xref: /netbsd-src/sys/net/if_vlan.c (revision a6f3f22f245acb8ee3bbf6871d7dce989204fa97)
1 /*	$NetBSD: if_vlan.c,v 1.82 2015/08/20 14:40:19 christos 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 1.82 2015/08/20 14:40:19 christos Exp $");
82 
83 #ifdef _KERNEL_OPT
84 #include "opt_inet.h"
85 #include "opt_net_mpsafe.h"
86 #endif
87 
88 #include <sys/param.h>
89 #include <sys/kernel.h>
90 #include <sys/mbuf.h>
91 #include <sys/queue.h>
92 #include <sys/socket.h>
93 #include <sys/sockio.h>
94 #include <sys/systm.h>
95 #include <sys/proc.h>
96 #include <sys/kauth.h>
97 #include <sys/mutex.h>
98 
99 #include <net/bpf.h>
100 #include <net/if.h>
101 #include <net/if_dl.h>
102 #include <net/if_types.h>
103 #include <net/if_ether.h>
104 #include <net/if_vlanvar.h>
105 
106 #ifdef INET
107 #include <netinet/in.h>
108 #include <netinet/if_inarp.h>
109 #endif
110 #ifdef INET6
111 #include <netinet6/in6_ifattach.h>
112 #endif
113 
114 #include "ioconf.h"
115 
116 struct vlan_mc_entry {
117 	LIST_ENTRY(vlan_mc_entry)	mc_entries;
118 	/*
119 	 * A key to identify this entry.  The mc_addr below can't be
120 	 * used since multiple sockaddr may mapped into the same
121 	 * ether_multi (e.g., AF_UNSPEC).
122 	 */
123 	union {
124 		struct ether_multi	*mcu_enm;
125 	} mc_u;
126 	struct sockaddr_storage		mc_addr;
127 };
128 
129 #define	mc_enm		mc_u.mcu_enm
130 
131 struct ifvlan {
132 	union {
133 		struct ethercom ifvu_ec;
134 	} ifv_u;
135 	struct ifnet *ifv_p;	/* parent interface of this vlan */
136 	struct ifv_linkmib {
137 		const struct vlan_multisw *ifvm_msw;
138 		int	ifvm_encaplen;	/* encapsulation length */
139 		int	ifvm_mtufudge;	/* MTU fudged by this much */
140 		int	ifvm_mintu;	/* min transmission unit */
141 		uint16_t ifvm_proto;	/* encapsulation ethertype */
142 		uint16_t ifvm_tag;	/* tag to apply on packets */
143 	} ifv_mib;
144 	LIST_HEAD(__vlan_mchead, vlan_mc_entry) ifv_mc_listhead;
145 	LIST_ENTRY(ifvlan) ifv_list;
146 	int ifv_flags;
147 };
148 
149 #define	IFVF_PROMISC	0x01		/* promiscuous mode enabled */
150 
151 #define	ifv_ec		ifv_u.ifvu_ec
152 
153 #define	ifv_if		ifv_ec.ec_if
154 
155 #define	ifv_msw		ifv_mib.ifvm_msw
156 #define	ifv_encaplen	ifv_mib.ifvm_encaplen
157 #define	ifv_mtufudge	ifv_mib.ifvm_mtufudge
158 #define	ifv_mintu	ifv_mib.ifvm_mintu
159 #define	ifv_tag		ifv_mib.ifvm_tag
160 
161 struct vlan_multisw {
162 	int	(*vmsw_addmulti)(struct ifvlan *, struct ifreq *);
163 	int	(*vmsw_delmulti)(struct ifvlan *, struct ifreq *);
164 	void	(*vmsw_purgemulti)(struct ifvlan *);
165 };
166 
167 static int	vlan_ether_addmulti(struct ifvlan *, struct ifreq *);
168 static int	vlan_ether_delmulti(struct ifvlan *, struct ifreq *);
169 static void	vlan_ether_purgemulti(struct ifvlan *);
170 
171 const struct vlan_multisw vlan_ether_multisw = {
172 	vlan_ether_addmulti,
173 	vlan_ether_delmulti,
174 	vlan_ether_purgemulti,
175 };
176 
177 static int	vlan_clone_create(struct if_clone *, int);
