xref: /netbsd-src/sys/net/if_vlan.c (revision b8ecfcfef0e343ad71faea7a54fb5fcb42ad4e27)
1 /*	$NetBSD: if_vlan.c,v 1.78 2014/10/11 10:27:31 ozaki-r Exp $	*/
2 
3 /*-
4  * Copyright (c) 2000, 2001 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Andrew Doran, and by Jason R. Thorpe of Zembu Labs, Inc.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29  * POSSIBILITY OF SUCH DAMAGE.
30  */
31 
32 /*
33  * Copyright 1998 Massachusetts Institute of Technology
34  *
35  * Permission to use, copy, modify, and distribute this software and
36  * its documentation for any purpose and without fee is hereby
37  * granted, provided that both the above copyright notice and this
38  * permission notice appear in all copies, that both the above
39  * copyright notice and this permission notice appear in all
40  * supporting documentation, and that the name of M.I.T. not be used
41  * in advertising or publicity pertaining to distribution of the
42  * software without specific, written prior permission.  M.I.T. makes
43  * no representations about the suitability of this software for any
44  * purpose.  It is provided "as is" without express or implied
45  * warranty.
46  *
47  * THIS SOFTWARE IS PROVIDED BY M.I.T. ``AS IS''.  M.I.T. DISCLAIMS
48  * ALL EXPRESS OR IMPLIED WARRANTIES WITH REGARD TO THIS SOFTWARE,
49  * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
50  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT
51  * SHALL M.I.T. BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
52  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
53  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
54  * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
55  * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
56  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
57  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
58  * SUCH DAMAGE.
59  *
60  * from FreeBSD: if_vlan.c,v 1.16 2000/03/26 15:21:40 charnier Exp
61  * via OpenBSD: if_vlan.c,v 1.4 2000/05/15 19:15:00 chris Exp
62  */
63 
64 /*
65  * if_vlan.c - pseudo-device driver for IEEE 802.1Q virtual LANs.  Might be
66  * extended some day to also handle IEEE 802.1P priority tagging.  This is
67  * sort of sneaky in the implementation, since we need to pretend to be
68  * enough of an Ethernet implementation to make ARP work.  The way we do
69  * this is by telling everyone that we are an Ethernet interface, and then
70  * catch the packets that ether_output() left on our output queue when it
71  * calls if_start(), rewrite them for use by the real outgoing interface,
72  * and ask it to send them.
73  *
74  * TODO:
75  *
76  *	- Need some way to notify vlan interfaces when the parent
77  *	  interface changes MTU.
78  */
79 
80 #include <sys/cdefs.h>
81 __KERNEL_RCSID(0, "$NetBSD: if_vlan.c,v 1.78 2014/10/11 10:27:31 ozaki-r Exp $");
82 
83 #include "opt_inet.h"
84 
85 #include <sys/param.h>
86 #include <sys/kernel.h>
87 #include <sys/mbuf.h>
88 #include <sys/queue.h>
89 #include <sys/socket.h>
90 #include <sys/sockio.h>
91 #include <sys/systm.h>
92 #include <sys/proc.h>
93 #include <sys/kauth.h>
94 #include <sys/mutex.h>
95 
96 #include <net/bpf.h>
97 #include <net/if.h>
98 #include <net/if_dl.h>
99 #include <net/if_types.h>
100 #include <net/if_ether.h>
101 #include <net/if_vlanvar.h>
102 
103 #ifdef INET
104 #include <netinet/in.h>
105 #include <netinet/if_inarp.h>
106 #endif
107 #ifdef INET6
108 #include <netinet6/in6_ifattach.h>
109 #endif
110 
111 struct vlan_mc_entry {
112 	LIST_ENTRY(vlan_mc_entry)	mc_entries;
113 	/*
114 	 * A key to identify this entry.  The mc_addr below can't be
115 	 * used since multiple sockaddr may mapped into the same
116 	 * ether_multi (e.g., AF_UNSPEC).
