xref: /dragonfly/sys/net/vlan/if_vlan.c (revision 2d8a3be7)
1 /*
2  * Copyright 1998 Massachusetts Institute of Technology
3  *
4  * Permission to use, copy, modify, and distribute this software and
5  * its documentation for any purpose and without fee is hereby
6  * granted, provided that both the above copyright notice and this
7  * permission notice appear in all copies, that both the above
8  * copyright notice and this permission notice appear in all
9  * supporting documentation, and that the name of M.I.T. not be used
10  * in advertising or publicity pertaining to distribution of the
11  * software without specific, written prior permission.  M.I.T. makes
12  * no representations about the suitability of this software for any
13  * purpose.  It is provided "as is" without express or implied
14  * warranty.
15  *
16  * THIS SOFTWARE IS PROVIDED BY M.I.T. ``AS IS''.  M.I.T. DISCLAIMS
17  * ALL EXPRESS OR IMPLIED WARRANTIES WITH REGARD TO THIS SOFTWARE,
18  * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
19  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT
20  * SHALL M.I.T. BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
21  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
22  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
23  * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
24  * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
25  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
26  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  *
29  * $FreeBSD: src/sys/net/if_vlan.c,v 1.15.2.13 2003/02/14 22:25:58 fenner Exp $
30  * $DragonFly: src/sys/net/vlan/if_vlan.c,v 1.4 2003/08/07 21:17:30 dillon Exp $
31  */
32 
33 /*
34  * if_vlan.c - pseudo-device driver for IEEE 802.1Q virtual LANs.
35  * Might be extended some day to also handle IEEE 802.1p priority
36  * tagging.  This is sort of sneaky in the implementation, since
37  * we need to pretend to be enough of an Ethernet implementation
38  * to make arp work.  The way we do this is by telling everyone
39  * that we are an Ethernet, and then catch the packets that
40  * ether_output() left on our output queue queue when it calls
41  * if_start(), rewrite them for use by the real outgoing interface,
42  * and ask it to send them.
43  *
44  *
45  * XXX It's incorrect to assume that we must always kludge up
46  * headers on the physical device's behalf: some devices support
47  * VLAN tag insertion and extraction in firmware. For these cases,
48  * one can change the behavior of the vlan interface by setting
49  * the LINK0 flag on it (that is setting the vlan interface's LINK0
50  * flag, _not_ the parent's LINK0 flag; we try to leave the parent
51  * alone). If the interface has the LINK0 flag set, then it will
52  * not modify the ethernet header on output, because the parent
53  * can do that for itself. On input, the parent can call vlan_input_tag()
54  * directly in order to supply us with an incoming mbuf and the vlan
55  * tag value that goes with it.
56  */
57 
58 #ifndef NVLAN
59 #include "use_vlan.h"
60 #endif
61 #include "opt_inet.h"
62 
63 #include <sys/param.h>
64 #include <sys/kernel.h>
65 #include <sys/malloc.h>
66 #include <sys/mbuf.h>
67 #include <sys/module.h>
68 #include <sys/queue.h>
69 #include <sys/socket.h>
70 #include <sys/sockio.h>
71 #include <sys/sysctl.h>
72 #include <sys/systm.h>
73 #include <machine/bus.h>	/* XXX: Shouldn't really be required! */
74 #include <sys/rman.h>
75 
76 #include <net/bpf.h>
77 #include <net/ethernet.h>
78 #include <net/if.h>
79 #include <net/if_arp.h>
80 #include <net/if_dl.h>
81 #include <net/if_types.h>
82 #include "if_vlan_var.h"
83 
