2 * Copyright (c) 2004, 2005 The DragonFly Project. All rights reserved.
4 * This code is derived from software contributed to The DragonFly Project
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
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38 * modification, are permitted provided that the following conditions
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65 * @(#)if_ether.c 8.1 (Berkeley) 6/10/93
66 * $FreeBSD: src/sys/netinet/if_ether.c,v 1.64.2.23 2003/04/11 07:23:15 fjoe Exp $
67 * $DragonFly: src/sys/netinet/if_ether.c,v 1.45 2008/03/07 11:34:20 sephe Exp $
71 * Ethernet address resolution protocol.
73 * add "inuse/lock" bit (or ref. count) along with valid bit
79 #include <sys/param.h>
80 #include <sys/kernel.h>
81 #include <sys/queue.h>
82 #include <sys/sysctl.h>
83 #include <sys/systm.h>
85 #include <sys/malloc.h>
86 #include <sys/socket.h>
87 #include <sys/syslog.h>
90 #include <net/if_dl.h>
91 #include <net/if_types.h>
92 #include <net/route.h>
93 #include <net/netisr.h>
94 #include <net/if_llc.h>
96 #include <netinet/in.h>
97 #include <netinet/in_var.h>
98 #include <netinet/if_ether.h>
100 #include <sys/thread2.h>
101 #include <sys/msgport2.h>
102 #include <net/netmsg2.h>
106 #include <netinet/ip_carp.h>
109 #define SIN(s) ((struct sockaddr_in *)s)
110 #define SDL(s) ((struct sockaddr_dl *)s)
112 SYSCTL_DECL(_net_link_ether);
113 SYSCTL_NODE(_net_link_ether, PF_INET, inet, CTLFLAG_RW, 0, "");
116 static int arpt_prune = (5*60*1); /* walk list every 5 minutes */
117 static int arpt_keep = (20*60); /* once resolved, good for 20 more minutes */
118 static int arpt_down = 20; /* once declared down, don't send for 20 sec */
120 SYSCTL_INT(_net_link_ether_inet, OID_AUTO, prune_intvl, CTLFLAG_RW,
122 SYSCTL_INT(_net_link_ether_inet, OID_AUTO, max_age, CTLFLAG_RW,
124 SYSCTL_INT(_net_link_ether_inet, OID_AUTO, host_down_time, CTLFLAG_RW,
127 #define rt_expire rt_rmx.rmx_expire
130 LIST_ENTRY(llinfo_arp) la_le;
131 struct rtentry *la_rt;
132 struct mbuf *la_hold; /* last packet until resolved/timeout */
133 u_short la_preempt; /* countdown for pre-expiry arps */
134 u_short la_asked; /* #times we QUERIED following expiration */
137 static LIST_HEAD(, llinfo_arp) llinfo_arp_list[MAXCPU];
139 static int arp_maxtries = 5;
140 static int useloopback = 1; /* use loopback interface for local traffic */
141 static int arp_proxyall = 0;
143 SYSCTL_INT(_net_link_ether_inet, OID_AUTO, maxtries, CTLFLAG_RW,
144 &arp_maxtries, 0, "");
145 SYSCTL_INT(_net_link_ether_inet, OID_AUTO, useloopback, CTLFLAG_RW,
146 &useloopback, 0, "");
147 SYSCTL_INT(_net_link_ether_inet, OID_AUTO, proxyall, CTLFLAG_RW,
148 &arp_proxyall, 0, "");
150 void arprequest_acces(struct ifnet *ifp, struct in_addr *sip, struct in_addr *tip, u_char *enaddr);
151 static void arp_rtrequest (int, struct rtentry *, struct rt_addrinfo *);
152 static void arprequest (struct ifnet *,
153 struct in_addr *, struct in_addr *, u_char *);
154 static void arpintr(struct netmsg *);
155 static void arptfree (struct llinfo_arp *);
156 static void arptimer (void *);
157 static struct llinfo_arp
158 *arplookup (in_addr_t addr, boolean_t create, boolean_t proxy);
160 static void in_arpinput (struct mbuf *);
163 static struct callout arptimer_ch[MAXCPU];
166 * Timeout routine. Age arp_tab entries periodically.
