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if_ethersubr.c revision 1.31
      1 /*	$NetBSD: if_ethersubr.c,v 1.31 1998/04/30 00:05:41 thorpej Exp $	*/
      2 
      3 /*
      4  * Copyright (c) 1982, 1989, 1993
      5  *	The Regents of the University of California.  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. All advertising materials mentioning features or use of this software
     16  *    must display the following acknowledgement:
     17  *	This product includes software developed by the University of
     18  *	California, Berkeley and its contributors.
     19  * 4. Neither the name of the University nor the names of its contributors
     20  *    may be used to endorse or promote products derived from this software
     21  *    without specific prior written permission.
     22  *
     23  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
     24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
     27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     33  * SUCH DAMAGE.
     34  *
     35  *	@(#)if_ethersubr.c	8.2 (Berkeley) 4/4/96
     36  */
     37 
     38 #include "opt_gateway.h"
     39 
     40 #include <sys/param.h>
     41 #include <sys/systm.h>
     42 #include <sys/kernel.h>
     43 #include <sys/malloc.h>
     44 #include <sys/mbuf.h>
     45 #include <sys/protosw.h>
     46 #include <sys/socket.h>
     47 #include <sys/ioctl.h>
     48 #include <sys/errno.h>
     49 #include <sys/syslog.h>
     50 
     51 #include <machine/cpu.h>
     52 
     53 #include <net/if.h>
     54 #include <net/netisr.h>
     55 #include <net/route.h>
     56 #include <net/if_llc.h>
     57 #include <net/if_dl.h>
     58 #include <net/if_types.h>
     59 
     60 #include <net/if_ether.h>
     61 
     62 #include <netinet/in.h>
     63 #ifdef INET
     64 #include <netinet/in_var.h>
     65 #endif
     66 #include <netinet/if_inarp.h>
     67 
     68 #ifdef NS
     69 #include <netns/ns.h>
     70 #include <netns/ns_if.h>
     71 #endif
     72 
     73 #ifdef ISO
     74 #include <netiso/argo_debug.h>
     75 #include <netiso/iso.h>
     76 #include <netiso/iso_var.h>
     77 #include <netiso/iso_snpac.h>
     78 #endif
     79 
     80 #ifdef LLC
     81 #include <netccitt/dll.h>
     82 #include <netccitt/llc_var.h>
     83 #endif
     84 
     85 #if defined(LLC) && defined(CCITT)
     86 extern struct ifqueue pkintrq;
     87 #endif
     88 
     89 #ifdef NETATALK
     90 #include <netatalk/at.h>
     91 #include <netatalk/at_var.h>
     92 #include <netatalk/at_extern.h>
     93 
     94 #define llc_snap_org_code llc_un.type_snap.org_code
     95 #define llc_snap_ether_type llc_un.type_snap.ether_type
     96 
     97 extern u_char	at_org_code[3];
     98 extern u_char	aarp_org_code[3];
     99 #endif /* NETATALK */
    100 
    101 u_char	etherbroadcastaddr[6] = { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff };
    102 #define senderr(e) { error = (e); goto bad;}
    103 
    104 #define SIN(x) ((struct sockaddr_in *)x)
    105 
    106 /*
    107  * Ethernet output routine.
    108  * Encapsulate a packet of type family for the local net.
    109  * Assumes that ifp is actually pointer to ethercom structure.
