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if_vlan.c revision 1.62.2.1
      1 /*	$NetBSD: if_vlan.c,v 1.62.2.1 2009/05/13 17:22:20 jym 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 1.62.2.1 2009/05/13 17:22:20 jym Exp $");
     82 
     83 #include "opt_inet.h"
     84 #include "bpfilter.h"
     85 
     86 #include <sys/param.h>
     87 #include <sys/kernel.h>
     88 #include <sys/mbuf.h>
     89 #include <sys/queue.h>
     90 #include <sys/socket.h>
     91 #include <sys/sockio.h>
     92 #include <sys/systm.h>
     93 #include <sys/proc.h>
     94 #include <sys/kauth.h>
     95 
     96 #if NBPFILTER > 0
     97 #include <net/bpf.h>
     98 #endif
     99 #include <net/if.h>
    100 #include <net/if_dl.h>
    101 #include <net/if_types.h>
    102 #include <net/if_ether.h>
    103 #include <net/if_vlanvar.h>
    104 
    105 #ifdef INET
    106 #include <netinet/in.h>
    107 #include <netinet/if_inarp.h>
    108 #endif
    109 
    110 struct vlan_mc_entry {
    111 	LIST_ENTRY(vlan_mc_entry)	mc_entries;
    112 	/*
    113 	 * A key to identify this entry.  The mc_addr below can't be
    114 	 * used since multiple sockaddr may mapped into the same
    115 	 * ether_multi (e.g., AF_UNSPEC).
    116 	 */
    117 	union {
    118 		struct ether_multi	*mcu_enm;
    119 	} mc_u;
    120 	struct sockaddr_storage		mc_addr;
    121 };
    122 
    123 #define	mc_enm		mc_u.mcu_enm
    124 
    125 struct ifvlan {
    126 	union {
    127 		struct ethercom ifvu_ec;
    128 	} ifv_u;
    129 	struct ifnet *ifv_p;	/* parent interface of this vlan */
    130 	struct ifv_linkmib {
    131 		const struct vlan_multisw *ifvm_msw;
    132 		int	ifvm_encaplen;	/* encapsulation length */
    133 		int	ifvm_mtufudge;	/* MTU fudged by this much */
    134 		int	ifvm_mintu;	/* min transmission unit */
    135 		uint16_t ifvm_proto;	/* encapsulation ethertype */
    136 		uint16_t ifvm_tag;	/* tag to apply on packets */
    137 	} ifv_mib;
    138 	LIST_HEAD(__vlan_mchead, vlan_mc_entry) ifv_mc_listhead;
    139 	LIST_ENTRY(ifvlan) ifv_list;
    140 	int ifv_flags;
    141 };
    142 
    143 #define	IFVF_PROMISC	0x01		/* promiscuous mode enabled */
    144 
    145 #define	ifv_ec		ifv_u.ifvu_ec
    146 
    147 #define	ifv_if		ifv_ec.ec_if
    148 
    149 #define	ifv_msw		ifv_mib.ifvm_msw
    150 #define	ifv_encaplen	ifv_mib.ifvm_encaplen
    151 #define	ifv_mtufudge	ifv_mib.ifvm_mtufudge
    152 #define	ifv_mintu	ifv_mib.ifvm_mintu
    153 #define	ifv_tag		ifv_mib.ifvm_tag
    154 
    155 struct vlan_multisw {
    156 	int	(*vmsw_addmulti)(struct ifvlan *, struct ifreq *);
    157 	int	(*vmsw_delmulti)(struct ifvlan *, struct ifreq *);
    158 	void	(*vmsw_purgemulti)(struct ifvlan *);
    159 };
    160 
    161 static int	vlan_ether_addmulti(struct ifvlan *, struct ifreq *);
    162 static int	vlan_ether_delmulti(struct ifvlan *, struct ifreq *);