170 arptimer(void *ignored_arg)
172 struct llinfo_arp *la, *nla;
175 LIST_FOREACH_MUTABLE(la, &llinfo_arp_list[mycpuid], la_le, nla) {
176 if (la->la_rt->rt_expire && la->la_rt->rt_expire <= time_second)
179 callout_reset(&arptimer_ch[mycpuid], arpt_prune * hz, arptimer, NULL);
184 * Parallel to llc_rtrequest.
187 arp_rtrequest(int req, struct rtentry *rt, struct rt_addrinfo *info)
189 struct sockaddr *gate = rt->rt_gateway;
190 struct llinfo_arp *la = rt->rt_llinfo;
192 struct sockaddr_dl null_sdl = { sizeof null_sdl, AF_LINK };
193 static boolean_t arpinit_done[MAXCPU];
195 if (!arpinit_done[mycpuid]) {
196 arpinit_done[mycpuid] = TRUE;
197 callout_init(&arptimer_ch[mycpuid]);
198 callout_reset(&arptimer_ch[mycpuid], hz, arptimer, NULL);
200 if (rt->rt_flags & RTF_GATEWAY)
206 * XXX: If this is a manually added route to interface
207 * such as older version of routed or gated might provide,
208 * restore cloning bit.
210 if (!(rt->rt_flags & RTF_HOST) &&
211 SIN(rt_mask(rt))->sin_addr.s_addr != 0xffffffff)
212 rt->rt_flags |= RTF_CLONING;
213 if (rt->rt_flags & RTF_CLONING) {
215 * Case 1: This route should come from a route to iface.
217 rt_setgate(rt, rt_key(rt),
218 (struct sockaddr *)&null_sdl);
219 gate = rt->rt_gateway;
220 SDL(gate)->sdl_type = rt->rt_ifp->if_type;
221 SDL(gate)->sdl_index = rt->rt_ifp->if_index;
222 rt->rt_expire = time_second;
225 /* Announce a new entry if requested. */
226 if (rt->rt_flags & RTF_ANNOUNCE) {
227 lwkt_serialize_enter(rt->rt_ifp->if_serializer);
228 arprequest(rt->rt_ifp,
229 &SIN(rt_key(rt))->sin_addr,
230 &SIN(rt_key(rt))->sin_addr,
232 lwkt_serialize_exit(rt->rt_ifp->if_serializer);
236 if (gate->sa_family != AF_LINK ||
237 gate->sa_len < sizeof(struct sockaddr_dl)) {
238 log(LOG_DEBUG, "arp_rtrequest: bad gateway value\n");
241 SDL(gate)->sdl_type = rt->rt_ifp->if_type;
242 SDL(gate)->sdl_index = rt->rt_ifp->if_index;
244 break; /* This happens on a route change */
246 * Case 2: This route may come from cloning, or a manual route
247 * add with a LL address.
249 R_Malloc(la, struct llinfo_arp *, sizeof *la);
252 log(LOG_DEBUG, "arp_rtrequest: malloc failed\n");
255 bzero(la, sizeof *la);
257 rt->rt_flags |= RTF_LLINFO;
258 LIST_INSERT_HEAD(&llinfo_arp_list[mycpuid], la, la_le);
262 * This keeps the multicast addresses from showing up
263 * in `arp -a' listings as unresolved. It's not actually
264 * functional. Then the same for broadcast.
