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if_ethersubr.c revision 1.170
      1 /*	$NetBSD: if_ethersubr.c,v 1.170 2008/11/07 00:20:13 dyoung 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 1.170 2008/11/07 00:20:13 dyoung Exp $");
     65 
     66 #include "opt_inet.h"
     67 #include "opt_atalk.h"
     68 #include "opt_iso.h"
     69 #include "opt_ipx.h"
     70 #include "opt_mbuftrace.h"
     71 #include "opt_gateway.h"
     72 #include "opt_pfil_hooks.h"
     73 #include "opt_pppoe.h"
     74 #include "vlan.h"
     75 #include "pppoe.h"
     76 #include "bridge.h"
     77 #include "bpfilter.h"
     78 #include "arp.h"
     79 #include "agr.h"
     80 
     81 #include <sys/param.h>
     82 #include <sys/systm.h>
     83 #include <sys/kernel.h>
     84 #include <sys/callout.h>
     85 #include <sys/malloc.h>
     86 #include <sys/mbuf.h>
     87 #include <sys/protosw.h>
     88 #include <sys/socket.h>
     89 #include <sys/ioctl.h>
     90 #include <sys/errno.h>
     91 #include <sys/syslog.h>
     92 #include <sys/kauth.h>
     93 #include <sys/cpu.h>
     94 #include <sys/intr.h>
     95 #include <sys/device.h>
     96 
     97 #include <net/if.h>
     98 #include <net/netisr.h>
     99 #include <net/route.h>
    100 #include <net/if_llc.h>
    101 #include <net/if_dl.h>
    102 #include <net/if_types.h>
    103 
    104 #include <net/if_media.h>
    105 #include <dev/mii/mii.h>
    106 #include <dev/mii/miivar.h>
    107 
    108 #if NARP == 0
    109 /*
    110  * XXX there should really be a way to issue this warning from within config(8)
    111  */
    112 #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.
    113 #endif
    114 
    115 #if NBPFILTER > 0
    116 #include <net/bpf.h>
    117 #endif
    118 
    119 #include <net/if_ether.h>
    120 #if NVLAN > 0
    121 #include <net/if_vlanvar.h>
    122 #endif
    123 
    124 #if NPPPOE > 0
    125 #include <net/if_pppoe.h>
    126 #endif
    127 
    128 #if NAGR > 0
    129 #include <net/agr/ieee8023_slowprotocols.h>	/* XXX */
    130 #include <net/agr/ieee8023ad.h>
    131 #include <net/agr/if_agrvar.h>
    132 #endif
    133 
    134 #if NBRIDGE > 0
    135 #include <net/if_bridgevar.h>
    136 #endif
    137 
    138 #include <netinet/in.h>
    139 #ifdef INET
    140 #include <netinet/in_var.h>
    141 #endif
    142 #include <netinet/if_inarp.h>
    143 
    144 #ifdef INET6
    145 #ifndef INET
    146 #include <netinet/in.h>
    147 #endif
    148 #include <netinet6/in6_var.h>
    149 #include <netinet6/nd6.h>
    150 #endif
    151 
    152 
    153 #include "carp.h"
    154 #if NCARP > 0
    155 #include <netinet/ip_carp.h>
    156 #endif
    157 
    158 #ifdef IPX
    159 #include <netipx/ipx.h>
    160 #include <netipx/ipx_if.h>
    161 #endif
    162 
    163 #ifdef ISO
    164 #include <netiso/argo_debug.h>
    165 #include <netiso/iso.h>
    166 #include <netiso/iso_var.h>
    167 #include <netiso/iso_snpac.h>
    168 #endif
    169 
    170 
    171 
    172 #ifdef NETATALK
    173 #include <netatalk/at.h>
    174 #include <netatalk/at_var.h>
    175 #include <netatalk/at_extern.h>
    176 
    177 #define llc_snap_org_code llc_un.type_snap.org_code
    178 #define llc_snap_ether_type llc_un.type_snap.ether_type
    179 
    180 extern u_char	at_org_code[3];
    181 extern u_char	aarp_org_code[3];
    182 #endif /* NETATALK */
    183 
    184 static struct timeval bigpktppslim_last;
    185 static int bigpktppslim = 2;	/* XXX */
    186 static int bigpktpps_count;
    187 
    188 
    189 const uint8_t etherbroadcastaddr[ETHER_ADDR_LEN] =
    190     { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff };
    191 const uint8_t ethermulticastaddr_slowprotocols[ETHER_ADDR_LEN] =
    192     { 0x01, 0x80, 0xc2, 0x00, 0x00, 0x02 };
    193 #define senderr(e) { error = (e); goto bad;}
    194 
    195 static	int ether_output(struct ifnet *, struct mbuf *,
    196 	    const struct sockaddr *, struct rtentry *);
    197 
    198 /*
    199  * Ethernet output routine.
    200  * Encapsulate a packet of type family for the local net.
    201  * Assumes that ifp is actually pointer to ethercom structure.
    202  */
    203 static int
    204 ether_output(struct ifnet *ifp0, struct mbuf *m0, const struct sockaddr *dst,
    205 	struct rtentry *rt0)
    206 {
    207 	uint16_t etype = 0;
    208 	int error = 0, hdrcmplt = 0;
    209  	uint8_t esrc[6], edst[6];
    210 	struct mbuf *m = m0;
    211 	struct rtentry *rt;
    212 	struct mbuf *mcopy = NULL;
    213 	struct ether_header *eh;
    214 	struct ifnet *ifp = ifp0;
    215 	ALTQ_DECL(struct altq_pktattr pktattr;)
    216 #ifdef INET
    217 	struct arphdr *ah;
    218 #endif /* INET */
    219 #ifdef NETATALK
    220 	struct at_ifaddr *aa;
    221 #endif /* NETATALK */
    222 
    223 #ifdef MBUFTRACE
    224 	m_claimm(m, ifp->if_mowner);
    225 #endif
    226 
    227 #if NCARP > 0
    228 	if (ifp->if_type == IFT_CARP) {
    229 		struct ifaddr *ifa;
    230 
    231 		/* loop back if this is going to the carp interface */
    232 		if (dst != NULL && ifp0->if_link_state == LINK_STATE_UP &&
    233 		    (ifa = ifa_ifwithaddr(dst)) != NULL &&
    234 		    ifa->ifa_ifp == ifp0)
    235 			return looutput(ifp0, m, dst, rt0);
    236 
    237 		ifp = ifp->if_carpdev;
    238 		/* ac = (struct arpcom *)ifp; */
    239 
    240 		if ((ifp0->if_flags & (IFF_UP|IFF_RUNNING)) !=
    241 		    (IFF_UP|IFF_RUNNING))
    242 			senderr(ENETDOWN);
    243 	}
    244 #endif /* NCARP > 0 */
    245 
    246 	if ((ifp->if_flags & (IFF_UP|IFF_RUNNING)) != (IFF_UP|IFF_RUNNING))
    247 		senderr(ENETDOWN);
    248 	if ((rt = rt0) != NULL) {
    249 		if ((rt->rt_flags & RTF_UP) == 0) {
    250 			if ((rt0 = rt = rtalloc1(dst, 1)) != NULL) {
    251 				rt->rt_refcnt--;
    252 				if (rt->rt_ifp != ifp)
    253 					return (*rt->rt_ifp->if_output)
    254 							(ifp, m0, dst, rt);
    255 			} else
    256 				senderr(EHOSTUNREACH);
    257 		}
    258 		if ((rt->rt_flags & RTF_GATEWAY) && dst->sa_family != AF_NS) {
    259 			if (rt->rt_gwroute == NULL)
    260 				goto lookup;
    261 			if (((rt = rt->rt_gwroute)->rt_flags & RTF_UP) == 0) {
    262 				rtfree(rt); rt = rt0;
    263 			lookup: rt->rt_gwroute = rtalloc1(rt->rt_gateway, 1);
    264 				if ((rt = rt->rt_gwroute) == NULL)
    265 					senderr(EHOSTUNREACH);
    266 				/* the "G" test below also prevents rt == rt0 */
