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      1 /*	$NetBSD: if_ethersubr.c,v 1.330 2025/04/23 12:17:05 joe 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 1.330 2025/04/23 12:17:05 joe Exp $");
     65 
     66 #ifdef _KERNEL_OPT
     67 #include "opt_inet.h"
     68 #include "opt_atalk.h"
     69 #include "opt_mbuftrace.h"
     70 #include "opt_mpls.h"
     71 #include "opt_gateway.h"
     72 #include "opt_pppoe.h"
     73 #include "opt_net_mpsafe.h"
     74 #endif
     75 
     76 #include "vlan.h"
     77 #include "pppoe.h"
     78 #include "bridge.h"
     79 #include "arp.h"
     80 #include "agr.h"
     81 
     82 #include <sys/sysctl.h>
     83 #include <sys/mbuf.h>
     84 #include <sys/mutex.h>
     85 #include <sys/ioctl.h>
     86 #include <sys/errno.h>
     87 #include <sys/device.h>
     88 #include <sys/entropy.h>
     89 #include <sys/rndsource.h>
     90 #include <sys/cpu.h>
     91 #include <sys/kmem.h>
     92 #include <sys/hook.h>
     93 
     94 #include <net/if.h>
     95 #include <net/route.h>
     96 #include <net/if_llc.h>
     97 #include <net/if_dl.h>
     98 #include <net/if_types.h>
     99 #include <net/pktqueue.h>
    100 
    101 #include <net/if_media.h>
    102 #include <dev/mii/mii.h>
    103 #include <dev/mii/miivar.h>
    104 
    105 #if NARP == 0
    106 /*
    107  * XXX there should really be a way to issue this warning from within config(8)
    108  */
    109 #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.
    110 #endif
    111 
    112 #include <net/bpf.h>
    113 
    114 #include <net/if_ether.h>
    115 #include <net/if_vlanvar.h>
    116 
    117 #if NPPPOE > 0
    118 #include <net/if_pppoe.h>
    119 #endif
    120 
    121 #if NAGR > 0
    122 #include <net/ether_slowprotocols.h>
    123 #include <net/agr/ieee8023ad.h>
    124 #include <net/agr/if_agrvar.h>
    125 #endif
    126 
    127 #if NBRIDGE > 0
    128 #include <net/if_bridgevar.h>
    129 #endif
    130 
    131 #include <netinet/in.h>
    132 #ifdef INET
    133 #include <netinet/in_var.h>
    134 #endif
    135 #include <netinet/if_inarp.h>
    136 
    137 #ifdef INET6
    138 #ifndef INET
    139 #include <netinet/in.h>
    140 #endif
    141 #include <netinet6/in6_var.h>
    142 #include <netinet6/nd6.h>
    143 #endif
    144 
    145 #include "carp.h"
    146 #if NCARP > 0
    147 #include <netinet/ip_carp.h>
    148 #endif
    149 
    150 #ifdef NETATALK
    151 #include <netatalk/at.h>
    152 #include <netatalk/at_var.h>
    153 #include <netatalk/at_extern.h>
    154 
    155 #define llc_snap_org_code llc_un.type_snap.org_code
    156 #define llc_snap_ether_type llc_un.type_snap.ether_type
    157 
    158 extern u_char	at_org_code[3];
    159 extern u_char	aarp_org_code[3];
    160 #endif /* NETATALK */
    161 
    162 #ifdef MPLS
    163 #include <netmpls/mpls.h>
    164 #include <netmpls/mpls_var.h>
    165 #endif
    166 
    167 CTASSERT(sizeof(struct ether_addr) == 6);
    168 CTASSERT(sizeof(struct ether_header) == 14);
    169 
    170 #ifdef DIAGNOSTIC
    171 static struct timeval bigpktppslim_last;
    172 static int bigpktppslim = 2;	/* XXX */
    173 static int bigpktpps_count;
    174 static kmutex_t bigpktpps_lock __cacheline_aligned;
    175 #endif
    176 
    177 const uint8_t etherbroadcastaddr[ETHER_ADDR_LEN] =
    178     { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff };
    179 const uint8_t ethermulticastaddr_slowprotocols[ETHER_ADDR_LEN] =
    180     { 0x01, 0x80, 0xc2, 0x00, 0x00, 0x02 };
    181 #define senderr(e) { error = (e); goto bad;}
    182 
    183 static pktq_rps_hash_func_t ether_pktq_rps_hash_p;
    184 
    185 static int ether_output(struct ifnet *, struct mbuf *,
    186     const struct sockaddr *, const struct rtentry *);
    187 
    188 /*
    189  * Ethernet output routine.
    190  * Encapsulate a packet of type family for the local net.
    191  * Assumes that ifp is actually pointer to ethercom structure.
    192  */
    193 static int
    194 ether_output(struct ifnet * const ifp0, struct mbuf * const m0,
    195     const struct sockaddr * const dst, const struct rtentry *rt)
    196 {
    197 	uint8_t esrc[ETHER_ADDR_LEN], edst[ETHER_ADDR_LEN];
    198 	uint16_t etype = 0;
    199 	int error = 0, hdrcmplt = 0;
    200 	struct mbuf *m = m0;
    201 	struct mbuf *mcopy = NULL;
    202 	struct ether_header *eh;
    203 	struct ifnet *ifp = ifp0;
    204 #ifdef INET
    205 	struct arphdr *ah;
    206 #endif
    207 #ifdef NETATALK
    208 	struct at_ifaddr *aa;
    209 #endif
    210 
    211 #ifdef MBUFTRACE
    212 	m_claimm(m, ifp->if_mowner);
    213 #endif
    214 
    215 #if NCARP > 0
    216 	if (ifp->if_type == IFT_CARP) {
    217 		struct ifaddr *ifa;
    218 		int s = pserialize_read_enter();
    219 
    220 		/* loop back if this is going to the carp interface */
    221 		if (dst != NULL && ifp0->if_link_state == LINK_STATE_UP &&
    222 		    (ifa = ifa_ifwithaddr(dst)) != NULL) {
    223 			if (ifa->ifa_ifp == ifp0) {
    224 				pserialize_read_exit(s);
    225 				return looutput(ifp0, m, dst, rt);
    226 			}
    227 		}
    228 		pserialize_read_exit(s);
    229 
    230 		ifp = ifp->if_carpdev;
    231 		/* ac = (struct arpcom *)ifp; */
    232 
    233 		if ((ifp0->if_flags & (IFF_UP | IFF_RUNNING)) !=
    234 		    (IFF_UP | IFF_RUNNING))
    235 			senderr(ENETDOWN);
    236 	}
    237 #endif
    238 
    239 	if ((ifp->if_flags & (IFF_UP | IFF_RUNNING)) != (IFF_UP | IFF_RUNNING))
    240 		senderr(ENETDOWN);
    241 
    242 	switch (dst->sa_family) {
    243 
    244 #ifdef INET
    245 	case AF_INET:
    246 		if (m->m_flags & M_BCAST) {
    247 			memcpy(edst, etherbroadcastaddr, sizeof(edst));
    248 		} else if (m->m_flags & M_MCAST) {
    249 			ETHER_MAP_IP_MULTICAST(&satocsin(dst)->sin_addr, edst);
    250 		} else {
    251 			error = arpresolve(ifp0, rt, m, dst, edst, sizeof(edst));
    252 			if (error)
    253 				return (error == EWOULDBLOCK) ? 0 : error;
    254 		}
    255 		/* If broadcasting on a simplex interface, loopback a copy */
    256 		if ((m->m_flags & M_BCAST) && (ifp->if_flags & IFF_SIMPLEX))
    257 			mcopy = m_copypacket(m, M_DONTWAIT);
    258 		etype = htons(ETHERTYPE_IP);
    259 		break;
    260 
    261 	case AF_ARP:
    262 		ah = mtod(m, struct arphdr *);
    263 		if (m->m_flags & M_BCAST) {
    264 			memcpy(edst, etherbroadcastaddr, sizeof(edst));
    265 		} else {
    266 			void *tha = ar_tha(ah);
    267 
    268 			if (tha == NULL) {
    269 				/* fake with ARPHRD_IEEE1394 */
    270 				m_freem(m);
    271 				return 0;
    272 			}
    273 			memcpy(edst, tha, sizeof(edst));
    274 		}
    275 
    276 		ah->ar_hrd = htons(ARPHRD_ETHER);
    277 
    278 		switch (ntohs(ah->ar_op)) {
    279 		case ARPOP_REVREQUEST:
    280 		case ARPOP_REVREPLY:
    281 			etype = htons(ETHERTYPE_REVARP);
    282 			break;
    283 
    284 		case ARPOP_REQUEST:
    285 		case ARPOP_REPLY:
    286 		default:
    287 			etype = htons(ETHERTYPE_ARP);
    288 		}
    289 		break;
    290 #endif
    291 
    292 #ifdef INET6
    293 	case AF_INET6:
    294 		if (m->m_flags & M_BCAST) {
    295 			memcpy(edst, etherbroadcastaddr, sizeof(edst));
    296 		} else if (m->m_flags & M_MCAST) {
    297 			ETHER_MAP_IPV6_MULTICAST(&satocsin6(dst)->sin6_addr,
    298 			    edst);
    299 		} else {
    300 			error = nd6_resolve(ifp0, rt, m, dst, edst,
    301 			    sizeof(edst));
    302 			if (error)
    303 				return (error == EWOULDBLOCK) ? 0 : error;
    304 		}
    305 		etype = htons(ETHERTYPE_IPV6);
    306 		break;
    307 #endif
    308 
    309 #ifdef NETATALK
    310 	case AF_APPLETALK: {
    311 		struct ifaddr *ifa;
    312 		int s;
    313 
    314 		KERNEL_LOCK(1, NULL);
    315 
    316 		if (!aarpresolve(ifp, m, (const struct sockaddr_at *)dst, edst)) {
    317 			KERNEL_UNLOCK_ONE(NULL);
    318 			return 0;
    319 		}
    320 
    321 		/*
    322 		 * ifaddr is the first thing in at_ifaddr
    323 		 */
    324 		s = pserialize_read_enter();
    325 		ifa = at_ifawithnet((const struct sockaddr_at *)dst, ifp);
    326 		if (ifa == NULL) {
    327 			pserialize_read_exit(s);
    328 			KERNEL_UNLOCK_ONE(NULL);
    329 			senderr(EADDRNOTAVAIL);
    330 		}
    331 		aa = (struct at_ifaddr *)ifa;
    332 
    333 		/*
    334 		 * In the phase 2 case, we need to prepend an mbuf for the
    335 		 * llc header.
