/* $OpenBSD: if_vlan.c,v 1.112 2015/02/06 08:07:09 henning Exp $ */ /* * Copyright 1998 Massachusetts Institute of Technology * * Permission to use, copy, modify, and distribute this software and * its documentation for any purpose and without fee is hereby * granted, provided that both the above copyright notice and this * permission notice appear in all copies, that both the above * copyright notice and this permission notice appear in all * supporting documentation, and that the name of M.I.T. not be used * in advertising or publicity pertaining to distribution of the * software without specific, written prior permission. M.I.T. makes * no representations about the suitability of this software for any * purpose. It is provided "as is" without express or implied * warranty. * * THIS SOFTWARE IS PROVIDED BY M.I.T. ``AS IS''. M.I.T. DISCLAIMS * ALL EXPRESS OR IMPLIED WARRANTIES WITH REGARD TO THIS SOFTWARE, * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT * SHALL M.I.T. BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * * $FreeBSD: src/sys/net/if_vlan.c,v 1.16 2000/03/26 15:21:40 charnier Exp $ */ /* * if_vlan.c - pseudo-device driver for IEEE 802.1Q virtual LANs. * This is sort of sneaky in the implementation, since * we need to pretend to be enough of an Ethernet implementation * to make arp work. The way we do this is by telling everyone * that we are an Ethernet, and then catch the packets that * ether_output() left on our output queue when it calls * if_start(), rewrite them for use by the real outgoing interface, * and ask it to send them. * * Some devices support 802.1Q tag insertion in firmware. The * vlan interface behavior changes when the IFCAP_VLAN_HWTAGGING * capability is set on the parent. In this case, vlan_start() * will not modify the ethernet header. */ #include "vlan.h" #include #include #include #include #include #include #include #include #include "bpfilter.h" #if NBPFILTER > 0 #include #endif #include #include #include #include #include #include u_long vlan_tagmask, svlan_tagmask; #define TAG_HASH_SIZE 32 #define TAG_HASH(tag) (tag & vlan_tagmask) LIST_HEAD(vlan_taghash, ifvlan) *vlan_tagh, *svlan_tagh; int vlan_output(struct ifnet *, struct mbuf *, struct sockaddr *, struct rtentry *); void vlan_start(struct ifnet *ifp); int vlan_ioctl(struct ifnet *ifp, u_long cmd, caddr_t addr); int vlan_unconfig(struct ifnet *ifp, struct ifnet *newp); int vlan_config(struct ifvlan *, struct ifnet *, u_int16_t); void vlan_vlandev_state(void *); void vlanattach(int count); int vlan_set_promisc(struct ifnet *ifp); int vlan_ether_addmulti(struct ifvlan *, struct ifreq *); int vlan_ether_delmulti(struct ifvlan *, struct ifreq *); void vlan_ether_purgemulti(struct ifvlan *); void vlan_ether_resetmulti(struct ifvlan *, struct ifnet *); int vlan_clone_create(struct if_clone *, int); int vlan_clone_destroy(struct ifnet *); void vlan_ifdetach(void *); struct if_clone vlan_cloner = IF_CLONE_INITIALIZER("vlan", vlan_clone_create, vlan_clone_destroy); struct if_clone svlan_cloner = IF_CLONE_INITIALIZER("svlan", vlan_clone_create, vlan_clone_destroy); /* ARGSUSED */ void vlanattach(int count) { /* Normal VLAN */ vlan_tagh = hashinit(TAG_HASH_SIZE, M_DEVBUF, M_NOWAIT, &vlan_tagmask); if (vlan_tagh == NULL) panic("vlanattach: hashinit"); if_clone_attach(&vlan_cloner); /* Service-VLAN for QinQ/802.1ad provider bridges */ svlan_tagh = hashinit(TAG_HASH_SIZE, M_DEVBUF, M_NOWAIT, &svlan_tagmask); if (svlan_tagh == NULL) panic("vlanattach: hashinit"); if_clone_attach(&svlan_cloner); } int vlan_clone_create(struct if_clone *ifc, int unit) { struct ifvlan *ifv; struct ifnet *ifp; if ((ifv = malloc(sizeof(*ifv), M_DEVBUF, M_NOWAIT|M_ZERO)) == NULL) return (ENOMEM); LIST_INIT(&ifv->vlan_mc_listhead); ifp = &ifv->ifv_if; ifp->if_softc = ifv; snprintf(ifp->if_xname, sizeof ifp->if_xname, "%s%d", ifc->ifc_name, unit); /* NB: flags are not set here */ /* NB: mtu is not set here */ /* Special handling for the IEEE 802.1ad QinQ variant */ if (strcmp("svlan", ifc->ifc_name) == 0) ifv->ifv_type = ETHERTYPE_QINQ; else ifv->ifv_type = ETHERTYPE_VLAN; ifp->if_start = vlan_start; ifp->if_ioctl = vlan_ioctl; IFQ_SET_MAXLEN(&ifp->if_snd, 1); IFQ_SET_READY(&ifp->if_snd); if_attach(ifp); ether_ifattach(ifp); ifp->if_hdrlen = EVL_ENCAPLEN; ifp->if_output = vlan_output; return (0); } int vlan_clone_destroy(struct ifnet *ifp) { struct ifvlan *ifv = ifp->if_softc; vlan_unconfig(ifp, NULL); ether_ifdetach(ifp); if_detach(ifp); free(ifv, M_DEVBUF, sizeof(*ifv)); return (0); } void vlan_ifdetach(void *ptr) { struct ifvlan *ifv = ptr; vlan_clone_destroy(&ifv->ifv_if); } int vlan_output(struct ifnet *ifp, struct mbuf *m, struct sockaddr *dst, struct rtentry *rt) { /* * we have to use a custom output function because ether_output * can't figure out ifp is a vlan in a reasonable way */ m->m_flags |= M_VLANTAG; return (ether_output(ifp, m, dst, rt)); } void vlan_start(struct ifnet *ifp) { struct ifvlan *ifv; struct ifnet *p; struct mbuf *m; int error; ifv = ifp->if_softc; p = ifv->ifv_p; for (;;) { IFQ_DEQUEUE(&ifp->if_snd, m); if (m == NULL) break; if ((p->if_flags & (IFF_UP|IFF_RUNNING)) != (IFF_UP|IFF_RUNNING)) { IF_DROP(&p->if_snd); ifp->if_oerrors++; m_freem(m); continue; } #if NBPFILTER > 0 if (ifp->if_bpf) { if ((p->if_capabilities & IFCAP_VLAN_HWTAGGING) && (ifv->ifv_type == ETHERTYPE_VLAN)) bpf_mtap(ifp->if_bpf, m, BPF_DIRECTION_OUT); else { struct mbuf *m0; u_int off; struct m_hdr mh; struct { uint8_t dst[ETHER_ADDR_LEN]; uint8_t src[ETHER_ADDR_LEN]; } hdr; /* copy the ether addresses off the front */ m_copydata(m, 0, sizeof(hdr), (caddr_t)&hdr); /* find the ethertype after the vlan subhdr*/ m0 = m_getptr(m, offsetof(struct ether_vlan_header, evl_proto), &off); KASSERT(m0 != NULL); /* pretend the vlan subhdr isnt there */ mh.mh_flags = 0; mh.mh_data = mtod(m0, caddr_t) + off; mh.mh_len = m0->m_len - off; mh.mh_next = m0->m_next; /* dst+src + ethertype == ethernet header */ bpf_mtap_hdr(ifp->if_bpf, (caddr_t)&hdr, sizeof(hdr), (struct mbuf *)&mh, BPF_DIRECTION_OUT, NULL); } } #endif /* NBPFILTER > 0 */ /* * Send it, precisely as