xref: /netbsd-src/sys/net/if_ethersubr.c (revision aaf4ece63a859a04e37cf3a7229b5fab0157cc06)
1 /*	$NetBSD: if_ethersubr.c,v 1.128 2005/12/11 23:05:24 thorpej Exp $	*/
2 
3 /*
4  * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. Neither the name of the project nor the names of its contributors
16  *    may be used to endorse or promote products derived from this software
17  *    without specific prior written permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  */
31 
32 /*
33  * Copyright (c) 1982, 1989, 1993
34  *	The Regents of the University of California.  All rights reserved.
35  *
36  * Redistribution and use in source and binary forms, with or without
37  * modification, are permitted provided that the following conditions
38  * are met:
39  * 1. Redistributions of source code must retain the above copyright
40  *    notice, this list of conditions and the following disclaimer.
41  * 2. Redistributions in binary form must reproduce the above copyright
42  *    notice, this list of conditions and the following disclaimer in the
43  *    documentation and/or other materials provided with the distribution.
44  * 3. Neither the name of the University nor the names of its contributors
45  *    may be used to endorse or promote products derived from this software
46  *    without specific prior written permission.
47  *
48  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
49  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
50  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
51  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
52  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
53  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
54  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
55  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
56  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
57  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
58  * SUCH DAMAGE.
59  *
60  *	@(#)if_ethersubr.c	8.2 (Berkeley) 4/4/96
61  */
62 
63 #include <sys/cdefs.h>
64 __KERNEL_RCSID(0, "$NetBSD: if_ethersubr.c,v 1.128 2005/12/11 23:05:24 thorpej Exp $");
65 
66 #include "opt_inet.h"
67 #include "opt_atalk.h"
68 #include "opt_ccitt.h"
69 #include "opt_llc.h"
70 #include "opt_iso.h"
71 #include "opt_ipx.h"
72 #include "opt_mbuftrace.h"
73 #include "opt_ns.h"
74 #include "opt_gateway.h"
75 #include "opt_pfil_hooks.h"
76 #include "vlan.h"
77 #include "pppoe.h"
78 #include "bridge.h"
79 #include "bpfilter.h"
80 #include "arp.h"
81 #include "agr.h"
82 
83 #include <sys/param.h>
84 #include <sys/systm.h>
85 #include <sys/kernel.h>
86 #include <sys/callout.h>
87 #include <sys/malloc.h>
88 #include <sys/mbuf.h>
89 #include <sys/protosw.h>
90 #include <sys/socket.h>
91 #include <sys/ioctl.h>
92 #include <sys/errno.h>
93 #include <sys/syslog.h>
94 
95 #include <machine/cpu.h>
96 
97 #include <net/if.h>
98 #include <net/netisr.h>
99 #include <net/route.h>
100 #include <net/if_llc.h>
101 #include <net/if_dl.h>
102 #include <net/if_types.h>
103 
104 #if NARP == 0
105 /*
106  * XXX there should really be a way to issue this warning from within config(8)
107  */
108 #error You have included NETATALK or a pseudo-device in your configuration that depends on the presence of ethernet interfaces, but have no such interfaces configured. Check if you really need pseudo-device bridge, pppoe, vlan or options NETATALK.
109 #endif
110 
111 #if NBPFILTER > 0
112 #include <net/bpf.h>
113 #endif
114 
115 #include <net/if_ether.h>
116 #if NVLAN > 0
117 #include <net/if_vlanvar.h>
118 #endif
119 
120 #if NPPPOE > 0
121 #include <net/if_pppoe.h>
122 #endif
123 
124 #if NAGR > 0
125 #include <net/agr/ieee8023_slowprotocols.h>	/* XXX */
126 #include <net/agr/ieee8023ad.h>
127 #include <net/agr/if_agrvar.h>
128 #endif
129 
130 #if NBRIDGE > 0
131 #include <net/if_bridgevar.h>
132 #endif
133 
134 #include <netinet/in.h>
135 #ifdef INET
136 #include <netinet/in_var.h>
137 #endif
138 #include <netinet/if_inarp.h>
139 
140 #ifdef INET6
141 #ifndef INET
142 #include <netinet/in.h>
143 #endif
144 #include <netinet6/in6_var.h>
145 #include <netinet6/nd6.h>
146 #endif
147 
148 #ifdef NS
149 #include <netns/ns.h>
150 #include <netns/ns_if.h>
151 #endif
152 
153 #ifdef IPX
154 #include <netipx/ipx.h>
155 #include <netipx/ipx_if.h>
156 #endif
157 
158 #ifdef ISO
159 #include <netiso/argo_debug.h>
160 #include <netiso/iso.h>
161 #include <netiso/iso_var.h>
162 #include <netiso/iso_snpac.h>
163 #endif
164 
165 #ifdef LLC
166 #include <netccitt/dll.h>
167 #include <netccitt/llc_var.h>
168 #endif
169 
170 #if defined(LLC) && defined(CCITT)
171 extern struct ifqueue pkintrq;
172 #endif
173 
174 #ifdef NETATALK
175 #include <netatalk/at.h>
176 #include <netatalk/at_var.h>
177 #include <netatalk/at_extern.h>
178 
179 #define llc_snap_org_code llc_un.type_snap.org_code
180 #define llc_snap_ether_type llc_un.type_snap.ether_type
181 
182 extern u_char	at_org_code[3];
183 extern u_char	aarp_org_code[3];
184 #endif /* NETATALK */
185 
186 static struct timeval bigpktppslim_last;
187 static int bigpktppslim = 2;	/* XXX */
188 static int bigpktpps_count;
189 
190 
191 const uint8_t etherbroadcastaddr[ETHER_ADDR_LEN] =
192     { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff };
193 const uint8_t ethermulticastaddr_slowprotocols[ETHER_ADDR_LEN] =
194     { 0x01, 0x80, 0xc2, 0x00, 0x00, 0x02 };
195 #define senderr(e) { error = (e); goto bad;}
196 
197 #define SIN(x) ((struct sockaddr_in *)x)
198 
199 static	int ether_output(struct ifnet *, struct mbuf *,
200 	    struct sockaddr *, struct rtentry *);
201 static	void ether_input(struct ifnet *, struct mbuf *);
202 
203 /*
204  * Ethernet output routine.
205  * Encapsulate a packet of type family for the local net.
206  * Assumes that ifp is actually pointer to ethercom structure.