117 	 */
118 	union {
119 		struct ether_multi	*mcu_enm;
120 	} mc_u;
121 	struct sockaddr_storage		mc_addr;
122 };
123 
124 #define	mc_enm		mc_u.mcu_enm
125 
126 struct ifvlan {
127 	union {
128 		struct ethercom ifvu_ec;
129 	} ifv_u;
130 	struct ifnet *ifv_p;	/* parent interface of this vlan */
131 	struct ifv_linkmib {
132 		const struct vlan_multisw *ifvm_msw;
133 		int	ifvm_encaplen;	/* encapsulation length */
134 		int	ifvm_mtufudge;	/* MTU fudged by this much */
135 		int	ifvm_mintu;	/* min transmission unit */
136 		uint16_t ifvm_proto;	/* encapsulation ethertype */
137 		uint16_t ifvm_tag;	/* tag to apply on packets */
138 	} ifv_mib;
139 	LIST_HEAD(__vlan_mchead, vlan_mc_entry) ifv_mc_listhead;
140 	LIST_ENTRY(ifvlan) ifv_list;
141 	int ifv_flags;
142 };
143 
144 #define	IFVF_PROMISC	0x01		/* promiscuous mode enabled */
145 
146 #define	ifv_ec		ifv_u.ifvu_ec
147 
148 #define	ifv_if		ifv_ec.ec_if
149 
150 #define	ifv_msw		ifv_mib.ifvm_msw
151 #define	ifv_encaplen	ifv_mib.ifvm_encaplen
152 #define	ifv_mtufudge	ifv_mib.ifvm_mtufudge
153 #define	ifv_mintu	ifv_mib.ifvm_mintu
154 #define	ifv_tag		ifv_mib.ifvm_tag
155 
156 struct vlan_multisw {
157 	int	(*vmsw_addmulti)(struct ifvlan *, struct ifreq *);
158 	int	(*vmsw_delmulti)(struct ifvlan *, struct ifreq *);
159 	void	(*vmsw_purgemulti)(struct ifvlan *);
160 };
161 
162 static int	vlan_ether_addmulti(struct ifvlan *, struct ifreq *);
163 static int	vlan_ether_delmulti(struct ifvlan *, struct ifreq *);
164 static void	vlan_ether_purgemulti(struct ifvlan *);
165 
166 const struct vlan_multisw vlan_ether_multisw = {
167 	vlan_ether_addmulti,
168 	vlan_ether_delmulti,
169 	vlan_ether_purgemulti,
170 };
171 
172 static int	vlan_clone_create(struct if_clone *, int);
173 static int	vlan_clone_destroy(struct ifnet *);
174 static int	vlan_config(struct ifvlan *, struct ifnet *);
175 static int	vlan_ioctl(struct ifnet *, u_long, void *);
176 static void	vlan_start(struct ifnet *);
177 static void	vlan_unconfig(struct ifnet *);
178 
179 void		vlanattach(int);
180 
181 /* XXX This should be a hash table with the tag as the basis of the key. */
182 static LIST_HEAD(, ifvlan) ifv_list;
183 
184 static kmutex_t ifv_mtx __cacheline_aligned;
185 
186 struct if_clone vlan_cloner =
187     IF_CLONE_INITIALIZER("vlan", vlan_clone_create, vlan_clone_destroy);
188 
189 /* Used to pad ethernet frames with < ETHER_MIN_LEN bytes */
190 static char vlan_zero_pad_buff[ETHER_MIN_LEN];
191 
192 void
193 vlanattach(int n)
194 {
195 
196 	LIST_INIT(&ifv_list);
197 	mutex_init(&ifv_mtx, MUTEX_DEFAULT, IPL_NONE);
198 	if_clone_attach(&vlan_cloner);
199 }
200 
201 static void
202 vlan_reset_linkname(struct ifnet *ifp)
203 {
204 
205 	/*
206 	 * We start out with a "802.1Q VLAN" type and zero-length
207 	 * addresses.  When we attach to a parent interface, we
208 	 * inherit its type, address length, address, and data link
209 	 * type.
210 	 */
211 
212 	ifp->if_type = IFT_L2VLAN;
213 	ifp->if_addrlen = 0;
214 	ifp->if_dlt = DLT_NULL;
215 	if_alloc_sadl(ifp);
216 }
217 
218 static int
219 vlan_clone_create(struct if_clone *ifc, int unit)
220 {
221 	struct ifvlan *ifv;
222 	struct ifnet *ifp;
223 	int s;
224 
225 	ifv = malloc(sizeof(struct ifvlan), M_DEVBUF, M_WAITOK|M_ZERO);
226 	ifp = &ifv->ifv_if;
227 	LIST_INIT(&ifv->ifv_mc_listhead);
228 
229 	s = splnet();
230 	LIST_INSERT_HEAD(&ifv_list, ifv, ifv_list);
231 	splx(s);
232 
233 	if_initname(ifp, ifc->ifc_name, unit);
234 	ifp->if_softc = ifv;
235 	ifp->if_flags = IFF_BROADCAST | IFF_SIMPLEX | IFF_MULTICAST;
236 	ifp->if_start = vlan_start;
237 	ifp->if_ioctl = vlan_ioctl;
238 	IFQ_SET_READY(&ifp->if_snd);
239 
240 	if_attach(ifp);
241 	vlan_reset_linkname(ifp);
242 
243 	return (0);
244 }
245 
246 static int
247 vlan_clone_destroy(struct ifnet *ifp)
248 {
249 	struct ifvlan *ifv = ifp->if_softc;
250 	int s;
251 
252 	s = splnet();
253 	LIST_REMOVE(ifv, ifv_list);
254 	vlan_unconfig(ifp);
255 	if_detach(ifp);
256 	splx(s);
257 
258 	free(ifv, M_DEVBUF);
259 
260 	return (0);
261 }
262 
263 /*
264  * Configure a VLAN interface.  Must be called at splnet().
