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if_ethersubr.c revision 1.128.8.5
      1 /*	$NetBSD: if_ethersubr.c,v 1.128.8.5 2006/09/14 12:31:54 yamt Exp $	*/
      2 
      3 /*
      4  * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
      5  * All rights reserved.
      6  *
      7  * Redistribution and use in source and binary forms, with or without
      8  * modification, are permitted provided that the following conditions
      9  * are met:
     10  * 1. Redistributions of source code must retain the above copyright
     11  *    notice, this list of conditions and the following disclaimer.
     12  * 2. Redistributions in binary form must reproduce the above copyright
     13  *    notice, this list of conditions and the following disclaimer in the
     14  *    documentation and/or other materials provided with the distribution.
     15  * 3. Neither the name of the project nor the names of its contributors
     16  *    may be used to endorse or promote products derived from this software
     17  *    without specific prior written permission.
     18  *
     19  * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
     20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
     23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     29  * SUCH DAMAGE.
     30  */
     31 
     32 /*
     33  * Copyright (c) 1982, 1989, 1993
     34  *	The Regents of the University of California.  All rights reserved.
     35  *
     36  * Redistribution and use in source and binary forms, with or without
     37  * modification, are permitted provided that the following conditions
     38  * are met:
     39  * 1. Redistributions of source code must retain the above copyright
     40  *    notice, this list of conditions and the following disclaimer.
     41  * 2. Redistributions in binary form must reproduce the above copyright
     42  *    notice, this list of conditions and the following disclaimer in the
     43  *    documentation and/or other materials provided with the distribution.
     44  * 3. Neither the name of the University nor the names of its contributors
     45  *    may be used to endorse or promote products derived from this software
     46  *    without specific prior written permission.
     47  *
     48  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
     49  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     50  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     51  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
     52  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     53  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     54  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     55  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     56  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     57  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     58  * SUCH DAMAGE.
     59  *
     60  *	@(#)if_ethersubr.c	8.2 (Berkeley) 4/4/96
     61  */
     62 
     63 #include <sys/cdefs.h>
     64 __KERNEL_RCSID(0, "$NetBSD: if_ethersubr.c,v 1.128.8.5 2006/09/14 12:31:54 yamt 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 
     94 #include <machine/cpu.h>
     95 
     96 #include <net/if.h>
     97 #include <net/netisr.h>
     98 #include <net/route.h>
     99 #include <net/if_llc.h>
    100 #include <net/if_dl.h>
    101 #include <net/if_types.h>
    102 
    103 #if NARP == 0
    104 /*
    105  * XXX there should really be a way to issue this warning from within config(8)
    106  */
    107 #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.
    108 #endif
    109 
    110 #if NBPFILTER > 0
    111 #include <net/bpf.h>
    112 #endif
    113 
    114 #include <net/if_ether.h>
    115 #if NVLAN > 0
    116 #include <net/if_vlanvar.h>
    117 #endif
    118 
    119 #if NPPPOE > 0
    120 #include <net/if_pppoe.h>
    121 #endif
    122 
    123 #if NAGR > 0
    124 #include <net/agr/ieee8023_slowprotocols.h>	/* XXX */
    125 #include <net/agr/ieee8023ad.h>
    126 #include <net/agr/if_agrvar.h>
    127 #endif
    128 
    129 #if NBRIDGE > 0
    130 #include <net/if_bridgevar.h>
    131 #endif
    132 
    133 #include <netinet/in.h>
    134 #ifdef INET
    135 #include <netinet/in_var.h>
    136 #endif
    137 #include <netinet/if_inarp.h>
    138 
    139 #ifdef INET6
    140 #ifndef INET
    141 #include <netinet/in.h>
    142 #endif
    143 #include <netinet6/in6_var.h>
    144 #include <netinet6/nd6.h>
    145 #endif
    146 
    147 
    148 #include "carp.h"
    149 #if NCARP > 0
    150 #include <netinet/ip_carp.h>
    151 #endif
    152 
    153 #ifdef IPX
    154 #include <netipx/ipx.h>
    155 #include <netipx/ipx_if.h>
    156 #endif
    157 
    158 #ifdef ISO
    159 #include <netiso/argo_debug.h>
    160 #include <netiso/iso.h>
    161 #include <netiso/iso_var.h>
    162 #include <netiso/iso_snpac.h>
    163 #endif
    164 
    165 
    166 
    167 #ifdef NETATALK
    168 #include <netatalk/at.h>
    169 #include <netatalk/at_var.h>
    170 #include <netatalk/at_extern.h>
    171 
    172 #define llc_snap_org_code llc_un.type_snap.org_code
    173 #define llc_snap_ether_type llc_un.type_snap.ether_type
    174 
    175 extern u_char	at_org_code[3];
    176 extern u_char	aarp_org_code[3];
    177 #endif /* NETATALK */
    178 
    179 static struct timeval bigpktppslim_last;
    180 static int bigpktppslim = 2;	/* XXX */
    181 static int bigpktpps_count;
    182 
    183 
    184 const uint8_t etherbroadcastaddr[ETHER_ADDR_LEN] =
    185     { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff };
    186 const uint8_t ethermulticastaddr_slowprotocols[ETHER_ADDR_LEN] =
    187     { 0x01, 0x80, 0xc2, 0x00, 0x00, 0x02 };
    188 #define senderr(e) { error = (e); goto bad;}
    189 
    190 #define SIN(x) ((struct sockaddr_in *)x)
    191 
    192 static	int ether_output(struct ifnet *, struct mbuf *,
    193 	    struct sockaddr *, struct rtentry *);
    194 
    195 /*
    196  * Ethernet output routine.
    197  * Encapsulate a packet of type family for the local net.
    198  * Assumes that ifp is actually pointer to ethercom structure.