178 static int	vlan_clone_destroy(struct ifnet *);
179 static int	vlan_config(struct ifvlan *, struct ifnet *);
180 static int	vlan_ioctl(struct ifnet *, u_long, void *);
181 static void	vlan_start(struct ifnet *);
182 static void	vlan_unconfig(struct ifnet *);
183 
184 /* XXX This should be a hash table with the tag as the basis of the key. */
185 static LIST_HEAD(, ifvlan) ifv_list;
186 
187 static kmutex_t ifv_mtx __cacheline_aligned;
188 
189 struct if_clone vlan_cloner =
190     IF_CLONE_INITIALIZER("vlan", vlan_clone_create, vlan_clone_destroy);
191 
192 /* Used to pad ethernet frames with < ETHER_MIN_LEN bytes */
193 static char vlan_zero_pad_buff[ETHER_MIN_LEN];
194 
195 void
196 vlanattach(int n)
197 {
198 
199 	LIST_INIT(&ifv_list);
200 	mutex_init(&ifv_mtx, MUTEX_DEFAULT, IPL_NONE);
201 	if_clone_attach(&vlan_cloner);
202 }
203 
204 static void
205 vlan_reset_linkname(struct ifnet *ifp)
206 {
207 
208 	/*
209 	 * We start out with a "802.1Q VLAN" type and zero-length
210 	 * addresses.  When we attach to a parent interface, we
211 	 * inherit its type, address length, address, and data link
212 	 * type.
213 	 */
214 
215 	ifp->if_type = IFT_L2VLAN;
216 	ifp->if_addrlen = 0;
217 	ifp->if_dlt = DLT_NULL;
218 	if_alloc_sadl(ifp);
219 }
220 
221 static int
222 vlan_clone_create(struct if_clone *ifc, int unit)
223 {
224 	struct ifvlan *ifv;
225 	struct ifnet *ifp;
226 	int s;
227 
228 	ifv = malloc(sizeof(struct ifvlan), M_DEVBUF, M_WAITOK|M_ZERO);
229 	ifp = &ifv->ifv_if;
230 	LIST_INIT(&ifv->ifv_mc_listhead);
231 
232 	s = splnet();
233 	LIST_INSERT_HEAD(&ifv_list, ifv, ifv_list);
234 	splx(s);
235 
236 	if_initname(ifp, ifc->ifc_name, unit);
237 	ifp->if_softc = ifv;
238 	ifp->if_flags = IFF_BROADCAST | IFF_SIMPLEX | IFF_MULTICAST;
239 	ifp->if_start = vlan_start;
240 	ifp->if_ioctl = vlan_ioctl;
241 	IFQ_SET_READY(&ifp->if_snd);
242 
243 	if_attach(ifp);
244 	vlan_reset_linkname(ifp);
245 
246 	return (0);
247 }
248 
249 static int
250 vlan_clone_destroy(struct ifnet *ifp)
251 {
252 	struct ifvlan *ifv = ifp->if_softc;
253 	int s;
254 
255 	s = splnet();
256 	LIST_REMOVE(ifv, ifv_list);
257 	vlan_unconfig(ifp);
258 	if_detach(ifp);
259 	splx(s);
260 
261 	free(ifv, M_DEVBUF);
262 
263 	return (0);
264 }
265 
266 /*
267  * Configure a VLAN interface.  Must be called at splnet().
268  */
269 static int
270 vlan_config(struct ifvlan *ifv, struct ifnet *p)
271 {
272 	struct ifnet *ifp = &ifv->ifv_if;
273 	int error;
274 
275 	if (ifv->ifv_p != NULL)
276 		return (EBUSY);
277 
278 	switch (p->if_type) {
279 	case IFT_ETHER:
280 	    {
281 		struct ethercom *ec = (void *) p;
282 
283 		ifv->ifv_msw = &vlan_ether_multisw;
284 		ifv->ifv_encaplen = ETHER_VLAN_ENCAP_LEN;
285 		ifv->ifv_mintu = ETHERMIN;
286 
287 		/*
288 		 * If the parent supports the VLAN_MTU capability,
289 		 * i.e. can Tx/Rx larger than ETHER_MAX_LEN frames,
290 		 * enable it.