    110  */
    111 int
    112 ether_output(ifp, m0, dst, rt0)
    113 	struct ifnet *ifp;
    114 	struct mbuf *m0;
    115 	struct sockaddr *dst;
    116 	struct rtentry *rt0;
    117 {
    118 	u_int16_t etype;
    119 	int s, error = 0, hdrcmplt = 0;
    120  	u_char esrc[6], edst[6];
    121 	struct mbuf *m = m0;
    122 	struct rtentry *rt;
    123 	struct mbuf *mcopy = (struct mbuf *)0;
    124 	struct ether_header *eh;
    125 #ifdef INET
    126 	struct arphdr *ah;
    127 #endif /* INET */
    128 #ifdef NETATALK
    129 	struct at_ifaddr *aa;
    130 #endif /* NETATALK */
    131 
    132 	if ((ifp->if_flags & (IFF_UP|IFF_RUNNING)) != (IFF_UP|IFF_RUNNING))
    133 		senderr(ENETDOWN);
    134 	ifp->if_lastchange = time;
    135 	if ((rt = rt0) != NULL) {
    136 		if ((rt->rt_flags & RTF_UP) == 0) {
    137 			if ((rt0 = rt = rtalloc1(dst, 1)) != NULL) {
    138 				rt->rt_refcnt--;
    139 				if (rt->rt_ifp != ifp)
    140 					return (*rt->rt_ifp->if_output)
    141 							(ifp, m0, dst, rt);
    142 			} else
    143 				senderr(EHOSTUNREACH);
    144 		}
    145 		if ((rt->rt_flags & RTF_GATEWAY) && dst->sa_family != AF_NS) {
    146 			if (rt->rt_gwroute == 0)
    147 				goto lookup;
    148 			if (((rt = rt->rt_gwroute)->rt_flags & RTF_UP) == 0) {
    149 				rtfree(rt); rt = rt0;
    150 			lookup: rt->rt_gwroute = rtalloc1(rt->rt_gateway, 1);
    151 				if ((rt = rt->rt_gwroute) == 0)
    152 					senderr(EHOSTUNREACH);
    153 				/* the "G" test below also prevents rt == rt0 */
    154 				if ((rt->rt_flags & RTF_GATEWAY) ||
    155 				    (rt->rt_ifp != ifp)) {
    156 					rt->rt_refcnt--;
    157 					rt0->rt_gwroute = 0;
    158 					senderr(EHOSTUNREACH);
    159 				}
    160 			}
    161 		}
    162 		if (rt->rt_flags & RTF_REJECT)
    163 			if (rt->rt_rmx.rmx_expire == 0 ||
    164 			    time.tv_sec < rt->rt_rmx.rmx_expire)
    165 				senderr(rt == rt0 ? EHOSTDOWN : EHOSTUNREACH);
    166 	}
    167 	switch (dst->sa_family) {
    168 
    169 #ifdef INET
    170 	case AF_INET:
    171 		if (m->m_flags & M_BCAST)
    172                 	bcopy((caddr_t)etherbroadcastaddr, (caddr_t)edst,
    173 				sizeof(edst));
    174 
    175 		else if (m->m_flags & M_MCAST) {
    176 			ETHER_MAP_IP_MULTICAST(&SIN(dst)->sin_addr,
    177 			    (caddr_t)edst)
    178 
    179 		} else if (!arpresolve(ifp, rt, m, dst, edst))
    180 			return (0);	/* if not yet resolved */
    181 		/* If broadcasting on a simplex interface, loopback a copy */
    182 		if ((m->m_flags & M_BCAST) && (ifp->if_flags & IFF_SIMPLEX))
    183 			mcopy = m_copy(m, 0, (int)M_COPYALL);
    184 		etype = htons(ETHERTYPE_IP);
    185 		break;
    186 
    187 	case AF_ARP:
    188 		ah = mtod(m, struct arphdr *);
    189 		if (m->m_flags & M_BCAST)
    190                 	bcopy((caddr_t)etherbroadcastaddr, (caddr_t)edst,
    191 				sizeof(edst));
    192 		else
    193 			bcopy((caddr_t)ar_tha(ah),
    194 				(caddr_t)edst, sizeof(edst));
    195 
    196 		ah->ar_hrd = htons(ARPHRD_ETHER);
    197 
    198 		switch(ntohs(ah->ar_op)) {
    199 		case ARPOP_REVREQUEST:
    200 		case ARPOP_REVREPLY:
    201 			etype = htons(ETHERTYPE_REVARP);
    202 			break;
    203 
    204 		case ARPOP_REQUEST:
    205 		case ARPOP_REPLY:
    206 		default:
    207 			etype = htons(ETHERTYPE_ARP);
    208 		}
    209 
    210 		break;
    211 #endif
    212 #ifdef NETATALK
    213     case AF_APPLETALK:
    214 		if (!aarpresolve(ifp, m, (struct sockaddr_at *)dst, edst)) {
    215 #ifdef NETATALKDEBUG
    216 			printf("aarpresolv failed\n");
    217 #endif /* NETATALKDEBUG */
    218 			return (0);
    219 		}
    220 		/*
    221 		 * ifaddr is the first thing in at_ifaddr
    222 		 */
    223 		aa = (struct at_ifaddr *) at_ifawithnet(
    224 		    (struct sockaddr_at *)dst, ifp);
    225 		if (aa == NULL)
    226 		    goto bad;
    227 
    228 		/*
    229 		 * In the phase 2 case, we need to prepend an mbuf for the
    230 		 * llc header.  Since we must preserve the value of m,
    231 		 * which is passed to us by value, we m_copy() the first
    232 		 * mbuf, and use it for our llc header.
