Index: head/sys/net/if_ethersubr.c =================================================================== --- head/sys/net/if_ethersubr.c (revision 293034) +++ head/sys/net/if_ethersubr.c (revision 293035) @@ -1,1196 +1,1200 @@ /*- * 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. * 4. 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 #if defined(INET) || defined(INET6) #include #include #include #include #include #endif #ifdef INET6 #include #endif #include #ifdef CTASSERT CTASSERT(sizeof (struct ether_header) == ETHER_ADDR_LEN * 2 + 2); CTASSERT(sizeof (struct ether_addr) == ETHER_ADDR_LEN); #endif VNET_DEFINE(struct pfil_head, link_pfil_hook); /* 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 */ struct mbuf *(*bridge_input_p)(struct ifnet *, struct mbuf *); int (*bridge_output_p)(struct ifnet *, struct mbuf *, struct sockaddr *, struct rtentry *); void (*bridge_dn_p)(struct mbuf *, struct ifnet *); /* if_lagg(4) support */ struct mbuf *(*lagg_input_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 *); #ifdef VIMAGE static void ether_reassign(struct ifnet *, struct vnet *, char *); #endif static int ether_requestencap(struct ifnet *, struct if_encap_req *); #define ETHER_IS_BROADCAST(addr) \ (bcmp(etherbroadcastaddr, (addr), ETHER_ADDR_LEN) == 0) #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 ether_header *eh; struct rtentry *rt; uint32_t lleflags = 0; int error = 0; #if defined(INET) || defined(INET6) uint16_t etype; #endif 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); 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); 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) { rt = (ro != NULL) ? ro->ro_rt : NULL; if (rt != NULL && (rt->rt_flags & RTF_GATEWAY) != 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; int loop_copy = 1; int hlen; /* link layer header length */ uint32_t pflags; phdr = NULL; pflags = 0; if (ro != NULL) { phdr = ro->ro_prepend; hlen = ro->ro_plen; pflags = ro->ro_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); 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; /* * 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); } /* * 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) { int i; if (PFIL_HOOKED(&V_link_pfil_hook)) { i = pfil_run_hooks(&V_link_pfil_hook, &m, ifp, PFIL_OUT, NULL); if (i != 0) return (EACCES); if (m == NULL) return (0); } /* * Queue message on interface, update output statistics if * successful, and start output if interface not yet active. */ return ((ifp->if_transmit)(ifp, m)); } #if defined(INET) || defined(INET6) #endif /* * 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(m, sizeof(*m), 2, RANDOM_NET_ETHER); 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_p != NULL, ("%s: if_lagg not loaded!", __func__)); m = (*lagg_input_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. * TODO: Deal with Q-in-Q frames, but not arbitrary nesting levels. */ if ((m->m_flags & M_VLANTAG) == 0 && etype == ETHERTYPE_VLAN) { 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) { int i; /* Initialize packet filter hooks. */ V_link_pfil_hook.ph_type = PFIL_TYPE_AF; V_link_pfil_hook.ph_af = AF_LINK; if ((i = pfil_head_register(&V_link_pfil_hook)) != 0) printf("%s: WARNING: unable to register pfil link hook, " "error %d\n", __func__, i); } VNET_SYSINIT(vnet_ether_init, SI_SUB_PROTO_IF, SI_ORDER_ANY, vnet_ether_init, NULL); static void vnet_ether_destroy(__unused void *arg) { int i; if ((i = pfil_head_unregister(&V_link_pfil_hook)) != 0) printf("%s: WARNING: unable to unregister pfil link hook, " "error %d\n", __func__, i); } VNET_SYSUNINIT(vnet_ether_uninit, SI_SUB_PROTO_IF, SI_ORDER_ANY, vnet_ether_destroy, NULL); static void ether_input(struct ifnet *ifp, struct mbuf *m) { struct mbuf *mn; /* * 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. */ 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. */ KASSERT(m->m_pkthdr.rcvif == ifp, ("%s: ifnet mismatch", __func__)); netisr_dispatch(NETISR_ETHER, m); m = mn; } } /* * 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; KASSERT(ifp != NULL, ("%s: NULL interface pointer", __func__)); /* Do not grab PROMISC frames in case we are re-entered. */ if (PFIL_HOOKED(&V_link_pfil_hook) && !