    267 				if ((rt->rt_flags & RTF_GATEWAY) ||
    268 				    (rt->rt_ifp != ifp)) {
    269 					rt->rt_refcnt--;
    270 					rt0->rt_gwroute = NULL;
    271 					senderr(EHOSTUNREACH);
    272 				}
    273 			}
    274 		}
    275 		if (rt->rt_flags & RTF_REJECT)
    276 			if (rt->rt_rmx.rmx_expire == 0 ||
    277 			    (u_long) time_second < rt->rt_rmx.rmx_expire)
    278 				senderr(rt == rt0 ? EHOSTDOWN : EHOSTUNREACH);
    279 	}
    280 
    281 	switch (dst->sa_family) {
    282 
    283 #ifdef INET
    284 	case AF_INET:
    285 		if (m->m_flags & M_BCAST)
    286                 	(void)memcpy(edst, etherbroadcastaddr, sizeof(edst));
    287 		else if (m->m_flags & M_MCAST)
    288 			ETHER_MAP_IP_MULTICAST(&satocsin(dst)->sin_addr, edst);
    289 		else if (!arpresolve(ifp, rt, m, dst, edst))
    290 			return (0);	/* if not yet resolved */
    291 		/* If broadcasting on a simplex interface, loopback a copy */
    292 		if ((m->m_flags & M_BCAST) && (ifp->if_flags & IFF_SIMPLEX))
    293 			mcopy = m_copy(m, 0, (int)M_COPYALL);
    294 		etype = htons(ETHERTYPE_IP);
    295 		break;
    296 
    297 	case AF_ARP:
    298 		ah = mtod(m, struct arphdr *);
    299 		if (m->m_flags & M_BCAST)
    300                 	(void)memcpy(edst, etherbroadcastaddr, sizeof(edst));
    301 		else {
    302 			void *tha = ar_tha(ah);
    303 
    304 			KASSERT(tha);
    305 			memcpy(edst, tha, sizeof(edst));
    306 		}
    307 
    308 		ah->ar_hrd = htons(ARPHRD_ETHER);
    309 
    310 		switch (ntohs(ah->ar_op)) {
    311 		case ARPOP_REVREQUEST:
    312 		case ARPOP_REVREPLY:
    313 			etype = htons(ETHERTYPE_REVARP);
    314 			break;
    315 
    316 		case ARPOP_REQUEST:
    317 		case ARPOP_REPLY:
    318 		default:
    319 			etype = htons(ETHERTYPE_ARP);
    320 		}
    321 
    322 		break;
    323 #endif
    324 #ifdef INET6
    325 	case AF_INET6:
    326 		if (!nd6_storelladdr(ifp, rt, m, dst, edst, sizeof(edst))){
    327 			/* something bad happened */
    328 			return (0);
    329 		}
    330 		etype = htons(ETHERTYPE_IPV6);
    331 		break;
    332 #endif
    333 #ifdef NETATALK
    334     case AF_APPLETALK:
    335 		if (!aarpresolve(ifp, m, (const struct sockaddr_at *)dst, edst)) {
    336 #ifdef NETATALKDEBUG
    337 			printf("aarpresolv failed\n");
    338 #endif /* NETATALKDEBUG */
    339 			return (0);
    340 		}
    341 		/*
    342 		 * ifaddr is the first thing in at_ifaddr
    343 		 */
    344 		aa = (struct at_ifaddr *) at_ifawithnet(
    345 		    (const struct sockaddr_at *)dst, ifp);
    346 		if (aa == NULL)
    347 		    goto bad;
    348 
    349 		/*
    350 		 * In the phase 2 case, we need to prepend an mbuf for the
    351 		 * llc header.  Since we must preserve the value of m,
    352 		 * which is passed to us by value, we m_copy() the first
    353 		 * mbuf, and use it for our llc header.
    354 		 */
    355 		if (aa->aa_flags & AFA_PHASE2) {
    356 			struct llc llc;
    357 
    358 			M_PREPEND(m, sizeof(struct llc), M_DONTWAIT);
    359 			llc.llc_dsap = llc.llc_ssap = LLC_SNAP_LSAP;
    360 			llc.llc_control = LLC_UI;
    361 			memcpy(llc.llc_snap_org_code, at_org_code,
    362 			    sizeof(llc.llc_snap_org_code));
    363 			llc.llc_snap_ether_type = htons(ETHERTYPE_ATALK);
    364 			memcpy(mtod(m, void *), &llc, sizeof(struct llc));
    365 		} else {
    366 			etype = htons(ETHERTYPE_ATALK);
    367 		}
    368 		break;
    369 #endif /* NETATALK */
    370 #ifdef IPX
    371 	case AF_IPX:
    372 		etype = htons(ETHERTYPE_IPX);
    373  		memcpy(edst,
    374 		    &(((const struct sockaddr_ipx *)dst)->sipx_addr.x_host),
    375 		    sizeof(edst));
    376 		/* If broadcasting on a simplex interface, loopback a copy */
    377 		if ((m->m_flags & M_BCAST) && (ifp->if_flags & IFF_SIMPLEX))
    378 			mcopy = m_copy(m, 0, (int)M_COPYALL);
    379 		break;
    380 #endif
    381 #ifdef	ISO
    382 	case AF_ISO: {
    383 		int	snpalen;
    384 		struct	llc *l;
    385 		const struct sockaddr_dl *sdl;
    386 
    387 		if (rt && (sdl = satocsdl(rt->rt_gateway)) &&
    388 		    sdl->sdl_family == AF_LINK && sdl->sdl_alen > 0) {
    389 			memcpy(edst, CLLADDR(sdl), sizeof(edst));
    390 		} else {
    391 			error = iso_snparesolve(ifp,
    392 			    (const struct sockaddr_iso *)dst,
    393 						(char *)edst, &snpalen);
    394 			if (error)
    395 				goto bad; /* Not Resolved */
    396 		}
    397 		/* If broadcasting on a simplex interface, loopback a copy */
    398 		if (*edst & 1)
    399 			m->m_flags |= (M_BCAST|M_MCAST);
    400 		if ((m->m_flags & M_BCAST) && (ifp->if_flags & IFF_SIMPLEX) &&
    401 		    (mcopy = m_copy(m, 0, (int)M_COPYALL))) {
    402 			M_PREPEND(mcopy, sizeof (*eh), M_DONTWAIT);
    403 			if (mcopy) {
    404 				eh = mtod(mcopy, struct ether_header *);
    405 				memcpy(eh->ether_dhost, edst, sizeof(edst));
    406 				memcpy(eh->ether_shost, CLLADDR(ifp->if_sadl),
    407 				    sizeof(edst));
    408 			}
    409 		}
    410 		M_PREPEND(m, 3, M_DONTWAIT);
    411 		if (m == NULL)
    412 			return (0);
    413 		l = mtod(m, struct llc *);
    414 		l->llc_dsap = l->llc_ssap = LLC_ISO_LSAP;
    415 		l->llc_control = LLC_UI;
    416 #ifdef ARGO_DEBUG
    417 		if (argo_debug[D_ETHER]) {
    418 			int i;
    419 			printf("unoutput: sending pkt to: ");
    420 			for (i=0; i<6; i++)
    421 				printf("%x ", edst[i] & 0xff);
    422 			printf("\n");
    423 		}
    424 #endif
    425 		} break;
    426 #endif /* ISO */
    427 
    428 	case pseudo_AF_HDRCMPLT:
    429 		hdrcmplt = 1;
    430 		memcpy(esrc,
    431 		    ((const struct ether_header *)dst->sa_data)->ether_shost,
    432 		    sizeof(esrc));
    433 		/* FALLTHROUGH */
    434 
    435 	case AF_UNSPEC:
    436  		memcpy(edst,
    437 		    ((const struct ether_header *)dst->sa_data)->ether_dhost,
    438 		    sizeof(edst));
    439 		/* AF_UNSPEC doesn't swap the byte order of the ether_type. */
    440 		etype = ((const struct ether_header *)dst->sa_data)->ether_type;
    441 		break;
    442 
    443 	default:
    444 		printf("%s: can't handle af%d\n", ifp->if_xname,
    445 			dst->sa_family);
    446 		senderr(EAFNOSUPPORT);
    447 	}
    448 
    449 	if (mcopy)
    450 		(void)looutput(ifp, mcopy, dst, rt);
    451 
    452 	/* If no ether type is set, this must be a 802.2 formatted packet.
