/*- * SPDX-License-Identifier: BSD-3-Clause * * Copyright (c) 1982, 1989, 1993 * The Regents of the University of California. All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS 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. * * @(#)if_ethersubr.c 8.1 (Berkeley) 6/10/93 * $FreeBSD$ */ #include "opt_inet.h" #include "opt_inet6.h" #include "opt_netgraph.h" #include "opt_mbuf_profiling.h" #include "opt_rss.h" #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #if defined(INET) || defined(INET6) #include #include #include #include #include #endif #ifdef INET6 #include #endif #include #include #ifdef CTASSERT CTASSERT(sizeof (struct ether_header) == ETHER_ADDR_LEN * 2 + 2); CTASSERT(sizeof (struct ether_addr) == ETHER_ADDR_LEN); #endif VNET_DEFINE(pfil_head_t, link_pfil_head); /* Packet filter hooks */ /* netgraph node hooks for ng_ether(4) */ void (*ng_ether_input_p)(struct ifnet *ifp, struct mbuf **mp); void (*ng_ether_input_orphan_p)(struct ifnet *ifp, struct mbuf *m); int (*ng_ether_output_p)(struct ifnet *ifp, struct mbuf **mp); void (*ng_ether_attach_p)(struct ifnet *ifp); void (*ng_ether_detach_p)(struct ifnet *ifp); void (*vlan_input_p)(struct ifnet *, struct mbuf *); /* if_bridge(4) support */ void (*bridge_dn_p)(struct mbuf *, struct ifnet *); /* if_lagg(4) support */ struct mbuf *(*lagg_input_ethernet_p)(struct ifnet *, struct mbuf *); static const u_char etherbroadcastaddr[ETHER_ADDR_LEN] = { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff }; static int ether_resolvemulti(struct ifnet *, struct sockaddr **, struct sockaddr *); static int ether_requestencap(struct ifnet *, struct if_encap_req *); #define senderr(e) do { error = (e); goto bad;} while (0) static void update_mbuf_csumflags(struct mbuf *src, struct mbuf *dst) { int csum_flags = 0; if (src->m_pkthdr.csum_flags & CSUM_IP) csum_flags |= (CSUM_IP_CHECKED|CSUM_IP_VALID); if (src->m_pkthdr.csum_flags & CSUM_DELAY_DATA) csum_flags |= (CSUM_DATA_VALID|CSUM_PSEUDO_HDR); if (src->m_pkthdr.csum_flags & CSUM_SCTP) csum_flags |= CSUM_SCTP_VALID; dst->m_pkthdr.csum_flags |= csum_flags; if (csum_flags & CSUM_DATA_VALID) dst->m_pkthdr.csum_data = 0xffff; } /* * Handle link-layer encapsulation requests. */ static int ether_requestencap(struct ifnet *ifp, struct if_encap_req *req) { struct ether_header *eh; struct arphdr *ah; uint16_t etype; const u_char *lladdr; if (req->rtype != IFENCAP_LL) return (EOPNOTSUPP); if (req->bufsize < ETHER_HDR_LEN) return (ENOMEM); eh = (struct ether_header *)req->buf; lladdr = req->lladdr; req->lladdr_off = 0; switch (req->family) { case AF_INET: etype = htons(ETHERTYPE_IP); break; case AF_INET6: etype = htons(ETHERTYPE_IPV6); break; case AF_ARP: ah = (struct arphdr *)req->hdata; ah->ar_hrd = htons(ARPHRD_ETHER); switch(ntohs(ah->ar_op)) { case ARPOP_REVREQUEST: case ARPOP_REVREPLY: etype = htons(ETHERTYPE_REVARP); break; case ARPOP_REQUEST: case ARPOP_REPLY: default: etype = htons(ETHERTYPE_ARP); break; } if (req->flags & IFENCAP_FLAG_BROADCAST) lladdr = ifp->if_broadcastaddr; break; default: return (EAFNOSUPPORT); } memcpy(&eh->ether_type, &etype, sizeof(eh->ether_type)); memcpy(eh->ether_dhost, lladdr, ETHER_ADDR_LEN); memcpy(eh->ether_shost, IF_LLADDR(ifp), ETHER_ADDR_LEN); req->bufsize = sizeof(struct ether_header); return (0); } static int ether_resolve_addr(struct ifnet *ifp, struct mbuf *m, const struct sockaddr *dst, struct route *ro, u_char *phdr, uint32_t *pflags, struct llentry **plle) { struct ether_header *eh; uint32_t lleflags = 0; int error = 0; #if defined(INET) || defined(INET6) uint16_t etype; #endif if (plle) *plle = NULL; eh = (struct ether_header *)phdr; switch (dst->sa_family) { #ifdef INET case AF_INET: if ((m->m_flags & (M_BCAST | M_MCAST)) == 0) error = arpresolve(ifp, 0, m, dst, phdr, &lleflags, plle); else { if (m->m_flags & M_BCAST) memcpy(eh->ether_dhost, ifp->if_broadcastaddr, ETHER_ADDR_LEN); else { const struct in_addr *a; a = &(((const struct sockaddr_in *)dst)->sin_addr); ETHER_MAP_IP_MULTICAST(a, eh->ether_dhost); } etype = htons(ETHERTYPE_IP); memcpy(&eh->ether_type, &etype, sizeof(etype)); memcpy(eh->ether_shost, IF_LLADDR(ifp), ETHER_ADDR_LEN); } break; #endif #ifdef INET6 case AF_INET6: if ((m->m_flags & M_MCAST) == 0) error = nd6_resolve(ifp, 0, m, dst, phdr, &lleflags, plle); else { const struct in6_addr *a6; a6 = &(((const struct sockaddr_in6 *)dst)->sin6_addr); ETHER_MAP_IPV6_MULTICAST(a6, eh->ether_dhost); etype = htons(ETHERTYPE_IPV6); memcpy(&eh->ether_type, &etype, sizeof(etype)); memcpy(eh->ether_shost, IF_LLADDR(ifp), ETHER_ADDR_LEN); } break; #endif default: if_printf(ifp, "can't handle af%d\n", dst->sa_family); if (m != NULL) m_freem(m); return (EAFNOSUPPORT); } if (error == EHOSTDOWN) { if (ro != NULL && (ro->ro_flags & RT_HAS_GW) != 0) error = EHOSTUNREACH; } if (error != 0) return (error); *pflags = RT_MAY_LOOP; if (lleflags & LLE_IFADDR) *pflags |= RT_L2_ME; return (0); } /* * Ethernet output routine. * Encapsulate a packet of type family for the local net. * Use trailer local net encapsulation if enough data in first * packet leaves a multiple of 512 bytes of data in remainder. */ int ether_output(struct ifnet *ifp, struct mbuf *m, const struct sockaddr *dst, struct route *ro) { int error = 0; char linkhdr[ETHER_HDR_LEN], *phdr; struct ether_header *eh; struct pf_mtag *t; bool loop_copy; int hlen; /* link layer header length */ uint32_t pflags; struct llentry *lle = NULL; int addref = 0; phdr = NULL; pflags = 0; if (ro != NULL) { /* XXX BPF uses ro_prepend */ if (ro->ro_prepend != NULL) { phdr = ro->ro_prepend; hlen = ro->ro_plen; } else if (!(m->m_flags & (M_BCAST | M_MCAST))) { if ((ro->ro_flags & RT_LLE_CACHE) != 0) { lle = ro->ro_lle; if (lle != NULL && (lle->la_flags & LLE_VALID) == 0) { LLE_FREE(lle); lle = NULL; /* redundant */ ro->ro_lle = NULL; } if (lle == NULL) { /* if we lookup, keep cache */ addref = 1; } else /* * Notify LLE code that * the entry was used * by datapath. */ llentry_mark_used(lle); } if (lle != NULL) { phdr = lle->r_linkdata; hlen = lle->r_hdrlen; pflags = lle->r_flags; } } } #ifdef MAC error = mac_ifnet_check_transmit(ifp, m); if (error) senderr(error); #endif M_PROFILE(m); if (ifp->if_flags & IFF_MONITOR) senderr(ENETDOWN); if (!((ifp->if_flags & IFF_UP) && (ifp->if_drv_flags & IFF_DRV_RUNNING))) senderr(ENETDOWN); if (phdr == NULL) { /* No prepend data supplied. Try to calculate ourselves. */ phdr = linkhdr; hlen = ETHER_HDR_LEN; error = ether_resolve_addr(ifp, m, dst, ro, phdr, &pflags, addref ? &lle : NULL); if (addref && lle != NULL) ro->ro_lle = lle; if (error != 0) return (error == EWOULDBLOCK ? 0 : error); } if ((pflags & RT_L2_ME) != 0) { update_mbuf_csumflags(m, m); return (if_simloop(ifp, m, dst->sa_family, 0)); } loop_copy = (pflags & RT_MAY_LOOP) != 0; /* * Add local net header. If no space in first mbuf, * allocate another. * * Note that we do prepend regardless of RT_HAS_HEADER flag. * This is done because BPF code shifts m_data pointer * to the end of ethernet header prior to calling if_output(). */ M_PREPEND(m, hlen, M_NOWAIT); if (m == NULL) senderr(ENOBUFS); if ((pflags & RT_HAS_HEADER) == 0) { eh = mtod(m, struct ether_header *); memcpy(eh, phdr, hlen); } /* * If a simplex interface, and the packet is being sent to our * Ethernet address or a broadcast address, loopback a copy. * XXX To make a simplex device behave exactly like a duplex * device, we should copy in the case of sending to our own * ethernet address (thus letting the original actually appear * on the wire). However, we don't do that here for security * reasons and compatibility with the original behavior. */ if ((m->m_flags & M_BCAST) && loop_copy && (ifp->if_flags & IFF_SIMPLEX) && ((t = pf_find_mtag(m)) == NULL || !t->routed)) { struct mbuf *n; /* * Because if_simloop() modifies the packet, we need a * writable copy through m_dup() instead of a readonly * one as m_copy[m] would give us. The alternative would * be to modify if_simloop() to handle the readonly mbuf, * but performancewise it is mostly equivalent (trading * extra data copying vs. extra locking). * * XXX This is a local workaround. A number of less * often used kernel parts suffer from the same bug. * See PR kern/105943 for a proposed general solution. */ if ((n = m_dup(m, M_NOWAIT)) != NULL) { update_mbuf_csumflags(m, n); (void)if_simloop(ifp, n, dst->sa_family, hlen); } else if_inc_counter(ifp, IFCOUNTER_IQDROPS, 1); } /* * Bridges