84 #ifdef INET
85 #include <netinet/in.h>
86 #include <netinet/if_ether.h>
87 #endif
88 
89 #define VLANNAME	"vlan"
90 #define VLAN_MAXUNIT	0x7fff	/* ifp->if_unit is only 15 bits */
91 
92 SYSCTL_DECL(_net_link);
93 SYSCTL_NODE(_net_link, IFT_L2VLAN, vlan, CTLFLAG_RW, 0, "IEEE 802.1Q VLAN");
94 SYSCTL_NODE(_net_link_vlan, PF_LINK, link, CTLFLAG_RW, 0, "for consistency");
95 
96 static MALLOC_DEFINE(M_VLAN, "vlan", "802.1Q Virtual LAN Interface");
97 static struct rman vlanunits[1];
98 static LIST_HEAD(, ifvlan) ifv_list;
99 
100 static	int vlan_clone_create(struct if_clone *, int *);
101 static	void vlan_clone_destroy(struct ifnet *);
102 static	void vlan_start(struct ifnet *ifp);
103 static	void vlan_ifinit(void *foo);
104 static	int vlan_input(struct ether_header *eh, struct mbuf *m);
105 static	int vlan_input_tag(struct ether_header *eh, struct mbuf *m,
106 		u_int16_t t);
107 static	int vlan_ioctl(struct ifnet *ifp, u_long cmd, caddr_t addr);
108 static	int vlan_setmulti(struct ifnet *ifp);
109 static	int vlan_unconfig(struct ifnet *ifp);
110 static	int vlan_config(struct ifvlan *ifv, struct ifnet *p);
111 
112 struct if_clone vlan_cloner =
113     IF_CLONE_INITIALIZER("vlan", vlan_clone_create, vlan_clone_destroy);
114 
115 /*
116  * Program our multicast filter. What we're actually doing is
117  * programming the multicast filter of the parent. This has the
118  * side effect of causing the parent interface to receive multicast
119  * traffic that it doesn't really want, which ends up being discarded
120  * later by the upper protocol layers. Unfortunately, there's no way
121  * to avoid this: there really is only one physical interface.
122  */
123 static int
124 vlan_setmulti(struct ifnet *ifp)
125 {
126 	struct ifnet		*ifp_p;
127 	struct ifmultiaddr	*ifma, *rifma = NULL;
128 	struct ifvlan		*sc;
129 	struct vlan_mc_entry	*mc = NULL;
130 	struct sockaddr_dl	sdl;
131 	int			error;
132 
133 	/* Find the parent. */
134 	sc = ifp->if_softc;
135 	ifp_p = sc->ifv_p;
136 
137 	/*
138 	 * If we don't have a parent, just remember the membership for
139 	 * when we do.
140 	 */
141 	if (ifp_p == NULL)
142 		return(0);
143 
144 	bzero((char *)&sdl, sizeof sdl);
145 	sdl.sdl_len = sizeof sdl;
146 	sdl.sdl_family = AF_LINK;
147 	sdl.sdl_index = ifp_p->if_index;
148 	sdl.sdl_type = IFT_ETHER;
149 	sdl.sdl_alen = ETHER_ADDR_LEN;
150 
151 	/* First, remove any existing filter entries. */
152 	while(SLIST_FIRST(&sc->vlan_mc_listhead) != NULL) {
153 		mc = SLIST_FIRST(&sc->vlan_mc_listhead);
154 		bcopy((char *)&mc->mc_addr, LLADDR(&sdl), ETHER_ADDR_LEN);
155 		error = if_delmulti(ifp_p, (struct sockaddr *)&sdl);
156 		if (error)
157 			return(error);
158 		SLIST_REMOVE_HEAD(&sc->vlan_mc_listhead, mc_entries);
159 		free(mc, M_VLAN);
160 	}
161 
162 	/* Now program new ones. */
163 	LIST_FOREACH(ifma, &ifp->if_multiaddrs, ifma_link) {
164 		if (ifma->ifma_addr->sa_family != AF_LINK)
165 			continue;
166 		mc = malloc(sizeof(struct vlan_mc_entry), M_VLAN, M_WAITOK);
167 		bcopy(LLADDR((struct sockaddr_dl *)ifma->ifma_addr),
168 		    (char *)&mc->mc_addr, ETHER_ADDR_LEN);
169 		SLIST_INSERT_HEAD(&sc->vlan_mc_listhead, mc, mc_entries);
170 		bcopy(LLADDR((struct sockaddr_dl *)ifma->ifma_addr),
171 		    LLADDR(&sdl), ETHER_ADDR_LEN);
172 		error = if_addmulti(ifp_p, (struct sockaddr *)&sdl, &rifma);
173 		if (error)
174 			return(error);
175 	}
176 
177 	return(0);
178 }
179 
180 static int
181 vlan_modevent(module_t mod, int type, void *data)
182 {
183 	int i;
184 	int err;
185 
186 	switch (type) {
187 	case MOD_LOAD:
188 		vlanunits->rm_type = RMAN_ARRAY;
189 		vlanunits->rm_descr = "configurable if_vlan units";