    453 	 */
    454 	if (etype == 0)
    455 		etype = htons(m->m_pkthdr.len);
    456 	/*
    457 	 * Add local net header.  If no space in first mbuf,
    458 	 * allocate another.
    459 	 */
    460 	M_PREPEND(m, sizeof (struct ether_header), M_DONTWAIT);
    461 	if (m == 0)
    462 		senderr(ENOBUFS);
    463 	eh = mtod(m, struct ether_header *);
    464 	/* Note: etype is already in network byte order. */
    465 	(void)memcpy(&eh->ether_type, &etype, sizeof(eh->ether_type));
    466  	memcpy(eh->ether_dhost, edst, sizeof(edst));
    467 	if (hdrcmplt)
    468 		memcpy(eh->ether_shost, esrc, sizeof(eh->ether_shost));
    469 	else
    470 	 	memcpy(eh->ether_shost, CLLADDR(ifp->if_sadl),
    471 		    sizeof(eh->ether_shost));
    472 
    473 #if NCARP > 0
    474 	if (ifp0 != ifp && ifp0->if_type == IFT_CARP) {
    475 	 	memcpy(eh->ether_shost, CLLADDR(ifp0->if_sadl),
    476 		    sizeof(eh->ether_shost));
    477 	}
    478 #endif /* NCARP > 0 */
    479 
    480 #ifdef PFIL_HOOKS
    481 	if ((error = pfil_run_hooks(&ifp->if_pfil, &m, ifp, PFIL_OUT)) != 0)
    482 		return (error);
    483 	if (m == NULL)
    484 		return (0);
    485 #endif
    486 
    487 #if NBRIDGE > 0
    488 	/*
    489 	 * Bridges require special output handling.
    490 	 */
    491 	if (ifp->if_bridge)
    492 		return (bridge_output(ifp, m, NULL, NULL));
    493 #endif
    494 
    495 #if NCARP > 0
    496 	if (ifp != ifp0)
    497 		ifp0->if_obytes += m->m_pkthdr.len + ETHER_HDR_LEN;
    498 #endif /* NCARP > 0 */
    499 
    500 #ifdef ALTQ
    501 	/*
    502 	 * If ALTQ is enabled on the parent interface, do
    503 	 * classification; the queueing discipline might not
    504 	 * require classification, but might require the
    505 	 * address family/header pointer in the pktattr.
    506 	 */
    507 	if (ALTQ_IS_ENABLED(&ifp->if_snd))
    508 		altq_etherclassify(&ifp->if_snd, m, &pktattr);
    509 #endif
    510 
    511 	return ifq_enqueue(ifp, m ALTQ_COMMA ALTQ_DECL(&pktattr));
    512 
    513 bad:
    514 	if (m)
    515 		m_freem(m);
    516 	return (error);
    517 }
    518 
    519 #ifdef ALTQ
    520 /*
    521  * This routine is a slight hack to allow a packet to be classified
    522  * if the Ethernet headers are present.  It will go away when ALTQ's
    523  * classification engine understands link headers.
    524  */
    525 void
    526 altq_etherclassify(struct ifaltq *ifq, struct mbuf *m,
    527     struct altq_pktattr *pktattr)
    528 {
    529 	struct ether_header *eh;
    530 	uint16_t ether_type;
    531 	int hlen, af, hdrsize;
    532 	void *hdr;
    533 
    534 	hlen = ETHER_HDR_LEN;
    535 	eh = mtod(m, struct ether_header *);
    536 
    537 	ether_type = htons(eh->ether_type);
    538 
    539 	if (ether_type < ETHERMTU) {
    540 		/* LLC/SNAP */
    541 		struct llc *llc = (struct llc *)(eh + 1);
    542 		hlen += 8;
    543 
    544 		if (m->m_len < hlen ||
    545 		    llc->llc_dsap != LLC_SNAP_LSAP ||
    546 		    llc->llc_ssap != LLC_SNAP_LSAP ||
    547 		    llc->llc_control != LLC_UI) {
    548 			/* Not SNAP. */
    549 			goto bad;
    550 		}
    551 
    552 		ether_type = htons(llc->llc_un.type_snap.ether_type);
    553 	}
    554 
    555 	switch (ether_type) {
    556 	case ETHERTYPE_IP:
    557 		af = AF_INET;
    558 		hdrsize = 20;		/* sizeof(struct ip) */
    559 		break;
    560 
    561 	case ETHERTYPE_IPV6:
    562 		af = AF_INET6;
    563 		hdrsize = 40;		/* sizeof(struct ip6_hdr) */
    564 		break;
    565 
    566 	default:
    567 		af = AF_UNSPEC;
    568 		hdrsize = 0;
    569 		break;
    570 	}
    571 
    572 	while (m->m_len <= hlen) {
    573 		hlen -= m->m_len;
    574 		m = m->m_next;
    575 	}
    576 	if (m->m_len < (hlen + hdrsize)) {
    577 		/*
    578 		 * protocol header not in a single mbuf.
    579 		 * We can't cope with this situation right
    580 		 * now (but it shouldn't ever happen, really, anyhow).
    581 		 */
    582 #ifdef DEBUG
    583 		printf("altq_etherclassify: headers span multiple mbufs: "
    584 		    "%d < %d\n", m->m_len, (hlen + hdrsize));
    585 #endif
    586 		goto bad;
    587 	}
    588 
    589 	m->m_data += hlen;
    590 	m->m_len -= hlen;
    591 
    592 	hdr = mtod(m, void *);
    593 
    594 	if (ALTQ_NEEDS_CLASSIFY(ifq))
    595 		pktattr->pattr_class =
    596 		    (*ifq->altq_classify)(ifq->altq_clfier, m, af);
    597 	pktattr->pattr_af = af;
    598 	pktattr->pattr_hdr = hdr;
    599 
    600 	m->m_data -= hlen;
    601 	m->m_len += hlen;
    602 
    603 	return;
    604 
    605  bad:
    606 	pktattr->pattr_class = NULL;
    607 	pktattr->pattr_hdr = NULL;
    608 	pktattr->pattr_af = AF_UNSPEC;
    609 }
    610 #endif /* ALTQ */
    611 
    612 /*
    613  * Process a received Ethernet packet;
    614  * the packet is in the mbuf chain m with
    615  * the ether header.