require special output handling. */ if (ifp->if_bridge) { BRIDGE_OUTPUT(ifp, m, error); return (error); } #if defined(INET) || defined(INET6) if (ifp->if_carp && (error = (*carp_output_p)(ifp, m, dst))) goto bad; #endif /* Handle ng_ether(4) processing, if any */ if (ifp->if_l2com != NULL) { KASSERT(ng_ether_output_p != NULL, ("ng_ether_output_p is NULL")); if ((error = (*ng_ether_output_p)(ifp, &m)) != 0) { bad: if (m != NULL) m_freem(m); return (error); } if (m == NULL) return (0); } /* Continue with link-layer output */ return ether_output_frame(ifp, m); } static bool ether_set_pcp(struct mbuf **mp, struct ifnet *ifp, uint8_t pcp) { struct ether_8021q_tag qtag; struct ether_header *eh; eh = mtod(*mp, struct ether_header *); if (ntohs(eh->ether_type) == ETHERTYPE_VLAN || ntohs(eh->ether_type) == ETHERTYPE_QINQ) return (true); qtag.vid = 0; qtag.pcp = pcp; qtag.proto = ETHERTYPE_VLAN; if (ether_8021q_frame(mp, ifp, ifp, &qtag)) return (true); if_inc_counter(ifp, IFCOUNTER_OERRORS, 1); return (false); } /* * Ethernet link layer output routine to send a raw frame to the device. * * This assumes that the 14 byte Ethernet header is present and contiguous * in the first mbuf (if BRIDGE'ing). */ int ether_output_frame(struct ifnet *ifp, struct mbuf *m) { uint8_t pcp; pcp = ifp->if_pcp; if (pcp != IFNET_PCP_NONE && ifp->if_type != IFT_L2VLAN && !ether_set_pcp(&m, ifp, pcp)) return (0); if (PFIL_HOOKED_OUT(V_link_pfil_head)) switch (pfil_run_hooks(V_link_pfil_head, &m, ifp, PFIL_OUT, NULL)) { case PFIL_DROPPED: return (EACCES); case PFIL_CONSUMED: return (0); } #ifdef EXPERIMENTAL #if defined(INET6) && defined(INET) /* draft-ietf-6man-ipv6only-flag */ /* Catch ETHERTYPE_IP, and ETHERTYPE_[REV]ARP if we are v6-only. */ if ((ND_IFINFO(ifp)->flags & ND6_IFF_IPV6_ONLY_MASK) != 0) { struct ether_header *eh; eh = mtod(m, struct ether_header *); switch (ntohs(eh->ether_type)) { case ETHERTYPE_IP: case ETHERTYPE_ARP: case ETHERTYPE_REVARP: m_freem(m); return (EAFNOSUPPORT); /* NOTREACHED */ break; }; } #endif #endif /* * Queue message on interface, update output statistics if * successful, and start output if interface not yet active. */ return ((ifp->if_transmit)(ifp, m)); } /* * Process a received Ethernet packet; the packet is in the * mbuf chain m with the ethernet header at the front. */ static void ether_input_internal(struct ifnet *ifp, struct mbuf *m) { struct ether_header *eh; u_short etype; if ((ifp->if_flags & IFF_UP) == 0) { m_freem(m); return; } #ifdef DIAGNOSTIC if ((ifp->if_drv_flags & IFF_DRV_RUNNING) == 0) { if_printf(ifp, "discard frame at !IFF_DRV_RUNNING\n"); m_freem(m); return; } #endif if (m->m_len < ETHER_HDR_LEN) { /* XXX maybe should pullup? */ if_printf(ifp, "discard frame w/o leading ethernet " "header (len %u pkt len %u)\n", m->m_len, m->m_pkthdr.len); if_inc_counter(ifp, IFCOUNTER_IERRORS, 1); m_freem(m); return; } eh = mtod(m, struct ether_header *); etype = ntohs(eh->ether_type); random_harvest_queue_ether(m, sizeof(*m)); #ifdef EXPERIMENTAL #if defined(INET6) && defined(INET) /* draft-ietf-6man-ipv6only-flag */ /* Catch ETHERTYPE_IP, and ETHERTYPE_[REV]ARP if we are v6-only. */ if ((ND_IFINFO(ifp)->flags & ND6_IFF_IPV6_ONLY_MASK) != 0) { switch (etype) { case ETHERTYPE_IP: case ETHERTYPE_ARP: case ETHERTYPE_REVARP: m_freem(m); return; /* NOTREACHED */ break; }; } #endif #endif CURVNET_SET_QUIET(ifp->if_vnet); if (ETHER_IS_MULTICAST(eh->ether_dhost)) { if (ETHER_IS_BROADCAST(eh->ether_dhost)) m->m_flags |= M_BCAST; else m->m_flags |= M_MCAST; if_inc_counter(ifp, IFCOUNTER_IMCASTS, 1); } #ifdef MAC /* * Tag the mbuf with an appropriate MAC label before any other * consumers can get to it. */ mac_ifnet_create_mbuf(ifp, m); #endif /* * Give bpf a chance at the packet. */ ETHER_BPF_MTAP(ifp, m); /* * If the CRC is still on the packet, trim it off. We do this once * and once only in case we are re-entered. Nothing else on the * Ethernet receive path expects to see the FCS. */ if (m->m_flags & M_HASFCS) { m_adj(m, -ETHER_CRC_LEN); m->m_flags &= ~M_HASFCS; } if (!