xref: /dflybsd-src/sys/net/if_ethersubr.c (revision 3641b7cac336b1a276f869505f71996e145378c4)
1 /*
2  * Copyright (c) 1982, 1989, 1993
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. All advertising materials mentioning features or use of this software
14  *    must display the following acknowledgement:
15  *	This product includes software developed by the University of
16  *	California, Berkeley and its contributors.
17  * 4. Neither the name of the University nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  *
33  *	@(#)if_ethersubr.c	8.1 (Berkeley) 6/10/93
34  * $FreeBSD: src/sys/net/if_ethersubr.c,v 1.70.2.33 2003/04/28 15:45:53 archie Exp $
35  * $DragonFly: src/sys/net/if_ethersubr.c,v 1.62 2008/05/28 12:11:13 sephe Exp $
36  */
37 
38 #include "opt_atalk.h"
39 #include "opt_inet.h"
40 #include "opt_inet6.h"
41 #include "opt_ipx.h"
42 #include "opt_netgraph.h"
43 #include "opt_carp.h"
44 #include "opt_ethernet.h"
45 
46 #include <sys/param.h>
47 #include <sys/systm.h>
48 #include <sys/globaldata.h>
49 #include <sys/kernel.h>
50 #include <sys/malloc.h>
51 #include <sys/mbuf.h>
52 #include <sys/msgport.h>
53 #include <sys/socket.h>
54 #include <sys/sockio.h>
55 #include <sys/sysctl.h>
56 #include <sys/thread.h>
57 #include <sys/thread2.h>
58 
59 #include <net/if.h>
60 #include <net/netisr.h>
61 #include <net/route.h>
62 #include <net/if_llc.h>
63 #include <net/if_dl.h>
64 #include <net/if_types.h>
65 #include <net/ifq_var.h>
66 #include <net/bpf.h>
67 #include <net/ethernet.h>
68 #include <net/vlan/if_vlan_ether.h>
69 
70 #if defined(INET) || defined(INET6)
71 #include <netinet/in.h>
72 #include <netinet/in_var.h>
73 #include <netinet/if_ether.h>
74 #include <net/ipfw/ip_fw.h>
75 #include <net/dummynet/ip_dummynet.h>
76 #endif
77 #ifdef INET6
78 #include <netinet6/nd6.h>
79 #endif
80 
81 #ifdef CARP
82 #include <netinet/ip_carp.h>
83 #endif
84 
85 #ifdef IPX
86 #include <netproto/ipx/ipx.h>
87 #include <netproto/ipx/ipx_if.h>
88 int (*ef_inputp)(struct ifnet*, const struct ether_header *eh, struct mbuf *m);
89 int (*ef_outputp)(struct ifnet *ifp, struct mbuf **mp, struct sockaddr *dst,
90 		  short *tp, int *hlen);
91 #endif
92 
93 #ifdef NS
94 #include <netns/ns.h>
95 #include <netns/ns_if.h>
96 ushort ns_nettype;
97 int ether_outputdebug = 0;
98 int ether_inputdebug = 0;
99 #endif
100 
101 #ifdef NETATALK
102 #include <netproto/atalk/at.h>
103 #include <netproto/atalk/at_var.h>
104 #include <netproto/atalk/at_extern.h>
105 
106 #define	llc_snap_org_code	llc_un.type_snap.org_code
107 #define	llc_snap_ether_type	llc_un.type_snap.ether_type
108 
109 extern u_char	at_org_code[3];
110 extern u_char	aarp_org_code[3];
111 #endif /* NETATALK */
112 
113 /* netgraph node hooks for ng_ether(4) */
114 void	(*ng_ether_input_p)(struct ifnet *ifp, struct mbuf **mp);
115 void	(*ng_ether_input_orphan_p)(struct ifnet *ifp,
116 		struct mbuf *m, const struct ether_header *eh);
117 int	(*ng_ether_output_p)(struct ifnet *ifp, struct mbuf **mp);
118 void	(*ng_ether_attach_p)(struct ifnet *ifp);
119 void	(*ng_ether_detach_p)(struct ifnet *ifp);
120 
121 int	(*vlan_input_p)(struct mbuf *, struct mbuf_chain *);
122 
123 static int ether_output(struct ifnet *, struct mbuf *, struct sockaddr *,
124 			struct rtentry *);
125 static void ether_restore_header(struct mbuf **, const struct ether_header *,
126 				 const struct ether_header *);
127 static void ether_demux_chain(struct ifnet *, struct mbuf *,
128 			      struct mbuf_chain *);
129 
130 /*
131  * if_bridge support
132  */
133 struct mbuf *(*bridge_input_p)(struct ifnet *, struct mbuf *);
134 int (*bridge_output_p)(struct ifnet *, struct mbuf *,
135 		       struct sockaddr *, struct rtentry *);
136 void (*bridge_dn_p)(struct mbuf *, struct ifnet *);
137 
138 static int ether_resolvemulti(struct ifnet *, struct sockaddr **,
139 			      struct sockaddr *);
140 
141 const uint8_t etherbroadcastaddr[ETHER_ADDR_LEN] = {
142 	0xff, 0xff, 0xff, 0xff, 0xff, 0xff
143 };
144 
145 #define gotoerr(e) do { error = (e); goto bad; } while (0)
146 #define IFP2AC(ifp) ((struct arpcom *)(ifp))
147 
148 static boolean_t ether_ipfw_chk(struct mbuf **m0, struct ifnet *dst,
149 				struct ip_fw **rule,
150 				const struct ether_header *eh);
151 
152 static int ether_ipfw;
153 static u_int ether_restore_hdr;
154 static u_int ether_prepend_hdr;
155 
156 SYSCTL_DECL(_net_link);
157 SYSCTL_NODE(_net_link, IFT_ETHER, ether, CTLFLAG_RW, 0, "Ethernet");
158 SYSCTL_INT(_net_link_ether, OID_AUTO, ipfw, CTLFLAG_RW,
159 	   &ether_ipfw, 0, "Pass ether pkts through firewall");
160 SYSCTL_UINT(_net_link_ether, OID_AUTO, restore_hdr, CTLFLAG_RW,
161 	    &ether_restore_hdr, 0, "# of ether header restoration");
162 SYSCTL_UINT(_net_link_ether, OID_AUTO, prepend_hdr, CTLFLAG_RW,
163 	    &ether_prepend_hdr, 0,
164 	    "# of ether header restoration which prepends mbuf");
165 
166 /*
167  * Ethernet output routine.