(m->m_flags & M_PROMISC)) { i = pfil_run_hooks(&V_link_pfil_hook, &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; if_attach(ifp); ifp->if_mtu = ETHERMTU; 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); 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)); } /* * 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, 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: { struct sockaddr *sa; sa = (struct sockaddr *) & ifr->ifr_data; bcopy(IF_LLADDR(ifp), (caddr_t) sa->sa_data, 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; 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 = 0; 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 = 0; 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(struct mbuf *m, uint16_t tag) { 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(ETHERTYPE_VLAN); evl->evl_tag = htons(tag); return (m); } DECLARE_MODULE(ether, ether_mod, SI_SUB_INIT_IF, SI_ORDER_ANY); MODULE_VERSION(ether, 1); Index: head/sys/netinet/if_ether.c =================================================================== --- head/sys/netinet/if_ether.c (revision 293034) +++ head/sys/netinet/if_ether.c (revision 293035) @@ -1,1341 +1,1338 @@ /*- * Copyright (c) 1982, 1986, 1988, 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. * 4. 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_ether.c 8.1 (Berkeley) 6/10/93 */ /* * Ethernet address resolution protocol. * TODO: * add "inuse/lock" bit (or ref. count) along with valid bit */ #include __FBSDID("$FreeBSD$"); #include "opt_inet.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 #ifdef INET #include #endif #include #define SIN(s) ((const struct sockaddr_in *)(s)) static struct timeval arp_lastlog; static int arp_curpps; static int arp_maxpps = 1; /* Simple ARP state machine */ enum arp_llinfo_state { ARP_LLINFO_INCOMPLETE = 0, /* No LLE data */ ARP_LLINFO_REACHABLE, /* LLE is valid */ ARP_LLINFO_VERIFY, /* LLE is valid, need refresh */ ARP_LLINFO_DELETED, /* LLE is deleted */ }; SYSCTL_DECL(_net_link_ether); static SYSCTL_NODE(_net_link_ether, PF_INET, inet, CTLFLAG_RW, 0, ""); static SYSCTL_NODE(_net_link_ether, PF_ARP, arp, CTLFLAG_RW, 0, ""); /* timer values */ static VNET_DEFINE(int, arpt_keep) = (20*60); /* once resolved, good for 20 * minutes */ static VNET_DEFINE(int, arp_maxtries) = 5; static VNET_DEFINE(int, arp_proxyall) = 0; static VNET_DEFINE(int, arpt_down) = 20; /* keep incomplete entries for * 20 seconds */ static VNET_DEFINE(int, arpt_rexmit) = 1; /* retransmit arp entries, sec*/ VNET_PCPUSTAT_DEFINE(struct arpstat, arpstat); /* ARP statistics, see if_arp.h */ VNET_PCPUSTAT_SYSINIT(arpstat); #ifdef VIMAGE VNET_PCPUSTAT_SYSUNINIT(arpstat); #endif /* VIMAGE */ static VNET_DEFINE(int, arp_maxhold) = 1; #define V_arpt_keep VNET(arpt_keep) #define V_arpt_down VNET(arpt_down) #define V_arpt_rexmit VNET(arpt_rexmit) #define V_arp_maxtries VNET(arp_maxtries) #define V_arp_proxyall VNET(arp_proxyall) #define V_arp_maxhold VNET(arp_maxhold) SYSCTL_INT(_net_link_ether_inet, OID_AUTO, max_age, CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(arpt_keep), 0, "ARP entry lifetime in seconds"); SYSCTL_INT(_net_link_ether_inet, OID_AUTO, maxtries, CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(arp_maxtries), 0, "ARP resolution attempts before returning error"); SYSCTL_INT(_net_link_ether_inet, OID_AUTO, proxyall, CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(arp_proxyall), 0, "Enable proxy ARP for all suitable requests"); SYSCTL_INT(_net_link_ether_inet, OID_AUTO, wait, CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(arpt_down), 0, "Incomplete ARP entry lifetime in seconds"); SYSCTL_VNET_PCPUSTAT(_net_link_ether_arp, OID_AUTO, stats, struct arpstat, arpstat, "ARP statistics (struct arpstat, net/if_arp.h)"); SYSCTL_INT(_net_link_ether_inet, OID_AUTO, maxhold, CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(arp_maxhold), 0, "Number of packets to hold per ARP entry"); SYSCTL_INT(_net_link_ether_inet, OID_AUTO, max_log_per_second, CTLFLAG_RW, &arp_maxpps, 0, "Maximum number of remotely triggered ARP messages that can be " "logged per second"); #define ARP_LOG(pri, ...) do { \ if (ppsratecheck(&arp_lastlog, &arp_curpps, arp_maxpps)) \ log((pri), "arp: " __VA_ARGS__); \ } while (0) static void arp_init(void); static void arpintr(struct mbuf *); static void arptimer(void *); #ifdef INET static void in_arpinput(struct mbuf *); #endif static void arp_check_update_lle(struct arphdr *ah, struct in_addr isaddr, struct ifnet *ifp, int bridged, struct llentry *la); static void arp_mark_lle_reachable(struct llentry *la); static void arp_iflladdr(void *arg __unused, struct ifnet *ifp); static eventhandler_tag iflladdr_tag; static const struct netisr_handler arp_nh = { .nh_name = "arp", .nh_handler = arpintr, .nh_proto = NETISR_ARP, .nh_policy = NETISR_POLICY_SOURCE, }; /* * Timeout routine. Age arp_tab entries periodically. */ static void arptimer(void *arg) { struct llentry *lle = (struct llentry *)arg; struct ifnet *ifp; int r_skip_req; if (lle->la_flags & LLE_STATIC) { return; } LLE_WLOCK(lle); if (callout_pending(&lle->lle_timer)) { /* * Here we are a bit odd here in the treatment of * active/pending. If the pending bit is set, it got * rescheduled before I ran. The active * bit we ignore, since if