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/*
 * Copyright (c) 1982, 1989, 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.
 * 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_ethersubr.c	8.1 (Berkeley) 6/10/93
 * $FreeBSD: src/sys/net/if_ethersubr.c,v 1.189 2005/03/06 22:59:40 sobomax Exp $
 */
 

#ifdef HAVE_CONFIG_H
#include "config.h"
#endif

#include "opt_atalk.h"
#include "opt_inet.h"
#include "opt_inet6.h"
#include "opt_ipx.h"
#include "opt_bdg.h"
#include "opt_mac.h"
#include "opt_netgraph.h"

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/malloc.h>
#include <sys/mbuf.h>
#include <sys/protosw.h>
#include <sys/socket.h>
#include <sys/sockio.h>
#include <errno.h>
#include <sys/syslog.h>
#include <sys/sysctl.h>

#include <net/if.h>
#include <net/if_arp.h>
#include <net/netisr.h>
#include <net/route.h>
#include <net/if_llc.h>
#include <net/if_dl.h>
#include <net/if_types.h>
#include <net/ethernet.h>

#if defined(INET) || defined(INET6)
#include <netinet/in.h>
#include <netinet/in_var.h>
#include <netinet/if_ether.h>
#include <netinet/ip_fw.h>
#ifndef __rtems__
#include <netinet/ip_dummynet.h>
#endif
#endif
#ifdef INET6
#include <netinet6/nd6.h>
#endif

#ifdef DEV_CARP
#include <netinet/ip_carp.h>
#endif

#ifdef IPX
#include <netipx/ipx.h>
#include <netipx/ipx_if.h>
#endif

#ifdef NETATALK
#include <netatalk/at.h>
#include <netatalk/at_var.h>
#include <netatalk/at_extern.h>

#define llc_snap_org_code llc_un.type_snap.org_code
#define llc_snap_ether_type llc_un.type_snap.ether_type

extern u_char	at_org_code[3];
extern u_char	aarp_org_code[3];
#endif /* NETATALK */

u_char	etherbroadcastaddr[6] = { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff };
#define senderr(e) do { error = (e); goto bad;} while (0)

/*
 * Ethernet output routine.
 * Encapsulate a packet of type family for the local net.
 * Use trailer local net encapsulation if enough data in first
 * packet leaves a multiple of 512 bytes of data in remainder.
 * Assumes that ifp is actually pointer to arpcom structure.
 */
int
ether_output(struct ifnet *ifp, struct mbuf *m,
	struct sockaddr *dst, struct rtentry *rt0)
{
	short type;
	int s, error = 0;
	u_char  edst[6];
	register struct rtentry *rt;
	struct mbuf *mcopy = (struct mbuf *)0;
	register struct ether_header *eh;
	int len = m->m_pkthdr.len;
	struct arpcom *ac = (struct arpcom *)ifp;
#ifdef NETATALK
	struct at_ifaddr *aa;
#endif /* NETATALK */

	if ((ifp->if_flags & (IFF_UP|IFF_RUNNING)) != (IFF_UP|IFF_RUNNING))
		senderr(ENETDOWN);
	rt = rt0;
	if (rt) {
		if ((rt->rt_flags & RTF_UP) == 0) {
			rt0 = rt = rtalloc1(dst, 1, 0UL);
			if (rt0)
				rt->rt_refcnt--;
			else
				senderr(EHOSTUNREACH);
		}
		if (rt->rt_flags & RTF_GATEWAY) {
			if (rt->rt_gwroute == 0)
				goto lookup;
			if (((rt = rt->rt_gwroute)->rt_flags & RTF_UP) == 0) {
				rtfree(rt); rt = rt0;
			lookup: rt->rt_gwroute = rtalloc1(rt->rt_gateway, 1,
							  0UL);
				if ((rt = rt->rt_gwroute) == 0)
					senderr(EHOSTUNREACH);
			}
		}
		if (rt->rt_flags & RTF_REJECT)
			if (rt->rt_rmx.rmx_expire == 0 ||
			    rtems_bsdnet_seconds_since_boot() < rt->rt_rmx.rmx_expire)
				senderr(rt == rt0 ? EHOSTDOWN : EHOSTUNREACH);
	}
	switch (dst->sa_family) {