    336 		 */
    337 		if (aa->aa_flags & AFA_PHASE2) {
    338 			struct llc llc;
    339 
    340 			M_PREPEND(m, sizeof(struct llc), M_DONTWAIT);
    341 			if (m == NULL) {
    342 				pserialize_read_exit(s);
    343 				KERNEL_UNLOCK_ONE(NULL);
    344 				senderr(ENOBUFS);
    345 			}
    346 
    347 			llc.llc_dsap = llc.llc_ssap = LLC_SNAP_LSAP;
    348 			llc.llc_control = LLC_UI;
    349 			memcpy(llc.llc_snap_org_code, at_org_code,
    350 			    sizeof(llc.llc_snap_org_code));
    351 			llc.llc_snap_ether_type = htons(ETHERTYPE_ATALK);
    352 			memcpy(mtod(m, void *), &llc, sizeof(struct llc));
    353 		} else {
    354 			etype = htons(ETHERTYPE_ATALK);
    355 		}
    356 		pserialize_read_exit(s);
    357 		KERNEL_UNLOCK_ONE(NULL);
    358 		break;
    359 	}
    360 #endif /* NETATALK */
    361 
    362 	case pseudo_AF_HDRCMPLT:
    363 		hdrcmplt = 1;
    364 		memcpy(esrc,
    365 		    ((const struct ether_header *)dst->sa_data)->ether_shost,
    366 		    sizeof(esrc));
    367 		/* FALLTHROUGH */
    368 
    369 	case AF_UNSPEC:
    370 		memcpy(edst,
    371 		    ((const struct ether_header *)dst->sa_data)->ether_dhost,
    372 		    sizeof(edst));
    373 		/* AF_UNSPEC doesn't swap the byte order of the ether_type. */
    374 		etype = ((const struct ether_header *)dst->sa_data)->ether_type;
    375 		break;
    376 
    377 	default:
    378 		printf("%s: can't handle af%d\n", ifp->if_xname,
    379 		    dst->sa_family);
    380 		senderr(EAFNOSUPPORT);
    381 	}
    382 
    383 #ifdef MPLS
    384 	{
    385 		struct m_tag *mtag;
    386 		mtag = m_tag_find(m, PACKET_TAG_MPLS);
    387 		if (mtag != NULL) {
    388 			/* Having the tag itself indicates it's MPLS */
    389 			etype = htons(ETHERTYPE_MPLS);
    390 			m_tag_delete(m, mtag);
    391 		}
    392 	}
    393 #endif
    394 
    395 	if (mcopy)
    396 		(void)looutput(ifp, mcopy, dst, rt);
    397 
    398 	KASSERT((m->m_flags & M_PKTHDR) != 0);
    399 
    400 	/*
    401 	 * If no ether type is set, this must be a 802.2 formatted packet.
    402 	 */
    403 	if (etype == 0)
    404 		etype = htons(m->m_pkthdr.len);
    405 
    406 	/*
    407 	 * Add local net header. If no space in first mbuf, allocate another.
    408 	 */
    409 	M_PREPEND(m, sizeof(struct ether_header), M_DONTWAIT);
    410 	if (m == NULL)
    411 		senderr(ENOBUFS);
    412 
    413 	eh = mtod(m, struct ether_header *);
    414 	/* Note: etype is already in network byte order. */
    415 	memcpy(&eh->ether_type, &etype, sizeof(eh->ether_type));
    416 	memcpy(eh->ether_dhost, edst, sizeof(edst));
    417 	if (hdrcmplt) {
    418 		memcpy(eh->ether_shost, esrc, sizeof(eh->ether_shost));
    419 	} else {
    420 	 	memcpy(eh->ether_shost, CLLADDR(ifp->if_sadl),
    421 		    sizeof(eh->ether_shost));
    422 	}
    423 
    424 #if NCARP > 0
    425 	if (ifp0 != ifp && ifp0->if_type == IFT_CARP) {
    426 		/* update with virtual MAC */
    427 		memcpy(eh->ether_shost, CLLADDR(ifp0->if_sadl),
    428 		    sizeof(eh->ether_shost));
    429 	}
    430 #endif
    431 
    432 	if ((error = pfil_run_hooks(ifp->if_pfil, &m, ifp, PFIL_OUT)) != 0)
    433 		return error;
    434 	if (m == NULL)
    435 		return 0;
    436 
    437 #if NBRIDGE > 0
    438 	/*
    439 	 * Bridges require special output handling.
    440 	 */
    441 	if (ifp->if_bridge)
    442 		return bridge_output(ifp, m, NULL, NULL);
    443 #endif
    444 
    445 #if NCARP > 0
    446 	if (ifp != ifp0)
    447 		if_statadd(ifp0, if_obytes, m->m_pkthdr.len + ETHER_HDR_LEN);
    448 #endif
    449 
    450 #ifdef ALTQ
    451 	KERNEL_LOCK(1, NULL);
    452 	/*
    453 	 * If ALTQ is enabled on the parent interface, do
    454 	 * classification; the queueing discipline might not
    455 	 * require classification, but might require the
    456 	 * address family/header pointer in the pktattr.
    457 	 */
    458 	if (ALTQ_IS_ENABLED(&ifp->if_snd))
    459 		altq_etherclassify(&ifp->if_snd, m);
    460 	KERNEL_UNLOCK_ONE(NULL);
    461 #endif
    462 	return ifq_enqueue(ifp, m);
    463 
    464 bad:
    465 	if_statinc(ifp, if_oerrors);
    466 	m_freem(m);
    467 	return error;
    468 }
    469 
    470 #ifdef ALTQ
    471 /*
    472  * This routine is a slight hack to allow a packet to be classified
    473  * if the Ethernet headers are present.  It will go away when ALTQ's
    474  * classification engine understands link headers.
    475  *
    476  * XXX: We may need to do m_pullups here. First to ensure struct ether_header
    477  * is indeed contiguous, then to read the LLC and so on.
    478  */
    479 void
    480 altq_etherclassify(struct ifaltq *ifq, struct mbuf *m)
    481 {
    482 	struct ether_header *eh;
    483 	struct mbuf *mtop = m;
    484 	uint16_t ether_type;
    485 	int hlen, af, hdrsize;
    486 	void *hdr;
    487 
    488 	KASSERT((mtop->m_flags & M_PKTHDR) != 0);
    489 
    490 	hlen = ETHER_HDR_LEN;
    491 	eh = mtod(m, struct ether_header *);
    492 
    493 	ether_type = htons(eh->ether_type);
    494 
    495 	if (ether_type < ETHERMTU) {
    496 		/* LLC/SNAP */
    497 		struct llc *llc = (struct llc *)(eh + 1);
    498 		hlen += 8;
    499 
    500 		if (m->m_len < hlen ||
    501 		    llc->llc_dsap != LLC_SNAP_LSAP ||
    502 		    llc->llc_ssap != LLC_SNAP_LSAP ||
    503 		    llc->llc_control != LLC_UI) {
    504 			/* Not SNAP. */
    505 			goto bad;
    506 		}
    507 
    508 		ether_type = htons(llc->llc_un.type_snap.ether_type);
    509 	}
    510 
    511 	switch (ether_type) {
    512 	case ETHERTYPE_IP:
    513 		af = AF_INET;
    514 		hdrsize = 20;		/* sizeof(struct ip) */
    515 		break;
    516 
    517 	case ETHERTYPE_IPV6:
    518 		af = AF_INET6;
    519 		hdrsize = 40;		/* sizeof(struct ip6_hdr) */
    520 		break;
    521 
    522 	default:
    523 		af = AF_UNSPEC;
    524 		hdrsize = 0;
    525 		break;
    526 	}
    527 
    528 	while (m->m_len <= hlen) {
    529 		hlen -= m->m_len;
    530 		m = m->m_next;
    531 		if (m == NULL)
    532 			goto bad;
    533 	}
    534 
    535 	if (m->m_len < (hlen + hdrsize)) {
    536 		/*
    537 		 * protocol header not in a single mbuf.
    538 		 * We can't cope with this situation right
    539 		 * now (but it shouldn't ever happen, really, anyhow).