(ifp->if_capenable & IFCAP_HWSTATS)) if_inc_counter(ifp, IFCOUNTER_IBYTES, m->m_pkthdr.len); /* Allow monitor mode to claim this frame, after stats are updated. */ if (ifp->if_flags & IFF_MONITOR) { m_freem(m); CURVNET_RESTORE(); return; } /* Handle input from a lagg(4) port */ if (ifp->if_type == IFT_IEEE8023ADLAG) { KASSERT(lagg_input_ethernet_p != NULL, ("%s: if_lagg not loaded!", __func__)); m = (*lagg_input_ethernet_p)(ifp, m); if (m != NULL) ifp = m->m_pkthdr.rcvif; else { CURVNET_RESTORE(); return; } } /* * If the hardware did not process an 802.1Q tag, do this now, * to allow 802.1P priority frames to be passed to the main input * path correctly. */ if ((m->m_flags & M_VLANTAG) == 0 && ((etype == ETHERTYPE_VLAN) || (etype == ETHERTYPE_QINQ))) { struct ether_vlan_header *evl; if (m->m_len < sizeof(*evl) && (m = m_pullup(m, sizeof(*evl))) == NULL) { #ifdef DIAGNOSTIC if_printf(ifp, "cannot pullup VLAN header\n"); #endif if_inc_counter(ifp, IFCOUNTER_IERRORS, 1); CURVNET_RESTORE(); return; } evl = mtod(m, struct ether_vlan_header *); m->m_pkthdr.ether_vtag = ntohs(evl->evl_tag); m->m_flags |= M_VLANTAG; bcopy((char *)evl, (char *)evl + ETHER_VLAN_ENCAP_LEN, ETHER_HDR_LEN - ETHER_TYPE_LEN); m_adj(m, ETHER_VLAN_ENCAP_LEN); eh = mtod(m, struct ether_header *); } M_SETFIB(m, ifp->if_fib); /* Allow ng_ether(4) to claim this frame. */ if (ifp->if_l2com != NULL) { KASSERT(ng_ether_input_p != NULL, ("%s: ng_ether_input_p is NULL", __func__)); m->m_flags &= ~M_PROMISC; (*ng_ether_input_p)(ifp, &m); if (m == NULL) { CURVNET_RESTORE(); return; } eh = mtod(m, struct ether_header *); } /* * Allow if_bridge(4) to claim this frame. * The BRIDGE_INPUT() macro will update ifp if the bridge changed it * and the frame should be delivered locally. */ if (ifp->if_bridge != NULL) { m->m_flags &= ~M_PROMISC; BRIDGE_INPUT(ifp, m); if (m == NULL) { CURVNET_RESTORE(); return; } eh = mtod(m, struct ether_header *); } #if defined(INET) || defined(INET6) /* * Clear M_PROMISC on frame so that carp(4) will see it when the * mbuf flows up to Layer 3. * FreeBSD's implementation of carp(4) uses the inprotosw * to dispatch IPPROTO_CARP. carp(4) also allocates its own * Ethernet addresses of the form 00:00:5e:00:01:xx, which * is outside the scope of the M_PROMISC test below. * TODO: Maintain a hash table of ethernet addresses other than * ether_dhost which may be active on this ifp. */ if (ifp->if_carp && (*carp_forus_p)(ifp, eh->ether_dhost)) { m->m_flags &= ~M_PROMISC; } else #endif { /* * If the frame received was not for our MAC address, set the * M_PROMISC flag on the mbuf chain. The frame may need to * be seen by the rest of the Ethernet input path in case of * re-entry (e.g. bridge, vlan, netgraph) but should not be * seen by upper protocol layers. */ if (!ETHER_IS_MULTICAST(eh->ether_dhost) && bcmp(IF_LLADDR(ifp), eh->ether_dhost, ETHER_ADDR_LEN) != 0) m->m_flags |= M_PROMISC; } ether_demux(ifp, m); CURVNET_RESTORE(); } /* * Ethernet input dispatch; by default, direct dispatch here regardless of * global configuration. However, if RSS is enabled, hook up RSS affinity * so that when deferred or hybrid dispatch is enabled, we can redistribute * load based on RSS. * * XXXRW: Would be nice if the ifnet passed up a flag indicating whether or * not it had already done work distribution via multi-queue. Then we could * direct dispatch in the event load balancing was already complete and * handle the case of interfaces with different capabilities better. * * XXXRW: Sort of want an M_DISTRIBUTED flag to avoid multiple distributions * at multiple layers? * * XXXRW: For now, enable all this only if RSS is compiled in, although it * works fine without RSS. Need to characterise the performance overhead * of the detour through the netisr code in the event the result is always * direct dispatch. */ static void ether_nh_input(struct mbuf *m) { M_ASSERTPKTHDR(m); KASSERT(m->m_pkthdr.rcvif != NULL, ("%s: NULL interface pointer", __func__)); ether_input_internal(m->m_pkthdr.rcvif, m); } static struct netisr_handler ether_nh = { .nh_name = "ether", .nh_handler = ether_nh_input, .nh_proto = NETISR_ETHER, #ifdef RSS .nh_policy = NETISR_POLICY_CPU, .nh_dispatch = NETISR_DISPATCH_DIRECT, .nh_m2cpuid = rss_m2cpuid, #else .nh_policy = NETISR_POLICY_SOURCE, .nh_dispatch = NETISR_DISPATCH_DIRECT, #endif }; static void ether_init(__unused void *arg) { netisr_register(ðer_nh); } SYSINIT(ether, SI_SUB_INIT_IF, SI_ORDER_ANY, ether_init, NULL); static void vnet_ether_init(__unused void *arg) { struct pfil_head_args args; args.pa_version = PFIL_VERSION; args.pa_flags = PFIL_IN | PFIL_OUT; args.pa_type = PFIL_TYPE_ETHERNET; args.pa_headname = PFIL_ETHER_NAME; V_link_pfil_head = pfil_head_register(&args); #ifdef VIMAGE netisr_register_vnet(ðer_nh); #endif } VNET_SYSINIT(vnet_ether_init, SI_SUB_PROTO_IF, SI_ORDER_ANY, vnet_ether_init, NULL); #ifdef VIMAGE static void vnet_ether_pfil_destroy(__unused void *arg) { pfil_head_unregister(V_link_pfil_head); } VNET_SYSUNINIT(vnet_ether_pfil_uninit, SI_SUB_PROTO_PFIL, SI_ORDER_ANY, vnet_ether_pfil_destroy, NULL); static void vnet_ether_destroy(__unused void *arg) { netisr_unregister_vnet(ðer_nh); } VNET_SYSUNINIT(vnet_ether_uninit, SI_SUB_PROTO_IF, SI_ORDER_ANY, vnet_ether_destroy, NULL); #endif static void ether_input(struct ifnet *ifp, struct mbuf *m) { struct epoch_tracker et; struct mbuf *mn; bool needs_epoch; needs_epoch = !(ifp->if_flags & IFF_KNOWSEPOCH); /* * The drivers are allowed to pass in a chain of packets linked with * m_nextpkt. We split them up into separate packets here and pass * them up. This allows the drivers to amortize the receive lock. */ CURVNET_SET_QUIET(ifp->if_vnet); if (__predict_false(needs_epoch)) NET_EPOCH_ENTER(et); while (m) { mn = m->m_nextpkt; m->m_nextpkt = NULL; /* * We will rely on rcvif being set properly in the deferred * context, so assert it is correct here. */ MPASS((m->m_pkthdr.csum_flags & CSUM_SND_TAG) == 0); KASSERT(m->m_pkthdr.rcvif == ifp, ("%s: ifnet mismatch m %p " "rcvif %p ifp %p", __func__, m, m->m_pkthdr.rcvif, ifp)); netisr_dispatch(NETISR_ETHER, m); m = mn; } if (__predict_false(needs_epoch)) NET_EPOCH_EXIT(et); CURVNET_RESTORE(); } /* * Upper layer processing for a received Ethernet packet. */ void ether_demux(struct ifnet *ifp, struct mbuf *m) { struct ether_header *eh; int i, isr; u_short ether_type; NET_EPOCH_ASSERT(); KASSERT(ifp != NULL, ("%s: NULL interface pointer", __func__)); /* Do not grab PROMISC frames in case we are re-entered. */ if (PFIL_HOOKED_IN(V_link_pfil_head) && !(m->m_flags & M_PROMISC)) { i = pfil_run_hooks(V_link_pfil_head, &m, ifp, PFIL_IN, NULL); if (i != 0 || m == NULL) return; } eh = mtod(m, struct ether_header *); ether_type = ntohs(eh->ether_type); /* * If this frame has a VLAN tag other than 0, call vlan_input() * if its module is loaded. Otherwise, drop. */ if ((m->m_flags & M_VLANTAG) && EVL_VLANOFTAG(m->m_pkthdr.ether_vtag) != 0) { if (ifp->if_vlantrunk == NULL) { if_inc_counter(ifp, IFCOUNTER_NOPROTO, 1); m_freem(m); return; } KASSERT(vlan_input_p != NULL,("%s: VLAN not loaded!", __func__)); /* Clear before possibly re-entering ether_input(). */ m->m_flags &= ~M_PROMISC; (*vlan_input_p)(ifp, m); return; } /* * Pass promiscuously received frames to the upper layer if the user * requested this by setting IFF_PPROMISC. Otherwise, drop them. */ if ((ifp->if_flags & IFF_PPROMISC) == 0 && (m->m_flags & M_PROMISC)) { m_freem(m); return; } /* * Reset layer specific mbuf flags to avoid confusing upper layers. * Strip off Ethernet header. */ m->m_flags &= ~M_VLANTAG; m_clrprotoflags(m); m_adj(m, ETHER_HDR_LEN); /* * Dispatch frame to upper layer. */ switch (ether_type) { #ifdef INET case ETHERTYPE_IP: isr = NETISR_IP; break; case ETHERTYPE_ARP: if (ifp->if_flags & IFF_NOARP) { /* Discard packet if ARP is disabled on interface */ m_freem(m); return; } isr = NETISR_ARP; break; #endif #ifdef INET6 case ETHERTYPE_IPV6: isr = NETISR_IPV6; break; #endif default: goto discard; } netisr_dispatch(isr, m); return; discard: /* * Packet is to be discarded. If netgraph is present, * hand the packet to it for last chance processing; * otherwise dispose of it. */ if (ifp->if_l2com != NULL) { KASSERT(ng_ether_input_orphan_p != NULL, ("ng_ether_input_orphan_p is NULL")); /* * Put back the ethernet header so netgraph has a * consistent view of inbound packets. */ M_PREPEND(m, ETHER_HDR_LEN, M_NOWAIT); (*ng_ether_input_orphan_p)(ifp, m); return; } m_freem(m); } /* * Convert Ethernet address to printable (loggable) representation. * This routine is for compatibility; it's better to