    616  */
    617 void
    618 ether_input(struct ifnet *ifp, struct mbuf *m)
    619 {
    620 	struct ethercom *ec = (struct ethercom *) ifp;
    621 	struct ifqueue *inq;
    622 	uint16_t etype;
    623 	struct ether_header *eh;
    624 #if defined (ISO) || defined (LLC) || defined(NETATALK)
    625 	struct llc *l;
    626 #endif
    627 
    628 	if ((ifp->if_flags & IFF_UP) == 0) {
    629 		m_freem(m);
    630 		return;
    631 	}
    632 
    633 #ifdef MBUFTRACE
    634 	m_claimm(m, &ec->ec_rx_mowner);
    635 #endif
    636 	eh = mtod(m, struct ether_header *);
    637 	etype = ntohs(eh->ether_type);
    638 
    639 	/*
    640 	 * Determine if the packet is within its size limits.
    641 	 */
    642 	if (m->m_pkthdr.len >
    643 	    ETHER_MAX_FRAME(ifp, etype, m->m_flags & M_HASFCS)) {
    644 		if (ppsratecheck(&bigpktppslim_last, &bigpktpps_count,
    645 			    bigpktppslim)) {
    646 			printf("%s: discarding oversize frame (len=%d)\n",
    647 			    ifp->if_xname, m->m_pkthdr.len);
    648 		}
    649 		m_freem(m);
    650 		return;
    651 	}
    652 
    653 	if (ETHER_IS_MULTICAST(eh->ether_dhost)) {
    654 		/*
    655 		 * If this is not a simplex interface, drop the packet
    656 		 * if it came from us.
    657 		 */
    658 		if ((ifp->if_flags & IFF_SIMPLEX) == 0 &&
    659 		    memcmp(CLLADDR(ifp->if_sadl), eh->ether_shost,
    660 		    ETHER_ADDR_LEN) == 0) {
    661 			m_freem(m);
    662 			return;
    663 		}
    664 
    665 		if (memcmp(etherbroadcastaddr,
    666 		    eh->ether_dhost, ETHER_ADDR_LEN) == 0)
    667 			m->m_flags |= M_BCAST;
    668 		else
    669 			m->m_flags |= M_MCAST;
    670 		ifp->if_imcasts++;
    671 	}
    672 
    673 	/* If the CRC is still on the packet, trim it off. */
    674 	if (m->m_flags & M_HASFCS) {
    675 		m_adj(m, -ETHER_CRC_LEN);
    676 		m->m_flags &= ~M_HASFCS;
    677 	}
    678 
    679 	ifp->if_ibytes += m->m_pkthdr.len;
    680 
    681 #if NBRIDGE > 0
    682 	/*
    683 	 * Tap the packet off here for a bridge.  bridge_input()
    684 	 * will return NULL if it has consumed the packet, otherwise
    685 	 * it gets processed as normal.  Note that bridge_input()
    686 	 * will always return the original packet if we need to
    687 	 * process it locally.
    688 	 */
    689 	if (ifp->if_bridge) {
    690 		/* clear M_PROMISC, in case the packets comes from a vlan */
    691 		m->m_flags &= ~M_PROMISC;
    692 		m = bridge_input(ifp, m);
    693 		if (m == NULL)
    694 			return;
    695 
    696 		/*
    697 		 * Bridge has determined that the packet is for us.
    698 		 * Update our interface pointer -- we may have had
    699 		 * to "bridge" the packet locally.
    700 		 */
    701 		ifp = m->m_pkthdr.rcvif;
    702 	} else
    703 #endif /* NBRIDGE > 0 */
    704 	{
    705 
    706 #if NCARP > 0
    707 		if (__predict_false(ifp->if_carp && ifp->if_type != IFT_CARP)) {
    708 			/*
    709 			 * clear M_PROMISC, in case the packets comes from a
    710 			 * vlan
    711 			 */
    712 			m->m_flags &= ~M_PROMISC;
    713 			if (carp_input(m, (uint8_t *)&eh->ether_shost,
    714 			    (uint8_t *)&eh->ether_dhost, eh->ether_type) == 0)
    715 				return;
    716 		}
    717 #endif /* NCARP > 0 */
    718 		if ((m->m_flags & (M_BCAST|M_MCAST|M_PROMISC)) == 0 &&
    719 		    (ifp->if_flags & IFF_PROMISC) != 0 &&
    720 		    memcmp(CLLADDR(ifp->if_sadl), eh->ether_dhost,
    721 			   ETHER_ADDR_LEN) != 0) {
    722 			m->m_flags |= M_PROMISC;
    723 		}
    724 	}
    725 
    726 #ifdef PFIL_HOOKS
    727 	if ((m->m_flags & M_PROMISC) == 0) {
    728 		if (pfil_run_hooks(&ifp->if_pfil, &m, ifp, PFIL_IN) != 0)
    729 			return;
    730 		if (m == NULL)
    731 			return;
    732 
    733 		eh = mtod(m, struct ether_header *);
    734 		etype = ntohs(eh->ether_type);
    735 	}
    736 #endif
    737 
    738 	/*
    739 	 * If VLANs are configured on the interface, check to
    740 	 * see if the device performed the decapsulation and
    741 	 * provided us with the tag.
    742 	 */
    743 	if (ec->ec_nvlans && m_tag_find(m, PACKET_TAG_VLAN, NULL) != NULL) {
    744 #if NVLAN > 0
    745 		/*
    746 		 * vlan_input() will either recursively call ether_input()
    747 		 * or drop the packet.
    748 		 */
    749 		vlan_input(ifp, m);
    750 #else
    751 		m_freem(m);
    752 #endif
    753 		return;
    754 	}
    755 
    756 #if NAGR > 0
    757 	if (ifp->if_agrprivate &&
    758 	    __predict_true(etype != ETHERTYPE_SLOWPROTOCOLS)) {
    759 		m->m_flags &= ~M_PROMISC;
    760 		agr_input(ifp, m);
    761 		return;
    762 	}
    763 #endif /* NAGR > 0 */
    764 
    765 	/*
    766 	 * Handle protocols that expect to have the Ethernet header
    767 	 * (and possibly FCS) intact.
    768 	 */
    769 	switch (etype) {
    770 #if NVLAN > 0
    771 	case ETHERTYPE_VLAN:
    772 		/*
    773 		 * vlan_input() will either recursively call ether_input()
    774 		 * or drop the packet.