#ifdef INET
	case AF_INET:
		if (!arpresolve(ac, rt, m, dst, edst, rt0))
			return (0);	/* if not yet resolved */
		/* If broadcasting on a simplex interface, loopback a copy */
		if ((m->m_flags & M_BCAST) && (ifp->if_flags & IFF_SIMPLEX))
			mcopy = m_copy(m, 0, (int)M_COPYALL);
		type = htons(ETHERTYPE_IP);
		break;
#endif
#ifdef IPX
	case AF_IPX:
		{
		struct ifaddr *ia;

		type = htons(ETHERTYPE_IPX);
 		bcopy((caddr_t)&(((struct sockaddr_ipx *)dst)->sipx_addr.x_host),
		    (caddr_t)edst, sizeof (edst));
		for (ia = ifp->if_addrlist; ia != NULL; ia = ia->ifa_next)
			if(ia->ifa_addr->sa_family == AF_IPX &&
			   !bcmp((caddr_t)edst,
				 (caddr_t)&((struct ipx_ifaddr *)ia)->ia_addr.sipx_addr.x_host,
				 sizeof(edst)))
				return (looutput(ifp, m, dst, rt));
		/* If broadcasting on a simplex interface, loopback a copy */
		if ((m->m_flags & M_BCAST) && (ifp->if_flags & IFF_SIMPLEX))
			mcopy = m_copy(m, 0, (int)M_COPYALL);
		break;
		}
#endif
#ifdef NETATALK
	case AF_APPLETALK:
	    {
		struct sockaddr_at *sat = (struct sockaddr_at *)dst;

		/*
		 * super hack..
		 * Most of this loopback code should move into the appletalk
		 * code, but it's here for now.. remember to move it! [JRE]
		 * This may not get the same interface we started with
		 * fix asap. XXX
		 */
		aa = at_ifawithnet( sat );
		if (aa == NULL) {
			goto bad;
		}
		if( aa->aa_ifa.ifa_ifp != ifp ) {
			(*aa->aa_ifa.ifa_ifp->if_output)(aa->aa_ifa.ifa_ifp,
							m,dst,rt);
		}
		if (((sat->sat_addr.s_net == ATADDR_ANYNET)
		  && (sat->sat_addr.s_node == ATADDR_ANYNODE))
		|| ((sat->sat_addr.s_net == aa->aa_addr.sat_addr.s_net )
		  && (sat->sat_addr.s_node == aa->aa_addr.sat_addr.s_node))) {
			(void) looutput(ifp, m, dst, rt);
			return(0);
		}

        	if (!aarpresolve(ac, m, (struct sockaddr_at *)dst, edst)) {
#ifdef NETATALKDEBUG
                	extern char *prsockaddr(struct sockaddr *);
                	printf("aarpresolv: failed for %s\n", prsockaddr(dst));
#endif /* NETATALKDEBUG */
                	return (0);
        	}

		/*
		 * If broadcasting on a simplex interface, loopback a copy
		 */
		if ((m->m_flags & M_BCAST) && (ifp->if_flags & IFF_SIMPLEX))
			mcopy = m_copy(m, 0, (int)M_COPYALL);
	    }
	    /*
	     * In the phase 2 case, we need to prepend an mbuf for the llc header.
	     * Since we must preserve the value of m, which is passed to us by
	     * value, we m_copy() the first mbuf, and use it for our llc header.
	     */
	    if ( aa->aa_flags & AFA_PHASE2 ) {
		struct llc llc;