    540 		 */
    541 #ifdef DEBUG
    542 		printf("altq_etherclassify: headers span multiple mbufs: "
    543 		    "%d < %d\n", m->m_len, (hlen + hdrsize));
    544 #endif
    545 		goto bad;
    546 	}
    547 
    548 	m->m_data += hlen;
    549 	m->m_len -= hlen;
    550 
    551 	hdr = mtod(m, void *);
    552 
    553 	if (ALTQ_NEEDS_CLASSIFY(ifq)) {
    554 		mtop->m_pkthdr.pattr_class =
    555 		    (*ifq->altq_classify)(ifq->altq_clfier, m, af);
    556 	}
    557 	mtop->m_pkthdr.pattr_af = af;
    558 	mtop->m_pkthdr.pattr_hdr = hdr;
    559 
    560 	m->m_data -= hlen;
    561 	m->m_len += hlen;
    562 
    563 	return;
    564 
    565 bad:
    566 	mtop->m_pkthdr.pattr_class = NULL;
    567 	mtop->m_pkthdr.pattr_hdr = NULL;
    568 	mtop->m_pkthdr.pattr_af = AF_UNSPEC;
    569 }
    570 #endif /* ALTQ */
    571 
    572 #if defined (LLC) || defined (NETATALK)
    573 static void
    574 ether_input_llc(struct ifnet *ifp, struct mbuf *m, struct ether_header *eh)
    575 {
    576 	pktqueue_t *pktq = NULL;
    577 	struct llc *l;
    578 
    579 	if (m->m_len < sizeof(*eh) + sizeof(struct llc))
    580 		goto error;
    581 
    582 	l = (struct llc *)(eh+1);
    583 	switch (l->llc_dsap) {
    584 #ifdef NETATALK
    585 	case LLC_SNAP_LSAP:
    586 		switch (l->llc_control) {
    587 		case LLC_UI:
    588 			if (l->llc_ssap != LLC_SNAP_LSAP)
    589 				goto error;
    590 
    591 			if (memcmp(&(l->llc_snap_org_code)[0],
    592 			    at_org_code, sizeof(at_org_code)) == 0 &&
    593 			    ntohs(l->llc_snap_ether_type) ==
    594 			    ETHERTYPE_ATALK) {
    595 				pktq = at_pktq2;
    596 				m_adj(m, sizeof(struct ether_header)
    597 				    + sizeof(struct llc));
    598 				break;
    599 			}
    600 
    601 			if (memcmp(&(l->llc_snap_org_code)[0],
    602 			    aarp_org_code,
    603 			    sizeof(aarp_org_code)) == 0 &&
    604 			    ntohs(l->llc_snap_ether_type) ==
    605 			    ETHERTYPE_AARP) {
    606 				m_adj(m, sizeof(struct ether_header)
    607 				    + sizeof(struct llc));
    608 				aarpinput(ifp, m); /* XXX queue? */
    609 				return;
    610 			}
    611 
    612 		default:
    613 			goto error;
    614 		}
    615 		break;
    616 #endif
    617 	default:
    618 		goto noproto;
    619 	}
    620 
    621 	KASSERT(pktq != NULL);
    622 	if (__predict_false(!pktq_enqueue(pktq, m, 0))) {
    623 		m_freem(m);
    624 	}
    625 	return;
    626 
    627 noproto:
    628 	m_freem(m);
    629 	if_statinc(ifp, if_noproto);
    630 	return;
    631 error:
    632 	m_freem(m);
    633 	if_statinc(ifp, if_ierrors);
    634 	return;
    635 }
    636 #endif /* defined (LLC) || defined (NETATALK) */
    637 
    638 /*
    639  * Process a received Ethernet packet;
    640  * the packet is in the mbuf chain m with
    641  * the ether header.
    642  */
    643 void
    644 ether_input(struct ifnet *ifp, struct mbuf *m)
    645 {
    646 #if NVLAN > 0 || defined(MBUFTRACE)
    647 	struct ethercom *ec = (struct ethercom *) ifp;
    648 #endif
    649 	pktqueue_t *pktq = NULL;
    650 	uint16_t etype;
    651 	struct ether_header *eh;
    652 	size_t ehlen;
    653 	static int earlypkts;
    654 
    655 	/* No RPS for not-IP. */
    656 	pktq_rps_hash_func_t rps_hash = NULL;
    657 
    658 	KASSERT(!cpu_intr_p());
    659 	KASSERT((m->m_flags & M_PKTHDR) != 0);
    660 
    661 	if ((ifp->if_flags & IFF_UP) == 0)
    662 		goto drop;
    663 
    664 #ifdef MBUFTRACE
    665 	m_claimm(m, &ec->ec_rx_mowner);
    666 #endif
    667 
    668 	if (__predict_false(m->m_len < sizeof(*eh))) {
    669 		if ((m = m_pullup(m, sizeof(*eh))) == NULL) {
    670 			if_statinc(ifp, if_ierrors);
    671 			return;
    672 		}
    673 	}
    674 
    675 	eh = mtod(m, struct ether_header *);
    676 	etype = ntohs(eh->ether_type);
    677 	ehlen = sizeof(*eh);
    678 
    679 	if (__predict_false(earlypkts < 100 ||
    680 		entropy_epoch() == (unsigned)-1)) {
    681 		rnd_add_data(NULL, eh, ehlen, 0);
    682 		earlypkts++;
    683 	}
    684 
    685 	/*
    686 	 * Determine if the packet is within its size limits. For MPLS the
    687 	 * header length is variable, so we skip the check.
    688 	 */
    689 	if (etype != ETHERTYPE_MPLS && m->m_pkthdr.len >
    690 	    ETHER_MAX_FRAME(ifp, etype, m->m_flags & M_HASFCS)) {
    691 #ifdef DIAGNOSTIC
    692 		mutex_enter(&bigpktpps_lock);
    693 		if (ppsratecheck(&bigpktppslim_last, &bigpktpps_count,
    694 		    bigpktppslim)) {
    695 			printf("%s: discarding oversize frame (len=%d)\n",
    696 			    ifp->if_xname, m->m_pkthdr.len);
    697 		}
    698 		mutex_exit(&bigpktpps_lock);
    699 #endif
    700 		goto error;
    701 	}
    702 
    703 	if (ETHER_IS_MULTICAST(eh->ether_dhost)) {
    704 		/*
    705 		 * If this is not a simplex interface, drop the packet
    706 		 * if it came from us.
    707 		 */
    708 		if ((ifp->if_flags & IFF_SIMPLEX) == 0 &&
    709 		    memcmp(CLLADDR(ifp->if_sadl), eh->ether_shost,
    710 		    ETHER_ADDR_LEN) == 0) {
    711 			goto drop;
    712 		}
    713 
    714 		if (memcmp(etherbroadcastaddr,
    715 		    eh->ether_dhost, ETHER_ADDR_LEN) == 0)
    716 			m->m_flags |= M_BCAST;
    717 		else
    718 			m->m_flags |= M_MCAST;
    719 		if_statinc(ifp, if_imcasts);
    720 	}
    721 
    722 	/* If the CRC is still on the packet, trim it off. */
    723 	if (m->m_flags & M_HASFCS) {
    724 		m_adj(m, -ETHER_CRC_LEN);
    725 		m->m_flags &= ~M_HASFCS;
    726 	}
    727 
    728 	if_statadd(ifp, if_ibytes, m->m_pkthdr.len);
    729 
    730 	if (!vlan_has_tag(m) && etype == ETHERTYPE_VLAN) {
    731 		m = ether_strip_vlantag(m);
    732 		if (m == NULL) {
    733 			if_statinc(ifp, if_ierrors);
    734 			return;
    735 		}
    736 
    737 		eh = mtod(m, struct ether_header *);
    738 		etype = ntohs(eh->ether_type);
    739 		ehlen = sizeof(*eh);
    740 	}
    741 
    742 	if ((m->m_flags & (M_BCAST | M_MCAST | M_PROMISC)) == 0 &&
    743 	    (ifp->if_flags & IFF_PROMISC) != 0 &&
    744 	    memcmp(CLLADDR(ifp->if_sadl), eh->ether_dhost,
    745 	     ETHER_ADDR_LEN) != 0) {
    746 		m->m_flags |= M_PROMISC;
    747 	}
    748 
    749 	if ((m->m_flags & M_PROMISC) == 0) {
    750 		if (pfil_run_hooks(ifp->if_pfil, &m, ifp, PFIL_IN) != 0)
    751 			return;
    752 		if (m == NULL)
    753 			return;
    754 
    755 		eh = mtod(m, struct ether_header *);
    756 		etype = ntohs(eh->ether_type);
    757 	}
    758 
    759 	/*
    760 	 * Processing a logical interfaces that are able
    761 	 * to configure vlan(4).
    762 	*/
    763 #if NAGR > 0
    764 	if (ifp->if_lagg != NULL &&
    765 	    __predict_true(etype != ETHERTYPE_SLOWPROTOCOLS)) {
    766 		m->m_flags &= ~M_PROMISC;
    767 		agr_input(ifp, m);
    768 		return;
    769 	}
    770 #endif
    771 
    772 	/*
    773 	 * VLAN processing.
    774 	 *
    775 	 * VLAN provides service delimiting so the frames are
    776 	 * processed before other handlings. If a VLAN interface
    777 	 * does not exist to take those frames, they're returned
    778 	 * to ether_input().
    779 	 */
    780 
    781 	if (vlan_has_tag(m)) {
    782 		if (EVL_VLANOFTAG(vlan_get_tag(m)) == 0) {
    783 			if (etype == ETHERTYPE_VLAN ||
    784 			     etype == ETHERTYPE_QINQ)
    785 				goto drop;
    786 
    787 			/* XXX we should actually use the prio value? */
    788 			m->m_flags &= ~M_VLANTAG;
    789 		} else {
    790 #if NVLAN > 0
    791 			if (ec->ec_nvlans > 0) {
    792 				m = vlan_input(ifp, m);
    793 
    794 				/* vlan_input() called ether_input() recursively */
    795 				if (m == NULL)
    796 					return;
    797 			}
    798 #endif
    799 			/* drop VLAN frames not for this port. */
    800 			goto noproto;
    801 		}
    802 	}
    803 
    804 #if NCARP > 0
    805 	if (__predict_false(ifp->if_carp && ifp->if_type != IFT_CARP)) {
    806 		/*
    807 		 * Clear M_PROMISC, in case the packet comes from a
    808 		 * vlan.
    809 		 */
    810 		m->m_flags &= ~M_PROMISC;
    811 		if (carp_input(m, (uint8_t *)&eh->ether_shost,
    812 		    (uint8_t *)&eh->ether_dhost, eh->ether_type) == 0)
    813 			return;
    814 	}
    815 #endif
    816 
    817 	/*
    818 	 * Handle protocols that expect to have the Ethernet header
    819 	 * (and possibly FCS) intact.