ether_output() would have. * We are already running at splnet. */ IFQ_ENQUEUE(&p->if_snd, m, NULL, error); if (error) { /* mbuf is already freed */ ifp->if_oerrors++; continue; } p->if_obytes += m->m_pkthdr.len; if (m->m_flags & M_MCAST) p->if_omcasts++; ifp->if_opackets++; if_start(p); } } /* * vlan_input() returns 0 if it has consumed the packet, 1 otherwise. */ int vlan_input(struct ether_header *eh, struct mbuf *m) { struct ifvlan *ifv; struct ifnet *ifp = m->m_pkthdr.rcvif; struct vlan_taghash *tagh; u_int tag; u_int16_t etype; if (m->m_flags & M_VLANTAG) { etype = ETHERTYPE_VLAN; tagh = vlan_tagh; } else { if (m->m_len < EVL_ENCAPLEN && (m = m_pullup(m, EVL_ENCAPLEN)) == NULL) { ifp->if_ierrors++; return (0); } etype = ntohs(eh->ether_type); tagh = etype == ETHERTYPE_QINQ ? svlan_tagh : vlan_tagh; m->m_pkthdr.ether_vtag = ntohs(*mtod(m, u_int16_t *)); } /* From now on ether_vtag is fine */ tag = EVL_VLANOFTAG(m->m_pkthdr.ether_vtag); m->m_pkthdr.pf.prio = EVL_PRIOFTAG(m->m_pkthdr.ether_vtag); /* IEEE 802.1p has prio 0 and 1 swapped */ if (m->m_pkthdr.pf.prio <= 1) m->m_pkthdr.pf.prio = !m->m_pkthdr.pf.prio; LIST_FOREACH(ifv, &tagh[TAG_HASH(tag)], ifv_list) { if (m->m_pkthdr.rcvif == ifv->ifv_p && tag == ifv->ifv_tag && etype == ifv->ifv_type) break; } if (ifv == NULL) return (1); if ((ifv->ifv_if.if_flags & (IFF_UP|IFF_RUNNING)) != (IFF_UP|IFF_RUNNING)) { m_freem(m); return (0); } /* * Having found a valid vlan interface corresponding to * the given source interface and vlan tag, remove the * encapsulation, and run the real packet through * ether_input() a second time (it had better be * reentrant!). */ m->m_pkthdr.rcvif = &ifv->ifv_if; if (m->m_flags & M_VLANTAG) { m->m_flags &= ~M_VLANTAG; } else { eh->ether_type = mtod(m, u_int16_t *)[1]; m->m_len -= EVL_ENCAPLEN; m->m_data += EVL_ENCAPLEN; m->m_pkthdr.len -= EVL_ENCAPLEN; } #if NBPFILTER > 0 if (ifv->ifv_if.if_bpf) bpf_mtap_hdr(ifv->ifv_if.if_bpf, (char *)eh, ETHER_HDR_LEN, m, BPF_DIRECTION_IN, NULL); #endif /* * Drop promiscuously received packets if we are not in * promiscuous mode. */ if ((m->m_flags & (M_BCAST|M_MCAST)) == 0 && (ifp->if_flags & IFF_PROMISC) && (ifv->ifv_if.if_flags & IFF_PROMISC) == 0) { if (bcmp(&ifv->ifv_ac.ac_enaddr, eh->ether_dhost, ETHER_ADDR_LEN)) { m_freem(m); return (0); } } ifv->ifv_if.if_ipackets++; ether_input(&ifv->ifv_if, eh, m); return (0); } int vlan_config(struct ifvlan *ifv, struct ifnet *p, u_int16_t tag) { struct sockaddr_dl *sdl1, *sdl2; struct vlan_taghash *tagh; u_int flags; int s; if (p->if_type != IFT_ETHER) return EPROTONOSUPPORT; if (ifv->ifv_p == p && ifv->ifv_tag == tag) /* noop */ return (0); /* Remember existing interface flags and reset the interface */ flags = ifv->ifv_flags; vlan_unconfig(&ifv->ifv_if, p); ifv->ifv_p = p; ifv->ifv_if.if_baudrate = p->if_baudrate; if (p->if_capabilities & IFCAP_VLAN_MTU) ifv->ifv_if.if_mtu = p->if_mtu; else ifv->ifv_if.if_mtu = p->if_mtu - EVL_ENCAPLEN; ifv->ifv_if.if_flags = p->if_flags & (IFF_UP | IFF_BROADCAST | IFF_SIMPLEX | IFF_MULTICAST); /* Reset promisc mode