if_arcsubr.c revision 105228
1/*	$NetBSD: if_arcsubr.c,v 1.36 2001/06/14 05:44:23 itojun Exp $	*/
2/*	$FreeBSD: head/sys/net/if_arcsubr.c 105228 2002-10-16 10:45:53Z phk $ */
3
4/*
5 * Copyright (c) 1994, 1995 Ignatios Souvatzis
6 * Copyright (c) 1982, 1989, 1993
7 *	The Regents of the University of California.  All rights reserved.
8 *
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
11 * are met:
12 * 1. Redistributions of source code must retain the above copyright
13 *    notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 *    notice, this list of conditions and the following disclaimer in the
16 *    documentation and/or other materials provided with the distribution.
17 * 3. All advertising materials mentioning features or use of this software
18 *    must display the following acknowledgement:
19 *	This product includes software developed by the University of
20 *	California, Berkeley and its contributors.
21 * 4. Neither the name of the University nor the names of its contributors
22 *    may be used to endorse or promote products derived from this software
23 *    without specific prior written permission.
24 *
25 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
26 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
27 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
28 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
29 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
30 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
31 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
32 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
33 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
34 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
35 * SUCH DAMAGE.
36 *
37 * from: NetBSD: if_ethersubr.c,v 1.9 1994/06/29 06:36:11 cgd Exp
38 *       @(#)if_ethersubr.c	8.1 (Berkeley) 6/10/93
39 *
40 */
41#include "opt_inet.h"
42#include "opt_inet6.h"
43
44#include <sys/param.h>
45#include <sys/systm.h>
46#include <sys/kernel.h>
47#include <sys/malloc.h>
48#include <sys/mbuf.h>
49#include <sys/protosw.h>
50#include <sys/socket.h>
51#include <sys/sockio.h>
52#include <sys/errno.h>
53#include <sys/syslog.h>
54
55#include <machine/cpu.h>
56
57#include <net/if.h>
58#include <net/netisr.h>
59#include <net/route.h>
60#include <net/if_dl.h>
61#include <net/if_types.h>
62#include <net/if_arc.h>
63#include <net/if_arp.h>
64#include <net/bpf.h>
65
66#if defined(INET) || defined(INET6)
67#include <netinet/in.h>
68#include <netinet/in_var.h>
69#include <netinet/if_ether.h>
70#endif
71
72#ifdef INET6
73#include <netinet6/nd6.h>
74#endif
75
76MODULE_VERSION(arcnet, 1);
77
78#define ARCNET_ALLOW_BROKEN_ARP
79
80static struct mbuf *arc_defrag(struct ifnet *, struct mbuf *);
81
82u_int8_t  arcbroadcastaddr = 0;
83
84#define senderr(e) { error = (e); goto bad;}
85#define SIN(s) ((struct sockaddr_in *)s)
86
87/*
88 * ARCnet output routine.
89 * Encapsulate a packet of type family for the local net.
90 * Assumes that ifp is actually pointer to arccom structure.
91 */
92int
93arc_output(ifp, m, dst, rt0)
94	struct ifnet *ifp;
95	struct mbuf *m;
96	struct sockaddr *dst;
97	struct rtentry *rt0;
98{
99	struct mbuf		*mcopy;
100	struct rtentry		*rt;
101	struct arccom		*ac;
102	struct arc_header	*ah;
103	struct arphdr		*arph;
104	int			error;
105	u_int8_t		atype, adst;