168  * Encapsulate a packet of type family for the local net.
169  * Use trailer local net encapsulation if enough data in first
170  * packet leaves a multiple of 512 bytes of data in remainder.
171  * Assumes that ifp is actually pointer to arpcom structure.
172  */
173 static int
174 ether_output(struct ifnet *ifp, struct mbuf *m, struct sockaddr *dst,
175 	     struct rtentry *rt)
176 {
177 	struct ether_header *eh, *deh;
178 	u_char *edst;
179 	int loop_copy = 0;
180 	int hlen = ETHER_HDR_LEN;	/* link layer header length */
181 	struct arpcom *ac = IFP2AC(ifp);
182 	int error;
183 
184 	ASSERT_NOT_SERIALIZED(ifp->if_serializer);
185 
186 	if (ifp->if_flags & IFF_MONITOR)
187 		gotoerr(ENETDOWN);
188 	if ((ifp->if_flags & (IFF_UP | IFF_RUNNING)) != (IFF_UP | IFF_RUNNING))
189 		gotoerr(ENETDOWN);
190 
191 	M_PREPEND(m, sizeof(struct ether_header), MB_DONTWAIT);
192 	if (m == NULL)
193 		return (ENOBUFS);
194 	eh = mtod(m, struct ether_header *);
195 	edst = eh->ether_dhost;
196 
197 	/*
198 	 * Fill in the destination ethernet address and frame type.
199 	 */
200 	switch (dst->sa_family) {
201 #ifdef INET
202 	case AF_INET:
203 		if (!arpresolve(ifp, rt, m, dst, edst))
204 			return (0);	/* if not yet resolved */
205 		eh->ether_type = htons(ETHERTYPE_IP);
206 		break;
207 #endif
208 #ifdef INET6
209 	case AF_INET6:
210 		if (!nd6_storelladdr(&ac->ac_if, rt, m, dst, edst))
211 			return (0);		/* Something bad happenned. */
212 		eh->ether_type = htons(ETHERTYPE_IPV6);
213 		break;
214 #endif
215 #ifdef IPX
216 	case AF_IPX:
217 		if (ef_outputp != NULL) {
218 			error = ef_outputp(ifp, &m, dst, &eh->ether_type,
219 					   &hlen);
220 			if (error)
221 				goto bad;
222 		} else {
223 			eh->ether_type = htons(ETHERTYPE_IPX);
224 			bcopy(&(((struct sockaddr_ipx *)dst)->sipx_addr.x_host),
225 			      edst, ETHER_ADDR_LEN);
226 		}
227 		break;
228 #endif
229 #ifdef NETATALK
230 	case AF_APPLETALK: {
231 		struct at_ifaddr *aa;
232 
233 		if ((aa = at_ifawithnet((struct sockaddr_at *)dst)) == NULL) {
234 			error = 0;	/* XXX */
235 			goto bad;
236 		}
237 		/*
238 		 * In the phase 2 case, need to prepend an mbuf for
239 		 * the llc header.  Since we must preserve the value
240 		 * of m, which is passed to us by value, we m_copy()
241 		 * the first mbuf, and use it for our llc header.
242 		 */
243 		if (aa->aa_flags & AFA_PHASE2) {
244 			struct llc llc;
245 
246 			M_PREPEND(m, sizeof(struct llc), MB_DONTWAIT);
247 			eh = mtod(m, struct ether_header *);
248 			edst = eh->ether_dhost;
249 			llc.llc_dsap = llc.llc_ssap = LLC_SNAP_LSAP;
250 			llc.llc_control = LLC_UI;
251 			bcopy(at_org_code, llc.llc_snap_org_code,
252 			      sizeof at_org_code);
253 			llc.llc_snap_ether_type = htons(ETHERTYPE_AT);
254 			bcopy(&llc,
255 			      mtod(m, caddr_t) + sizeof(struct ether_header),
256 			      sizeof(struct llc));
257 			eh->ether_type = htons(m->m_pkthdr.len);
258 			hlen = sizeof(struct llc) + ETHER_HDR_LEN;
259 		} else {
260 			eh->ether_type = htons(ETHERTYPE_AT);
261 		}
262 		if (!aarpresolve(ac, m, (struct sockaddr_at *)dst, edst))
263 			return (0);
264 		break;
265 	  }
266 #endif
267 #ifdef NS
268 	case AF_NS:
269 		switch(ns_nettype) {
270 		default:
271 		case 0x8137:	/* Novell Ethernet_II Ethernet TYPE II */
272 			eh->ether_type = 0x8137;
273 			break;
274 		case 0x0:	/* Novell 802.3 */
275 			eh->ether_type = htons(m->m_pkthdr.len);
276 			break;
277 		case 0xe0e0:	/* Novell 802.2 and Token-Ring */
278 			M_PREPEND(m, 3, MB_DONTWAIT);
279 			eh = mtod(m, struct ether_header *);
280 			edst = eh->ether_dhost;
281 			eh->ether_type = htons(m->m_pkthdr.len);
282 			cp = mtod(m, u_char *) + sizeof(struct ether_header);
283 			*cp++ = 0xE0;
284 			*cp++ = 0xE0;
285 			*cp++ = 0x03;
286 			break;
287 		}
288 		bcopy(&(((struct sockaddr_ns *)dst)->sns_addr.x_host), edst,
289 		      ETHER_ADDR_LEN);
290 		/*
291 		 * XXX if ns_thishost is the same as the node's ethernet
292 		 * address then just the default code will catch this anyhow.
293 		 * So I'm not sure if this next clause should be here at all?
294 		 * [JRE]
295 		 */
296 		if (bcmp(edst, &ns_thishost, ETHER_ADDR_LEN) == 0) {
297 			m->m_pkthdr.rcvif = ifp;
298 			netisr_dispatch(NETISR_NS, m);
299 			return (error);
300 		}
301 		if (bcmp(edst, &ns_broadhost, ETHER_ADDR_LEN) == 0)
302 			m->m_flags |= M_BCAST;
303 		break;
304 #endif
305 	case pseudo_AF_HDRCMPLT:
306 	case AF_UNSPEC:
307 		loop_copy = -1; /* if this is for us, don't do it */
308 		deh = (struct ether_header *)dst->sa_data;
309 		memcpy(edst, deh->ether_dhost, ETHER_ADDR_LEN);
310 		eh->ether_type = deh->ether_type;
311 		break;
312 
313 	default:
314 		if_printf(ifp, "can't handle af%d\n", dst->sa_family);
315 		gotoerr(EAFNOSUPPORT);
316 	}
317 
318 	if (dst->sa_family == pseudo_AF_HDRCMPLT)	/* unlikely */
319 		memcpy(eh->ether_shost,
320 		       ((struct ether_header *)dst->sa_data)->ether_shost,
321 		       ETHER_ADDR_LEN);
322 	else
323 		memcpy(eh->ether_shost, ac->ac_enaddr, ETHER_ADDR_LEN);
324 
325 	/*
326 	 * Bridges require special output handling.