    163 static void	vlan_ether_purgemulti(struct ifvlan *);
    164 
    165 const struct vlan_multisw vlan_ether_multisw = {
    166 	vlan_ether_addmulti,
    167 	vlan_ether_delmulti,
    168 	vlan_ether_purgemulti,
    169 };
    170 
    171 static int	vlan_clone_create(struct if_clone *, int);
    172 static int	vlan_clone_destroy(struct ifnet *);
    173 static int	vlan_config(struct ifvlan *, struct ifnet *);
    174 static int	vlan_ioctl(struct ifnet *, u_long, void *);
    175 static void	vlan_start(struct ifnet *);
    176 static void	vlan_unconfig(struct ifnet *);
    177 
    178 void		vlanattach(int);
    179 
    180 /* XXX This should be a hash table with the tag as the basis of the key. */
    181 static LIST_HEAD(, ifvlan) ifv_list;
    182 
    183 struct if_clone vlan_cloner =
    184     IF_CLONE_INITIALIZER("vlan", vlan_clone_create, vlan_clone_destroy);
    185 
    186 /* Used to pad ethernet frames with < ETHER_MIN_LEN bytes */
    187 static char vlan_zero_pad_buff[ETHER_MIN_LEN];
    188 
    189 void
    190 vlanattach(int n)
    191 {
    192 
    193 	LIST_INIT(&ifv_list);
    194 	if_clone_attach(&vlan_cloner);
    195 }
    196 
    197 static void
    198 vlan_reset_linkname(struct ifnet *ifp)
    199 {
    200 
    201 	/*
    202 	 * We start out with a "802.1Q VLAN" type and zero-length
    203 	 * addresses.  When we attach to a parent interface, we
    204 	 * inherit its type, address length, address, and data link
    205 	 * type.
    206 	 */
    207 
    208 	ifp->if_type = IFT_L2VLAN;
    209 	ifp->if_addrlen = 0;
    210 	ifp->if_dlt = DLT_NULL;
    211 	if_alloc_sadl(ifp);
    212 }
    213 
    214 static int
    215 vlan_clone_create(struct if_clone *ifc, int unit)
    216 {
    217 	struct ifvlan *ifv;
    218 	struct ifnet *ifp;
    219 	int s;
    220 
    221 	ifv = malloc(sizeof(struct ifvlan), M_DEVBUF, M_WAITOK|M_ZERO);
    222 	ifp = &ifv->ifv_if;
    223 	LIST_INIT(&ifv->ifv_mc_listhead);
    224 
    225 	s = splnet();
    226 	LIST_INSERT_HEAD(&ifv_list, ifv, ifv_list);
    227 	splx(s);
    228 
    229 	if_initname(ifp, ifc->ifc_name, unit);
    230 	ifp->if_softc = ifv;
    231 	ifp->if_flags = IFF_BROADCAST | IFF_SIMPLEX | IFF_MULTICAST;
    232 	ifp->if_start = vlan_start;
    233 	ifp->if_ioctl = vlan_ioctl;
    234 	IFQ_SET_READY(&ifp->if_snd);
    235 
    236 	if_attach(ifp);
    237 	vlan_reset_linkname(ifp);
    238 
    239 	return (0);
    240 }
    241 
    242 static int
    243 vlan_clone_destroy(struct ifnet *ifp)
    244 {
    245 	struct ifvlan *ifv = ifp->if_softc;
    246 	int s;
    247 
    248 	s = splnet();
    249 	LIST_REMOVE(ifv, ifv_list);
    250 	vlan_unconfig(ifp);
    251 	splx(s);
    252 
    253 	if_detach(ifp);
    254 	free(ifv, M_DEVBUF);
    255 
    256 	return (0);
    257 }
    258 
    259 /*
    260  * Configure a VLAN interface.  Must be called at splnet().