207  */
208 static int
209 ether_output(struct ifnet *ifp, struct mbuf *m0, struct sockaddr *dst,
210 	struct rtentry *rt0)
211 {
212 	u_int16_t etype = 0;
213 	int error = 0, hdrcmplt = 0;
214  	u_char esrc[6], edst[6];
215 	struct mbuf *m = m0;
216 	struct rtentry *rt;
217 	struct mbuf *mcopy = (struct mbuf *)0;
218 	struct ether_header *eh;
219 	ALTQ_DECL(struct altq_pktattr pktattr;)
220 #ifdef INET
221 	struct arphdr *ah;
222 #endif /* INET */
223 #ifdef NETATALK
224 	struct at_ifaddr *aa;
225 #endif /* NETATALK */
226 
227 #ifdef MBUFTRACE
228 	m_claimm(m, ifp->if_mowner);
229 #endif
230 	if ((ifp->if_flags & (IFF_UP|IFF_RUNNING)) != (IFF_UP|IFF_RUNNING))
231 		senderr(ENETDOWN);
232 	if ((rt = rt0) != NULL) {
233 		if ((rt->rt_flags & RTF_UP) == 0) {
234 			if ((rt0 = rt = rtalloc1(dst, 1)) != NULL) {
235 				rt->rt_refcnt--;
236 				if (rt->rt_ifp != ifp)
237 					return (*rt->rt_ifp->if_output)
238 							(ifp, m0, dst, rt);
239 			} else
240 				senderr(EHOSTUNREACH);
241 		}
242 		if ((rt->rt_flags & RTF_GATEWAY) && dst->sa_family != AF_NS) {
243 			if (rt->rt_gwroute == 0)
244 				goto lookup;
245 			if (((rt = rt->rt_gwroute)->rt_flags & RTF_UP) == 0) {
246 				rtfree(rt); rt = rt0;
247 			lookup: rt->rt_gwroute = rtalloc1(rt->rt_gateway, 1);
248 				if ((rt = rt->rt_gwroute) == 0)
249 					senderr(EHOSTUNREACH);
250 				/* the "G" test below also prevents rt == rt0 */
251 				if ((rt->rt_flags & RTF_GATEWAY) ||
252 				    (rt->rt_ifp != ifp)) {
253 					rt->rt_refcnt--;
254 					rt0->rt_gwroute = 0;
255 					senderr(EHOSTUNREACH);
256 				}
257 			}
258 		}
259 		if (rt->rt_flags & RTF_REJECT)
260 			if (rt->rt_rmx.rmx_expire == 0 ||
261 			    (u_long) time.tv_sec < rt->rt_rmx.rmx_expire)
262 				senderr(rt == rt0 ? EHOSTDOWN : EHOSTUNREACH);
263 	}
264 
265 	switch (dst->sa_family) {
266 
267 #ifdef INET
268 	case AF_INET:
269 		if (m->m_flags & M_BCAST)
270                 	(void)memcpy(edst, etherbroadcastaddr, sizeof(edst));
271 
272 		else if (m->m_flags & M_MCAST) {
273 			ETHER_MAP_IP_MULTICAST(&SIN(dst)->sin_addr,
274 			    (caddr_t)edst)
275 
276 		} else if (!arpresolve(ifp, rt, m, dst, edst))
277 			return (0);	/* if not yet resolved */
278 		/* If broadcasting on a simplex interface, loopback a copy */
279 		if ((m->m_flags & M_BCAST) && (ifp->if_flags & IFF_SIMPLEX))
280 			mcopy = m_copy(m, 0, (int)M_COPYALL);
281 		etype = htons(ETHERTYPE_IP);
282 		break;
283 
284 	case AF_ARP:
285 		ah = mtod(m, struct arphdr *);
286 		if (m->m_flags & M_BCAST)
287                 	(void)memcpy(edst, etherbroadcastaddr, sizeof(edst));
288 		else
289 			bcopy((caddr_t)ar_tha(ah),
290 				(caddr_t)edst, sizeof(edst));
291 
292 		ah->ar_hrd = htons(ARPHRD_ETHER);
293 
294 		switch (ntohs(ah->ar_op)) {
295 		case ARPOP_REVREQUEST:
296 		case ARPOP_REVREPLY:
297 			etype = htons(ETHERTYPE_REVARP);
298 			break;
299 
300 		case ARPOP_REQUEST:
301 		case ARPOP_REPLY:
302 		default:
303 			etype = htons(ETHERTYPE_ARP);
304 		}
305 
306 		break;
307 #endif
308 #ifdef INET6
309 	case AF_INET6:
310 		if (!nd6_storelladdr(ifp, rt, m, dst, (u_char *)edst)){
311 			/* something bad happened */
312 			return (0);
313 		}
314 		etype = htons(ETHERTYPE_IPV6);
315 		break;
316 #endif
317 #ifdef NETATALK
318     case AF_APPLETALK:
319 		if (!aarpresolve(ifp, m, (struct sockaddr_at *)dst, edst)) {
320 #ifdef NETATALKDEBUG
321 			printf("aarpresolv failed\n");
322 #endif /* NETATALKDEBUG */
323 			return (0);
324 		}
325 		/*
326 		 * ifaddr is the first thing in at_ifaddr
327 		 */
328 		aa = (struct at_ifaddr *) at_ifawithnet(
329 		    (struct sockaddr_at *)dst, ifp);
330 		if (aa == NULL)
331 		    goto bad;
332 
333 		/*
334 		 * In the phase 2 case, we need to prepend an mbuf for the
335 		 * llc header.  Since we must preserve the value of m,
336 		 * which is passed to us by value, we m_copy() the first
337 		 * mbuf, and use it for our llc header.
338 		 */
339 		if (aa->aa_flags & AFA_PHASE2) {
340 			struct llc llc;
341 
342 			M_PREPEND(m, sizeof(struct llc), M_DONTWAIT);
343 			llc.llc_dsap = llc.llc_ssap = LLC_SNAP_LSAP;
344 			llc.llc_control = LLC_UI;
345 			bcopy(at_org_code, llc.llc_snap_org_code,
346 			    sizeof(llc.llc_snap_org_code));
347 			llc.llc_snap_ether_type = htons(ETHERTYPE_ATALK);
348 			bcopy(&llc, mtod(m, caddr_t), sizeof(struct llc));
349 		} else {
350 			etype = htons(ETHERTYPE_ATALK);
351 		}
352 		break;
353 #endif /* NETATALK */
354 #ifdef NS
355 	case AF_NS:
356 		etype = htons(ETHERTYPE_NS);
357  		bcopy((caddr_t)&(((struct sockaddr_ns *)dst)->sns_addr.x_host),
358 		    (caddr_t)edst, sizeof (edst));
359 		if (!bcmp((caddr_t)edst, (caddr_t)&ns_thishost, sizeof(edst)))
360 			return (looutput(ifp, m, dst, rt));
361 		/* If broadcasting on a simplex interface, loopback a copy */
362 		if ((m->m_flags & M_BCAST) && (ifp->if_flags & IFF_SIMPLEX))
363 			mcopy = m_copy(m, 0, (int)M_COPYALL);
364 		break;
365 #endif
366 #ifdef IPX
367 	case AF_IPX:
368 		etype = htons(ETHERTYPE_IPX);
369  		bcopy((caddr_t)&(((struct sockaddr_ipx *)dst)->sipx_addr.x_host),
370 		    (caddr_t)edst, sizeof (edst));
371 		/* If broadcasting on a simplex interface, loopback a copy */
372 		if ((m->m_flags & M_BCAST) && (ifp->if_flags & IFF_SIMPLEX))
373 			mcopy = m_copy(m, 0, (int)M_COPYALL);
374 		break;
375 #endif
376 #ifdef	ISO
377 	case AF_ISO: {
378 		int	snpalen;
379 		struct	llc *l;
380 		struct sockaddr_dl *sdl;