    775 		 */
    776 		if (((struct ethercom *)ifp)->ec_nvlans != 0)
    777 			vlan_input(ifp, m);
    778 		else
    779 			m_freem(m);
    780 		return;
    781 #endif /* NVLAN > 0 */
    782 #if NPPPOE > 0
    783 	case ETHERTYPE_PPPOEDISC:
    784 	case ETHERTYPE_PPPOE:
    785 		if (m->m_flags & M_PROMISC) {
    786 			m_freem(m);
    787 			return;
    788 		}
    789 #ifndef PPPOE_SERVER
    790 		if (m->m_flags & (M_MCAST | M_BCAST)) {
    791 			m_freem(m);
    792 			return;
    793 		}
    794 #endif
    795 
    796 		if (etype == ETHERTYPE_PPPOEDISC)
    797 			inq = &ppoediscinq;
    798 		else
    799 			inq = &ppoeinq;
    800 		if (IF_QFULL(inq)) {
    801 			IF_DROP(inq);
    802 			m_freem(m);
    803 		} else
    804 			IF_ENQUEUE(inq, m);
    805 		softint_schedule(pppoe_softintr);
    806 		return;
    807 #endif /* NPPPOE > 0 */
    808 	case ETHERTYPE_SLOWPROTOCOLS: {
    809 		uint8_t subtype;
    810 
    811 #if defined(DIAGNOSTIC)
    812 		if (m->m_pkthdr.len < sizeof(*eh) + sizeof(subtype)) {
    813 			panic("ether_input: too short slow protocol packet");
    814 		}
    815 #endif
    816 		m_copydata(m, sizeof(*eh), sizeof(subtype), &subtype);
    817 		switch (subtype) {
    818 #if NAGR > 0
    819 		case SLOWPROTOCOLS_SUBTYPE_LACP:
    820 			if (ifp->if_agrprivate) {
    821 				ieee8023ad_lacp_input(ifp, m);
    822 				return;
    823 			}
    824 			break;
    825 
    826 		case SLOWPROTOCOLS_SUBTYPE_MARKER:
    827 			if (ifp->if_agrprivate) {
    828 				ieee8023ad_marker_input(ifp, m);
    829 				return;
    830 			}
    831 			break;
    832 #endif /* NAGR > 0 */
    833 		default:
    834 			if (subtype == 0 || subtype > 10) {
    835 				/* illegal value */
    836 				m_freem(m);
    837 				return;
    838 			}
    839 			/* unknown subtype */
    840 			break;
    841 		}
    842 		/* FALLTHROUGH */
    843 	}
    844 	default:
    845 		if (m->m_flags & M_PROMISC) {
    846 			m_freem(m);
    847 			return;
    848 		}
    849 	}
    850 
    851 	/* If the CRC is still on the packet, trim it off. */
    852 	if (m->m_flags & M_HASFCS) {
    853 		m_adj(m, -ETHER_CRC_LEN);
    854 		m->m_flags &= ~M_HASFCS;
    855 	}
    856 
    857 	if (etype > ETHERMTU + sizeof (struct ether_header)) {
    858 		/* Strip off the Ethernet header. */
    859 		m_adj(m, sizeof(struct ether_header));
    860 
    861 		switch (etype) {
    862 #ifdef INET
    863 		case ETHERTYPE_IP:
    864 #ifdef GATEWAY
    865 			if (ipflow_fastforward(m))
    866 				return;
    867 #endif
    868 			schednetisr(NETISR_IP);
    869 			inq = &ipintrq;
    870 			break;
    871 
    872 		case ETHERTYPE_ARP:
    873 			schednetisr(NETISR_ARP);
    874 			inq = &arpintrq;
    875 			break;
    876 
    877 		case ETHERTYPE_REVARP:
    878 			revarpinput(m);	/* XXX queue? */
    879 			return;
    880 #endif
    881 #ifdef INET6
    882 		case ETHERTYPE_IPV6:
    883 #ifdef GATEWAY
    884 			if (ip6flow_fastforward(m))
    885 				return;
    886 #endif
    887 			schednetisr(NETISR_IPV6);
    888 			inq = &ip6intrq;
    889 			break;
    890 #endif
    891 #ifdef IPX
    892 		case ETHERTYPE_IPX:
    893 			schednetisr(NETISR_IPX);
    894 			inq = &ipxintrq;
    895 			break;
    896 #endif
    897 #ifdef NETATALK
    898         	case ETHERTYPE_ATALK:
    899                 	schednetisr(NETISR_ATALK);
    900                 	inq = &atintrq1;
    901                 	break;
    902         	case ETHERTYPE_AARP:
    903 			/* probably this should be done with a NETISR as well */
    904                 	aarpinput(ifp, m); /* XXX */
    905                 	return;
    906 #endif /* NETATALK */
    907 		default:
    908 			m_freem(m);
    909 			return;
    910 		}
    911 	} else {
    912 #if defined (ISO) || defined (LLC) || defined (NETATALK)
    913 		l = (struct llc *)(eh+1);
    914 		switch (l->llc_dsap) {
    915 #ifdef NETATALK
    916 		case LLC_SNAP_LSAP:
    917 			switch (l->llc_control) {
    918 			case LLC_UI:
    919 				if (l->llc_ssap != LLC_SNAP_LSAP) {
    920 					goto dropanyway;
    921 				}
    922 
    923 				if (memcmp(&(l->llc_snap_org_code)[0],
    924 				    at_org_code, sizeof(at_org_code)) == 0 &&
    925 				    ntohs(l->llc_snap_ether_type) ==
    926 				    ETHERTYPE_ATALK) {
    927 					inq = &atintrq2;
    928 					m_adj(m, sizeof(struct ether_header)
    929 					    + sizeof(struct llc));
    930 					schednetisr(NETISR_ATALK);
    931 					break;
    932 				}
    933 
    934 				if (memcmp(&(l->llc_snap_org_code)[0],
    935 				    aarp_org_code,
    936 				    sizeof(aarp_org_code)) == 0 &&
    937 				    ntohs(l->llc_snap_ether_type) ==
    938 				    ETHERTYPE_AARP) {
    939 					m_adj( m, sizeof(struct ether_header)
    940 					    + sizeof(struct llc));
    941 					aarpinput(ifp, m); /* XXX */
    942 				    return;
    943 				}
    944 
    945 			default:
    946 				goto dropanyway;
    947 			}
    948 			break;
    949 #endif /* NETATALK */
    950 #ifdef	ISO
    951 		case LLC_ISO_LSAP:
    952 			switch (l->llc_control) {
    953 			case LLC_UI:
    954 				/* LLC_UI_P forbidden in class 1 service */
    955 				if ((l->llc_dsap == LLC_ISO_LSAP) &&	/* XXX? case tested */
    956 				    (l->llc_ssap == LLC_ISO_LSAP)) {
    957 					/* LSAP for ISO */
    958 					/* XXX length computation?? */
    959 					if (m->m_pkthdr.len > etype + sizeof(struct ether_header))
    960 						m_adj(m, etype - m->m_pkthdr.len);
    961 
    962 #ifdef ARGO_DEBUG
    963 					if (argo_debug[D_ETHER])
    964 						printf("clnp packet");
    965 #endif
    966 					schednetisr(NETISR_ISO);
    967 					inq = &clnlintrq;
    968 					break;
    969 				}
    970 				goto dropanyway;
    971 
    972 			case LLC_XID:
    973 			case LLC_XID_P:
    974 				if(m->m_len < LLC_XID_BASIC_MINLEN + sizeof(struct ether_header))
    975 					/* XXX m_pullup? */
    976 					goto dropanyway;
    977 				l->llc_window = 0;
    978 				l->llc_fid = LLC_XID_FORMAT_BASIC;
    979 				l->llc_class = LLC_XID_CLASS_I;
    980 				l->llc_dsap = l->llc_ssap = 0;
    981 				/* Fall through to */
    982 			case LLC_TEST:
    983 			case LLC_TEST_P:
    984 			{
    985 				struct sockaddr sa;
    986 				struct ether_header *eh2;
    987 				int i;
    988 				u_char c = l->llc_dsap;
    989 
    990 				l->llc_dsap = l->llc_ssap;
    991 				l->llc_ssap = c;
    992 				m_adj(m, sizeof(struct ether_header));
    993 				/* XXX we can optimize here? */
    994 				if (m->m_flags & (M_BCAST | M_MCAST))
    995 					memcpy(eh->ether_dhost,
    996 					    CLLADDR(ifp->if_sadl),
    997 					    ETHER_ADDR_LEN);
    998 				sa.sa_family = AF_UNSPEC;
    999 				sa.sa_len = sizeof(sa);
   1000 				eh2 = (struct ether_header *)sa.sa_data;
   1001 				for (i = 0; i < 6; i++) {
   1002 					eh2->ether_shost[i] = c =
   1003 					    eh->ether_dhost[i];
   1004 					eh2->ether_dhost[i] =
   1005 					    eh->ether_dhost[i] =
   1006 					    eh->ether_shost[i];
   1007 					eh->ether_shost[i] = c;
   1008 				}
   1009 				ifp->if_output(ifp, m, &sa, NULL);
   1010 				return;
   1011 			}
   1012 			default:
   1013 				m_freem(m);
   1014 				return;
   1015 			}
   1016 			break;
   1017 #endif /* ISO */
   1018 #if defined (ISO) || defined (NETATALK)
   1019 		dropanyway:
   1020 #endif
   1021 		default:
   1022 			m_freem(m);
   1023 			return;
   1024 		}
   1025 #else /* ISO || LLC || NETATALK*/
   1026 		m_freem(m);
   1027 		return;
   1028 #endif /* ISO || LLC || NETATALK*/
   1029 	}
   1030 
   1031 	if (IF_QFULL(inq)) {
   1032 		IF_DROP(inq);
   1033 		m_freem(m);
   1034 	} else
   1035 		IF_ENQUEUE(inq, m);
   1036 }
   1037 
   1038 /*
   1039  * Convert Ethernet address to printable (loggable) representation.