265  */
266 static int
267 vlan_config(struct ifvlan *ifv, struct ifnet *p)
268 {
269 	struct ifnet *ifp = &ifv->ifv_if;
270 	int error;
271 
272 	if (ifv->ifv_p != NULL)
273 		return (EBUSY);
274 
275 	switch (p->if_type) {
276 	case IFT_ETHER:
277 	    {
278 		struct ethercom *ec = (void *) p;
279 
280 		ifv->ifv_msw = &vlan_ether_multisw;
281 		ifv->ifv_encaplen = ETHER_VLAN_ENCAP_LEN;
282 		ifv->ifv_mintu = ETHERMIN;
283 
284 		/*
285 		 * If the parent supports the VLAN_MTU capability,
286 		 * i.e. can Tx/Rx larger than ETHER_MAX_LEN frames,
287 		 * enable it.
288 		 */
289 		if (ec->ec_nvlans++ == 0 &&
290 		    (ec->ec_capabilities & ETHERCAP_VLAN_MTU) != 0) {
291 			/*
292 			 * Enable Tx/Rx of VLAN-sized frames.
293 			 */
294 			ec->ec_capenable |= ETHERCAP_VLAN_MTU;
295 			if (p->if_flags & IFF_UP) {
296 				error = if_flags_set(p, p->if_flags);
297 				if (error) {
298 					if (ec->ec_nvlans-- == 1)
299 						ec->ec_capenable &=
300 						    ~ETHERCAP_VLAN_MTU;
301 					return (error);
302 				}
303 			}
304 			ifv->ifv_mtufudge = 0;
305 		} else if ((ec->ec_capabilities & ETHERCAP_VLAN_MTU) == 0) {
306 			/*
307 			 * Fudge the MTU by the encapsulation size.  This
308 			 * makes us incompatible with strictly compliant
309 			 * 802.1Q implementations, but allows us to use
310 			 * the feature with other NetBSD implementations,
311 			 * which might still be useful.
312 			 */
313 			ifv->ifv_mtufudge = ifv->ifv_encaplen;
314 		}
315 
316 		/*
317 		 * If the parent interface can do hardware-assisted
318 		 * VLAN encapsulation, then propagate its hardware-
319 		 * assisted checksumming flags and tcp segmentation
320 		 * offload.
321 		 */
322 		if (ec->ec_capabilities & ETHERCAP_VLAN_HWTAGGING) {
323 		        ec->ec_capenable |= ETHERCAP_VLAN_HWTAGGING;
324 			ifp->if_capabilities = p->if_capabilities &
325 			    (IFCAP_TSOv4 | IFCAP_TSOv6 |
326 			     IFCAP_CSUM_IPv4_Tx|IFCAP_CSUM_IPv4_Rx|
327 			     IFCAP_CSUM_TCPv4_Tx|IFCAP_CSUM_TCPv4_Rx|
328 			     IFCAP_CSUM_UDPv4_Tx|IFCAP_CSUM_UDPv4_Rx|
329 			     IFCAP_CSUM_TCPv6_Tx|IFCAP_CSUM_TCPv6_Rx|
330 			     IFCAP_CSUM_UDPv6_Tx|IFCAP_CSUM_UDPv6_Rx);
331                 }
332 		/*
333 		 * We inherit the parent's Ethernet address.