		M_PREPEND(m, sizeof(struct llc), M_WAIT);
		len += sizeof(struct llc);
		llc.llc_dsap = llc.llc_ssap = LLC_SNAP_LSAP;
		llc.llc_control = LLC_UI;
		bcopy(at_org_code, llc.llc_snap_org_code, sizeof(at_org_code));
		llc.llc_snap_ether_type = htons( ETHERTYPE_AT );
		bcopy(&llc, mtod(m, caddr_t), sizeof(struct llc));
		type = htons(m->m_pkthdr.len);
	    } else {
		type = htons(ETHERTYPE_AT);
	    }
	    break;
#endif /* NETATALK */

	case AF_UNSPEC:
		eh = (struct ether_header *)dst->sa_data;
		(void)memcpy(edst, eh->ether_dhost, sizeof (edst));
		type = eh->ether_type;
		break;

	default:
		printf("%s%d: can't handle af%d\n", ifp->if_name, ifp->if_unit,
			dst->sa_family);
		senderr(EAFNOSUPPORT);
	}


	if (mcopy)
		(void) looutput(ifp, mcopy, dst, rt);
	/*
	 * Add local net header.  If no space in first mbuf,
	 * allocate another.
	 */
	M_PREPEND(m, sizeof (struct ether_header), M_DONTWAIT);
	if (m == NULL)
		senderr(ENOBUFS);
	eh = mtod(m, struct ether_header *);
	(void)memcpy(&eh->ether_type, &type,
		sizeof(eh->ether_type));
 	(void)memcpy(eh->ether_dhost, edst, sizeof (edst));
 	(void)memcpy(eh->ether_shost, ac->ac_enaddr,
	    sizeof(eh->ether_shost));
	s = splimp();
	/*
	 * Queue message on interface, and start output if interface
	 * not yet active.
	 */
	if (IF_QFULL(&ifp->if_snd)) {
		IF_DROP(&ifp->if_snd);
		splx(s);
		senderr(ENOBUFS);
	}
	IF_ENQUEUE(&ifp->if_snd, m);
	if ((ifp->if_flags & IFF_OACTIVE) == 0)
		(*ifp->if_start)(ifp);
	splx(s);
	ifp->if_obytes += len + sizeof (struct ether_header);
	if (m->m_flags & M_MCAST)
		ifp->if_omcasts++;
	return (error);

bad:
	if (m)
		m_freem(m);
	return (error);
}

/*
 * Process a received Ethernet packet;
 * the packet is in the mbuf chain m without
 * the ether header, which is provided separately.
 */
void
ether_input(struct ifnet *ifp, struct ether_header *eh, struct mbuf *m)
{
	register struct ifqueue *inq;
	u_short ether_type;
	int s;
#if defined(NETATALK)
	struct llc *l;
#endif

	if ((ifp->if_flags & IFF_UP) == 0) {
		m_freem(m);
		return;
	}
	ifp->if_ibytes += m->m_pkthdr.len + sizeof (*eh);
	if (bcmp((caddr_t)etherbroadcastaddr, (caddr_t)eh->ether_dhost,
	    sizeof(etherbroadcastaddr)) == 0)
		m->m_flags |= M_BCAST;
	else if (eh->ether_dhost[0] & 1)
		m->m_flags |= M_MCAST;
	if (m->m_flags & (M_BCAST|M_MCAST))
		ifp->if_imcasts++;

	/*
	 * RTEMS addition -- allow application to `tap into'
	 * the incoming packet stream.
	 */
	if (ifp->if_tap && (*ifp->if_tap)(ifp, eh, m)) {
		m_freem(m);
		return;
	}

	ether_type = ntohs(eh->ether_type);

	switch (ether_type) {
#ifdef INET
	case ETHERTYPE_IP:
		schednetisr(NETISR_IP);
		inq = &ipintrq;
		break;

	case ETHERTYPE_ARP:
		schednetisr(NETISR_ARP);
		inq = &arpintrq;
		break;
#endif
#ifdef IPX
	case ETHERTYPE_IPX:
		schednetisr(NETISR_IPX);
		inq = &ipxintrq;
		break;
#endif
#ifdef NETATALK
        case ETHERTYPE_AT:
                schednetisr(NETISR_ATALK);
                inq = &atintrq1;
                break;
        case ETHERTYPE_AARP:
		/* probably this should be done with a NETISR as well */
                aarpinput((struct arpcom *)ifp, m); /* XXX */
                return;
#endif /* NETATALK */
	default:
#if defined (ISO) || defined (LLC) || defined(NETATALK)
		if (ether_type > ETHERMTU)
			goto dropanyway;
		l = mtod(m, struct llc *);
		switch (l->llc_dsap) {
#ifdef NETATALK
		case LLC_SNAP_LSAP:
		    switch (l->llc_control) {
		    case LLC_UI:
			if (l->llc_ssap != LLC_SNAP_LSAP)
			    goto dropanyway;
	