    820 	 */
    821 	switch (etype) {
    822 #if NPPPOE > 0
    823 	case ETHERTYPE_PPPOEDISC:
    824 		pppoedisc_input(ifp, m);
    825 		return;
    826 
    827 	case ETHERTYPE_PPPOE:
    828 		pppoe_input(ifp, m);
    829 		return;
    830 #endif
    831 
    832 	case ETHERTYPE_SLOWPROTOCOLS: {
    833 		uint8_t subtype;
    834 
    835 		if (m->m_pkthdr.len < sizeof(*eh) + sizeof(subtype))
    836 			goto error;
    837 
    838 		m_copydata(m, sizeof(*eh), sizeof(subtype), &subtype);
    839 		switch (subtype) {
    840 #if NAGR > 0
    841 		case SLOWPROTOCOLS_SUBTYPE_LACP:
    842 			if (ifp->if_lagg != NULL) {
    843 				ieee8023ad_lacp_input(ifp, m);
    844 				return;
    845 			}
    846 			break;
    847 
    848 		case SLOWPROTOCOLS_SUBTYPE_MARKER:
    849 			if (ifp->if_lagg != NULL) {
    850 				ieee8023ad_marker_input(ifp, m);
    851 				return;
    852 			}
    853 			break;
    854 #endif
    855 
    856 		default:
    857 			if (subtype == 0 || subtype > 10) {
    858 				/* illegal value */
    859 				goto noproto;
    860 			}
    861 			/* unknown subtype */
    862 			break;
    863 		}
    864 	}
    865 	/* FALLTHROUGH */
    866 	default:
    867 		if (m->m_flags & M_PROMISC)
    868 			goto drop;
    869 	}
    870 
    871 	/* If the CRC is still on the packet, trim it off. */
    872 	if (m->m_flags & M_HASFCS) {
    873 		m_adj(m, -ETHER_CRC_LEN);
    874 		m->m_flags &= ~M_HASFCS;
    875 	}
    876 
    877 	/* etype represents the size of the payload in this case */
    878 	if (etype <= ETHERMTU + sizeof(struct ether_header)) {
    879 		KASSERT(ehlen == sizeof(*eh));
    880 #if defined (LLC) || defined (NETATALK)
    881 		ether_input_llc(ifp, m, eh);
    882 		return;
    883 #else
    884 		/* ethertype of 0-1500 is regarded as noproto */
    885 		goto noproto;
    886 #endif
    887 	}
    888 
    889 	/* For ARP packets, store the source address so that
    890 	 * ARP DAD probes can be validated. */
    891 	if (etype == ETHERTYPE_ARP) {
    892 		struct m_tag *mtag;
    893 
    894 		mtag = m_tag_get(PACKET_TAG_ETHERNET_SRC, ETHER_ADDR_LEN,
    895 		    M_NOWAIT);
    896 		if (mtag != NULL) {
    897 			memcpy(mtag + 1, &eh->ether_shost, ETHER_ADDR_LEN);
    898 			m_tag_prepend(m, mtag);
    899 		}
    900 	}
    901 
    902 	/* Strip off the Ethernet header. */
    903 	m_adj(m, ehlen);
    904 
    905 	switch (etype) {
    906 #ifdef INET
    907 	case ETHERTYPE_IP:
    908 #ifdef GATEWAY
    909 		if (ipflow_fastforward(m))
    910 			return;
    911 #endif
    912 		pktq = ip_pktq;
    913 		rps_hash = atomic_load_relaxed(&ether_pktq_rps_hash_p);
    914 		break;
    915 
    916 	case ETHERTYPE_ARP:
    917 		pktq = arp_pktq;
    918 		break;
    919 
    920 	case ETHERTYPE_REVARP:
    921 		revarpinput(m);	/* XXX queue? */
    922 		return;
    923 #endif
    924 
    925 #ifdef INET6
    926 	case ETHERTYPE_IPV6:
    927 		if (__predict_false(!in6_present))
    928 			goto noproto;
    929 #ifdef GATEWAY
    930 		if (ip6flow_fastforward(&m))
    931 			return;
    932 #endif
    933 		pktq = ip6_pktq;
    934 		rps_hash = atomic_load_relaxed(&ether_pktq_rps_hash_p);
    935 		break;
    936 #endif
    937 
    938 #ifdef NETATALK
    939 	case ETHERTYPE_ATALK:
    940 		pktq = at_pktq1;
    941 		break;
    942 
    943 	case ETHERTYPE_AARP:
    944 		aarpinput(ifp, m); /* XXX queue? */
    945 		return;
    946 #endif
    947 
    948 #ifdef MPLS
    949 	case ETHERTYPE_MPLS:
    950 		pktq = mpls_pktq;
    951 		break;
    952 #endif
    953 
    954 	default:
    955 		goto noproto;
    956 	}
    957 
    958 	KASSERT(pktq != NULL);
    959 	const uint32_t h = rps_hash ? pktq_rps_hash(&rps_hash, m) : 0;
    960 	if (__predict_false(!pktq_enqueue(pktq, m, h))) {
    961 		m_freem(m);
    962 	}
    963 	return;
    964 
    965 drop:
    966 	m_freem(m);
    967 	if_statinc(ifp, if_iqdrops);
    968 	return;
    969 noproto:
    970 	m_freem(m);
    971 	if_statinc(ifp, if_noproto);
    972 	return;
    973 error:
    974 	m_freem(m);
    975 	if_statinc(ifp, if_ierrors);
    976 	return;
    977 }
    978 
    979 static void
    980 ether_bpf_mtap(struct bpf_if *bp, struct mbuf *m, u_int direction)
    981 {
    982 	struct ether_vlan_header evl;
    983 	struct m_hdr mh, md;
    984 
    985 	KASSERT(bp != NULL);
    986 
    987 	if (!vlan_has_tag(m)) {
    988 		bpf_mtap3(bp, m, direction);
    989 		return;
    990 	}
    991 
    992 	memcpy(&evl, mtod(m, char *), ETHER_HDR_LEN);
    993 	evl.evl_proto = evl.evl_encap_proto;
    994 	evl.evl_encap_proto = htons(ETHERTYPE_VLAN);
    995 	evl.evl_tag = htons(vlan_get_tag(m));
    996 
    997 	md.mh_flags = 0;
    998 	md.mh_data = m->m_data + ETHER_HDR_LEN;
    999 	md.mh_len = m->m_len - ETHER_HDR_LEN;
   1000 	md.mh_next = m->m_next;
   1001 
   1002 	mh.mh_flags = 0;
   1003 	mh.mh_data = (char *)&evl;
   1004 	mh.mh_len = sizeof(evl);
   1005 	mh.mh_next = (struct mbuf *)&md;
   1006 
   1007 	bpf_mtap3(bp, (struct mbuf *)&mh, direction);
   1008 }
   1009 
   1010 /*
   1011  * Convert Ethernet address to printable (loggable) representation.
   1012  */
   1013 char *
   1014 ether_sprintf(const u_char *ap)
   1015 {
   1016 	static char etherbuf[3 * ETHER_ADDR_LEN];
   1017 	return ether_snprintf(etherbuf, sizeof(etherbuf), ap);
   1018 }
   1019 
   1020 char *
   1021 ether_snprintf(char *buf, size_t len, const u_char *ap)
   1022 {
   1023 	char *cp = buf;
   1024 	size_t i;
   1025 
   1026 	for (i = 0; i < len / 3; i++) {
   1027 		*cp++ = hexdigits[*ap >> 4];
   1028 		*cp++ = hexdigits[*ap++ & 0xf];
   1029 		*cp++ = ':';
   1030 	}
   1031 	*--cp = '\0';
   1032 	return buf;
   1033 }
   1034 
   1035 /*
   1036  * Perform common duties while attaching to interface list
   1037  */
   1038 void
   1039 ether_ifattach(struct ifnet *ifp, const uint8_t *lla)
   1040 {
   1041 	struct ethercom *ec = (struct ethercom *)ifp;
   1042 	char xnamebuf[HOOKNAMSIZ];
   1043 
   1044 	if (lla != NULL && ETHER_IS_MULTICAST(lla))
   1045 		aprint_error("The multicast bit is set in the MAC address. "
   1046 			"It's wrong.\n");
   1047 
   1048 	ifp->if_type = IFT_ETHER;
   1049 	ifp->if_hdrlen = ETHER_HDR_LEN;
   1050 	ifp->if_dlt = DLT_EN10MB;
   1051 	ifp->if_mtu = ETHERMTU;
   1052 	ifp->if_output = ether_output;
   1053 	ifp->_if_input = ether_input;
   1054 	if (ec->ec_capabilities & ETHERCAP_VLAN_HWTAGGING)
   1055 		ifp->if_bpf_mtap = ether_bpf_mtap;
   1056 	if (ifp->if_baudrate == 0)
   1057 		ifp->if_baudrate = IF_Mbps(10);		/* just a default */
   1058 
   1059 	if (lla != NULL)
   1060 		if_set_sadl(ifp, lla, ETHER_ADDR_LEN, !ETHER_IS_LOCAL(lla));
   1061 
   1062 	LIST_INIT(&ec->ec_multiaddrs);
   1063 	SIMPLEQ_INIT(&ec->ec_vids);
   1064 	ec->ec_lock = mutex_obj_alloc(MUTEX_DEFAULT, IPL_NET);
   1065 	ec->ec_flags = 0;
   1066 	ifp->if_broadcastaddr = etherbroadcastaddr;
   1067 	bpf_attach(ifp, DLT_EN10MB, sizeof(struct ether_header));
   1068 	snprintf(xnamebuf, sizeof(xnamebuf),
   1069 	    "%s-ether_ifdetachhooks", ifp->if_xname);
   1070 	ec->ec_ifdetach_hooks = simplehook_create(IPL_NET, xnamebuf);
   1071 #ifdef MBUFTRACE
   1072 	mowner_init_owner(&ec->ec_tx_mowner, ifp->if_xname, "tx");
   1073 	mowner_init_owner(&ec->ec_rx_mowner, ifp->if_xname, "rx");
   1074 	MOWNER_ATTACH(&ec->ec_tx_mowner);
   1075 	MOWNER_ATTACH(&ec->ec_rx_mowner);
   1076 	ifp->if_mowner = &ec->ec_tx_mowner;
   1077 #endif
   1078 }
   1079 
   1080 void
   1081 ether_ifdetach(struct ifnet *ifp)
   1082 {
   1083 	struct ethercom *ec = (void *) ifp;
   1084 	struct ether_multi *enm;
   1085 
   1086 	IFNET_ASSERT_UNLOCKED(ifp);
   1087 	/*
   1088 	 * Prevent further calls to ioctl (for example turning off
   1089 	 * promiscuous mode from the bridge code), which eventually can
   1090 	 * call if_init() which can cause panics because the interface
   1091 	 * is in the process of being detached. Return device not configured
   1092 	 * instead.