291 		 */
292 		if (ec->ec_nvlans++ == 0 &&
293 		    (ec->ec_capabilities & ETHERCAP_VLAN_MTU) != 0) {
294 			/*
295 			 * Enable Tx/Rx of VLAN-sized frames.
296 			 */
297 			ec->ec_capenable |= ETHERCAP_VLAN_MTU;
298 			if (p->if_flags & IFF_UP) {
299 				error = if_flags_set(p, p->if_flags);
300 				if (error) {
301 					if (ec->ec_nvlans-- == 1)
302 						ec->ec_capenable &=
303 						    ~ETHERCAP_VLAN_MTU;
304 					return (error);
305 				}
306 			}
307 			ifv->ifv_mtufudge = 0;
308 		} else if ((ec->ec_capabilities & ETHERCAP_VLAN_MTU) == 0) {
309 			/*
310 			 * Fudge the MTU by the encapsulation size.  This
311 			 * makes us incompatible with strictly compliant
312 			 * 802.1Q implementations, but allows us to use
313 			 * the feature with other NetBSD implementations,
314 			 * which might still be useful.
315 			 */
316 			ifv->ifv_mtufudge = ifv->ifv_encaplen;
317 		}
318 
319 		/*
320 		 * If the parent interface can do hardware-assisted
321 		 * VLAN encapsulation, then propagate its hardware-
322 		 * assisted checksumming flags and tcp segmentation
323 		 * offload.
324 		 */
325 		if (ec->ec_capabilities & ETHERCAP_VLAN_HWTAGGING) {
326 		        ec->ec_capenable |= ETHERCAP_VLAN_HWTAGGING;
327 			ifp->if_capabilities = p->if_capabilities &
328 			    (IFCAP_TSOv4 | IFCAP_TSOv6 |
329 			     IFCAP_CSUM_IPv4_Tx|IFCAP_CSUM_IPv4_Rx|
330 			     IFCAP_CSUM_TCPv4_Tx|IFCAP_CSUM_TCPv4_Rx|
331 			     IFCAP_CSUM_UDPv4_Tx|IFCAP_CSUM_UDPv4_Rx|
332 			     IFCAP_CSUM_TCPv6_Tx|IFCAP_CSUM_TCPv6_Rx|
333 			     IFCAP_CSUM_UDPv6_Tx|IFCAP_CSUM_UDPv6_Rx);
334                 }
335 		/*
336 		 * We inherit the parent's Ethernet address.
337 		 */
338 		ether_ifattach(ifp, CLLADDR(p->if_sadl));
339 		ifp->if_hdrlen = sizeof(struct ether_vlan_header); /* XXX? */
340 		break;
341 	    }
342 
343 	default:
344 		return (EPROTONOSUPPORT);
345 	}
346 
347 	ifv->ifv_p = p;
348 	ifv->ifv_if.if_mtu = p->if_mtu - ifv->ifv_mtufudge;
349 	ifv->ifv_if.if_flags = p->if_flags &
350 	    (IFF_UP | IFF_BROADCAST | IFF_SIMPLEX | IFF_MULTICAST);
351 
352 	/*
353 	 * Inherit the if_type from the parent.  This allows us
354 	 * to participate in bridges of that type.
355 	 */
356 	ifv->ifv_if.if_type = p->if_type;
357 
358 	return (0);
359 }
360 
361 /*
362  * Unconfigure a VLAN interface.  Must be called at splnet().
363  */
364 static void
365 vlan_unconfig(struct ifnet *ifp)
366 {
367 	struct ifvlan *ifv = ifp->if_softc;
368 	struct ifnet *p;
369 
370 	mutex_enter(&ifv_mtx);
371 	p = ifv->ifv_p;
372 
373 	if (p == NULL) {
374 		mutex_exit(&ifv_mtx);
375 		return;
376 	}
377 
378 	/*
379  	 * Since the interface is being unconfigured, we need to empty the
380 	 * list of multicast groups that we may have joined while we were
381 	 * alive and remove them from the parent's list also.
382 	 */
383 	(*ifv->ifv_msw->vmsw_purgemulti)(ifv);
384 
385 	/* Disconnect from parent. */
386 	switch (p->if_type) {
387 	case IFT_ETHER:
388 	    {
389 		struct ethercom *ec = (void *) p;
390 
391 		if (ec->ec_nvlans-- == 1) {
392 			/*
393 			 * Disable Tx/Rx of VLAN-sized frames.