    233 		 */
    234 		if (aa->aa_flags & AFA_PHASE2) {
    235 			struct llc llc;
    236 
    237 			M_PREPEND(m, sizeof(struct llc), M_WAIT);
    238 			llc.llc_dsap = llc.llc_ssap = LLC_SNAP_LSAP;
    239 			llc.llc_control = LLC_UI;
    240 			bcopy(at_org_code, llc.llc_snap_org_code,
    241 			    sizeof(llc.llc_snap_org_code));
    242 			llc.llc_snap_ether_type = htons(ETHERTYPE_AT);
    243 			bcopy(&llc, mtod(m, caddr_t), sizeof(struct llc));
    244 			etype = htons(m->m_pkthdr.len);
    245 		} else {
    246 			etype = htons(ETHERTYPE_AT);
    247 		}
    248 		break;
    249 #endif /* NETATALK */
    250 #ifdef NS
    251 	case AF_NS:
    252 		etype = htons(ETHERTYPE_NS);
    253  		bcopy((caddr_t)&(((struct sockaddr_ns *)dst)->sns_addr.x_host),
    254 		    (caddr_t)edst, sizeof (edst));
    255 		if (!bcmp((caddr_t)edst, (caddr_t)&ns_thishost, sizeof(edst)))
    256 			return (looutput(ifp, m, dst, rt));
    257 		/* If broadcasting on a simplex interface, loopback a copy */
    258 		if ((m->m_flags & M_BCAST) && (ifp->if_flags & IFF_SIMPLEX))
    259 			mcopy = m_copy(m, 0, (int)M_COPYALL);
    260 		break;
    261 #endif
    262 #ifdef	ISO
    263 	case AF_ISO: {
    264 		int	snpalen;
    265 		struct	llc *l;
    266 		struct sockaddr_dl *sdl;
    267 
    268 		if (rt && (sdl = (struct sockaddr_dl *)rt->rt_gateway) &&
    269 		    sdl->sdl_family == AF_LINK && sdl->sdl_alen > 0) {
    270 			bcopy(LLADDR(sdl), (caddr_t)edst, sizeof(edst));
    271 		} else {
    272 			error = iso_snparesolve(ifp, (struct sockaddr_iso *)dst,
    273 						(char *)edst, &snpalen);
    274 			if (error)
    275 				goto bad; /* Not Resolved */
    276 		}
    277 		/* If broadcasting on a simplex interface, loopback a copy */
    278 		if (*edst & 1)
    279 			m->m_flags |= (M_BCAST|M_MCAST);
    280 		if ((m->m_flags & M_BCAST) && (ifp->if_flags & IFF_SIMPLEX) &&
    281 		    (mcopy = m_copy(m, 0, (int)M_COPYALL))) {
    282 			M_PREPEND(mcopy, sizeof (*eh), M_DONTWAIT);
    283 			if (mcopy) {
    284 				eh = mtod(mcopy, struct ether_header *);
    285 				bcopy((caddr_t)edst,
    286 				      (caddr_t)eh->ether_dhost, sizeof (edst));
    287 				bcopy(LLADDR(ifp->if_sadl),
    288 				      (caddr_t)eh->ether_shost, sizeof (edst));
    289 			}
    290 		}
    291 		M_PREPEND(m, 3, M_DONTWAIT);
    292 		if (m == NULL)
    293 			return (0);
    294 		etype = htons(m->m_pkthdr.len);
    295 		l = mtod(m, struct llc *);
    296 		l->llc_dsap = l->llc_ssap = LLC_ISO_LSAP;
    297 		l->llc_control = LLC_UI;
    298 #ifdef ARGO_DEBUG
    299 		if (argo_debug[D_ETHER]) {
    300 			int i;
    301 			printf("unoutput: sending pkt to: ");
    302 			for (i=0; i<6; i++)
    303 				printf("%x ", edst[i] & 0xff);
    304 			printf("\n");
    305 		}
    306 #endif
    307 		} break;
    308 #endif /* ISO */
    309 #ifdef	LLC
    310 /*	case AF_NSAP: */