   1093 	 */
   1094 	ifp->if_ioctl = __FPTRCAST(int (*)(struct ifnet *, u_long, void *),
   1095 	    enxio);
   1096 
   1097 	simplehook_dohooks(ec->ec_ifdetach_hooks);
   1098 	KASSERT(!simplehook_has_hooks(ec->ec_ifdetach_hooks));
   1099 	simplehook_destroy(ec->ec_ifdetach_hooks);
   1100 
   1101 	bpf_detach(ifp);
   1102 
   1103 	ETHER_LOCK(ec);
   1104 	KASSERT(ec->ec_nvlans == 0);
   1105 	while ((enm = LIST_FIRST(&ec->ec_multiaddrs)) != NULL) {
   1106 		LIST_REMOVE(enm, enm_list);
   1107 		kmem_free(enm, sizeof(*enm));
   1108 		ec->ec_multicnt--;
   1109 	}
   1110 	ETHER_UNLOCK(ec);
   1111 
   1112 	mutex_obj_free(ec->ec_lock);
   1113 	ec->ec_lock = NULL;
   1114 
   1115 	ifp->if_mowner = NULL;
   1116 	MOWNER_DETACH(&ec->ec_rx_mowner);
   1117 	MOWNER_DETACH(&ec->ec_tx_mowner);
   1118 }
   1119 
   1120 void *
   1121 ether_ifdetachhook_establish(struct ifnet *ifp,
   1122     void (*fn)(void *), void *arg)
   1123 {
   1124 	struct ethercom *ec;
   1125 	khook_t *hk;
   1126 
   1127 	if (ifp->if_type != IFT_ETHER)
   1128 		return NULL;
   1129 
   1130 	ec = (struct ethercom *)ifp;
   1131 	hk = simplehook_establish(ec->ec_ifdetach_hooks,
   1132 	    fn, arg);
   1133 
   1134 	return (void *)hk;
   1135 }
   1136 
   1137 void
   1138 ether_ifdetachhook_disestablish(struct ifnet *ifp,
   1139     void *vhook, kmutex_t *lock)
   1140 {
   1141 	struct ethercom *ec;
   1142 
   1143 	if (vhook == NULL)
   1144 		return;
   1145 
   1146 	ec = (struct ethercom *)ifp;
   1147 	simplehook_disestablish(ec->ec_ifdetach_hooks, vhook, lock);
   1148 }
   1149 
   1150 #if 0
   1151 /*
   1152  * This is for reference.  We have a table-driven version
   1153  * of the little-endian crc32 generator, which is faster
   1154  * than the double-loop.
   1155  */
   1156 uint32_t
   1157 ether_crc32_le(const uint8_t *buf, size_t len)
   1158 {
   1159 	uint32_t c, crc, carry;
   1160 	size_t i, j;
   1161 
   1162 	crc = 0xffffffffU;	/* initial value */
   1163 
   1164 	for (i = 0; i < len; i++) {
   1165 		c = buf[i];
   1166 		for (j = 0; j < 8; j++) {
   1167 			carry = ((crc & 0x01) ? 1 : 0) ^ (c & 0x01);
   1168 			crc >>= 1;
   1169 			c >>= 1;
   1170 			if (carry)
   1171 				crc = (crc ^ ETHER_CRC_POLY_LE);
   1172 		}
   1173 	}
   1174 
   1175 	return (crc);
   1176 }
   1177 #else
   1178 uint32_t
   1179 ether_crc32_le(const uint8_t *buf, size_t len)
   1180 {
   1181 	static const uint32_t crctab[] = {
   1182 		0x00000000, 0x1db71064, 0x3b6e20c8, 0x26d930ac,
   1183 		0x76dc4190, 0x6b6b51f4, 0x4db26158, 0x5005713c,
   1184 		0xedb88320, 0xf00f9344, 0xd6d6a3e8, 0xcb61b38c,
   1185 		0x9b64c2b0, 0x86d3d2d4, 0xa00ae278, 0xbdbdf21c
   1186 	};
   1187 	uint32_t crc;
   1188 	size_t i;
   1189 
   1190 	crc = 0xffffffffU;	/* initial value */
   1191 
   1192 	for (i = 0; i < len; i++) {
   1193 		crc ^= buf[i];
   1194 		crc = (crc >> 4) ^ crctab[crc & 0xf];
   1195 		crc = (crc >> 4) ^ crctab[crc & 0xf];
   1196 	}
   1197 
   1198 	return (crc);
   1199 }
   1200 #endif
   1201 
   1202 uint32_t
   1203 ether_crc32_be(const uint8_t *buf, size_t len)
   1204 {
   1205 	uint32_t c, crc, carry;
   1206 	size_t i, j;
   1207 
   1208 	crc = 0xffffffffU;	/* initial value */
   1209 
   1210 	for (i = 0; i < len; i++) {
   1211 		c = buf[i];
   1212 		for (j = 0; j < 8; j++) {
   1213 			carry = ((crc & 0x80000000U) ? 1 : 0) ^ (c & 0x01);
   1214 			crc <<= 1;
   1215 			c >>= 1;
   1216 			if (carry)
   1217 				crc = (crc ^ ETHER_CRC_POLY_BE) | carry;
   1218 		}
   1219 	}
   1220 
   1221 	return (crc);
   1222 }
   1223 
   1224 #ifdef INET
   1225 const uint8_t ether_ipmulticast_min[ETHER_ADDR_LEN] =
   1226     { 0x01, 0x00, 0x5e, 0x00, 0x00, 0x00 };
   1227 const uint8_t ether_ipmulticast_max[ETHER_ADDR_LEN] =
   1228     { 0x01, 0x00, 0x5e, 0x7f, 0xff, 0xff };
   1229 #endif
   1230 #ifdef INET6
   1231 const uint8_t ether_ip6multicast_min[ETHER_ADDR_LEN] =
   1232     { 0x33, 0x33, 0x00, 0x00, 0x00, 0x00 };
   1233 const uint8_t ether_ip6multicast_max[ETHER_ADDR_LEN] =
   1234     { 0x33, 0x33, 0xff, 0xff, 0xff, 0xff };
   1235 #endif
   1236 
   1237 /*
   1238  * ether_aton implementation, not using a static buffer.
   1239  */
   1240 int
   1241 ether_aton_r(u_char *dest, size_t len, const char *str)
   1242 {
   1243 	const u_char *cp = (const void *)str;
   1244 	u_char *ep;
   1245 
   1246 #define atox(c)	(((c) <= '9') ? ((c) - '0') : ((toupper(c) - 'A') + 10))
   1247 
   1248 	if (len < ETHER_ADDR_LEN)
   1249 		return ENOSPC;
   1250 
   1251 	ep = dest + ETHER_ADDR_LEN;
   1252 
   1253 	while (*cp) {
   1254 		if (!isxdigit(*cp))
   1255 			return EINVAL;
   1256 
   1257 		*dest = atox(*cp);
   1258 		cp++;
   1259 		if (isxdigit(*cp)) {
   1260 			*dest = (*dest << 4) | atox(*cp);
   1261 			cp++;
   1262 		}
   1263 		dest++;
   1264 
   1265 		if (dest == ep)
   1266 			return (*cp == '\0') ? 0 : ENAMETOOLONG;
   1267 
   1268 		switch (*cp) {
   1269 		case ':':
   1270 		case '-':
   1271 		case '.':
   1272 			cp++;
   1273 			break;
   1274 		}
   1275 	}
   1276 	return ENOBUFS;
   1277 }
   1278 
   1279 /*
   1280  * Convert a sockaddr into an Ethernet address or range of Ethernet
   1281  * addresses.
   1282  */
   1283 int
   1284 ether_multiaddr(const struct sockaddr *sa, uint8_t addrlo[ETHER_ADDR_LEN],
   1285     uint8_t addrhi[ETHER_ADDR_LEN])
   1286 {
   1287 #ifdef INET
   1288 	const struct sockaddr_in *sin;
   1289 #endif
   1290 #ifdef INET6
   1291 	const struct sockaddr_in6 *sin6;
   1292 #endif
   1293 
   1294 	switch (sa->sa_family) {
   1295 
   1296 	case AF_UNSPEC:
   1297 		memcpy(addrlo, sa->sa_data, ETHER_ADDR_LEN);
   1298 		memcpy(addrhi, addrlo, ETHER_ADDR_LEN);
   1299 		break;
   1300 
   1301 #ifdef INET
   1302 	case AF_INET:
   1303 		sin = satocsin(sa);
   1304 		if (sin->sin_addr.s_addr == INADDR_ANY) {
   1305 			/*
   1306 			 * An IP address of INADDR_ANY means listen to
   1307 			 * or stop listening to all of the Ethernet
   1308 			 * multicast addresses used for IP.
   1309 			 * (This is for the sake of IP multicast routers.)