			if (Bcmp(&(l->llc_snap_org_code)[0], at_org_code,
				   sizeof(at_org_code)) == 0 &&
			     ntohs(l->llc_snap_ether_type) == ETHERTYPE_AT) {
			    inq = &atintrq2;
			    m_adj( m, sizeof( struct llc ));
			    schednetisr(NETISR_ATALK);
			    break;
			}

			if (Bcmp(&(l->llc_snap_org_code)[0], aarp_org_code,
				   sizeof(aarp_org_code)) == 0 &&
			     ntohs(l->llc_snap_ether_type) == ETHERTYPE_AARP) {
			    m_adj( m, sizeof( struct llc ));
			    aarpinput((struct arpcom *)ifp, m); /* XXX */
			    return;
			}
		
		    default:
			goto dropanyway;
		    }
		    break;
#endif /* NETATALK */
#ifdef	ISO
		case LLC_ISO_LSAP:
			switch (l->llc_control) {
			case LLC_UI:
				/* LLC_UI_P forbidden in class 1 service */
				if ((l->llc_dsap == LLC_ISO_LSAP) &&
				    (l->llc_ssap == LLC_ISO_LSAP)) {
					/* LSAP for ISO */
					if (m->m_pkthdr.len > ether_type)
						m_adj(m, ether_type - m->m_pkthdr.len);
					m->m_data += 3;		/* XXX */
					m->m_len -= 3;		/* XXX */
					m->m_pkthdr.len -= 3;	/* XXX */
					M_PREPEND(m, sizeof *eh, M_DONTWAIT);
					if (m == 0)
						return;
					*mtod(m, struct ether_header *) = *eh;
					IFDEBUG(D_ETHER)
						printf("clnp packet");
					ENDDEBUG
					schednetisr(NETISR_ISO);
					inq = &clnlintrq;
					break;
				}
				goto dropanyway;

			case LLC_XID:
			case LLC_XID_P:
				if(m->m_len < 6)
					goto dropanyway;
				l->llc_window = 0;
				l->llc_fid = 9;
				l->llc_class = 1;
				l->llc_dsap = l->llc_ssap = 0;
				/* Fall through to */
			case LLC_TEST:
			case LLC_TEST_P:
			{
				struct sockaddr sa;
				register struct ether_header *eh2;
				int i;
				u_char c = l->llc_dsap;

				l->llc_dsap = l->llc_ssap;
				l->llc_ssap = c;
				if (m->m_flags & (M_BCAST | M_MCAST))
					bcopy((caddr_t)ac->ac_enaddr,
					      (caddr_t)eh->ether_dhost, 6);
				sa.sa_family = AF_UNSPEC;
				sa.sa_len = sizeof(sa);
				eh2 = (struct ether_header *)sa.sa_data;
				for (i = 0; i < 6; i++) {
					eh2->ether_shost[i] = c = eh->ether_dhost[i];
					eh2->ether_dhost[i] =
						eh->ether_dhost[i] = eh->ether_shost[i];
					eh->ether_shost[i] = c;
				}
				ifp->if_output(ifp, m, &sa, NULL);
				return;
			}
			default:
				m_freem(m);
				return;
			}
			break;
#endif /* ISO */
#ifdef LLC
		case LLC_X25_LSAP:
		{
			if (m->m_pkthdr.len > ether_type)
				m_adj(m, ether_type - m->m_pkthdr.len);
			M_PREPEND(m, sizeof(struct sdl_hdr) , M_DONTWAIT);
			if (m == 0)
				return;
			if ( !sdl_sethdrif(ifp, eh->ether_shost, LLC_X25_LSAP,
					    eh->ether_dhost, LLC_X25_LSAP, 6,
					    mtod(m, struct sdl_hdr *)))
				panic("ETHER cons addr failure");
			mtod(m, struct sdl_hdr *)->sdlhdr_len = ether_type;
#ifdef LLC_DEBUG
				printf("llc packet\n");
#endif /* LLC_DEBUG */
			schednetisr(NETISR_CCITT);
			inq = &llcintrq;
			break;
		}
#endif /* LLC */
		dropanyway:
		default:
			m_freem(m);
			return;
		}
#else /* ISO || LLC || NETATALK */
	    m_freem(m);
	    return;
#endif /* ISO || LLC || NETATALK */
	}