190 		err = rman_init(vlanunits);
191 		if (err != 0)
192 			return (err);
193 		err = rman_manage_region(vlanunits, 0, VLAN_MAXUNIT);
194 		if (err != 0) {
195 			printf("%s: vlanunits: rman_manage_region: Failed %d\n",
196 			    VLANNAME, err);
197 			rman_fini(vlanunits);
198 			return (err);
199 		}
200 		LIST_INIT(&ifv_list);
201 		vlan_input_p = vlan_input;
202 		vlan_input_tag_p = vlan_input_tag;
203 		if_clone_attach(&vlan_cloner);
204 		for(i = 0; i < NVLAN; i ++) {
205 			err = vlan_clone_create(&vlan_cloner, &i);
206 			KASSERT(err == 0,
207 			    ("Unexpected error creating initial VLANs"));
208 		}
209 		break;
210 	case MOD_UNLOAD:
211 		if_clone_detach(&vlan_cloner);
212 		vlan_input_p = NULL;
213 		vlan_input_tag_p = NULL;
214 		while (!LIST_EMPTY(&ifv_list))
215 			vlan_clone_destroy(&LIST_FIRST(&ifv_list)->ifv_if);
216 		err = rman_fini(vlanunits);
217 		if (err != 0)
218 			 return (err);
219 		break;
220 	}
221 	return 0;
222 }
223 
224 static moduledata_t vlan_mod = {
225 	"if_vlan",
226 	vlan_modevent,
227 	0
228 };
229 
230 DECLARE_MODULE(if_vlan, vlan_mod, SI_SUB_PSEUDO, SI_ORDER_ANY);
231 
232 static int
233 vlan_clone_create(struct if_clone *ifc, int *unit)
234 {
235 	struct resource *r;
236 	struct ifvlan *ifv;
237 	struct ifnet *ifp;
238 	int s;
239 
240 	if (*unit > VLAN_MAXUNIT)
241 		return (ENXIO);
242 
243 	if (*unit < 0) {
244 		r  = rman_reserve_resource(vlanunits, 0, VLAN_MAXUNIT, 1,
245 		    RF_ALLOCATED | RF_ACTIVE, NULL);
246 		if (r == NULL)
247 			return (ENOSPC);
248 		*unit = rman_get_start(r);
249 	} else {
250 		r  = rman_reserve_resource(vlanunits, *unit, *unit, 1,
251 		    RF_ALLOCATED | RF_ACTIVE, NULL);
252 		if (r == NULL)
253 			return (EEXIST);
254 	}
255 
256 	ifv = malloc(sizeof(struct ifvlan), M_VLAN, M_WAITOK);
257 	memset(ifv, 0, sizeof(struct ifvlan));
258 	ifp = &ifv->ifv_if;
259 	SLIST_INIT(&ifv->vlan_mc_listhead);
260 
261 	s = splnet();
262 	LIST_INSERT_HEAD(&ifv_list, ifv, ifv_list);
263 	splx(s);
264 
265 	ifp->if_softc = ifv;
266 	ifp->if_name = "vlan";
267 	ifp->if_unit = *unit;
268 	ifv->r_unit = r;
269 	/* NB: flags are not set here */
270 	ifp->if_linkmib = &ifv->ifv_mib;
271 	ifp->if_linkmiblen = sizeof ifv->ifv_mib;
272 	/* NB: mtu is not set here */
273 
274 	ifp->if_init = vlan_ifinit;
275 	ifp->if_start = vlan_start;
276 	ifp->if_ioctl = vlan_ioctl;
277 	ifp->if_output = ether_output;
278 	ifp->if_snd.ifq_maxlen = ifqmaxlen;
279 	ether_ifattach(ifp, ETHER_BPF_SUPPORTED);
280 	/* Now undo some of the damage... */
281 	ifp->if_data.ifi_type = IFT_L2VLAN;
282 	ifp->if_data.ifi_hdrlen = EVL_ENCAPLEN;
283 
284 	return (0);
285 }
286 
287 static void
288 vlan_clone_destroy(struct ifnet *ifp)
289 {
290 	struct ifvlan *ifv = ifp->if_softc;
291 	int s;
292 	int err;
293 
294 	s = splnet();
295 	LIST_REMOVE(ifv, ifv_list);
296 	vlan_unconfig(ifp);
297 	splx(s);
298 
299 	ether_ifdetach(ifp, ETHER_BPF_SUPPORTED);
300 
301 	err = rman_release_resource(ifv->r_unit);
302 	KASSERT(err == 0, ("Unexpected error freeing resource"));
303 	free(ifv, M_VLAN);
304 }
305 
306 static void
307 vlan_ifinit(void *foo)
308 {
309 	return;
310 }
311 
312 static void
313 vlan_start(struct ifnet *ifp)
314 {
315 	struct ifvlan *ifv;
316 	struct ifnet *p;
317 	struct ether_vlan_header *evl;
318 	struct mbuf *m;
319 
320 	ifv = ifp->if_softc;
321 	p = ifv->ifv_p;
322 
323 	ifp->if_flags |= IFF_OACTIVE;
324 	for (;;) {
325 		IF_DEQUEUE(&ifp->if_snd, m);
326 		if (m == 0)
327 			break;
328 		if (ifp->if_bpf)
329 			bpf_mtap(ifp, m);
330 
331 		/*
332 		 * Do not run parent's if_start() if the parent is not up,
333 		 * or parent's driver will cause a system crash.