   1310 			 */
   1311 			memcpy(addrlo, ether_ipmulticast_min, ETHER_ADDR_LEN);
   1312 			memcpy(addrhi, ether_ipmulticast_max, ETHER_ADDR_LEN);
   1313 		} else {
   1314 			ETHER_MAP_IP_MULTICAST(&sin->sin_addr, addrlo);
   1315 			memcpy(addrhi, addrlo, ETHER_ADDR_LEN);
   1316 		}
   1317 		break;
   1318 #endif
   1319 #ifdef INET6
   1320 	case AF_INET6:
   1321 		sin6 = satocsin6(sa);
   1322 		if (IN6_IS_ADDR_UNSPECIFIED(&sin6->sin6_addr)) {
   1323 			/*
   1324 			 * An IP6 address of 0 means listen to or stop
   1325 			 * listening to all of the Ethernet multicast
   1326 			 * address used for IP6.
   1327 			 * (This is used for multicast routers.)
   1328 			 */
   1329 			memcpy(addrlo, ether_ip6multicast_min, ETHER_ADDR_LEN);
   1330 			memcpy(addrhi, ether_ip6multicast_max, ETHER_ADDR_LEN);
   1331 		} else {
   1332 			ETHER_MAP_IPV6_MULTICAST(&sin6->sin6_addr, addrlo);
   1333 			memcpy(addrhi, addrlo, ETHER_ADDR_LEN);
   1334 		}
   1335 		break;
   1336 #endif
   1337 
   1338 	default:
   1339 		return EAFNOSUPPORT;
   1340 	}
   1341 	return 0;
   1342 }
   1343 
   1344 /*
   1345  * Add an Ethernet multicast address or range of addresses to the list for a
   1346  * given interface.
   1347  */
   1348 int
   1349 ether_addmulti(const struct sockaddr *sa, struct ethercom *ec)
   1350 {
   1351 	struct ether_multi *enm, *_enm;
   1352 	u_char addrlo[ETHER_ADDR_LEN];
   1353 	u_char addrhi[ETHER_ADDR_LEN];
   1354 	int error = 0;
   1355 
   1356 	/* Allocate out of lock */
   1357 	enm = kmem_alloc(sizeof(*enm), KM_SLEEP);
   1358 
   1359 	ETHER_LOCK(ec);
   1360 	error = ether_multiaddr(sa, addrlo, addrhi);
   1361 	if (error != 0)
   1362 		goto out;
   1363 
   1364 	/*
   1365 	 * Verify that we have valid Ethernet multicast addresses.
   1366 	 */
   1367 	if (!ETHER_IS_MULTICAST(addrlo) || !ETHER_IS_MULTICAST(addrhi)) {
   1368 		error = EINVAL;
   1369 		goto out;
   1370 	}
   1371 
   1372 	/*
   1373 	 * See if the address range is already in the list.
   1374 	 */
   1375 	_enm = ether_lookup_multi(addrlo, addrhi, ec);
   1376 	if (_enm != NULL) {
   1377 		/*
   1378 		 * Found it; just increment the reference count.
   1379 		 */
   1380 		++_enm->enm_refcount;
   1381 		error = 0;
   1382 		goto out;
   1383 	}
   1384 
   1385 	/*
   1386 	 * Link a new multicast record into the interface's multicast list.
   1387 	 */
   1388 	memcpy(enm->enm_addrlo, addrlo, ETHER_ADDR_LEN);
   1389 	memcpy(enm->enm_addrhi, addrhi, ETHER_ADDR_LEN);
   1390 	enm->enm_refcount = 1;
   1391 	LIST_INSERT_HEAD(&ec->ec_multiaddrs, enm, enm_list);
   1392 	ec->ec_multicnt++;
   1393 
   1394 	/*
   1395 	 * Return ENETRESET to inform the driver that the list has changed
   1396 	 * and its reception filter should be adjusted accordingly.
   1397 	 */
   1398 	error = ENETRESET;
   1399 	enm = NULL;
   1400 
   1401 out:
   1402 	ETHER_UNLOCK(ec);
   1403 	if (enm != NULL)
   1404 		kmem_free(enm, sizeof(*enm));
   1405 	return error;
   1406 }
   1407 
   1408 /*
   1409  * Delete a multicast address record.
   1410  */
   1411 int
   1412 ether_delmulti(const struct sockaddr *sa, struct ethercom *ec)
   1413 {
   1414 	struct ether_multi *enm;
   1415 	u_char addrlo[ETHER_ADDR_LEN];
   1416 	u_char addrhi[ETHER_ADDR_LEN];
   1417 	int error;
   1418 
   1419 	ETHER_LOCK(ec);
   1420 	error = ether_multiaddr(sa, addrlo, addrhi);
   1421 	if (error != 0)
   1422 		goto error;
   1423 
   1424 	/*
   1425 	 * Look up the address in our list.
   1426 	 */
   1427 	enm = ether_lookup_multi(addrlo, addrhi, ec);
   1428 	if (enm == NULL) {
   1429 		error = ENXIO;
   1430 		goto error;
   1431 	}
   1432 	if (--enm->enm_refcount != 0) {
   1433 		/*
   1434 		 * Still some claims to this record.
   1435 		 */
   1436 		error = 0;
   1437 		goto error;
   1438 	}
   1439 
   1440 	/*
   1441 	 * No remaining claims to this record; unlink and free it.
   1442 	 */
   1443 	LIST_REMOVE(enm, enm_list);
   1444 	ec->ec_multicnt--;
   1445 	ETHER_UNLOCK(ec);
   1446 	kmem_free(enm, sizeof(*enm));
   1447 
   1448 	/*
   1449 	 * Return ENETRESET to inform the driver that the list has changed
   1450 	 * and its reception filter should be adjusted accordingly.
   1451 	 */
   1452 	return ENETRESET;
   1453 
   1454 error:
   1455 	ETHER_UNLOCK(ec);
   1456 	return error;
   1457 }
   1458 
   1459 void
   1460 ether_set_ifflags_cb(struct ethercom *ec, ether_cb_t cb)
   1461 {
   1462 	ec->ec_ifflags_cb = cb;
   1463 }
   1464 
   1465 void
   1466 ether_set_vlan_cb(struct ethercom *ec, ether_vlancb_t cb)
   1467 {
   1468 
   1469 	ec->ec_vlan_cb = cb;
   1470 }
   1471 
   1472 static int
   1473 ether_ioctl_reinit(struct ethercom *ec)
   1474 {
   1475 	struct ifnet *ifp = &ec->ec_if;
   1476 	int error;
   1477 
   1478 	KASSERTMSG(IFNET_LOCKED(ifp), "%s", ifp->if_xname);
   1479 
   1480 	switch (ifp->if_flags & (IFF_UP | IFF_RUNNING)) {
   1481 	case IFF_RUNNING:
   1482 		/*
   1483 		 * If interface is marked down and it is running,
   1484 		 * then stop and disable it.
   1485 		 */
   1486 		if_stop(ifp, 1);
   1487 		break;
   1488 	case IFF_UP:
   1489 		/*
   1490 		 * If interface is marked up and it is stopped, then
   1491 		 * start it.
   1492 		 */
   1493 		return if_init(ifp);
   1494 	case IFF_UP | IFF_RUNNING:
   1495 		error = 0;
   1496 		if (ec->ec_ifflags_cb != NULL) {
   1497 			error = (*ec->ec_ifflags_cb)(ec);
   1498 			if (error == ENETRESET) {
   1499 				/*
   1500 				 * Reset the interface to pick up
   1501 				 * changes in any other flags that
   1502 				 * affect the hardware state.
   1503 				 */
   1504 				return if_init(ifp);
   1505 			}
   1506 		} else
   1507 			error = if_init(ifp);
   1508 		return error;
   1509 	case 0:
   1510 		break;
   1511 	}
   1512 
   1513 	return 0;
   1514 }
   1515 
   1516 /*
   1517  * Common ioctls for Ethernet interfaces.  Note, we must be
   1518  * called at splnet().
   1519  */
   1520 int
   1521 ether_ioctl(struct ifnet *ifp, u_long cmd, void *data)
   1522 {
   1523 	struct ethercom *ec = (void *)ifp;
   1524 	struct eccapreq *eccr;
   1525 	struct ifreq *ifr = (struct ifreq *)data;
   1526 	struct if_laddrreq *iflr = data;
   1527 	const struct sockaddr_dl *sdl;
   1528 	static const uint8_t zero[ETHER_ADDR_LEN];
   1529 	int error;
   1530 
   1531 	switch (cmd) {
   1532 	case SIOCINITIFADDR:
   1533 	    {
   1534 		struct ifaddr *ifa = (struct ifaddr *)data;
   1535 		if (ifa->ifa_addr->sa_family != AF_LINK
   1536 		    && (ifp->if_flags & (IFF_UP | IFF_RUNNING)) !=
   1537 		       (IFF_UP | IFF_RUNNING)) {
   1538 			ifp->if_flags |= IFF_UP;
   1539 			if ((error = if_init(ifp)) != 0)
   1540 				return error;
   1541 		}
   1542 #ifdef INET
   1543 		if (ifa->ifa_addr->sa_family == AF_INET)
   1544 			arp_ifinit(ifp, ifa);
   1545 #endif
   1546 		return 0;
   1547 	    }
   1548 
   1549 	case SIOCSIFMTU:
   1550 	    {
   1551 		int maxmtu;
   1552 
   1553 		if (ec->ec_capabilities & ETHERCAP_JUMBO_MTU)
   1554 			maxmtu = ETHERMTU_JUMBO;
   1555 		else
   1556 			maxmtu = ETHERMTU;
   1557 
   1558 		if (ifr->ifr_mtu < ETHERMIN || ifr->ifr_mtu > maxmtu)
   1559 			return EINVAL;
   1560 		else if ((error = ifioctl_common(ifp, cmd, data)) != ENETRESET)
   1561 			return error;
   1562 		else if (ifp->if_flags & IFF_UP) {
   1563 			/* Make sure the device notices the MTU change. */
   1564 			return if_init(ifp);
   1565 		} else
   1566 			return 0;
   1567 	    }
   1568 
   1569 	case SIOCSIFFLAGS:
   1570 		if ((error = ifioctl_common(ifp, cmd, data)) != 0)
   1571 			return error;
   1572 		return ether_ioctl_reinit(ec);
   1573 	case SIOCGIFFLAGS:
   1574 		error = ifioctl_common(ifp, cmd, data);
   1575 		if (error == 0) {
   1576 			/* Set IFF_ALLMULTI for backcompat */
   1577 			ifr->ifr_flags |= (ec->ec_flags & ETHER_F_ALLMULTI) ?