    261  */
    262 static int
    263 vlan_config(struct ifvlan *ifv, struct ifnet *p)
    264 {
    265 	struct ifnet *ifp = &ifv->ifv_if;
    266 	int error;
    267 
    268 	if (ifv->ifv_p != NULL)
    269 		return (EBUSY);
    270 
    271 	switch (p->if_type) {
    272 	case IFT_ETHER:
    273 	    {
    274 		struct ethercom *ec = (void *) p;
    275 
    276 		ifv->ifv_msw = &vlan_ether_multisw;
    277 		ifv->ifv_encaplen = ETHER_VLAN_ENCAP_LEN;
    278 		ifv->ifv_mintu = ETHERMIN;
    279 
    280 		/*
    281 		 * If the parent supports the VLAN_MTU capability,
    282 		 * i.e. can Tx/Rx larger than ETHER_MAX_LEN frames,
    283 		 * enable it.
    284 		 */
    285 		if (ec->ec_nvlans++ == 0 &&
    286 		    (ec->ec_capabilities & ETHERCAP_VLAN_MTU) != 0) {
    287 			/*
    288 			 * Enable Tx/Rx of VLAN-sized frames.
    289 			 */
    290 			ec->ec_capenable |= ETHERCAP_VLAN_MTU;
    291 			if (p->if_flags & IFF_UP) {
    292 				struct ifreq ifr;
    293 
    294 				ifr.ifr_flags = p->if_flags;
    295 				error = (*p->if_ioctl)(p, SIOCSIFFLAGS,
    296 				    (void *) &ifr);
    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 			ifp->if_capabilities = p->if_capabilities &
    324 			    (IFCAP_TSOv4 |
    325 			     IFCAP_CSUM_IPv4_Tx|IFCAP_CSUM_IPv4_Rx|
    326 			     IFCAP_CSUM_TCPv4_Tx|IFCAP_CSUM_TCPv4_Rx|
    327 			     IFCAP_CSUM_UDPv4_Tx|IFCAP_CSUM_UDPv4_Rx|
    328 			     IFCAP_CSUM_TCPv6_Tx|IFCAP_CSUM_TCPv6_Rx|
    329 			     IFCAP_CSUM_UDPv6_Tx|IFCAP_CSUM_UDPv6_Rx);
    330 
    331 		/*
    332 		 * We inherit the parent's Ethernet address.
    333 		 */
    334 		ether_ifattach(ifp, CLLADDR(p->if_sadl));
    335 		ifp->if_hdrlen = sizeof(struct ether_vlan_header); /* XXX? */
    336 		break;
    337 	    }
    338 
    339 	default:
    340 		return (EPROTONOSUPPORT);
    341 	}
    342 
    343 	ifv->ifv_p = p;
    344 	ifv->ifv_if.if_mtu = p->if_mtu - ifv->ifv_mtufudge;
    345 	ifv->ifv_if.if_flags = p->if_flags &
    346 	    (IFF_UP | IFF_BROADCAST | IFF_SIMPLEX | IFF_MULTICAST);
    347 
    348 	/*
    349 	 * Inherit the if_type from the parent.  This allows us
    350 	 * to participate in bridges of that type.
    351 	 */
    352 	ifv->ifv_if.if_type = p->if_type;
    353 
    354 	return (0);
    355 }
    356 
    357 /*
    358  * Unconfigure a VLAN interface.  Must be called at splnet().
    359  */
    360 static void
    361 vlan_unconfig(struct ifnet *ifp)
    362 {
    363 	struct ifvlan *ifv = ifp->if_softc;
    364 
    365 	if (ifv->ifv_p == NULL)
    366 		return;
    367 
    368 	/*
    369  	 * Since the interface is being unconfigured, we need to empty the
    370 	 * list of multicast groups that we may have joined while we were
    371 	 * alive and remove them from the parent's list also.
    372 	 */
    373 	(*ifv->ifv_msw->vmsw_purgemulti)(ifv);
    374 
    375 	/* Disconnect from parent. */
    376 	switch (ifv->ifv_p->if_type) {
    377 	case IFT_ETHER:
    378 	    {
    379 		struct ethercom *ec = (void *) ifv->ifv_p;
    380 
    381 		if (ec->ec_nvlans-- == 1) {
    382 			/*
    383 			 * Disable Tx/Rx of VLAN-sized frames.
