2 * SPDX-License-Identifier: BSD-3-Clause
4 * Copyright (c) 1982, 1989, 1993
5 * The Regents of the University of California. All rights reserved.
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 * 3. Neither the name of the University nor the names of its contributors
16 * may be used to endorse or promote products derived from this software
17 * without specific prior written permission.
19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 * @(#)if_ethersubr.c 8.1 (Berkeley) 6/10/93
36 #include "opt_inet6.h"
37 #include "opt_netgraph.h"
38 #include "opt_mbuf_profiling.h"
41 #include <sys/param.h>
42 #include <sys/systm.h>
44 #include <sys/eventhandler.h>
46 #include <sys/kernel.h>
48 #include <sys/malloc.h>
49 #include <sys/module.h>
53 #include <sys/random.h>
54 #include <sys/socket.h>
55 #include <sys/sockio.h>
56 #include <sys/sysctl.h>
59 #include <net/ieee_oui.h>
61 #include <net/if_var.h>
62 #include <net/if_arp.h>
63 #include <net/netisr.h>
64 #include <net/route.h>
65 #include <net/if_llc.h>
66 #include <net/if_dl.h>
67 #include <net/if_types.h>
69 #include <net/ethernet.h>
70 #include <net/if_bridgevar.h>
71 #include <net/if_vlan_var.h>
72 #include <net/if_llatbl.h>
74 #include <net/rss_config.h>
77 #include <netpfil/pf/pf_mtag.h>
79 #if defined(INET) || defined(INET6)
80 #include <netinet/in.h>
81 #include <netinet/in_var.h>
82 #include <netinet/if_ether.h>
83 #include <netinet/ip_carp.h>
84 #include <netinet/ip_var.h>
87 #include <netinet6/nd6.h>
89 #include <security/mac/mac_framework.h>
91 #include <crypto/sha1.h>
94 CTASSERT(sizeof (struct ether_header) == ETHER_ADDR_LEN * 2 + 2);
95 CTASSERT(sizeof (struct ether_addr) == ETHER_ADDR_LEN);
98 VNET_DEFINE(pfil_head_t, link_pfil_head); /* Packet filter hooks */
100 /* netgraph node hooks for ng_ether(4) */
101 void (*ng_ether_input_p)(struct ifnet *ifp, struct mbuf **mp);
102 void (*ng_ether_input_orphan_p)(struct ifnet *ifp, struct mbuf *m);
103 int (*ng_ether_output_p)(struct ifnet *ifp, struct mbuf **mp);
104 void (*ng_ether_attach_p)(struct ifnet *ifp);
105 void (*ng_ether_detach_p)(struct ifnet *ifp);
107 void (*vlan_input_p)(struct ifnet *, struct mbuf *);
109 /* if_bridge(4) support */
110 void (*bridge_dn_p)(struct mbuf *, struct ifnet *);
112 /* if_lagg(4) support */
113 struct mbuf *(*lagg_input_p)(struct ifnet *, struct mbuf *);
115 static const u_char etherbroadcastaddr[ETHER_ADDR_LEN] =
116 { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff };
118 static int ether_resolvemulti(struct ifnet *, struct sockaddr **,
121 static void ether_reassign(struct ifnet *, struct vnet *, char *);
123 static int ether_requestencap(struct ifnet *, struct if_encap_req *);
126 #define senderr(e) do { error = (e); goto bad;} while (0)
129 update_mbuf_csumflags(struct mbuf *src, struct mbuf *dst)
133 if (src->m_pkthdr.csum_flags & CSUM_IP)
134 csum_flags |= (CSUM_IP_CHECKED|CSUM_IP_VALID);
135 if (src->m_pkthdr.csum_flags & CSUM_DELAY_DATA)
136 csum_flags |= (CSUM_DATA_VALID|CSUM_PSEUDO_HDR);
137 if (src->m_pkthdr.csum_flags & CSUM_SCTP)
138 csum_flags |= CSUM_SCTP_VALID;
139 dst->m_pkthdr.csum_flags |= csum_flags;
140 if (csum_flags & CSUM_DATA_VALID)
141 dst->m_pkthdr.csum_data = 0xffff;
145 * Handle link-layer encapsulation requests.