106#if __FreeBSD_version < 500000
107	int			s;
108#endif
109
110	if ((ifp->if_flags & (IFF_UP|IFF_RUNNING)) != (IFF_UP|IFF_RUNNING))
111		return(ENETDOWN); /* m, m1 aren't initialized yet */
112
113	error = 0;
114	ac = (struct arccom *)ifp;
115	mcopy = NULL;
116
117	if ((rt = rt0)) {
118		if ((rt->rt_flags & RTF_UP) == 0) {
119			if ((rt0 = rt = rtalloc1(dst, 1, 0UL)))
120				rt->rt_refcnt--;
121			else
122				senderr(EHOSTUNREACH);
123		}
124		if (rt->rt_flags & RTF_GATEWAY) {
125			if (rt->rt_gwroute == 0)
126				goto lookup;
127			if (((rt = rt->rt_gwroute)->rt_flags & RTF_UP) == 0) {
128				rtfree(rt); rt = rt0;
129			lookup: rt->rt_gwroute = rtalloc1(rt->rt_gateway, 1, 0UL);
130				if ((rt = rt->rt_gwroute) == 0)
131					senderr(EHOSTUNREACH);
132			}
133		}
134		if (rt->rt_flags & RTF_REJECT)
135			if (rt->rt_rmx.rmx_expire == 0 ||
136			    time_second < rt->rt_rmx.rmx_expire)
137				senderr(rt == rt0 ? EHOSTDOWN : EHOSTUNREACH);
138	}
139
140	switch (dst->sa_family) {
141#ifdef INET
142	case AF_INET:
143
144		/*
145		 * For now, use the simple IP addr -> ARCnet addr mapping
146		 */
147		if (m->m_flags & (M_BCAST|M_MCAST))
148			adst = arcbroadcastaddr; /* ARCnet broadcast address */
149		else if (ifp->if_flags & IFF_NOARP)
150			adst = ntohl(SIN(dst)->sin_addr.s_addr) & 0xFF;
151		else if (!arpresolve(ifp, rt, m, dst, &adst, rt0))
152			return 0;	/* not resolved yet */
153
154		/* If broadcasting on a simplex interface, loopback a copy */
155		if ((m->m_flags & (M_BCAST|M_MCAST)) &&
156		    (ifp->if_flags & IFF_SIMPLEX))
157			mcopy = m_copy(m, 0, (int)M_COPYALL);
158		atype = (ifp->if_flags & IFF_LINK0) ?
159			ARCTYPE_IP_OLD : ARCTYPE_IP;
160		break;
161#endif
162#ifdef INET6
163	case AF_INET6:
164#ifdef OLDIP6OUTPUT
165		if (!nd6_resolve(ifp, rt, m, dst, (u_char *)&adst))
166			return(0);	/* if not yet resolves */
167#else
168		if (!nd6_storelladdr(ifp, rt, m, dst, (u_char *)&adst))
169			return(0); /* it must be impossible, but... */
170#endif /* OLDIP6OUTPUT */
171		atype = ARCTYPE_INET6;
172		break;
173#endif
174
175	case AF_UNSPEC:
176		ah = (struct arc_header *)dst->sa_data;
177		adst = ah->arc_dhost;
178		atype = ah->arc_type;
179
180		if (atype == ARCTYPE_ARP) {
181			atype = (ifp->if_flags & IFF_LINK0) ?
182			    ARCTYPE_ARP_OLD: ARCTYPE_ARP;
183
184#ifdef ARCNET_ALLOW_BROKEN_ARP
185			/*
186			 * XXX It's not clear per RFC826 if this is needed, but
187			 * "assigned numbers" say this is wrong.
188			 * However, e.g., AmiTCP 3.0Beta used it... we make this
189			 * switchable for emergency cases. Not perfect, but...
190			 */
191			arph = mtod(m, struct arphdr *);
192			if (ifp->if_flags & IFF_LINK2)
193				arph->ar_pro = atype - 1;
194#endif
195		}
196		break;
197
198	default:
199		printf("%s%d: can't handle af%d\n", ifp->if_name, ifp->if_unit,
200		    dst->sa_family);
201		senderr(EAFNOSUPPORT);
202	}
203
204	if (mcopy)
205		(void) if_simloop(ifp, mcopy, dst->sa_family, 0);
206
207	M_PREPEND(m, ARC_HDRLEN, M_DONTWAIT);
208	if (m == 0)
209		senderr(ENOBUFS);
210	ah = mtod(m, struct arc_header *);
211	ah->arc_type = atype;
212	ah->arc_dhost = adst;
213	ah->arc_shost = *IF_LLADDR(ifp);
214
215	if (ifp->if_bpf)
216		bpf_mtap(ifp, m);
217
218#if __FreeBSD_version < 500000
219	s = splimp();
220
221	/*
222	 * Queue message on interface, and start output if interface
223	 * not yet active.
