error when doing bridging */

                if (!BRIDGE_TEST && rt->rt_ifp != &ac->ac_if) {

                    if (log_arp_wrong_iface)

                        log(LOG_ERR, "arp: %s is on %s%d but got reply from %6D on %s%d\n",

                            inet_ntoa(isaddr),

                            rt->rt_ifp->if_name, rt->rt_ifp->if_unit,

                            ea->arp_sha, ":",

                            ac->ac_if.if_name, ac->ac_if.if_unit);

                    goto reply;

                }

                if (sdl->sdl_alen &&

                    bcmp((caddr_t)ea->arp_sha, LLADDR(sdl), sdl->sdl_alen)) {

                        if (rt->rt_expire)

                            log(LOG_INFO, "arp: %s moved from %6D to %6D on %s%d\n",

                                inet_ntoa(isaddr), (u_char *)LLADDR(sdl), ":",

                                ea->arp_sha, ":",

                                ac->ac_if.if_name, ac->ac_if.if_unit);

                        else {

                            log(LOG_ERR,

                                "arp: %6D attempts to modify permanent entry for %s on %s%d\n",

                                ea->arp_sha, ":", inet_ntoa(isaddr),

                                ac->ac_if.if_name, ac->ac_if.if_unit);

                            goto reply;

                        }

                }

                (void)memcpy(LLADDR(sdl), ea->arp_sha, sizeof(ea->arp_sha));

                sdl->sdl_alen = sizeof(ea->arp_sha);

                sdl->sdl_rcf = (u_short)0;

                /*

                 * If we receive an arp from a token-ring station over

                 * a token-ring nic then try to save the source

                 * routing info.

                 */

                if (ac->ac_if.if_type == IFT_ISO88025) {

                        th = (struct iso88025_header *)m->m_pkthdr.header;

                        rif_len = TR_RCF_RIFLEN(th->rcf);

                        if ((th->iso88025_shost[0] & TR_RII) &&

                            (rif_len > 2)) {

                                sdl->sdl_rcf = th->rcf;

                                sdl->sdl_rcf ^= htons(TR_RCF_DIR);

                                memcpy(sdl->sdl_route, th->rd, rif_len - 2);

                                sdl->sdl_rcf &= ~htons(TR_RCF_BCST_MASK);

                                /*

                                 * Set up source routing information for

                                 * reply packet (XXX)

                                 */

                                m->m_data -= rif_len;

                                m->m_len  += rif_len;

                                m->m_pkthdr.len += rif_len;

                        } else {

                                th->iso88025_shost[0] &= ~TR_RII;

                        }

                        m->m_data -= 8;