    384 			 */
    385 			ec->ec_capenable &= ~ETHERCAP_VLAN_MTU;
    386 			if (ifv->ifv_p->if_flags & IFF_UP) {
    387 				struct ifreq ifr;
    388 
    389 				ifr.ifr_flags = ifv->ifv_p->if_flags;
    390 				(void) (*ifv->ifv_p->if_ioctl)(ifv->ifv_p,
    391 				    SIOCSIFFLAGS, (void *) &ifr);
    392 			}
    393 		}
    394 
    395 		ether_ifdetach(ifp);
    396 		vlan_reset_linkname(ifp);
    397 		break;
    398 	    }
    399 
    400 #ifdef DIAGNOSTIC
    401 	default:
    402 		panic("vlan_unconfig: impossible");
    403 #endif
    404 	}
    405 
    406 	ifv->ifv_p = NULL;
    407 	ifv->ifv_if.if_mtu = 0;
    408 	ifv->ifv_flags = 0;
    409 
    410 	if_down(ifp);
    411 	ifp->if_flags &= ~(IFF_UP|IFF_RUNNING);
    412 	ifp->if_capabilities = 0;
    413 }
    414 
    415 /*
    416  * Called when a parent interface is detaching; destroy any VLAN
    417  * configuration for the parent interface.
    418  */
    419 void
    420 vlan_ifdetach(struct ifnet *p)
    421 {
    422 	struct ifvlan *ifv;
    423 	int s;
    424 
    425 	s = splnet();
    426 
    427 	for (ifv = LIST_FIRST(&ifv_list); ifv != NULL;
    428 	     ifv = LIST_NEXT(ifv, ifv_list)) {
    429 		if (ifv->ifv_p == p)
    430 			vlan_unconfig(&ifv->ifv_if);
    431 	}
    432 
    433 	splx(s);
    434 }
    435 
    436 static int
    437 vlan_set_promisc(struct ifnet *ifp)
    438 {
    439 	struct ifvlan *ifv = ifp->if_softc;
    440 	int error = 0;
    441 
    442 	if ((ifp->if_flags & IFF_PROMISC) != 0) {
    443 		if ((ifv->ifv_flags & IFVF_PROMISC) == 0) {
    444 			error = ifpromisc(ifv->ifv_p, 1);
    445 			if (error == 0)
    446 				ifv->ifv_flags |= IFVF_PROMISC;
    447 		}
    448 	} else {
    449 		if ((ifv->ifv_flags & IFVF_PROMISC) != 0) {
    450 			error = ifpromisc(ifv->ifv_p, 0);
    451 			if (error == 0)
    452 				ifv->ifv_flags &= ~IFVF_PROMISC;
    453 		}
    454 	}
    455 
    456 	return (error);
    457 }
    458 
    459 static int
    460 vlan_ioctl(struct ifnet *ifp, u_long cmd, void *data)
    461 {
    462 	struct lwp *l = curlwp;	/* XXX */
    463 	struct ifvlan *ifv = ifp->if_softc;
    464 	struct ifaddr *ifa = (struct ifaddr *) data;
    465 	struct ifreq *ifr = (struct ifreq *) data;
    466 	struct ifnet *pr;
    467 	struct ifcapreq *ifcr;
    468 	struct vlanreq vlr;
    469 	int s, error = 0;
    470 
    471 	s = splnet();
    472 
    473 	switch (cmd) {
    474 	case SIOCINITIFADDR:
    475 		if (ifv->ifv_p != NULL) {
    476 			ifp->if_flags |= IFF_UP;
    477 
    478 			switch (ifa->ifa_addr->sa_family) {
    479 #ifdef INET
    480 			case AF_INET:
    481 				arp_ifinit(ifp, ifa);
    482 				break;
    483 #endif
    484 			default:
    485 				break;
    486 			}
    487 		} else {
    488 			error = EINVAL;
    489 		}
    490 		break;
    491 
    492 	case SIOCSIFMTU:
    493 		if (ifv->ifv_p == NULL)
    494 			error = EINVAL;
    495 		else if (