    311 	case AF_CCITT: {
    312 		struct sockaddr_dl *sdl =
    313 			(struct sockaddr_dl *) rt -> rt_gateway;
    314 
    315 		if (sdl && sdl->sdl_family == AF_LINK
    316 		    && sdl->sdl_alen > 0) {
    317 			bcopy(LLADDR(sdl), (char *)edst,
    318 				sizeof(edst));
    319 		} else goto bad; /* Not a link interface ? Funny ... */
    320 		if ((ifp->if_flags & IFF_SIMPLEX) && (*edst & 1) &&
    321 		    (mcopy = m_copy(m, 0, (int)M_COPYALL))) {
    322 			M_PREPEND(mcopy, sizeof (*eh), M_DONTWAIT);
    323 			if (mcopy) {
    324 				eh = mtod(mcopy, struct ether_header *);
    325 				bcopy((caddr_t)edst,
    326 				      (caddr_t)eh->ether_dhost, sizeof (edst));
    327 				bcopy(LLADDR(ifp->if_sadl),
    328 				      (caddr_t)eh->ether_shost, sizeof (edst));
    329 			}
    330 		}
    331 		etype = htons(m->m_pkthdr.len);
    332 #ifdef LLC_DEBUG
    333 		{
    334 			int i;
    335 			struct llc *l = mtod(m, struct llc *);
    336 
    337 			printf("ether_output: sending LLC2 pkt to: ");
    338 			for (i=0; i<6; i++)
    339 				printf("%x ", edst[i] & 0xff);
    340 			printf(" len 0x%x dsap 0x%x ssap 0x%x control 0x%x\n",
    341 			    m->m_pkthdr.len, l->llc_dsap & 0xff, l->llc_ssap &0xff,
    342 			    l->llc_control & 0xff);
    343 
    344 		}
    345 #endif /* LLC_DEBUG */
    346 		} break;
    347 #endif /* LLC */
    348 
    349 	case pseudo_AF_HDRCMPLT:
    350 		hdrcmplt = 1;
    351 		eh = (struct ether_header *)dst->sa_data;
    352 		bcopy((caddr_t)eh->ether_shost, (caddr_t)esrc, sizeof (esrc));
    353 		/* FALLTHROUGH */
    354 
    355 	case AF_UNSPEC:
    356 		eh = (struct ether_header *)dst->sa_data;
    357  		bcopy((caddr_t)eh->ether_dhost, (caddr_t)edst, sizeof (edst));
    358 		/* AF_UNSPEC doesn't swap the byte order of the ether_type. */
    359 		etype = eh->ether_type;
    360 		break;
    361 
    362 	default:
    363 		printf("%s: can't handle af%d\n", ifp->if_xname,
    364 			dst->sa_family);
    365 		senderr(EAFNOSUPPORT);
    366 	}
    367 
    368 	if (mcopy)
    369 		(void) looutput(ifp, mcopy, dst, rt);
    370 
    371 	/*
    372 	 * Add local net header.  If no space in first mbuf,
    373 	 * allocate another.
    374 	 */
    375 	M_PREPEND(m, sizeof (struct ether_header), M_DONTWAIT);
    376 	if (m == 0)
    377 		senderr(ENOBUFS);
    378 	eh = mtod(m, struct ether_header *);
    379 	bcopy((caddr_t)&etype,(caddr_t)&eh->ether_type,
    380 		sizeof(eh->ether_type));
    381  	bcopy((caddr_t)edst, (caddr_t)eh->ether_dhost, sizeof (edst));
    382 	if (hdrcmplt)
    383 		bcopy((caddr_t)esrc, (caddr_t)eh->ether_shost,
    384 		    sizeof(eh->ether_shost));
    385 	else
    386 	 	bcopy(LLADDR(ifp->if_sadl), (caddr_t)eh->ether_shost,
    387 		    sizeof(eh->ether_shost));
    388 	s = splimp();
    389 	/*
    390 	 * Queue message on interface, and start output if interface
    391 	 * not yet active.