224	 */
225	if (IF_QFULL(&ifp->if_snd)) {
226		IF_DROP(&ifp->if_snd);
227		splx(s);
228		senderr(ENOBUFS);
229	}
230	ifp->if_obytes += m->m_pkthdr.len;
231	IF_ENQUEUE(&ifp->if_snd, m);
232	if ((ifp->if_flags & IFF_OACTIVE) == 0)
233		(*ifp->if_start)(ifp);
234	splx(s);
235#else
236	if (!IF_HANDOFF(&ifp->if_snd, m, ifp)) {
237		m = 0;
238		senderr(ENOBUFS);
239	}
240#endif
241
242	return (error);
243
244bad:
245	if (m)
246		m_freem(m);
247	return (error);
248}
249
250void
251arc_frag_init(ifp)
252	struct ifnet *ifp;
253{
254	struct arccom *ac;
255
256	ac = (struct arccom *)ifp;
257	ac->curr_frag = 0;
258}
259
260struct mbuf *
261arc_frag_next(ifp)
262	struct ifnet *ifp;
263{
264	struct arccom *ac;
265	struct mbuf *m;
266	struct arc_header *ah;
267
268	ac = (struct arccom *)ifp;
269	if ((m = ac->curr_frag) == 0) {
270		int tfrags;
271
272		/* dequeue new packet */
273		IF_DEQUEUE(&ifp->if_snd, m);
274		if (m == 0)
275			return 0;
276
277		ah = mtod(m, struct arc_header *);
278		if (!arc_isphds(ah->arc_type))
279			return m;
280
281		++ac->ac_seqid;		/* make the seqid unique */
282		tfrags = (m->m_pkthdr.len + 503) / 504;
283		ac->fsflag = 2 * tfrags - 3;
284		ac->sflag = 0;
285		ac->rsflag = ac->fsflag;
286		ac->arc_dhost = ah->arc_dhost;
287		ac->arc_shost = ah->arc_shost;
288		ac->arc_type = ah->arc_type;
289
290		m_adj(m, ARC_HDRLEN);
291		ac->curr_frag = m;
292	}
293
294	/* split out next fragment and return it */
295	if (ac->sflag < ac->fsflag) {
296		/* we CAN'T have short packets here */
297		ac->curr_frag = m_split(m, 504, M_DONTWAIT);
298		if (ac->curr_frag == 0) {
299			m_freem(m);
300			return 0;
301		}
302
303		M_PREPEND(m, ARC_HDRNEWLEN, M_DONTWAIT);
304		if (m == 0) {
305			m_freem(ac->curr_frag);
306			ac->curr_frag = 0;
307			return 0;
308		}
309
310		ah = mtod(m, struct arc_header *);
311		ah->arc_flag = ac->rsflag;
312		ah->arc_seqid = ac->ac_seqid;
313
314		ac->sflag += 2;
315		ac->rsflag = ac->sflag;
316	} else if ((m->m_pkthdr.len >=
317	    ARC_MIN_FORBID_LEN - ARC_HDRNEWLEN + 2) &&
318	    (m->m_pkthdr.len <=
319	    ARC_MAX_FORBID_LEN - ARC_HDRNEWLEN + 2)) {
320		ac->curr_frag = 0;
321
322		M_PREPEND(m, ARC_HDRNEWLEN_EXC, M_DONTWAIT);
323		if (m == 0)
324			return 0;
325
326		ah = mtod(m, struct arc_header *);
327		ah->arc_flag = 0xFF;
328		ah->arc_seqid = 0xFFFF;
329		ah->arc_type2 = ac->arc_type;
330		ah->arc_flag2 = ac->sflag;
331		ah->arc_seqid2 = ac->ac_seqid;
332	} else {
333		ac->curr_frag = 0;
334
335		M_PREPEND(m, ARC_HDRNEWLEN, M_DONTWAIT);
336		if (m == 0)
337			return 0;
338
339		ah = mtod(m, struct arc_header *);
340		ah->arc_flag = ac->sflag;
341		ah->arc_seqid = ac->ac_seqid;
342	}
343
344	ah->arc_dhost = ac->arc_dhost;
345	ah->arc_shost = ac->arc_shost;
346	ah->arc_type = ac->arc_type;
347
348	return m;
349}
350
351/*
352 * Defragmenter. Returns mbuf if last packet found, else
353 * NULL. frees imcoming mbuf as necessary.