   1040  */
   1041 char *
   1042 ether_sprintf(const u_char *ap)
   1043 {
   1044 	static char etherbuf[3 * ETHER_ADDR_LEN];
   1045 	return ether_snprintf(etherbuf, sizeof(etherbuf), ap);
   1046 }
   1047 
   1048 char *
   1049 ether_snprintf(char *buf, size_t len, const u_char *ap)
   1050 {
   1051 	char *cp = buf;
   1052 	size_t i;
   1053 
   1054 	for (i = 0; i < len / 3; i++) {
   1055 		*cp++ = hexdigits[*ap >> 4];
   1056 		*cp++ = hexdigits[*ap++ & 0xf];
   1057 		*cp++ = ':';
   1058 	}
   1059 	*--cp = '\0';
   1060 	return buf;
   1061 }
   1062 
   1063 /*
   1064  * Perform common duties while attaching to interface list
   1065  */
   1066 void
   1067 ether_ifattach(struct ifnet *ifp, const uint8_t *lla)
   1068 {
   1069 	struct ethercom *ec = (struct ethercom *)ifp;
   1070 
   1071 	ifp->if_type = IFT_ETHER;
   1072 	ifp->if_hdrlen = ETHER_HDR_LEN;
   1073 	ifp->if_dlt = DLT_EN10MB;
   1074 	ifp->if_mtu = ETHERMTU;
   1075 	ifp->if_output = ether_output;
   1076 	ifp->if_input = ether_input;
   1077 	if (ifp->if_baudrate == 0)
   1078 		ifp->if_baudrate = IF_Mbps(10);		/* just a default */
   1079 
   1080 	if_set_sadl(ifp, lla, ETHER_ADDR_LEN, !ETHER_IS_LOCAL(lla));
   1081 
   1082 	LIST_INIT(&ec->ec_multiaddrs);
   1083 	ifp->if_broadcastaddr = etherbroadcastaddr;
   1084 #if NBPFILTER > 0
   1085 	bpfattach(ifp, DLT_EN10MB, sizeof(struct ether_header));
   1086 #endif
   1087 #ifdef MBUFTRACE
   1088 	strlcpy(ec->ec_tx_mowner.mo_name, ifp->if_xname,
   1089 	    sizeof(ec->ec_tx_mowner.mo_name));
   1090 	strlcpy(ec->ec_tx_mowner.mo_descr, "tx",
   1091 	    sizeof(ec->ec_tx_mowner.mo_descr));
   1092 	strlcpy(ec->ec_rx_mowner.mo_name, ifp->if_xname,
   1093 	    sizeof(ec->ec_rx_mowner.mo_name));
   1094 	strlcpy(ec->ec_rx_mowner.mo_descr, "rx",
   1095 	    sizeof(ec->ec_rx_mowner.mo_descr));
   1096 	MOWNER_ATTACH(&ec->ec_tx_mowner);
   1097 	MOWNER_ATTACH(&ec->ec_rx_mowner);
   1098 	ifp->if_mowner = &ec->ec_tx_mowner;
   1099 #endif
   1100 }
   1101 
   1102 void
   1103 ether_ifdetach(struct ifnet *ifp)
   1104 {
   1105 	struct ethercom *ec = (void *) ifp;
   1106 	struct ether_multi *enm;
   1107 	int s;
   1108 
   1109 #if NBRIDGE > 0
   1110 	if (ifp->if_bridge)
   1111 		bridge_ifdetach(ifp);
   1112 #endif
   1113 
   1114 #if NBPFILTER > 0
   1115 	bpfdetach(ifp);
   1116 #endif
   1117 
   1118 #if NVLAN > 0
   1119 	if (ec->ec_nvlans)
   1120 		vlan_ifdetach(ifp);
   1121 #endif
   1122 
   1123 	s = splnet();
   1124 	while ((enm = LIST_FIRST(&ec->ec_multiaddrs)) != NULL) {
   1125 		LIST_REMOVE(enm, enm_list);
   1126 		free(enm, M_IFMADDR);
   1127 		ec->ec_multicnt--;
   1128 	}
   1129 	splx(s);
   1130 
   1131 #if 0	/* done in if_detach() */
   1132 	if_free_sadl(ifp);
   1133 #endif
   1134 
   1135 	MOWNER_DETACH(&ec->ec_rx_mowner);
   1136 	MOWNER_DETACH(&ec->ec_tx_mowner);
   1137 }
   1138 
   1139 #if 0
   1140 /*
   1141  * This is for reference.  We have a table-driven version
   1142  * of the little-endian crc32 generator, which is faster
   1143  * than the double-loop.