148 ether_requestencap(struct ifnet *ifp, struct if_encap_req *req)
150 struct ether_header *eh;
153 const u_char *lladdr;
155 if (req->rtype != IFENCAP_LL)
158 if (req->bufsize < ETHER_HDR_LEN)
161 eh = (struct ether_header *)req->buf;
162 lladdr = req->lladdr;
165 switch (req->family) {
167 etype = htons(ETHERTYPE_IP);
170 etype = htons(ETHERTYPE_IPV6);
173 ah = (struct arphdr *)req->hdata;
174 ah->ar_hrd = htons(ARPHRD_ETHER);
176 switch(ntohs(ah->ar_op)) {
177 case ARPOP_REVREQUEST:
179 etype = htons(ETHERTYPE_REVARP);
184 etype = htons(ETHERTYPE_ARP);
188 if (req->flags & IFENCAP_FLAG_BROADCAST)
189 lladdr = ifp->if_broadcastaddr;
192 return (EAFNOSUPPORT);
195 memcpy(&eh->ether_type, &etype, sizeof(eh->ether_type));
196 memcpy(eh->ether_dhost, lladdr, ETHER_ADDR_LEN);
197 memcpy(eh->ether_shost, IF_LLADDR(ifp), ETHER_ADDR_LEN);
198 req->bufsize = sizeof(struct ether_header);
205 ether_resolve_addr(struct ifnet *ifp, struct mbuf *m,
206 const struct sockaddr *dst, struct route *ro, u_char *phdr,
207 uint32_t *pflags, struct llentry **plle)
209 struct ether_header *eh;
210 uint32_t lleflags = 0;
212 #if defined(INET) || defined(INET6)
218 eh = (struct ether_header *)phdr;
220 switch (dst->sa_family) {
223 if ((m->m_flags & (M_BCAST | M_MCAST)) == 0)
224 error = arpresolve(ifp, 0, m, dst, phdr, &lleflags,
227 if (m->m_flags & M_BCAST)
228 memcpy(eh->ether_dhost, ifp->if_broadcastaddr,
231 const struct in_addr *a;
232 a = &(((const struct sockaddr_in *)dst)->sin_addr);
233 ETHER_MAP_IP_MULTICAST(a, eh->ether_dhost);
235 etype = htons(ETHERTYPE_IP);
236 memcpy(&eh->ether_type, &etype, sizeof(etype));
237 memcpy(eh->ether_shost, IF_LLADDR(ifp), ETHER_ADDR_LEN);
243 if ((m->m_flags & M_MCAST) == 0)
244 error = nd6_resolve(ifp, 0, m, dst, phdr, &lleflags,
247 const struct in6_addr *a6;
248 a6 = &(((const struct sockaddr_in6 *)dst)->sin6_addr);
249 ETHER_MAP_IPV6_MULTICAST(a6, eh->ether_dhost);
250 etype = htons(ETHERTYPE_IPV6);
251 memcpy(&eh->ether_type, &etype, sizeof(etype));
252 memcpy(eh->ether_shost, IF_LLADDR(ifp), ETHER_ADDR_LEN);
257 if_printf(ifp, "can't handle af%d\n", dst->sa_family);
260 return (EAFNOSUPPORT);
263 if (error == EHOSTDOWN) {
264 if (ro != NULL && (ro->ro_flags & RT_HAS_GW) != 0)
265 error = EHOSTUNREACH;
271 *pflags = RT_MAY_LOOP;
272 if (lleflags & LLE_IFADDR)
279 * Ethernet output routine.
280 * Encapsulate a packet of type family for the local net.
281 * Use trailer local net encapsulation if enough data in first
282 * packet leaves a multiple of 512 bytes of data in remainder.
285 ether_output(struct ifnet *ifp, struct mbuf *m,
286 const struct sockaddr *dst, struct route *ro)
289 char linkhdr[ETHER_HDR_LEN], *phdr;
290 struct ether_header *eh;
293 int hlen; /* link layer header length */
295 struct llentry *lle = NULL;
301 /* XXX BPF uses ro_prepend */
302 if (ro->ro_prepend != NULL) {
303 phdr = ro->ro_prepend;
305 } else if (!(m->m_flags & (M_BCAST | M_MCAST))) {
306 if ((ro->ro_flags & RT_LLE_CACHE) != 0) {
309 (lle->la_flags & LLE_VALID) == 0) {
311 lle = NULL; /* redundant */
315 /* if we lookup, keep cache */
319 * Notify LLE code that
323 llentry_mark_used(lle);
326 phdr = lle->r_linkdata;
327 hlen = lle->r_hdrlen;
328 pflags = lle->r_flags;
334 error = mac_ifnet_check_transmit(ifp, m);
340 if (ifp->if_flags & IFF_MONITOR)
342 if (!((ifp->if_flags & IFF_UP) &&
343 (ifp->if_drv_flags & IFF_DRV_RUNNING)))
347 /* No prepend data supplied. Try to calculate ourselves. */
349 hlen = ETHER_HDR_LEN;
350 error = ether_resolve_addr(ifp, m, dst, ro, phdr, &pflags,
351 addref ? &lle : NULL);
352 if (addref && lle != NULL)
355 return (error == EWOULDBLOCK ? 0 : error);
358 if ((pflags & RT_L2_ME) != 0) {
359 update_mbuf_csumflags(m, m);
360 return (if_simloop(ifp, m, dst->sa_family, 0));
362 loop_copy = pflags & RT_MAY_LOOP;
365 * Add local net header. If no space in first mbuf,
368 * Note that we do prepend regardless of RT_HAS_HEADER flag.
369 * This is done because BPF code shifts m_data pointer
370 * to the end of ethernet header prior to calling if_output().
372 M_PREPEND(m, hlen, M_NOWAIT);
375 if ((pflags & RT_HAS_HEADER) == 0) {
376 eh = mtod(m, struct ether_header *);
377 memcpy(eh, phdr, hlen);
381 * If a simplex interface, and the packet is being sent to our
382 * Ethernet address or a broadcast address, loopback a copy.
383 * XXX To make a simplex device behave exactly like a duplex
384 * device, we should copy in the case of sending to our own
385 * ethernet address (thus letting the original actually appear
386 * on the wire). However, we don't do that here for security
387 * reasons and compatibility with the original behavior.