on the interface and its parent */ if (flags & IFVF_PROMISC) { ifv->ifv_if.if_flags |= IFF_PROMISC; vlan_set_promisc(&ifv->ifv_if); } /* * If the parent interface can do hardware-assisted * VLAN encapsulation, then propagate its hardware- * assisted checksumming flags. * * If the card cannot handle hardware tagging, it cannot * possibly compute the correct checksums for tagged packets. */ if (p->if_capabilities & IFCAP_VLAN_HWTAGGING) ifv->ifv_if.if_capabilities = p->if_capabilities & IFCAP_CSUM_MASK; /* * Hardware VLAN tagging only works with the default VLAN * ethernet type (0x8100). */ if (ifv->ifv_type != ETHERTYPE_VLAN) ifv->ifv_if.if_capabilities &= ~IFCAP_VLAN_HWTAGGING; /* * Set up our ``Ethernet address'' to reflect the underlying * physical interface's. */ sdl1 = ifv->ifv_if.if_sadl; sdl2 = p->if_sadl; sdl1->sdl_type = IFT_ETHER; sdl1->sdl_alen = ETHER_ADDR_LEN; bcopy(LLADDR(sdl2), LLADDR(sdl1), ETHER_ADDR_LEN); bcopy(LLADDR(sdl2), ifv->ifv_ac.ac_enaddr, ETHER_ADDR_LEN); ifv->ifv_tag = tag; s = splnet(); tagh = ifv->ifv_type == ETHERTYPE_QINQ ? svlan_tagh : vlan_tagh; LIST_INSERT_HEAD(&tagh[TAG_HASH(tag)], ifv, ifv_list); /* Register callback for physical link state changes */ ifv->lh_cookie = hook_establish(p->if_linkstatehooks, 1, vlan_vlandev_state, ifv); /* Register callback if parent wants to unregister */ ifv->dh_cookie = hook_establish(p->if_detachhooks, 0, vlan_ifdetach, ifv); vlan_vlandev_state(ifv); splx(s); return (0); } int vlan_unconfig(struct ifnet *ifp, struct ifnet *newp) { struct sockaddr_dl *sdl; struct ifvlan *ifv; struct ifnet *p; int s; ifv = ifp->if_softc; if ((p = ifv->ifv_p) == NULL) return 0; /* Unset promisc mode on the interface and its parent */ if (ifv->ifv_flags & IFVF_PROMISC) { ifp->if_flags &= ~IFF_PROMISC; vlan_set_promisc(ifp); } s = splnet(); LIST_REMOVE(ifv, ifv_list); splx(s); hook_disestablish(p->if_linkstatehooks, ifv->lh_cookie); hook_disestablish(p->if_detachhooks, ifv->dh_cookie); /* Reset link state */ if (newp != NULL) { ifp->if_link_state = LINK_STATE_INVALID; if_link_state_change(ifp); } /* * Since the interface is being unconfigured, we need to * empty the list of multicast groups that we may have joined * while we were alive and remove them from the parent's list * as well. */ vlan_ether_resetmulti(ifv, newp); /* Disconnect from parent. */ ifv->ifv_p = NULL; ifv->ifv_if.if_mtu = ETHERMTU; ifv->ifv_flags = 0; /* Clear our MAC address. */ sdl = ifv->ifv_if.if_sadl; sdl->sdl_type = IFT_ETHER; sdl->sdl_alen = ETHER_ADDR_LEN; bzero(LLADDR(sdl), ETHER_ADDR_LEN); bzero(ifv->ifv_ac.ac_enaddr, ETHER_ADDR_LEN); return (0); } void vlan_vlandev_state(void *v) { struct ifvlan *ifv = v; if (ifv->ifv_if.if_link_state == ifv->ifv_p->if_link_state) return; ifv->ifv_if.if_link_state = ifv->ifv_p->if_link_state; ifv->ifv_if.if_baudrate = ifv->ifv_p->if_baudrate; if_link_state_change(&ifv->ifv_if); } int vlan_set_promisc(struct ifnet *ifp) { struct ifvlan *ifv = ifp->if_softc; int error = 0; if ((ifp->if_flags & IFF_PROMISC) != 0) { if ((ifv->ifv_flags & IFVF_PROMISC) == 