/* $OpenBSD: if_bpe.c,v 1.20 2023/10/27 20:56:47 jan Exp $ */ /* * Copyright (c) 2018 David Gwynne * * Permission to use, copy, modify, and distribute this software for any * purpose with or without fee is hereby granted, provided that the above * copyright notice and this permission notice appear in all copies. * * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. */ #include "bpfilter.h" #include "pf.h" #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include /* for bridge stuff */ #include #include #if NBPFILTER > 0 #include #endif #include #define PBB_ITAG_ISID 0x00ffffff #define PBB_ITAG_ISID_MIN 0x00000000 #define PBB_ITAG_ISID_MAX 0x00ffffff #define PBB_ITAG_RES2 0x03000000 /* must be zero on input */ #define PBB_ITAG_RES1 0x04000000 /* ignore on input */ #define PBB_ITAG_UCA 0x08000000 #define PBB_ITAG_DEI 0x10000000 #define PBB_ITAG_PCP_SHIFT 29 #define PBB_ITAG_PCP_MASK (0x7U << PBB_ITAG_PCP_SHIFT) #define BPE_BRIDGE_AGE_TMO 100 /* seconds */ struct bpe_key { int k_if; uint32_t k_isid; RBT_ENTRY(bpe_tunnel) k_entry; }; RBT_HEAD(bpe_tree, bpe_key); static inline int bpe_cmp(const struct bpe_key *, const struct bpe_key *); RBT_PROTOTYPE(bpe_tree, bpe_key, k_entry, bpe_cmp); RBT_GENERATE(bpe_tree, bpe_key, k_entry, bpe_cmp); struct bpe_softc { struct bpe_key sc_key; /* must be first */ struct arpcom sc_ac; int sc_txhprio; int sc_rxhprio; struct ether_addr sc_group; struct task sc_ltask; struct task sc_dtask; struct etherbridge sc_eb; }; void bpeattach(int); static int bpe_clone_create(struct if_clone *, int); static int bpe_clone_destroy(struct ifnet *); static void bpe_start(struct ifnet *); static int bpe_ioctl(struct ifnet *, u_long, caddr_t); static int bpe_media_get(struct bpe_softc *, struct ifreq *); static int bpe_up(struct bpe_softc *); static int bpe_down(struct bpe_softc *); static int bpe_multi(struct bpe_softc *, struct ifnet *, u_long); static int bpe_set_vnetid(struct bpe_softc *, const struct ifreq *); static void bpe_set_group(struct bpe_softc *, uint32_t); static int bpe_set_parent(struct bpe_softc *, const struct if_parent *); static int bpe_get_parent(struct bpe_softc *, struct if_parent *); static int bpe_del_parent(struct bpe_softc *); static int bpe_add_addr(struct bpe_softc *, const struct ifbareq *); static int bpe_del_addr(struct bpe_softc *, const struct ifbareq *); static void bpe_link_hook(void *); static void bpe_link_state(struct bpe_softc *, u_char, uint64_t); static void bpe_detach_hook(void *); static struct if_clone bpe_cloner = IF_CLONE_INITIALIZER("bpe", bpe_clone_create, bpe_clone_destroy); static int bpe_eb_port_eq(void *, void *, void *); static void *bpe_eb_port_take(void *, void *); static void bpe_eb_port_rele(void *, void *); static size_t bpe_eb_port_ifname(void *, char *, size_t, void *); static void bpe_eb_port_sa(void *, struct sockaddr_storage *, void *); static const struct etherbridge_ops bpe_etherbridge_ops = { bpe_eb_port_eq, bpe_eb_port_take, bpe_eb_port_rele, bpe_eb_port_ifname, bpe_eb_port_sa, }; static