    199  */
    200 static int
    201 ether_output(struct ifnet *ifp0, struct mbuf *m0, struct sockaddr *dst,
    202 	struct rtentry *rt0)
    203 {
    204 	u_int16_t etype = 0;
    205 	int error = 0, hdrcmplt = 0;
    206  	u_char esrc[6], edst[6];
    207 	struct mbuf *m = m0;
    208 	struct rtentry *rt;
    209 	struct mbuf *mcopy = (struct mbuf *)0;
    210 	struct ether_header *eh;
    211 	struct ifnet *ifp = ifp0;
    212 	ALTQ_DECL(struct altq_pktattr pktattr;)
    213 #ifdef INET
    214 	struct arphdr *ah;
    215 #endif /* INET */
    216 #ifdef NETATALK
    217 	struct at_ifaddr *aa;
    218 #endif /* NETATALK */
    219 
    220 #ifdef MBUFTRACE
    221 	m_claimm(m, ifp->if_mowner);
    222 #endif
    223 
    224 #if NCARP > 0
    225 	if (ifp->if_type == IFT_CARP) {
    226 		struct ifaddr *ifa;
    227 
    228 		/* loop back if this is going to the carp interface */
    229 		if (dst != NULL && ifp0->if_link_state == LINK_STATE_UP &&
    230 		    (ifa = ifa_ifwithaddr(dst)) != NULL &&
    231 		    ifa->ifa_ifp == ifp0)
    232 			return (looutput(ifp0, m, dst, rt0));
    233 
    234 		ifp = ifp->if_carpdev;
    235 		/* ac = (struct arpcom *)ifp; */
    236 
    237 		if ((ifp0->if_flags & (IFF_UP|IFF_RUNNING)) !=
    238 		    (IFF_UP|IFF_RUNNING))
    239 			senderr(ENETDOWN);
    240 	}
    241 #endif /* NCARP > 0 */
    242 
    243 	if ((ifp->if_flags & (IFF_UP|IFF_RUNNING)) != (IFF_UP|IFF_RUNNING))
    244 		senderr(ENETDOWN);
    245 	if ((rt = rt0) != NULL) {
    246 		if ((rt->rt_flags & RTF_UP) == 0) {
    247 			if ((rt0 = rt = rtalloc1(dst, 1)) != NULL) {
    248 				rt->rt_refcnt--;
    249 				if (rt->rt_ifp != ifp)
    250 					return (*rt->rt_ifp->if_output)
    251 							(ifp, m0, dst, rt);
    252 			} else
    253 				senderr(EHOSTUNREACH);
    254 		}
    255 		if ((rt->rt_flags & RTF_GATEWAY) && dst->sa_family != AF_NS) {
    256 			if (rt->rt_gwroute == 0)
    257 				goto lookup;
    258 			if (((rt = rt->rt_gwroute)->rt_flags & RTF_UP) == 0) {
    259 				rtfree(rt); rt = rt0;
    260 			lookup: rt->rt_gwroute = rtalloc1(rt->rt_gateway, 1);
    261 				if ((rt = rt->rt_gwroute) == 0)
    262 					senderr(EHOSTUNREACH);
    263 				/* the "G" test below also prevents rt == rt0 */
    264 				if ((rt->rt_flags & RTF_GATEWAY) ||
    265 				    (rt->rt_ifp != ifp)) {
    266 					rt->rt_refcnt--;
    267 					rt0->rt_gwroute = 0;
    268 					senderr(EHOSTUNREACH);
    269 				}
    270 			}
    271 		}
    272 		if (rt->rt_flags & RTF_REJECT)
    273 			if (rt->rt_rmx.rmx_expire == 0 ||
    274 			    (u_long) time_second < rt->rt_rmx.rmx_expire)
    275 				senderr(rt == rt0 ? EHOSTDOWN : EHOSTUNREACH);
    276 	}
    277 
    278 	switch (dst->sa_family) {
    279 
    280 #ifdef INET
    281 	case AF_INET:
    282 		if (m->m_flags & M_BCAST)
    283                 	(void)memcpy(edst, etherbroadcastaddr, sizeof(edst));
    284 
    285 		else if (m->m_flags & M_MCAST) {
    286 			ETHER_MAP_IP_MULTICAST(&SIN(dst)->sin_addr,
    287 			    (caddr_t)edst)
    288 
    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 			caddr_t tha = ar_tha(ah);
    303 
    304 			KASSERT(tha);
    305 			bcopy(tha, (caddr_t)edst, 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, (u_char *)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, (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 		    (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 			bcopy(at_org_code, llc.llc_snap_org_code,
    362 			    sizeof(llc.llc_snap_org_code));
    363 			llc.llc_snap_ether_type = htons(ETHERTYPE_ATALK);
    364 			bcopy(&llc, mtod(m, caddr_t), 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  		bcopy((caddr_t)&(((struct sockaddr_ipx *)dst)->sipx_addr.x_host),
    374 		    (caddr_t)edst, sizeof (edst));
    375 		/* If broadcasting on a simplex interface, loopback a copy */
    376 		if ((m->m_flags & M_BCAST) && (ifp->if_flags & IFF_SIMPLEX))
    377 			mcopy = m_copy(m, 0, (int)M_COPYALL);
    378 		break;
    379 #endif
    380 #ifdef	ISO
    381 	case AF_ISO: {
    382 		int	snpalen;
    383 		struct	llc *l;
    384 		struct sockaddr_dl *sdl;
    385 
    386 		if (rt && (sdl = (struct sockaddr_dl *)rt->rt_gateway) &&
    387 		    sdl->sdl_family == AF_LINK && sdl->sdl_alen > 0) {
    388 			bcopy(LLADDR(sdl), (caddr_t)edst, sizeof(edst));
    389 		} else {
    390 			error = iso_snparesolve(ifp, (struct sockaddr_iso *)dst,
    391 						(char *)edst, &snpalen);
    392 			if (error)
    393 				goto bad; /* Not Resolved */
    394 		}
    395 		/* If broadcasting on a simplex interface, loopback a copy */
    396 		if (*edst & 1)
    397 			m->m_flags |= (M_BCAST|M_MCAST);
    398 		if ((m->m_flags & M_BCAST) && (ifp->if_flags & IFF_SIMPLEX) &&
    399 		    (mcopy = m_copy(m, 0, (int)M_COPYALL))) {
    400 			M_PREPEND(mcopy, sizeof (*eh), M_DONTWAIT);
    401 			if (mcopy) {
    402 				eh = mtod(mcopy, struct ether_header *);
    403 				bcopy((caddr_t)edst,
    404 				      (caddr_t)eh->ether_dhost, sizeof (edst));
    405 				bcopy(LLADDR(ifp->if_sadl),
    406 				      (caddr_t)eh->ether_shost, sizeof (edst));
    407 			}
    408 		}
    409 		M_PREPEND(m, 3, M_DONTWAIT);
    410 		if (m == NULL)
    411 			return (0);
    412 		l = mtod(m, struct llc *);
    413 		l->llc_dsap = l->llc_ssap = LLC_ISO_LSAP;
    414 		l->llc_control = LLC_UI;
    415 #ifdef ARGO_DEBUG
    416 		if (argo_debug[D_ETHER]) {
    417 			int i;
    418 			printf("unoutput: sending pkt to: ");
    419 			for (i=0; i<6; i++)
    420 				printf("%x ", edst[i] & 0xff);
    421 			printf("\n");
    422 		}
    423 #endif
    424 		} break;
    425 #endif /* ISO */
    426 
    427 	case pseudo_AF_HDRCMPLT:
    428 		hdrcmplt = 1;
    429 		eh = (struct ether_header *)dst->sa_data;
    430 		bcopy((caddr_t)eh->ether_shost, (caddr_t)esrc, sizeof (esrc));
    431 		/* FALLTHROUGH */
    432 
    433 	case AF_UNSPEC:
    434 		eh = (struct ether_header *)dst->sa_data;
    435  		bcopy((caddr_t)eh->ether_dhost, (caddr_t)edst, sizeof (edst));
    436 		/* AF_UNSPEC doesn't swap the byte order of the ether_type. */
    437 		etype = eh->ether_type;
    438 		break;
    439 
    440 	default:
    441 		printf("%s: can't handle af%d\n", ifp->if_xname,
    442 			dst->sa_family);
    443 		senderr(EAFNOSUPPORT);
    444 	}
    445 
    446 	if (mcopy)
    447 		(void) looutput(ifp, mcopy, dst, rt);
    448 
    449 	/* If no ether type is set, this must be a 802.2 formatted packet.