    392 	 */
    393 	if (IF_QFULL(&ifp->if_snd)) {
    394 		IF_DROP(&ifp->if_snd);
    395 		splx(s);
    396 		senderr(ENOBUFS);
    397 	}
    398 	ifp->if_obytes += m->m_pkthdr.len;
    399 	IF_ENQUEUE(&ifp->if_snd, m);
    400 	if ((ifp->if_flags & IFF_OACTIVE) == 0)
    401 		(*ifp->if_start)(ifp);
    402 	splx(s);
    403 	if (m->m_flags & M_MCAST)
    404 		ifp->if_omcasts++;
    405 	return (error);
    406 
    407 bad:
    408 	if (m)
    409 		m_freem(m);
    410 	return (error);
    411 }
    412 
    413 /*
    414  * Process a received Ethernet packet;
    415  * the packet is in the mbuf chain m without
    416  * the ether header, which is provided separately.
    417  */
    418 void
    419 ether_input(ifp, eh, m)
    420 	struct ifnet *ifp;
    421 	struct ether_header *eh;
    422 	struct mbuf *m;
    423 {
    424 	struct ifqueue *inq;
    425 	u_int16_t etype;
    426 	int s;
    427 #if defined (ISO) || defined (LLC) || defined(NETATALK)
    428 	struct llc *l;
    429 #endif
    430 
    431 	if ((ifp->if_flags & IFF_UP) == 0) {
    432 		m_freem(m);
    433 		return;
    434 	}
    435 	ifp->if_lastchange = time;
    436 	ifp->if_ibytes += m->m_pkthdr.len + sizeof (*eh);
    437 	if (eh->ether_dhost[0] & 1) {
    438 		if (bcmp((caddr_t)etherbroadcastaddr, (caddr_t)eh->ether_dhost,
    439 		    sizeof(etherbroadcastaddr)) == 0)
    440 			m->m_flags |= M_BCAST;
    441 		else
    442 			m->m_flags |= M_MCAST;
    443 	}
    444 	if (m->m_flags & (M_BCAST|M_MCAST))
    445 		ifp->if_imcasts++;
    446 
    447 	etype = ntohs(eh->ether_type);
    448 	switch (etype) {
    449 #ifdef INET
    450 	case ETHERTYPE_IP:
    451 #ifdef GATEWAY
    452 		if (ipflow_fastforward(m))
    453 			return;
    454 #endif
    455 		schednetisr(NETISR_IP);
    456 		inq = &ipintrq;
    457 		break;
    458 
    459 	case ETHERTYPE_ARP:
    460 		schednetisr(NETISR_ARP);
    461 		inq = &arpintrq;
    462 		break;
    463 
    464 	case ETHERTYPE_REVARP:
    465 		revarpinput(m);	/* XXX queue? */
    466 		return;
    467 #endif
    468 #ifdef NS
    469 	case ETHERTYPE_NS:
    470 		schednetisr(NETISR_NS);
    471 		inq = &nsintrq;
    472 		break;
    473 
    474 #endif
    475 #ifdef NETATALK
    476         case ETHERTYPE_AT:
    477                 schednetisr(NETISR_ATALK);
    478                 inq = &atintrq1;
    479                 break;
    480         case ETHERTYPE_AARP:
    481 		/* probably this should be done with a NETISR as well */
    482                 aarpinput(ifp, m); /* XXX */
    483                 return;
    484 #endif /* NETATALK */
    485 	default:
    486 #if defined (ISO) || defined (LLC) || defined (NETATALK)
    487 		if (etype > ETHERMTU)
    488 			goto dropanyway;
    489 		l = mtod(m, struct llc *);
    490 		switch (l->llc_dsap) {
    491 #ifdef NETATALK
    492 		case LLC_SNAP_LSAP:
    493 			switch (l->llc_control) {
    494 			case LLC_UI:
    495 				if (l->llc_ssap != LLC_SNAP_LSAP) {
    496 					goto dropanyway;
    497 				}
    498 
    499 				if (Bcmp(&(l->llc_snap_org_code)[0],
    500 				    at_org_code, sizeof(at_org_code)) == 0 &&
    501 				    ntohs(l->llc_snap_ether_type) ==
    502 				    ETHERTYPE_AT) {
    503 					inq = &atintrq2;
    504 					m_adj(m, sizeof(struct llc));
    505 					schednetisr(NETISR_ATALK);
    506 					break;
    507 				}
    508 
    509 				if (Bcmp(&(l->llc_snap_org_code)[0],
    510 				    aarp_org_code,
    511 				    sizeof(aarp_org_code)) == 0 &&
    512 				    ntohs(l->llc_snap_ether_type) ==
    513 				    ETHERTYPE_AARP) {
    514 					m_adj( m, sizeof(struct llc));