just use * * printf("%6D", , ":"); * * since there's no static buffer involved. */ char * ether_sprintf(const u_char *ap) { static char etherbuf[18]; snprintf(etherbuf, sizeof (etherbuf), "%6D", ap, ":"); return (etherbuf); } /* * Perform common duties while attaching to interface list */ void ether_ifattach(struct ifnet *ifp, const u_int8_t *lla) { int i; struct ifaddr *ifa; struct sockaddr_dl *sdl; ifp->if_addrlen = ETHER_ADDR_LEN; ifp->if_hdrlen = ETHER_HDR_LEN; ifp->if_mtu = ETHERMTU; if_attach(ifp); ifp->if_output = ether_output; ifp->if_input = ether_input; ifp->if_resolvemulti = ether_resolvemulti; ifp->if_requestencap = ether_requestencap; #ifdef VIMAGE ifp->if_reassign = ether_reassign; #endif if (ifp->if_baudrate == 0) ifp->if_baudrate = IF_Mbps(10); /* just a default */ ifp->if_broadcastaddr = etherbroadcastaddr; ifa = ifp->if_addr; KASSERT(ifa != NULL, ("%s: no lladdr!\n", __func__)); sdl = (struct sockaddr_dl *)ifa->ifa_addr; sdl->sdl_type = IFT_ETHER; sdl->sdl_alen = ifp->if_addrlen; bcopy(lla, LLADDR(sdl), ifp->if_addrlen); if (ifp->if_hw_addr != NULL) bcopy(lla, ifp->if_hw_addr, ifp->if_addrlen); bpfattach(ifp, DLT_EN10MB, ETHER_HDR_LEN); if (ng_ether_attach_p != NULL) (*ng_ether_attach_p)(ifp); /* Announce Ethernet MAC address if non-zero. */ for (i = 0; i < ifp->if_addrlen; i++) if (lla[i] != 0) break; if (i != ifp->if_addrlen) if_printf(ifp, "Ethernet address: %6D\n", lla, ":"); uuid_ether_add(LLADDR(sdl)); /* Add necessary bits are setup; announce it now. */ EVENTHANDLER_INVOKE(ether_ifattach_event, ifp); if (IS_DEFAULT_VNET(curvnet)) devctl_notify("ETHERNET", ifp->if_xname, "IFATTACH", NULL); } /* * Perform common duties while detaching an Ethernet interface */ void ether_ifdetach(struct ifnet *ifp) { struct sockaddr_dl *sdl; sdl = (struct sockaddr_dl *)(ifp->if_addr->ifa_addr); uuid_ether_del(LLADDR(sdl)); if (ifp->if_l2com != NULL) { KASSERT(ng_ether_detach_p != NULL, ("ng_ether_detach_p is NULL")); (*ng_ether_detach_p)(ifp); } bpfdetach(ifp); if_detach(ifp); } #ifdef VIMAGE void ether_reassign(struct ifnet *ifp, struct vnet *new_vnet, char *unused __unused) { if (ifp->if_l2com != NULL) { KASSERT(ng_ether_detach_p != NULL, ("ng_ether_detach_p is NULL")); (*ng_ether_detach_p)(ifp); } if (ng_ether_attach_p != NULL) { CURVNET_SET_QUIET(new_vnet); (*ng_ether_attach_p)(ifp); CURVNET_RESTORE(); } } #endif SYSCTL_DECL(_net_link); SYSCTL_NODE(_net_link, IFT_ETHER, ether, CTLFLAG_RW | CTLFLAG_MPSAFE, 0, "Ethernet"); #if 0 /* * This is for reference. We have a table-driven version * of the little-endian crc32 generator, which is faster * than the double-loop. */ uint32_t ether_crc32_le(const uint8_t *buf, size_t len) { size_t i; uint32_t crc; int bit; uint8_t data; crc = 0xffffffff; /* initial value */ for (i = 0; i < len; i++) { for (data = *buf++, bit = 0; bit < 8; bit++, data >>= 1) { carry = (crc ^ data) & 1; crc >>= 1; if (carry) crc = (crc ^ ETHER_CRC_POLY_LE); } } return (crc); } #else uint32_t ether_crc32_le(const uint8_t *buf, size_t len) { static const uint32_t crctab[] = { 0x00000000, 0x1db71064, 0x3b6e20c8, 0x26d930ac, 0x76dc4190, 0x6b6b51f4, 0x4db26158, 0x5005713c, 0xedb88320, 0xf00f9344, 0xd6d6a3e8, 0xcb61b38c, 0x9b64c2b0, 0x86d3d2d4, 0xa00ae278, 0xbdbdf21c }; size_t i; uint32_t crc; crc = 0xffffffff; /* initial value */ for (i = 0; i < len; i++) { crc ^= buf[i]; crc = (crc >> 4) ^ crctab[crc & 0xf]; crc = (crc >> 4) ^ crctab[crc & 0xf]; } return (crc); } #endif uint32_t ether_crc32_be(const uint8_t *buf, size_t len) { size_t i; uint32_t crc, carry; int bit; uint8_t data; crc = 0xffffffff; /* initial value */ for (i = 0; i < len; i++) { for (data = *buf++, bit = 0; bit < 8; bit++, data >>= 1) { carry = ((crc & 0x80000000) ? 