    450 	 */
    451 	if (etype == 0)
    452 		etype = htons(m->m_pkthdr.len);
    453 	/*
    454 	 * Add local net header.  If no space in first mbuf,
    455 	 * allocate another.
    456 	 */
    457 	M_PREPEND(m, sizeof (struct ether_header), M_DONTWAIT);
    458 	if (m == 0)
    459 		senderr(ENOBUFS);
    460 	eh = mtod(m, struct ether_header *);
    461 	/* Note: etype is already in network byte order. */
    462 #ifdef __NO_STRICT_ALIGNMENT
    463 	eh->ether_type = etype;
    464 #else
    465 	{
    466 		uint8_t *dstp = (uint8_t *) &eh->ether_type;
    467 #if BYTE_ORDER == BIG_ENDIAN
    468 		dstp[0] = etype >> 8;
    469 		dstp[1] = etype;
    470 #else
    471 		dstp[0] = etype;
    472 		dstp[1] = etype >> 8;
    473 #endif /* BYTE_ORDER == BIG_ENDIAN */
    474 	}
    475 #endif /* __NO_STRICT_ALIGNMENT */
    476  	bcopy((caddr_t)edst, (caddr_t)eh->ether_dhost, sizeof (edst));
    477 	if (hdrcmplt)
    478 		bcopy((caddr_t)esrc, (caddr_t)eh->ether_shost,
    479 		    sizeof(eh->ether_shost));
    480 	else
    481 	 	bcopy(LLADDR(ifp->if_sadl), (caddr_t)eh->ether_shost,
    482 		    sizeof(eh->ether_shost));
    483 
    484 #if NCARP > 0
    485 	if (ifp0 != ifp && ifp0->if_type == IFT_CARP) {
    486 	 	bcopy(LLADDR(ifp0->if_sadl), (caddr_t)eh->ether_shost,
    487 		    sizeof(eh->ether_shost));
    488 	}
    489 #endif /* NCARP > 0 */
    490 
    491 #ifdef PFIL_HOOKS
    492 	if ((error = pfil_run_hooks(&ifp->if_pfil, &m, ifp, PFIL_OUT)) != 0)
    493 		return (error);
    494 	if (m == NULL)
    495 		return (0);
    496 #endif
    497 
    498 #if NBRIDGE > 0
    499 	/*
    500 	 * Bridges require special output handling.
    501 	 */
    502 	if (ifp->if_bridge)
    503 		return (bridge_output(ifp, m, NULL, NULL));
    504 #endif
    505 
    506 #if NCARP > 0
    507 	if (ifp != ifp0)
    508 		ifp0->if_obytes += m->m_pkthdr.len + ETHER_HDR_LEN;
    509 #endif /* NCARP > 0 */
    510 
    511 #ifdef ALTQ
    512 	/*
    513 	 * If ALTQ is enabled on the parent interface, do
    514 	 * classification; the queueing discipline might not
    515 	 * require classification, but might require the
    516 	 * address family/header pointer in the pktattr.
    517 	 */
    518 	if (ALTQ_IS_ENABLED(&ifp->if_snd))
    519 		altq_etherclassify(&ifp->if_snd, m, &pktattr);
    520 #endif
    521 
    522 	return ifq_enqueue(ifp, m ALTQ_COMMA ALTQ_DECL(&pktattr));
    523 
    524 bad:
    525 	if (m)
    526 		m_freem(m);
    527 	return (error);
    528 }
    529 
    530 #ifdef ALTQ
    531 /*
    532  * This routine is a slight hack to allow a packet to be classified
    533  * if the Ethernet headers are present.  It will go away when ALTQ's
    534  * classification engine understands link headers.
    535  */
    536 void
    537 altq_etherclassify(struct ifaltq *ifq, struct mbuf *m,
    538     struct altq_pktattr *pktattr)
    539 {
    540 	struct ether_header *eh;
    541 	u_int16_t ether_type;
    542 	int hlen, af, hdrsize;
    543 	caddr_t hdr;
    544 
    545 	hlen = ETHER_HDR_LEN;
    546 	eh = mtod(m, struct ether_header *);
    547 
    548 	ether_type = htons(eh->ether_type);
    549 
    550 	if (ether_type < ETHERMTU) {
    551 		/* LLC/SNAP */
    552 		struct llc *llc = (struct llc *)(eh + 1);
    553 		hlen += 8;
    554 
    555 		if (m->m_len < hlen ||
    556 		    llc->llc_dsap != LLC_SNAP_LSAP ||
    557 		    llc->llc_ssap != LLC_SNAP_LSAP ||
    558 		    llc->llc_control != LLC_UI) {
    559 			/* Not SNAP. */
    560 			goto bad;
    561 		}
    562 
    563 		ether_type = htons(llc->llc_un.type_snap.ether_type);
    564 	}
    565 
    566 	switch (ether_type) {
    567 	case ETHERTYPE_IP:
    568 		af = AF_INET;
    569 		hdrsize = 20;		/* sizeof(struct ip) */
    570 		break;
    571 
    572 	case ETHERTYPE_IPV6:
    573 		af = AF_INET6;
    574 		hdrsize = 40;		/* sizeof(struct ip6_hdr) */
    575 		break;
    576 
    577 	default:
    578 		af = AF_UNSPEC;
    579 		hdrsize = 0;
    580 		break;
    581 	}
    582 
    583 	while (m->m_len <= hlen) {
    584 		hlen -= m->m_len;
    585 		m = m->m_next;
    586 	}
    587 	if (m->m_len < (hlen + hdrsize)) {
    588 		/*
    589 		 * protocol header not in a single mbuf.
    590 		 * We can't cope with this situation right
    591 		 * now (but it shouldn't ever happen, really, anyhow).
    592 		 */
    593 #ifdef DEBUG
    594 		printf("altq_etherclassify: headers span multiple mbufs: "
    595 		    "%d < %d\n", m->m_len, (hlen + hdrsize));
    596 #endif
    597 		goto bad;
    598 	}
    599 
    600 	m->m_data += hlen;
    601 	m->m_len -= hlen;
    602 
    603 	hdr = mtod(m, caddr_t);
    604 
    605 	if (ALTQ_NEEDS_CLASSIFY(ifq))
    606 		pktattr->pattr_class =
    607 		    (*ifq->altq_classify)(ifq->altq_clfier, m, af);
    608 	pktattr->pattr_af = af;
    609 	pktattr->pattr_hdr = hdr;
    610 
    611 	m->m_data -= hlen;
    612 	m->m_len += hlen;
    613 
    614 	return;
    615 
    616  bad:
    617 	pktattr->pattr_class = NULL;
    618 	pktattr->pattr_hdr = NULL;
    619 	pktattr->pattr_af = AF_UNSPEC;
    620 }
    621 #endif /* ALTQ */
    622 
    623 /*
    624  * Process a received Ethernet packet;
    625  * the packet is in the mbuf chain m with
    626  * the ether header.