327 	 */
328 	if (ifp->if_bridge) {
329 		KASSERT(bridge_output_p != NULL,
330 			("%s: if_bridge not loaded!", __func__));
331 		lwkt_serialize_enter(ifp->if_serializer);
332 		error = bridge_output_p(ifp, m, NULL, NULL);
333 		lwkt_serialize_exit(ifp->if_serializer);
334 		return error;
335 	}
336 
337 	/*
338 	 * If a simplex interface, and the packet is being sent to our
339 	 * Ethernet address or a broadcast address, loopback a copy.
340 	 * XXX To make a simplex device behave exactly like a duplex
341 	 * device, we should copy in the case of sending to our own
342 	 * ethernet address (thus letting the original actually appear
343 	 * on the wire). However, we don't do that here for security
344 	 * reasons and compatibility with the original behavior.
345 	 */
346 	if ((ifp->if_flags & IFF_SIMPLEX) && (loop_copy != -1)) {
347 		int csum_flags = 0;
348 
349 		if (m->m_pkthdr.csum_flags & CSUM_IP)
350 			csum_flags |= (CSUM_IP_CHECKED | CSUM_IP_VALID);
351 		if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA)
352 			csum_flags |= (CSUM_DATA_VALID | CSUM_PSEUDO_HDR);
353 		if ((m->m_flags & M_BCAST) || (loop_copy > 0)) {
354 			struct mbuf *n;
355 
356 			if ((n = m_copypacket(m, MB_DONTWAIT)) != NULL) {
357 				n->m_pkthdr.csum_flags |= csum_flags;
358 				if (csum_flags & CSUM_DATA_VALID)
359 					n->m_pkthdr.csum_data = 0xffff;
360 				if_simloop(ifp, n, dst->sa_family, hlen);
361 			} else
362 				ifp->if_iqdrops++;
363 		} else if (bcmp(eh->ether_dhost, eh->ether_shost,
364 				ETHER_ADDR_LEN) == 0) {
365 			m->m_pkthdr.csum_flags |= csum_flags;
366 			if (csum_flags & CSUM_DATA_VALID)
367 				m->m_pkthdr.csum_data = 0xffff;
368 			if_simloop(ifp, m, dst->sa_family, hlen);
369 			return (0);	/* XXX */
370 		}
371 	}
372 
373 #ifdef CARP
374 	if (ifp->if_carp && (error = carp_output(ifp, m, dst, NULL)))
375 		goto bad;
376 #endif
377 
378 
379 	/* Handle ng_ether(4) processing, if any */
380 	if (ng_ether_output_p != NULL) {
381 		if ((error = (*ng_ether_output_p)(ifp, &m)) != 0)
382 			goto bad;
383 		if (m == NULL)
384 			return (0);
385 	}
386 
387 	/* Continue with link-layer output */
388 	return ether_output_frame(ifp, m);
389 
390 bad:
391 	m_freem(m);
392 	return (error);
393 }
394 
395 /*
396  * Ethernet link layer output routine to send a raw frame to the device.
397  *
398  * This assumes that the 14 byte Ethernet header is present and contiguous
399  * in the first mbuf.
400  */
401 int
402 ether_output_frame(struct ifnet *ifp, struct mbuf *m)
403 {
404 	struct ip_fw *rule = NULL;
405 	int error = 0;
406 	struct altq_pktattr pktattr;
407 	struct m_tag *mtag;
408 
409 	ASSERT_NOT_SERIALIZED(ifp->if_serializer);
410 
411 	/* Extract info from dummynet tag */
412 	mtag = m_tag_find(m, PACKET_TAG_DUMMYNET, NULL);
413 	if (mtag != NULL) {
414 		rule = ((struct dn_pkt *)m_tag_data(mtag))->dn_priv;
415 
416 		m_tag_delete(m, mtag);
417 		mtag = NULL;
418 	}
419 
420 	if (ifq_is_enabled(&ifp->if_snd))
421 		altq_etherclassify(&ifp->if_snd, m, &pktattr);
422 	crit_enter();
423 	if (IPFW_LOADED && ether_ipfw != 0) {
424 		struct ether_header save_eh, *eh;
425 
426 		eh = mtod(m, struct ether_header *);
427 		save_eh = *eh;
428 		m_adj(m, ETHER_HDR_LEN);
429 		if (!ether_ipfw_chk(&m, ifp, &rule, eh)) {
430 			crit_exit();
431 			if (m != NULL) {
432 				m_freem(m);
433 				return ENOBUFS; /* pkt dropped */
434 			} else
435 				return 0;	/* consumed e.g. in a pipe */
436 		}
437 
438 		/* packet was ok, restore the ethernet header */
439 		ether_restore_header(&m, eh, &save_eh);
440 		if (m == NULL) {
441 			crit_exit();
442 			return ENOBUFS;
443 		}
444 	}
445 	crit_exit();
446 
447 	/*
448 	 * Queue message on interface, update output statistics if
449 	 * successful, and start output if interface not yet active.
450 	 */
451 	error = ifq_dispatch(ifp, m, &pktattr);
452 	return (error);
453 }
454 
455 /*
456  * ipfw processing for ethernet packets (in and out).
457  * The second parameter is NULL from ether_demux(), and ifp from
458  * ether_output_frame().
459  */
460 static boolean_t
461 ether_ipfw_chk(struct mbuf **m0, struct ifnet *dst, struct ip_fw **rule,
462 	       const struct ether_header *eh)
463 {
464 	struct ether_header save_eh = *eh;	/* might be a ptr in m */
465 	struct ip_fw_args args;
466 	struct m_tag *mtag;
467 	int i;
468 
469 	if (*rule != NULL && fw_one_pass)
470 		return TRUE; /* dummynet packet, already partially processed */
471 
472 	/*
473 	 * I need some amount of data to be contiguous.