    515 					aarpinput(ifp, m); /* XXX */
    516 				    return;
    517 				}
    518 
    519 			default:
    520 				goto dropanyway;
    521 			}
    522 			break;
    523 #endif /* NETATALK */
    524 #ifdef	ISO
    525 		case LLC_ISO_LSAP:
    526 			switch (l->llc_control) {
    527 			case LLC_UI:
    528 				/* LLC_UI_P forbidden in class 1 service */
    529 				if ((l->llc_dsap == LLC_ISO_LSAP) &&
    530 				    (l->llc_ssap == LLC_ISO_LSAP)) {
    531 					/* LSAP for ISO */
    532 					if (m->m_pkthdr.len > etype)
    533 						m_adj(m, etype - m->m_pkthdr.len);
    534 					m->m_data += 3;		/* XXX */
    535 					m->m_len -= 3;		/* XXX */
    536 					m->m_pkthdr.len -= 3;	/* XXX */
    537 					M_PREPEND(m, sizeof *eh, M_DONTWAIT);
    538 					if (m == 0)
    539 						return;
    540 					*mtod(m, struct ether_header *) = *eh;
    541 #ifdef ARGO_DEBUG
    542 					if (argo_debug[D_ETHER])
    543 						printf("clnp packet");
    544 #endif
    545 					schednetisr(NETISR_ISO);
    546 					inq = &clnlintrq;
    547 					break;
    548 				}
    549 				goto dropanyway;
    550 
    551 			case LLC_XID:
    552 			case LLC_XID_P:
    553 				if(m->m_len < 6)
    554 					goto dropanyway;
    555 				l->llc_window = 0;
    556 				l->llc_fid = 9;
    557 				l->llc_class = 1;
    558 				l->llc_dsap = l->llc_ssap = 0;
    559 				/* Fall through to */
    560 			case LLC_TEST:
    561 			case LLC_TEST_P:
    562 			{
    563 				struct sockaddr sa;
    564 				struct ether_header *eh2;
    565 				int i;
    566 				u_char c = l->llc_dsap;
    567 
    568 				l->llc_dsap = l->llc_ssap;
    569 				l->llc_ssap = c;
    570 				if (m->m_flags & (M_BCAST | M_MCAST))
    571 					bcopy(LLADDR(ifp->if_sadl),
    572 					      (caddr_t)eh->ether_dhost, 6);
    573 				sa.sa_family = AF_UNSPEC;
    574 				sa.sa_len = sizeof(sa);
    575 				eh2 = (struct ether_header *)sa.sa_data;
    576 				for (i = 0; i < 6; i++) {
    577 					eh2->ether_shost[i] = c =
    578 					    eh->ether_dhost[i];
    579 					eh2->ether_dhost[i] =
    580 					    eh->ether_dhost[i] =
    581 					    eh->ether_shost[i];
    582 					eh->ether_shost[i] = c;
    583 				}
    584 				ifp->if_output(ifp, m, &sa, NULL);
    585 				return;
    586 			}
    587 			default:
    588 				m_freem(m);
    589 				return;
    590 			}
    591 			break;
    592 #endif /* ISO */
    593 #ifdef LLC
    594 		case LLC_X25_LSAP:
    595 		{
    596 			if (m->m_pkthdr.len > etype)
    597 				m_adj(m, etype - m->m_pkthdr.len);
    598 			M_PREPEND(m, sizeof(struct sdl_hdr) , M_DONTWAIT);
    599 			if (m == 0)
    600 				return;
    601 			if ( !sdl_sethdrif(ifp, eh->ether_shost, LLC_X25_LSAP,
    602 					    eh->ether_dhost, LLC_X25_LSAP, 6,
    603 					    mtod(m, struct sdl_hdr *)))
    604 				panic("ETHER cons addr failure");
    605 			mtod(m, struct sdl_hdr *)->sdlhdr_len = etype;
    606 #ifdef LLC_DEBUG
    607 				printf("llc packet\n");
    608 #endif /* LLC_DEBUG */
    609 			schednetisr(NETISR_CCITT);
    610 			inq = &llcintrq;
    611 			break;
    612 		}
    613 #endif /* LLC */
    614 		dropanyway:
    615 		default:
    616 			m_freem(m);
    617 			return;
    618 		}
    619 #else /* ISO || LLC  || NETATALK*/
    620 	    m_freem(m);
    621 	    return;
    622 #endif /* ISO || LLC || NETATALK*/
    623 	}
    624 
    625 	s = splimp();
    626 	if (IF_QFULL(inq)) {
    627 		IF_DROP(inq);
    628 		m_freem(m);
    629 	} else
    630 		IF_ENQUEUE(inq, m);
    631 	splx(s);
    632 }
    633 
    634 /*
    635  * Convert Ethernet address to printable (loggable) representation.