   1144  */
   1145 uint32_t
   1146 ether_crc32_le(const uint8_t *buf, size_t len)
   1147 {
   1148 	uint32_t c, crc, carry;
   1149 	size_t i, j;
   1150 
   1151 	crc = 0xffffffffU;	/* initial value */
   1152 
   1153 	for (i = 0; i < len; i++) {
   1154 		c = buf[i];
   1155 		for (j = 0; j < 8; j++) {
   1156 			carry = ((crc & 0x01) ? 1 : 0) ^ (c & 0x01);
   1157 			crc >>= 1;
   1158 			c >>= 1;
   1159 			if (carry)
   1160 				crc = (crc ^ ETHER_CRC_POLY_LE);
   1161 		}
   1162 	}
   1163 
   1164 	return (crc);
   1165 }
   1166 #else
   1167 uint32_t
   1168 ether_crc32_le(const uint8_t *buf, size_t len)
   1169 {
   1170 	static const uint32_t crctab[] = {
   1171 		0x00000000, 0x1db71064, 0x3b6e20c8, 0x26d930ac,
   1172 		0x76dc4190, 0x6b6b51f4, 0x4db26158, 0x5005713c,
   1173 		0xedb88320, 0xf00f9344, 0xd6d6a3e8, 0xcb61b38c,
   1174 		0x9b64c2b0, 0x86d3d2d4, 0xa00ae278, 0xbdbdf21c
   1175 	};
   1176 	uint32_t crc;
   1177 	size_t i;
   1178 
   1179 	crc = 0xffffffffU;	/* initial value */
   1180 
   1181 	for (i = 0; i < len; i++) {
   1182 		crc ^= buf[i];
   1183 		crc = (crc >> 4) ^ crctab[crc & 0xf];
   1184 		crc = (crc >> 4) ^ crctab[crc & 0xf];
   1185 	}
   1186 
   1187 	return (crc);
   1188 }
   1189 #endif
   1190 
   1191 uint32_t
   1192 ether_crc32_be(const uint8_t *buf, size_t len)
   1193 {
   1194 	uint32_t c, crc, carry;
   1195 	size_t i, j;
   1196 
   1197 	crc = 0xffffffffU;	/* initial value */
   1198 
   1199 	for (i = 0; i < len; i++) {
   1200 		c = buf[i];
   1201 		for (j = 0; j < 8; j++) {
   1202 			carry = ((crc & 0x80000000U) ? 1 : 0) ^ (c & 0x01);
   1203 			crc <<= 1;
   1204 			c >>= 1;
   1205 			if (carry)
   1206 				crc = (crc ^ ETHER_CRC_POLY_BE) | carry;
   1207 		}
   1208 	}
   1209 
   1210 	return (crc);
   1211 }
   1212 
   1213 #ifdef INET
   1214 const uint8_t ether_ipmulticast_min[ETHER_ADDR_LEN] =
   1215     { 0x01, 0x00, 0x5e, 0x00, 0x00, 0x00 };
   1216 const uint8_t ether_ipmulticast_max[ETHER_ADDR_LEN] =
   1217     { 0x01, 0x00, 0x5e, 0x7f, 0xff, 0xff };
   1218 #endif
   1219 #ifdef INET6
   1220 const uint8_t ether_ip6multicast_min[ETHER_ADDR_LEN] =
   1221     { 0x33, 0x33, 0x00, 0x00, 0x00, 0x00 };
   1222 const uint8_t ether_ip6multicast_max[ETHER_ADDR_LEN] =
   1223     { 0x33, 0x33, 0xff, 0xff, 0xff, 0xff };
   1224 #endif
   1225 
   1226 /*
   1227  * ether_aton implementation, not using a static buffer.
   1228  */
   1229 int
   1230 ether_nonstatic_aton(u_char *dest, char *str)
   1231 {
   1232         int i;
   1233         char *cp = str;
   1234         u_char val[6];
   1235 
   1236 #define set_value                       \
   1237         if (*cp > '9' && *cp < 'a')     \
   1238                 *cp -= 'A' - 10;        \
   1239         else if (*cp > '9')             \
   1240                 *cp -= 'a' - 10;        \
   1241         else                            \
   1242                 *cp -= '0'
   1243 
   1244         for (i = 0; i < 6; i++, cp++) {
   1245                 if (!isxdigit(*cp))
   1246                         return (1);
   1247                 set_value;
   1248                 val[i] = *cp++;
   1249                 if (isxdigit(*cp)) {
   1250                         set_value;
   1251                         val[i] *= 16;
   1252                         val[i] += *cp++;
   1253                 }
   1254                 if (*cp == ':' || i == 5)
   1255                         continue;
   1256                 else
   1257                         return 1;
   1258         }
   1259         memcpy(dest, val, 6);
   1260 
   1261         return 0;
   1262 }
   1263 
   1264 
   1265 /*
   1266  * Convert a sockaddr into an Ethernet address or range of Ethernet
   1267  * addresses.
   1268  */
   1269 int
   1270 ether_multiaddr(const struct sockaddr *sa, uint8_t addrlo[ETHER_ADDR_LEN],
   1271     uint8_t addrhi[ETHER_ADDR_LEN])
   1272 {
   1273 #ifdef INET
   1274 	const struct sockaddr_in *sin;
   1275 #endif /* INET */
   1276 #ifdef INET6
   1277 	const struct sockaddr_in6 *sin6;
   1278 #endif /* INET6 */
   1279 
   1280 	switch (sa->sa_family) {
   1281 
   1282 	case AF_UNSPEC:
   1283 		memcpy(addrlo, sa->sa_data, ETHER_ADDR_LEN);
   1284 		memcpy(addrhi, addrlo, ETHER_ADDR_LEN);
   1285 		break;
   1286 
   1287 #ifdef INET
   1288 	case AF_INET:
   1289 		sin = satocsin(sa);
   1290 		if (sin->sin_addr.s_addr == INADDR_ANY) {
   1291 			/*
   1292 			 * An IP address of INADDR_ANY means listen to
   1293 			 * or stop listening to all of the Ethernet
   1294 			 * multicast addresses used for IP.
   1295 			 * (This is for the sake of IP multicast routers.)
   1296 			 */
   1297 			memcpy(addrlo, ether_ipmulticast_min, ETHER_ADDR_LEN);
   1298 			memcpy(addrhi, ether_ipmulticast_max, ETHER_ADDR_LEN);
   1299 		}
   1300 		else {
   1301 			ETHER_MAP_IP_MULTICAST(&sin->sin_addr, addrlo);
   1302 			memcpy(addrhi, addrlo, ETHER_ADDR_LEN);
   1303 		}
   1304 		break;
   1305 #endif
   1306 #ifdef INET6
   1307 	case AF_INET6:
   1308 		sin6 = satocsin6(sa);
   1309 		if (IN6_IS_ADDR_UNSPECIFIED(&sin6->sin6_addr)) {
   1310 			/*
   1311 			 * An IP6 address of 0 means listen to or stop
   1312 			 * listening to all of the Ethernet multicast
   1313 			 * address used for IP6.
   1314 			 * (This is used for multicast routers.)
   1315 			 */
   1316 			memcpy(addrlo, ether_ip6multicast_min, ETHER_ADDR_LEN);
   1317 			memcpy(addrhi, ether_ip6multicast_max, ETHER_ADDR_LEN);
   1318 		} else {
   1319 			ETHER_MAP_IPV6_MULTICAST(&sin6->sin6_addr, addrlo);
   1320 			memcpy(addrhi, addrlo, ETHER_ADDR_LEN);
   1321 		}
   1322 		break;
   1323 #endif
   1324 
   1325 	default:
   1326 		return EAFNOSUPPORT;
   1327 	}
   1328 	return 0;
   1329 }
   1330 
   1331 /*
   1332  * Add an Ethernet multicast address or range of addresses to the list for a
   1333  * given interface.
   1334  */
   1335 int
   1336 ether_addmulti(const struct sockaddr *sa, struct ethercom *ec)
   1337 {
   1338 	struct ether_multi *enm;
   1339 	u_char addrlo[ETHER_ADDR_LEN];
   1340 	u_char addrhi[ETHER_ADDR_LEN];
   1341 	int s = splnet(), error;
   1342 
   1343 	error = ether_multiaddr(sa, addrlo, addrhi);
   1344 	if (error != 0) {
   1345 		splx(s);
   1346 		return error;
   1347 	}
   1348 
   1349 	/*
   1350 	 * Verify that we have valid Ethernet multicast addresses.
   1351 	 */
   1352 	if ((addrlo[0] & 0x01) != 1 || (addrhi[0] & 0x01) != 1) {
   1353 		splx(s);
   1354 		return EINVAL;
   1355 	}
   1356 	/*
   1357 	 * See if the address range is already in the list.
   1358 	 */
   1359 	ETHER_LOOKUP_MULTI(addrlo, addrhi, ec, enm);
   1360 	if (enm != NULL) {
   1361 		/*
   1362 		 * Found it; just increment the reference count.
   1363 		 */
   1364 		++enm->enm_refcount;
   1365 		splx(s);
   1366 		return 0;
   1367 	}
   1368 	/*
   1369 	 * New address or range; malloc a new multicast record
   1370 	 * and link it into the interface's multicast list.