struct bpe_tree bpe_interfaces = RBT_INITIALIZER(); static struct rwlock bpe_lock = RWLOCK_INITIALIZER("bpeifs"); static struct pool bpe_endpoint_pool; void bpeattach(int count) { if_clone_attach(&bpe_cloner); } static int bpe_clone_create(struct if_clone *ifc, int unit) { struct bpe_softc *sc; struct ifnet *ifp; int error; if (bpe_endpoint_pool.pr_size == 0) { pool_init(&bpe_endpoint_pool, sizeof(struct ether_addr), 0, IPL_NONE, 0, "bpepl", NULL); } sc = malloc(sizeof(*sc), M_DEVBUF, M_WAITOK|M_ZERO); ifp = &sc->sc_ac.ac_if; snprintf(ifp->if_xname, sizeof(ifp->if_xname), "%s%d", ifc->ifc_name, unit); error = etherbridge_init(&sc->sc_eb, ifp->if_xname, &bpe_etherbridge_ops, sc); if (error == -1) { free(sc, M_DEVBUF, sizeof(*sc)); return (error); } sc->sc_key.k_if = 0; sc->sc_key.k_isid = 0; bpe_set_group(sc, 0); sc->sc_txhprio = IF_HDRPRIO_PACKET; sc->sc_rxhprio = IF_HDRPRIO_OUTER; task_set(&sc->sc_ltask, bpe_link_hook, sc); task_set(&sc->sc_dtask, bpe_detach_hook, sc); ifp->if_softc = sc; ifp->if_hardmtu = ETHER_MAX_HARDMTU_LEN; ifp->if_ioctl = bpe_ioctl; ifp->if_start = bpe_start; ifp->if_flags = IFF_BROADCAST | IFF_MULTICAST; ifp->if_xflags = IFXF_CLONED; ether_fakeaddr(ifp); if_counters_alloc(ifp); if_attach(ifp); ether_ifattach(ifp); return (0); } static int bpe_clone_destroy(struct ifnet *ifp) { struct bpe_softc *sc = ifp->if_softc; NET_LOCK(); if (ISSET(ifp->if_flags, IFF_RUNNING)) bpe_down(sc); NET_UNLOCK(); ether_ifdetach(ifp); if_detach(ifp); etherbridge_destroy(&sc->sc_eb); free(sc, M_DEVBUF, sizeof(*sc)); return (0); } static void bpe_start(struct ifnet *ifp) { struct bpe_softc *sc = ifp->if_softc; struct ifnet *ifp0; struct mbuf *m0, *m; struct ether_header *ceh; struct ether_header *beh; uint32_t itag, *itagp; int hlen = sizeof(*beh) + sizeof(*itagp); #if NBPFILTER > 0 caddr_t if_bpf; #endif int txprio; uint8_t prio; ifp0 = if_get(sc->sc_key.k_if); if (ifp0 == NULL || !ISSET(ifp0->if_flags, IFF_RUNNING)) { ifq_purge(&ifp->if_snd); goto done; } txprio = sc->sc_txhprio; while ((m0 = ifq_dequeue(&ifp->if_snd)) != NULL) { #if NBPFILTER > 0 if_bpf = ifp->if_bpf; if (if_bpf) bpf_mtap_ether(if_bpf, m0, BPF_DIRECTION_OUT); #endif ceh = mtod(m0, struct ether_header *); /* force prepend of a whole mbuf because of alignment */ m = m_get(M_DONTWAIT, m0->m_type); if (m == NULL) { m_freem(m0); continue; } M_MOVE_PKTHDR(m, m0); m->m_next = m0; m_align(m, 0); m->m_len = 0; m = m_prepend(m, hlen, M_DONTWAIT); if (m == NULL) continue; beh = mtod(m, struct ether_header *); if (ETHER_IS_BROADCAST(ceh->ether_dhost)) { memcpy(beh->ether_dhost, &sc->sc_group, sizeof(beh->ether_dhost)); } else { struct ether_addr *endpoint; smr_read_enter(); endpoint = etherbridge_resolve_ea(&sc->sc_eb, (struct ether_addr *)ceh->ether_dhost); if (endpoint == NULL) { /* "flood" to unknown hosts */ endpoint = &sc->sc_group; } memcpy(beh->ether_dhost, endpoint, sizeof(beh->ether_dhost)); smr_read_leave(); } memcpy(beh->ether_shost, ((struct arpcom *)ifp0)->ac_enaddr, sizeof(beh->ether_shost)); beh->ether_type = htons(ETHERTYPE_PBB); prio = (txprio == IF_HDRPRIO_PACKET) ? m->m_pkthdr.pf.prio : txprio; itag = sc->sc_key.k_isid; itag |= prio << PBB_ITAG_PCP_SHIFT; itagp = (uint32_t *)(beh + 1); htobem32(itagp, itag); if_enqueue(ifp0, m); } done: if_put(ifp0); } static int bpe_ioctl(struct ifnet *ifp, u_long cmd, caddr_t data) { struct bpe_softc *sc = ifp->if_softc; struct ifreq *ifr = (struct ifreq *)data; struct ifbrparam *bparam = (struct ifbrparam *)data; int error = 0; switch (cmd) { case SIOCSIFFLAGS: if (ISSET(ifp->if_flags, IFF_UP)) { if (!ISSET(ifp->if_flags, IFF_RUNNING)) error = bpe_up(sc); else error = 0; } else { if (ISSET(ifp->if_flags, IFF_RUNNING)) error = bpe_down(sc); } break; case SIOCSVNETID: error = bpe_set_vnetid(sc, ifr); break; case SIOCGVNETID: ifr->ifr_vnetid = sc->sc_key.k_isid; break; case SIOCSIFPARENT: error = bpe_set_parent(sc, (struct if_parent *)data); break; case SIOCGIFPARENT: error = bpe_get_parent(sc, (struct if_parent *)data); break; case SIOCDIFPARENT: error = bpe_del_parent(sc); break; case SIOCSTXHPRIO: error = if_txhprio_l2_check(ifr->ifr_hdrprio); if (error != 0) break; sc->sc_txhprio = ifr->ifr_hdrprio; break; case SIOCGTXHPRIO: ifr->ifr_hdrprio = sc->sc_txhprio; break; case SIOCSRXHPRIO: error = if_rxhprio_l2_check(ifr->ifr_hdrprio); if (error != 0) break; sc->sc_rxhprio = ifr->ifr_hdrprio; break; case SIOCGRXHPRIO: ifr->ifr_hdrprio = sc->sc_rxhprio; break; case SIOCGIFMEDIA: error = bpe_media_get(sc, ifr); break; case SIOCBRDGSCACHE: error = suser(curproc); if (error != 0) break; error = etherbridge_set_max(&sc->sc_eb, bparam); break; case SIOCBRDGGCACHE: error = etherbridge_get_max(&sc->sc_eb, bparam); break; case SIOCBRDGSTO: error = suser(curproc); if (error != 0) break; error = etherbridge_set_tmo(&sc->sc_eb, bparam); break; case SIOCBRDGGTO: error = etherbridge_get_tmo(&sc->sc_eb, bparam); break; case SIOCBRDGRTS: error = etherbridge_rtfind(&sc->sc_eb, (struct ifbaconf *)data); break; case SIOCBRDGFLUSH: error = suser(curproc); if (error != 0) break; etherbridge_flush(&sc->sc_eb, ((struct ifbreq *)data)->ifbr_ifsflags); break; case SIOCBRDGSADDR: error = bpe_add_addr(sc, (struct ifbareq *)data); break; case SIOCBRDGDADDR: error = bpe_del_addr(sc, (struct ifbareq *)data); break; default: error = ether_ioctl(ifp, &sc->sc_ac, cmd, data); break; } return (error); } static int bpe_media_get(struct bpe_softc *sc, struct ifreq *ifr) { struct ifnet *ifp0; int error; ifp0 = if_get(sc->sc_key.k_if); if (ifp0 != NULL) error = (*ifp0->if_ioctl)(ifp0, SIOCGIFMEDIA, (caddr_t)ifr); else error = ENOTTY; if_put(ifp0); return (error); } static int bpe_up(struct bpe_softc *sc) { struct ifnet *ifp = &sc->sc_ac.ac_if; struct ifnet *ifp0; struct bpe_softc *osc; int error; u_int hardmtu; u_int hlen = sizeof(struct ether_header) + sizeof(uint32_t); KASSERT(!ISSET(ifp->if_flags, IFF_RUNNING)); NET_ASSERT_LOCKED(); error = etherbridge_up(&sc->sc_eb); if (error != 0) return (error); ifp0 = if_get(sc->sc_key.k_if); if (ifp0 == NULL) { error = ENXIO; goto down; } /* check again if bpe will work on top of the parent */ if (ifp0->if_type != IFT_ETHER) { error = EPROTONOSUPPORT; goto put; } hardmtu = ifp0->if_hardmtu; if (hardmtu < hlen) { error = ENOBUFS; goto put; } hardmtu -= hlen; if (ifp->if_mtu > hardmtu) { error = ENOBUFS; goto put; } /* parent is fine, let's prepare the bpe to handle packets */ ifp->if_hardmtu = hardmtu; SET(ifp->if_flags, ifp0->if_flags & IFF_SIMPLEX); /* commit the interface */ error = rw_enter(&bpe_lock, RW_WRITE | RW_INTR); if (error != 0) goto scrub; osc = (struct bpe_softc *)RBT_INSERT(bpe_tree, &bpe_interfaces, (struct bpe_key *)sc); rw_exit(&bpe_lock); if (osc != NULL) { error = EADDRINUSE; goto scrub; } if (bpe_multi(sc, ifp0, SIOCADDMULTI) != 0) { error = ENOTCONN; goto remove; } /* Register callback for physical link state changes */ if_linkstatehook_add(ifp0, &sc->sc_ltask); /* Register callback if parent wants to unregister */ if_detachhook_add(ifp0, &sc->sc_dtask); /* we're running now */ SET(ifp->if_flags, IFF_RUNNING); bpe_link_state(sc, ifp0->if_link_state, ifp0->if_baudrate); if_put(ifp0); return (0); remove: rw_enter(&bpe_lock, RW_WRITE); RBT_REMOVE(bpe_tree, &bpe_interfaces, (struct bpe_key *)sc); rw_exit(&bpe_lock); scrub: CLR(ifp->if_flags, IFF_SIMPLEX); ifp->if_hardmtu = 0xffff; put: if_put(ifp0); down: etherbridge_down(&sc->sc_eb); return (error); } static int bpe_down(struct bpe_softc *sc) { struct ifnet *ifp = &sc->sc_ac.ac_if; struct ifnet *ifp0; NET_ASSERT_LOCKED(); CLR(ifp->if_flags, IFF_RUNNING); ifp0 = if_get(sc->sc_key.k_if); if (ifp0 != NULL) { if_detachhook_del(ifp0, &sc->sc_dtask); if_linkstatehook_del(ifp0, &sc->sc_ltask); bpe_multi(sc, ifp0, SIOCDELMULTI); } if_put(ifp0); rw_enter(&bpe_lock, RW_WRITE); RBT_REMOVE(bpe_tree, &bpe_interfaces, (struct bpe_key *)sc); rw_exit(&bpe_lock); CLR(ifp->if_flags, IFF_SIMPLEX); ifp->if_hardmtu = 0xffff; etherbridge_down(&sc->sc_eb); return (0); } static int bpe_multi(struct bpe_softc *sc, struct ifnet *ifp0, u_long cmd) { struct ifreq ifr; struct sockaddr *sa; /* make it convincing */ CTASSERT(sizeof(ifr.ifr_name) == sizeof(ifp0->if_xname)); memcpy(ifr.ifr_name, ifp0->if_xname, sizeof(ifr.ifr_name)); sa = &ifr.ifr_addr; CTASSERT(sizeof(sa->sa_data) >= sizeof(sc->sc_group)); sa->sa_family = AF_UNSPEC; memcpy(sa->sa_data, &sc->sc_group, sizeof(sc->sc_group)); return ((*ifp0->if_ioctl)(ifp0, cmd, (caddr_t)&ifr)); } static void bpe_set_group(struct bpe_softc *sc, uint32_t isid) { uint8_t *group = sc->sc_group.ether_addr_octet; group[0] = 0x01; group[1] = 0x1e; group[2] = 0x83; group[3] = isid >> 16; group[4] = isid >> 8; group[5] = isid >> 0; } static int bpe_set_vnetid(struct bpe_softc *sc, const struct ifreq *ifr) { struct ifnet *ifp = &sc->sc_ac.ac_if; uint32_t isid; if (ifr->ifr_vnetid < PBB_ITAG_ISID_MIN || ifr->ifr_vnetid > PBB_ITAG_ISID_MAX) return (EINVAL); isid = ifr->ifr_vnetid; if (isid == sc->sc_key.k_isid) return (0); if (ISSET(ifp->if_flags, IFF_RUNNING)) return (EBUSY); /* commit */ sc->sc_key.k_isid = isid; bpe_set_group(sc, isid); etherbridge_flush(&sc->sc_eb, IFBF_FLUSHALL); return (0); } static int bpe_set_parent(struct bpe_softc *sc, const struct if_parent *p) { struct ifnet *ifp = &sc->sc_ac.ac_if; struct ifnet *ifp0; int error = 0; ifp0 = if_unit(p->ifp_parent); if (ifp0 == NULL) return (ENXIO); if (ifp0->if_type != IFT_ETHER) { error = ENXIO; goto put; } if (ifp0->if_index == sc->sc_key.k_if) goto put; if (ISSET(ifp->if_flags, IFF_RUNNING)) { error = EBUSY; goto put; } ifsetlro(ifp0, 0); /* commit */ sc->sc_key.k_if = ifp0->if_index; etherbridge_flush(&sc->sc_eb, IFBF_FLUSHALL); put: if_put(ifp0); return (error); } static int bpe_get_parent(struct bpe_softc *sc, struct if_parent *p) { struct ifnet *ifp0; int error = 0; ifp0 = if_get(sc->sc_key.k_if); if (ifp0 == NULL) error = EADDRNOTAVAIL; else memcpy(p->ifp_parent, ifp0->if_xname, sizeof(p->ifp_parent)); if_put(ifp0); return (error); } static int bpe_del_parent(struct bpe_softc *sc) { struct ifnet *ifp = &sc->sc_ac.ac_if; if (ISSET(ifp->if_flags, IFF_RUNNING)) return (EBUSY); /* commit */ sc->sc_key.k_if = 0; etherbridge_flush(&sc->sc_eb, IFBF_FLUSHALL); return (0); } static int bpe_add_addr(struct bpe_softc *sc, const struct ifbareq *ifba) { const struct sockaddr_dl *sdl; const struct ether_addr *endpoint; unsigned int type; /* ignore ifba_ifsname */ if (ISSET(ifba->ifba_flags, ~IFBAF_TYPEMASK)) return (EINVAL); switch (ifba->ifba_flags & IFBAF_TYPEMASK) { case IFBAF_DYNAMIC: type = EBE_DYNAMIC; break; case IFBAF_STATIC: type = EBE_STATIC; break; default: return (EINVAL); } if (ifba->ifba_dstsa.ss_family != AF_LINK) return (EAFNOSUPPORT); sdl = (struct sockaddr_dl *)&ifba->ifba_dstsa; if (sdl->sdl_type != IFT_ETHER) return (EAFNOSUPPORT); if (sdl->sdl_alen != ETHER_ADDR_LEN) return (EINVAL); endpoint = (struct ether_addr *)LLADDR(sdl); /* check endpoint for multicast or broadcast? */ return (etherbridge_add_addr(&sc->sc_eb, (void *)endpoint, &ifba->ifba_dst, type)); } static int bpe_del_addr(struct bpe_softc *sc, const struct ifbareq *ifba) { return (etherbridge_del_addr(&sc->sc_eb, &ifba->ifba_dst)); } static inline struct bpe_softc * bpe_find(struct ifnet *ifp0, uint32_t isid) { struct bpe_key k = { .k_if = ifp0->if_index, .k_isid = isid }; struct bpe_softc *sc; rw_enter_read(&bpe_lock); sc = (struct bpe_softc *)RBT_FIND(bpe_tree, &bpe_interfaces, &k); rw_exit_read(&bpe_lock); return (sc); } void bpe_input(struct ifnet *ifp0, struct mbuf *m) { struct bpe_softc *sc; struct ifnet *ifp; struct ether_header *beh, *ceh; uint32_t *itagp, itag; unsigned int hlen = sizeof(*beh) + sizeof(*itagp) + sizeof(*ceh); struct mbuf *n; int off; int prio; if (m->m_len < hlen) { m = m_pullup(m, hlen); if (m == NULL) { /* pbb short ++ */ return; } } beh = mtod(m, struct ether_header *); itagp = (uint32_t *)(beh + 1); itag = bemtoh32(itagp); if (itag & PBB_ITAG_RES2) { /* dropped by res2 ++ */ goto drop; } sc = bpe_find(ifp0, itag & PBB_ITAG_ISID); if (sc == NULL) { /* no