389 if ((m->m_flags & M_BCAST) && loop_copy && (ifp->if_flags & IFF_SIMPLEX) &&
390 ((t = pf_find_mtag(m)) == NULL || !t->routed)) {
394 * Because if_simloop() modifies the packet, we need a
395 * writable copy through m_dup() instead of a readonly
396 * one as m_copy[m] would give us. The alternative would
397 * be to modify if_simloop() to handle the readonly mbuf,
398 * but performancewise it is mostly equivalent (trading
399 * extra data copying vs. extra locking).
401 * XXX This is a local workaround. A number of less
402 * often used kernel parts suffer from the same bug.
403 * See PR kern/105943 for a proposed general solution.
405 if ((n = m_dup(m, M_NOWAIT)) != NULL) {
406 update_mbuf_csumflags(m, n);
407 (void)if_simloop(ifp, n, dst->sa_family, hlen);
409 if_inc_counter(ifp, IFCOUNTER_IQDROPS, 1);
413 * Bridges require special output handling.
415 if (ifp->if_bridge) {
416 BRIDGE_OUTPUT(ifp, m, error);
420 #if defined(INET) || defined(INET6)
422 (error = (*carp_output_p)(ifp, m, dst)))
426 /* Handle ng_ether(4) processing, if any */
427 if (ifp->if_l2com != NULL) {
428 KASSERT(ng_ether_output_p != NULL,
429 ("ng_ether_output_p is NULL"));
430 if ((error = (*ng_ether_output_p)(ifp, &m)) != 0) {
439 /* Continue with link-layer output */
440 return ether_output_frame(ifp, m);
444 ether_set_pcp(struct mbuf **mp, struct ifnet *ifp, uint8_t pcp)
446 struct ether_header *eh;
448 eh = mtod(*mp, struct ether_header *);
449 if (ntohs(eh->ether_type) == ETHERTYPE_VLAN ||
450 ether_8021q_frame(mp, ifp, ifp, 0, pcp))
452 if_inc_counter(ifp, IFCOUNTER_OERRORS, 1);
457 * Ethernet link layer output routine to send a raw frame to the device.
459 * This assumes that the 14 byte Ethernet header is present and contiguous
460 * in the first mbuf (if BRIDGE'ing).
463 ether_output_frame(struct ifnet *ifp, struct mbuf *m)
468 if (pcp != IFNET_PCP_NONE && ifp->if_type != IFT_L2VLAN &&
469 !ether_set_pcp(&m, ifp, pcp))
472 if (PFIL_HOOKED_OUT(V_link_pfil_head))
473 switch (pfil_run_hooks(V_link_pfil_head, &m, ifp, PFIL_OUT,
482 #if defined(INET6) && defined(INET)
483 /* draft-ietf-6man-ipv6only-flag */
484 /* Catch ETHERTYPE_IP, and ETHERTYPE_[REV]ARP if we are v6-only. */
485 if ((ND_IFINFO(ifp)->flags & ND6_IFF_IPV6_ONLY_MASK) != 0) {
486 struct ether_header *eh;
488 eh = mtod(m, struct ether_header *);
489 switch (ntohs(eh->ether_type)) {
492 case ETHERTYPE_REVARP:
494 return (EAFNOSUPPORT);
503 * Queue message on interface, update output statistics if
504 * successful, and start output if interface not yet active.
506 return ((ifp->if_transmit)(ifp, m));
510 * Process a received Ethernet packet; the packet is in the
511 * mbuf chain m with the ethernet header at the front.
514 ether_input_internal(struct ifnet *ifp, struct mbuf *m)
516 struct ether_header *eh;
519 if ((ifp->if_flags & IFF_UP) == 0) {
524 if ((ifp->if_drv_flags & IFF_DRV_RUNNING) == 0) {
525 if_printf(ifp, "discard frame at !IFF_DRV_RUNNING\n");
530 if (m->m_len < ETHER_HDR_LEN) {
531 /* XXX maybe should pullup? */
532 if_printf(ifp, "discard frame w/o leading ethernet "
533 "header (len %u pkt len %u)\n",
534 m->m_len, m->m_pkthdr.len);
535 if_inc_counter(ifp, IFCOUNTER_IERRORS, 1);
539 eh = mtod(m, struct ether_header *);
540 etype = ntohs(eh->ether_type);
541 random_harvest_queue_ether(m, sizeof(*m));
544 #if defined(INET6) && defined(INET)
545 /* draft-ietf-6man-ipv6only-flag */
546 /* Catch ETHERTYPE_IP, and ETHERTYPE_[REV]ARP if we are v6-only. */
547 if ((ND_IFINFO(ifp)->flags & ND6_IFF_IPV6_ONLY_MASK) != 0) {
552 case ETHERTYPE_REVARP:
562 CURVNET_SET_QUIET(ifp->if_vnet);
564 if (ETHER_IS_MULTICAST(eh->ether_dhost)) {
565 if (ETHER_IS_BROADCAST(eh->ether_dhost))
566 m->m_flags |= M_BCAST;
568 m->m_flags |= M_MCAST;
569 if_inc_counter(ifp, IFCOUNTER_IMCASTS, 1);
574 * Tag the mbuf with an appropriate MAC label before any other
575 * consumers can get to it.
577 mac_ifnet_create_mbuf(ifp, m);
581 * Give bpf a chance at the packet.
583 ETHER_BPF_MTAP(ifp, m);
586 * If the CRC is still on the packet, trim it off. We do this once
587 * and once only in case we are re-entered. Nothing else on the
588 * Ethernet receive path expects to see the FCS.