    496 		    ifr->ifr_mtu > (ifv->ifv_p->if_mtu - ifv->ifv_mtufudge) ||
    497 		    ifr->ifr_mtu < (ifv->ifv_mintu - ifv->ifv_mtufudge))
    498 			error = EINVAL;
    499 		else if ((error = ifioctl_common(ifp, cmd, data)) == ENETRESET)
    500 			error = 0;
    501 		break;
    502 
    503 	case SIOCSETVLAN:
    504 		if ((error = kauth_authorize_network(l->l_cred,
    505 		    KAUTH_NETWORK_INTERFACE,
    506 		    KAUTH_REQ_NETWORK_INTERFACE_SETPRIV, ifp, (void *)cmd,
    507 		    NULL)) != 0)
    508 			break;
    509 		if ((error = copyin(ifr->ifr_data, &vlr, sizeof(vlr))) != 0)
    510 			break;
    511 		if (vlr.vlr_parent[0] == '\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 	default:
    575 		error = ether_ioctl(ifp, cmd, data);
    576 	}
    577 
    578 	splx(s);
    579 
    580 	return (error);
    581 }
    582 
    583 static int
    584 vlan_ether_addmulti(struct ifvlan *ifv, struct ifreq *ifr)
    585 {
    586 	const struct sockaddr *sa = ifreq_getaddr(SIOCADDMULTI, ifr);
    587 	struct vlan_mc_entry *mc;
    588 	uint8_t addrlo[ETHER_ADDR_LEN], addrhi[ETHER_ADDR_LEN];
    589 	int error;
    590 
    591 	if (sa->sa_len > sizeof(struct sockaddr_storage))
    592 		return (EINVAL);
    593 
    594 	error = ether_addmulti(sa, &ifv->ifv_ec);
    595 	if (error != ENETRESET)
    596 		return (error);
    597 
    598 	/*
    599 	 * This is new multicast address.  We have to tell parent
    600 	 * about it.  Also, remember this multicast address so that
    601 	 * we can delete them on unconfigure.
    602 	 */
    603 	mc = malloc(sizeof(struct vlan_mc_entry), M_DEVBUF, M_NOWAIT);
    604 	if (mc == NULL) {
    605 		error = ENOMEM;
    606 		goto alloc_failed;
    607 	}
    608 
    609 	/*
    610 	 * As ether_addmulti() returns ENETRESET, following two
    611 	 * statement shouldn't fail.
    612 	 */
    613 	(void)ether_multiaddr(sa, addrlo, addrhi);
    614 	ETHER_LOOKUP_MULTI(addrlo, addrhi, &ifv->ifv_ec, mc->mc_enm);
    615 	memcpy(&mc->mc_addr, sa, sa->sa_len);
    616 	LIST_INSERT_HEAD(&ifv->ifv_mc_listhead, mc, mc_entries);
    617 
    618 	error = (*ifv->ifv_p->if_ioctl)(ifv->ifv_p, SIOCADDMULTI,
    619 	    (void *)ifr);
    620 	if (error != 0)
    621 		goto ioctl_failed;
    622 	return (error);
    623 
    624  ioctl_failed:
    625 	LIST_REMOVE(mc, mc_entries);
    626 	free(mc, M_DEVBUF);
    627  alloc_failed:
    628 	(void)ether_delmulti(sa, &ifv->ifv_ec);
    629 	return (error);
    630 }
    631 
    632 static int
    633 vlan_ether_delmulti(struct ifvlan *ifv, struct ifreq *ifr)
    634 {
    635 	const struct sockaddr *sa = ifreq_getaddr(SIOCDELMULTI, ifr);
    636 	struct ether_multi *enm;
    637 	struct vlan_mc_entry *mc;
    638 	uint8_t addrlo[ETHER_ADDR_LEN], addrhi[ETHER_ADDR_LEN];
    639 	int error;
    640 
    641 	/*
    642 	 * Find a key to lookup vlan_mc_entry.  We have to do this
    643 	 * before calling ether_delmulti for obvious reason.