354 */
355
356static __inline struct mbuf *
357arc_defrag(ifp, m)
358	struct ifnet *ifp;
359	struct mbuf *m;
360{
361	struct arc_header *ah, *ah1;
362	struct arccom *ac;
363	struct ac_frag *af;
364	struct mbuf *m1;
365	char *s;
366	int newflen;
367	u_char src,dst,typ;
368
369	ac = (struct arccom *)ifp;
370
371	if (m->m_len < ARC_HDRNEWLEN) {
372		m = m_pullup(m, ARC_HDRNEWLEN);
373		if (m == NULL) {
374			++ifp->if_ierrors;
375			return NULL;
376		}
377	}
378
379	ah = mtod(m, struct arc_header *);
380	typ = ah->arc_type;
381
382	if (!arc_isphds(typ))
383		return m;
384
385	src = ah->arc_shost;
386	dst = ah->arc_dhost;
387
388	if (ah->arc_flag == 0xff) {
389		m_adj(m, 4);
390
391		if (m->m_len < ARC_HDRNEWLEN) {
392			m = m_pullup(m, ARC_HDRNEWLEN);
393			if (m == NULL) {
394				++ifp->if_ierrors;
395				return NULL;
396			}
397		}
398
399		ah = mtod(m, struct arc_header *);
400	}
401
402	af = &ac->ac_fragtab[src];
403	m1 = af->af_packet;
404	s = "debug code error";
405
406	if (ah->arc_flag & 1) {
407		/*
408		 * first fragment. We always initialize, which is
409		 * about the right thing to do, as we only want to
410		 * accept one fragmented packet per src at a time.
411		 */
412		if (m1 != NULL)
413			m_freem(m1);
414
415		af->af_packet = m;
416		m1 = m;
417		af->af_maxflag = ah->arc_flag;
418		af->af_lastseen = 0;
419		af->af_seqid = ah->arc_seqid;
420
421		return NULL;
422		/* notreached */
423	} else {
424		/* check for unfragmented packet */
425		if (ah->arc_flag == 0)
426			return m;
427
428		/* do we have a first packet from that src? */
429		if (m1 == NULL) {
430			s = "no first frag";
431			goto outofseq;
432		}
433
434		ah1 = mtod(m1, struct arc_header *);
435
436		if (ah->arc_seqid != ah1->arc_seqid) {
437			s = "seqid differs";
438			goto outofseq;
439		}
440
441		if (typ != ah1->arc_type) {
442			s = "type differs";
443			goto outofseq;
444		}
445
446		if (dst != ah1->arc_dhost) {
447			s = "dest host differs";
448			goto outofseq;
449		}
450
451		/* typ, seqid and dst are ok here. */
452
453		if (ah->arc_flag == af->af_lastseen) {
454			m_freem(m);
455			return NULL;
456		}
457
458		if (ah->arc_flag == af->af_lastseen + 2) {
459			/* ok, this is next fragment */
460			af->af_lastseen = ah->arc_flag;
461			m_adj(m,ARC_HDRNEWLEN);
462
463			/*
464			 * m_cat might free the first mbuf (with pkthdr)
465			 * in 2nd chain; therefore:
466			 */
467
468			newflen = m->m_pkthdr.len;
469
470			m_cat(m1,m);
471
472			m1->m_pkthdr.len += newflen;
473
474			/* is it the last one? */
475			if (af->af_lastseen > af->af_maxflag) {
476				af->af_packet = NULL;
477				return(m1);
478			} else
479				return NULL;
480		}
481		s = "other reason";
482		/* if all else fails, it is out of sequence, too */
483	}
484outofseq:
485	if (m1) {
486		m_freem(m1);
487		af->af_packet = NULL;
488	}
489
490	if (m)
491		m_freem(m);
492
493	log(LOG_INFO,"%s%d: got out of seq. packet: %s\n",
494	    ifp->if_name, ifp->if_unit, s);
495
496	return NULL;
497}
498
499/*
500 * return 1 if Packet Header Definition Standard, else 0.
501 * For now: old IP, old ARP aren't obviously. Lacking correct information,
502 * we guess that besides new IP and new ARP also IPX and APPLETALK are PHDS.
503 * (Apple and Novell corporations were involved, among others, in PHDS work).
504 * Easiest is to assume that everybody else uses that, too.