590 if (m->m_flags & M_HASFCS) {
591 m_adj(m, -ETHER_CRC_LEN);
592 m->m_flags &= ~M_HASFCS;
595 if (!(ifp->if_capenable & IFCAP_HWSTATS))
596 if_inc_counter(ifp, IFCOUNTER_IBYTES, m->m_pkthdr.len);
598 /* Allow monitor mode to claim this frame, after stats are updated. */
599 if (ifp->if_flags & IFF_MONITOR) {
605 /* Handle input from a lagg(4) port */
606 if (ifp->if_type == IFT_IEEE8023ADLAG) {
607 KASSERT(lagg_input_p != NULL,
608 ("%s: if_lagg not loaded!", __func__));
609 m = (*lagg_input_p)(ifp, m);
611 ifp = m->m_pkthdr.rcvif;
619 * If the hardware did not process an 802.1Q tag, do this now,
620 * to allow 802.1P priority frames to be passed to the main input
622 * TODO: Deal with Q-in-Q frames, but not arbitrary nesting levels.
624 if ((m->m_flags & M_VLANTAG) == 0 && etype == ETHERTYPE_VLAN) {
625 struct ether_vlan_header *evl;
627 if (m->m_len < sizeof(*evl) &&
628 (m = m_pullup(m, sizeof(*evl))) == NULL) {
630 if_printf(ifp, "cannot pullup VLAN header\n");
632 if_inc_counter(ifp, IFCOUNTER_IERRORS, 1);
637 evl = mtod(m, struct ether_vlan_header *);
638 m->m_pkthdr.ether_vtag = ntohs(evl->evl_tag);
639 m->m_flags |= M_VLANTAG;
641 bcopy((char *)evl, (char *)evl + ETHER_VLAN_ENCAP_LEN,
642 ETHER_HDR_LEN - ETHER_TYPE_LEN);
643 m_adj(m, ETHER_VLAN_ENCAP_LEN);
644 eh = mtod(m, struct ether_header *);
647 M_SETFIB(m, ifp->if_fib);
649 /* Allow ng_ether(4) to claim this frame. */
650 if (ifp->if_l2com != NULL) {
651 KASSERT(ng_ether_input_p != NULL,
652 ("%s: ng_ether_input_p is NULL", __func__));
653 m->m_flags &= ~M_PROMISC;
654 (*ng_ether_input_p)(ifp, &m);
659 eh = mtod(m, struct ether_header *);
663 * Allow if_bridge(4) to claim this frame.
664 * The BRIDGE_INPUT() macro will update ifp if the bridge changed it
665 * and the frame should be delivered locally.
667 if (ifp->if_bridge != NULL) {
668 m->m_flags &= ~M_PROMISC;
669 BRIDGE_INPUT(ifp, m);
674 eh = mtod(m, struct ether_header *);
677 #if defined(INET) || defined(INET6)
679 * Clear M_PROMISC on frame so that carp(4) will see it when the
680 * mbuf flows up to Layer 3.
681 * FreeBSD's implementation of carp(4) uses the inprotosw
682 * to dispatch IPPROTO_CARP. carp(4) also allocates its own
683 * Ethernet addresses of the form 00:00:5e:00:01:xx, which
684 * is outside the scope of the M_PROMISC test below.
685 * TODO: Maintain a hash table of ethernet addresses other than
686 * ether_dhost which may be active on this ifp.
688 if (ifp->if_carp && (*carp_forus_p)(ifp, eh->ether_dhost)) {
689 m->m_flags &= ~M_PROMISC;
694 * If the frame received was not for our MAC address, set the
695 * M_PROMISC flag on the mbuf chain. The frame may need to
696 * be seen by the rest of the Ethernet input path in case of
697 * re-entry (e.g. bridge, vlan, netgraph) but should not be
698 * seen by upper protocol layers.
700 if (!ETHER_IS_MULTICAST(eh->ether_dhost) &&
701 bcmp(IF_LLADDR(ifp), eh->ether_dhost, ETHER_ADDR_LEN) != 0)
702 m->m_flags |= M_PROMISC;
710 * Ethernet input dispatch; by default, direct dispatch here regardless of
711 * global configuration. However, if RSS is enabled, hook up RSS affinity
712 * so that when deferred or hybrid dispatch is enabled, we can redistribute
715 * XXXRW: Would be nice if the ifnet passed up a flag indicating whether or
716 * not it had already done work distribution via multi-queue. Then we could
717 * direct dispatch in the event load balancing was already complete and
718 * handle the case of interfaces with different capabilities better.
720 * XXXRW: Sort of want an M_DISTRIBUTED flag to avoid multiple distributions
721 * at multiple layers?