    644 	 */
    645 	if ((error = ether_multiaddr(sa, addrlo, addrhi)) != 0)
    646 		return (error);
    647 	ETHER_LOOKUP_MULTI(addrlo, addrhi, &ifv->ifv_ec, enm);
    648 
    649 	error = ether_delmulti(sa, &ifv->ifv_ec);
    650 	if (error != ENETRESET)
    651 		return (error);
    652 
    653 	/* We no longer use this multicast address.  Tell parent so. */
    654 	error = (*ifv->ifv_p->if_ioctl)(ifv->ifv_p, SIOCDELMULTI,
    655 	    (void *)ifr);
    656 	if (error == 0) {
    657 		/* And forget about this address. */
    658 		for (mc = LIST_FIRST(&ifv->ifv_mc_listhead); mc != NULL;
    659 		    mc = LIST_NEXT(mc, mc_entries)) {
    660 			if (mc->mc_enm == enm) {
    661 				LIST_REMOVE(mc, mc_entries);
    662 				free(mc, M_DEVBUF);
    663 				break;
    664 			}
    665 		}
    666 		KASSERT(mc != NULL);
    667 	} else
    668 		(void)ether_addmulti(sa, &ifv->ifv_ec);
    669 	return (error);
    670 }
    671 
    672 /*
    673  * Delete any multicast address we have asked to add from parent
    674  * interface.  Called when the vlan is being unconfigured.
    675  */
    676 static void
    677 vlan_ether_purgemulti(struct ifvlan *ifv)
    678 {
    679 	struct ifnet *ifp = ifv->ifv_p;		/* Parent. */
    680 	struct vlan_mc_entry *mc;
    681 	union {
    682 		struct ifreq ifreq;
    683 		struct {
    684 			char ifr_name[IFNAMSIZ];
    685 			struct sockaddr_storage ifr_ss;
    686 		} ifreq_storage;
    687 	} ifreq;
    688 	struct ifreq *ifr = &ifreq.ifreq;
    689 
    690 	memcpy(ifr->ifr_name, ifp->if_xname, IFNAMSIZ);
    691 	while ((mc = LIST_FIRST(&ifv->ifv_mc_listhead)) != NULL) {
    692 		ifreq_setaddr(SIOCDELMULTI, ifr,
    693 		    (const struct sockaddr *)&mc->mc_addr);
    694 		(void)(*ifp->if_ioctl)(ifp, SIOCDELMULTI, (void *)ifr);
    695 		LIST_REMOVE(mc, mc_entries);
    696 		free(mc, M_DEVBUF);
    697 	}
    698 }
    699 
    700 static void
    701 vlan_start(struct ifnet *ifp)
    702 {
    703 	struct ifvlan *ifv = ifp->if_softc;
    704 	struct ifnet *p = ifv->ifv_p;
    705 	struct ethercom *ec = (void *) ifv->ifv_p;
    706 	struct mbuf *m;
    707 	int error;
    708 	ALTQ_DECL(struct altq_pktattr pktattr;)
    709 
    710 	ifp->if_flags |= IFF_OACTIVE;
    711 
    712 	for (;;) {
    713 		IFQ_DEQUEUE(&ifp->if_snd, m);
    714 		if (m == NULL)
    715 			break;
    716 
    717 #ifdef ALTQ
    718 		/*
    719 		 * If ALTQ is enabled on the parent interface, do
    720 		 * classification; the queueing discipline might
    721 		 * not require classification, but might require
    722 		 * the address family/header pointer in the pktattr.