334 		 */
335 		ether_ifattach(ifp, CLLADDR(p->if_sadl));
336 		ifp->if_hdrlen = sizeof(struct ether_vlan_header); /* XXX? */
337 		break;
338 	    }
339 
340 	default:
341 		return (EPROTONOSUPPORT);
342 	}
343 
344 	ifv->ifv_p = p;
345 	ifv->ifv_if.if_mtu = p->if_mtu - ifv->ifv_mtufudge;
346 	ifv->ifv_if.if_flags = p->if_flags &
347 	    (IFF_UP | IFF_BROADCAST | IFF_SIMPLEX | IFF_MULTICAST);
348 
349 	/*
350 	 * Inherit the if_type from the parent.  This allows us
351 	 * to participate in bridges of that type.
352 	 */
353 	ifv->ifv_if.if_type = p->if_type;
354 
355 	return (0);
356 }
357 
358 /*
359  * Unconfigure a VLAN interface.  Must be called at splnet().
360  */
361 static void
362 vlan_unconfig(struct ifnet *ifp)
363 {
364 	struct ifvlan *ifv = ifp->if_softc;
365 	struct ifnet *p;
366 
367 	mutex_enter(&ifv_mtx);
368 	p = ifv->ifv_p;
369 
370 	if (p == NULL) {
371 		mutex_exit(&ifv_mtx);
372 		return;
373 	}
374 
375 	/*
376  	 * Since the interface is being unconfigured, we need to empty the
377 	 * list of multicast groups that we may have joined while we were
378 	 * alive and remove them from the parent's list also.
379 	 */
380 	(*ifv->ifv_msw->vmsw_purgemulti)(ifv);
381 
382 	/* Disconnect from parent. */
383 	switch (p->if_type) {
384 	case IFT_ETHER:
385 	    {
386 		struct ethercom *ec = (void *) p;
387 
388 		if (ec->ec_nvlans-- == 1) {
389 			/*
390 			 * Disable Tx/Rx of VLAN-sized frames.
391 			 */
392 			ec->ec_capenable &= ~ETHERCAP_VLAN_MTU;
393 			if (p->if_flags & IFF_UP)
394 				(void)if_flags_set(p, p->if_flags);
395 		}
396 
397 		ether_ifdetach(ifp);
398 		/* Restore vlan_ioctl overwritten by ether_ifdetach */
399 		ifp->if_ioctl = vlan_ioctl;
400 		vlan_reset_linkname(ifp);
401 		break;
402 	    }
403 
404 #ifdef DIAGNOSTIC
405 	default:
406 		panic("vlan_unconfig: impossible");
407 #endif
408 	}
409 
410 	ifv->ifv_p = NULL;
411 	ifv->ifv_if.if_mtu = 0;
412 	ifv->ifv_flags = 0;
413 
414 #ifdef INET6
415 	/* To delete v6 link local addresses */
416 	in6_ifdetach(ifp);
417 #endif
418 	if ((ifp->if_flags & IFF_PROMISC) != 0)
419 		ifpromisc(ifp, 0);
420 	if_down(ifp);
421 	ifp->if_flags &= ~(IFF_UP|IFF_RUNNING);
422 	ifp->if_capabilities = 0;
423 
424 	mutex_exit(&ifv_mtx);
425 }
426 
427 /*
428  * Called when a parent interface is detaching; destroy any VLAN
429  * configuration for the parent interface.
430  */
431 void
432 vlan_ifdetach(struct ifnet *p)
433 {
434 	struct ifvlan *ifv;
435 	int s;
436 
437 	s = splnet();
438 
439 	for (ifv = LIST_FIRST(&ifv_list); ifv != NULL;
440 	     ifv = LIST_NEXT(ifv, ifv_list)) {
441 		if (ifv->ifv_p == p)
442 			vlan_unconfig(&ifv->ifv_if);
443 	}
444 
445 	splx(s);
446 }
447 
448 static int
449 vlan_set_promisc(struct ifnet *ifp)
450 {
451 	struct ifvlan *ifv = ifp->if_softc;
452 	int error = 0;
453 
454 	if ((ifp->if_flags & IFF_PROMISC) != 0) {
455 		if ((ifv->ifv_flags & IFVF_PROMISC) == 0) {