    636  */
    637 static char digits[] = "0123456789abcdef";
    638 char *
    639 ether_sprintf(ap)
    640 	u_char *ap;
    641 {
    642 	static char etherbuf[18];
    643 	char *cp = etherbuf;
    644 	int i;
    645 
    646 	for (i = 0; i < 6; i++) {
    647 		*cp++ = digits[*ap >> 4];
    648 		*cp++ = digits[*ap++ & 0xf];
    649 		*cp++ = ':';
    650 	}
    651 	*--cp = 0;
    652 	return (etherbuf);
    653 }
    654 
    655 /*
    656  * Perform common duties while attaching to interface list
    657  */
    658 void
    659 ether_ifattach(ifp, lla)
    660 	struct ifnet *ifp;
    661 	u_int8_t * lla;
    662 {
    663 	struct sockaddr_dl *sdl;
    664 
    665 	ifp->if_type = IFT_ETHER;
    666 	ifp->if_addrlen = 6;
    667 	ifp->if_hdrlen = 14;
    668 	ifp->if_mtu = ETHERMTU;
    669 	ifp->if_output = ether_output;
    670 	if ((sdl = ifp->if_sadl) &&
    671 	    sdl->sdl_family == AF_LINK) {
    672 		sdl->sdl_type = IFT_ETHER;
    673 		sdl->sdl_alen = ifp->if_addrlen;
    674 		bcopy((caddr_t)lla, LLADDR(sdl), ifp->if_addrlen);
    675 	}
    676 	LIST_INIT(&((struct ethercom *)ifp)->ec_multiaddrs);
    677 	ifp->if_broadcastaddr = etherbroadcastaddr;
    678 }
    679 
    680 u_char	ether_ipmulticast_min[6] = { 0x01, 0x00, 0x5e, 0x00, 0x00, 0x00 };
    681 u_char	ether_ipmulticast_max[6] = { 0x01, 0x00, 0x5e, 0x7f, 0xff, 0xff };
    682 /*
    683  * Add an Ethernet multicast address or range of addresses to the list for a
    684  * given interface.
    685  */
    686 int
    687 ether_addmulti(ifr, ec)
    688 	struct ifreq *ifr;
    689 	struct ethercom *ec;
    690 {
    691 	struct ether_multi *enm;
    692 #ifdef INET
    693 	struct sockaddr_in *sin;
    694 #endif /* INET */
    695 	u_char addrlo[6];
    696 	u_char addrhi[6];
    697 	int s = splimp();
    698 
    699 	switch (ifr->ifr_addr.sa_family) {
    700 
    701 	case AF_UNSPEC:
    702 		bcopy(ifr->ifr_addr.sa_data, addrlo, 6);
    703 		bcopy(addrlo, addrhi, 6);
    704 		break;
    705 
    706 #ifdef INET
    707 	case AF_INET:
    708 		sin = (struct sockaddr_in *)&(ifr->ifr_addr);
    709 		if (sin->sin_addr.s_addr == INADDR_ANY) {
    710 			/*
    711 			 * An IP address of INADDR_ANY means listen to all
    712 			 * of the Ethernet multicast addresses used for IP.
    713 			 * (This is for the sake of IP multicast routers.)
    714 			 */
    715 			bcopy(ether_ipmulticast_min, addrlo, 6);
    716 			bcopy(ether_ipmulticast_max, addrhi, 6);
    717 		}
    718 		else {
    719 			ETHER_MAP_IP_MULTICAST(&sin->sin_addr, addrlo);
    720 			bcopy(addrlo, addrhi, 6);
    721 		}
    722 		break;
    723 #endif
    724 
    725 	default:
    726 		splx(s);
    727 		return (EAFNOSUPPORT);
    728 	}
    729 
    730 	/*
    731 	 * Verify that we have valid Ethernet multicast addresses.