interface found */ goto drop; } ceh = (struct ether_header *)(itagp + 1); etherbridge_map_ea(&sc->sc_eb, ceh->ether_shost, (struct ether_addr *)beh->ether_shost); m_adj(m, sizeof(*beh) + sizeof(*itagp)); n = m_getptr(m, sizeof(*ceh), &off); if (n == NULL) { /* no data ++ */ goto drop; } if (!ALIGNED_POINTER(mtod(n, caddr_t) + off, uint32_t)) { /* unaligned ++ */ n = m_dup_pkt(m, ETHER_ALIGN, M_NOWAIT); m_freem(m); if (n == NULL) return; m = n; } ifp = &sc->sc_ac.ac_if; prio = sc->sc_rxhprio; switch (prio) { case IF_HDRPRIO_PACKET: break; case IF_HDRPRIO_OUTER: m->m_pkthdr.pf.prio = (itag & PBB_ITAG_PCP_MASK) >> PBB_ITAG_PCP_SHIFT; break; default: m->m_pkthdr.pf.prio = prio; break; } m->m_flags &= ~(M_BCAST|M_MCAST); m->m_pkthdr.ph_ifidx = ifp->if_index; m->m_pkthdr.ph_rtableid = ifp->if_rdomain; #if NPF > 0 pf_pkt_addr_changed(m); #endif if_vinput(ifp, m); return; drop: m_freem(m); } void bpe_detach_hook(void *arg) { struct bpe_softc *sc = arg; struct ifnet *ifp = &sc->sc_ac.ac_if; if (ISSET(ifp->if_flags, IFF_RUNNING)) { bpe_down(sc); CLR(ifp->if_flags, IFF_UP); } sc->sc_key.k_if = 0; } static void bpe_link_hook(void *arg) { struct bpe_softc *sc = arg; struct ifnet *ifp0; u_char link = LINK_STATE_DOWN; uint64_t baud = 0; ifp0 = if_get(sc->sc_key.k_if); if (ifp0 != NULL) { link = ifp0->if_link_state; baud = ifp0->if_baudrate; } if_put(ifp0); bpe_link_state(sc, link, baud); } void bpe_link_state(struct bpe_softc *sc, u_char link, uint64_t baud) { struct ifnet *ifp = &sc->sc_ac.ac_if; if (ifp->if_link_state == link) return; ifp->if_link_state = link; ifp->if_baudrate = baud; if_link_state_change(ifp); } static inline int bpe_cmp(const struct bpe_key *a, const struct bpe_key *b) { if (a->k_if > b->k_if) return (1); if (a->k_if < b->k_if) return (-1); if (a->k_isid > b->k_isid) return (1); if (a->k_isid < b->k_isid) return (-1); return (0); } static int bpe_eb_port_eq(void *arg, void *a, void *b) { struct ether_addr *ea = a, *eb = b; return (memcmp(ea, eb, sizeof(*ea)) == 0); } static void * bpe_eb_port_take(void *arg, void *port) { struct ether_addr *ea = port; struct ether_addr *endpoint; endpoint = pool_get(&bpe_endpoint_pool, PR_NOWAIT); if (endpoint == NULL) return (NULL); memcpy(endpoint, ea, sizeof(*endpoint)); return (endpoint); } static void bpe_eb_port_rele(void *arg, void *port) { struct ether_addr *endpoint = port; pool_put(&bpe_endpoint_pool, endpoint); } static size_t bpe_eb_port_ifname(void *arg, char *dst, size_t len, void *port) { struct bpe_softc *sc = arg; return (strlcpy(dst, sc->sc_ac.ac_if.if_xname, len)); } static void bpe_eb_port_sa(void *arg, struct sockaddr_storage *ss, void *port) { struct ether_addr *endpoint = port; struct sockaddr_dl *sdl; sdl = (struct sockaddr_dl *)ss; sdl->sdl_len = sizeof(sdl); sdl->sdl_family = AF_LINK; sdl->sdl_index = 0; sdl->sdl_type = IFT_ETHER; sdl->sdl_nlen = 0; sdl->sdl_alen = sizeof(*endpoint); CTASSERT(sizeof(sdl->sdl_data) >= sizeof(*endpoint)); memcpy(sdl->sdl_data, endpoint, sizeof(*endpoint)); }