381 
382 		if (rt && (sdl = (struct sockaddr_dl *)rt->rt_gateway) &&
383 		    sdl->sdl_family == AF_LINK && sdl->sdl_alen > 0) {
384 			bcopy(LLADDR(sdl), (caddr_t)edst, sizeof(edst));
385 		} else {
386 			error = iso_snparesolve(ifp, (struct sockaddr_iso *)dst,
387 						(char *)edst, &snpalen);
388 			if (error)
389 				goto bad; /* Not Resolved */
390 		}
391 		/* If broadcasting on a simplex interface, loopback a copy */
392 		if (*edst & 1)
393 			m->m_flags |= (M_BCAST|M_MCAST);
394 		if ((m->m_flags & M_BCAST) && (ifp->if_flags & IFF_SIMPLEX) &&
395 		    (mcopy = m_copy(m, 0, (int)M_COPYALL))) {
396 			M_PREPEND(mcopy, sizeof (*eh), M_DONTWAIT);
397 			if (mcopy) {
398 				eh = mtod(mcopy, struct ether_header *);
399 				bcopy((caddr_t)edst,
400 				      (caddr_t)eh->ether_dhost, sizeof (edst));
401 				bcopy(LLADDR(ifp->if_sadl),
402 				      (caddr_t)eh->ether_shost, sizeof (edst));
403 			}
404 		}
405 		M_PREPEND(m, 3, M_DONTWAIT);
406 		if (m == NULL)
407 			return (0);
408 		l = mtod(m, struct llc *);
409 		l->llc_dsap = l->llc_ssap = LLC_ISO_LSAP;
410 		l->llc_control = LLC_UI;
411 #ifdef ARGO_DEBUG
412 		if (argo_debug[D_ETHER]) {
413 			int i;
414 			printf("unoutput: sending pkt to: ");
415 			for (i=0; i<6; i++)
416 				printf("%x ", edst[i] & 0xff);
417 			printf("\n");
418 		}
419 #endif
420 		} break;
421 #endif /* ISO */
422 #ifdef	LLC
423 /*	case AF_NSAP: */
424 	case AF_CCITT: {
425 		struct sockaddr_dl *sdl =
426 			(struct sockaddr_dl *) rt -> rt_gateway;
427 
428 		if (sdl && sdl->sdl_family == AF_LINK
429 		    && sdl->sdl_alen > 0) {
430 			bcopy(LLADDR(sdl), (char *)edst,
431 				sizeof(edst));
432 		} else goto bad; /* Not a link interface ? Funny ... */
433 		if ((ifp->if_flags & IFF_SIMPLEX) && (*edst & 1) &&
434 		    (mcopy = m_copy(m, 0, (int)M_COPYALL))) {
435 			M_PREPEND(mcopy, sizeof (*eh), M_DONTWAIT);
436 			if (mcopy) {
437 				eh = mtod(mcopy, struct ether_header *);
438 				bcopy((caddr_t)edst,
439 				      (caddr_t)eh->ether_dhost, sizeof (edst));
440 				bcopy(LLADDR(ifp->if_sadl),
441 				      (caddr_t)eh->ether_shost, sizeof (edst));
442 			}
443 		}
444 #ifdef LLC_DEBUG
445 		{
446 			int i;
447 			struct llc *l = mtod(m, struct llc *);
448 
449 			printf("ether_output: sending LLC2 pkt to: ");
450 			for (i=0; i<6; i++)
451 				printf("%x ", edst[i] & 0xff);
452 			printf(" len 0x%x dsap 0x%x ssap 0x%x control 0x%x\n",
453 			    m->m_pkthdr.len, l->llc_dsap & 0xff, l->llc_ssap &0xff,
454 			    l->llc_control & 0xff);
455 
456 		}
457 #endif /* LLC_DEBUG */
458 		} break;
459 #endif /* LLC */
460 
461 	case pseudo_AF_HDRCMPLT:
462 		hdrcmplt = 1;
463 		eh = (struct ether_header *)dst->sa_data;
464 		bcopy((caddr_t)eh->ether_shost, (caddr_t)esrc, sizeof (esrc));
465 		/* FALLTHROUGH */
466 
467 	case AF_UNSPEC:
468 		eh = (struct ether_header *)dst->sa_data;
469  		bcopy((caddr_t)eh->ether_dhost, (caddr_t)edst, sizeof (edst));
470 		/* AF_UNSPEC doesn't swap the byte order of the ether_type. */
471 		etype = eh->ether_type;
472 		break;
473 
474 	default:
475 		printf("%s: can't handle af%d\n", ifp->if_xname,
476 			dst->sa_family);
477 		senderr(EAFNOSUPPORT);
478 	}
479 
480 	if (mcopy)
481 		(void) looutput(ifp, mcopy, dst, rt);
482 
483 	/* If no ether type is set, this must be a 802.2 formatted packet.
484 	 */
485 	if (etype == 0)
486 		etype = htons(m->m_pkthdr.len);
487 	/*
488 	 * Add local net header.  If no space in first mbuf,
489 	 * allocate another.
490 	 */
491 	M_PREPEND(m, sizeof (struct ether_header), M_DONTWAIT);
492 	if (m == 0)
493 		senderr(ENOBUFS);
494 	eh = mtod(m, struct ether_header *);
495 	/* Note: etype is already in network byte order. */
496 #ifdef __NO_STRICT_ALIGNMENT
497 	eh->ether_type = etype;
498 #else
499 	{
500 		uint8_t *dstp = (uint8_t *) &eh->ether_type;
501 #if BYTE_ORDER == BIG_ENDIAN
502 		dstp[0] = etype >> 8;
503 		dstp[1] = etype;
504 #else
505 		dstp[0] = etype;
506 		dstp[1] = etype >> 8;
507 #endif /* BYTE_ORDER == BIG_ENDIAN */
508 	}
509 #endif /* __NO_STRICT_ALIGNMENT */
510  	bcopy((caddr_t)edst, (caddr_t)eh->ether_dhost, sizeof (edst));
511 	if (hdrcmplt)
512 		bcopy((caddr_t)esrc, (caddr_t)eh->ether_shost,
513 		    sizeof(eh->ether_shost));
514 	else
515 	 	bcopy(LLADDR(ifp->if_sadl), (caddr_t)eh->ether_shost,
516 		    sizeof(eh->ether_shost));
517 
518 #ifdef PFIL_HOOKS
519 	if ((error = pfil_run_hooks(&ifp->if_pfil, &m, ifp, PFIL_OUT)) != 0)
520 		return (error);
521 	if (m == NULL)
522 		return (0);
523 #endif
524 
525 #if NBRIDGE > 0
526 	/*
527 	 * Bridges require special output handling.
528 	 */
529 	if (ifp->if_bridge)
530 		return (bridge_output(ifp, m, NULL, NULL));
531 #endif
532 
533 #ifdef ALTQ
534 	/*
535 	 * If ALTQ is enabled on the parent interface, do
536 	 * classification; the queueing discipline might not
537 	 * require classification, but might require the
538 	 * address family/header pointer in the pktattr.
539 	 */
540 	if (ALTQ_IS_ENABLED(&ifp->if_snd))
541 		altq_etherclassify(&ifp->if_snd, m, &pktattr);
542 #endif
543 
544 	return ifq_enqueue(ifp, m ALTQ_COMMA ALTQ_DECL(&pktattr));
545 
546 bad:
547 	if (m)
548 		m_freem(m);
549 	return (error);
550 }
551 
552 #ifdef ALTQ
553 /*
554  * This routine is a slight hack to allow a packet to be classified
555  * if the Ethernet headers are present.  It will go away when ALTQ's
556  * classification engine understands link headers.