474 	 */
475 	i = min((*m0)->m_pkthdr.len, max_protohdr);
476 	if ((*m0)->m_len < i) {
477 		*m0 = m_pullup(*m0, i);
478 		if (*m0 == NULL)
479 			return FALSE;
480 	}
481 
482 	args.m = *m0;		/* the packet we are looking at		*/
483 	args.oif = dst;		/* destination, if any			*/
484 	if ((mtag = m_tag_find(*m0, PACKET_TAG_IPFW_DIVERT, NULL)) != NULL)
485 		m_tag_delete(*m0, mtag);
486 	args.rule = *rule;	/* matching rule to restart		*/
487 	args.next_hop = NULL;	/* we do not support forward yet	*/
488 	args.eh = &save_eh;	/* MAC header for bridged/MAC packets	*/
489 	i = ip_fw_chk_ptr(&args);
490 	*m0 = args.m;
491 	*rule = args.rule;
492 
493 	if ((i & IP_FW_PORT_DENY_FLAG) || *m0 == NULL)	/* drop */
494 		return FALSE;
495 
496 	if (i == 0)					/* a PASS rule.  */
497 		return TRUE;
498 
499 	if (i & IP_FW_PORT_DYNT_FLAG) {
500 		/*
501 		 * Pass the pkt to dummynet, which consumes it.
502 		 */
503 		struct mbuf *m;
504 
505 		m = *m0;	/* pass the original to dummynet */
506 		*m0 = NULL;	/* and nothing back to the caller */
507 
508 		ether_restore_header(&m, eh, &save_eh);
509 		if (m == NULL)
510 			return FALSE;
511 
512 		ip_fw_dn_io_ptr(m, (i & 0xffff),
513 			dst ? DN_TO_ETH_OUT: DN_TO_ETH_DEMUX, &args);
514 		return FALSE;
515 	}
516 	/*
517 	 * XXX at some point add support for divert/forward actions.
518 	 * If none of the above matches, we have to drop the pkt.
519 	 */
520 	return FALSE;
521 }
522 
523 /*
524  * Process a received Ethernet packet.
525  *
526  * The ethernet header is assumed to be in the mbuf so the caller
527  * MUST MAKE SURE that there are at least sizeof(struct ether_header)
528  * bytes in the first mbuf.
529  *
530  * This allows us to concentrate in one place a bunch of code which
531  * is replicated in all device drivers. Also, many functions called
532  * from ether_input() try to put the eh back into the mbuf, so we
533  * can later propagate the 'contiguous packet' interface to them.
534  *
535  * NOTA BENE: for all drivers "eh" is a pointer into the first mbuf or
536  * cluster, right before m_data. So be very careful when working on m,
537  * as you could destroy *eh !!
538  *
539  * First we perform any link layer operations, then continue to the
540  * upper layers with ether_demux().
541  */
542 void
543 ether_input_chain(struct ifnet *ifp, struct mbuf *m, struct mbuf_chain *chain)
544 {
545 	struct ether_header *eh;
546 
547 	ASSERT_SERIALIZED(ifp->if_serializer);
548 	M_ASSERTPKTHDR(m);
549 
550 	/* Discard packet if interface is not up */
551 	if (!(ifp->if_flags & IFF_UP)) {
552 		m_freem(m);
553 		return;
554 	}
555 
556 	if (m->m_len < sizeof(struct ether_header)) {
557 		/* XXX error in the caller. */
558 		m_freem(m);
559 		return;
560 	}
561 	eh = mtod(m, struct ether_header *);
562 
563 	if (ntohs(eh->ether_type) == ETHERTYPE_VLAN &&
564 	    (m->m_flags & M_VLANTAG) == 0) {
565 		/*
566 		 * Extract vlan tag if hardware does not do it for us
567 		 */
568 		vlan_ether_decap(&m);
569 		if (m == NULL)
570 			return;
571 		eh = mtod(m, struct ether_header *);
572 	}
573 
574 	m->m_pkthdr.rcvif = ifp;
575 
576 	if (ETHER_IS_MULTICAST(eh->ether_dhost)) {
577 		if (bcmp(ifp->if_broadcastaddr, eh->ether_dhost,
578 			 ifp->if_addrlen) == 0)
579 			m->m_flags |= M_BCAST;
580 		else
581 			m->m_flags |= M_MCAST;
582 		ifp->if_imcasts++;
583 	}
584 
585 	ETHER_BPF_MTAP(ifp, m);
586 
587 	ifp->if_ibytes += m->m_pkthdr.len;
588 
589 	if (ifp->if_flags & IFF_MONITOR) {
590 		/*
591 		 * Interface marked for monitoring; discard packet.
592 		 */
593 		 m_freem(m);
594 		 return;
595 	}
596 
597 	/*
598 	 * Tap the packet off here for a bridge.  bridge_input()
599 	 * will return NULL if it has consumed the packet, otherwise
600 	 * it gets processed as normal.  Note that bridge_input()
601 	 * will always return the original packet if we need to
602 	 * process it locally.
603 	 */
604 	if (ifp->if_bridge) {
605 		KASSERT(bridge_input_p != NULL,
606 			("%s: if_bridge not loaded!", __func__));
607 
608 		if(m->m_flags & M_PROTO1) {
609 			m->m_flags &= ~M_PROTO1;
610 		} else {
611 			/* clear M_PROMISC, in case the packets comes from a vlan */
612 			/* m->m_flags &= ~M_PROMISC; */
613 			lwkt_serialize_exit(ifp->if_serializer);
614 			m = (*bridge_input_p)(ifp, m);
615 			lwkt_serialize_enter(ifp->if_serializer);
616 			if (m == NULL)
617 				return;
618 
619 			KASSERT(ifp == m->m_pkthdr.rcvif,
620 				("bridge_input_p changed rcvif\n"));
621 
622 			/* 'm' may be changed by bridge_input_p() */
623 			eh = mtod(m, struct ether_header *);
624 		}
625 	}
626 
627 	/* Handle ng_ether(4) processing, if any */
628 	if (ng_ether_input_p != NULL) {
629 		ng_ether_input_p(ifp, &m);
630 		if (m == NULL)
631 			return;
632 
633 		/* 'm' may be changed by ng_ether_input_p() */
634 		eh = mtod(m, struct ether_header *);
635 	}
636 
637 	/* Continue with upper layer processing */
638 	ether_demux_chain(ifp, m, chain);
639 }
640 
641 void
642 ether_input(struct ifnet *ifp, struct mbuf *m)
643 {
644 	ether_input_chain(ifp, m, NULL);
645 }
646 
647 /*
648  * Upper layer processing for a received Ethernet packet.