1 : 0) ^ (data & 0x01); crc <<= 1; if (carry) crc = (crc ^ ETHER_CRC_POLY_BE) | carry; } } return (crc); } int ether_ioctl(struct ifnet *ifp, u_long command, caddr_t data) { struct ifaddr *ifa = (struct ifaddr *) data; struct ifreq *ifr = (struct ifreq *) data; int error = 0; switch (command) { case SIOCSIFADDR: ifp->if_flags |= IFF_UP; switch (ifa->ifa_addr->sa_family) { #ifdef INET case AF_INET: ifp->if_init(ifp->if_softc); /* before arpwhohas */ arp_ifinit(ifp, ifa); break; #endif default: ifp->if_init(ifp->if_softc); break; } break; case SIOCGIFADDR: bcopy(IF_LLADDR(ifp), &ifr->ifr_addr.sa_data[0], ETHER_ADDR_LEN); break; case SIOCSIFMTU: /* * Set the interface MTU. */ if (ifr->ifr_mtu > ETHERMTU) { error = EINVAL; } else { ifp->if_mtu = ifr->ifr_mtu; } break; case SIOCSLANPCP: error = priv_check(curthread, PRIV_NET_SETLANPCP); if (error != 0) break; if (ifr->ifr_lan_pcp > 7 && ifr->ifr_lan_pcp != IFNET_PCP_NONE) { error = EINVAL; } else { ifp->if_pcp = ifr->ifr_lan_pcp; /* broadcast event about PCP change */ EVENTHANDLER_INVOKE(ifnet_event, ifp, IFNET_EVENT_PCP); } break; case SIOCGLANPCP: ifr->ifr_lan_pcp = ifp->if_pcp; break; default: error = EINVAL; /* XXX netbsd has ENOTTY??? */ break; } return (error); } static int ether_resolvemulti(struct ifnet *ifp, struct sockaddr **llsa, struct sockaddr *sa) { struct sockaddr_dl *sdl; #ifdef INET struct sockaddr_in *sin; #endif #ifdef INET6 struct sockaddr_in6 *sin6; #endif u_char *e_addr; switch(sa->sa_family) { case AF_LINK: /* * No mapping needed. Just check that it's a valid MC address. */ sdl = (struct sockaddr_dl *)sa; e_addr = LLADDR(sdl); if (!ETHER_IS_MULTICAST(e_addr)) return EADDRNOTAVAIL; *llsa = NULL; return 0; #ifdef INET case AF_INET: sin = (struct sockaddr_in *)sa; if (!IN_MULTICAST(ntohl(sin->sin_addr.s_addr))) return EADDRNOTAVAIL; sdl = link_init_sdl(ifp, *llsa, IFT_ETHER); sdl->sdl_alen = ETHER_ADDR_LEN; e_addr = LLADDR(sdl); ETHER_MAP_IP_MULTICAST(&sin->sin_addr, e_addr); *llsa = (struct sockaddr *)sdl; return 0; #endif #ifdef INET6 case AF_INET6: sin6 = (struct sockaddr_in6 *)sa; if (IN6_IS_ADDR_UNSPECIFIED(&sin6->sin6_addr)) { /* * An IP6 address of 0 means listen to all * of the Ethernet multicast address used for IP6. * (This is used for multicast routers.) */ ifp->if_flags |= IFF_ALLMULTI; *llsa = NULL; return 0; } if (!IN6_IS_ADDR_MULTICAST(&sin6->sin6_addr)) return EADDRNOTAVAIL; sdl = link_init_sdl(ifp, *llsa, IFT_ETHER); sdl->sdl_alen = ETHER_ADDR_LEN; e_addr = LLADDR(sdl); ETHER_MAP_IPV6_MULTICAST(&sin6->sin6_addr, e_addr); *llsa = (struct sockaddr *)sdl; return 0; #endif default: /* * Well, the text isn't quite right, but it's the name * that counts... */ return EAFNOSUPPORT; } } static moduledata_t ether_mod = { .name = "ether", }; void ether_vlan_mtap(struct bpf_if *bp, struct mbuf *m, void *data, u_int dlen) { struct ether_vlan_header vlan; struct mbuf mv, mb; KASSERT((m->m_flags & M_VLANTAG) != 0, ("%s: vlan information not present", __func__)); KASSERT(m->m_len >= sizeof(struct ether_header), ("%s: mbuf not large enough for header", __func__)); bcopy(mtod(m, char *), &vlan, sizeof(struct ether_header)); vlan.evl_proto = vlan.evl_encap_proto; vlan.evl_encap_proto = htons(ETHERTYPE_VLAN); vlan.evl_tag = htons(m->m_pkthdr.ether_vtag); m->m_len -= sizeof(struct ether_header); m->m_data += sizeof(struct ether_header); /* * If a data link has been supplied by the caller, then we will need to * re-create a stack allocated mbuf chain with the following structure: * * (1) mbuf #1 will contain the supplied data link * (2) mbuf #2 will contain the vlan header * (3) mbuf #3 will contain the original mbuf's packet data * * Otherwise, submit the packet and vlan header via bpf_mtap2(). */ if (data != NULL) { mv.m_next = m; mv.m_data = (caddr_t)&vlan; mv.m_len = sizeof(vlan); mb.m_next = &mv; mb.m_data = data; mb.m_len = dlen; bpf_mtap(bp, &mb); } else bpf_mtap2(bp, &vlan, sizeof(vlan), m); m->m_len += sizeof(struct ether_header); m->m_data -= sizeof(struct ether_header); } struct mbuf * ether_vlanencap_proto(struct mbuf *m, uint16_t tag, uint16_t proto) { struct ether_vlan_header *evl; M_PREPEND(m, ETHER_VLAN_ENCAP_LEN, M_NOWAIT); if (m == NULL) return (NULL); /* M_PREPEND takes care of m_len, m_pkthdr.len for us */ if (m->m_len < sizeof(*evl)) { m = m_pullup(m, sizeof(*evl)); if (m == NULL) return (NULL); } /* * Transform the Ethernet header into an Ethernet header * with 802.1Q encapsulation. */ evl = mtod(m, struct ether_vlan_header *); bcopy((char *)evl + ETHER_VLAN_ENCAP_LEN, (char *)evl, ETHER_HDR_LEN - ETHER_TYPE_LEN); evl->evl_encap_proto = htons(proto); evl->evl_tag = htons(tag); return (m); } static SYSCTL_NODE(_net_link, IFT_L2VLAN, vlan, CTLFLAG_RW | CTLFLAG_MPSAFE, 0, "IEEE 802.1Q VLAN"); static SYSCTL_NODE(_net_link_vlan, PF_LINK, link, CTLFLAG_RW | CTLFLAG_MPSAFE, 0, "for consistency"); VNET_DEFINE_STATIC(int, soft_pad); #define V_soft_pad VNET(soft_pad) SYSCTL_INT(_net_link_vlan, OID_AUTO, soft_pad, CTLFLAG_RW | CTLFLAG_VNET, &VNET_NAME(soft_pad), 0, "pad short frames before tagging"); /* * For now, make preserving PCP via an mbuf tag optional, as it increases * per-packet memory allocations and frees. In the future, it would be * preferable to reuse ether_vtag for this, or similar. */ int vlan_mtag_pcp = 0; SYSCTL_INT(_net_link_vlan, OID_AUTO, mtag_pcp, CTLFLAG_RW, &vlan_mtag_pcp, 0, "Retain VLAN PCP information as packets are passed up the stack"); bool ether_8021q_frame(struct mbuf **mp, struct ifnet *ife, struct ifnet *p, struct ether_8021q_tag *qtag) { struct m_tag *mtag; int n; uint16_t tag; static const char pad[8]; /* just zeros */ /* * Pad the frame to the minimum size allowed if told to. * This option is in accord with IEEE Std 802.1Q, 2003 Ed., * paragraph C.4.4.3.b. It can help to work around buggy * bridges that violate paragraph C.4.4.3.a from the same * document, i.e., fail to pad short frames after untagging. * E.g., a tagged frame 66 bytes long (incl. FCS) is OK, but * untagging it will produce a 62-byte frame, which is a runt * and requires padding. There are VLAN-enabled network * devices that just discard such runts instead or mishandle * them somehow. */ if (V_soft_pad && p->if_type == IFT_ETHER) { for (n = ETHERMIN + ETHER_HDR_LEN - (*mp)->m_pkthdr.len; n > 0; n -= sizeof(pad)) { if (!m_append(*mp, min(n, sizeof(pad)), pad)) break; } if (n > 0) { m_freem(*mp); *mp = NULL; if_printf(ife, "cannot pad short frame"); return (false); } } /* * If PCP is set in mbuf, use it */ if ((*mp)->m_flags & M_VLANTAG) { qtag->pcp = EVL_PRIOFTAG((*mp)->m_pkthdr.ether_vtag); } /* * If underlying interface can do VLAN tag insertion itself, * just pass the packet along. However, we need some way to * tell the interface where the packet came from so that it * knows how to find the VLAN tag to use, so we attach a * packet tag that holds it. */ if (vlan_mtag_pcp && (mtag = m_tag_locate(*mp, MTAG_8021Q, MTAG_8021Q_PCP_OUT, NULL)) != NULL) tag = EVL_MAKETAG(qtag->vid, *(uint8_t *)(mtag + 1), 0); else tag = EVL_MAKETAG(qtag->vid, qtag->pcp, 0); if ((p->if_capenable & IFCAP_VLAN_HWTAGGING) && (qtag->proto == ETHERTYPE_VLAN)) { (*mp)->m_pkthdr.ether_vtag = tag; (*mp)->m_flags |= M_VLANTAG; } else { *mp = ether_vlanencap_proto(*mp, tag, qtag->proto); if (*mp == NULL) { if_printf(ife, "unable to prepend 802.1Q header"); return (false); } } return (true); } /* * Allocate an address from the FreeBSD Foundation OUI. This uses a * cryptographic hash function on the containing jail's name, UUID and the * interface name to attempt to provide a unique but stable address. * Pseudo-interfaces which require a MAC address should use this function to * allocate non-locally-administered addresses. */ void ether_gen_addr(struct ifnet *ifp, struct ether_addr *hwaddr) { SHA1_CTX ctx; char *buf; char uuid[HOSTUUIDLEN + 1]; uint64_t addr; int i, sz; char digest[SHA1_RESULTLEN]; char jailname[MAXHOSTNAMELEN]; getcredhostuuid(curthread->td_ucred, uuid, sizeof(uuid)); if (strncmp(uuid, DEFAULT_HOSTUUID, sizeof(uuid)) == 0) { /* Fall back to a random mac address. */ goto rando; } /* If each (vnet) jail would also have a unique hostuuid this would not * be necessary. */ getjailname(curthread->td_ucred, jailname, sizeof(jailname)); sz = asprintf(&buf, M_TEMP, "%s-%s-%s", uuid, if_name(ifp), jailname); if (sz < 0) { /* Fall back to a random mac address. */ goto rando; } SHA1Init(&ctx); SHA1Update(&ctx, buf, sz); SHA1Final(digest, &ctx); free(buf, M_TEMP); addr = ((digest[0] << 16) | (digest[1] << 8) | digest[2]) & OUI_FREEBSD_GENERATED_MASK; addr = OUI_FREEBSD(addr); for (i = 0; i < ETHER_ADDR_LEN; ++i) { hwaddr->octet[i] = addr >> ((ETHER_ADDR_LEN - i - 1) * 8) & 0xFF; } return; rando: arc4rand(hwaddr, sizeof(*hwaddr), 0); /* Unicast */ hwaddr->octet[0] &= 0xFE; /* Locally administered. */ hwaddr->octet[0] |= 0x02; } DECLARE_MODULE(ether, ether_mod, SI_SUB_INIT_IF, SI_ORDER_ANY); MODULE_VERSION(ether, 1);