0) if ((error = ifpromisc(ifv->ifv_p, 1)) == 0) ifv->ifv_flags |= IFVF_PROMISC; } else { if ((ifv->ifv_flags & IFVF_PROMISC) != 0) if ((error = ifpromisc(ifv->ifv_p, 0)) == 0) ifv->ifv_flags &= ~IFVF_PROMISC; } return (0); } int vlan_ioctl(struct ifnet *ifp, u_long cmd, caddr_t data) { struct proc *p = curproc; /* XXX */ struct ifaddr *ifa; struct ifnet *pr; struct ifreq *ifr; struct ifvlan *ifv; struct vlanreq vlr; int error = 0, p_mtu = 0, s; ifr = (struct ifreq *)data; ifa = (struct ifaddr *)data; ifv = ifp->if_softc; switch (cmd) { case SIOCSIFADDR: if (ifv->ifv_p != NULL) { ifp->if_flags |= IFF_UP; if (ifa->ifa_addr->sa_family == AF_INET) arp_ifinit(&ifv->ifv_ac, ifa); } else error = EINVAL; break; case SIOCGIFADDR: { struct sockaddr *sa; sa = (struct sockaddr *)&ifr->ifr_data; bcopy(((struct arpcom *)ifp->if_softc)->ac_enaddr, (caddr_t) sa->sa_data, ETHER_ADDR_LEN); } break; case SIOCSIFMTU: if (ifv->ifv_p != NULL) { if (ifv->ifv_p->if_capabilities & IFCAP_VLAN_MTU) p_mtu = ifv->ifv_p->if_mtu; else p_mtu = ifv->ifv_p->if_mtu - EVL_ENCAPLEN; if (ifr->ifr_mtu > p_mtu || ifr->ifr_mtu < ETHERMIN) error = EINVAL; else ifp->if_mtu = ifr->ifr_mtu; } else error = EINVAL; break; case SIOCSETVLAN: if ((error = suser(p, 0)) != 0) break; if ((error = copyin(ifr->ifr_data, &vlr, sizeof vlr))) break; if (vlr.vlr_parent[0] == '\0') { s = splnet(); vlan_unconfig(ifp, NULL); if (ifp->if_flags & IFF_UP) if_down(ifp); ifp->if_flags &= ~IFF_RUNNING; splx(s); break; } pr = ifunit(vlr.vlr_parent); if (pr == NULL) { error = ENOENT; break; } /* * Don't let the caller set up a VLAN tag with * anything except VLID bits. */ if (vlr.vlr_tag & ~EVL_VLID_MASK) { error = EINVAL; break; } error = vlan_config(ifv, pr, vlr.vlr_tag); if (error) break; ifp->if_flags |= IFF_RUNNING; /* Update promiscuous mode, if necessary. */ vlan_set_promisc(ifp); break; case SIOCGETVLAN: bzero(&vlr, sizeof vlr); if (ifv->ifv_p) { snprintf(vlr.vlr_parent, sizeof(vlr.vlr_parent), "%s", ifv->ifv_p->if_xname); vlr.vlr_tag = ifv->ifv_tag; } error = copyout(&vlr, ifr->ifr_data, sizeof vlr); break; case SIOCSIFFLAGS: /* * For promiscuous mode, we enable promiscuous mode on * the parent if we need promiscuous on the VLAN interface. */ if (ifv->ifv_p != NULL) error = vlan_set_promisc(ifp); break; case SIOCADDMULTI: error = (ifv->ifv_p != NULL) ? vlan_ether_addmulti(ifv, ifr) : EINVAL; break; case SIOCDELMULTI: error = (ifv->ifv_p != NULL) ? vlan_ether_delmulti(ifv, ifr) : EINVAL; break; default: error = ENOTTY; } return error; } int vlan_ether_addmulti(struct ifvlan *ifv, struct ifreq *ifr) { struct ifnet *ifp = ifv->ifv_p; struct vlan_mc_entry *mc; u_int8_t addrlo[ETHER_ADDR_LEN], addrhi[ETHER_ADDR_LEN]; int error; error = ether_addmulti(ifr, (struct arpcom *)&ifv->ifv_ac); if (error != ENETRESET) return (error); /* * This is new multicast address. We have to tell parent * about it. Also, remember this multicast address so that * we can delete them on unconfigure. */ if ((mc = malloc(sizeof(*mc), M_DEVBUF, M_NOWAIT)) == NULL) { error = ENOMEM; goto