456 			error = ifpromisc(ifv->ifv_p, 1);
457 			if (error == 0)
458 				ifv->ifv_flags |= IFVF_PROMISC;
459 		}
460 	} else {
461 		if ((ifv->ifv_flags & IFVF_PROMISC) != 0) {
462 			error = ifpromisc(ifv->ifv_p, 0);
463 			if (error == 0)
464 				ifv->ifv_flags &= ~IFVF_PROMISC;
465 		}
466 	}
467 
468 	return (error);
469 }
470 
471 static int
472 vlan_ioctl(struct ifnet *ifp, u_long cmd, void *data)
473 {
474 	struct lwp *l = curlwp;	/* XXX */
475 	struct ifvlan *ifv = ifp->if_softc;
476 	struct ifaddr *ifa = (struct ifaddr *) data;
477 	struct ifreq *ifr = (struct ifreq *) data;
478 	struct ifnet *pr;
479 	struct ifcapreq *ifcr;
480 	struct vlanreq vlr;
481 	int s, error = 0;
482 
483 	s = splnet();
484 
485 	switch (cmd) {
486 	case SIOCSIFMTU:
487 		if (ifv->ifv_p == NULL)
488 			error = EINVAL;
489 		else if (
490 		    ifr->ifr_mtu > (ifv->ifv_p->if_mtu - ifv->ifv_mtufudge) ||
491 		    ifr->ifr_mtu < (ifv->ifv_mintu - ifv->ifv_mtufudge))
492 			error = EINVAL;
493 		else if ((error = ifioctl_common(ifp, cmd, data)) == ENETRESET)
494 			error = 0;
495 		break;
496 
497 	case SIOCSETVLAN:
498 		if ((error = kauth_authorize_network(l->l_cred,
499 		    KAUTH_NETWORK_INTERFACE,
500 		    KAUTH_REQ_NETWORK_INTERFACE_SETPRIV, ifp, (void *)cmd,
501 		    NULL)) != 0)
502 			break;
503 		if ((error = copyin(ifr->ifr_data, &vlr, sizeof(vlr))) != 0)
504 			break;
505 		if (vlr.vlr_parent[0] == '\0') {
506 			if (ifv->ifv_p != NULL &&
507 			    (ifp->if_flags & IFF_PROMISC) != 0)
508 				error = ifpromisc(ifv->ifv_p, 0);
509 			vlan_unconfig(ifp);
510 			break;
511 		}
512 		if (vlr.vlr_tag != EVL_VLANOFTAG(vlr.vlr_tag)) {
513 			error = EINVAL;		 /* check for valid tag */
514 			break;
515 		}
516 		if ((pr = ifunit(vlr.vlr_parent)) == 0) {
517 			error = ENOENT;
518 			break;
519 		}
520 		if ((error = vlan_config(ifv, pr)) != 0)
521 			break;
522 		ifv->ifv_tag = vlr.vlr_tag;
523 		ifp->if_flags |= IFF_RUNNING;
524 
525 		/* Update promiscuous mode, if necessary. */
526 		vlan_set_promisc(ifp);
527 		break;
528 
529 	case SIOCGETVLAN:
530 		memset(&vlr, 0, sizeof(vlr));
531 		if (ifv->ifv_p != NULL) {
532 			snprintf(vlr.vlr_parent, sizeof(vlr.vlr_parent), "%s",
533 			    ifv->ifv_p->if_xname);
534 			vlr.vlr_tag = ifv->ifv_tag;
535 		}
536 		error = copyout(&vlr, ifr->ifr_data, sizeof(vlr));
537 		break;
538 
539 	case SIOCSIFFLAGS:
540 		if ((error = ifioctl_common(ifp, cmd, data)) != 0)
541 			break;
542 		/*
543 		 * For promiscuous mode, we enable promiscuous mode on
544 		 * the parent if we need promiscuous on the VLAN interface.
545 		 */
546 		if (ifv->ifv_p != NULL)
547 			error = vlan_set_promisc(ifp);
548 		break;
549 
550 	case SIOCADDMULTI:
551 		error = (ifv->ifv_p != NULL) ?
552 		    (*ifv->ifv_msw->vmsw_addmulti)(ifv, ifr) : EINVAL;
553 		break;
554 
555 	case SIOCDELMULTI:
556 		error = (ifv->ifv_p != NULL) ?