723 * XXXRW: For now, enable all this only if RSS is compiled in, although it
724 * works fine without RSS. Need to characterise the performance overhead
725 * of the detour through the netisr code in the event the result is always
729 ether_nh_input(struct mbuf *m)
733 KASSERT(m->m_pkthdr.rcvif != NULL,
734 ("%s: NULL interface pointer", __func__));
735 ether_input_internal(m->m_pkthdr.rcvif, m);
738 static struct netisr_handler ether_nh = {
740 .nh_handler = ether_nh_input,
741 .nh_proto = NETISR_ETHER,
743 .nh_policy = NETISR_POLICY_CPU,
744 .nh_dispatch = NETISR_DISPATCH_DIRECT,
745 .nh_m2cpuid = rss_m2cpuid,
747 .nh_policy = NETISR_POLICY_SOURCE,
748 .nh_dispatch = NETISR_DISPATCH_DIRECT,
753 ether_init(__unused void *arg)
756 netisr_register(ðer_nh);
758 SYSINIT(ether, SI_SUB_INIT_IF, SI_ORDER_ANY, ether_init, NULL);
761 vnet_ether_init(__unused void *arg)
763 struct pfil_head_args args;
765 args.pa_version = PFIL_VERSION;
766 args.pa_flags = PFIL_IN | PFIL_OUT;
767 args.pa_type = PFIL_TYPE_ETHERNET;
768 args.pa_headname = PFIL_ETHER_NAME;
769 V_link_pfil_head = pfil_head_register(&args);
772 netisr_register_vnet(ðer_nh);
775 VNET_SYSINIT(vnet_ether_init, SI_SUB_PROTO_IF, SI_ORDER_ANY,
776 vnet_ether_init, NULL);
780 vnet_ether_pfil_destroy(__unused void *arg)
783 pfil_head_unregister(V_link_pfil_head);
785 VNET_SYSUNINIT(vnet_ether_pfil_uninit, SI_SUB_PROTO_PFIL, SI_ORDER_ANY,
786 vnet_ether_pfil_destroy, NULL);
789 vnet_ether_destroy(__unused void *arg)
792 netisr_unregister_vnet(ðer_nh);
794 VNET_SYSUNINIT(vnet_ether_uninit, SI_SUB_PROTO_IF, SI_ORDER_ANY,
795 vnet_ether_destroy, NULL);
801 ether_input(struct ifnet *ifp, struct mbuf *m)
807 * The drivers are allowed to pass in a chain of packets linked with
808 * m_nextpkt. We split them up into separate packets here and pass
809 * them up. This allows the drivers to amortize the receive lock.
816 * We will rely on rcvif being set properly in the deferred context,
817 * so assert it is correct here.
819 MPASS((m->m_pkthdr.csum_flags & CSUM_SND_TAG) == 0);
820 KASSERT(m->m_pkthdr.rcvif == ifp, ("%s: ifnet mismatch m %p "
821 "rcvif %p ifp %p", __func__, m, m->m_pkthdr.rcvif, ifp));
822 CURVNET_SET_QUIET(ifp->if_vnet);
823 netisr_dispatch(NETISR_ETHER, m);
830 * Upper layer processing for a received Ethernet packet.
833 ether_demux(struct ifnet *ifp, struct mbuf *m)
835 struct ether_header *eh;
839 KASSERT(ifp != NULL, ("%s: NULL interface pointer", __func__));
841 /* Do not grab PROMISC frames in case we are re-entered. */
842 if (PFIL_HOOKED_IN(V_link_pfil_head) && !(m->m_flags & M_PROMISC)) {
843 i = pfil_run_hooks(V_link_pfil_head, &m, ifp, PFIL_IN, NULL);
844 if (i != 0 || m == NULL)
848 eh = mtod(m, struct ether_header *);
849 ether_type = ntohs(eh->ether_type);
852 * If this frame has a VLAN tag other than 0, call vlan_input()
853 * if its module is loaded. Otherwise, drop.
855 if ((m->m_flags & M_VLANTAG) &&
856 EVL_VLANOFTAG(m->m_pkthdr.ether_vtag) != 0) {
857 if (ifp->if_vlantrunk == NULL) {
858 if_inc_counter(ifp, IFCOUNTER_NOPROTO, 1);
862 KASSERT(vlan_input_p != NULL,("%s: VLAN not loaded!",
864 /* Clear before possibly re-entering ether_input(). */
865 m->m_flags &= ~M_PROMISC;
866 (*vlan_input_p)(ifp, m);
871 * Pass promiscuously received frames to the upper layer if the user
872 * requested this by setting IFF_PPROMISC. Otherwise, drop them.
874 if ((ifp->if_flags & IFF_PPROMISC) == 0 && (m->m_flags & M_PROMISC)) {
880 * Reset layer specific mbuf flags to avoid confusing upper layers.
881 * Strip off Ethernet header.
883 m->m_flags &= ~M_VLANTAG;
885 m_adj(m, ETHER_HDR_LEN);
888 * Dispatch frame to upper layer.
890 switch (ether_type) {
897 if (ifp->if_flags & IFF_NOARP) {
898 /* Discard packet if ARP is disabled on interface */
913 netisr_dispatch(isr, m);
918 * Packet is to be discarded. If netgraph is present,
919 * hand the packet to it for last chance processing;
920 * otherwise dispose of it.
922 if (ifp->if_l2com != NULL) {
923 KASSERT(ng_ether_input_orphan_p != NULL,
924 ("ng_ether_input_orphan_p is NULL"));
926 * Put back the ethernet header so netgraph has a
927 * consistent view of inbound packets.
929 M_PREPEND(m, ETHER_HDR_LEN, M_NOWAIT);
930 (*ng_ether_input_orphan_p)(ifp, m);
937 * Convert Ethernet address to printable (loggable) representation.
938 * This routine is for compatibility; it's better to just use
940 * printf("%6D", <pointer to address>, ":");
942 * since there's no static buffer involved.