394 			 */
395 			ec->ec_capenable &= ~ETHERCAP_VLAN_MTU;
396 			if (p->if_flags & IFF_UP)
397 				(void)if_flags_set(p, p->if_flags);
398 		}
399 
400 		ether_ifdetach(ifp);
401 		/* Restore vlan_ioctl overwritten by ether_ifdetach */
402 		ifp->if_ioctl = vlan_ioctl;
403 		vlan_reset_linkname(ifp);
404 		break;
405 	    }
406 
407 #ifdef DIAGNOSTIC
408 	default:
409 		panic("vlan_unconfig: impossible");
410 #endif
411 	}
412 
413 	ifv->ifv_p = NULL;
414 	ifv->ifv_if.if_mtu = 0;
415 	ifv->ifv_flags = 0;
416 
417 #ifdef INET6
418 	/* To delete v6 link local addresses */
419 	in6_ifdetach(ifp);
420 #endif
421 	if ((ifp->if_flags & IFF_PROMISC) != 0)
422 		ifpromisc(ifp, 0);
423 	if_down(ifp);
424 	ifp->if_flags &= ~(IFF_UP|IFF_RUNNING);
425 	ifp->if_capabilities = 0;
426 
427 	mutex_exit(&ifv_mtx);
428 }
429 
430 /*
431  * Called when a parent interface is detaching; destroy any VLAN
432  * configuration for the parent interface.
433  */
434 void
435 vlan_ifdetach(struct ifnet *p)
436 {
437 	struct ifvlan *ifv;
438 	int s;
439 
440 	s = splnet();
441 
442 	for (ifv = LIST_FIRST(&ifv_list); ifv != NULL;
443 	     ifv = LIST_NEXT(ifv, ifv_list)) {
444 		if (ifv->ifv_p == p)
445 			vlan_unconfig(&ifv->ifv_if);
446 	}
447 
448 	splx(s);
449 }
450 
451 static int
452 vlan_set_promisc(struct ifnet *ifp)
453 {
454 	struct ifvlan *ifv = ifp->if_softc;
455 	int error = 0;
456 
457 	if ((ifp->if_flags & IFF_PROMISC) != 0) {
458 		if ((ifv->ifv_flags & IFVF_PROMISC) == 0) {
459 			error = ifpromisc(ifv->ifv_p, 1);
460 			if (error == 0)
461 				ifv->ifv_flags |= IFVF_PROMISC;
462 		}
463 	} else {
464 		if ((ifv->ifv_flags & IFVF_PROMISC) != 0) {
465 			error = ifpromisc(ifv->ifv_p, 0);
466 			if (error == 0)
467 				ifv->ifv_flags &= ~IFVF_PROMISC;
468 		}
469 	}
470 
471 	return (error);
472 }
473 
474 static int
475 vlan_ioctl(struct ifnet *ifp, u_long cmd, void *data)
476 {
477 	struct lwp *l = curlwp;	/* XXX */
478 	struct ifvlan *ifv = ifp->if_softc;
479 	struct ifaddr *ifa = (struct ifaddr *) data;
480 	struct ifreq *ifr = (struct ifreq *) data;
481 	struct ifnet *pr;
482 	struct ifcapreq *ifcr;
483 	struct vlanreq vlr;
484 	int s, error = 0;
485 
486 	s = splnet();
487 
488 	switch (cmd) {
489 	case SIOCSIFMTU:
490 		if (ifv->ifv_p == NULL)
491 			error = EINVAL;
492 		else if (
493 		    ifr->ifr_mtu > (ifv->ifv_p->if_mtu - ifv->ifv_mtufudge) ||
494 		    ifr->ifr_mtu < (ifv->ifv_mintu - ifv->ifv_mtufudge))
495 			error = EINVAL;
496 		else if ((error = ifioctl_common(ifp, cmd, data)) == ENETRESET)
497 			error = 0;
498 		break;
499 
500 	case SIOCSETVLAN:
501 		if ((error = kauth_authorize_network(l->l_cred,
502 		    KAUTH_NETWORK_INTERFACE,
503 		    KAUTH_REQ_NETWORK_INTERFACE_SETPRIV, ifp, (void *)cmd,
504 		    NULL)) != 0)
505 			break;
506 		if ((error = copyin(ifr->ifr_data, &vlr, sizeof(vlr))) != 0)
507 			break;
508 		if (vlr.vlr_parent[0] == '\0') {