334 		 */
335 		if ((p->if_flags & (IFF_UP | IFF_RUNNING)) !=
336 					(IFF_UP | IFF_RUNNING)) {
337 			m_freem(m);
338 			ifp->if_data.ifi_collisions++;
339 			continue;
340 		}
341 
342 		/*
343 		 * If the LINK0 flag is set, it means the underlying interface
344 		 * can do VLAN tag insertion itself and doesn't require us to
345 	 	 * create a special header for it. In this case, we just pass
346 		 * the packet along. However, we need some way to tell the
347 		 * interface where the packet came from so that it knows how
348 		 * to find the VLAN tag to use, so we set the rcvif in the
349 		 * mbuf header to our ifnet.
350 		 *
351 		 * Note: we also set the M_PROTO1 flag in the mbuf to let
352 		 * the parent driver know that the rcvif pointer is really
353 		 * valid. We need to do this because sometimes mbufs will
354 		 * be allocated by other parts of the system that contain
355 		 * garbage in the rcvif pointer. Using the M_PROTO1 flag
356 		 * lets the driver perform a proper sanity check and avoid
357 		 * following potentially bogus rcvif pointers off into
358 		 * never-never land.
359 		 */
360 		if (ifp->if_flags & IFF_LINK0) {
361 			m->m_pkthdr.rcvif = ifp;
362 			m->m_flags |= M_PROTO1;
363 		} else {
364 			M_PREPEND(m, EVL_ENCAPLEN, M_DONTWAIT);
365 			if (m == NULL) {
366 				printf("vlan%d: M_PREPEND failed", ifp->if_unit);
367 				ifp->if_ierrors++;
368 				continue;
369 			}
370 			/* M_PREPEND takes care of m_len, m_pkthdr.len for us */
371 
372 			m = m_pullup(m, ETHER_HDR_LEN + EVL_ENCAPLEN);
373 			if (m == NULL) {
374 				printf("vlan%d: m_pullup failed", ifp->if_unit);
375 				ifp->if_ierrors++;
376 				continue;
377 			}
378 
379 			/*
380 			 * Transform the Ethernet header into an Ethernet header
381 			 * with 802.1Q encapsulation.
382 			 */
383 			bcopy(mtod(m, char *) + EVL_ENCAPLEN, mtod(m, char *),
384 			      sizeof(struct ether_header));
385 			evl = mtod(m, struct ether_vlan_header *);
386 			evl->evl_proto = evl->evl_encap_proto;
387 			evl->evl_encap_proto = htons(ETHERTYPE_VLAN);
388 			evl->evl_tag = htons(ifv->ifv_tag);
389 #ifdef DEBUG
390 			printf("vlan_start: %*D\n", sizeof *evl,
391 			    (unsigned char *)evl, ":");
392 #endif
393 		}
394 
395 		/*
396 		 * Send it, precisely as ether_output() would have.
397 		 * We are already running at splimp.