945 ether_sprintf(const u_char *ap)
947 static char etherbuf[18];
948 snprintf(etherbuf, sizeof (etherbuf), "%6D", ap, ":");
953 * Perform common duties while attaching to interface list
956 ether_ifattach(struct ifnet *ifp, const u_int8_t *lla)
960 struct sockaddr_dl *sdl;
962 ifp->if_addrlen = ETHER_ADDR_LEN;
963 ifp->if_hdrlen = ETHER_HDR_LEN;
965 ifp->if_mtu = ETHERMTU;
966 ifp->if_output = ether_output;
967 ifp->if_input = ether_input;
968 ifp->if_resolvemulti = ether_resolvemulti;
969 ifp->if_requestencap = ether_requestencap;
971 ifp->if_reassign = ether_reassign;
973 if (ifp->if_baudrate == 0)
974 ifp->if_baudrate = IF_Mbps(10); /* just a default */
975 ifp->if_broadcastaddr = etherbroadcastaddr;
978 KASSERT(ifa != NULL, ("%s: no lladdr!\n", __func__));
979 sdl = (struct sockaddr_dl *)ifa->ifa_addr;
980 sdl->sdl_type = IFT_ETHER;
981 sdl->sdl_alen = ifp->if_addrlen;
982 bcopy(lla, LLADDR(sdl), ifp->if_addrlen);
984 if (ifp->if_hw_addr != NULL)
985 bcopy(lla, ifp->if_hw_addr, ifp->if_addrlen);
987 bpfattach(ifp, DLT_EN10MB, ETHER_HDR_LEN);
988 if (ng_ether_attach_p != NULL)
989 (*ng_ether_attach_p)(ifp);
991 /* Announce Ethernet MAC address if non-zero. */
992 for (i = 0; i < ifp->if_addrlen; i++)
995 if (i != ifp->if_addrlen)
996 if_printf(ifp, "Ethernet address: %6D\n", lla, ":");
998 uuid_ether_add(LLADDR(sdl));
1000 /* Add necessary bits are setup; announce it now. */
1001 EVENTHANDLER_INVOKE(ether_ifattach_event, ifp);
1002 if (IS_DEFAULT_VNET(curvnet))
1003 devctl_notify("ETHERNET", ifp->if_xname, "IFATTACH", NULL);
1007 * Perform common duties while detaching an Ethernet interface
1010 ether_ifdetach(struct ifnet *ifp)
1012 struct sockaddr_dl *sdl;
1014 sdl = (struct sockaddr_dl *)(ifp->if_addr->ifa_addr);
1015 uuid_ether_del(LLADDR(sdl));
1017 if (ifp->if_l2com != NULL) {
1018 KASSERT(ng_ether_detach_p != NULL,
1019 ("ng_ether_detach_p is NULL"));
1020 (*ng_ether_detach_p)(ifp);
1029 ether_reassign(struct ifnet *ifp, struct vnet *new_vnet, char *unused __unused)
1032 if (ifp->if_l2com != NULL) {
1033 KASSERT(ng_ether_detach_p != NULL,
1034 ("ng_ether_detach_p is NULL"));
1035 (*ng_ether_detach_p)(ifp);
1038 if (ng_ether_attach_p != NULL) {
1039 CURVNET_SET_QUIET(new_vnet);
1040 (*ng_ether_attach_p)(ifp);
1046 SYSCTL_DECL(_net_link);
1047 SYSCTL_NODE(_net_link, IFT_ETHER, ether, CTLFLAG_RW, 0, "Ethernet");
1051 * This is for reference. We have a table-driven version
1052 * of the little-endian crc32 generator, which is faster
1053 * than the double-loop.
1056 ether_crc32_le(const uint8_t *buf, size_t len)
1063 crc = 0xffffffff; /* initial value */
1065 for (i = 0; i < len; i++) {
1066 for (data = *buf++, bit = 0; bit < 8; bit++, data >>= 1) {
1067 carry = (crc ^ data) & 1;
1070 crc = (crc ^ ETHER_CRC_POLY_LE);
1078 ether_crc32_le(const uint8_t *buf, size_t len)
1080 static const uint32_t crctab[] = {
1081 0x00000000, 0x1db71064, 0x3b6e20c8, 0x26d930ac,
1082 0x76dc4190, 0x6b6b51f4, 0x4db26158, 0x5005713c,
1083 0xedb88320, 0xf00f9344, 0xd6d6a3e8, 0xcb61b38c,
1084 0x9b64c2b0, 0x86d3d2d4, 0xa00ae278, 0xbdbdf21c
1089 crc = 0xffffffff; /* initial value */
1091 for (i = 0; i < len; i++) {
1093 crc = (crc >> 4) ^ crctab[crc & 0xf];
1094 crc = (crc >> 4) ^ crctab[crc & 0xf];
1102 ether_crc32_be(const uint8_t *buf, size_t len)
1105 uint32_t crc, carry;
1109 crc = 0xffffffff; /* initial value */
1111 for (i = 0; i < len; i++) {
1112 for (data = *buf++, bit = 0; bit < 8; bit++, data >>= 1) {
1113 carry = ((crc & 0x80000000) ? 1 : 0) ^ (data & 0x01);
1116 crc = (crc ^ ETHER_CRC_POLY_BE) | carry;
1124 ether_ioctl(struct ifnet *ifp, u_long command, caddr_t data)
1126 struct ifaddr *ifa = (struct ifaddr *) data;
1127 struct ifreq *ifr = (struct ifreq *) data;
1132 ifp->if_flags |= IFF_UP;
1134 switch (ifa->ifa_addr->sa_family) {
1137 ifp->if_init(ifp->if_softc); /* before arpwhohas */
1138 arp_ifinit(ifp, ifa);
1142 ifp->if_init(ifp->if_softc);
1148 bcopy(IF_LLADDR(ifp), &ifr->ifr_addr.sa_data[0],
1154 * Set the interface MTU.