649  */
650 static void
651 ether_demux_chain(struct ifnet *ifp, struct mbuf *m, struct mbuf_chain *chain)
652 {
653 	struct ether_header save_eh, *eh;
654 	int isr;
655 	u_short ether_type;
656 	struct ip_fw *rule = NULL;
657 	struct m_tag *mtag;
658 #ifdef NETATALK
659 	struct llc *l;
660 #endif
661 
662 	M_ASSERTPKTHDR(m);
663 	KASSERT(m->m_len >= ETHER_HDR_LEN,
664 		("ether header is no contiguous!\n"));
665 
666 	eh = mtod(m, struct ether_header *);
667 	save_eh = *eh;
668 
669 	/* XXX old crufty stuff, needs to be removed */
670 	m_adj(m, sizeof(struct ether_header));
671 
672 	/* Extract info from dummynet tag */
673 	mtag = m_tag_find(m, PACKET_TAG_DUMMYNET, NULL);
674 	if (mtag != NULL) {
675 		rule = ((struct dn_pkt *)m_tag_data(mtag))->dn_priv;
676 		KKASSERT(ifp == NULL);
677 		ifp = m->m_pkthdr.rcvif;
678 
679 		m_tag_delete(m, mtag);
680 		mtag = NULL;
681 	}
682 	if (rule)	/* packet is passing the second time */
683 		goto post_stats;
684 
685 #ifdef CARP
686 	/*
687          * XXX: Okay, we need to call carp_forus() and - if it is for
688          * us jump over code that does the normal check
689          * "ac_enaddr == ether_dhost". The check sequence is a bit
690          * different from OpenBSD, so we jump over as few code as
691          * possible, to catch _all_ sanity checks. This needs
692          * evaluation, to see if the carp ether_dhost values break any
693          * of these checks!
694          */
695 	if (ifp->if_carp && carp_forus(ifp->if_carp, eh->ether_dhost))
696 		goto post_stats;
697 #endif
698 
699 	/*
700 	 * Discard packet if upper layers shouldn't see it because
701 	 * it was unicast to a different Ethernet address.  If the
702 	 * driver is working properly, then this situation can only
703 	 * happen when the interface is in promiscuous mode.
704 	 */
705 	if (((ifp->if_flags & (IFF_PROMISC | IFF_PPROMISC)) == IFF_PROMISC) &&
706 	    (eh->ether_dhost[0] & 1) == 0 &&
707 	    bcmp(eh->ether_dhost, IFP2AC(ifp)->ac_enaddr, ETHER_ADDR_LEN)) {
708 		m_freem(m);
709 		return;
710 	}
711 
712 post_stats:
713 	if (IPFW_LOADED && ether_ipfw != 0) {
714 		if (!ether_ipfw_chk(&m, NULL, &rule, eh)) {
715 			m_freem(m);
716 			return;
717 		}
718 	}
719 
720 	ether_type = ntohs(save_eh.ether_type);
721 
722 	if (m->m_flags & M_VLANTAG) {
723 		if (ether_type == ETHERTYPE_VLAN) {
724 			/*
725 			 * To prevent possible dangerous recursion,
726 			 * we don't do vlan-in-vlan
727 			 */
728 			m->m_pkthdr.rcvif->if_noproto++;
729 			m_freem(m);
730 		}
731 
732 		if (vlan_input_p != NULL) {
733 			ether_restore_header(&m, eh, &save_eh);
734 			if (m != NULL)
735 				vlan_input_p(m, chain);
736 		} else {
737 			m->m_pkthdr.rcvif->if_noproto++;
738 			m_freem(m);
739 		}
740 		return;
741 	}
742 	KKASSERT(ether_type != ETHERTYPE_VLAN);
743 
744 	switch (ether_type) {
745 #ifdef INET
746 	case ETHERTYPE_IP:
747 		if (ipflow_fastforward(m, ifp->if_serializer))
748 			return;
749 		isr = NETISR_IP;
750 		break;
751 
752 	case ETHERTYPE_ARP:
753 		if (ifp->if_flags & IFF_NOARP) {
754 			/* Discard packet if ARP is disabled on interface */
755 			m_freem(m);
756 			return;
757 		}
758 		isr = NETISR_ARP;
759 		break;
760 #endif
761 
762 #ifdef INET6
763 	case ETHERTYPE_IPV6:
764 		isr = NETISR_IPV6;
765 		break;
766 #endif
767 
768 #ifdef IPX
769 	case ETHERTYPE_IPX:
770 		if (ef_inputp && ef_inputp(ifp, &save_eh, m) == 0)
771 			return;
772 		isr = NETISR_IPX;
773 		break;
774 #endif
775 
776 #ifdef NS
777 	case 0x8137: /* Novell Ethernet_II Ethernet TYPE II */
778 		isr = NETISR_NS;
779 		break;
780 
781 #endif
782 
783 #ifdef NETATALK
784 	case ETHERTYPE_AT:
785 		isr = NETISR_ATALK1;
786 		break;
787 	case ETHERTYPE_AARP:
788 		isr = NETISR_AARP;
789 		break;
790 #endif
791 
792 	default:
793 #ifdef IPX
794 		if (ef_inputp && ef_inputp(ifp, &save_eh, m) == 0)
795 			return;
796 #endif
797 #ifdef NS
798 		checksum = mtod(m, ushort *);
799 		/* Novell 802.3 */
800 		if ((ether_type <= ETHERMTU) &&
801 		    ((*checksum == 0xffff) || (*checksum == 0xE0E0))) {
802 			if (*checksum == 0xE0E0) {
803 				m->m_pkthdr.len -= 3;
804 				m->m_len -= 3;
805 				m->m_data += 3;
806 			}
807 			isr = NETISR_NS;
808 			break;
809 		}
810 #endif
811 #ifdef NETATALK
812 		if (ether_type > ETHERMTU)
813 			goto dropanyway;
814 		l = mtod(m, struct llc *);
815 		if (l->llc_dsap == LLC_SNAP_LSAP &&
816 		    l->llc_ssap == LLC_SNAP_LSAP &&
817 		    l->llc_control == LLC_UI) {
818 			if (bcmp(&(l->llc_snap_org_code)[0], at_org_code,
819 				 sizeof at_org_code) == 0 &&
820 			    ntohs(l->llc_snap_ether_type) == ETHERTYPE_AT) {
821 				m_adj(m, sizeof(struct llc));
822 				isr = NETISR_ATALK2;
823 				break;
824 			}