it was stopped * in ll_tablefree() and was currently running * it would have return 0 so the code would * not have deleted it since the callout could * not be stopped so we want to go through * with the delete here now. If the callout * was restarted, the pending bit will be back on and * we just want to bail since the callout_reset would * return 1 and our reference would have been removed * by arpresolve() below. */ LLE_WUNLOCK(lle); return; } ifp = lle->lle_tbl->llt_ifp; CURVNET_SET(ifp->if_vnet); switch (lle->ln_state) { case ARP_LLINFO_REACHABLE: /* * Expiration time is approaching. * Let's try to refresh entry if it is still * in use. * * Set r_skip_req to get feedback from * fast path. Change state and re-schedule * ourselves. */ LLE_REQ_LOCK(lle); lle->r_skip_req = 1; LLE_REQ_UNLOCK(lle); lle->ln_state = ARP_LLINFO_VERIFY; callout_schedule(&lle->lle_timer, hz * V_arpt_rexmit); LLE_WUNLOCK(lle); CURVNET_RESTORE(); return; case ARP_LLINFO_VERIFY: LLE_REQ_LOCK(lle); r_skip_req = lle->r_skip_req; LLE_REQ_UNLOCK(lle); if (r_skip_req == 0 && lle->la_preempt > 0) { /* Entry was used, issue refresh request */ struct in_addr dst; dst = lle->r_l3addr.addr4; lle->la_preempt--; callout_schedule(&lle->lle_timer, hz * V_arpt_rexmit); LLE_WUNLOCK(lle); arprequest(ifp, NULL, &dst, NULL); CURVNET_RESTORE(); return; } /* Nothing happened. Reschedule if not too late */ if (lle->la_expire > time_uptime) { callout_schedule(&lle->lle_timer, hz * V_arpt_rexmit); LLE_WUNLOCK(lle); CURVNET_RESTORE(); return; } break; case ARP_LLINFO_INCOMPLETE: case ARP_LLINFO_DELETED: break; } if ((lle->la_flags & LLE_DELETED) == 0) { int evt; if (lle->la_flags & LLE_VALID) evt = LLENTRY_EXPIRED; else evt = LLENTRY_TIMEDOUT; EVENTHANDLER_INVOKE(lle_event, lle, evt); } callout_stop(&lle->lle_timer); /* XXX: LOR avoidance. We still have ref on lle. */ LLE_WUNLOCK(lle); IF_AFDATA_LOCK(ifp); LLE_WLOCK(lle); /* Guard against race with other llentry_free(). */ if (lle->la_flags & LLE_LINKED) { LLE_REMREF(lle); lltable_unlink_entry(lle->lle_tbl, lle); } IF_AFDATA_UNLOCK(ifp); size_t pkts_dropped = llentry_free(lle); ARPSTAT_ADD(dropped, pkts_dropped); ARPSTAT_INC(timeouts); CURVNET_RESTORE(); } /* * Stores link-layer header for @ifp in format suitable for if_output() * into buffer @buf. Resulting header length is stored in @bufsize. * * Returns 0 on success. */ static int arp_fillheader(struct ifnet *ifp, struct arphdr *ah, int bcast, u_char *buf, size_t *bufsize) { struct if_encap_req ereq; int error; bzero(buf, *bufsize); bzero(&ereq, sizeof(ereq)); ereq.buf = buf; ereq.bufsize = *bufsize; ereq.rtype = IFENCAP_LL; ereq.family = AF_ARP; ereq.lladdr = ar_tha(ah); ereq.hdata = (u_char *)ah; if (bcast) ereq.flags = IFENCAP_FLAG_BROADCAST; error = ifp->if_requestencap(ifp, &ereq); if (error == 0) *bufsize = ereq.bufsize; return (error); } /* * Broadcast an ARP request. Caller specifies: * - arp header source ip address * - arp header target ip address * - arp header source ethernet address */ void arprequest(struct ifnet *ifp, const struct in_addr *sip, const struct in_addr *tip, u_char *enaddr) { struct mbuf *m; struct arphdr *ah; struct sockaddr sa; u_char *carpaddr = NULL; uint8_t linkhdr[LLE_MAX_LINKHDR]; size_t linkhdrsize; struct route ro; int error; if (sip == NULL) { /* * The caller did not supply a source address, try to find * a compatible one among those assigned to this interface. */ struct ifaddr *ifa; IF_ADDR_RLOCK(ifp); TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) { if (ifa->ifa_addr->sa_family != AF_INET) continue; if (ifa->ifa_carp) { if ((*carp_iamatch_p)(ifa, &carpaddr) == 0) continue; sip = &IA_SIN(ifa)->sin_addr; } else { carpaddr = NULL; sip = &IA_SIN(ifa)->sin_addr; } if (0 == ((sip->s_addr ^ tip->s_addr) & IA_MASKSIN(ifa)->sin_addr.s_addr)) break; /* found it. */ } IF_ADDR_RUNLOCK(ifp); if (sip == NULL) { printf("%s: cannot find matching address\n", __func__); return; } } if (enaddr == NULL) enaddr = carpaddr ? carpaddr : (u_char *)IF_LLADDR(ifp); if ((m = m_gethdr(M_NOWAIT, MT_DATA)) == NULL) return; m->m_len = sizeof(*ah) + 2 * sizeof(struct in_addr) + 2 * ifp->if_addrlen; m->m_pkthdr.len = m->m_len; M_ALIGN(m, m->m_len); ah = mtod(m, struct arphdr *); bzero((caddr_t)ah, m->m_len); #ifdef MAC mac_netinet_arp_send(ifp, m); #endif ah->ar_pro = htons(ETHERTYPE_IP); ah->ar_hln = ifp->if_addrlen; /* hardware address length */ ah->ar_pln = sizeof(struct in_addr); /* protocol address length */ ah->ar_op = htons(ARPOP_REQUEST); bcopy(enaddr, ar_sha(ah), ah->ar_hln); bcopy(sip, ar_spa(ah), ah->ar_pln); bcopy(tip, ar_tpa(ah), ah->ar_pln); sa.sa_family = AF_ARP; sa.sa_len = 2; /* Calculate link header for sending frame */ bzero(&ro, sizeof(ro)); linkhdrsize = sizeof(linkhdr); error = arp_fillheader(ifp, ah, 1, linkhdr, &linkhdrsize); if (error != 0 && error != EAFNOSUPPORT) { ARP_LOG(LOG_ERR, "Failed to calculate ARP header on %s: %d\n", if_name(ifp), error); return; } ro.ro_prepend = linkhdr; ro.ro_plen = linkhdrsize; ro.ro_flags = 0; m->m_flags |= M_BCAST; m_clrprotoflags(m); /* Avoid confusing lower layers. */ (*ifp->if_output)(ifp, m, &sa, &ro); ARPSTAT_INC(txrequests); } /* * Resolve an IP address into an ethernet address - heavy version. * Used internally by arpresolve(). * We have already checked than we can't use existing lle without * modification so we have to acquire LLE_EXCLUSIVE lle lock. * * On success, desten and flags are filled in and the function returns 0; * If the packet must be held pending resolution, we return EWOULDBLOCK * On other errors, we return the corresponding error code. * Note that m_freem() handles NULL. */ static int arpresolve_full(struct ifnet *ifp, int is_gw, int flags, struct mbuf *m, const struct sockaddr *dst, u_char *desten, uint32_t *pflags) { struct llentry *la = NULL, *la_tmp; struct mbuf *curr = NULL; struct mbuf *next = NULL; int error, renew; char *lladdr; int ll_len; if (pflags != NULL) *pflags = 0; if ((flags & LLE_CREATE) == 0) { IF_AFDATA_RLOCK(ifp); la = lla_lookup(LLTABLE(ifp), LLE_EXCLUSIVE, dst); IF_AFDATA_RUNLOCK(ifp); } if (la == NULL && (ifp->if_flags & (IFF_NOARP | IFF_STATICARP)) == 0) { la = lltable_alloc_entry(LLTABLE(ifp), 0, dst); if (la == NULL) { log(LOG_DEBUG, "arpresolve: can't allocate llinfo for %s on %s\n", inet_ntoa(SIN(dst)->sin_addr), if_name(ifp)); m_freem(m); return (EINVAL); } IF_AFDATA_WLOCK(ifp); LLE_WLOCK(la); la_tmp = lla_lookup(LLTABLE(ifp), LLE_EXCLUSIVE, dst); /* Prefer ANY existing lle over newly-created one */ if (la_tmp == NULL) lltable_link_entry(LLTABLE(ifp), la); IF_AFDATA_WUNLOCK(ifp); if (la_tmp != NULL) { lltable_free_entry(LLTABLE(ifp), la); la = la_tmp; } } if (la == NULL) { m_freem(m); return (EINVAL); } if ((la->la_flags & LLE_VALID) && ((la->la_flags & LLE_STATIC) || la->la_expire > time_uptime)) { if (flags & LLE_ADDRONLY) { lladdr = la->ll_addr; ll_len = ifp->if_addrlen; } else { lladdr = la->r_linkdata; ll_len = la->r_hdrlen; } bcopy(lladdr, desten, ll_len); /* Check if we have feedback request from arptimer() */ if (la->r_skip_req != 0) { LLE_REQ_LOCK(la); la->r_skip_req = 0; /* Notify that entry was used */ LLE_REQ_UNLOCK(la); } if (pflags != NULL) *pflags = la->la_flags & (LLE_VALID|LLE_IFADDR); LLE_WUNLOCK(la); return (0); } renew = (la->la_asked == 0 || la->la_expire != time_uptime); /* * There is an arptab entry, but no ethernet address * response yet. Add the mbuf to the list, dropping * the oldest packet if we have exceeded the system * setting. */ if (m != NULL) { if (la->la_numheld >= V_arp_maxhold) { if (la->la_hold != NULL) { next = la->la_hold->m_nextpkt; m_freem(la->la_hold); la->la_hold = next; la->la_numheld--; ARPSTAT_INC(dropped); } } if (la->la_hold != NULL) { curr = la->la_hold; while (curr->m_nextpkt != NULL) curr = curr->m_nextpkt; curr->m_nextpkt = m; } else la->la_hold = m; la->la_numheld++; } /* * Return EWOULDBLOCK if we have tried less than arp_maxtries. It * will be masked by ether_output(). Return EHOSTDOWN/EHOSTUNREACH * if we have already sent arp_maxtries ARP requests. Retransmit the * ARP request, but not faster than one request per second. */ if (la->la_asked < V_arp_maxtries) error = EWOULDBLOCK; /* First request. */ else error = is_gw != 0 ? EHOSTUNREACH : EHOSTDOWN; if (renew) { int canceled; LLE_ADDREF(la); la->la_expire = time_uptime; canceled = callout_reset(&la->lle_timer, hz * V_arpt_down, arptimer, la); if (canceled) LLE_REMREF(la); la->la_asked++; LLE_WUNLOCK(la); arprequest(ifp, NULL, &SIN(dst)->sin_addr, NULL); return (error); } LLE_WUNLOCK(la); return (error); } /* * Resolve an IP address into an ethernet address. */ int arpresolve_addr(struct ifnet *ifp, int flags, const struct sockaddr *dst, char *desten, uint32_t *pflags) { int error; flags |= LLE_ADDRONLY; error = arpresolve_full(ifp, 0, flags, NULL, dst, desten, pflags); return (error); } /* * Lookups link header based on an IP address. * On input: * ifp is the interface we use * is_gw != 0 if @dst represents gateway to some destination * m is the mbuf. May be NULL if we don't have a packet. * dst is the next hop, * desten is the storage to put LL header. * flags returns subset of lle flags: LLE_VALID | LLE_IFADDR * * On success, full/partial link header and flags are filled in and * the function returns 0. * If the packet must be held pending resolution, we return EWOULDBLOCK * On other errors, we return the corresponding error code. * Note that m_freem() handles NULL. */ int arpresolve(struct ifnet *ifp, int is_gw, struct mbuf *m, const struct sockaddr *dst, u_char *desten, uint32_t *pflags) { struct llentry *la = 0; if (pflags != NULL) *pflags = 0; if (m != NULL) { if (m->m_flags & M_BCAST) { /* broadcast */ (void)memcpy(desten, ifp->if_broadcastaddr, ifp->if_addrlen); return (0); } if (m->m_flags & M_MCAST) { /* multicast */ ETHER_MAP_IP_MULTICAST(&SIN(dst)->sin_addr, desten); return (0); } } IF_AFDATA_RLOCK(ifp); la = lla_lookup(LLTABLE(ifp), LLE_UNLOCKED, dst); if (la != NULL && (la->r_flags & RLLE_VALID) != 0) { /* Entry found, let's copy lle info */ bcopy(la->r_linkdata, desten, la->r_hdrlen); if (pflags != NULL) *pflags = LLE_VALID | (la->r_flags & RLLE_IFADDR); /* Check if we have feedback request from arptimer() */ if (la->r_skip_req != 0) { LLE_REQ_LOCK(la); la->r_skip_req = 0; /* Notify that entry was used */ LLE_REQ_UNLOCK(la); } IF_AFDATA_RUNLOCK(ifp); return (0); } IF_AFDATA_RUNLOCK(ifp); return (arpresolve_full(ifp, is_gw, la == NULL ? LLE_CREATE : 0, m, dst, desten, pflags)); } /* * Common length and type checks are done here, * then the protocol-specific routine is called. */ static void arpintr(struct mbuf *m) { struct arphdr *ar; struct ifnet *ifp; char *layer; int hlen; ifp = m->m_pkthdr.rcvif; if (m->m_len < sizeof(struct arphdr) && ((m = m_pullup(m, sizeof(struct arphdr))) == NULL)) { ARP_LOG(LOG_NOTICE, "packet with short header received on %s\n", if_name(ifp)); return; } ar = mtod(m, struct arphdr *); /* Check if length is sufficient */ if (m->m_len < arphdr_len(ar)) { m = m_pullup(m, arphdr_len(ar)); if (m == NULL) { ARP_LOG(LOG_NOTICE, "short packet received on %s\n", if_name(ifp)); return; } ar = mtod(m, struct arphdr *); } hlen = 0; layer = ""; switch (ntohs(ar->ar_hrd)) { case ARPHRD_ETHER: hlen = ETHER_ADDR_LEN; /* RFC 826 */ layer = "ethernet"; break; case ARPHRD_IEEE802: hlen = 6; /* RFC 1390, FDDI_ADDR_LEN */ layer = "fddi"; break; case ARPHRD_ARCNET: hlen = 1; /* RFC 1201, ARC_ADDR_LEN */ layer = "arcnet"; break; case ARPHRD_INFINIBAND: hlen = 20; /* RFC 4391, INFINIBAND_ALEN */ layer = "infiniband"; break; case ARPHRD_IEEE1394: hlen = 0; /* SHALL be 16 */ /* RFC 2734 */ layer = "firewire"; /* * Restrict too long hardware addresses. * Currently we are capable of handling 20-byte * addresses ( sizeof(lle->ll_addr) ) */ if (ar->ar_hln >= 20) hlen = 16; break; default: ARP_LOG(LOG_NOTICE, "packet with unknown hardware format 0x%02d received on " "%s\n", ntohs(ar->ar_hrd), if_name(ifp)); m_freem(m); return; } if (hlen != 0 && hlen != ar->ar_hln) { ARP_LOG(LOG_NOTICE, "packet with invalid %s address length %d received on %s\n", layer, ar->ar_hln, if_name(ifp)); m_freem(m); return; } ARPSTAT_INC(received); switch (ntohs(ar->ar_pro)) { #ifdef INET case ETHERTYPE_IP: in_arpinput(m); return; #endif } m_freem(m); } #ifdef INET /* * ARP for Internet protocols on 10 Mb/s Ethernet. * Algorithm is that given in RFC 826. * In addition, a sanity check is performed on the sender * protocol address, to catch impersonators. * We no longer handle negotiations for use of trailer protocol: * Formerly, ARP replied for protocol type ETHERTYPE_TRAIL sent * along with IP replies if we wanted trailers sent to us, * and also sent them in response to IP replies. * This allowed either end to announce the desire to receive * trailer packets. * We no longer reply to requests for ETHERTYPE_TRAIL protocol either, * but formerly didn't normally send requests. */ static int log_arp_wrong_iface = 1; static int log_arp_movements = 1; static int log_arp_permanent_modify = 1; static int allow_multicast = 0; SYSCTL_INT(_net_link_ether_inet, OID_AUTO, log_arp_wrong_iface, CTLFLAG_RW, &log_arp_wrong_iface, 0, "log arp packets arriving on the wrong interface"); SYSCTL_INT(_net_link_ether_inet, OID_AUTO, log_arp_movements, CTLFLAG_RW, &log_arp_movements, 0, "log arp replies from MACs different than the one in the cache"); SYSCTL_INT(_net_link_ether_inet, OID_AUTO, log_arp_permanent_modify, CTLFLAG_RW, &log_arp_permanent_modify, 0, "log arp replies from MACs different than the one in the permanent arp entry"); SYSCTL_INT(_net_link_ether_inet, OID_AUTO, allow_multicast, CTLFLAG_RW, &allow_multicast, 0, "accept multicast addresses"); static void in_arpinput(struct mbuf *m) { struct rm_priotracker in_ifa_tracker; struct arphdr *ah; struct ifnet *ifp = m->m_pkthdr.rcvif; struct llentry *la = NULL, *la_tmp; struct ifaddr *ifa; struct in_ifaddr *ia; struct sockaddr sa; struct in_addr isaddr, itaddr, myaddr; u_int8_t *enaddr = NULL; int op; int bridged = 0, is_bridge = 0; int carped; struct sockaddr_in sin; struct sockaddr *dst; struct nhop4_basic nh4; uint8_t linkhdr[LLE_MAX_LINKHDR]; struct route ro; size_t linkhdrsize; int lladdr_off; int error; sin.sin_len = sizeof(struct sockaddr_in); sin.sin_family = AF_INET; sin.sin_addr.s_addr = 0; if (ifp->if_bridge) bridged = 1; if (ifp->if_type == IFT_BRIDGE) is_bridge = 1; /* * We already have checked that mbuf contains enough contiguous data * to hold entire arp message according to the arp header. */ ah = mtod(m, struct arphdr *); /* * ARP is only for IPv4 so we can reject packets with * a protocol length not equal to an IPv4 address. */ if (ah->ar_pln != sizeof(struct in_addr)) { ARP_LOG(LOG_NOTICE, "requested protocol length != %zu\n", sizeof(struct in_addr)); goto drop; } if (allow_multicast == 0 && ETHER_IS_MULTICAST(ar_sha(ah))) { ARP_LOG(LOG_NOTICE, "%*D is multicast\n", ifp->if_addrlen, (u_char *)ar_sha(ah), ":"); goto drop; } op = ntohs(ah->ar_op); (void)memcpy(&isaddr, ar_spa(ah), sizeof (isaddr)); (void)memcpy(&itaddr, ar_tpa(ah), sizeof (itaddr)); if (op == ARPOP_REPLY) ARPSTAT_INC(rxreplies); /* * For a bridge, we want to check the address irrespective * of the receive interface. (This will change slightly * when we have clusters of interfaces). */ IN_IFADDR_RLOCK(&in_ifa_tracker); LIST_FOREACH(ia, INADDR_HASH(itaddr.s_addr), ia_hash) { if (((bridged && ia->ia_ifp->if_bridge == ifp->if_bridge) || ia->ia_ifp == ifp) && itaddr.s_addr == ia->ia_addr.sin_addr.s_addr && (ia->ia_ifa.ifa_carp == NULL || (*carp_iamatch_p)(&ia->ia_ifa, &enaddr))) { ifa_ref(&ia->ia_ifa); IN_IFADDR_RUNLOCK(&in_ifa_tracker); goto match; } } LIST_FOREACH(ia, INADDR_HASH(isaddr.s_addr), ia_hash) if (((bridged && ia->ia_ifp->if_bridge == ifp->if_bridge) || ia->ia_ifp == ifp) && isaddr.s_addr == ia->ia_addr.sin_addr.s_addr) { ifa_ref(&ia->ia_ifa); IN_IFADDR_RUNLOCK(&in_ifa_tracker); goto match; } #define BDG_MEMBER_MATCHES_ARP(addr, ifp, ia) \ (ia->ia_ifp->if_bridge == ifp->if_softc && \ !bcmp(IF_LLADDR(ia->ia_ifp), IF_LLADDR(ifp), ifp->if_addrlen) && \ addr == ia->ia_addr.sin_addr.s_addr) /* * Check the case when bridge shares its MAC address with * some of its children, so packets are claimed by bridge * itself (bridge_input() does it first), but they are really * meant to be destined to the bridge member. */ if (is_bridge) { LIST_FOREACH(ia, INADDR_HASH(itaddr.s_addr), ia_hash) { if (BDG_MEMBER_MATCHES_ARP(itaddr.s_addr, ifp, ia)) { ifa_ref(&ia->ia_ifa); ifp = ia->ia_ifp; IN_IFADDR_RUNLOCK(&in_ifa_tracker); goto match; } } } #undef BDG_MEMBER_MATCHES_ARP IN_IFADDR_RUNLOCK(&in_ifa_tracker); /* * No match, use the first inet address on the receive interface * as a dummy address for the rest of the function. */ IF_ADDR_RLOCK(ifp); TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) if (ifa->ifa_addr->sa_family == AF_INET && (ifa->ifa_carp == NULL || (*carp_iamatch_p)(ifa, &enaddr))) { ia = ifatoia(ifa); ifa_ref(ifa); IF_ADDR_RUNLOCK(ifp); goto match; } IF_ADDR_RUNLOCK(ifp); /* * If bridging, fall back to using any inet address. */ IN_IFADDR_RLOCK(&in_ifa_tracker); if (!bridged || (ia = TAILQ_FIRST(&V_in_ifaddrhead)) == NULL) { IN_IFADDR_RUNLOCK(&in_ifa_tracker); goto drop; } ifa_ref(&ia->ia_ifa); IN_IFADDR_RUNLOCK(&in_ifa_tracker); match: if (!enaddr) enaddr = (u_int8_t *)IF_LLADDR(ifp); carped = (ia->ia_ifa.ifa_carp != NULL); myaddr = ia->ia_addr.sin_addr; ifa_free(&ia->ia_ifa); if (!bcmp(ar_sha(ah), enaddr, ifp->if_addrlen)) goto drop; /* it's from me, ignore it. */ if (!bcmp(ar_sha(ah), ifp->if_broadcastaddr, ifp->if_addrlen)) { ARP_LOG(LOG_NOTICE, "link address is broadcast for IP address " "%s!\n", inet_ntoa(isaddr)); goto drop; } if (ifp->if_addrlen != ah->ar_hln) { ARP_LOG(LOG_WARNING, "from %*D: addr len: new %d, " "i/f %d (ignored)\n", ifp->if_addrlen, (u_char *) ar_sha(ah), ":", ah->ar_hln, ifp->if_addrlen); goto drop; } /* * Warn if another host is using the same IP address, but only if the * IP address isn't 0.0.0.0, which is used for DHCP only, in which * case we suppress the warning to avoid false positive complaints of * potential misconfiguration. */ if (!bridged && !carped && isaddr.s_addr == myaddr.s_addr && myaddr.s_addr != 0) { ARP_LOG(LOG_ERR, "%*D is using my IP address %s on %s!\n", ifp->if_addrlen, (u_char *)ar_sha(ah), ":", inet_ntoa(isaddr), ifp->if_xname); itaddr = myaddr; ARPSTAT_INC(dupips); goto reply; } if (ifp->if_flags & IFF_STATICARP) goto reply; bzero(&sin, sizeof(sin)); sin.sin_len = sizeof(struct sockaddr_in); sin.sin_family = AF_INET; sin.sin_addr = isaddr; dst = (struct sockaddr *)&sin; IF_AFDATA_RLOCK(ifp); la = lla_lookup(LLTABLE(ifp), LLE_EXCLUSIVE, dst); IF_AFDATA_RUNLOCK(ifp); if (la != NULL) arp_check_update_lle(ah, isaddr, ifp, bridged, la); else if (itaddr.s_addr == myaddr.s_addr) { /* * Request/reply to our address, but no lle exists yet. * Calculate full link prepend to use in lle. */ linkhdrsize = sizeof(linkhdr); if (lltable_calc_llheader(ifp, AF_INET, ar_sha(ah), linkhdr, &linkhdrsize, &lladdr_off) != 0) goto reply; /* Allocate new entry */ la = lltable_alloc_entry(LLTABLE(ifp), 0, dst); if (la == NULL) { /* * lle creation may fail if source address belongs * to non-directly connected subnet. However, we * will try to answer the request instead of dropping * frame. */ goto reply; } lltable_set_entry_addr(ifp, la, linkhdr, linkhdrsize, lladdr_off); IF_AFDATA_WLOCK(ifp); LLE_WLOCK(la); la_tmp = lla_lookup(LLTABLE(ifp), LLE_EXCLUSIVE, dst); /* * Check if lle still does not exists. * If it does, that means that we either * 1) have configured it explicitly, via * 1a) 'arp -s' static entry or * 1b) interface address static record * or * 2) it was the result of sending first packet to-host * or * 3) it was another arp reply packet we handled in * different thread. * * In all cases except 3) we definitely need to prefer * existing lle. For the sake of simplicity, prefer any * existing lle over newly-create one. */ if (la_tmp == NULL) lltable_link_entry(LLTABLE(ifp), la); IF_AFDATA_WUNLOCK(ifp); if (la_tmp == NULL) { arp_mark_lle_reachable(la); LLE_WUNLOCK(la); } else { /* Free newly-create entry and handle packet */ lltable_free_entry(LLTABLE(ifp), la); la = la_tmp; la_tmp = NULL; arp_check_update_lle(ah, isaddr, ifp, bridged, la); /* arp_check_update_lle() returns @la unlocked */ } la = NULL; } reply: if (op != ARPOP_REQUEST) goto drop; ARPSTAT_INC(rxrequests); if (itaddr.s_addr == myaddr.s_addr) { /* Shortcut.. the receiving interface is the target. */ (void)memcpy(ar_tha(ah), ar_sha(ah), ah->ar_hln); (void)memcpy(ar_sha(ah), enaddr, ah->ar_hln); } else { struct llentry *lle = NULL; sin.sin_addr = itaddr; IF_AFDATA_RLOCK(ifp); lle = lla_lookup(LLTABLE(ifp), 0, (struct sockaddr *)&sin); IF_AFDATA_RUNLOCK(ifp); if ((lle != NULL) && (lle->la_flags & LLE_PUB)) { (void)memcpy(ar_tha(ah), ar_sha(ah), ah->ar_hln); (void)memcpy(ar_sha(ah), lle->ll_addr, ah->ar_hln); LLE_RUNLOCK(lle); } else { if (lle != NULL) LLE_RUNLOCK(lle); if (!V_arp_proxyall) goto drop; /* XXX MRT use table 0 for arp reply */ if (fib4_lookup_nh_basic(0, itaddr, 0, 0, &nh4) != 0) goto drop; /* * Don't send proxies for nodes on the same interface * as this one came out of, or we'll get into a fight * over who claims what Ether address. */ if (nh4.nh_ifp == ifp) goto drop; (void)memcpy(ar_tha(ah), ar_sha(ah), ah->ar_hln); (void)memcpy(ar_sha(ah), enaddr, ah->ar_hln); /* * Also check that the node which sent the ARP packet * is on the interface we expect it to be on. This * avoids ARP chaos if an interface is connected to the * wrong network. */ /* XXX MRT use table 0 for arp checks */ if (fib4_lookup_nh_basic(0, isaddr, 0, 0, &nh4) != 0) goto drop; if (nh4.nh_ifp != ifp) { ARP_LOG(LOG_INFO, "proxy: ignoring request" " from %s via %s\n", inet_ntoa(isaddr), ifp->if_xname); goto drop; } #ifdef DEBUG_PROXY printf("arp: proxying for %s\n", inet_ntoa(itaddr)); #endif } } if (itaddr.s_addr == myaddr.s_addr && IN_LINKLOCAL(ntohl(itaddr.s_addr))) { /* RFC 3927 link-local IPv4; always reply by broadcast. */ #ifdef DEBUG_LINKLOCAL printf("arp: sending reply for link-local addr %s\n", inet_ntoa(itaddr)); #endif m->m_flags |= M_BCAST; m->m_flags &= ~M_MCAST; } else { /* default behaviour; never reply by broadcast. */ m->m_flags &= ~(M_BCAST|M_MCAST); } (void)memcpy(ar_tpa(ah), ar_spa(ah), ah->ar_pln); (void)memcpy(ar_spa(ah), &itaddr, ah->ar_pln); ah->ar_op = htons(ARPOP_REPLY); ah->ar_pro = htons(ETHERTYPE_IP); /* let's be sure! */ m->m_len = sizeof(*ah) + (2 * ah->ar_pln) + (2 * ah->ar_hln); m->m_pkthdr.len = m->m_len; m->m_pkthdr.rcvif = NULL; sa.sa_family = AF_ARP; sa.sa_len = 2; /* Calculate link header for sending frame */ bzero(&ro, sizeof(ro)); linkhdrsize = sizeof(linkhdr); error = arp_fillheader(ifp, ah, 0, linkhdr, &linkhdrsize); /* * arp_fillheader() may fail due to lack of support inside encap request * routing. This is not necessary an error, AF_ARP can/should be handled * by if_output(). */ if (error != 0 && error != EAFNOSUPPORT) { ARP_LOG(LOG_ERR, "Failed to calculate ARP header on %s: %d\n", if_name(ifp), error); return; } ro.ro_prepend = linkhdr; ro.ro_plen = linkhdrsize; ro.ro_flags = 0; m_clrprotoflags(m); /* Avoid confusing lower layers. */ (*ifp->if_output)(ifp, m, &sa, &ro); ARPSTAT_INC(txreplies); return; drop: m_freem(m); } #endif /* * Checks received arp data against existing @la. * Updates lle state/performs notification if necessary. */ static void arp_check_update_lle(struct arphdr *ah, struct in_addr isaddr, struct ifnet *ifp, int bridged, struct llentry *la) { struct sockaddr sa; struct mbuf *m_hold, *m_hold_next; uint8_t linkhdr[LLE_MAX_LINKHDR]; size_t linkhdrsize; int lladdr_off; LLE_WLOCK_ASSERT(la); /* the following is not an error when doing bridging */ if (!bridged && la->lle_tbl->llt_ifp != ifp) { if (log_arp_wrong_iface) ARP_LOG(LOG_WARNING, "%s