557 		    (*ifv->ifv_msw->vmsw_delmulti)(ifv, ifr) : EINVAL;
558 		break;
559 
560 	case SIOCSIFCAP:
561 		ifcr = data;
562 		/* make sure caps are enabled on parent */
563 		if ((ifv->ifv_p->if_capenable & ifcr->ifcr_capenable) !=
564 		    ifcr->ifcr_capenable) {
565 			error = EINVAL;
566 			break;
567 		}
568 		if ((error = ifioctl_common(ifp, cmd, data)) == ENETRESET)
569 			error = 0;
570 		break;
571 	case SIOCINITIFADDR:
572 		if (ifv->ifv_p == NULL) {
573 			error = EINVAL;
574 			break;
575 		}
576 
577 		ifp->if_flags |= IFF_UP;
578 #ifdef INET
579 		if (ifa->ifa_addr->sa_family == AF_INET)
580 			arp_ifinit(ifp, ifa);
581 #endif
582 		break;
583 
584 	default:
585 		error = ether_ioctl(ifp, cmd, data);
586 	}
587 
588 	splx(s);
589 
590 	return (error);
591 }
592 
593 static int
594 vlan_ether_addmulti(struct ifvlan *ifv, struct ifreq *ifr)
595 {
596 	const struct sockaddr *sa = ifreq_getaddr(SIOCADDMULTI, ifr);
597 	struct vlan_mc_entry *mc;
598 	uint8_t addrlo[ETHER_ADDR_LEN], addrhi[ETHER_ADDR_LEN];
599 	int error;
600 
601 	if (sa->sa_len > sizeof(struct sockaddr_storage))
602 		return (EINVAL);
603 
604 	error = ether_addmulti(sa, &ifv->ifv_ec);
605 	if (error != ENETRESET)
606 		return (error);
607 
608 	/*
609 	 * This is new multicast address.  We have to tell parent
610 	 * about it.  Also, remember this multicast address so that
611 	 * we can delete them on unconfigure.
612 	 */
613 	mc = malloc(sizeof(struct vlan_mc_entry), M_DEVBUF, M_NOWAIT);
614 	if (mc == NULL) {
615 		error = ENOMEM;
616 		goto alloc_failed;
617 	}
618 
619 	/*
620 	 * As ether_addmulti() returns ENETRESET, following two
621 	 * statement shouldn't fail.
622 	 */
623 	(void)ether_multiaddr(sa, addrlo, addrhi);
624 	ETHER_LOOKUP_MULTI(addrlo, addrhi, &ifv->ifv_ec, mc->mc_enm);
625 	memcpy(&mc->mc_addr, sa, sa->sa_len);
626 	LIST_INSERT_HEAD(&ifv->ifv_mc_listhead, mc, mc_entries);
627 
628 	error = if_mcast_op(ifv->ifv_p, SIOCADDMULTI, sa);
629 	if (error != 0)
630 		goto ioctl_failed;
631 	return (error);
632 
633  ioctl_failed:
634 	LIST_REMOVE(mc, mc_entries);
635 	free(mc, M_DEVBUF);
636  alloc_failed:
637 	(void)ether_delmulti(sa, &ifv->ifv_ec);
638 	return (error);
639 }
640 
641 static int
642 vlan_ether_delmulti(struct ifvlan *ifv, struct ifreq *ifr)
643 {
644 	const struct sockaddr *sa = ifreq_getaddr(SIOCDELMULTI, ifr);
645 	struct ether_multi *enm;
646 	struct vlan_mc_entry *mc;
647 	uint8_t addrlo[ETHER_ADDR_LEN], addrhi[ETHER_ADDR_LEN];
648 	int error;
649 
650 	/*
651 	 * Find a key to lookup vlan_mc_entry.  We have to do this
652 	 * before calling ether_delmulti for obvious reason.
653 	 */
654 	if ((error = ether_multiaddr(sa, addrlo, addrhi)) != 0)
655 		return (error);
656 	ETHER_LOOKUP_MULTI(addrlo, addrhi, &ifv->ifv_ec, enm);
657 
658 	error = ether_delmulti(sa, &ifv->ifv_ec);
659 	if (error != ENETRESET)
660 		return (error);
661 
662 	/* We no longer use this multicast address.  Tell parent so. */
663 	error = if_mcast_op(ifv->ifv_p, SIOCDELMULTI, sa);
664 	if (error == 0) {
665 		/* And forget about this address. */
666 		for (mc = LIST_FIRST(&ifv->ifv_mc_listhead); mc != NULL;
667 		    mc = LIST_NEXT(mc, mc_entries)) {
668 			if (mc->mc_enm == enm) {
669 				LIST_REMOVE(mc, mc_entries);
670 				free(mc, M_DEVBUF);
671 				break;
672 			}
673 		}
674 		KASSERT(mc != NULL);
675 	} else
676 		(void)ether_addmulti(sa, &ifv->ifv_ec);
677 	return (error);
678 }
679 
680 /*
681  * Delete any multicast address we have asked to add from parent
682  * interface.  Called when the vlan is being unconfigured.