	s = splimp();
	if (IF_QFULL(inq)) {
		IF_DROP(inq);
		m_freem(m);
	} else
		IF_ENQUEUE(inq, m);
	splx(s);
}

/*
 * Convert Ethernet address to printable (loggable) representation.
 * The static buffer isn't a really huge problem since this code
 * is protected by the RTEMS network mutex.
 */
char *
ether_sprintf(const u_char *ap)
{
	static char buf[32];
	char *b = buf;
	int i;

	for (i = 0; i < ETHER_ADDR_LEN; i++, b+=3)
		sprintf(b, "%02x:", *ap++);
	*--b = '\0';
	return buf;
}

/*
 * Perform common duties while attaching to interface list
 */
void
ether_ifattach(struct ifnet *ifp)
{
	struct ifaddr *ifa;
	struct sockaddr_dl *sdl;

	ifp->if_type = IFT_ETHER;
	ifp->if_addrlen = ETHER_ADDR_LEN;
	ifp->if_hdrlen = ETHER_HDR_LEN;
	ifp->if_mtu = ETHERMTU;
	if (ifp->if_baudrate == 0)
	    ifp->if_baudrate = 10000000;
	for (ifa = ifp->if_addrlist; ifa; ifa = ifa->ifa_next)
		if ((sdl = (struct sockaddr_dl *)ifa->ifa_addr) &&
		    sdl->sdl_family == AF_LINK) {
			sdl->sdl_type = IFT_ETHER;
			sdl->sdl_alen = ifp->if_addrlen;
			bcopy((caddr_t)((struct arpcom *)ifp)->ac_enaddr,
			      LLADDR(sdl), ifp->if_addrlen);
			break;
		}
}

#if defined(__rtems__)
u_char ether_ipmulticast_min[6] = 
	{ 0x01, 0x00, 0x5e, 0x00, 0x00, 0x00 };
u_char ether_ipmulticast_max[6] =
	{ 0x01, 0x00, 0x5e, 0x7f, 0xff, 0xff };
#else
static u_char ether_ipmulticast_min[6] = 
	{ 0x01, 0x00, 0x5e, 0x00, 0x00, 0x00 };
static u_char ether_ipmulticast_max[6] =
	{ 0x01, 0x00, 0x5e, 0x7f, 0xff, 0xff };
#endif

/*
 * Add an Ethernet multicast address or range of addresses to the list for a
 * given interface.
 */
int
ether_addmulti(struct ifreq *ifr, struct arpcom *ac)
{
	register struct ether_multi *enm;
	struct sockaddr_in *sin;
	u_char addrlo[6];
	u_char addrhi[6];
        int set_allmulti = 0;
	int s = splimp();

	switch (ifr->ifr_addr.sa_family) {

	case AF_UNSPEC:
		bcopy(ifr->ifr_addr.sa_data, addrlo, 6);
		bcopy(addrlo, addrhi, 6);
		break;

#ifdef INET
	case AF_INET:
		sin = (struct sockaddr_in *)&(ifr->ifr_addr);
		if (sin->sin_addr.s_addr == INADDR_ANY) {
			/*
			 * An IP address of INADDR_ANY means listen to all
			 * of the Ethernet multicast addresses used for IP.
			 * (This is for the sake of IP multicast routers.)
			 */
			bcopy(ether_ipmulticast_min, addrlo, 6);
			bcopy(ether_ipmulticast_max, addrhi, 6);
                      set_allmulti = 1;
		}
		else {
			ETHER_MAP_IP_MULTICAST(&sin->sin_addr, addrlo);
			bcopy(addrlo, addrhi, 6);
		}
		break;
#endif