alloc_failed; } /* * As ether_addmulti() returns ENETRESET, following two * statement shouldn't fail. */ (void)ether_multiaddr(&ifr->ifr_addr, addrlo, addrhi); ETHER_LOOKUP_MULTI(addrlo, addrhi, &ifv->ifv_ac, mc->mc_enm); memcpy(&mc->mc_addr, &ifr->ifr_addr, ifr->ifr_addr.sa_len); LIST_INSERT_HEAD(&ifv->vlan_mc_listhead, mc, mc_entries); if ((error = (*ifp->if_ioctl)(ifp, SIOCADDMULTI, (caddr_t)ifr)) != 0) goto ioctl_failed; return (error); ioctl_failed: LIST_REMOVE(mc, mc_entries); free(mc, M_DEVBUF, 0); alloc_failed: (void)ether_delmulti(ifr, (struct arpcom *)&ifv->ifv_ac); return (error); } int vlan_ether_delmulti(struct ifvlan *ifv, struct ifreq *ifr) { struct ifnet *ifp = ifv->ifv_p; struct ether_multi *enm; struct vlan_mc_entry *mc; u_int8_t addrlo[ETHER_ADDR_LEN], addrhi[ETHER_ADDR_LEN]; int error; /* * Find a key to lookup vlan_mc_entry. We have to do this * before calling ether_delmulti for obvious reason. */ if ((error = ether_multiaddr(&ifr->ifr_addr, addrlo, addrhi)) != 0) return (error); ETHER_LOOKUP_MULTI(addrlo, addrhi, &ifv->ifv_ac, enm); if (enm == NULL) return (EINVAL); LIST_FOREACH(mc, &ifv->vlan_mc_listhead, mc_entries) if (mc->mc_enm == enm) break; /* We won't delete entries we didn't add */ if (mc == NULL) return (EINVAL); if ((error = ether_delmulti(ifr, (struct arpcom *)&ifv->ifv_ac)) != 0) return (error); /* We no longer use this multicast address. Tell parent so. */ if ((error = (*ifp->if_ioctl)(ifp, SIOCDELMULTI, (caddr_t)ifr)) != 0) { /* And forget about this address. */ LIST_REMOVE(mc, mc_entries); free(mc, M_DEVBUF, 0); } else (void)ether_addmulti(ifr, (struct arpcom *)&ifv->ifv_ac); return (error); } /* * Delete any multicast address we have asked to add from parent * interface. Called when the vlan is being unconfigured. */ void vlan_ether_purgemulti(struct ifvlan *ifv) { struct ifnet *ifp = ifv->ifv_p; struct vlan_mc_entry *mc; union { struct ifreq ifreq; struct { char ifr_name[IFNAMSIZ]; struct sockaddr_storage ifr_ss; } ifreq_storage; } ifreq; struct ifreq *ifr = &ifreq.ifreq; memcpy(ifr->ifr_name, ifp->if_xname, IFNAMSIZ); while ((mc = LIST_FIRST(&ifv->vlan_mc_listhead)) != NULL) { memcpy(&ifr->ifr_addr, &mc->mc_addr, mc->mc_addr.ss_len); (void)(*ifp->if_ioctl)(ifp, SIOCDELMULTI, (caddr_t)ifr); LIST_REMOVE(mc, mc_entries); free(mc, M_DEVBUF, 0); } } void vlan_ether_resetmulti(struct ifvlan *ifv, struct ifnet *p) { struct ifnet *ifp = ifv->ifv_p; struct vlan_mc_entry *mc; union { struct ifreq ifreq; struct { char ifr_name[IFNAMSIZ]; struct sockaddr_storage ifr_ss; } ifreq_storage; } ifreq; struct ifreq *ifr = &ifreq.ifreq; if (p == NULL) { vlan_ether_purgemulti(ifv); return; } else if (ifp == p) return; LIST_FOREACH(mc, &ifv->vlan_mc_listhead, mc_entries) { memcpy(&ifr->ifr_addr, &mc->mc_addr, mc->mc_addr.ss_len); /* Remove from the old parent */ memcpy(ifr->ifr_name, ifp->if_xname, IFNAMSIZ); (void)(*ifp->if_ioctl)(ifp, SIOCDELMULTI, (caddr_t)ifr); /* Try to add to the new parent */ memcpy(ifr->ifr_name, p->if_xname, IFNAMSIZ); (void)(*p->if_ioctl)(p, SIOCADDMULTI, (caddr_t)ifr); } }