825 			if (bcmp(&(l->llc_snap_org_code)[0], aarp_org_code,
826 				 sizeof aarp_org_code) == 0 &&
827 			    ntohs(l->llc_snap_ether_type) == ETHERTYPE_AARP) {
828 				m_adj(m, sizeof(struct llc));
829 				isr = NETISR_AARP;
830 				break;
831 			}
832 		}
833 dropanyway:
834 #endif
835 		if (ng_ether_input_orphan_p != NULL)
836 			(*ng_ether_input_orphan_p)(ifp, m, &save_eh);
837 		else
838 			m_freem(m);
839 		return;
840 	}
841 
842 #ifdef ETHER_INPUT_CHAIN
843 	if (chain != NULL) {
844 		struct mbuf_chain *c;
845 		lwkt_port_t port;
846 		int cpuid;
847 
848 		port = netisr_mport(isr, &m);
849 		if (port == NULL)
850 			return;
851 
852 		m->m_pkthdr.header = port; /* XXX */
853 		cpuid = port->mpu_td->td_gd->gd_cpuid;
854 
855 		c = &chain[cpuid];
856 		if (c->mc_head == NULL) {
857 			c->mc_head = c->mc_tail = m;
858 		} else {
859 			c->mc_tail->m_nextpkt = m;
860 			c->mc_tail = m;
861 		}
862 		m->m_nextpkt = NULL;
863 	} else
864 #endif	/* ETHER_INPUT_CHAIN */
865 		netisr_dispatch(isr, m);
866 }
867 
868 void
869 ether_demux(struct ifnet *ifp, struct mbuf *m)
870 {
871 	ether_demux_chain(ifp, m, NULL);
872 }
873 
874 /*
875  * Perform common duties while attaching to interface list
876  */
877 
878 void
879 ether_ifattach(struct ifnet *ifp, uint8_t *lla, lwkt_serialize_t serializer)
880 {
881 	ether_ifattach_bpf(ifp, lla, DLT_EN10MB, sizeof(struct ether_header),
882 			   serializer);
883 }
884 
885 void
886 ether_ifattach_bpf(struct ifnet *ifp, uint8_t *lla, u_int dlt, u_int hdrlen,
887 		   lwkt_serialize_t serializer)
888 {
889 	struct sockaddr_dl *sdl;
890 
891 	ifp->if_type = IFT_ETHER;
892 	ifp->if_addrlen = ETHER_ADDR_LEN;
893 	ifp->if_hdrlen = ETHER_HDR_LEN;
894 	if_attach(ifp, serializer);
895 	ifp->if_mtu = ETHERMTU;
896 	if (ifp->if_baudrate == 0)
897 		ifp->if_baudrate = 10000000;
898 	ifp->if_output = ether_output;
899 	ifp->if_input = ether_input;
900 	ifp->if_resolvemulti = ether_resolvemulti;
901 	ifp->if_broadcastaddr = etherbroadcastaddr;
902 	sdl = IF_LLSOCKADDR(ifp);
903 	sdl->sdl_type = IFT_ETHER;
904 	sdl->sdl_alen = ifp->if_addrlen;
905 	bcopy(lla, LLADDR(sdl), ifp->if_addrlen);
906 	/*
907 	 * XXX Keep the current drivers happy.
908 	 * XXX Remove once all drivers have been cleaned up
909 	 */
910 	if (lla != IFP2AC(ifp)->ac_enaddr)
911 		bcopy(lla, IFP2AC(ifp)->ac_enaddr, ifp->if_addrlen);
912 	bpfattach(ifp, dlt, hdrlen);
913 	if (ng_ether_attach_p != NULL)
914 		(*ng_ether_attach_p)(ifp);
915 
916 	if_printf(ifp, "MAC address: %6D\n", lla, ":");
917 }
918 
919 /*
920  * Perform common duties while detaching an Ethernet interface
921  */
922 void
923 ether_ifdetach(struct ifnet *ifp)
924 {
925 	if_down(ifp);
926 
927 	if (ng_ether_detach_p != NULL)
928 		(*ng_ether_detach_p)(ifp);
929 	bpfdetach(ifp);
930 	if_detach(ifp);
931 }
932 
933 int
934 ether_ioctl(struct ifnet *ifp, int command, caddr_t data)
935 {
936 	struct ifaddr *ifa = (struct ifaddr *) data;
937 	struct ifreq *ifr = (struct ifreq *) data;
938 	int error = 0;
939 
940 #define IF_INIT(ifp) \
941 do { \
942 	if (((ifp)->if_flags & IFF_UP) == 0) { \
943 		(ifp)->if_flags |= IFF_UP; \
944 		(ifp)->if_init((ifp)->if_softc); \
945 	} \
946 } while (0)
947 
948 	ASSERT_SERIALIZED(ifp->if_serializer);
949 
950 	switch (command) {
951 	case SIOCSIFADDR:
952 		switch (ifa->ifa_addr->sa_family) {
953 #ifdef INET
954 		case AF_INET:
955 			IF_INIT(ifp);	/* before arpwhohas */
956 			arp_ifinit(ifp, ifa);
957 			break;
958 #endif
959 #ifdef IPX
960 		/*
961 		 * XXX - This code is probably wrong
962 		 */
963 		case AF_IPX:
964 			{
965 			struct ipx_addr *ina = &IA_SIPX(ifa)->sipx_addr;
966 			struct arpcom *ac = IFP2AC(ifp);
967 
968 			if (ipx_nullhost(*ina))
969 				ina->x_host = *(union ipx_host *) ac->ac_enaddr;
970 			else
971 				bcopy(ina->x_host.c_host, ac->ac_enaddr,
972 				      sizeof ac->ac_enaddr);
973 
974 			IF_INIT(ifp);	/* Set new address. */
975 			break;
976 			}
977 #endif
978 #ifdef NS
979 		/*
980 		 * XXX - This code is probably wrong
981 		 */
982 		case AF_NS:
983 		{
984 			struct ns_addr *ina = &(IA_SNS(ifa)->sns_addr);
985 			struct arpcom *ac = IFP2AC(ifp);
986 
987 			if (ns_nullhost(*ina))
988 				ina->x_host = *(union ns_host *)(ac->ac_enaddr);
989 			else
990 				bcopy(ina->x_host.c_host, ac->ac_enaddr,
991 				      sizeof ac->ac_enaddr);
992 
993 			/*
994 			 * Set new address
995 			 */
996 			IF_INIT(ifp);
997 			break;
998 		}
999 #endif
1000 		default:
1001 			IF_INIT(ifp);
1002 			break;
1003 		}
1004 		break;
1005 
1006 	case SIOCGIFADDR:
1007 		bcopy(IFP2AC(ifp)->ac_enaddr,
1008 		      ((struct sockaddr *)ifr->ifr_data)->sa_data,
1009 		      ETHER_ADDR_LEN);
1010 		break;
1011 
1012 	case SIOCSIFMTU:
1013 		/*
1014 		 * Set the interface MTU.