   1371 	 */
   1372 	enm = (struct ether_multi *)malloc(sizeof(*enm), M_IFMADDR, M_NOWAIT);
   1373 	if (enm == NULL) {
   1374 		splx(s);
   1375 		return ENOBUFS;
   1376 	}
   1377 	memcpy(enm->enm_addrlo, addrlo, 6);
   1378 	memcpy(enm->enm_addrhi, addrhi, 6);
   1379 	enm->enm_refcount = 1;
   1380 	LIST_INSERT_HEAD(&ec->ec_multiaddrs, enm, enm_list);
   1381 	ec->ec_multicnt++;
   1382 	splx(s);
   1383 	/*
   1384 	 * Return ENETRESET to inform the driver that the list has changed
   1385 	 * and its reception filter should be adjusted accordingly.
   1386 	 */
   1387 	return ENETRESET;
   1388 }
   1389 
   1390 /*
   1391  * Delete a multicast address record.
   1392  */
   1393 int
   1394 ether_delmulti(const struct sockaddr *sa, struct ethercom *ec)
   1395 {
   1396 	struct ether_multi *enm;
   1397 	u_char addrlo[ETHER_ADDR_LEN];
   1398 	u_char addrhi[ETHER_ADDR_LEN];
   1399 	int s = splnet(), error;
   1400 
   1401 	error = ether_multiaddr(sa, addrlo, addrhi);
   1402 	if (error != 0) {
   1403 		splx(s);
   1404 		return (error);
   1405 	}
   1406 
   1407 	/*
   1408 	 * Look ur the address in our list.
   1409 	 */
   1410 	ETHER_LOOKUP_MULTI(addrlo, addrhi, ec, enm);
   1411 	if (enm == NULL) {
   1412 		splx(s);
   1413 		return (ENXIO);
   1414 	}
   1415 	if (--enm->enm_refcount != 0) {
   1416 		/*
   1417 		 * Still some claims to this record.
   1418 		 */
   1419 		splx(s);
   1420 		return (0);
   1421 	}
   1422 	/*
   1423 	 * No remaining claims to this record; unlink and free it.
   1424 	 */
   1425 	LIST_REMOVE(enm, enm_list);
   1426 	free(enm, M_IFMADDR);
   1427 	ec->ec_multicnt--;
   1428 	splx(s);
   1429 	/*
   1430 	 * Return ENETRESET to inform the driver that the list has changed
   1431 	 * and its reception filter should be adjusted accordingly.
   1432 	 */
   1433 	return (ENETRESET);
   1434 }
   1435 
   1436 void
   1437 ether_set_ifflags_cb(struct ethercom *ec, ether_cb_t cb)
   1438 {
   1439 	ec->ec_ifflags_cb = cb;
   1440 }
   1441 
   1442 /*
   1443  * Common ioctls for Ethernet interfaces.  Note, we must be
   1444  * called at splnet().
   1445  */
   1446 int
   1447 ether_ioctl(struct ifnet *ifp, u_long cmd, void *data)
   1448 {
   1449 	struct ethercom *ec = (void *) ifp;
   1450 	struct ifreq *ifr = (struct ifreq *)data;
   1451 	struct ifaddr *ifa = (struct ifaddr *)data;
   1452 	struct if_laddrreq *iflr = data;
   1453 	const struct sockaddr_dl *sdl;
   1454 	static const uint8_t zero[ETHER_ADDR_LEN];
   1455 	int error;
   1456 
   1457 	switch (cmd) {
   1458 	case SIOCINITIFADDR:
   1459 		if ((ifp->if_flags & (IFF_UP|IFF_RUNNING)) !=
   1460 		    (IFF_UP|IFF_RUNNING)) {
   1461 			ifp->if_flags |= IFF_UP;
   1462 			if ((error = (*ifp->if_init)(ifp)) != 0)
   1463 				return error;
   1464 		}
   1465 #ifdef INET
   1466 		if (ifa->ifa_addr->sa_family == AF_INET)
   1467 			arp_ifinit(ifp, ifa);
   1468 #endif /* INET */
   1469 		return 0;
   1470 
   1471 	case SIOCSIFMTU:
   1472 	    {
   1473 		int maxmtu;
   1474 
   1475 		if (ec->ec_capabilities & ETHERCAP_JUMBO_MTU)
   1476 			maxmtu = ETHERMTU_JUMBO;
   1477 		else
   1478 			maxmtu = ETHERMTU;
   1479 
   1480 		if (ifr->ifr_mtu < ETHERMIN || ifr->ifr_mtu > maxmtu)
   1481 			return EINVAL;
   1482 		else if ((error = ifioctl_common(ifp, cmd, data)) != ENETRESET)
   1483 			return error;
   1484 		else if (ifp->if_flags & IFF_UP) {
   1485 			/* Make sure the device notices the MTU change. */
   1486 			return (*ifp->if_init)(ifp);
   1487 		} else
   1488 			return 0;
   1489 	    }
   1490 
   1491 	case SIOCSIFFLAGS:
   1492 		if ((error = ifioctl_common(ifp, cmd, data)) != 0)
   1493 			return error;
   1494 		switch (ifp->if_flags & (IFF_UP|IFF_RUNNING)) {
   1495 		case IFF_RUNNING:
   1496 			/*
   1497 			 * If interface is marked down and it is running,
   1498 			 * then stop and disable it.
   1499 			 */
   1500 			(*ifp->if_stop)(ifp, 1);
   1501 			break;
   1502 		case IFF_UP:
   1503 			/*
   1504 			 * If interface is marked up and it is stopped, then
   1505 			 * start it.
   1506 			 */
   1507 			return (*ifp->if_init)(ifp);
   1508 		case IFF_UP|IFF_RUNNING:
   1509 			error = 0;
   1510 			if (ec->ec_ifflags_cb == NULL ||
   1511 			    (error = (*ec->ec_ifflags_cb)(ec)) == ENETRESET) {
   1512 				/*
   1513 				 * Reset the interface to pick up
   1514 				 * changes in any other flags that
   1515 				 * affect the hardware state.
   1516 				 */
   1517 				return (*ifp->if_init)(ifp);
   1518 			} else
   1519 				return error;
   1520 		case 0:
   1521 			break;
   1522 		}
   1523 		return 0;
   1524 	case SIOCADDMULTI:
   1525 		return ether_addmulti(ifreq_getaddr(cmd, ifr), ec);
   1526 	case SIOCDELMULTI:
   1527 		return ether_delmulti(ifreq_getaddr(cmd, ifr), ec);
   1528 	case SIOCSIFMEDIA:
   1529 	case SIOCGIFMEDIA:
   1530 		if (ec->ec_mii == NULL)
   1531 			return ENOTTY;
   1532 		return ifmedia_ioctl(ifp, ifr, &ec->ec_mii->mii_media, cmd);
   1533 	case SIOCALIFADDR:
   1534 		sdl = satocsdl(sstocsa(&iflr->addr));
   1535 		if (sdl->sdl_family != AF_LINK)
   1536 			;
   1537 		else if (ETHER_IS_MULTICAST(CLLADDR(sdl)))
   1538 			return EINVAL;
   1539 		else if (memcmp(zero, CLLADDR(sdl), sizeof(zero)) == 0)
   1540 			return EINVAL;
   1541 		/*FALLTHROUGH*/
   1542 	default:
   1543 		return ifioctl_common(ifp, cmd, data);
   1544 	}
   1545 	return 0;
   1546 }
   1547