398 		 */
399 		if (IF_QFULL(&p->if_snd)) {
400 			IF_DROP(&p->if_snd);
401 				/* XXX stats */
402 			ifp->if_oerrors++;
403 			m_freem(m);
404 			continue;
405 		}
406 		IF_ENQUEUE(&p->if_snd, m);
407 		ifp->if_opackets++;
408 		p->if_obytes += m->m_pkthdr.len;
409 		if (m->m_flags & M_MCAST)
410 			p->if_omcasts++;
411 		if ((p->if_flags & IFF_OACTIVE) == 0)
412 			p->if_start(p);
413 	}
414 	ifp->if_flags &= ~IFF_OACTIVE;
415 
416 	return;
417 }
418 
419 static int
420 vlan_input_tag(struct ether_header *eh, struct mbuf *m, u_int16_t t)
421 {
422 	struct ifvlan *ifv;
423 
424 	/*
425 	 * Fake up a header and send the packet to the physical interface's
426 	 * bpf tap if active.
427 	 */
428 	if (m->m_pkthdr.rcvif->if_bpf != NULL) {
429 		struct m_hdr mh;
430 		struct ether_vlan_header evh;
431 
432 		bcopy(eh, &evh, 2*ETHER_ADDR_LEN);
433 		evh.evl_encap_proto = htons(ETHERTYPE_VLAN);
434 		evh.evl_tag = htons(t);
435 		evh.evl_proto = eh->ether_type;
436 
437 		/* This kludge is OK; BPF treats the "mbuf" as read-only */
438 		mh.mh_next = m;
439 		mh.mh_data = (char *)&evh;
440 		mh.mh_len = ETHER_HDR_LEN + EVL_ENCAPLEN;
441 		bpf_mtap(m->m_pkthdr.rcvif, (struct mbuf *)&mh);
442 	}
443 
444 	for (ifv = LIST_FIRST(&ifv_list); ifv != NULL;
445 	    ifv = LIST_NEXT(ifv, ifv_list)) {
446 		if (m->m_pkthdr.rcvif == ifv->ifv_p
447 		    && ifv->ifv_tag == t)
448 			break;
449 	}
450 
451 	if (ifv == NULL || (ifv->ifv_if.if_flags & IFF_UP) == 0) {
452 		m_freem(m);
453 		return -1;	/* So the parent can take note */
454 	}
455 
456 	/*
457 	 * Having found a valid vlan interface corresponding to
458 	 * the given source interface and vlan tag, run the
459 	 * the real packet through ether_input().
460 	 */
461 	m->m_pkthdr.rcvif = &ifv->ifv_if;
462 
463 	ifv->ifv_if.if_ipackets++;
464 	ether_input(&ifv->ifv_if, eh, m);
465 	return 0;
466 }
467 
468 static int
469 vlan_input(struct ether_header *eh, struct mbuf *m)
470 {
471 	struct ifvlan *ifv;
472 
473 	for (ifv = LIST_FIRST(&ifv_list); ifv != NULL;
474 	    ifv = LIST_NEXT(ifv, ifv_list)) {
475 		if (m->m_pkthdr.rcvif == ifv->ifv_p
476 		    && (EVL_VLANOFTAG(ntohs(*mtod(m, u_int16_t *)))
477 			== ifv->ifv_tag))
478 			break;
479 	}
480 
481 	if (ifv == NULL || (ifv->ifv_if.if_flags & IFF_UP) == 0) {
482 		m->m_pkthdr.rcvif->if_noproto++;
483 		m_freem(m);
484 		return -1;	/* so ether_input can take note */
485 	}
486 
487 	/*
488 	 * Having found a valid vlan interface corresponding to
489 	 * the given source interface and vlan tag, remove the
490 	 * encapsulation, and run the real packet through
491 	 * ether_input() a second time (it had better be
492 	 * reentrant!).
493 	 */
494 	m->m_pkthdr.rcvif = &ifv->ifv_if;
495 	eh->ether_type = mtod(m, u_int16_t *)[1];
496 	m->m_data += EVL_ENCAPLEN;
497 	m->m_len -= EVL_ENCAPLEN;
498 	m->m_pkthdr.len -= EVL_ENCAPLEN;
499 
500 	ifv->ifv_if.if_ipackets++;
501 	ether_input(&ifv->ifv_if, eh, m);
502 	return 0;
503 }
504 
505 static int
506 vlan_config(struct ifvlan *ifv, struct ifnet *p)
507 {
508 	struct ifaddr *ifa1, *ifa2;
509 	struct sockaddr_dl *sdl1, *sdl2;
510 
511 	if (p->if_data.ifi_type != IFT_ETHER)
512 		return EPROTONOSUPPORT;
513 	if (ifv->ifv_p)
514 		return EBUSY;
515 	ifv->ifv_p = p;
516 	if (p->if_data.ifi_hdrlen == sizeof(struct ether_vlan_header))
517 		ifv->ifv_if.if_mtu = p->if_mtu;
518 	else
519 		ifv->ifv_if.if_mtu = p->if_data.ifi_mtu - EVL_ENCAPLEN;
520 
521 	/*
522 	 * Copy only a selected subset of flags from the parent.