    627  */
    628 void
    629 ether_input(struct ifnet *ifp, struct mbuf *m)
    630 {
    631 	struct ethercom *ec = (struct ethercom *) ifp;
    632 	struct ifqueue *inq;
    633 	u_int16_t etype;
    634 	struct ether_header *eh;
    635 #if defined (ISO) || defined (LLC) || defined(NETATALK)
    636 	struct llc *l;
    637 #endif
    638 
    639 	if ((ifp->if_flags & IFF_UP) == 0) {
    640 		m_freem(m);
    641 		return;
    642 	}
    643 
    644 #ifdef MBUFTRACE
    645 	m_claimm(m, &ec->ec_rx_mowner);
    646 #endif
    647 	eh = mtod(m, struct ether_header *);
    648 	etype = ntohs(eh->ether_type);
    649 
    650 	/*
    651 	 * Determine if the packet is within its size limits.
    652 	 */
    653 	if (m->m_pkthdr.len >
    654 	    ETHER_MAX_FRAME(ifp, etype, m->m_flags & M_HASFCS)) {
    655 		if (ppsratecheck(&bigpktppslim_last, &bigpktpps_count,
    656 			    bigpktppslim)) {
    657 			printf("%s: discarding oversize frame (len=%d)\n",
    658 			    ifp->if_xname, m->m_pkthdr.len);
    659 		}
    660 		m_freem(m);
    661 		return;
    662 	}
    663 
    664 	if (ETHER_IS_MULTICAST(eh->ether_dhost)) {
    665 		/*
    666 		 * If this is not a simplex interface, drop the packet
    667 		 * if it came from us.
    668 		 */
    669 		if ((ifp->if_flags & IFF_SIMPLEX) == 0 &&
    670 		    memcmp(LLADDR(ifp->if_sadl), eh->ether_shost,
    671 		    ETHER_ADDR_LEN) == 0) {
    672 			m_freem(m);
    673 			return;
    674 		}
    675 
    676 		if (memcmp(etherbroadcastaddr,
    677 		    eh->ether_dhost, ETHER_ADDR_LEN) == 0)
    678 			m->m_flags |= M_BCAST;
    679 		else
    680 			m->m_flags |= M_MCAST;
    681 		ifp->if_imcasts++;
    682 	}
    683 
    684 	/* If the CRC is still on the packet, trim it off. */
    685 	if (m->m_flags & M_HASFCS) {
    686 		m_adj(m, -ETHER_CRC_LEN);
    687 		m->m_flags &= ~M_HASFCS;
    688 	}
    689 
    690 	ifp->if_ibytes += m->m_pkthdr.len;
    691 
    692 #if NBRIDGE > 0
    693 	/*
    694 	 * Tap the packet off here for a bridge.  bridge_input()
    695 	 * will return NULL if it has consumed the packet, otherwise
    696 	 * it gets processed as normal.  Note that bridge_input()
    697 	 * will always return the original packet if we need to
    698 	 * process it locally.
    699 	 */
    700 	if (ifp->if_bridge) {
    701 		if(m->m_flags & M_PROTO1) {
    702 			m->m_flags &= ~M_PROTO1;
    703 		} else {
    704 			/* clear M_PROMISC, in case the packets comes from a vlan */
    705 			m->m_flags &= ~M_PROMISC;
    706 			m = bridge_input(ifp, m);
    707 			if (m == NULL)
    708 				return;
    709 
    710 			/*
    711 			 * Bridge has determined that the packet is for us.
    712 			 * Update our interface pointer -- we may have had
    713 			 * to "bridge" the packet locally.
    714 			 */
    715 			ifp = m->m_pkthdr.rcvif;
    716 		}
    717 	} else
    718 #endif /* NBRIDGE > 0 */
    719 	{
    720 
    721 #if NCARP > 0
    722 		if (ifp->if_carp && ifp->if_type != IFT_CARP &&
    723 		    (carp_input(m, (u_int8_t *)&eh->ether_shost,
    724 		    (u_int8_t *)&eh->ether_dhost, eh->ether_type) == 0)) {
    725 			return;
    726 		}
    727 #endif /* NCARP > 0 */
    728 		if ((m->m_flags & (M_BCAST|M_MCAST)) == 0 &&
    729 		    (ifp->if_flags & IFF_PROMISC) != 0 &&
    730 		    memcmp(LLADDR(ifp->if_sadl), eh->ether_dhost,
    731 			   ETHER_ADDR_LEN) != 0) {
    732 			m->m_flags |= M_PROMISC;
    733 		}
    734 	}
    735 
    736 #ifdef PFIL_HOOKS
    737 	if ((m->m_flags & M_PROMISC) == 0) {
    738 		if (pfil_run_hooks(&ifp->if_pfil, &m, ifp, PFIL_IN) != 0)
    739 			return;
    740 		if (m == NULL)
    741 			return;
    742 
    743 		eh = mtod(m, struct ether_header *);
    744 		etype = ntohs(eh->ether_type);
    745 	}
    746 #endif
    747 
    748 	/*
    749 	 * If VLANs are configured on the interface, check to
    750 	 * see if the device performed the decapsulation and
    751 	 * provided us with the tag.
    752 	 */
    753 	if (ec->ec_nvlans && m_tag_find(m, PACKET_TAG_VLAN, NULL) != NULL) {
    754 #if NVLAN > 0
    755 		/*
    756 		 * vlan_input() will either recursively call ether_input()
    757 		 * or drop the packet.
    758 		 */
    759 		vlan_input(ifp, m);
    760 #else
    761 		m_freem(m);
    762 #endif
    763 		return;
    764 	}
    765 
    766 #if NAGR > 0
    767 	if (ifp->if_agrprivate &&
    768 	    __predict_true(etype != ETHERTYPE_SLOWPROTOCOLS)) {
    769 		m->m_flags &= ~M_PROMISC;
    770 		agr_input(ifp, m);
    771 		return;
    772 	}
    773 #endif /* NAGR > 0 */
    774 
    775 	/*
    776 	 * Handle protocols that expect to have the Ethernet header
    777 	 * (and possibly FCS) intact.
    778 	 */
    779 	switch (etype) {
    780 #if NVLAN > 0
    781 	case ETHERTYPE_VLAN:
    782 		/*
    783 		 * vlan_input() will either recursively call ether_input()
    784 		 * or drop the packet.