   1578 			    IFF_ALLMULTI : 0;
   1579 		}
   1580 		return error;
   1581 	case SIOCGETHERCAP:
   1582 		eccr = (struct eccapreq *)data;
   1583 		eccr->eccr_capabilities = ec->ec_capabilities;
   1584 		eccr->eccr_capenable = ec->ec_capenable;
   1585 		return 0;
   1586 	case SIOCSETHERCAP:
   1587 		eccr = (struct eccapreq *)data;
   1588 		if ((eccr->eccr_capenable & ~ec->ec_capabilities) != 0)
   1589 			return EINVAL;
   1590 		if (eccr->eccr_capenable == ec->ec_capenable)
   1591 			return 0;
   1592 #if 0 /* notyet */
   1593 		ec->ec_capenable = (ec->ec_capenable & ETHERCAP_CANTCHANGE)
   1594 		    | (eccr->eccr_capenable & ~ETHERCAP_CANTCHANGE);
   1595 #else
   1596 		ec->ec_capenable = eccr->eccr_capenable;
   1597 #endif
   1598 		return ether_ioctl_reinit(ec);
   1599 	case SIOCADDMULTI:
   1600 		return ether_addmulti(ifreq_getaddr(cmd, ifr), ec);
   1601 	case SIOCDELMULTI:
   1602 		return ether_delmulti(ifreq_getaddr(cmd, ifr), ec);
   1603 	case SIOCSIFMEDIA:
   1604 	case SIOCGIFMEDIA:
   1605 		if (ec->ec_mii != NULL)
   1606 			return ifmedia_ioctl(ifp, ifr, &ec->ec_mii->mii_media,
   1607 			    cmd);
   1608 		else if (ec->ec_ifmedia != NULL)
   1609 			return ifmedia_ioctl(ifp, ifr, ec->ec_ifmedia, cmd);
   1610 		else
   1611 			return ENOTTY;
   1612 		break;
   1613 	case SIOCALIFADDR:
   1614 		sdl = satocsdl(sstocsa(&iflr->addr));
   1615 		if (sdl->sdl_family != AF_LINK)
   1616 			;
   1617 		else if (ETHER_IS_MULTICAST(CLLADDR(sdl)))
   1618 			return EINVAL;
   1619 		else if (memcmp(zero, CLLADDR(sdl), sizeof(zero)) == 0)
   1620 			return EINVAL;
   1621 		/*FALLTHROUGH*/
   1622 	default:
   1623 		return ifioctl_common(ifp, cmd, data);
   1624 	}
   1625 	return 0;
   1626 }
   1627 
   1628 /*
   1629  * Enable/disable passing VLAN packets if the parent interface supports it.
   1630  * Return:
   1631  * 	 0: Ok
   1632  *	-1: Parent interface does not support vlans
   1633  *	>0: Error
   1634  */
   1635 int
   1636 ether_enable_vlan_mtu(struct ifnet *ifp)
   1637 {
   1638 	int error;
   1639 	struct ethercom *ec = (void *)ifp;
   1640 
   1641 	/* Parent does not support VLAN's */
   1642 	if ((ec->ec_capabilities & ETHERCAP_VLAN_MTU) == 0)
   1643 		return -1;
   1644 
   1645 	/*
   1646 	 * Parent supports the VLAN_MTU capability,
   1647 	 * i.e. can Tx/Rx larger than ETHER_MAX_LEN frames;
   1648 	 * enable it.
   1649 	 */
   1650 	ec->ec_capenable |= ETHERCAP_VLAN_MTU;
   1651 
   1652 	/* Interface is down, defer for later */
   1653 	if ((ifp->if_flags & IFF_UP) == 0)
   1654 		return 0;
   1655 
   1656 	if ((error = if_flags_set(ifp, ifp->if_flags)) == 0)
   1657 		return 0;
   1658 
   1659 	ec->ec_capenable &= ~ETHERCAP_VLAN_MTU;
   1660 	return error;
   1661 }
   1662 
   1663 int
   1664 ether_disable_vlan_mtu(struct ifnet *ifp)
   1665 {
   1666 	int error;
   1667 	struct ethercom *ec = (void *)ifp;
   1668 
   1669 	/* We still have VLAN's, defer for later */
   1670 	if (ec->ec_nvlans != 0)
   1671 		return 0;
   1672 
   1673 	/* Parent does not support VLAB's, nothing to do. */
   1674 	if ((ec->ec_capenable & ETHERCAP_VLAN_MTU) == 0)
   1675 		return -1;
   1676 
   1677 	/*
   1678 	 * Disable Tx/Rx of VLAN-sized frames.
   1679 	 */
   1680 	ec->ec_capenable &= ~ETHERCAP_VLAN_MTU;
   1681 
   1682 	/* Interface is down, defer for later */
   1683 	if ((ifp->if_flags & IFF_UP) == 0)
   1684 		return 0;
   1685 
   1686 	if ((error = if_flags_set(ifp, ifp->if_flags)) == 0)
   1687 		return 0;
   1688 
   1689 	ec->ec_capenable |= ETHERCAP_VLAN_MTU;
   1690 	return error;
   1691 }
   1692 
   1693 /*
   1694  * Add and delete VLAN TAG
   1695  */
   1696 int
   1697 ether_add_vlantag(struct ifnet *ifp, uint16_t vtag, bool *vlanmtu_status)
   1698 {
   1699 	struct ethercom *ec = (void *)ifp;
   1700 	struct vlanid_list *vidp;
   1701 	bool vlanmtu_enabled;
   1702 	uint16_t vid = EVL_VLANOFTAG(vtag);
   1703 	int error;
   1704 
   1705 	vlanmtu_enabled = false;
   1706 
   1707 	/* Add a vid to the list */
   1708 	vidp = kmem_alloc(sizeof(*vidp), KM_SLEEP);
   1709 	vidp->vid = vid;
   1710 
   1711 	ETHER_LOCK(ec);
   1712 	ec->ec_nvlans++;
   1713 	SIMPLEQ_INSERT_TAIL(&ec->ec_vids, vidp, vid_list);
   1714 	ETHER_UNLOCK(ec);
   1715 
   1716 	if (ec->ec_nvlans == 1) {
   1717 		IFNET_LOCK(ifp);
   1718 		error = ether_enable_vlan_mtu(ifp);
   1719 		IFNET_UNLOCK(ifp);
   1720 
   1721 		if (error == 0) {
   1722 			vlanmtu_enabled = true;
   1723 		} else if (error != -1) {
   1724 			goto fail;
   1725 		}
   1726 	}
   1727 
   1728 	if (ec->ec_vlan_cb != NULL) {
   1729 		error = (*ec->ec_vlan_cb)(ec, vid, true);
   1730 		if (error != 0)
   1731 			goto fail;
   1732 	}
   1733 
   1734 	if (vlanmtu_status != NULL)
   1735 		*vlanmtu_status = vlanmtu_enabled;
   1736 
   1737 	return 0;
   1738 fail:
   1739 	ETHER_LOCK(ec);
   1740 	ec->ec_nvlans--;
   1741 	SIMPLEQ_REMOVE(&ec->ec_vids, vidp, vlanid_list, vid_list);
   1742 	ETHER_UNLOCK(ec);
   1743 
   1744 	if (vlanmtu_enabled) {
   1745 		IFNET_LOCK(ifp);
   1746 		(void)ether_disable_vlan_mtu(ifp);
   1747 		IFNET_UNLOCK(ifp);
   1748 	}
   1749 
   1750 	kmem_free(vidp, sizeof(*vidp));
   1751 
   1752 	return error;
   1753 }
   1754 
   1755 int
   1756 ether_del_vlantag(struct ifnet *ifp, uint16_t vtag)
   1757 {
   1758 	struct ethercom *ec = (void *)ifp;
   1759 	struct vlanid_list *vidp;
   1760 	uint16_t vid = EVL_VLANOFTAG(vtag);
   1761 
   1762 	ETHER_LOCK(ec);
   1763 	SIMPLEQ_FOREACH(vidp, &ec->ec_vids, vid_list) {
   1764 		if (vidp->vid == vid) {
   1765 			SIMPLEQ_REMOVE(&ec->ec_vids, vidp,
   1766 			    vlanid_list, vid_list);
   1767 			ec->ec_nvlans--;
   1768 			break;
   1769 		}
   1770 	}
   1771 	ETHER_UNLOCK(ec);
   1772 
   1773 	if (vidp == NULL)
   1774 		return ENOENT;
   1775 
   1776 	if (ec->ec_vlan_cb != NULL) {
   1777 		(void)(*ec->ec_vlan_cb)(ec, vidp->vid, false);
   1778 	}
   1779 
   1780 	if (ec->ec_nvlans == 0) {
   1781 		IFNET_LOCK(ifp);
   1782 		(void)ether_disable_vlan_mtu(ifp);
   1783 		IFNET_UNLOCK(ifp);
   1784 	}
   1785 
   1786 	kmem_free(vidp, sizeof(*vidp));
   1787 
   1788 	return 0;
   1789 }
   1790 
   1791 int
   1792 ether_inject_vlantag(struct mbuf **mp, uint16_t etype, uint16_t tag)
   1793 {
   1794 	static const size_t min_data_len =
   1795 	    ETHER_MIN_LEN - ETHER_CRC_LEN + ETHER_VLAN_ENCAP_LEN;
   1796 	/* Used to pad ethernet frames with < ETHER_MIN_LEN bytes */
   1797 	static const char vlan_zero_pad_buff[ETHER_MIN_LEN] = { 0 };
   1798 
   1799 	struct ether_vlan_header *evl;
   1800 	struct mbuf *m = *mp;
   1801 	int error;
   1802 
   1803 	error = 0;
   1804 
   1805 	M_PREPEND(m, ETHER_VLAN_ENCAP_LEN, M_DONTWAIT);
   1806 	if (m == NULL) {
   1807 		error = ENOBUFS;
   1808 		goto out;
   1809 	}
   1810 
   1811 	if (m->m_len < sizeof(*evl)) {
   1812 		m = m_pullup(m, sizeof(*evl));
   1813 		if (m == NULL) {
   1814 			error = ENOBUFS;
   1815 			goto out;
   1816 		}
   1817 	}
   1818 
   1819 	/*
   1820 	 * Transform the Ethernet header into an
   1821 	 * Ethernet header with 802.1Q encapsulation.