266 if (IN_MULTICAST(ntohl(SIN(rt_key(rt))->sin_addr.s_addr))) {
267 ETHER_MAP_IP_MULTICAST(&SIN(rt_key(rt))->sin_addr,
269 SDL(gate)->sdl_alen = 6;
272 if (in_broadcast(SIN(rt_key(rt))->sin_addr, rt->rt_ifp)) {
273 memcpy(LLADDR(SDL(gate)), rt->rt_ifp->if_broadcastaddr,
274 rt->rt_ifp->if_addrlen);
275 SDL(gate)->sdl_alen = rt->rt_ifp->if_addrlen;
280 if (SIN(rt_key(rt))->sin_addr.s_addr ==
281 (IA_SIN(rt->rt_ifa))->sin_addr.s_addr) {
283 * This test used to be
284 * if (loif.if_flags & IFF_UP)
285 * It allowed local traffic to be forced
286 * through the hardware by configuring the
287 * loopback down. However, it causes problems
288 * during network configuration for boards
289 * that can't receive packets they send. It
290 * is now necessary to clear "useloopback" and
291 * remove the route to force traffic out to
295 bcopy(IF_LLADDR(rt->rt_ifp), LLADDR(SDL(gate)),
296 SDL(gate)->sdl_alen = rt->rt_ifp->if_addrlen);
305 LIST_REMOVE(la, la_le);
306 rt->rt_llinfo = NULL;
307 rt->rt_flags &= ~RTF_LLINFO;
308 if (la->la_hold != NULL)
309 m_freem(la->la_hold);
315 * Broadcast an ARP request. Caller specifies:
316 * - arp header source ip address
317 * - arp header target ip address
318 * - arp header source ethernet address
321 arprequest(struct ifnet *ifp, struct in_addr *sip, struct in_addr *tip,
325 struct ether_header *eh;
330 ASSERT_SERIALIZED(ifp->if_serializer);
332 if ((m = m_gethdr(MB_DONTWAIT, MT_DATA)) == NULL)
334 m->m_pkthdr.rcvif = (struct ifnet *)NULL;
336 switch (ifp->if_type) {
339 * This may not be correct for types not explicitly
340 * listed, but this is our best guess
343 ar_hrd = htons(ARPHRD_ETHER);
345 m->m_len = arphdr_len2(ifp->if_addrlen, sizeof(struct in_addr));
346 m->m_pkthdr.len = m->m_len;
347 MH_ALIGN(m, m->m_len);
349 eh = (struct ether_header *)sa.sa_data;
350 /* if_output() will not swap */
351 eh->ether_type = htons(ETHERTYPE_ARP);
352 memcpy(eh->ether_dhost, ifp->if_broadcastaddr, ifp->if_addrlen);
354 ah = mtod(m, struct arphdr *);
359 ah->ar_pro = htons(ETHERTYPE_IP);
360 ah->ar_hln = ifp->if_addrlen; /* hardware address length */
361 ah->ar_pln = sizeof(struct in_addr); /* protocol address length */
362 ah->ar_op = htons(ARPOP_REQUEST);
363 memcpy(ar_sha(ah), enaddr, ah->ar_hln);
364 memset(ar_tha(ah), 0, ah->ar_hln);
365 memcpy(ar_spa(ah), sip, ah->ar_pln);
366 memcpy(ar_tpa(ah), tip, ah->ar_pln);
368 sa.sa_family = AF_UNSPEC;
369 sa.sa_len = sizeof sa;
370 (*ifp->if_output)(ifp, m, &sa, (struct rtentry *)NULL);
374 * Resolve an IP address into an ethernet address. If success,
375 * desten is filled in. If there is no entry in arptab,
376 * set one up and broadcast a request for the IP address.
377 * Hold onto this mbuf and resend it once the address
378 * is finally resolved. A return value of 1 indicates
379 * that desten has been filled in and the packet should be sent
380 * normally; a 0 return indicates that the packet has been
381 * taken over here, either now or for later transmission.
388 struct sockaddr *dst,
392 struct llinfo_arp *la = NULL;
393 struct sockaddr_dl *sdl;
395 if (m->m_flags & M_BCAST) { /* broadcast */
396 memcpy(desten, ifp->if_broadcastaddr, ifp->if_addrlen);
399 if (m->m_flags & M_MCAST) {/* multicast */
400 ETHER_MAP_IP_MULTICAST(&SIN(dst)->sin_addr, desten);
404 if (rt_llroute(dst, rt0, &rt) != 0) {
411 la = arplookup(SIN(dst)->sin_addr.s_addr, TRUE, FALSE);
415 if (la == NULL || rt == NULL) {
416 log(LOG_DEBUG, "arpresolve: can't allocate llinfo for %s%s%s\n",
417 inet_ntoa(SIN(dst)->sin_addr), la ? "la" : " ",
422 sdl = SDL(rt->rt_gateway);
424 * Check the address family and length is valid, the address
425 * is resolved; otherwise, try to resolve.
427 if ((rt->rt_expire == 0 || rt->rt_expire > time_second) &&
428 sdl->sdl_family == AF_LINK && sdl->sdl_alen != 0) {
430 * If entry has an expiry time and it is approaching,
431 * see if we need to send an ARP request within this
432 * arpt_down interval.