683  */
684 static void
685 vlan_ether_purgemulti(struct ifvlan *ifv)
686 {
687 	struct ifnet *ifp = ifv->ifv_p;		/* Parent. */
688 	struct vlan_mc_entry *mc;
689 
690 	while ((mc = LIST_FIRST(&ifv->ifv_mc_listhead)) != NULL) {
691 		(void)if_mcast_op(ifp, SIOCDELMULTI,
692 		    (const struct sockaddr *)&mc->mc_addr);
693 		LIST_REMOVE(mc, mc_entries);
694 		free(mc, M_DEVBUF);
695 	}
696 }
697 
698 static void
699 vlan_start(struct ifnet *ifp)
700 {
701 	struct ifvlan *ifv = ifp->if_softc;
702 	struct ifnet *p = ifv->ifv_p;
703 	struct ethercom *ec = (void *) ifv->ifv_p;
704 	struct mbuf *m;
705 	int error;
706 	ALTQ_DECL(struct altq_pktattr pktattr;)
707 
708 #ifndef NET_MPSAFE
709 	KASSERT(KERNEL_LOCKED_P());
710 #endif
711 
712 	ifp->if_flags |= IFF_OACTIVE;
713 
714 	for (;;) {
715 		IFQ_DEQUEUE(&ifp->if_snd, m);
716 		if (m == NULL)
717 			break;
718 
719 #ifdef ALTQ
720 		/*
721 		 * If ALTQ is enabled on the parent interface, do
722 		 * classification; the queueing discipline might
723 		 * not require classification, but might require
724 		 * the address family/header pointer in the pktattr.
725 		 */
726 		if (ALTQ_IS_ENABLED(&p->if_snd)) {
727 			switch (p->if_type) {
728 			case IFT_ETHER:
729 				altq_etherclassify(&p->if_snd, m, &pktattr);
730 				break;
731 #ifdef DIAGNOSTIC
732 			default:
733 				panic("vlan_start: impossible (altq)");
734 #endif
735 			}
736 		}
737 #endif /* ALTQ */
738 
739 		bpf_mtap(ifp, m);
740 		/*
741 		 * If the parent can insert the tag itself, just mark
742 		 * the tag in the mbuf header.
743 		 */
744 		if (ec->ec_capabilities & ETHERCAP_VLAN_HWTAGGING) {
745 			struct m_tag *mtag;
746 
747 			mtag = m_tag_get(PACKET_TAG_VLAN, sizeof(u_int),
748 			    M_NOWAIT);
749 			if (mtag == NULL) {
750 				ifp->if_oerrors++;
751 				m_freem(m);
752 				continue;
753 			}
754 			*(u_int *)(mtag + 1) = ifv->ifv_tag;
755 			m_tag_prepend(m, mtag);
756 		} else {
757 			/*
758 			 * insert the tag ourselves
759 			 */
760 			M_PREPEND(m, ifv->ifv_encaplen, M_DONTWAIT);
761 			if (m == NULL) {
762 				printf("%s: unable to prepend encap header",
763 				    ifv->ifv_p->if_xname);
764 				ifp->if_oerrors++;
765 				continue;
766 			}
767 
768 			switch (p->if_type) {
769 			case IFT_ETHER:
770 			    {
771 				struct ether_vlan_header *evl;
772 
773 				if (m->m_len < sizeof(struct ether_vlan_header))
774 					m = m_pullup(m,
775 					    sizeof(struct ether_vlan_header));
776 				if (m == NULL) {
777 					printf("%s: unable to pullup encap "
778 					    "header", ifv->ifv_p->if_xname);
779 					ifp->if_oerrors++;
780 					continue;
781 				}
782 
783 				/*
784 				 * Transform the Ethernet header into an
785 				 * Ethernet header with 802.1Q encapsulation.
786 				 */
787 				memmove(mtod(m, void *),
788 				    mtod(m, char *) + ifv->ifv_encaplen,
789 				    sizeof(struct ether_header));
790 				evl = mtod(m, struct ether_vlan_header *);
791 				evl->evl_proto = evl->evl_encap_proto;
792 				evl->evl_encap_proto = htons(ETHERTYPE_VLAN);
793 				evl->evl_tag = htons(ifv->ifv_tag);
794 
795 				/*
796 				 * To cater for VLAN-aware layer 2 ethernet
797 				 * switches which may need to strip the tag
798 				 * before forwarding the packet, make sure
799 				 * the packet+tag is at least 68 bytes long.
800 				 * This is necessary because our parent will
801 				 * only pad to 64 bytes (ETHER_MIN_LEN) and
802 				 * some switches will not pad by themselves
803 				 * after deleting a tag.