    732 	 */
    733 	if ((addrlo[0] & 0x01) != 1 || (addrhi[0] & 0x01) != 1) {
    734 		splx(s);
    735 		return (EINVAL);
    736 	}
    737 	/*
    738 	 * See if the address range is already in the list.
    739 	 */
    740 	ETHER_LOOKUP_MULTI(addrlo, addrhi, ec, enm);
    741 	if (enm != NULL) {
    742 		/*
    743 		 * Found it; just increment the reference count.
    744 		 */
    745 		++enm->enm_refcount;
    746 		splx(s);
    747 		return (0);
    748 	}
    749 	/*
    750 	 * New address or range; malloc a new multicast record
    751 	 * and link it into the interface's multicast list.
    752 	 */
    753 	enm = (struct ether_multi *)malloc(sizeof(*enm), M_IFMADDR, M_NOWAIT);
    754 	if (enm == NULL) {
    755 		splx(s);
    756 		return (ENOBUFS);
    757 	}
    758 	bcopy(addrlo, enm->enm_addrlo, 6);
    759 	bcopy(addrhi, enm->enm_addrhi, 6);
    760 	enm->enm_ec = ec;
    761 	enm->enm_refcount = 1;
    762 	LIST_INSERT_HEAD(&ec->ec_multiaddrs, enm, enm_list);
    763 	ec->ec_multicnt++;
    764 	splx(s);
    765 	/*
    766 	 * Return ENETRESET to inform the driver that the list has changed
    767 	 * and its reception filter should be adjusted accordingly.
    768 	 */
    769 	return (ENETRESET);
    770 }
    771 
    772 /*
    773  * Delete a multicast address record.
    774  */
    775 int
    776 ether_delmulti(ifr, ec)
    777 	struct ifreq *ifr;
    778 	struct ethercom *ec;
    779 {
    780 	struct ether_multi *enm;
    781 #ifdef INET
    782 	struct sockaddr_in *sin;
    783 #endif /* INET */
    784 	u_char addrlo[6];
    785 	u_char addrhi[6];
    786 	int s = splimp();
    787 
    788 	switch (ifr->ifr_addr.sa_family) {
    789 
    790 	case AF_UNSPEC:
    791 		bcopy(ifr->ifr_addr.sa_data, addrlo, 6);
    792 		bcopy(addrlo, addrhi, 6);
    793 		break;
    794 
    795 #ifdef INET
    796 	case AF_INET:
    797 		sin = (struct sockaddr_in *)&(ifr->ifr_addr);
    798 		if (sin->sin_addr.s_addr == INADDR_ANY) {
    799 			/*
    800 			 * An IP address of INADDR_ANY means stop listening
    801 			 * to the range of Ethernet multicast addresses used
    802 			 * for IP.
    803 			 */
    804 			bcopy(ether_ipmulticast_min, addrlo, 6);
    805 			bcopy(ether_ipmulticast_max, addrhi, 6);
    806 		}
    807 		else {
    808 			ETHER_MAP_IP_MULTICAST(&sin->sin_addr, addrlo);
    809 			bcopy(addrlo, addrhi, 6);
    810 		}
    811 		break;
    812 #endif
    813 
    814 	default:
    815 		splx(s);
    816 		return (EAFNOSUPPORT);
    817 	}
    818 
    819 	/*
    820 	 * Look up the address in our list.
    821 	 */
    822 	ETHER_LOOKUP_MULTI(addrlo, addrhi, ec, enm);
    823 	if (enm == NULL) {
    824 		splx(s);
    825 		return (ENXIO);
    826 	}
    827 	if (--enm->enm_refcount != 0) {
    828 		/*
    829 		 * Still some claims to this record.
    830 		 */
    831 		splx(s);
    832 		return (0);
    833 	}
    834 	/*
    835 	 * No remaining claims to this record; unlink and free it.
    836 	 */
    837 	LIST_REMOVE(enm, enm_list);
    838 	free(enm, M_IFMADDR);
    839 	ec->ec_multicnt--;
    840 	splx(s);
    841 	/*
    842 	 * Return ENETRESET to inform the driver that the list has changed
    843 	 * and its reception filter should be adjusted accordingly.
    844 	 */
    845 	return (ENETRESET);
    846 }
    847