557  */
558 void
559 altq_etherclassify(struct ifaltq *ifq, struct mbuf *m,
560     struct altq_pktattr *pktattr)
561 {
562 	struct ether_header *eh;
563 	u_int16_t ether_type;
564 	int hlen, af, hdrsize;
565 	caddr_t hdr;
566 
567 	hlen = ETHER_HDR_LEN;
568 	eh = mtod(m, struct ether_header *);
569 
570 	ether_type = htons(eh->ether_type);
571 
572 	if (ether_type < ETHERMTU) {
573 		/* LLC/SNAP */
574 		struct llc *llc = (struct llc *)(eh + 1);
575 		hlen += 8;
576 
577 		if (m->m_len < hlen ||
578 		    llc->llc_dsap != LLC_SNAP_LSAP ||
579 		    llc->llc_ssap != LLC_SNAP_LSAP ||
580 		    llc->llc_control != LLC_UI) {
581 			/* Not SNAP. */
582 			goto bad;
583 		}
584 
585 		ether_type = htons(llc->llc_un.type_snap.ether_type);
586 	}
587 
588 	switch (ether_type) {
589 	case ETHERTYPE_IP:
590 		af = AF_INET;
591 		hdrsize = 20;		/* sizeof(struct ip) */
592 		break;
593 
594 	case ETHERTYPE_IPV6:
595 		af = AF_INET6;
596 		hdrsize = 40;		/* sizeof(struct ip6_hdr) */
597 		break;
598 
599 	default:
600 		af = AF_UNSPEC;
601 		hdrsize = 0;
602 		break;
603 	}
604 
605 	while (m->m_len <= hlen) {
606 		hlen -= m->m_len;
607 		m = m->m_next;
608 	}
609 	if (m->m_len < (hlen + hdrsize)) {
610 		/*
611 		 * protocol header not in a single mbuf.
612 		 * We can't cope with this situation right
613 		 * now (but it shouldn't ever happen, really, anyhow).
614 		 */
615 #ifdef DEBUG
616 		printf("altq_etherclassify: headers span multiple mbufs: "
617 		    "%d < %d\n", m->m_len, (hlen + hdrsize));
618 #endif
619 		goto bad;
620 	}
621 
622 	m->m_data += hlen;
623 	m->m_len -= hlen;
624 
625 	hdr = mtod(m, caddr_t);
626 
627 	if (ALTQ_NEEDS_CLASSIFY(ifq))
628 		pktattr->pattr_class =
629 		    (*ifq->altq_classify)(ifq->altq_clfier, m, af);
630 	pktattr->pattr_af = af;
631 	pktattr->pattr_hdr = hdr;
632 
633 	m->m_data -= hlen;
634 	m->m_len += hlen;
635 
636 	return;
637 
638  bad:
639 	pktattr->pattr_class = NULL;
640 	pktattr->pattr_hdr = NULL;
641 	pktattr->pattr_af = AF_UNSPEC;
642 }
643 #endif /* ALTQ */
644 
645 /*
646  * Process a received Ethernet packet;
647  * the packet is in the mbuf chain m with
648  * the ether header.
649  */
650 static void
651 ether_input(struct ifnet *ifp, struct mbuf *m)
652 {
653 	struct ethercom *ec = (struct ethercom *) ifp;
654 	struct ifqueue *inq;
655 	u_int16_t etype;
656 	struct ether_header *eh;
657 #if defined (ISO) || defined (LLC) || defined(NETATALK)
658 	struct llc *l;
659 #endif
660 
661 	if ((ifp->if_flags & IFF_UP) == 0) {
662 		m_freem(m);
663 		return;
664 	}
665 
666 #ifdef MBUFTRACE
667 	m_claimm(m, &ec->ec_rx_mowner);
668 #endif
669 	eh = mtod(m, struct ether_header *);
670 	etype = ntohs(eh->ether_type);
671 
672 	/*
673 	 * Determine if the packet is within its size limits.
674 	 */
675 	if (m->m_pkthdr.len >
676 	    ETHER_MAX_FRAME(ifp, etype, m->m_flags & M_HASFCS)) {
677 		if (ppsratecheck(&bigpktppslim_last, &bigpktpps_count,
678 			    bigpktppslim)) {
679 			printf("%s: discarding oversize frame (len=%d)\n",
680 			    ifp->if_xname, m->m_pkthdr.len);
681 		}
682 		m_freem(m);
683 		return;
684 	}
685 
686 	if (ETHER_IS_MULTICAST(eh->ether_dhost)) {
687 		/*
688 		 * If this is not a simplex interface, drop the packet
689 		 * if it came from us.
690 		 */
691 		if ((ifp->if_flags & IFF_SIMPLEX) == 0 &&
692 		    memcmp(LLADDR(ifp->if_sadl), eh->ether_shost,
693 		    ETHER_ADDR_LEN) == 0) {
694 			m_freem(m);
695 			return;
696 		}
697 
698 		if (memcmp(etherbroadcastaddr,
699 		    eh->ether_dhost, ETHER_ADDR_LEN) == 0)
700 			m->m_flags |= M_BCAST;
701 		else
702 			m->m_flags |= M_MCAST;
703 		ifp->if_imcasts++;
704 	}
705 
706 	/* If the CRC is still on the packet, trim it off. */
707 	if (m->m_flags & M_HASFCS) {
708 		m_adj(m, -ETHER_CRC_LEN);
709 		m->m_flags &= ~M_HASFCS;
710 	}
711 
712 	ifp->if_ibytes += m->m_pkthdr.len;
713 
714 #if NBRIDGE > 0
715 	/*
716 	 * Tap the packet off here for a bridge.  bridge_input()
717 	 * will return NULL if it has consumed the packet, otherwise
718 	 * it gets processed as normal.  Note that bridge_input()
719 	 * will always return the original packet if we need to
720 	 * process it locally.
721 	 */
722 	if (ifp->if_bridge) {
723 		if(m->m_flags & M_PROTO1) {
724 			m->m_flags &= ~M_PROTO1;
725 		} else {
726 			/* clear M_PROMISC, in case the packets comes from a vlan */
727 			m->m_flags &= ~M_PROMISC;
728 			m = bridge_input(ifp, m);
729 			if (m == NULL)
730 				return;
731 
732 			/*
733 			 * Bridge has determined that the packet is for us.
734 			 * Update our interface pointer -- we may have had
735 			 * to "bridge" the packet locally.
736 			 */
737 			ifp = m->m_pkthdr.rcvif;
738 		}
739 	} else
740 #endif /* NBRIDGE > 0 */
741 	{
742 		if ((m->m_flags & (M_BCAST|M_MCAST)) == 0 &&
743 		    (ifp->if_flags & IFF_PROMISC) != 0 &&
744 		    memcmp(LLADDR(ifp->if_sadl), eh->ether_dhost,
745 			   ETHER_ADDR_LEN) != 0) {
746 			m->m_flags |= M_PROMISC;
747 		}
748 	}
749 
750 #ifdef PFIL_HOOKS
751 	if ((m->m_flags & M_PROMISC) == 0) {
752 		if (pfil_run_hooks(&ifp->if_pfil, &m, ifp, PFIL_IN) != 0)
753 			return;
754 		if (m == NULL)
755 			return;
756 
757 		eh = mtod(m, struct ether_header *);
758 		etype = ntohs(eh->ether_type);
759 	}
760 #endif
761 
762 	/*
763 	 * If VLANs are configured on the interface, check to
764 	 * see if the device performed the decapsulation and
765 	 * provided us with the tag.
766 	 */
767 	if (ec->ec_nvlans && m_tag_find(m, PACKET_TAG_VLAN, NULL) != NULL) {
768 #if NVLAN > 0
769 		/*
770 		 * vlan_input() will either recursively call ether_input()
771 		 * or drop the packet.
772 		 */
773 		vlan_input(ifp, m);
774 #else
775 		m_freem(m);
776 #endif
777 		return;
778 	}
779 
780 #if NAGR > 0
781 	if (ifp->if_agrprivate &&
782 	    __predict_true(etype != ETHERTYPE_SLOWPROTOCOLS)) {
783 		m->m_flags &= ~M_PROMISC;
784 		agr_input(ifp, m);
785 		return;
786 	}
787 #endif /* NAGR > 0 */
788 
789 	/*
790 	 * Handle protocols that expect to have the Ethernet header
791 	 * (and possibly FCS) intact.