1156 if (ifr->ifr_mtu > ETHERMTU) {
1159 ifp->if_mtu = ifr->ifr_mtu;
1164 error = priv_check(curthread, PRIV_NET_SETLANPCP);
1167 if (ifr->ifr_lan_pcp > 7 &&
1168 ifr->ifr_lan_pcp != IFNET_PCP_NONE) {
1171 ifp->if_pcp = ifr->ifr_lan_pcp;
1172 /* broadcast event about PCP change */
1173 EVENTHANDLER_INVOKE(ifnet_event, ifp, IFNET_EVENT_PCP);
1178 ifr->ifr_lan_pcp = ifp->if_pcp;
1182 error = EINVAL; /* XXX netbsd has ENOTTY??? */
1189 ether_resolvemulti(struct ifnet *ifp, struct sockaddr **llsa,
1190 struct sockaddr *sa)
1192 struct sockaddr_dl *sdl;
1194 struct sockaddr_in *sin;
1197 struct sockaddr_in6 *sin6;
1201 switch(sa->sa_family) {
1204 * No mapping needed. Just check that it's a valid MC address.
1206 sdl = (struct sockaddr_dl *)sa;
1207 e_addr = LLADDR(sdl);
1208 if (!ETHER_IS_MULTICAST(e_addr))
1209 return EADDRNOTAVAIL;
1215 sin = (struct sockaddr_in *)sa;
1216 if (!IN_MULTICAST(ntohl(sin->sin_addr.s_addr)))
1217 return EADDRNOTAVAIL;
1218 sdl = link_init_sdl(ifp, *llsa, IFT_ETHER);
1219 sdl->sdl_alen = ETHER_ADDR_LEN;
1220 e_addr = LLADDR(sdl);
1221 ETHER_MAP_IP_MULTICAST(&sin->sin_addr, e_addr);
1222 *llsa = (struct sockaddr *)sdl;
1227 sin6 = (struct sockaddr_in6 *)sa;
1228 if (IN6_IS_ADDR_UNSPECIFIED(&sin6->sin6_addr)) {
1230 * An IP6 address of 0 means listen to all
1231 * of the Ethernet multicast address used for IP6.
1232 * (This is used for multicast routers.)
1234 ifp->if_flags |= IFF_ALLMULTI;
1238 if (!IN6_IS_ADDR_MULTICAST(&sin6->sin6_addr))
1239 return EADDRNOTAVAIL;
1240 sdl = link_init_sdl(ifp, *llsa, IFT_ETHER);
1241 sdl->sdl_alen = ETHER_ADDR_LEN;
1242 e_addr = LLADDR(sdl);
1243 ETHER_MAP_IPV6_MULTICAST(&sin6->sin6_addr, e_addr);
1244 *llsa = (struct sockaddr *)sdl;
1250 * Well, the text isn't quite right, but it's the name
1253 return EAFNOSUPPORT;
1257 static moduledata_t ether_mod = {
1262 ether_vlan_mtap(struct bpf_if *bp, struct mbuf *m, void *data, u_int dlen)
1264 struct ether_vlan_header vlan;
1267 KASSERT((m->m_flags & M_VLANTAG) != 0,
1268 ("%s: vlan information not present", __func__));
1269 KASSERT(m->m_len >= sizeof(struct ether_header),
1270 ("%s: mbuf not large enough for header", __func__));
1271 bcopy(mtod(m, char *), &vlan, sizeof(struct ether_header));
1272 vlan.evl_proto = vlan.evl_encap_proto;
1273 vlan.evl_encap_proto = htons(ETHERTYPE_VLAN);
1274 vlan.evl_tag = htons(m->m_pkthdr.ether_vtag);
1275 m->m_len -= sizeof(struct ether_header);
1276 m->m_data += sizeof(struct ether_header);
1278 * If a data link has been supplied by the caller, then we will need to
1279 * re-create a stack allocated mbuf chain with the following structure:
1281 * (1) mbuf #1 will contain the supplied data link
1282 * (2) mbuf #2 will contain the vlan header
1283 * (3) mbuf #3 will contain the original mbuf's packet data
1285 * Otherwise, submit the packet and vlan header via bpf_mtap2().
1289 mv.m_data = (caddr_t)&vlan;
1290 mv.m_len = sizeof(vlan);
1296 bpf_mtap2(bp, &vlan, sizeof(vlan), m);
1297 m->m_len += sizeof(struct ether_header);
1298 m->m_data -= sizeof(struct ether_header);
1302 ether_vlanencap(struct mbuf *m, uint16_t tag)
1304 struct ether_vlan_header *evl;
1306 M_PREPEND(m, ETHER_VLAN_ENCAP_LEN, M_NOWAIT);
1309 /* M_PREPEND takes care of m_len, m_pkthdr.len for us */
1311 if (m->m_len < sizeof(*evl)) {
1312 m = m_pullup(m, sizeof(*evl));
1318 * Transform the Ethernet header into an Ethernet header
1319 * with 802.1Q encapsulation.