434 if ((rt->rt_expire != 0) &&
435 (time_second + la->la_preempt > rt->rt_expire)) {
437 &SIN(rt->rt_ifa->ifa_addr)->sin_addr,
443 bcopy(LLADDR(sdl), desten, sdl->sdl_alen);
447 * If ARP is disabled on this interface, stop.
449 * Probably should not allocate empty llinfo struct if we are
450 * not going to be sending out an arp request.
452 if (ifp->if_flags & IFF_NOARP) {
457 * There is an arptab entry, but no ethernet address
458 * response yet. Replace the held mbuf with this
461 if (la->la_hold != NULL)
462 m_freem(la->la_hold);
464 if (rt->rt_expire || ((rt->rt_flags & RTF_STATIC) && !sdl->sdl_alen)) {
465 rt->rt_flags &= ~RTF_REJECT;
466 if (la->la_asked == 0 || rt->rt_expire != time_second) {
467 rt->rt_expire = time_second;
468 if (la->la_asked++ < arp_maxtries) {
470 &SIN(rt->rt_ifa->ifa_addr)->sin_addr,
474 rt->rt_flags |= RTF_REJECT;
475 rt->rt_expire += arpt_down;
477 la->la_preempt = arp_maxtries;
486 * Common length and type checks are done here,
487 * then the protocol-specific routine is called.
490 arpintr(struct netmsg *msg)
492 struct mbuf *m = ((struct netmsg_packet *)msg)->nm_packet;
496 if (m->m_len < sizeof(struct arphdr) &&
497 ((m = m_pullup(m, sizeof(struct arphdr))) == NULL)) {
498 log(LOG_ERR, "arp: runt packet -- m_pullup failed\n");
501 ar = mtod(m, struct arphdr *);
503 ar_hrd = ntohs(ar->ar_hrd);
504 if (ar_hrd != ARPHRD_ETHER &&
505 ar_hrd != ARPHRD_IEEE802) {
507 "arp: unknown hardware address format (0x%2D)\n",
508 (unsigned char *)&ar->ar_hrd, "");
512 if (m->m_pkthdr.len < arphdr_len(ar) &&
513 (m = m_pullup(m, arphdr_len(ar))) == NULL) {
514 log(LOG_ERR, "arp: runt packet\n");
518 switch (ntohs(ar->ar_pro)) {
529 /* msg was embedded in the mbuf, do not reply! */
534 * ARP for Internet protocols on 10 Mb/s Ethernet.
535 * Algorithm is that given in RFC 826.
536 * In addition, a sanity check is performed on the sender
537 * protocol address, to catch impersonators.
538 * We no longer handle negotiations for use of trailer protocol:
539 * Formerly, ARP replied for protocol type ETHERTYPE_TRAIL sent
540 * along with IP replies if we wanted trailers sent to us,
541 * and also sent them in response to IP replies.
542 * This allowed either end to announce the desire to receive
544 * We no longer reply to requests for ETHERTYPE_TRAIL protocol either,
545 * but formerly didn't normally send requests.
547 static int log_arp_wrong_iface = 1;
548 SYSCTL_INT(_net_link_ether_inet, OID_AUTO, log_arp_wrong_iface, CTLFLAG_RW,
549 &log_arp_wrong_iface, 0,
550 "log arp packets arriving on the wrong interface");
553 arp_update_oncpu(struct mbuf *m, in_addr_t saddr, boolean_t create,
556 struct arphdr *ah = mtod(m, struct arphdr *);
557 struct ifnet *ifp = m->m_pkthdr.rcvif;
558 struct llinfo_arp *la;
559 struct sockaddr_dl *sdl;
563 la = arplookup(saddr, create, FALSE);
564 if (la && (rt = la->la_rt) && (sdl = SDL(rt->rt_gateway))) {
565 struct in_addr isaddr = { saddr };
567 /* the following is not an error when doing bridging */
568 if (rt->rt_ifp != ifp) {
569 if (dologging && log_arp_wrong_iface && cpu == 0) {
572 "but got reply from %*D on %s\n",
574 rt->rt_ifp->if_xname,
575 ifp->if_addrlen, (u_char *)ar_sha(ah), ":",
581 bcmp(ar_sha(ah), LLADDR(sdl), sdl->sdl_alen)) {
582 if (rt->rt_expire != 0) {
583 if (dologging && cpu == 0) {
585 "arp: %s moved from %*D to %*D on %s\n",
587 ifp->if_addrlen, (u_char *)LLADDR(sdl),
588 ":", ifp->if_addrlen,
589 (u_char *)ar_sha(ah), ":",
593 if (dologging && cpu == 0) {
595 "arp: %*D attempts to modify permanent entry for %s on %s\n",
596 ifp->if_addrlen, (u_char *)ar_sha(ah), ":",
597 inet_ntoa(isaddr), ifp->if_xname);
603 * sanity check for the address length.