792 	 */
793 	switch (etype) {
794 #if NVLAN > 0
795 	case ETHERTYPE_VLAN:
796 		/*
797 		 * vlan_input() will either recursively call ether_input()
798 		 * or drop the packet.
799 		 */
800 		if (((struct ethercom *)ifp)->ec_nvlans != 0)
801 			vlan_input(ifp, m);
802 		else
803 			m_freem(m);
804 		return;
805 #endif /* NVLAN > 0 */
806 #if NPPPOE > 0
807 	case ETHERTYPE_PPPOEDISC:
808 	case ETHERTYPE_PPPOE:
809 		if (m->m_flags & M_PROMISC) {
810 			m_freem(m);
811 			return;
812 		}
813 #ifndef PPPOE_SERVER
814 		if (m->m_flags & (M_MCAST | M_BCAST)) {
815 			m_freem(m);
816 			return;
817 		}
818 #endif
819 
820 		if (etype == ETHERTYPE_PPPOEDISC)
821 			inq = &ppoediscinq;
822 		else
823 			inq = &ppoeinq;
824 		if (IF_QFULL(inq)) {
825 			IF_DROP(inq);
826 			m_freem(m);
827 		} else
828 			IF_ENQUEUE(inq, m);
829 #ifndef __HAVE_GENERIC_SOFT_INTERRUPTS
830 		if (!callout_pending(&pppoe_softintr))
831 			callout_reset(&pppoe_softintr, 1, pppoe_softintr_handler, NULL);
832 #else
833 		softintr_schedule(pppoe_softintr);
834 #endif
835 		return;
836 #endif /* NPPPOE > 0 */
837 	case ETHERTYPE_SLOWPROTOCOLS: {
838 		uint8_t subtype;
839 
840 #if defined(DIAGNOSTIC)
841 		if (m->m_pkthdr.len < sizeof(*eh) + sizeof(subtype)) {
842 			panic("ether_input: too short slow protocol packet");
843 		}
844 #endif
845 		m_copydata(m, sizeof(*eh), sizeof(subtype), &subtype);
846 		switch (subtype) {
847 #if NAGR > 0
848 		case SLOWPROTOCOLS_SUBTYPE_LACP:
849 			if (ifp->if_agrprivate) {
850 				ieee8023ad_lacp_input(ifp, m);
851 				return;
852 			}
853 			break;
854 
855 		case SLOWPROTOCOLS_SUBTYPE_MARKER:
856 			if (ifp->if_agrprivate) {
857 				ieee8023ad_marker_input(ifp, m);
858 				return;
859 			}
860 			break;
861 #endif /* NAGR > 0 */
862 		default:
863 			if (subtype == 0 || subtype > 10) {
864 				/* illegal value */
865 				m_freem(m);
866 				return;
867 			}
868 			/* unknown subtype */
869 			break;
870 		}
871 		/* FALLTHROUGH */
872 	}
873 	default:
874 		if (m->m_flags & M_PROMISC) {
875 			m_freem(m);
876 			return;
877 		}
878 	}
879 
880 	/* Strip off the Ethernet header. */
881 	m_adj(m, sizeof(struct ether_header));
882 
883 	/* If the CRC is still on the packet, trim it off. */
884 	if (m->m_flags & M_HASFCS) {
885 		m_adj(m, -ETHER_CRC_LEN);
886 		m->m_flags &= ~M_HASFCS;
887 	}
888 
889 	switch (etype) {
890 #ifdef INET
891 	case ETHERTYPE_IP:
892 #ifdef GATEWAY
893 		if (ipflow_fastforward(m))
894 			return;
895 #endif
896 		schednetisr(NETISR_IP);
897 		inq = &ipintrq;
898 		break;
899 
900 	case ETHERTYPE_ARP:
901 		schednetisr(NETISR_ARP);
902 		inq = &arpintrq;
903 		break;
904 
905 	case ETHERTYPE_REVARP:
906 		revarpinput(m);	/* XXX queue? */
907 		return;
908 #endif
909 #ifdef INET6
910 	case ETHERTYPE_IPV6:
911 		schednetisr(NETISR_IPV6);
912 		inq = &ip6intrq;
913 		break;
914 #endif
915 #ifdef NS
916 	case ETHERTYPE_NS:
917 		schednetisr(NETISR_NS);
918 		inq = &nsintrq;
919 		break;
920 
921 #endif
922 #ifdef IPX
923 	case ETHERTYPE_IPX:
924 		schednetisr(NETISR_IPX);
925 		inq = &ipxintrq;
926 		break;
927 #endif
928 #ifdef NETATALK
929         case ETHERTYPE_ATALK:
930                 schednetisr(NETISR_ATALK);
931                 inq = &atintrq1;
932                 break;
933         case ETHERTYPE_AARP:
934 		/* probably this should be done with a NETISR as well */
935                 aarpinput(ifp, m); /* XXX */
936                 return;
937 #endif /* NETATALK */
938 	default:
939 #if defined (ISO) || defined (LLC) || defined (NETATALK)
940 		if (etype > ETHERMTU)
941 			goto dropanyway;
942 		l = mtod(m, struct llc *);
943 		switch (l->llc_dsap) {
944 #ifdef NETATALK
945 		case LLC_SNAP_LSAP:
946 			switch (l->llc_control) {
947 			case LLC_UI:
948 				if (l->llc_ssap != LLC_SNAP_LSAP) {
949 					goto dropanyway;
950 				}
951 
952 				if (Bcmp(&(l->llc_snap_org_code)[0],
953 				    at_org_code, sizeof(at_org_code)) == 0 &&
954 				    ntohs(l->llc_snap_ether_type) ==
955 				    ETHERTYPE_ATALK) {
956 					inq = &atintrq2;
957 					m_adj(m, sizeof(struct llc));
958 					schednetisr(NETISR_ATALK);
959 					break;
960 				}
961 
962 				if (Bcmp(&(l->llc_snap_org_code)[0],
963 				    aarp_org_code,
964 				    sizeof(aarp_org_code)) == 0 &&
965 				    ntohs(l->llc_snap_ether_type) ==
966 				    ETHERTYPE_AARP) {
967 					m_adj( m, sizeof(struct llc));
968 					aarpinput(ifp, m); /* XXX */
969 				    return;
970 				}
971 
972 			default:
973 				goto dropanyway;
974 			}
975 			break;
976 #endif /* NETATALK */
977 #ifdef	ISO
978 		case LLC_ISO_LSAP:
979 			switch (l->llc_control) {
980 			case LLC_UI:
981 				/* LLC_UI_P forbidden in class 1 service */
982 				if ((l->llc_dsap == LLC_ISO_LSAP) &&
983 				    (l->llc_ssap == LLC_ISO_LSAP)) {
984 					/* LSAP for ISO */
985 					if (m->m_pkthdr.len > etype)
986 						m_adj(m, etype - m->m_pkthdr.len);
987 					m->m_data += 3;		/* XXX */
988 					m->m_len -= 3;		/* XXX */
989 					m->m_pkthdr.len -= 3;	/* XXX */
990 					M_PREPEND(m, sizeof *eh, M_DONTWAIT);
991 					if (m == 0)
992 						return;
993 					*mtod(m, struct ether_header *) = *eh;