523 	 * Other flags are none of our business.
524 	 */
525 	ifv->ifv_if.if_flags = (p->if_flags &
526 	    (IFF_BROADCAST | IFF_MULTICAST | IFF_SIMPLEX | IFF_POINTOPOINT));
527 
528 	/*
529 	 * Set up our ``Ethernet address'' to reflect the underlying
530 	 * physical interface's.
531 	 */
532 	ifa1 = ifnet_addrs[ifv->ifv_if.if_index - 1];
533 	ifa2 = ifnet_addrs[p->if_index - 1];
534 	sdl1 = (struct sockaddr_dl *)ifa1->ifa_addr;
535 	sdl2 = (struct sockaddr_dl *)ifa2->ifa_addr;
536 	sdl1->sdl_type = IFT_ETHER;
537 	sdl1->sdl_alen = ETHER_ADDR_LEN;
538 	bcopy(LLADDR(sdl2), LLADDR(sdl1), ETHER_ADDR_LEN);
539 	bcopy(LLADDR(sdl2), ifv->ifv_ac.ac_enaddr, ETHER_ADDR_LEN);
540 
541 	/*
542 	 * Configure multicast addresses that may already be
543 	 * joined on the vlan device.
544 	 */
545 	(void)vlan_setmulti(&ifv->ifv_if);
546 
547 	return 0;
548 }
549 
550 static int
551 vlan_unconfig(struct ifnet *ifp)
552 {
553 	struct ifaddr *ifa;
554 	struct sockaddr_dl *sdl;
555 	struct vlan_mc_entry *mc;
556 	struct ifvlan *ifv;
557 	struct ifnet *p;
558 	int error;
559 
560 	ifv = ifp->if_softc;
561 	p = ifv->ifv_p;
562 
563 	if (p) {
564 		struct sockaddr_dl sdl;
565 
566 		/*
567 		 * Since the interface is being unconfigured, we need to
568 		 * empty the list of multicast groups that we may have joined
569 		 * while we were alive from the parent's list.
570 		 */
571 		bzero((char *)&sdl, sizeof sdl);
572 		sdl.sdl_len = sizeof sdl;
573 		sdl.sdl_family = AF_LINK;
574 		sdl.sdl_index = p->if_index;
575 		sdl.sdl_type = IFT_ETHER;
576 		sdl.sdl_alen = ETHER_ADDR_LEN;
577 
578 		while(SLIST_FIRST(&ifv->vlan_mc_listhead) != NULL) {
579 			mc = SLIST_FIRST(&ifv->vlan_mc_listhead);
580 			bcopy((char *)&mc->mc_addr, LLADDR(&sdl), ETHER_ADDR_LEN);
581 			error = if_delmulti(p, (struct sockaddr *)&sdl);
582 			if (error)
583 				return(error);
584 			SLIST_REMOVE_HEAD(&ifv->vlan_mc_listhead, mc_entries);
585 			free(mc, M_VLAN);
586 		}
587 	}
588 
589 	/* Disconnect from parent. */
590 	ifv->ifv_p = NULL;
591 	ifv->ifv_if.if_mtu = ETHERMTU;
592 
593 	/* Clear our MAC address. */
594 	ifa = ifnet_addrs[ifv->ifv_if.if_index - 1];
595 	sdl = (struct sockaddr_dl *)ifa->ifa_addr;
596 	sdl->sdl_type = IFT_ETHER;
597 	sdl->sdl_alen = ETHER_ADDR_LEN;
598 	bzero(LLADDR(sdl), ETHER_ADDR_LEN);
599 	bzero(ifv->ifv_ac.ac_enaddr, ETHER_ADDR_LEN);
600 
601 	return 0;
602 }
603 
604 static int
605 vlan_ioctl(struct ifnet *ifp, u_long cmd, caddr_t data)
606 {
607 	struct ifaddr *ifa;
608 	struct ifnet *p;
609 	struct ifreq *ifr;
610 	struct ifvlan *ifv;
611 	struct vlanreq vlr;
612 	int error = 0;
613 
614 	ifr = (struct ifreq *)data;
615 	ifa = (struct ifaddr *)data;
616 	ifv = ifp->if_softc;
617 
618 	switch (cmd) {
619 	case SIOCSIFADDR:
620 		ifp->if_flags |= IFF_UP;