509 			if (ifv->ifv_p != NULL &&
510 			    (ifp->if_flags & IFF_PROMISC) != 0)
511 				error = ifpromisc(ifv->ifv_p, 0);
512 			vlan_unconfig(ifp);
513 			break;
514 		}
515 		if (vlr.vlr_tag != EVL_VLANOFTAG(vlr.vlr_tag)) {
516 			error = EINVAL;		 /* check for valid tag */
517 			break;
518 		}
519 		if ((pr = ifunit(vlr.vlr_parent)) == 0) {
520 			error = ENOENT;
521 			break;
522 		}
523 		if ((error = vlan_config(ifv, pr)) != 0)
524 			break;
525 		ifv->ifv_tag = vlr.vlr_tag;
526 		ifp->if_flags |= IFF_RUNNING;
527 
528 		/* Update promiscuous mode, if necessary. */
529 		vlan_set_promisc(ifp);
530 		break;
531 
532 	case SIOCGETVLAN:
533 		memset(&vlr, 0, sizeof(vlr));
534 		if (ifv->ifv_p != NULL) {
535 			snprintf(vlr.vlr_parent, sizeof(vlr.vlr_parent), "%s",
536 			    ifv->ifv_p->if_xname);
537 			vlr.vlr_tag = ifv->ifv_tag;
538 		}
539 		error = copyout(&vlr, ifr->ifr_data, sizeof(vlr));
540 		break;
541 
542 	case SIOCSIFFLAGS:
543 		if ((error = ifioctl_common(ifp, cmd, data)) != 0)
544 			break;
545 		/*
546 		 * For promiscuous mode, we enable promiscuous mode on
547 		 * the parent if we need promiscuous on the VLAN interface.
548 		 */
549 		if (ifv->ifv_p != NULL)
550 			error = vlan_set_promisc(ifp);
551 		break;
552 
553 	case SIOCADDMULTI:
554 		error = (ifv->ifv_p != NULL) ?
555 		    (*ifv->ifv_msw->vmsw_addmulti)(ifv, ifr) : EINVAL;
556 		break;
557 
558 	case SIOCDELMULTI:
559 		error = (ifv->ifv_p != NULL) ?
560 		    (*ifv->ifv_msw->vmsw_delmulti)(ifv, ifr) : EINVAL;
561 		break;
562 
563 	case SIOCSIFCAP:
564 		ifcr = data;
565 		/* make sure caps are enabled on parent */
566 		if ((ifv->ifv_p->if_capenable & ifcr->ifcr_capenable) !=
567 		    ifcr->ifcr_capenable) {
568 			error = EINVAL;
569 			break;
570 		}
571 		if ((error = ifioctl_common(ifp, cmd, data)) == ENETRESET)
572 			error = 0;
573 		break;
574 	case SIOCINITIFADDR:
575 		if (ifv->ifv_p == NULL) {
576 			error = EINVAL;
577 			break;
578 		}
579 
580 		ifp->if_flags |= IFF_UP;
581 #ifdef INET
582 		if (ifa->ifa_addr->sa_family == AF_INET)
583 			arp_ifinit(ifp, ifa);
584 #endif
585 		break;
586 
587 	default:
588 		error = ether_ioctl(ifp, cmd, data);
589 	}
590 
591 	splx(s);
592 
593 	return (error);
594 }
595 
596 static int
597 vlan_ether_addmulti(struct ifvlan *ifv, struct ifreq *ifr)
598 {
599 	const struct sockaddr *sa = ifreq_getaddr(SIOCADDMULTI, ifr);
600 	struct vlan_mc_entry *mc;
601 	uint8_t addrlo[ETHER_ADDR_LEN], addrhi[ETHER_ADDR_LEN];
602 	int error;
603 
604 	if (sa->sa_len > sizeof(struct sockaddr_storage))
605 		return (EINVAL);
606 
607 	error = ether_addmulti(sa, &ifv->ifv_ec);
608 	if (error != ENETRESET)
609 		return (error);
610 
611 	/*
612 	 * This is new multicast address.  We have to tell parent
613 	 * about it.  Also, remember this multicast address so that
614 	 * we can delete them on unconfigure.