	default:
		splx(s);
		return (EAFNOSUPPORT);
	}

	/*
	 * Verify that we have valid Ethernet multicast addresses.
	 */
	if ((addrlo[0] & 0x01) != 1 || (addrhi[0] & 0x01) != 1) {
		splx(s);
		return (EINVAL);
	}
	/*
	 * See if the address range is already in the list.
	 */
	ETHER_LOOKUP_MULTI(addrlo, addrhi, ac, enm);
	if (enm != NULL) {
		/*
		 * Found it; just increment the reference count.
		 */
		++enm->enm_refcount;
		splx(s);
		return (0);
	}
	/*
	 * New address or range; malloc a new multicast record
	 * and link it into the interface's multicast list.
	 */
	enm = (struct ether_multi *)malloc(sizeof(*enm), M_IFMADDR, M_NOWAIT);
	if (enm == NULL) {
		splx(s);
		return (ENOBUFS);
	}
	bcopy(addrlo, enm->enm_addrlo, 6);
	bcopy(addrhi, enm->enm_addrhi, 6);
	enm->enm_ac = ac;
	enm->enm_refcount = 1;
	enm->enm_next = ac->ac_multiaddrs;
	ac->ac_multiaddrs = enm;
	ac->ac_multicnt++;
	splx(s);
        if (set_allmulti)
        	ac->ac_if.if_flags |= IFF_ALLMULTI;

	/*
	 * Return ENETRESET to inform the driver that the list has changed
	 * and its reception filter should be adjusted accordingly.
	 */
	return (ENETRESET);
}

/*
 * Delete a multicast address record.
 */
int
ether_delmulti(struct ifreq *ifr, struct arpcom *ac)
{
	register struct ether_multi *enm;
	register struct ether_multi **p;
	struct sockaddr_in *sin;
	u_char addrlo[6];
	u_char addrhi[6];
      int unset_allmulti = 0;
	int s = splimp();

	switch (ifr->ifr_addr.sa_family) {

	case AF_UNSPEC:
		bcopy(ifr->ifr_addr.sa_data, addrlo, 6);
		bcopy(addrlo, addrhi, 6);
		break;

#ifdef INET
	case AF_INET:
		sin = (struct sockaddr_in *)&(ifr->ifr_addr);
		if (sin->sin_addr.s_addr == INADDR_ANY) {
			/*
			 * An IP address of INADDR_ANY means stop listening
			 * to the range of Ethernet multicast addresses used
			 * for IP.
			 */
			bcopy(ether_ipmulticast_min, addrlo, 6);
			bcopy(ether_ipmulticast_max, addrhi, 6);
                      unset_allmulti = 1;
		}
		else {
			ETHER_MAP_IP_MULTICAST(&sin->sin_addr, addrlo);
			bcopy(addrlo, addrhi, 6);
		}
		break;
#endif

	default:
		splx(s);
		return (EAFNOSUPPORT);
	}

	/*
	 * Look up the address in our list.
	 */
	ETHER_LOOKUP_MULTI(addrlo, addrhi, ac, enm);
	if (enm == NULL) {
		splx(s);
		return (ENXIO);
	}
	if (--enm->enm_refcount != 0) {
		/*
		 * Still some claims to this record.
		 */
		splx(s);
		return (0);
	}
	/*
	 * No remaining claims to this record; unlink and free it.
	 */
	for (p = &enm->enm_ac->ac_multiaddrs;
	     *p != enm;
	     p = &(*p)->enm_next)
		continue;
	*p = (*p)->enm_next;
	free(enm, M_IFMADDR);
	ac->ac_multicnt--;
	splx(s);
      if (unset_allmulti)
              ac->ac_if.if_flags &= ~IFF_ALLMULTI;

	/*
	 * Return ENETRESET to inform the driver that the list has changed
	 * and its reception filter should be adjusted accordingly.
	 */
	return (ENETRESET);
}

SYSCTL_DECL(_net_link);
SYSCTL_NODE(_net_link, IFT_ETHER, ether, CTLFLAG_RW, 0, "Ethernet");