    785 		 */
    786 		if (((struct ethercom *)ifp)->ec_nvlans != 0)
    787 			vlan_input(ifp, m);
    788 		else
    789 			m_freem(m);
    790 		return;
    791 #endif /* NVLAN > 0 */
    792 #if NPPPOE > 0
    793 	case ETHERTYPE_PPPOEDISC:
    794 	case ETHERTYPE_PPPOE:
    795 		if (m->m_flags & M_PROMISC) {
    796 			m_freem(m);
    797 			return;
    798 		}
    799 #ifndef PPPOE_SERVER
    800 		if (m->m_flags & (M_MCAST | M_BCAST)) {
    801 			m_freem(m);
    802 			return;
    803 		}
    804 #endif
    805 
    806 		if (etype == ETHERTYPE_PPPOEDISC)
    807 			inq = &ppoediscinq;
    808 		else
    809 			inq = &ppoeinq;
    810 		if (IF_QFULL(inq)) {
    811 			IF_DROP(inq);
    812 			m_freem(m);
    813 		} else
    814 			IF_ENQUEUE(inq, m);
    815 #ifndef __HAVE_GENERIC_SOFT_INTERRUPTS
    816 		if (!callout_pending(&pppoe_softintr))
    817 			callout_reset(&pppoe_softintr, 1, pppoe_softintr_handler, NULL);
    818 #else
    819 		softintr_schedule(pppoe_softintr);
    820 #endif
    821 		return;
    822 #endif /* NPPPOE > 0 */
    823 	case ETHERTYPE_SLOWPROTOCOLS: {
    824 		uint8_t subtype;
    825 
    826 #if defined(DIAGNOSTIC)
    827 		if (m->m_pkthdr.len < sizeof(*eh) + sizeof(subtype)) {
    828 			panic("ether_input: too short slow protocol packet");
    829 		}
    830 #endif
    831 		m_copydata(m, sizeof(*eh), sizeof(subtype), &subtype);
    832 		switch (subtype) {
    833 #if NAGR > 0
    834 		case SLOWPROTOCOLS_SUBTYPE_LACP:
    835 			if (ifp->if_agrprivate) {
    836 				ieee8023ad_lacp_input(ifp, m);
    837 				return;
    838 			}
    839 			break;
    840 
    841 		case SLOWPROTOCOLS_SUBTYPE_MARKER:
    842 			if (ifp->if_agrprivate) {
    843 				ieee8023ad_marker_input(ifp, m);
    844 				return;
    845 			}
    846 			break;
    847 #endif /* NAGR > 0 */
    848 		default:
    849 			if (subtype == 0 || subtype > 10) {
    850 				/* illegal value */
    851 				m_freem(m);
    852 				return;
    853 			}
    854 			/* unknown subtype */
    855 			break;
    856 		}
    857 		/* FALLTHROUGH */
    858 	}
    859 	default:
    860 		if (m->m_flags & M_PROMISC) {
    861 			m_freem(m);
    862 			return;
    863 		}
    864 	}
    865 
    866 	/* Strip off the Ethernet header. */
    867 	m_adj(m, sizeof(struct ether_header));
    868 
    869 	/* If the CRC is still on the packet, trim it off. */
    870 	if (m->m_flags & M_HASFCS) {
    871 		m_adj(m, -ETHER_CRC_LEN);
    872 		m->m_flags &= ~M_HASFCS;
    873 	}
    874 
    875 	switch (etype) {
    876 #ifdef INET
    877 	case ETHERTYPE_IP:
    878 #ifdef GATEWAY
    879 		if (ipflow_fastforward(m))
    880 			return;
    881 #endif
    882 		schednetisr(NETISR_IP);
    883 		inq = &ipintrq;
    884 		break;
    885 
    886 	case ETHERTYPE_ARP:
    887 		schednetisr(NETISR_ARP);
    888 		inq = &arpintrq;
    889 		break;
    890 
    891 	case ETHERTYPE_REVARP:
    892 		revarpinput(m);	/* XXX queue? */
    893 		return;
    894 #endif
    895 #ifdef INET6
    896 	case ETHERTYPE_IPV6:
    897 		schednetisr(NETISR_IPV6);
    898 		inq = &ip6intrq;
    899 		break;
    900 #endif
    901 #ifdef IPX
    902 	case ETHERTYPE_IPX:
    903 		schednetisr(NETISR_IPX);
    904 		inq = &ipxintrq;
    905 		break;
    906 #endif
    907 #ifdef NETATALK
    908         case ETHERTYPE_ATALK:
    909                 schednetisr(NETISR_ATALK);
    910                 inq = &atintrq1;
    911                 break;
    912         case ETHERTYPE_AARP:
    913 		/* probably this should be done with a NETISR as well */
    914                 aarpinput(ifp, m); /* XXX */
    915                 return;
    916 #endif /* NETATALK */
    917 	default:
    918 #if defined (ISO) || defined (LLC) || defined (NETATALK)
    919 		if (etype > ETHERMTU)
    920 			goto dropanyway;
    921 		l = mtod(m, struct llc *);
    922 		switch (l->llc_dsap) {
    923 #ifdef NETATALK
    924 		case LLC_SNAP_LSAP:
    925 			switch (l->llc_control) {
    926 			case LLC_UI:
    927 				if (l->llc_ssap != LLC_SNAP_LSAP) {
    928 					goto dropanyway;
    929 				}
    930 
    931 				if (Bcmp(&(l->llc_snap_org_code)[0],
    932 				    at_org_code, sizeof(at_org_code)) == 0 &&
    933 				    ntohs(l->llc_snap_ether_type) ==
    934 				    ETHERTYPE_ATALK) {
    935 					inq = &atintrq2;
    936 					m_adj(m, sizeof(struct llc));
    937 					schednetisr(NETISR_ATALK);
    938 					break;
    939 				}
    940 
    941 				if (Bcmp(&(l->llc_snap_org_code)[0],
    942 				    aarp_org_code,
    943 				    sizeof(aarp_org_code)) == 0 &&
    944 				    ntohs(l->llc_snap_ether_type) ==
    945 				    ETHERTYPE_AARP) {
    946 					m_adj( m, sizeof(struct llc));
    947 					aarpinput(ifp, m); /* XXX */
    948 				    return;
    949 				}
    950 
    951 			default:
    952 				goto dropanyway;
    953 			}
    954 			break;
    955 #endif /* NETATALK */
    956 #ifdef	ISO
    957 		case LLC_ISO_LSAP:
    958 			switch (l->llc_control) {
    959 			case LLC_UI:
    960 				/* LLC_UI_P forbidden in class 1 service */
    961 				if ((l->llc_dsap == LLC_ISO_LSAP) &&
    962 				    (l->llc_ssap == LLC_ISO_LSAP)) {
    963 					/* LSAP for ISO */
    964 					if (m->m_pkthdr.len > etype)
    965 						m_adj(m, etype - m->m_pkthdr.len);
    966 					m->m_data += 3;		/* XXX */
    967 					m->m_len -= 3;		/* XXX */
    968 					m->m_pkthdr.len -= 3;	/* XXX */
    969 					M_PREPEND(m, sizeof *eh, M_DONTWAIT);
    970 					if (m == 0)
    971 						return;
    972 					*mtod(m, struct ether_header *) = *eh;
    973 #ifdef ARGO_DEBUG
    974 					if (argo_debug[D_ETHER])
    975 						printf("clnp packet");
    976 #endif
    977 					schednetisr(NETISR_ISO);
    978 					inq = &clnlintrq;
    979 					break;
    980 				}
    981 				goto dropanyway;
    982 
    983 			case LLC_XID:
    984 			case LLC_XID_P:
    985 				if(m->m_len < 6)
    986 					goto dropanyway;
    987 				l->llc_window = 0;
    988 				l->llc_fid = 9;
    989 				l->llc_class = 1;
    990 				l->llc_dsap = l->llc_ssap = 0;
    991 				/* Fall through to */
    992 			case LLC_TEST:
    993 			case LLC_TEST_P:
    994 			{
    995 				struct sockaddr sa;
    996 				struct ether_header *eh2;
    997 				int i;
    998 				u_char c = l->llc_dsap;
    999 
   1000 				l->llc_dsap = l->llc_ssap;
   1001 				l->llc_ssap = c;
   1002 				if (m->m_flags & (M_BCAST | M_MCAST))
   1003 					bcopy(LLADDR(ifp->if_sadl),
   1004 					      (caddr_t)eh->ether_dhost, 6);
   1005 				sa.sa_family = AF_UNSPEC;
   1006 				sa.sa_len = sizeof(sa);
   1007 				eh2 = (struct ether_header *)sa.sa_data;
   1008 				for (i = 0; i < 6; i++) {
   1009 					eh2->ether_shost[i] = c =
   1010 					    eh->ether_dhost[i];
   1011 					eh2->ether_dhost[i] =
   1012 					    eh->ether_dhost[i] =
   1013 					    eh->ether_shost[i];
   1014 					eh->ether_shost[i] = c;
   1015 				}
   1016 				ifp->if_output(ifp, m, &sa, NULL);
   1017 				return;
   1018 			}
   1019 			default:
   1020 				m_freem(m);
   1021 				return;
   1022 			}
   1023 			break;
   1024 #endif /* ISO */
   1025 		dropanyway:
   1026 		default:
   1027 			m_freem(m);
   1028 			return;
   1029 		}
   1030 #else /* ISO || LLC  || NETATALK*/
   1031 	    m_freem(m);
   1032 	    return;
   1033 #endif /* ISO || LLC || NETATALK*/
   1034 	}
   1035 
   1036 	if (IF_QFULL(inq)) {
   1037 		IF_DROP(inq);
   1038 		m_freem(m);
   1039 	} else
   1040 		IF_ENQUEUE(inq, m);
   1041 }
   1042 
   1043 /*
   1044  * Convert Ethernet address to printable (loggable) representation.