1015 		 */
1016 		if (ifr->ifr_mtu > ETHERMTU) {
1017 			error = EINVAL;
1018 		} else {
1019 			ifp->if_mtu = ifr->ifr_mtu;
1020 		}
1021 		break;
1022 	default:
1023 		error = EINVAL;
1024 		break;
1025 	}
1026 	return (error);
1027 
1028 #undef IF_INIT
1029 }
1030 
1031 int
1032 ether_resolvemulti(
1033 	struct ifnet *ifp,
1034 	struct sockaddr **llsa,
1035 	struct sockaddr *sa)
1036 {
1037 	struct sockaddr_dl *sdl;
1038 	struct sockaddr_in *sin;
1039 #ifdef INET6
1040 	struct sockaddr_in6 *sin6;
1041 #endif
1042 	u_char *e_addr;
1043 
1044 	switch(sa->sa_family) {
1045 	case AF_LINK:
1046 		/*
1047 		 * No mapping needed. Just check that it's a valid MC address.
1048 		 */
1049 		sdl = (struct sockaddr_dl *)sa;
1050 		e_addr = LLADDR(sdl);
1051 		if ((e_addr[0] & 1) != 1)
1052 			return EADDRNOTAVAIL;
1053 		*llsa = 0;
1054 		return 0;
1055 
1056 #ifdef INET
1057 	case AF_INET:
1058 		sin = (struct sockaddr_in *)sa;
1059 		if (!IN_MULTICAST(ntohl(sin->sin_addr.s_addr)))
1060 			return EADDRNOTAVAIL;
1061 		MALLOC(sdl, struct sockaddr_dl *, sizeof *sdl, M_IFMADDR,
1062 		       M_WAITOK | M_ZERO);
1063 		sdl->sdl_len = sizeof *sdl;
1064 		sdl->sdl_family = AF_LINK;
1065 		sdl->sdl_index = ifp->if_index;
1066 		sdl->sdl_type = IFT_ETHER;
1067 		sdl->sdl_alen = ETHER_ADDR_LEN;
1068 		e_addr = LLADDR(sdl);
1069 		ETHER_MAP_IP_MULTICAST(&sin->sin_addr, e_addr);
1070 		*llsa = (struct sockaddr *)sdl;
1071 		return 0;
1072 #endif
1073 #ifdef INET6
1074 	case AF_INET6:
1075 		sin6 = (struct sockaddr_in6 *)sa;
1076 		if (IN6_IS_ADDR_UNSPECIFIED(&sin6->sin6_addr)) {
1077 			/*
1078 			 * An IP6 address of 0 means listen to all
1079 			 * of the Ethernet multicast address used for IP6.
1080 			 * (This is used for multicast routers.)
1081 			 */
1082 			ifp->if_flags |= IFF_ALLMULTI;
1083 			*llsa = 0;
1084 			return 0;
1085 		}
1086 		if (!IN6_IS_ADDR_MULTICAST(&sin6->sin6_addr))
1087 			return EADDRNOTAVAIL;
1088 		MALLOC(sdl, struct sockaddr_dl *, sizeof *sdl, M_IFMADDR,
1089 		       M_WAITOK | M_ZERO);
1090 		sdl->sdl_len = sizeof *sdl;
1091 		sdl->sdl_family = AF_LINK;
1092 		sdl->sdl_index = ifp->if_index;
1093 		sdl->sdl_type = IFT_ETHER;
1094 		sdl->sdl_alen = ETHER_ADDR_LEN;
1095 		e_addr = LLADDR(sdl);
1096 		ETHER_MAP_IPV6_MULTICAST(&sin6->sin6_addr, e_addr);
1097 		*llsa = (struct sockaddr *)sdl;
1098 		return 0;
1099 #endif
1100 
1101 	default:
1102 		/*
1103 		 * Well, the text isn't quite right, but it's the name
1104 		 * that counts...
1105 		 */
1106 		return EAFNOSUPPORT;
1107 	}
1108 }
1109 
1110 #if 0
1111 /*
1112  * This is for reference.  We have a table-driven version
1113  * of the little-endian crc32 generator, which is faster
1114  * than the double-loop.