804 				 */
805 				if (m->m_pkthdr.len <
806 				    (ETHER_MIN_LEN + ETHER_VLAN_ENCAP_LEN)) {
807 					m_copyback(m, m->m_pkthdr.len,
808 					    (ETHER_MIN_LEN +
809 					     ETHER_VLAN_ENCAP_LEN) -
810 					     m->m_pkthdr.len,
811 					    vlan_zero_pad_buff);
812 				}
813 				break;
814 			    }
815 
816 #ifdef DIAGNOSTIC
817 			default:
818 				panic("vlan_start: impossible");
819 #endif
820 			}
821 		}
822 
823 		/*
824 		 * Send it, precisely as the parent's output routine
825 		 * would have.  We are already running at splnet.
826 		 */
827 		IFQ_ENQUEUE(&p->if_snd, m, &pktattr, error);
828 		if (error) {
829 			/* mbuf is already freed */
830 			ifp->if_oerrors++;
831 			continue;
832 		}
833 
834 		ifp->if_opackets++;
835 		if ((p->if_flags & (IFF_RUNNING|IFF_OACTIVE)) == IFF_RUNNING)
836 			(*p->if_start)(p);
837 	}
838 
839 	ifp->if_flags &= ~IFF_OACTIVE;
840 }
841 
842 /*
843  * Given an Ethernet frame, find a valid vlan interface corresponding to the
844  * given source interface and tag, then run the real packet through the
845  * parent's input routine.
846  */
847 void
848 vlan_input(struct ifnet *ifp, struct mbuf *m)
849 {
850 	struct ifvlan *ifv;
851 	u_int tag;
852 	struct m_tag *mtag;
853 
854 	mtag = m_tag_find(m, PACKET_TAG_VLAN, NULL);
855 	if (mtag != NULL) {
856 		/* m contains a normal ethernet frame, the tag is in mtag */
857 		tag = EVL_VLANOFTAG(*(u_int *)(mtag + 1));
858 		m_tag_delete(m, mtag);
859 	} else {
860 		switch (ifp->if_type) {
861 		case IFT_ETHER:
862 		    {
863 			struct ether_vlan_header *evl;
864 
865 			if (m->m_len < sizeof(struct ether_vlan_header) &&
866 			    (m = m_pullup(m,
867 			     sizeof(struct ether_vlan_header))) == NULL) {
868 				printf("%s: no memory for VLAN header, "
869 				    "dropping packet.\n", ifp->if_xname);
870 				return;
871 			}
872 			evl = mtod(m, struct ether_vlan_header *);
873 			KASSERT(ntohs(evl->evl_encap_proto) == ETHERTYPE_VLAN);
874 
875 			tag = EVL_VLANOFTAG(ntohs(evl->evl_tag));
876 
877 			/*
878 			 * Restore the original ethertype.  We'll remove
879 			 * the encapsulation after we've found the vlan
880 			 * interface corresponding to the tag.
881 			 */
882 			evl->evl_encap_proto = evl->evl_proto;
883 			break;
884 		    }
885 
886 		default:
887 			tag = (u_int) -1;	/* XXX GCC */
888 #ifdef DIAGNOSTIC
889 			panic("vlan_input: impossible");
890 #endif
891 		}
892 	}
893 
894 	for (ifv = LIST_FIRST(&ifv_list); ifv != NULL;
895 	    ifv = LIST_NEXT(ifv, ifv_list))
896 		if (ifp == ifv->ifv_p && tag == ifv->ifv_tag)
897 			break;
898 
899 	if (ifv == NULL ||
900 	    (ifv->ifv_if.if_flags & (IFF_UP|IFF_RUNNING)) !=
901 	     (IFF_UP|IFF_RUNNING)) {
902 		m_freem(m);
903 		ifp->if_noproto++;
904 		return;
905 	}
906 
907 	/*
908 	 * Now, remove the encapsulation header.  The original
909 	 * header has already been fixed up above.
910 	 */
911 	if (mtag == NULL) {
912 		memmove(mtod(m, char *) + ifv->ifv_encaplen,
913 		    mtod(m, void *), sizeof(struct ether_header));
914 		m_adj(m, ifv->ifv_encaplen);
915 	}
916 
917 	m->m_pkthdr.rcvif = &ifv->ifv_if;
918 	ifv->ifv_if.if_ipackets++;
919 
920 	bpf_mtap(&ifv->ifv_if, m);
921 
922 	m->m_flags &= ~M_PROMISC;
923 	ifv->ifv_if.if_input(&ifv->ifv_if, m);
924 }
925