604 * XXX this does not work for protocols with variable address
607 if (dologging && sdl->sdl_alen && sdl->sdl_alen != ah->ar_hln &&
611 "arp from %*D: new addr len %d, was %d",
612 ifp->if_addrlen, (u_char *) ar_sha(ah), ":",
613 ah->ar_hln, sdl->sdl_alen);
615 if (ifp->if_addrlen != ah->ar_hln) {
616 if (dologging && cpu == 0) {
618 "arp from %*D: addr len: new %d, i/f %d (ignored)",
619 ifp->if_addrlen, (u_char *) ar_sha(ah), ":",
620 ah->ar_hln, ifp->if_addrlen);
624 memcpy(LLADDR(sdl), ar_sha(ah), sdl->sdl_alen = ah->ar_hln);
625 if (rt->rt_expire != 0)
626 rt->rt_expire = time_second + arpt_keep;
627 rt->rt_flags &= ~RTF_REJECT;
629 la->la_preempt = arp_maxtries;
632 * This particular cpu might have been holding an mbuf
633 * pending ARP resolution. If so, transmit the mbuf now.
635 if (la->la_hold != NULL) {
636 m_adj(la->la_hold, sizeof(struct ether_header));
637 lwkt_serialize_enter(ifp->if_serializer);
638 (*ifp->if_output)(ifp, la->la_hold, rt_key(rt), rt);
639 lwkt_serialize_exit(ifp->if_serializer);
647 struct netmsg_arp_update {
648 struct netmsg netmsg;
654 static void arp_update_msghandler(struct netmsg *netmsg);
659 * Called from arpintr() - this routine is run from a single cpu.
662 in_arpinput(struct mbuf *m)
665 struct ifnet *ifp = m->m_pkthdr.rcvif;
666 struct ether_header *eh;
668 struct ifaddr_container *ifac;
669 struct in_ifaddr *ia;
671 struct in_addr isaddr, itaddr, myaddr;
673 struct netmsg_arp_update msg;
675 u_int8_t *enaddr = NULL;
679 req_len = arphdr_len2(ifp->if_addrlen, sizeof(struct in_addr));
680 if (m->m_len < req_len && (m = m_pullup(m, req_len)) == NULL) {
681 log(LOG_ERR, "in_arp: runt packet -- m_pullup failed\n");
685 ah = mtod(m, struct arphdr *);
686 op = ntohs(ah->ar_op);
687 memcpy(&isaddr, ar_spa(ah), sizeof isaddr);
688 memcpy(&itaddr, ar_tpa(ah), sizeof itaddr);
690 * Check both target and sender IP addresses:
692 * If we receive the packet on the interface owning the address,
693 * then accept the address.
695 * For a bridge, we accept the address if the receive interface and
696 * the interface owning the address are on the same bridge.
697 * (This will change slightly when we have clusters of interfaces).
699 LIST_FOREACH(ia, INADDR_HASH(itaddr.s_addr), ia_hash) {
700 /* Skip all ia's which don't match */
701 if (itaddr.s_addr != ia->ia_addr.sin_addr.s_addr)
704 if (ia->ia_ifp == ifp)
707 if (ifp->if_bridge && ia->ia_ifp &&
708 ifp->if_bridge == ia->ia_ifp->if_bridge)
713 * If the interface does not match, but the recieving interface
714 * is part of carp, we call carp_iamatch to see if this is a
715 * request for the virtual host ip.
716 * XXX: This is really ugly!