621 
622 		switch (ifa->ifa_addr->sa_family) {
623 #ifdef INET
624 		case AF_INET:
625 			arp_ifinit(&ifv->ifv_if, ifa);
626 			break;
627 #endif
628 		default:
629 			break;
630 		}
631 		break;
632 
633 	case SIOCGIFADDR:
634 		{
635 			struct sockaddr *sa;
636 
637 			sa = (struct sockaddr *) &ifr->ifr_data;
638 			bcopy(((struct arpcom *)ifp->if_softc)->ac_enaddr,
639 			      (caddr_t) sa->sa_data, ETHER_ADDR_LEN);
640 		}
641 		break;
642 
643 	case SIOCGIFMEDIA:
644 		if (ifv->ifv_p != NULL) {
645 			error = (ifv->ifv_p->if_ioctl)(ifv->ifv_p, SIOCGIFMEDIA, data);
646 			/* Limit the result to the parent's current config. */
647 			if (error == 0) {
648 				struct ifmediareq *ifmr;
649 
650 				ifmr = (struct ifmediareq *) data;
651 				if (ifmr->ifm_count >= 1 && ifmr->ifm_ulist) {
652 					ifmr->ifm_count = 1;
653 					error = copyout(&ifmr->ifm_current,
654 						ifmr->ifm_ulist,
655 						sizeof(int));
656 				}
657 			}
658 		} else
659 			error = EINVAL;
660 		break;
661 
662 	case SIOCSIFMEDIA:
663 		error = EINVAL;
664 		break;
665 
666 	case SIOCSIFMTU:
667 		/*
668 		 * Set the interface MTU.
669 		 * This is bogus. The underlying interface might support
670 	 	 * jumbo frames.
671 		 */
672 		if (ifr->ifr_mtu > ETHERMTU) {
673 			error = EINVAL;
674 		} else {
675 			ifp->if_mtu = ifr->ifr_mtu;
676 		}
677 		break;
678 
679 	case SIOCSETVLAN:
680 		error = copyin(ifr->ifr_data, &vlr, sizeof vlr);
681 		if (error)
682 			break;
683 		if (vlr.vlr_parent[0] == '\0') {
684 			vlan_unconfig(ifp);
685 			if (ifp->if_flags & IFF_UP) {
686 				int s = splimp();
687 				if_down(ifp);
688 				splx(s);
689 			}
690 			ifp->if_flags &= ~IFF_RUNNING;
691 			break;
692 		}
693 		p = ifunit(vlr.vlr_parent);
694 		if (p == 0) {
695 			error = ENOENT;
696 			break;
697 		}
698 		error = vlan_config(ifv, p);
699 		if (error)
700 			break;
701 		ifv->ifv_tag = vlr.vlr_tag;
702 		ifp->if_flags |= IFF_RUNNING;
703 		break;
704 
705 	case SIOCGETVLAN:
706 		bzero(&vlr, sizeof vlr);
707 		if (ifv->ifv_p) {
708 			snprintf(vlr.vlr_parent, sizeof(vlr.vlr_parent),
709 			    "%s%d", ifv->ifv_p->if_name, ifv->ifv_p->if_unit);
710 			vlr.vlr_tag = ifv->ifv_tag;
711 		}
712 		error = copyout(&vlr, ifr->ifr_data, sizeof vlr);
713 		break;
714 
715 	case SIOCSIFFLAGS:
716 		/*
717 		 * We don't support promiscuous mode
718 		 * right now because it would require help from the
719 		 * underlying drivers, which hasn't been implemented.
720 		 */
721 		if (ifr->ifr_flags & (IFF_PROMISC)) {
722 			ifp->if_flags &= ~(IFF_PROMISC);
723 			error = EINVAL;
724 		}
725 		break;
726 	case SIOCADDMULTI:
727 	case SIOCDELMULTI:
728 		error = vlan_setmulti(ifp);
729 		break;
730 	default:
731 		error = EINVAL;
732 	}
733 	return error;
734 }
735