   1045  */
   1046 char *
   1047 ether_sprintf(const u_char *ap)
   1048 {
   1049 	static char etherbuf[3 * ETHER_ADDR_LEN];
   1050 	return ether_snprintf(etherbuf, sizeof(etherbuf), ap);
   1051 	return etherbuf;
   1052 }
   1053 
   1054 char *
   1055 ether_snprintf(char *buf, size_t len, const u_char *ap)
   1056 {
   1057 	char *cp = buf;
   1058 	size_t i;
   1059 
   1060 	for (i = 0; i < len / 3; i++) {
   1061 		*cp++ = hexdigits[*ap >> 4];
   1062 		*cp++ = hexdigits[*ap++ & 0xf];
   1063 		*cp++ = ':';
   1064 	}
   1065 	*--cp = '\0';
   1066 	return buf;
   1067 }
   1068 
   1069 /*
   1070  * Perform common duties while attaching to interface list
   1071  */
   1072 void
   1073 ether_ifattach(struct ifnet *ifp, const u_int8_t *lla)
   1074 {
   1075 	struct ethercom *ec = (struct ethercom *)ifp;
   1076 
   1077 	ifp->if_type = IFT_ETHER;
   1078 	ifp->if_addrlen = ETHER_ADDR_LEN;
   1079 	ifp->if_hdrlen = ETHER_HDR_LEN;
   1080 	ifp->if_dlt = DLT_EN10MB;
   1081 	ifp->if_mtu = ETHERMTU;
   1082 	ifp->if_output = ether_output;
   1083 	ifp->if_input = ether_input;
   1084 	if (ifp->if_baudrate == 0)
   1085 		ifp->if_baudrate = IF_Mbps(10);		/* just a default */
   1086 
   1087 	if_alloc_sadl(ifp);
   1088 	memcpy(LLADDR(ifp->if_sadl), lla, ifp->if_addrlen);
   1089 
   1090 	LIST_INIT(&ec->ec_multiaddrs);
   1091 	ifp->if_broadcastaddr = etherbroadcastaddr;
   1092 #if NBPFILTER > 0
   1093 	bpfattach(ifp, DLT_EN10MB, sizeof(struct ether_header));
   1094 #endif
   1095 #ifdef MBUFTRACE
   1096 	strlcpy(ec->ec_tx_mowner.mo_name, ifp->if_xname,
   1097 	    sizeof(ec->ec_tx_mowner.mo_name));
   1098 	strlcpy(ec->ec_tx_mowner.mo_descr, "tx",
   1099 	    sizeof(ec->ec_tx_mowner.mo_descr));
   1100 	strlcpy(ec->ec_rx_mowner.mo_name, ifp->if_xname,
   1101 	    sizeof(ec->ec_rx_mowner.mo_name));
   1102 	strlcpy(ec->ec_rx_mowner.mo_descr, "rx",
   1103 	    sizeof(ec->ec_rx_mowner.mo_descr));
   1104 	MOWNER_ATTACH(&ec->ec_tx_mowner);
   1105 	MOWNER_ATTACH(&ec->ec_rx_mowner);
   1106 	ifp->if_mowner = &ec->ec_tx_mowner;
   1107 #endif
   1108 }
   1109 
   1110 void
   1111 ether_ifdetach(struct ifnet *ifp)
   1112 {
   1113 	struct ethercom *ec = (void *) ifp;
   1114 	struct ether_multi *enm;
   1115 	int s;
   1116 
   1117 #if NBRIDGE > 0
   1118 	if (ifp->if_bridge)
   1119 		bridge_ifdetach(ifp);
   1120 #endif
   1121 
   1122 #if NBPFILTER > 0
   1123 	bpfdetach(ifp);
   1124 #endif
   1125 
   1126 #if NVLAN > 0
   1127 	if (ec->ec_nvlans)
   1128 		vlan_ifdetach(ifp);
   1129 #endif
   1130 
   1131 	s = splnet();
   1132 	while ((enm = LIST_FIRST(&ec->ec_multiaddrs)) != NULL) {
   1133 		LIST_REMOVE(enm, enm_list);
   1134 		free(enm, M_IFMADDR);
   1135 		ec->ec_multicnt--;
   1136 	}
   1137 	splx(s);
   1138 
   1139 #if 0	/* done in if_detach() */
   1140 	if_free_sadl(ifp);
   1141 #endif
   1142 
   1143 	MOWNER_DETACH(&ec->ec_rx_mowner);
   1144 	MOWNER_DETACH(&ec->ec_tx_mowner);
   1145 }
   1146 
   1147 #if 0
   1148 /*
   1149  * This is for reference.  We have a table-driven version
   1150  * of the little-endian crc32 generator, which is faster
   1151  * than the double-loop.