is on %s " "but got reply from %*D on %s\n", inet_ntoa(isaddr), la->lle_tbl->llt_ifp->if_xname, ifp->if_addrlen, (u_char *)ar_sha(ah), ":", ifp->if_xname); LLE_WUNLOCK(la); return; } if ((la->la_flags & LLE_VALID) && bcmp(ar_sha(ah), la->ll_addr, ifp->if_addrlen)) { if (la->la_flags & LLE_STATIC) { LLE_WUNLOCK(la); if (log_arp_permanent_modify) ARP_LOG(LOG_ERR, "%*D attempts to modify " "permanent entry for %s on %s\n", ifp->if_addrlen, (u_char *)ar_sha(ah), ":", inet_ntoa(isaddr), ifp->if_xname); return; } if (log_arp_movements) { ARP_LOG(LOG_INFO, "%s moved from %*D " "to %*D on %s\n", inet_ntoa(isaddr), ifp->if_addrlen, (u_char *)&la->ll_addr, ":", ifp->if_addrlen, (u_char *)ar_sha(ah), ":", ifp->if_xname); } } /* Calculate full link prepend to use in lle */ linkhdrsize = sizeof(linkhdr); if (lltable_calc_llheader(ifp, AF_INET, ar_sha(ah), linkhdr, &linkhdrsize, &lladdr_off) != 0) return; /* Check if something has changed */ if (memcmp(la->r_linkdata, linkhdr, linkhdrsize) != 0 || (la->la_flags & LLE_VALID) == 0) { /* Try to perform LLE update */ if (lltable_try_set_entry_addr(ifp, la, linkhdr, linkhdrsize, lladdr_off) == 0) return; /* Clear fast path feedback request if set */ la->r_skip_req = 0; } arp_mark_lle_reachable(la); /* * The packets are all freed within the call to the output * routine. * * NB: The lock MUST be released before the call to the * output routine. */ if (la->la_hold != NULL) { m_hold = la->la_hold; la->la_hold = NULL; la->la_numheld = 0; lltable_fill_sa_entry(la, &sa); LLE_WUNLOCK(la); for (; m_hold != NULL; m_hold = m_hold_next) { m_hold_next = m_hold->m_nextpkt; m_hold->m_nextpkt = NULL; /* Avoid confusing lower layers. */ m_clrprotoflags(m_hold); (*ifp->if_output)(ifp, m_hold, &sa, NULL); } } else LLE_WUNLOCK(la); } static void arp_mark_lle_reachable(struct llentry *la) { int canceled, wtime; LLE_WLOCK_ASSERT(la); la->ln_state = ARP_LLINFO_REACHABLE; EVENTHANDLER_INVOKE(lle_event, la, LLENTRY_RESOLVED); if (!(la->la_flags & LLE_STATIC)) { LLE_ADDREF(la); la->la_expire = time_uptime + V_arpt_keep; wtime = V_arpt_keep - V_arp_maxtries * V_arpt_rexmit; if (wtime < 0) wtime = V_arpt_keep; canceled = callout_reset(&la->lle_timer, hz * wtime, arptimer, la); if (canceled) LLE_REMREF(la); } la->la_asked = 0; la->la_preempt = V_arp_maxtries; } /* * Add pernament link-layer record for given interface address. */ static __noinline void arp_add_ifa_lle(struct ifnet *ifp, const struct sockaddr *dst) { struct llentry *lle, *lle_tmp; /* * Interface address LLE record is considered static * because kernel code relies on LLE_STATIC flag to check * if these entries can be rewriten by arp updates. */ lle = lltable_alloc_entry(LLTABLE(ifp), LLE_IFADDR | LLE_STATIC, dst); if (lle == NULL) { log(LOG_INFO, "arp_ifinit: cannot create arp " "entry for interface address\n"); return; } IF_AFDATA_WLOCK(ifp); LLE_WLOCK(lle); /* Unlink any entry if exists */ lle_tmp = lla_lookup(LLTABLE(ifp), LLE_EXCLUSIVE, dst); if (lle_tmp != NULL) lltable_unlink_entry(LLTABLE(ifp), lle_tmp); lltable_link_entry(LLTABLE(ifp), lle); IF_AFDATA_WUNLOCK(ifp); if (lle_tmp != NULL) EVENTHANDLER_INVOKE(lle_event, lle_tmp, LLENTRY_EXPIRED); EVENTHANDLER_INVOKE(lle_event, lle, LLENTRY_RESOLVED); LLE_WUNLOCK(lle); if (lle_tmp != NULL) lltable_free_entry(LLTABLE(ifp), lle_tmp); } void arp_ifinit(struct ifnet *ifp, struct ifaddr *ifa) { const struct sockaddr_in *dst_in; const struct sockaddr *dst; if (ifa->ifa_carp != NULL) return; dst = ifa->ifa_addr; dst_in = (const struct sockaddr_in *)dst; if (ntohl(dst_in->sin_addr.s_addr) == INADDR_ANY) return; arp_announce_ifaddr(ifp, dst_in->sin_addr, IF_LLADDR(ifp)); arp_add_ifa_lle(ifp, dst); } void arp_announce_ifaddr(struct ifnet *ifp, struct in_addr addr, u_char *enaddr) { if (ntohl(addr.s_addr) != INADDR_ANY) arprequest(ifp, &addr, &addr, enaddr); } /* * Sends gratuitous ARPs for each ifaddr to notify other * nodes about the address change. */ static __noinline void arp_handle_ifllchange(struct ifnet *ifp) { struct ifaddr *ifa; TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) { if (ifa->ifa_addr->sa_family == AF_INET) arp_ifinit(ifp, ifa); } } /* * A handler for interface link layer address change event. */ static void arp_iflladdr(void *arg __unused, struct ifnet *ifp) { lltable_update_ifaddr(LLTABLE(ifp)); if ((ifp->if_flags & IFF_UP) != 0) arp_handle_ifllchange(ifp); } static void arp_init(void) { netisr_register(&arp_nh); if (IS_DEFAULT_VNET(curvnet)) iflladdr_tag = EVENTHANDLER_REGISTER(iflladdr_event, arp_iflladdr, NULL, EVENTHANDLER_PRI_ANY); - if (IS_DEFAULT_VNET(curvnet)) - iflladdr_tag = EVENTHANDLER_REGISTER(iflladdr_event, - arp_iflladdr, NULL, EVENTHANDLER_PRI_ANY); } SYSINIT(arp, SI_SUB_PROTO_DOMAIN, SI_ORDER_ANY, arp_init, 0);