994 #ifdef ARGO_DEBUG
995 					if (argo_debug[D_ETHER])
996 						printf("clnp packet");
997 #endif
998 					schednetisr(NETISR_ISO);
999 					inq = &clnlintrq;
1000 					break;
1001 				}
1002 				goto dropanyway;
1003 
1004 			case LLC_XID:
1005 			case LLC_XID_P:
1006 				if(m->m_len < 6)
1007 					goto dropanyway;
1008 				l->llc_window = 0;
1009 				l->llc_fid = 9;
1010 				l->llc_class = 1;
1011 				l->llc_dsap = l->llc_ssap = 0;
1012 				/* Fall through to */
1013 			case LLC_TEST:
1014 			case LLC_TEST_P:
1015 			{
1016 				struct sockaddr sa;
1017 				struct ether_header *eh2;
1018 				int i;
1019 				u_char c = l->llc_dsap;
1020 
1021 				l->llc_dsap = l->llc_ssap;
1022 				l->llc_ssap = c;
1023 				if (m->m_flags & (M_BCAST | M_MCAST))
1024 					bcopy(LLADDR(ifp->if_sadl),
1025 					      (caddr_t)eh->ether_dhost, 6);
1026 				sa.sa_family = AF_UNSPEC;
1027 				sa.sa_len = sizeof(sa);
1028 				eh2 = (struct ether_header *)sa.sa_data;
1029 				for (i = 0; i < 6; i++) {
1030 					eh2->ether_shost[i] = c =
1031 					    eh->ether_dhost[i];
1032 					eh2->ether_dhost[i] =
1033 					    eh->ether_dhost[i] =
1034 					    eh->ether_shost[i];
1035 					eh->ether_shost[i] = c;
1036 				}
1037 				ifp->if_output(ifp, m, &sa, NULL);
1038 				return;
1039 			}
1040 			default:
1041 				m_freem(m);
1042 				return;
1043 			}
1044 			break;
1045 #endif /* ISO */
1046 #ifdef LLC
1047 		case LLC_X25_LSAP:
1048 		{
1049 			if (m->m_pkthdr.len > etype)
1050 				m_adj(m, etype - m->m_pkthdr.len);
1051 			M_PREPEND(m, sizeof(struct sdl_hdr) , M_DONTWAIT);
1052 			if (m == 0)
1053 				return;
1054 			if ( !sdl_sethdrif(ifp, eh->ether_shost, LLC_X25_LSAP,
1055 					    eh->ether_dhost, LLC_X25_LSAP, 6,
1056 					    mtod(m, struct sdl_hdr *)))
1057 				panic("ETHER cons addr failure");
1058 			mtod(m, struct sdl_hdr *)->sdlhdr_len = etype;
1059 #ifdef LLC_DEBUG
1060 				printf("llc packet\n");
1061 #endif /* LLC_DEBUG */
1062 			schednetisr(NETISR_CCITT);
1063 			inq = &llcintrq;
1064 			break;
1065 		}
1066 #endif /* LLC */
1067 		dropanyway:
1068 		default:
1069 			m_freem(m);
1070 			return;
1071 		}
1072 #else /* ISO || LLC  || NETATALK*/
1073 	    m_freem(m);
1074 	    return;
1075 #endif /* ISO || LLC || NETATALK*/
1076 	}
1077 
1078 	if (IF_QFULL(inq)) {
1079 		IF_DROP(inq);
1080 		m_freem(m);
1081 	} else
1082 		IF_ENQUEUE(inq, m);
1083 }
1084 
1085 /*
1086  * Convert Ethernet address to printable (loggable) representation.
1087  */
1088 char *
1089 ether_sprintf(const u_char *ap)
1090 {
1091 	static char etherbuf[18];
1092 	char *cp = etherbuf;
1093 	int i;
1094 
1095 	for (i = 0; i < 6; i++) {
1096 		*cp++ = hexdigits[*ap >> 4];
1097 		*cp++ = hexdigits[*ap++ & 0xf];
1098 		*cp++ = ':';
1099 	}
1100 	*--cp = 0;
1101 	return (etherbuf);
1102 }
1103 
1104 /*
1105  * Perform common duties while attaching to interface list
1106  */
1107 void
1108 ether_ifattach(struct ifnet *ifp, const u_int8_t *lla)
1109 {
1110 	struct ethercom *ec = (struct ethercom *)ifp;
1111 
1112 	ifp->if_type = IFT_ETHER;
1113 	ifp->if_addrlen = ETHER_ADDR_LEN;
1114 	ifp->if_hdrlen = ETHER_HDR_LEN;
1115 	ifp->if_dlt = DLT_EN10MB;
1116 	ifp->if_mtu = ETHERMTU;
1117 	ifp->if_output = ether_output;
1118 	ifp->if_input = ether_input;
1119 	if (ifp->if_baudrate == 0)
1120 		ifp->if_baudrate = IF_Mbps(10);		/* just a default */
1121 
1122 	if_alloc_sadl(ifp);
1123 	memcpy(LLADDR(ifp->if_sadl), lla, ifp->if_addrlen);
1124 
1125 	LIST_INIT(&ec->ec_multiaddrs);
1126 	ifp->if_broadcastaddr = etherbroadcastaddr;
1127 #if NBPFILTER > 0
1128 	bpfattach(ifp, DLT_EN10MB, sizeof(struct ether_header));
1129 #endif
1130 #ifdef MBUFTRACE
1131 	strlcpy(ec->ec_tx_mowner.mo_name, ifp->if_xname,
1132 	    sizeof(ec->ec_tx_mowner.mo_name));
1133 	strlcpy(ec->ec_tx_mowner.mo_descr, "tx",
1134 	    sizeof(ec->ec_tx_mowner.mo_descr));
1135 	strlcpy(ec->ec_rx_mowner.mo_name, ifp->if_xname,
1136 	    sizeof(ec->ec_rx_mowner.mo_name));
1137 	strlcpy(ec->ec_rx_mowner.mo_descr, "rx",
1138 	    sizeof(ec->ec_rx_mowner.mo_descr));
1139 	MOWNER_ATTACH(&ec->ec_tx_mowner);
1140 	MOWNER_ATTACH(&ec->ec_rx_mowner);
1141 	ifp->if_mowner = &ec->ec_tx_mowner;
1142 #endif
1143 }
1144 
1145 void
1146 ether_ifdetach(struct ifnet *ifp)
1147 {
1148 	struct ethercom *ec = (void *) ifp;
1149 	struct ether_multi *enm;
1150 	int s;
1151 
1152 #if NBRIDGE > 0
1153 	if (ifp->if_bridge)
1154 		bridge_ifdetach(ifp);
1155 #endif
1156 
1157 #if NBPFILTER > 0
1158 	bpfdetach(ifp);
1159 #endif
1160 
1161 #if NVLAN > 0
1162 	if (ec->ec_nvlans)
1163 		vlan_ifdetach(ifp);
1164 #endif
1165 
1166 	s = splnet();
1167 	while ((enm = LIST_FIRST(&ec->ec_multiaddrs)) != NULL) {
1168 		LIST_REMOVE(enm, enm_list);
1169 		free(enm, M_IFMADDR);
1170 		ec->ec_multicnt--;
1171 	}
1172 	splx(s);
1173 
1174 #if 0	/* done in if_detach() */
1175 	if_free_sadl(ifp);
1176 #endif
1177 
1178 	MOWNER_DETACH(&ec->ec_rx_mowner);
1179 	MOWNER_DETACH(&ec->ec_tx_mowner);
1180 }
1181 
1182 #if 0
1183 /*
1184  * This is for reference.  We have a table-driven version
1185  * of the little-endian crc32 generator, which is faster
1186  * than the double-loop.