   1822 	 */
   1823 	memmove(mtod(m, void *),
   1824 	    mtod(m, char *) + ETHER_VLAN_ENCAP_LEN,
   1825 	    sizeof(struct ether_header));
   1826 	evl = mtod(m, struct ether_vlan_header *);
   1827 	evl->evl_proto = evl->evl_encap_proto;
   1828 	evl->evl_encap_proto = htons(etype);
   1829 	evl->evl_tag = htons(tag);
   1830 
   1831 	/*
   1832 	 * To cater for VLAN-aware layer 2 ethernet
   1833 	 * switches which may need to strip the tag
   1834 	 * before forwarding the packet, make sure
   1835 	 * the packet+tag is at least 68 bytes long.
   1836 	 * This is necessary because our parent will
   1837 	 * only pad to 64 bytes (ETHER_MIN_LEN) and
   1838 	 * some switches will not pad by themselves
   1839 	 * after deleting a tag.
   1840 	 */
   1841 	if (m->m_pkthdr.len < min_data_len) {
   1842 		m_copyback(m, m->m_pkthdr.len,
   1843 		    min_data_len - m->m_pkthdr.len,
   1844 		    vlan_zero_pad_buff);
   1845 	}
   1846 
   1847 	m->m_flags &= ~M_VLANTAG;
   1848 
   1849 out:
   1850 	*mp = m;
   1851 	return error;
   1852 }
   1853 
   1854 struct mbuf *
   1855 ether_strip_vlantag(struct mbuf *m)
   1856 {
   1857 	struct ether_vlan_header *evl;
   1858 
   1859 	if (m->m_len < sizeof(*evl) &&
   1860 	    (m = m_pullup(m, sizeof(*evl))) == NULL) {
   1861 		return NULL;
   1862 	}
   1863 
   1864 	if (m_makewritable(&m, 0, sizeof(*evl), M_DONTWAIT)) {
   1865 		m_freem(m);
   1866 		return NULL;
   1867 	}
   1868 
   1869 	evl = mtod(m, struct ether_vlan_header *);
   1870 	KASSERT(ntohs(evl->evl_encap_proto) == ETHERTYPE_VLAN);
   1871 
   1872 	vlan_set_tag(m, ntohs(evl->evl_tag));
   1873 
   1874 	/*
   1875 	 * Restore the original ethertype.  We'll remove
   1876 	 * the encapsulation after we've found the vlan
   1877 	 * interface corresponding to the tag.
   1878 	 */
   1879 	evl->evl_encap_proto = evl->evl_proto;
   1880 
   1881 	/*
   1882 	 * Remove the encapsulation header and append tag.
   1883 	 * The original header has already been fixed up above.
   1884 	 */
   1885 	vlan_set_tag(m, ntohs(evl->evl_tag));
   1886 	memmove((char *)evl + ETHER_VLAN_ENCAP_LEN, evl,
   1887 	    offsetof(struct ether_vlan_header, evl_encap_proto));
   1888 	m_adj(m, ETHER_VLAN_ENCAP_LEN);
   1889 
   1890 	return m;
   1891 }
   1892 
   1893 static int
   1894 ether_multicast_sysctl(SYSCTLFN_ARGS)
   1895 {
   1896 	struct ether_multi *enm;
   1897 	struct ifnet *ifp;
   1898 	struct ethercom *ec;
   1899 	int error = 0;
   1900 	size_t written;
   1901 	struct psref psref;
   1902 	int bound;
   1903 	unsigned int multicnt;
   1904 	struct ether_multi_sysctl *addrs;
   1905 	int i;
   1906 
   1907 	if (namelen != 1)
   1908 		return EINVAL;
   1909 
   1910 	bound = curlwp_bind();
   1911 	ifp = if_get_byindex(name[0], &psref);
   1912 	if (ifp == NULL) {
   1913 		error = ENODEV;
   1914 		goto out;
   1915 	}
   1916 	if (ifp->if_type != IFT_ETHER) {
   1917 		if_put(ifp, &psref);
   1918 		*oldlenp = 0;
   1919 		goto out;
   1920 	}
   1921 	ec = (struct ethercom *)ifp;
   1922 
   1923 	if (oldp == NULL) {
   1924 		if_put(ifp, &psref);
   1925 		*oldlenp = ec->ec_multicnt * sizeof(*addrs);
   1926 		goto out;
   1927 	}
   1928 
   1929 	/*
   1930 	 * ec->ec_lock is a spin mutex so we cannot call sysctl_copyout, which
   1931 	 * is sleepable, while holding it. Copy data to a local buffer first
   1932 	 * with the lock taken and then call sysctl_copyout without holding it.
   1933 	 */
   1934 retry:
   1935 	multicnt = ec->ec_multicnt;
   1936 
   1937 	if (multicnt == 0) {
   1938 		if_put(ifp, &psref);
   1939 		*oldlenp = 0;
   1940 		goto out;
   1941 	}
   1942 
   1943 	addrs = kmem_zalloc(sizeof(*addrs) * multicnt, KM_SLEEP);
   1944 
   1945 	ETHER_LOCK(ec);
   1946 	if (multicnt != ec->ec_multicnt) {
   1947 		/* The number of multicast addresses has changed */
   1948 		ETHER_UNLOCK(ec);
   1949 		kmem_free(addrs, sizeof(*addrs) * multicnt);
   1950 		goto retry;
   1951 	}
   1952 
   1953 	i = 0;
   1954 	LIST_FOREACH(enm, &ec->ec_multiaddrs, enm_list) {
   1955 		struct ether_multi_sysctl *addr = &addrs[i];
   1956 		addr->enm_refcount = enm->enm_refcount;
   1957 		memcpy(addr->enm_addrlo, enm->enm_addrlo, ETHER_ADDR_LEN);
   1958 		memcpy(addr->enm_addrhi, enm->enm_addrhi, ETHER_ADDR_LEN);
   1959 		i++;
   1960 	}
   1961 	ETHER_UNLOCK(ec);
   1962 
   1963 	error = 0;
   1964 	written = 0;
   1965 	for (i = 0; i < multicnt; i++) {
   1966 		struct ether_multi_sysctl *addr = &addrs[i];
   1967 
   1968 		if (written + sizeof(*addr) > *oldlenp)
   1969 			break;
   1970 		error = sysctl_copyout(l, addr, oldp, sizeof(*addr));
   1971 		if (error)
   1972 			break;
   1973 		written += sizeof(*addr);
   1974 		oldp = (char *)oldp + sizeof(*addr);
   1975 	}
   1976 	kmem_free(addrs, sizeof(*addrs) * multicnt);
   1977 
   1978 	if_put(ifp, &psref);
   1979 
   1980 	*oldlenp = written;
   1981 out:
   1982 	curlwp_bindx(bound);
   1983 	return error;
   1984 }
   1985 
   1986 static void
   1987 ether_sysctl_setup(struct sysctllog **clog)
   1988 {
   1989 	const struct sysctlnode *rnode = NULL;
   1990 
   1991 	sysctl_createv(clog, 0, NULL, &rnode,
   1992 		       CTLFLAG_PERMANENT,
   1993 		       CTLTYPE_NODE, "ether",
   1994 		       SYSCTL_DESCR("Ethernet-specific information"),
   1995 		       NULL, 0, NULL, 0,
   1996 		       CTL_NET, CTL_CREATE, CTL_EOL);
   1997 
   1998 	sysctl_createv(clog, 0, &rnode, NULL,
   1999 		       CTLFLAG_PERMANENT,
   2000 		       CTLTYPE_NODE, "multicast",
   2001 		       SYSCTL_DESCR("multicast addresses"),
   2002 		       ether_multicast_sysctl, 0, NULL, 0,
   2003 		       CTL_CREATE, CTL_EOL);
   2004 
   2005 	sysctl_createv(clog, 0, &rnode, NULL,
   2006 		       CTLFLAG_PERMANENT | CTLFLAG_READWRITE,
   2007 		       CTLTYPE_STRING, "rps_hash",
   2008 		       SYSCTL_DESCR("Interface rps hash function control"),
   2009 		       sysctl_pktq_rps_hash_handler, 0, (void *)&ether_pktq_rps_hash_p,
   2010 		       PKTQ_RPS_HASH_NAME_LEN,
   2011 		       CTL_CREATE, CTL_EOL);
   2012 }
   2013 
   2014 void
   2015 etherinit(void)
   2016 {
   2017 
   2018 #ifdef DIAGNOSTIC
   2019 	mutex_init(&bigpktpps_lock, MUTEX_DEFAULT, IPL_NET);
   2020 #endif
   2021 	ether_pktq_rps_hash_p = pktq_rps_hash_default;
   2022 	ether_sysctl_setup(NULL);
   2023 }
   2024