615 	 */
616 	mc = malloc(sizeof(struct vlan_mc_entry), M_DEVBUF, M_NOWAIT);
617 	if (mc == NULL) {
618 		error = ENOMEM;
619 		goto alloc_failed;
620 	}
621 
622 	/*
623 	 * As ether_addmulti() returns ENETRESET, following two
624 	 * statement shouldn't fail.
625 	 */
626 	(void)ether_multiaddr(sa, addrlo, addrhi);
627 	ETHER_LOOKUP_MULTI(addrlo, addrhi, &ifv->ifv_ec, mc->mc_enm);
628 	memcpy(&mc->mc_addr, sa, sa->sa_len);
629 	LIST_INSERT_HEAD(&ifv->ifv_mc_listhead, mc, mc_entries);
630 
631 	error = if_mcast_op(ifv->ifv_p, SIOCADDMULTI, sa);
632 	if (error != 0)
633 		goto ioctl_failed;
634 	return (error);
635 
636  ioctl_failed:
637 	LIST_REMOVE(mc, mc_entries);
638 	free(mc, M_DEVBUF);
639  alloc_failed:
640 	(void)ether_delmulti(sa, &ifv->ifv_ec);
641 	return (error);
642 }
643 
644 static int
645 vlan_ether_delmulti(struct ifvlan *ifv, struct ifreq *ifr)
646 {
647 	const struct sockaddr *sa = ifreq_getaddr(SIOCDELMULTI, ifr);
648 	struct ether_multi *enm;
649 	struct vlan_mc_entry *mc;
650 	uint8_t addrlo[ETHER_ADDR_LEN], addrhi[ETHER_ADDR_LEN];
651 	int error;
652 
653 	/*
654 	 * Find a key to lookup vlan_mc_entry.  We have to do this
655 	 * before calling ether_delmulti for obvious reason.
656 	 */
657 	if ((error = ether_multiaddr(sa, addrlo, addrhi)) != 0)
658 		return (error);
659 	ETHER_LOOKUP_MULTI(addrlo, addrhi, &ifv->ifv_ec, enm);
660 
661 	error = ether_delmulti(sa, &ifv->ifv_ec);
662 	if (error != ENETRESET)
663 		return (error);
664 
665 	/* We no longer use this multicast address.  Tell parent so. */
666 	error = if_mcast_op(ifv->ifv_p, SIOCDELMULTI, sa);
667 	if (error == 0) {
668 		/* And forget about this address. */
669 		for (mc = LIST_FIRST(&ifv->ifv_mc_listhead); mc != NULL;
670 		    mc = LIST_NEXT(mc, mc_entries)) {
671 			if (mc->mc_enm == enm) {
672 				LIST_REMOVE(mc, mc_entries);
673 				free(mc, M_DEVBUF);
674 				break;
675 			}
676 		}
677 		KASSERT(mc != NULL);
678 	} else
679 		(void)ether_addmulti(sa, &ifv->ifv_ec);
680 	return (error);
681 }
682 
683 /*
684  * Delete any multicast address we have asked to add from parent
685  * interface.  Called when the vlan is being unconfigured.
686  */
687 static void
688 vlan_ether_purgemulti(struct ifvlan *ifv)
689 {
690 	struct ifnet *ifp = ifv->ifv_p;		/* Parent. */
691 	struct vlan_mc_entry *mc;
692 
693 	while ((mc = LIST_FIRST(&ifv->ifv_mc_listhead)) != NULL) {
694 		(void)if_mcast_op(ifp, SIOCDELMULTI,
695 		    (const struct sockaddr *)&mc->mc_addr);
696 		LIST_REMOVE(mc, mc_entries);
697 		free(mc, M_DEVBUF);
698 	}
699 }
700 
701 static void
702 vlan_start(struct ifnet *ifp)
703 {
704 	struct ifvlan *ifv = ifp->if_softc;
705 	struct ifnet *p = ifv->ifv_p;
706 	struct ethercom *ec = (void *) ifv->ifv_p;
707 	struct mbuf *m;
708 	int error;
709 	ALTQ_DECL(struct altq_pktattr pktattr;)
710 
711 #ifndef NET_MPSAFE
712 	KASSERT(KERNEL_LOCKED_P());
713 #endif
714 
715 	ifp->if_flags |= IFF_OACTIVE;
716 
717 	for (;;) {
718 		IFQ_DEQUEUE(&ifp->if_snd, m);
719 		if (m == NULL)
720 			break;
721 
722 #ifdef ALTQ
723 		/*
724 		 * If ALTQ is enabled on the parent interface, do
725 		 * classification; the queueing discipline might
726 		 * not require classification, but might require
727 		 * the address family/header pointer in the pktattr.