    723 		 */
    724 		if (ALTQ_IS_ENABLED(&p->if_snd)) {
    725 			switch (p->if_type) {
    726 			case IFT_ETHER:
    727 				altq_etherclassify(&p->if_snd, m, &pktattr);
    728 				break;
    729 #ifdef DIAGNOSTIC
    730 			default:
    731 				panic("vlan_start: impossible (altq)");
    732 #endif
    733 			}
    734 		}
    735 #endif /* ALTQ */
    736 
    737 #if NBPFILTER > 0
    738 		if (ifp->if_bpf)
    739 			bpf_mtap(ifp->if_bpf, m);
    740 #endif
    741 		/*
    742 		 * If the parent can insert the tag itself, just mark
    743 		 * the tag in the mbuf header.
    744 		 */
    745 		if (ec->ec_capabilities & ETHERCAP_VLAN_HWTAGGING) {
    746 			struct m_tag *mtag;
    747 
    748 			mtag = m_tag_get(PACKET_TAG_VLAN, sizeof(u_int),
    749 			    M_NOWAIT);
    750 			if (mtag == NULL) {
    751 				ifp->if_oerrors++;
    752 				m_freem(m);
    753 				continue;
    754 			}
    755 			*(u_int *)(mtag + 1) = ifv->ifv_tag;
    756 			m_tag_prepend(m, mtag);
    757 		} else {
    758 			/*
    759 			 * insert the tag ourselves
    760 			 */
    761 			M_PREPEND(m, ifv->ifv_encaplen, M_DONTWAIT);
    762 			if (m == NULL) {
    763 				printf("%s: unable to prepend encap header",
    764 				    ifv->ifv_p->if_xname);
    765 				ifp->if_oerrors++;
    766 				continue;
    767 			}
    768 
    769 			switch (p->if_type) {
    770 			case IFT_ETHER:
    771 			    {
    772 				struct ether_vlan_header *evl;
    773 
    774 				if (m->m_len < sizeof(struct ether_vlan_header))
    775 					m = m_pullup(m,
    776 					    sizeof(struct ether_vlan_header));
    777 				if (m == NULL) {
    778 					printf("%s: unable to pullup encap "
    779 					    "header", ifv->ifv_p->if_xname);
    780 					ifp->if_oerrors++;
    781 					continue;
    782 				}
    783 
    784 				/*
    785 				 * Transform the Ethernet header into an
    786 				 * Ethernet header with 802.1Q encapsulation.
    787 				 */
    788 				memmove(mtod(m, void *),
    789 				    mtod(m, char *) + ifv->ifv_encaplen,
    790 				    sizeof(struct ether_header));
    791 				evl = mtod(m, struct ether_vlan_header *);
    792 				evl->evl_proto = evl->evl_encap_proto;
    793 				evl->evl_encap_proto = htons(ETHERTYPE_VLAN);
    794 				evl->evl_tag = htons(ifv->ifv_tag);
    795 
    796 				/*
    797 				 * To cater for VLAN-aware layer 2 ethernet
    798 				 * switches which may need to strip the tag
    799 				 * before forwarding the packet, make sure
    800 				 * the packet+tag is at least 68 bytes long.
    801 				 * This is necessary because our parent will
    802 				 * only pad to 64 bytes (ETHER_MIN_LEN) and
    803 				 * some switches will not pad by themselves
    804 				 * after deleting a tag.
    805 				 */
    806 				if (m->m_pkthdr.len <
    807 				    (ETHER_MIN_LEN + ETHER_VLAN_ENCAP_LEN)) {
    808 					m_copyback(m, m->m_pkthdr.len,
    809 					    (ETHER_MIN_LEN +
    810 					     ETHER_VLAN_ENCAP_LEN) -
    811 					     m->m_pkthdr.len,
    812 					    vlan_zero_pad_buff);
    813 				}
    814 				break;
    815 			    }
    816 
    817 #ifdef DIAGNOSTIC
    818 			default:
    819 				panic("vlan_start: impossible");
    820 #endif
    821 			}
    822 		}
    823 
    824 		/*
    825 		 * Send it, precisely as the parent's output routine
    826 		 * would have.  We are already running at splnet.