1187  */
1188 u_int32_t
1189 ether_crc32_le(const u_int8_t *buf, size_t len)
1190 {
1191 	u_int32_t c, crc, carry;
1192 	size_t i, j;
1193 
1194 	crc = 0xffffffffU;	/* initial value */
1195 
1196 	for (i = 0; i < len; i++) {
1197 		c = buf[i];
1198 		for (j = 0; j < 8; j++) {
1199 			carry = ((crc & 0x01) ? 1 : 0) ^ (c & 0x01);
1200 			crc >>= 1;
1201 			c >>= 1;
1202 			if (carry)
1203 				crc = (crc ^ ETHER_CRC_POLY_LE);
1204 		}
1205 	}
1206 
1207 	return (crc);
1208 }
1209 #else
1210 u_int32_t
1211 ether_crc32_le(const u_int8_t *buf, size_t len)
1212 {
1213 	static const u_int32_t crctab[] = {
1214 		0x00000000, 0x1db71064, 0x3b6e20c8, 0x26d930ac,
1215 		0x76dc4190, 0x6b6b51f4, 0x4db26158, 0x5005713c,
1216 		0xedb88320, 0xf00f9344, 0xd6d6a3e8, 0xcb61b38c,
1217 		0x9b64c2b0, 0x86d3d2d4, 0xa00ae278, 0xbdbdf21c
1218 	};
1219 	u_int32_t crc;
1220 	size_t i;
1221 
1222 	crc = 0xffffffffU;	/* initial value */
1223 
1224 	for (i = 0; i < len; i++) {
1225 		crc ^= buf[i];
1226 		crc = (crc >> 4) ^ crctab[crc & 0xf];
1227 		crc = (crc >> 4) ^ crctab[crc & 0xf];
1228 	}
1229 
1230 	return (crc);
1231 }
1232 #endif
1233 
1234 u_int32_t
1235 ether_crc32_be(const u_int8_t *buf, size_t len)
1236 {
1237 	u_int32_t c, crc, carry;
1238 	size_t i, j;
1239 
1240 	crc = 0xffffffffU;	/* initial value */
1241 
1242 	for (i = 0; i < len; i++) {
1243 		c = buf[i];
1244 		for (j = 0; j < 8; j++) {
1245 			carry = ((crc & 0x80000000U) ? 1 : 0) ^ (c & 0x01);
1246 			crc <<= 1;
1247 			c >>= 1;
1248 			if (carry)
1249 				crc = (crc ^ ETHER_CRC_POLY_BE) | carry;
1250 		}
1251 	}
1252 
1253 	return (crc);
1254 }
1255 
1256 #ifdef INET
1257 const uint8_t ether_ipmulticast_min[ETHER_ADDR_LEN] =
1258     { 0x01, 0x00, 0x5e, 0x00, 0x00, 0x00 };
1259 const uint8_t ether_ipmulticast_max[ETHER_ADDR_LEN] =
1260     { 0x01, 0x00, 0x5e, 0x7f, 0xff, 0xff };
1261 #endif
1262 #ifdef INET6
1263 const uint8_t ether_ip6multicast_min[ETHER_ADDR_LEN] =
1264     { 0x33, 0x33, 0x00, 0x00, 0x00, 0x00 };
1265 const uint8_t ether_ip6multicast_max[ETHER_ADDR_LEN] =
1266     { 0x33, 0x33, 0xff, 0xff, 0xff, 0xff };
1267 #endif
1268 
1269 /*
1270  * Convert a sockaddr into an Ethernet address or range of Ethernet
1271  * addresses.
1272  */
1273 int
1274 ether_multiaddr(struct sockaddr *sa, u_int8_t addrlo[ETHER_ADDR_LEN],
1275     u_int8_t addrhi[ETHER_ADDR_LEN])
1276 {
1277 #ifdef INET
1278 	struct sockaddr_in *sin;
1279 #endif /* INET */
1280 #ifdef INET6
1281 	struct sockaddr_in6 *sin6;
1282 #endif /* INET6 */
1283 
1284 	switch (sa->sa_family) {
1285 
1286 	case AF_UNSPEC:
1287 		bcopy(sa->sa_data, addrlo, ETHER_ADDR_LEN);
1288 		bcopy(addrlo, addrhi, ETHER_ADDR_LEN);
1289 		break;
1290 
1291 #ifdef INET
1292 	case AF_INET:
1293 		sin = satosin(sa);
1294 		if (sin->sin_addr.s_addr == INADDR_ANY) {
1295 			/*
1296 			 * An IP address of INADDR_ANY means listen to
1297 			 * or stop listening to all of the Ethernet
1298 			 * multicast addresses used for IP.
1299 			 * (This is for the sake of IP multicast routers.)
1300 			 */
1301 			bcopy(ether_ipmulticast_min, addrlo, ETHER_ADDR_LEN);
1302 			bcopy(ether_ipmulticast_max, addrhi, ETHER_ADDR_LEN);
1303 		}
1304 		else {
1305 			ETHER_MAP_IP_MULTICAST(&sin->sin_addr, addrlo);
1306 			bcopy(addrlo, addrhi, ETHER_ADDR_LEN);
1307 		}
1308 		break;
1309 #endif
1310 #ifdef INET6
1311 	case AF_INET6:
1312 		sin6 = satosin6(sa);
1313 		if (IN6_IS_ADDR_UNSPECIFIED(&sin6->sin6_addr)) {
1314 			/*
1315 			 * An IP6 address of 0 means listen to or stop
1316 			 * listening to all of the Ethernet multicast
1317 			 * address used for IP6.
1318 			 * (This is used for multicast routers.)
1319 			 */
1320 			bcopy(ether_ip6multicast_min, addrlo, ETHER_ADDR_LEN);
1321 			bcopy(ether_ip6multicast_max, addrhi, ETHER_ADDR_LEN);
1322 		} else {
1323 			ETHER_MAP_IPV6_MULTICAST(&sin6->sin6_addr, addrlo);
1324 			bcopy(addrlo, addrhi, ETHER_ADDR_LEN);
1325 		}
1326 		break;
1327 #endif
1328 
1329 	default:
1330 		return (EAFNOSUPPORT);
1331 	}
1332 	return (0);
1333 }
1334 
1335 /*
1336  * Add an Ethernet multicast address or range of addresses to the list for a
1337  * given interface.
1338  */
1339 int
1340 ether_addmulti(struct ifreq *ifr, struct ethercom *ec)
1341 {
1342 	struct ether_multi *enm;
1343 	u_char addrlo[ETHER_ADDR_LEN];
1344 	u_char addrhi[ETHER_ADDR_LEN];
1345 	int s = splnet(), error;
1346 
1347 	error = ether_multiaddr(&ifr->ifr_addr, addrlo, addrhi);
1348 	if (error != 0) {
1349 		splx(s);
1350 		return (error);
1351 	}
1352 
1353 	/*
1354 	 * Verify that we have valid Ethernet multicast addresses.
1355 	 */
1356 	if ((addrlo[0] & 0x01) != 1 || (addrhi[0] & 0x01) != 1) {
1357 		splx(s);
1358 		return (EINVAL);
1359 	}
1360 	/*
1361 	 * See if the address range is already in the list.
1362 	 */
1363 	ETHER_LOOKUP_MULTI(addrlo, addrhi, ec, enm);
1364 	if (enm != NULL) {
1365 		/*
1366 		 * Found it; just increment the reference count.