505 */
506int
507arc_isphds(type)
508	u_int8_t type;
509{
510	return (type != ARCTYPE_IP_OLD &&
511		type != ARCTYPE_ARP_OLD &&
512		type != ARCTYPE_DIAGNOSE);
513}
514
515/*
516 * Process a received Arcnet packet;
517 * the packet is in the mbuf chain m with
518 * the ARCnet header.
519 */
520void
521arc_input(ifp, m)
522	struct ifnet *ifp;
523	struct mbuf *m;
524{
525	struct arc_header *ah;
526	struct ifqueue *inq;
527	u_int8_t atype;
528#ifdef INET
529	struct arphdr *arph;
530#endif
531#if __FreeBSD_version < 500000
532	int s;
533#endif
534
535	if ((ifp->if_flags & IFF_UP) == 0) {
536		m_freem(m);
537		return;
538	}
539
540	/* possibly defragment: */
541	m = arc_defrag(ifp, m);
542	if (m == NULL)
543		return;
544
545	if (ifp->if_bpf)
546		bpf_mtap(ifp, m);
547
548	ah = mtod(m, struct arc_header *);
549
550	ifp->if_ibytes += m->m_pkthdr.len;
551
552	if (arcbroadcastaddr == ah->arc_dhost) {
553		m->m_flags |= M_BCAST|M_MCAST;
554		ifp->if_imcasts++;
555	}
556
557	atype = ah->arc_type;
558	switch (atype) {
559#ifdef INET
560	case ARCTYPE_IP:
561		m_adj(m, ARC_HDRNEWLEN);
562		schednetisr(NETISR_IP);
563		inq = &ipintrq;
564		break;
565
566	case ARCTYPE_IP_OLD:
567		m_adj(m, ARC_HDRLEN);
568		schednetisr(NETISR_IP);
569		inq = &ipintrq;
570		break;
571
572	case ARCTYPE_ARP:
573		if (ifp->if_flags & IFF_NOARP) {
574			/* Discard packet if ARP is disabled on interface */
575			m_freem(m);
576			return;
577		}
578		m_adj(m, ARC_HDRNEWLEN);
579		schednetisr(NETISR_ARP);
580		inq = &arpintrq;
581#ifdef ARCNET_ALLOW_BROKEN_ARP
582		mtod(m, struct arphdr *)->ar_pro = htons(ETHERTYPE_IP);
583#endif
584		break;
585
586	case ARCTYPE_ARP_OLD:
587		if (ifp->if_flags & IFF_NOARP) {
588			/* Discard packet if ARP is disabled on interface */
589			m_freem(m);
590			return;
591		}
592		m_adj(m, ARC_HDRLEN);
593		schednetisr(NETISR_ARP);
594		inq = &arpintrq;
595		arph = mtod(m, struct arphdr *);
596#ifdef ARCNET_ALLOW_BROKEN_ARP
597		mtod(m, struct arphdr *)->ar_pro = htons(ETHERTYPE_IP);
598#endif
599		break;
600#endif
601#ifdef INET6
602	case ARCTYPE_INET6:
603		m_adj(m, ARC_HDRNEWLEN);
604		schednetisr(NETISR_IPV6);
605		inq = &ip6intrq;
606		break;
607#endif
608	default:
609		m_freem(m);
610		return;
611	}
612
613#if __FreeBSD_version < 500000
614	s = splimp();
615	if (IF_QFULL(inq)) {
616		IF_DROP(inq);
617		m_freem(m);
618	} else
619		IF_ENQUEUE(inq, m);
620	splx(s);
621#else
622	IF_HANDOFF(inq, m, NULL);
623#endif
624}
625
626/*
627 * Convert Arcnet address to printable (loggable) representation.
628 */
629static char digits[] = "0123456789abcdef";
630char *
631arc_sprintf(ap)
632	u_int8_t *ap;
633{
634	static char arcbuf[3];
635	char *cp = arcbuf;
636
637	*cp++ = digits[*ap >> 4];
638	*cp++ = digits[*ap++ & 0xf];
639	*cp   = 0;
640	return (arcbuf);
641}
642
643/*
644 * Register (new) link level address.