718 if (ifp->if_carp != NULL &&
719 carp_iamatch(ifp->if_carp, ia, &isaddr, &enaddr) &&
720 itaddr.s_addr == ia->ia_addr.sin_addr.s_addr)
724 LIST_FOREACH(ia, INADDR_HASH(isaddr.s_addr), ia_hash) {
725 /* Skip all ia's which don't match */
726 if (isaddr.s_addr != ia->ia_addr.sin_addr.s_addr)
729 if (ia->ia_ifp == ifp)
732 if (ifp->if_bridge && ia->ia_ifp &&
733 ifp->if_bridge == ia->ia_ifp->if_bridge)
737 * No match, use the first inet address on the receive interface
738 * as a dummy address for the rest of the function.
740 TAILQ_FOREACH(ifac, &ifp->if_addrheads[mycpuid], ifa_link) {
741 struct ifaddr *ifa = ifac->ifa;
743 if (ifa->ifa_addr && ifa->ifa_addr->sa_family == AF_INET) {
749 * If we got here, we didn't find any suitable interface,
750 * so drop the packet.
757 enaddr = (u_int8_t *)IF_LLADDR(ifp);
758 myaddr = ia->ia_addr.sin_addr;
759 if (!bcmp(ar_sha(ah), enaddr, ifp->if_addrlen)) {
760 m_freem(m); /* it's from me, ignore it. */
763 if (!bcmp(ar_sha(ah), ifp->if_broadcastaddr, ifp->if_addrlen)) {
765 "arp: link address is broadcast for IP address %s!\n",
770 if (isaddr.s_addr == myaddr.s_addr && myaddr.s_addr != 0) {
772 "arp: %*D is using my IP address %s!\n",
773 ifp->if_addrlen, (u_char *)ar_sha(ah), ":",
779 netmsg_init(&msg.netmsg, &curthread->td_msgport, 0,
780 arp_update_msghandler);
782 msg.saddr = isaddr.s_addr;
783 msg.create = (itaddr.s_addr == myaddr.s_addr);
784 lwkt_domsg(rtable_portfn(0), &msg.netmsg.nm_lmsg, 0);
786 arp_update_oncpu(m, isaddr.s_addr, (itaddr.s_addr == myaddr.s_addr),
789 if (op != ARPOP_REQUEST) {
793 if (itaddr.s_addr == myaddr.s_addr) {
794 /* I am the target */
795 memcpy(ar_tha(ah), ar_sha(ah), ah->ar_hln);
796 memcpy(ar_sha(ah), enaddr, ah->ar_hln);
798 struct llinfo_arp *la;
800 la = arplookup(itaddr.s_addr, FALSE, SIN_PROXY);
802 struct sockaddr_in sin;
809 bzero(&sin, sizeof sin);
810 sin.sin_family = AF_INET;
811 sin.sin_len = sizeof sin;
812 sin.sin_addr = itaddr;
814 rt = rtpurelookup((struct sockaddr *)&sin);
821 * Don't send proxies for nodes on the same interface
822 * as this one came out of, or we'll get into a fight
823 * over who claims what Ether address.
825 if (rt->rt_ifp == ifp) {
829 memcpy(ar_tha(ah), ar_sha(ah), ah->ar_hln);
830 memcpy(ar_sha(ah), enaddr, ah->ar_hln);
832 kprintf("arp: proxying for %s\n", inet_ntoa(itaddr));
835 struct sockaddr_dl *sdl;
838 memcpy(ar_tha(ah), ar_sha(ah), ah->ar_hln);
839 sdl = SDL(rt->rt_gateway);
840 memcpy(ar_sha(ah), LLADDR(sdl), ah->ar_hln);
844 memcpy(ar_tpa(ah), ar_spa(ah), ah->ar_pln);
845 memcpy(ar_spa(ah), &itaddr, ah->ar_pln);
846 ah->ar_op = htons(ARPOP_REPLY);
847 ah->ar_pro = htons(ETHERTYPE_IP); /* let's be sure! */
848 switch (ifp->if_type) {
851 * May not be correct for types not explictly
852 * listed, but it is our best guess.