1115  */
1116 uint32_t
1117 ether_crc32_le(const uint8_t *buf, size_t len)
1118 {
1119 	uint32_t c, crc, carry;
1120 	size_t i, j;
1121 
1122 	crc = 0xffffffffU;	/* initial value */
1123 
1124 	for (i = 0; i < len; i++) {
1125 		c = buf[i];
1126 		for (j = 0; j < 8; j++) {
1127 			carry = ((crc & 0x01) ? 1 : 0) ^ (c & 0x01);
1128 			crc >>= 1;
1129 			c >>= 1;
1130 			if (carry)
1131 				crc = (crc ^ ETHER_CRC_POLY_LE);
1132 		}
1133 	}
1134 
1135 	return (crc);
1136 }
1137 #else
1138 uint32_t
1139 ether_crc32_le(const uint8_t *buf, size_t len)
1140 {
1141 	static const uint32_t crctab[] = {
1142 		0x00000000, 0x1db71064, 0x3b6e20c8, 0x26d930ac,
1143 		0x76dc4190, 0x6b6b51f4, 0x4db26158, 0x5005713c,
1144 		0xedb88320, 0xf00f9344, 0xd6d6a3e8, 0xcb61b38c,
1145 		0x9b64c2b0, 0x86d3d2d4, 0xa00ae278, 0xbdbdf21c
1146 	};
1147 	uint32_t crc;
1148 	size_t i;
1149 
1150 	crc = 0xffffffffU;	/* initial value */
1151 
1152 	for (i = 0; i < len; i++) {
1153 		crc ^= buf[i];
1154 		crc = (crc >> 4) ^ crctab[crc & 0xf];
1155 		crc = (crc >> 4) ^ crctab[crc & 0xf];
1156 	}
1157 
1158 	return (crc);
1159 }
1160 #endif
1161 
1162 uint32_t
1163 ether_crc32_be(const uint8_t *buf, size_t len)
1164 {
1165 	uint32_t c, crc, carry;
1166 	size_t i, j;
1167 
1168 	crc = 0xffffffffU;	/* initial value */
1169 
1170 	for (i = 0; i < len; i++) {
1171 		c = buf[i];
1172 		for (j = 0; j < 8; j++) {
1173 			carry = ((crc & 0x80000000U) ? 1 : 0) ^ (c & 0x01);
1174 			crc <<= 1;
1175 			c >>= 1;
1176 			if (carry)
1177 				crc = (crc ^ ETHER_CRC_POLY_BE) | carry;
1178 		}
1179 	}
1180 
1181 	return (crc);
1182 }
1183 
1184 /*
1185  * find the size of ethernet header, and call classifier
1186  */
1187 void
1188 altq_etherclassify(struct ifaltq *ifq, struct mbuf *m,
1189 		   struct altq_pktattr *pktattr)
1190 {
1191 	struct ether_header *eh;
1192 	uint16_t ether_type;
1193 	int hlen, af, hdrsize;
1194 	caddr_t hdr;
1195 
1196 	hlen = sizeof(struct ether_header);
1197 	eh = mtod(m, struct ether_header *);
1198 
1199 	ether_type = ntohs(eh->ether_type);
1200 	if (ether_type < ETHERMTU) {
1201 		/* ick! LLC/SNAP */
1202 		struct llc *llc = (struct llc *)(eh + 1);
1203 		hlen += 8;
1204 
1205 		if (m->m_len < hlen ||
1206 		    llc->llc_dsap != LLC_SNAP_LSAP ||
1207 		    llc->llc_ssap != LLC_SNAP_LSAP ||
1208 		    llc->llc_control != LLC_UI)
1209 			goto bad;  /* not snap! */
1210 
1211 		ether_type = ntohs(llc->llc_un.type_snap.ether_type);
1212 	}
1213 
1214 	if (ether_type == ETHERTYPE_IP) {
1215 		af = AF_INET;
1216 		hdrsize = 20;  /* sizeof(struct ip) */
1217 #ifdef INET6
1218 	} else if (ether_type == ETHERTYPE_IPV6) {
1219 		af = AF_INET6;
1220 		hdrsize = 40;  /* sizeof(struct ip6_hdr) */
1221 #endif
1222 	} else
1223 		goto bad;
1224 
1225 	while (m->m_len <= hlen) {
1226 		hlen -= m->m_len;
1227 		m = m->m_next;
1228 	}
1229 	hdr = m->m_data + hlen;
1230 	if (m->m_len < hlen + hdrsize) {
1231 		/*
1232 		 * ip header is not in a single mbuf.  this should not
1233 		 * happen in the current code.
1234 		 * (todo: use m_pulldown in the future)
1235 		 */
1236 		goto bad;
1237 	}
1238 	m->m_data += hlen;
1239 	m->m_len -= hlen;
1240 	ifq_classify(ifq, m, af, pktattr);
1241 	m->m_data -= hlen;
1242 	m->m_len += hlen;
1243 
1244 	return;
1245 
1246 bad:
1247 	pktattr->pattr_class = NULL;
1248 	pktattr->pattr_hdr = NULL;
1249 	pktattr->pattr_af = AF_UNSPEC;
1250 }
1251 
1252 static void
1253 ether_restore_header(struct mbuf **m0, const struct ether_header *eh,
1254 		     const struct ether_header *save_eh)
1255 {
1256 	struct mbuf *m = *m0;
1257 
1258 	ether_restore_hdr++;
1259 
1260 	/*
1261 	 * Prepend the header, optimize for the common case of
1262 	 * eh pointing into the mbuf.
1263 	 */
1264 	if ((const void *)(eh + 1) == (void *)m->m_data) {
1265 		m->m_data -= ETHER_HDR_LEN;
1266 		m->m_len += ETHER_HDR_LEN;
1267 		m->m_pkthdr.len += ETHER_HDR_LEN;
1268 	} else {
1269 		ether_prepend_hdr++;
1270 
1271 		M_PREPEND(m, ETHER_HDR_LEN, MB_DONTWAIT);
1272 		if (m != NULL) {
1273 			bcopy(save_eh, mtod(m, struct ether_header *),
1274 			      ETHER_HDR_LEN);
1275 		}
1276 	}
1277 	*m0 = m;
1278 }
1279 
1280 #ifdef ETHER_INPUT_CHAIN
1281 
1282 static void
1283 ether_input_ipifunc(void *arg)
1284 {
1285 	struct mbuf *m, *next;
1286 	lwkt_port_t port;
1287 
1288 	m = arg;
1289 	do {
1290 		next = m->m_nextpkt;
1291 		m->m_nextpkt = NULL;
1292 
1293 		port = m->m_pkthdr.header;
1294 		m->m_pkthdr.header = NULL;
1295 
1296 		lwkt_sendmsg(port,
1297 		&m->m_hdr.mh_netmsg.nm_netmsg.nm_lmsg);
1298 
1299 		m = next;
1300 	} while (m != NULL);
1301 }
1302 
1303 void
1304 ether_input_dispatch(struct mbuf_chain *chain)
1305 {
1306 #ifdef SMP
1307 	int i;
1308 
1309 	for (i = 0; i < ncpus; ++i) {
1310 		if (chain[i].mc_head != NULL) {
1311 			lwkt_send_ipiq(globaldata_find(i),
1312 			ether_input_ipifunc, chain[i].mc_head);
1313 		}
1314 	}
1315 #else
1316 	ether_input_ipifunc(chain->mc_head);
1317 #endif
1318 }
1319 
1320 #endif	/* ETHER_INPUT_CHAIN */
1321