728 		 */
729 		if (ALTQ_IS_ENABLED(&p->if_snd)) {
730 			switch (p->if_type) {
731 			case IFT_ETHER:
732 				altq_etherclassify(&p->if_snd, m, &pktattr);
733 				break;
734 #ifdef DIAGNOSTIC
735 			default:
736 				panic("vlan_start: impossible (altq)");
737 #endif
738 			}
739 		}
740 #endif /* ALTQ */
741 
742 		bpf_mtap(ifp, m);
743 		/*
744 		 * If the parent can insert the tag itself, just mark
745 		 * the tag in the mbuf header.
746 		 */
747 		if (ec->ec_capabilities & ETHERCAP_VLAN_HWTAGGING) {
748 			struct m_tag *mtag;
749 
750 			mtag = m_tag_get(PACKET_TAG_VLAN, sizeof(u_int),
751 			    M_NOWAIT);
752 			if (mtag == NULL) {
753 				ifp->if_oerrors++;
754 				m_freem(m);
755 				continue;
756 			}
757 			*(u_int *)(mtag + 1) = ifv->ifv_tag;
758 			m_tag_prepend(m, mtag);
759 		} else {
760 			/*
761 			 * insert the tag ourselves
762 			 */
763 			M_PREPEND(m, ifv->ifv_encaplen, M_DONTWAIT);
764 			if (m == NULL) {
765 				printf("%s: unable to prepend encap header",
766 				    ifv->ifv_p->if_xname);
767 				ifp->if_oerrors++;
768 				continue;
769 			}
770 
771 			switch (p->if_type) {
772 			case IFT_ETHER:
773 			    {
774 				struct ether_vlan_header *evl;
775 
776 				if (m->m_len < sizeof(struct ether_vlan_header))
777 					m = m_pullup(m,
778 					    sizeof(struct ether_vlan_header));
779 				if (m == NULL) {
780 					printf("%s: unable to pullup encap "
781 					    "header", ifv->ifv_p->if_xname);
782 					ifp->if_oerrors++;
783 					continue;
784 				}
785 
786 				/*
787 				 * Transform the Ethernet header into an
788 				 * Ethernet header with 802.1Q encapsulation.
789 				 */
790 				memmove(mtod(m, void *),
791 				    mtod(m, char *) + ifv->ifv_encaplen,
792 				    sizeof(struct ether_header));
793 				evl = mtod(m, struct ether_vlan_header *);
794 				evl->evl_proto = evl->evl_encap_proto;
795 				evl->evl_encap_proto = htons(ETHERTYPE_VLAN);
796 				evl->evl_tag = htons(ifv->ifv_tag);
797 
798 				/*
799 				 * To cater for VLAN-aware layer 2 ethernet
800 				 * switches which may need to strip the tag
801 				 * before forwarding the packet, make sure
802 				 * the packet+tag is at least 68 bytes long.
803 				 * This is necessary because our parent will
804 				 * only pad to 64 bytes (ETHER_MIN_LEN) and
805 				 * some switches will not pad by themselves
806 				 * after deleting a tag.
807 				 */
808 				if (m->m_pkthdr.len <
809 				    (ETHER_MIN_LEN - ETHER_CRC_LEN +
810 				     ETHER_VLAN_ENCAP_LEN)) {
811 					m_copyback(m, m->m_pkthdr.len,
812 					    (ETHER_MIN_LEN - ETHER_CRC_LEN +
813 					     ETHER_VLAN_ENCAP_LEN) -
814 					     m->m_pkthdr.len,
815 					    vlan_zero_pad_buff);
816 				}
817 				break;
818 			    }
819 
820 #ifdef DIAGNOSTIC
821 			default:
822 				panic("vlan_start: impossible");
823 #endif
824 			}
825 		}
826 
827 		/*
828 		 * Send it, precisely as the parent's output routine
829 		 * would have.  We are already running at splnet.