   1152  */
   1153 u_int32_t
   1154 ether_crc32_le(const u_int8_t *buf, size_t len)
   1155 {
   1156 	u_int32_t c, crc, carry;
   1157 	size_t i, j;
   1158 
   1159 	crc = 0xffffffffU;	/* initial value */
   1160 
   1161 	for (i = 0; i < len; i++) {
   1162 		c = buf[i];
   1163 		for (j = 0; j < 8; j++) {
   1164 			carry = ((crc & 0x01) ? 1 : 0) ^ (c & 0x01);
   1165 			crc >>= 1;
   1166 			c >>= 1;
   1167 			if (carry)
   1168 				crc = (crc ^ ETHER_CRC_POLY_LE);
   1169 		}
   1170 	}
   1171 
   1172 	return (crc);
   1173 }
   1174 #else
   1175 u_int32_t
   1176 ether_crc32_le(const u_int8_t *buf, size_t len)
   1177 {
   1178 	static const u_int32_t crctab[] = {
   1179 		0x00000000, 0x1db71064, 0x3b6e20c8, 0x26d930ac,
   1180 		0x76dc4190, 0x6b6b51f4, 0x4db26158, 0x5005713c,
   1181 		0xedb88320, 0xf00f9344, 0xd6d6a3e8, 0xcb61b38c,
   1182 		0x9b64c2b0, 0x86d3d2d4, 0xa00ae278, 0xbdbdf21c
   1183 	};
   1184 	u_int32_t crc;
   1185 	size_t i;
   1186 
   1187 	crc = 0xffffffffU;	/* initial value */
   1188 
   1189 	for (i = 0; i < len; i++) {
   1190 		crc ^= buf[i];
   1191 		crc = (crc >> 4) ^ crctab[crc & 0xf];
   1192 		crc = (crc >> 4) ^ crctab[crc & 0xf];
   1193 	}
   1194 
   1195 	return (crc);
   1196 }
   1197 #endif
   1198 
   1199 u_int32_t
   1200 ether_crc32_be(const u_int8_t *buf, size_t len)
   1201 {
   1202 	u_int32_t c, crc, carry;
   1203 	size_t i, j;
   1204 
   1205 	crc = 0xffffffffU;	/* initial value */
   1206 
   1207 	for (i = 0; i < len; i++) {
   1208 		c = buf[i];
   1209 		for (j = 0; j < 8; j++) {
   1210 			carry = ((crc & 0x80000000U) ? 1 : 0) ^ (c & 0x01);
   1211 			crc <<= 1;
   1212 			c >>= 1;
   1213 			if (carry)
   1214 				crc = (crc ^ ETHER_CRC_POLY_BE) | carry;
   1215 		}
   1216 	}
   1217 
   1218 	return (crc);
   1219 }
   1220 
   1221 #ifdef INET
   1222 const uint8_t ether_ipmulticast_min[ETHER_ADDR_LEN] =
   1223     { 0x01, 0x00, 0x5e, 0x00, 0x00, 0x00 };
   1224 const uint8_t ether_ipmulticast_max[ETHER_ADDR_LEN] =
   1225     { 0x01, 0x00, 0x5e, 0x7f, 0xff, 0xff };
   1226 #endif
   1227 #ifdef INET6
   1228 const uint8_t ether_ip6multicast_min[ETHER_ADDR_LEN] =
   1229     { 0x33, 0x33, 0x00, 0x00, 0x00, 0x00 };
   1230 const uint8_t ether_ip6multicast_max[ETHER_ADDR_LEN] =
   1231     { 0x33, 0x33, 0xff, 0xff, 0xff, 0xff };
   1232 #endif
   1233 
   1234 /*
   1235  * Convert a sockaddr into an Ethernet address or range of Ethernet
   1236  * addresses.
   1237  */
   1238 int
   1239 ether_multiaddr(struct sockaddr *sa, u_int8_t addrlo[ETHER_ADDR_LEN],
   1240     u_int8_t addrhi[ETHER_ADDR_LEN])
   1241 {
   1242 #ifdef INET
   1243 	struct sockaddr_in *sin;
   1244 #endif /* INET */
   1245 #ifdef INET6
   1246 	struct sockaddr_in6 *sin6;
   1247 #endif /* INET6 */
   1248 
   1249 	switch (sa->sa_family) {
   1250 
   1251 	case AF_UNSPEC:
   1252 		bcopy(sa->sa_data, addrlo, ETHER_ADDR_LEN);
   1253 		bcopy(addrlo, addrhi, ETHER_ADDR_LEN);
   1254 		break;
   1255 
   1256 #ifdef INET
   1257 	case AF_INET:
   1258 		sin = satosin(sa);
   1259 		if (sin->sin_addr.s_addr == INADDR_ANY) {
   1260 			/*
   1261 			 * An IP address of INADDR_ANY means listen to
   1262 			 * or stop listening to all of the Ethernet
   1263 			 * multicast addresses used for IP.
   1264 			 * (This is for the sake of IP multicast routers.)
   1265 			 */
   1266 			bcopy(ether_ipmulticast_min, addrlo, ETHER_ADDR_LEN);
   1267 			bcopy(ether_ipmulticast_max, addrhi, ETHER_ADDR_LEN);
   1268 		}
   1269 		else {
   1270 			ETHER_MAP_IP_MULTICAST(&sin->sin_addr, addrlo);
   1271 			bcopy(addrlo, addrhi, ETHER_ADDR_LEN);
   1272 		}
   1273 		break;
   1274 #endif
   1275 #ifdef INET6
   1276 	case AF_INET6:
   1277 		sin6 = satosin6(sa);
   1278 		if (IN6_IS_ADDR_UNSPECIFIED(&sin6->sin6_addr)) {
   1279 			/*
   1280 			 * An IP6 address of 0 means listen to or stop
   1281 			 * listening to all of the Ethernet multicast
   1282 			 * address used for IP6.
   1283 			 * (This is used for multicast routers.)
   1284 			 */
   1285 			bcopy(ether_ip6multicast_min, addrlo, ETHER_ADDR_LEN);
   1286 			bcopy(ether_ip6multicast_max, addrhi, ETHER_ADDR_LEN);
   1287 		} else {
   1288 			ETHER_MAP_IPV6_MULTICAST(&sin6->sin6_addr, addrlo);
   1289 			bcopy(addrlo, addrhi, ETHER_ADDR_LEN);
   1290 		}
   1291 		break;
   1292 #endif
   1293 
   1294 	default:
   1295 		return (EAFNOSUPPORT);
   1296 	}
   1297 	return (0);
   1298 }
   1299 
   1300 /*
   1301  * Add an Ethernet multicast address or range of addresses to the list for a
   1302  * given interface.
   1303  */
   1304 int
   1305 ether_addmulti(struct ifreq *ifr, struct ethercom *ec)
   1306 {
   1307 	struct ether_multi *enm;
   1308 	u_char addrlo[ETHER_ADDR_LEN];
   1309 	u_char addrhi[ETHER_ADDR_LEN];
   1310 	int s = splnet(), error;
   1311 
   1312 	error = ether_multiaddr(&ifr->ifr_addr, addrlo, addrhi);
   1313 	if (error != 0) {
   1314 		splx(s);
   1315 		return (error);
   1316 	}
   1317 
   1318 	/*
   1319 	 * Verify that we have valid Ethernet multicast addresses.
   1320 	 */
   1321 	if ((addrlo[0] & 0x01) != 1 || (addrhi[0] & 0x01) != 1) {
   1322 		splx(s);
   1323 		return (EINVAL);
   1324 	}
   1325 	/*
   1326 	 * See if the address range is already in the list.
   1327 	 */
   1328 	ETHER_LOOKUP_MULTI(addrlo, addrhi, ec, enm);
   1329 	if (enm != NULL) {
   1330 		/*
   1331 		 * Found it; just increment the reference count.