1321 evl = mtod(m, struct ether_vlan_header *);
1322 bcopy((char *)evl + ETHER_VLAN_ENCAP_LEN,
1323 (char *)evl, ETHER_HDR_LEN - ETHER_TYPE_LEN);
1324 evl->evl_encap_proto = htons(ETHERTYPE_VLAN);
1325 evl->evl_tag = htons(tag);
1329 static SYSCTL_NODE(_net_link, IFT_L2VLAN, vlan, CTLFLAG_RW, 0,
1330 "IEEE 802.1Q VLAN");
1331 static SYSCTL_NODE(_net_link_vlan, PF_LINK, link, CTLFLAG_RW, 0,
1334 VNET_DEFINE_STATIC(int, soft_pad);
1335 #define V_soft_pad VNET(soft_pad)
1336 SYSCTL_INT(_net_link_vlan, OID_AUTO, soft_pad, CTLFLAG_RW | CTLFLAG_VNET,
1337 &VNET_NAME(soft_pad), 0,
1338 "pad short frames before tagging");
1341 * For now, make preserving PCP via an mbuf tag optional, as it increases
1342 * per-packet memory allocations and frees. In the future, it would be
1343 * preferable to reuse ether_vtag for this, or similar.
1345 int vlan_mtag_pcp = 0;
1346 SYSCTL_INT(_net_link_vlan, OID_AUTO, mtag_pcp, CTLFLAG_RW,
1348 "Retain VLAN PCP information as packets are passed up the stack");
1351 ether_8021q_frame(struct mbuf **mp, struct ifnet *ife, struct ifnet *p,
1352 uint16_t vid, uint8_t pcp)
1357 static const char pad[8]; /* just zeros */
1360 * Pad the frame to the minimum size allowed if told to.
1361 * This option is in accord with IEEE Std 802.1Q, 2003 Ed.,
1362 * paragraph C.4.4.3.b. It can help to work around buggy
1363 * bridges that violate paragraph C.4.4.3.a from the same
1364 * document, i.e., fail to pad short frames after untagging.
1365 * E.g., a tagged frame 66 bytes long (incl. FCS) is OK, but
1366 * untagging it will produce a 62-byte frame, which is a runt
1367 * and requires padding. There are VLAN-enabled network
1368 * devices that just discard such runts instead or mishandle
1371 if (V_soft_pad && p->if_type == IFT_ETHER) {
1372 for (n = ETHERMIN + ETHER_HDR_LEN - (*mp)->m_pkthdr.len;
1373 n > 0; n -= sizeof(pad)) {
1374 if (!m_append(*mp, min(n, sizeof(pad)), pad))
1380 if_printf(ife, "cannot pad short frame");
1386 * If underlying interface can do VLAN tag insertion itself,
1387 * just pass the packet along. However, we need some way to
1388 * tell the interface where the packet came from so that it
1389 * knows how to find the VLAN tag to use, so we attach a
1390 * packet tag that holds it.
1392 if (vlan_mtag_pcp && (mtag = m_tag_locate(*mp, MTAG_8021Q,
1393 MTAG_8021Q_PCP_OUT, NULL)) != NULL)
1394 tag = EVL_MAKETAG(vid, *(uint8_t *)(mtag + 1), 0);
1396 tag = EVL_MAKETAG(vid, pcp, 0);
1397 if (p->if_capenable & IFCAP_VLAN_HWTAGGING) {
1398 (*mp)->m_pkthdr.ether_vtag = tag;
1399 (*mp)->m_flags |= M_VLANTAG;
1401 *mp = ether_vlanencap(*mp, tag);
1403 if_printf(ife, "unable to prepend 802.1Q header");
1411 * Allocate an address from the FreeBSD Foundation OUI. This uses a
1412 * cryptographic hash function on the containing jail's UUID and the interface
1413 * name to attempt to provide a unique but stable address. Pseudo-interfaces
1414 * which require a MAC address should use this function to allocate
1415 * non-locally-administered addresses.
1418 ether_gen_addr(struct ifnet *ifp, struct ether_addr *hwaddr)
1420 #define ETHER_GEN_ADDR_BUFSIZ HOSTUUIDLEN + IFNAMSIZ + 2
1422 char buf[ETHER_GEN_ADDR_BUFSIZ];
1423 char uuid[HOSTUUIDLEN + 1];
1426 char digest[SHA1_RESULTLEN];
1428 getcredhostuuid(curthread->td_ucred, uuid, sizeof(uuid));
1429 sz = snprintf(buf, ETHER_GEN_ADDR_BUFSIZ, "%s-%s", uuid, ifp->if_xname);
1431 SHA1Update(&ctx, buf, sz);
1432 SHA1Final(digest, &ctx);
1434 addr = ((digest[0] << 16) | (digest[1] << 8) | digest[2]) &
1435 OUI_FREEBSD_GENERATED_MASK;
1436 addr = OUI_FREEBSD(addr);
1437 for (i = 0; i < ETHER_ADDR_LEN; ++i) {
1438 hwaddr->octet[i] = addr >> ((ETHER_ADDR_LEN - i - 1) * 8) &
1443 DECLARE_MODULE(ether, ether_mod, SI_SUB_INIT_IF, SI_ORDER_ANY);
1444 MODULE_VERSION(ether, 1);