    827 		 */
    828 		IFQ_ENQUEUE(&p->if_snd, m, &pktattr, error);
    829 		if (error) {
    830 			/* mbuf is already freed */
    831 			ifp->if_oerrors++;
    832 			continue;
    833 		}
    834 
    835 		ifp->if_opackets++;
    836 		if ((p->if_flags & (IFF_RUNNING|IFF_OACTIVE)) == IFF_RUNNING)
    837 			(*p->if_start)(p);
    838 	}
    839 
    840 	ifp->if_flags &= ~IFF_OACTIVE;
    841 }
    842 
    843 /*
    844  * Given an Ethernet frame, find a valid vlan interface corresponding to the
    845  * given source interface and tag, then run the real packet through the
    846  * parent's input routine.
    847  */
    848 void
    849 vlan_input(struct ifnet *ifp, struct mbuf *m)
    850 {
    851 	struct ifvlan *ifv;
    852 	u_int tag;
    853 	struct m_tag *mtag;
    854 
    855 	mtag = m_tag_find(m, PACKET_TAG_VLAN, NULL);
    856 	if (mtag != NULL) {
    857 		/* m contains a normal ethernet frame, the tag is in mtag */
    858 		tag = EVL_VLANOFTAG(*(u_int *)(mtag + 1));
    859 		m_tag_delete(m, mtag);
    860 	} else {
    861 		switch (ifp->if_type) {
    862 		case IFT_ETHER:
    863 		    {
    864 			struct ether_vlan_header *evl;
    865 
    866 			if (m->m_len < sizeof(struct ether_vlan_header) &&
    867 			    (m = m_pullup(m,
    868 			     sizeof(struct ether_vlan_header))) == NULL) {
    869 				printf("%s: no memory for VLAN header, "
    870 				    "dropping packet.\n", ifp->if_xname);
    871 				return;
    872 			}
    873 			evl = mtod(m, struct ether_vlan_header *);
    874 			KASSERT(ntohs(evl->evl_encap_proto) == ETHERTYPE_VLAN);
    875 
    876 			tag = EVL_VLANOFTAG(ntohs(evl->evl_tag));
    877 
    878 			/*
    879 			 * Restore the original ethertype.  We'll remove
    880 			 * the encapsulation after we've found the vlan
    881 			 * interface corresponding to the tag.
    882 			 */
    883 			evl->evl_encap_proto = evl->evl_proto;
    884 			break;
    885 		    }
    886 
    887 		default:
    888 			tag = (u_int) -1;	/* XXX GCC */
    889 #ifdef DIAGNOSTIC
    890 			panic("vlan_input: impossible");
    891 #endif
    892 		}
    893 	}
    894 
    895 	for (ifv = LIST_FIRST(&ifv_list); ifv != NULL;
    896 	    ifv = LIST_NEXT(ifv, ifv_list))
    897 		if (ifp == ifv->ifv_p && tag == ifv->ifv_tag)
    898 			break;
    899 
    900 	if (ifv == NULL ||
    901 	    (ifv->ifv_if.if_flags & (IFF_UP|IFF_RUNNING)) !=
    902 	     (IFF_UP|IFF_RUNNING)) {
    903 		m_freem(m);
    904 		ifp->if_noproto++;
    905 		return;
    906 	}
    907 
    908 	/*
    909 	 * Now, remove the encapsulation header.  The original
    910 	 * header has already been fixed up above.
    911 	 */
    912 	if (mtag == NULL) {
    913 		memmove(mtod(m, char *) + ifv->ifv_encaplen,
    914 		    mtod(m, void *), sizeof(struct ether_header));
    915 		m_adj(m, ifv->ifv_encaplen);
    916 	}
    917 
    918 	m->m_pkthdr.rcvif = &ifv->ifv_if;
    919 	ifv->ifv_if.if_ipackets++;
    920 
    921 #if NBPFILTER > 0
    922 	if (ifv->ifv_if.if_bpf)
    923 		bpf_mtap(ifv->ifv_if.if_bpf, m);
    924 #endif
    925 
    926 	/* Pass it back through the parent's input routine. */
    927 	(*ifp->if_input)(&ifv->ifv_if, m);
    928 }
    929