   1332 		 */
   1333 		++enm->enm_refcount;
   1334 		splx(s);
   1335 		return (0);
   1336 	}
   1337 	/*
   1338 	 * New address or range; malloc a new multicast record
   1339 	 * and link it into the interface's multicast list.
   1340 	 */
   1341 	enm = (struct ether_multi *)malloc(sizeof(*enm), M_IFMADDR, M_NOWAIT);
   1342 	if (enm == NULL) {
   1343 		splx(s);
   1344 		return (ENOBUFS);
   1345 	}
   1346 	bcopy(addrlo, enm->enm_addrlo, 6);
   1347 	bcopy(addrhi, enm->enm_addrhi, 6);
   1348 	enm->enm_refcount = 1;
   1349 	LIST_INSERT_HEAD(&ec->ec_multiaddrs, enm, enm_list);
   1350 	ec->ec_multicnt++;
   1351 	splx(s);
   1352 	/*
   1353 	 * Return ENETRESET to inform the driver that the list has changed
   1354 	 * and its reception filter should be adjusted accordingly.
   1355 	 */
   1356 	return (ENETRESET);
   1357 }
   1358 
   1359 /*
   1360  * Delete a multicast address record.
   1361  */
   1362 int
   1363 ether_delmulti(struct ifreq *ifr, struct ethercom *ec)
   1364 {
   1365 	struct ether_multi *enm;
   1366 	u_char addrlo[ETHER_ADDR_LEN];
   1367 	u_char addrhi[ETHER_ADDR_LEN];
   1368 	int s = splnet(), error;
   1369 
   1370 	error = ether_multiaddr(&ifr->ifr_addr, addrlo, addrhi);
   1371 	if (error != 0) {
   1372 		splx(s);
   1373 		return (error);
   1374 	}
   1375 
   1376 	/*
   1377 	 * Look ur the address in our list.
   1378 	 */
   1379 	ETHER_LOOKUP_MULTI(addrlo, addrhi, ec, enm);
   1380 	if (enm == NULL) {
   1381 		splx(s);
   1382 		return (ENXIO);
   1383 	}
   1384 	if (--enm->enm_refcount != 0) {
   1385 		/*
   1386 		 * Still some claims to this record.
   1387 		 */
   1388 		splx(s);
   1389 		return (0);
   1390 	}
   1391 	/*
   1392 	 * No remaining claims to this record; unlink and free it.
   1393 	 */
   1394 	LIST_REMOVE(enm, enm_list);
   1395 	free(enm, M_IFMADDR);
   1396 	ec->ec_multicnt--;
   1397 	splx(s);
   1398 	/*
   1399 	 * Return ENETRESET to inform the driver that the list has changed
   1400 	 * and its reception filter should be adjusted accordingly.
   1401 	 */
   1402 	return (ENETRESET);
   1403 }
   1404 
   1405 /*
   1406  * Common ioctls for Ethernet interfaces.  Note, we must be
   1407  * called at splnet().
   1408  */
   1409 int
   1410 ether_ioctl(struct ifnet *ifp, u_long cmd, caddr_t data)
   1411 {
   1412 	struct ethercom *ec = (void *) ifp;
   1413 	struct ifreq *ifr = (struct ifreq *)data;
   1414 	struct ifaddr *ifa = (struct ifaddr *)data;
   1415 	int error = 0;
   1416 
   1417 	switch (cmd) {
   1418 	case SIOCSIFADDR:
   1419 		ifp->if_flags |= IFF_UP;
   1420 		switch (ifa->ifa_addr->sa_family) {
   1421 		case AF_LINK:
   1422 		    {
   1423 			struct sockaddr_dl *sdl =
   1424 			    (struct sockaddr_dl *) ifa->ifa_addr;
   1425 
   1426 			if (sdl->sdl_type != IFT_ETHER ||
   1427 			    sdl->sdl_alen != ifp->if_addrlen) {
   1428 				error = EINVAL;
   1429 				break;
   1430 			}
   1431 
   1432 			memcpy(LLADDR(ifp->if_sadl), LLADDR(sdl),
   1433 			    ifp->if_addrlen);
   1434 
   1435 			/* Set new address. */
   1436 			error = (*ifp->if_init)(ifp);
   1437 			break;
   1438 		    }
   1439 #ifdef INET
   1440 		case AF_INET:
   1441 			if ((ifp->if_flags & IFF_RUNNING) == 0 &&
   1442 			    (error = (*ifp->if_init)(ifp)) != 0)
   1443 				break;
   1444 			arp_ifinit(ifp, ifa);
   1445 			break;
   1446 #endif /* INET */
   1447 		default:
   1448 			if ((ifp->if_flags & IFF_RUNNING) == 0)
   1449 				error = (*ifp->if_init)(ifp);
   1450 			break;
   1451 		}
   1452 		break;
   1453 
   1454 	case SIOCGIFADDR:
   1455 		memcpy(((struct sockaddr *)&ifr->ifr_data)->sa_data,
   1456 		    LLADDR(ifp->if_sadl), ETHER_ADDR_LEN);
   1457 		break;
   1458 
   1459 	case SIOCSIFMTU:
   1460 	    {
   1461 		int maxmtu;
   1462 
   1463 		if (ec->ec_capabilities & ETHERCAP_JUMBO_MTU)
   1464 			maxmtu = ETHERMTU_JUMBO;
   1465 		else
   1466 			maxmtu = ETHERMTU;
   1467 
   1468 		if (ifr->ifr_mtu < ETHERMIN || ifr->ifr_mtu > maxmtu)
   1469 			error = EINVAL;
   1470 		else {
   1471 			ifp->if_mtu = ifr->ifr_mtu;
   1472 
   1473 			/* Make sure the device notices the MTU change. */
   1474 			if (ifp->if_flags & IFF_UP)
   1475 				error = (*ifp->if_init)(ifp);
   1476 		}
   1477 		break;
   1478 	    }
   1479 
   1480 	case SIOCSIFFLAGS:
   1481 		if ((ifp->if_flags & (IFF_UP|IFF_RUNNING)) == IFF_RUNNING) {
   1482 			/*
   1483 			 * If interface is marked down and it is running,
   1484 			 * then stop and disable it.
   1485 			 */
   1486 			(*ifp->if_stop)(ifp, 1);
   1487 		} else if ((ifp->if_flags & (IFF_UP|IFF_RUNNING)) == IFF_UP) {
   1488 			/*
   1489 			 * If interface is marked up and it is stopped, then
   1490 			 * start it.
   1491 			 */
   1492 			error = (*ifp->if_init)(ifp);
   1493 		} else if ((ifp->if_flags & IFF_UP) != 0) {
   1494 			/*
   1495 			 * Reset the interface to pick up changes in any other
   1496 			 * flags that affect the hardware state.
   1497 			 */
   1498 			error = (*ifp->if_init)(ifp);
   1499 		}
   1500 		break;
   1501 
   1502 	case SIOCADDMULTI:
   1503 		error = ether_addmulti(ifr, ec);
   1504 		break;
   1505 
   1506 	case SIOCDELMULTI:
   1507 		error = ether_delmulti(ifr, ec);
   1508 		break;
   1509 
   1510 	default:
   1511 		error = ENOTTY;
   1512 	}
   1513 
   1514 	return (error);
   1515 }
   1516