855 eh = (struct ether_header *)sa.sa_data;
856 memcpy(eh->ether_dhost, ar_tha(ah), sizeof eh->ether_dhost);
857 eh->ether_type = htons(ETHERTYPE_ARP);
860 sa.sa_family = AF_UNSPEC;
861 sa.sa_len = sizeof sa;
862 lwkt_serialize_enter(ifp->if_serializer);
863 (*ifp->if_output)(ifp, m, &sa, (struct rtentry *)0);
864 lwkt_serialize_exit(ifp->if_serializer);
872 arp_update_msghandler(struct netmsg *netmsg)
874 struct netmsg_arp_update *msg = (struct netmsg_arp_update *)netmsg;
877 arp_update_oncpu(msg->m, msg->saddr, msg->create, FALSE);
879 nextcpu = mycpuid + 1;
880 if (nextcpu < ncpus) {
881 lwkt_forwardmsg(rtable_portfn(nextcpu), &msg->netmsg.nm_lmsg);
883 lwkt_replymsg(&msg->netmsg.nm_lmsg, 0);
892 * Free an arp entry. If the arp entry is actively referenced or represents
893 * a static entry we only clear it back to an unresolved state, otherwise
894 * we destroy the entry entirely.
896 * Note that static entries are created when route add ... -interface is used
897 * to create an interface route to a (direct) destination.
900 arptfree(struct llinfo_arp *la)
902 struct rtentry *rt = la->la_rt;
903 struct sockaddr_dl *sdl;
907 sdl = SDL(rt->rt_gateway);
909 ((rt->rt_refcnt > 0 && sdl->sdl_family == AF_LINK) ||
910 (rt->rt_flags & RTF_STATIC))) {
912 la->la_preempt = la->la_asked = 0;
913 rt->rt_flags &= ~RTF_REJECT;
916 rtrequest(RTM_DELETE, rt_key(rt), NULL, rt_mask(rt), 0, NULL);
920 * Lookup or enter a new address in arptab.
922 static struct llinfo_arp *
923 arplookup(in_addr_t addr, boolean_t create, boolean_t proxy)
926 struct sockaddr_inarp sin = { sizeof sin, AF_INET };
927 const char *why = NULL;
929 sin.sin_addr.s_addr = addr;
930 sin.sin_other = proxy ? SIN_PROXY : 0;
932 rt = rtlookup((struct sockaddr *)&sin);
934 rt = rtpurelookup((struct sockaddr *)&sin);
939 if (rt->rt_flags & RTF_GATEWAY)
940 why = "host is not on local network";
941 else if (!(rt->rt_flags & RTF_LLINFO))
942 why = "could not allocate llinfo";
943 else if (rt->rt_gateway->sa_family != AF_LINK)
944 why = "gateway route is not ours";
948 log(LOG_DEBUG, "arplookup %s failed: %s\n",
949 inet_ntoa(sin.sin_addr), why);
951 if (rt->rt_refcnt <= 0 && (rt->rt_flags & RTF_WASCLONED)) {
952 /* No references to this route. Purge it. */
953 rtrequest(RTM_DELETE, rt_key(rt), rt->rt_gateway,
954 rt_mask(rt), rt->rt_flags, NULL);
958 return (rt->rt_llinfo);
962 arp_ifinit(struct ifnet *ifp, struct ifaddr *ifa)
964 if (IA_SIN(ifa)->sin_addr.s_addr != INADDR_ANY)
965 arprequest(ifp, &IA_SIN(ifa)->sin_addr, &IA_SIN(ifa)->sin_addr,
967 ifa->ifa_rtrequest = arp_rtrequest;
968 ifa->ifa_flags |= RTF_CLONING;
972 arp_ifinit2(struct ifnet *ifp, struct ifaddr *ifa, u_char *enaddr)
974 if (IA_SIN(ifa)->sin_addr.s_addr != INADDR_ANY)
975 arprequest(ifp, &IA_SIN(ifa)->sin_addr, &IA_SIN(ifa)->sin_addr,
977 ifa->ifa_rtrequest = arp_rtrequest;
978 ifa->ifa_flags |= RTF_CLONING;
986 for (cpu = 0; cpu < ncpus2; cpu++)
987 LIST_INIT(&llinfo_arp_list[cpu]);
988 netisr_register(NETISR_ARP, cpu0_portfn, arpintr);
991 SYSINIT(arp, SI_SUB_PROTO_DOMAIN, SI_ORDER_ANY, arp_init, 0);