#if 0
/*
 * This is for reference.  We have a table-driven version
 * of the little-endian crc32 generator, which is faster
 * than the double-loop.
 */
uint32_t
ether_crc32_le(const uint8_t *buf, size_t len)
{
	size_t i;
	uint32_t crc;
	int bit;
	uint8_t data;

	crc = 0xffffffff;	/* initial value */

	for (i = 0; i < len; i++) {
		for (data = *buf++, bit = 0; bit < 8; bit++, data >>= 1)
			carry = (crc ^ data) & 1;
			crc >>= 1;
			if (carry)
				crc = (crc ^ ETHER_CRC_POLY_LE);
	}

	return (crc);
}
#else
uint32_t
ether_crc32_le(const uint8_t *buf, size_t len)
{
	static const uint32_t crctab[] = {
		0x00000000, 0x1db71064, 0x3b6e20c8, 0x26d930ac,
		0x76dc4190, 0x6b6b51f4, 0x4db26158, 0x5005713c,
		0xedb88320, 0xf00f9344, 0xd6d6a3e8, 0xcb61b38c,
		0x9b64c2b0, 0x86d3d2d4, 0xa00ae278, 0xbdbdf21c
	};
	size_t i;
	uint32_t crc;

	crc = 0xffffffff;	/* initial value */

	for (i = 0; i < len; i++) {
		crc ^= buf[i];
		crc = (crc >> 4) ^ crctab[crc & 0xf];
		crc = (crc >> 4) ^ crctab[crc & 0xf];
	}

	return (crc);
}
#endif

uint32_t
ether_crc32_be(const uint8_t *buf, size_t len)
{
	size_t i;
	uint32_t crc, carry;
	int bit;
	uint8_t data;

	crc = 0xffffffff;	/* initial value */

	for (i = 0; i < len; i++) {
		for (data = *buf++, bit = 0; bit < 8; bit++, data >>= 1) {
			carry = ((crc & 0x80000000) ? 1 : 0) ^ (data & 0x01);
			crc <<= 1;
			if (carry)
				crc = (crc ^ ETHER_CRC_POLY_BE) | carry;
		}
	}

	return (crc);
}

int
ether_ioctl(struct ifnet *ifp, ioctl_command_t command, caddr_t data)
{
	struct ifaddr *ifa = (struct ifaddr *) data;
	struct ifreq *ifr = (struct ifreq *) data;
	int error = 0;

	switch (command) {
	case SIOCSIFADDR:
		ifp->if_flags |= IFF_UP;

		switch (ifa->ifa_addr->sa_family) {
#ifdef INET
		case AF_INET:
			ifp->if_init(ifp->if_softc);	/* before arpwhohas */
			arp_ifinit((struct arpcom *)ifp, ifa);
			break;
#endif
#ifdef IPX
		/*
		 * XXX - This code is probably wrong
		 */
		case AF_IPX:
			{
			struct ipx_addr *ina = &(IA_SIPX(ifa)->sipx_addr);
			struct arpcom *ac = (struct arpcom *) (ifp->if_softc);

			if (ipx_nullhost(*ina))
				ina->x_host =
				    *(union ipx_host *) 
			            ac->ac_enaddr;
			else {
				bcopy((caddr_t) ina->x_host.c_host,
				      (caddr_t) ac->ac_enaddr,
				      sizeof(ac->ac_enaddr));
			}

			/*
			 * Set new address
			 */
			ifp->if_init(ifp->if_softc);
			break;
			}
#endif
		default:
			ifp->if_init(ifp->if_softc);
			break;
		}
		break;

	case SIOCGIFADDR:
		{
			struct sockaddr *sa;

			sa = (struct sockaddr *) & ifr->ifr_data;
			bcopy(((struct arpcom *)ifp->if_softc)->ac_enaddr,
			      (caddr_t) sa->sa_data, ETHER_ADDR_LEN);
		}
		break;

	case SIOCSIFMTU:
		/*
		 * Set the interface MTU.
		 */
		if (ifr->ifr_mtu > ETHERMTU) {
			error = EINVAL;
		} else {
			ifp->if_mtu = ifr->ifr_mtu;
		}
		break;
	default:
		error = EINVAL;			/* XXX netbsd has ENOTTY??? */
		break;
	}
	return (error);
}