1367 		 */
1368 		++enm->enm_refcount;
1369 		splx(s);
1370 		return (0);
1371 	}
1372 	/*
1373 	 * New address or range; malloc a new multicast record
1374 	 * and link it into the interface's multicast list.
1375 	 */
1376 	enm = (struct ether_multi *)malloc(sizeof(*enm), M_IFMADDR, M_NOWAIT);
1377 	if (enm == NULL) {
1378 		splx(s);
1379 		return (ENOBUFS);
1380 	}
1381 	bcopy(addrlo, enm->enm_addrlo, 6);
1382 	bcopy(addrhi, enm->enm_addrhi, 6);
1383 	enm->enm_refcount = 1;
1384 	LIST_INSERT_HEAD(&ec->ec_multiaddrs, enm, enm_list);
1385 	ec->ec_multicnt++;
1386 	splx(s);
1387 	/*
1388 	 * Return ENETRESET to inform the driver that the list has changed
1389 	 * and its reception filter should be adjusted accordingly.
1390 	 */
1391 	return (ENETRESET);
1392 }
1393 
1394 /*
1395  * Delete a multicast address record.
1396  */
1397 int
1398 ether_delmulti(struct ifreq *ifr, struct ethercom *ec)
1399 {
1400 	struct ether_multi *enm;
1401 	u_char addrlo[ETHER_ADDR_LEN];
1402 	u_char addrhi[ETHER_ADDR_LEN];
1403 	int s = splnet(), error;
1404 
1405 	error = ether_multiaddr(&ifr->ifr_addr, addrlo, addrhi);
1406 	if (error != 0) {
1407 		splx(s);
1408 		return (error);
1409 	}
1410 
1411 	/*
1412 	 * Look ur the address in our list.
1413 	 */
1414 	ETHER_LOOKUP_MULTI(addrlo, addrhi, ec, enm);
1415 	if (enm == NULL) {
1416 		splx(s);
1417 		return (ENXIO);
1418 	}
1419 	if (--enm->enm_refcount != 0) {
1420 		/*
1421 		 * Still some claims to this record.
1422 		 */
1423 		splx(s);
1424 		return (0);
1425 	}
1426 	/*
1427 	 * No remaining claims to this record; unlink and free it.
1428 	 */
1429 	LIST_REMOVE(enm, enm_list);
1430 	free(enm, M_IFMADDR);
1431 	ec->ec_multicnt--;
1432 	splx(s);
1433 	/*
1434 	 * Return ENETRESET to inform the driver that the list has changed
1435 	 * and its reception filter should be adjusted accordingly.
1436 	 */
1437 	return (ENETRESET);
1438 }
1439 
1440 /*
1441  * Common ioctls for Ethernet interfaces.  Note, we must be
1442  * called at splnet().
1443  */
1444 int
1445 ether_ioctl(struct ifnet *ifp, u_long cmd, caddr_t data)
1446 {
1447 	struct ethercom *ec = (void *) ifp;
1448 	struct ifreq *ifr = (struct ifreq *)data;
1449 	struct ifaddr *ifa = (struct ifaddr *)data;
1450 	int error = 0;
1451 
1452 	switch (cmd) {
1453 	case SIOCSIFADDR:
1454 		ifp->if_flags |= IFF_UP;
1455 		switch (ifa->ifa_addr->sa_family) {
1456 		case AF_LINK:
1457 		    {
1458 			struct sockaddr_dl *sdl =
1459 			    (struct sockaddr_dl *) ifa->ifa_addr;
1460 
1461 			if (sdl->sdl_type != IFT_ETHER ||
1462 			    sdl->sdl_alen != ifp->if_addrlen) {
1463 				error = EINVAL;
1464 				break;
1465 			}
1466 
1467 			memcpy(LLADDR(ifp->if_sadl), LLADDR(sdl),
1468 			    ifp->if_addrlen);
1469 
1470 			/* Set new address. */
1471 			error = (*ifp->if_init)(ifp);
1472 			break;
1473 		    }
1474 #ifdef INET
1475 		case AF_INET:
1476 			if ((ifp->if_flags & IFF_RUNNING) == 0 &&
1477 			    (error = (*ifp->if_init)(ifp)) != 0)
1478 				break;
1479 			arp_ifinit(ifp, ifa);
1480 			break;
1481 #endif /* INET */
1482 #ifdef NS
1483 		case AF_NS:
1484 		    {
1485 			struct ns_addr *ina = &IA_SNS(ifa)->sns_addr;
1486 
1487 			if (ns_nullhost(*ina))
1488 				ina->x_host = *(union ns_host *)
1489 				    LLADDR(ifp->if_sadl);
1490 			else
1491 				memcpy(LLADDR(ifp->if_sadl),
1492 				    ina->x_host.c_host, ifp->if_addrlen);
1493 			/* Set new address. */
1494 			error = (*ifp->if_init)(ifp);
1495 			break;
1496 		    }
1497 #endif /* NS */
1498 		default:
1499 			if ((ifp->if_flags & IFF_RUNNING) == 0)
1500 				error = (*ifp->if_init)(ifp);
1501 			break;
1502 		}
1503 		break;
1504 
1505 	case SIOCGIFADDR:
1506 		memcpy(((struct sockaddr *)&ifr->ifr_data)->sa_data,
1507 		    LLADDR(ifp->if_sadl), ETHER_ADDR_LEN);
1508 		break;
1509 
1510 	case SIOCSIFMTU:
1511 	    {
1512 		int maxmtu;
1513 
1514 		if (ec->ec_capabilities & ETHERCAP_JUMBO_MTU)
1515 			maxmtu = ETHERMTU_JUMBO;
1516 		else
1517 			maxmtu = ETHERMTU;
1518 
1519 		if (ifr->ifr_mtu < ETHERMIN || ifr->ifr_mtu > maxmtu)
1520 			error = EINVAL;
1521 		else {
1522 			ifp->if_mtu = ifr->ifr_mtu;
1523 
1524 			/* Make sure the device notices the MTU change. */
1525 			if (ifp->if_flags & IFF_UP)
1526 				error = (*ifp->if_init)(ifp);
1527 		}
1528 		break;
1529 	    }
1530 
1531 	case SIOCSIFFLAGS:
1532 		if ((ifp->if_flags & (IFF_UP|IFF_RUNNING)) == IFF_RUNNING) {
1533 			/*
1534 			 * If interface is marked down and it is running,
1535 			 * then stop and disable it.
1536 			 */
1537 			(*ifp->if_stop)(ifp, 1);
1538 		} else if ((ifp->if_flags & (IFF_UP|IFF_RUNNING)) == IFF_UP) {
1539 			/*
1540 			 * If interface is marked up and it is stopped, then
1541 			 * start it.
1542 			 */
1543 			error = (*ifp->if_init)(ifp);
1544 		} else if ((ifp->if_flags & IFF_UP) != 0) {
1545 			/*
1546 			 * Reset the interface to pick up changes in any other
1547 			 * flags that affect the hardware state.
1548 			 */
1549 			error = (*ifp->if_init)(ifp);
1550 		}
1551 		break;
1552 
1553 	case SIOCADDMULTI:
1554 		error = ether_addmulti(ifr, ec);
1555 		break;
1556 
1557 	case SIOCDELMULTI:
1558 		error = ether_delmulti(ifr, ec);
1559 		break;
1560 
1561 	default:
1562 		error = ENOTTY;
1563 	}
1564 
1565 	return (error);
1566 }
1567