830 		 */
831 		IFQ_ENQUEUE(&p->if_snd, m, &pktattr, error);
832 		if (error) {
833 			/* mbuf is already freed */
834 			ifp->if_oerrors++;
835 			continue;
836 		}
837 
838 		ifp->if_opackets++;
839 
840 		p->if_obytes += m->m_pkthdr.len;
841 		if (m->m_flags & M_MCAST)
842 			p->if_omcasts++;
843 		if ((p->if_flags & (IFF_RUNNING|IFF_OACTIVE)) == IFF_RUNNING)
844 			(*p->if_start)(p);
845 	}
846 
847 	ifp->if_flags &= ~IFF_OACTIVE;
848 }
849 
850 /*
851  * Given an Ethernet frame, find a valid vlan interface corresponding to the
852  * given source interface and tag, then run the real packet through the
853  * parent's input routine.
854  */
855 void
856 vlan_input(struct ifnet *ifp, struct mbuf *m)
857 {
858 	struct ifvlan *ifv;
859 	u_int tag;
860 	struct m_tag *mtag;
861 
862 	mtag = m_tag_find(m, PACKET_TAG_VLAN, NULL);
863 	if (mtag != NULL) {
864 		/* m contains a normal ethernet frame, the tag is in mtag */
865 		tag = EVL_VLANOFTAG(*(u_int *)(mtag + 1));
866 		m_tag_delete(m, mtag);
867 	} else {
868 		switch (ifp->if_type) {
869 		case IFT_ETHER:
870 		    {
871 			struct ether_vlan_header *evl;
872 
873 			if (m->m_len < sizeof(struct ether_vlan_header) &&
874 			    (m = m_pullup(m,
875 			     sizeof(struct ether_vlan_header))) == NULL) {
876 				printf("%s: no memory for VLAN header, "
877 				    "dropping packet.\n", ifp->if_xname);
878 				return;
879 			}
880 			evl = mtod(m, struct ether_vlan_header *);
881 			KASSERT(ntohs(evl->evl_encap_proto) == ETHERTYPE_VLAN);
882 
883 			tag = EVL_VLANOFTAG(ntohs(evl->evl_tag));
884 
885 			/*
886 			 * Restore the original ethertype.  We'll remove
887 			 * the encapsulation after we've found the vlan
888 			 * interface corresponding to the tag.
889 			 */
890 			evl->evl_encap_proto = evl->evl_proto;
891 			break;
892 		    }
893 
894 		default:
895 			tag = (u_int) -1;	/* XXX GCC */
896 #ifdef DIAGNOSTIC
897 			panic("vlan_input: impossible");
898 #endif
899 		}
900 	}
901 
902 	for (ifv = LIST_FIRST(&ifv_list); ifv != NULL;
903 	    ifv = LIST_NEXT(ifv, ifv_list))
904 		if (ifp == ifv->ifv_p && tag == ifv->ifv_tag)
905 			break;
906 
907 	if (ifv == NULL ||
908 	    (ifv->ifv_if.if_flags & (IFF_UP|IFF_RUNNING)) !=
909 	     (IFF_UP|IFF_RUNNING)) {
910 		m_freem(m);
911 		ifp->if_noproto++;
912 		return;
913 	}
914 
915 	/*
916 	 * Now, remove the encapsulation header.  The original
917 	 * header has already been fixed up above.
918 	 */
919 	if (mtag == NULL) {
920 		memmove(mtod(m, char *) + ifv->ifv_encaplen,
921 		    mtod(m, void *), sizeof(struct ether_header));
922 		m_adj(m, ifv->ifv_encaplen);
923 	}
924 
925 	m->m_pkthdr.rcvif = &ifv->ifv_if;
926 	ifv->ifv_if.if_ipackets++;
927 
928 	bpf_mtap(&ifv->ifv_if, m);
929 
930 	m->m_flags &= ~M_PROMISC;
931 	ifv->ifv_if.if_input(&ifv->ifv_if, m);
932 }
933