645 */
646void
647arc_storelladdr(ifp, lla)
648	struct ifnet *ifp;
649	u_int8_t lla;
650{
651	*IF_LLADDR(ifp) = lla;
652}
653
654/*
655 * Perform common duties while attaching to interface list
656 */
657void
658arc_ifattach(ifp, lla)
659	struct ifnet *ifp;
660	u_int8_t lla;
661{
662	struct ifaddr *ifa;
663	struct sockaddr_dl *sdl;
664	struct arccom *ac;
665
666	if_attach(ifp);
667	ifp->if_type = IFT_ARCNET;
668	ifp->if_addrlen = 1;
669	ifp->if_hdrlen = ARC_HDRLEN;
670	ifp->if_mtu = 1500;
671	if (ifp->if_baudrate == 0)
672		ifp->if_baudrate = 2500000;
673#if __FreeBSD_version < 500000
674	ifa = ifnet_addrs[ifp->if_index - 1];
675#else
676	ifa = ifaddr_byindex(ifp->if_index);
677#endif
678	KASSERT(ifa != NULL, ("%s: no lladdr!\n", __FUNCTION__));
679	sdl = (struct sockaddr_dl *)ifa->ifa_addr;
680	sdl->sdl_type = IFT_ARCNET;
681	sdl->sdl_alen = ifp->if_addrlen;
682
683	if (ifp->if_flags & IFF_BROADCAST)
684		ifp->if_flags |= IFF_MULTICAST|IFF_ALLMULTI;
685
686	ac = (struct arccom *)ifp;
687	ac->ac_seqid = (time_second) & 0xFFFF; /* try to make seqid unique */
688	if (lla == 0) {
689		/* XXX this message isn't entirely clear, to me -- cgd */
690		log(LOG_ERR,"%s%d: link address 0 reserved for broadcasts.  Please change it and ifconfig %s%d down up\n",
691		   ifp->if_name, ifp->if_unit, ifp->if_name, ifp->if_unit);
692	}
693	arc_storelladdr(ifp, lla);
694
695	ifp->if_broadcastaddr = &arcbroadcastaddr;
696
697	bpfattach(ifp, DLT_ARCNET, ARC_HDRLEN);
698}
699
700void
701arc_ifdetach(ifp)
702	struct ifnet *ifp;
703{
704	bpfdetach(ifp);
705	if_detach(ifp);
706}
707
708int
709arc_ioctl(ifp, command, data)
710	struct ifnet *ifp;
711	int command;
712	caddr_t data;
713{
714	struct ifaddr *ifa = (struct ifaddr *) data;
715	struct ifreq *ifr = (struct ifreq *) data;
716	int error = 0;
717
718	switch (command) {
719	case SIOCSIFADDR:
720		ifp->if_flags |= IFF_UP;
721		switch (ifa->ifa_addr->sa_family) {
722#ifdef INET
723		case AF_INET:
724			ifp->if_init(ifp->if_softc);	/* before arpwhohas */
725			arp_ifinit(ifp, ifa);
726			break;
727#endif
728		default:
729			ifp->if_init(ifp->if_softc);
730			break;
731		}
732		break;
733
734	case SIOCADDMULTI:
735	case SIOCDELMULTI:
736		if (ifr == NULL)
737			error = EAFNOSUPPORT;
738		else {
739			switch (ifr->ifr_addr.sa_family) {
740			case AF_INET:
741			case AF_INET6:
742				error = 0;
743				break;
744			default:
745				error = EAFNOSUPPORT;
746				break;
747			}
748		}
749		break;
750
751	case SIOCSIFMTU:
752		/*
753		 * Set the interface MTU.
754		 * mtu can't be larger than ARCMTU for RFC1051
755		 * and can't be larger than ARC_PHDS_MTU
756		 */
757		if (((ifp->if_flags & IFF_LINK0) && ifr->ifr_mtu > ARCMTU) ||
758		    ifr->ifr_mtu > ARC_PHDS_MAXMTU)
759			error = EINVAL;
760		else
761			ifp->if_mtu = ifr->ifr_mtu;
762		break;
763
764#if 0
765	case SIOCGIFADDR:
766		{
767			struct sockaddr *sa;
768
769			sa = (struct sockaddr *) & ifr->ifr_data;
770			bcopy(IFP2AC(ifp)->ac_enaddr,
771			      (caddr_t) sa->sa_data, ETHER_ADDR_LEN);
772		}
773		break;
774#endif
775	}
776
777	return (error);
778}
779