2 * Copyright (c) 2004, 2005 The DragonFly Project. All rights reserved.
4 * This code is derived from software contributed to The DragonFly Project
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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 1.54 2008/10/01 07:29:16 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>
105 #include <netinet/ip_carp.h>
108 #define SIN(s) ((struct sockaddr_in *)s)
109 #define SDL(s) ((struct sockaddr_dl *)s)
111 SYSCTL_DECL(_net_link_ether);
112 SYSCTL_NODE(_net_link_ether, PF_INET, inet, CTLFLAG_RW, 0, "");
115 static int arpt_prune = (5*60*1); /* walk list every 5 minutes */
116 static int arpt_keep = (20*60); /* once resolved, good for 20 more minutes */
117 static int arpt_down = 20; /* once declared down, don't send for 20 sec */
119 SYSCTL_INT(_net_link_ether_inet, OID_AUTO, prune_intvl, CTLFLAG_RW,
121 SYSCTL_INT(_net_link_ether_inet, OID_AUTO, max_age, CTLFLAG_RW,
123 SYSCTL_INT(_net_link_ether_inet, OID_AUTO, host_down_time, CTLFLAG_RW,
126 #define rt_expire rt_rmx.rmx_expire
129 LIST_ENTRY(llinfo_arp) la_le;
130 struct rtentry *la_rt;
131 struct mbuf *la_hold; /* last packet until resolved/timeout */
132 u_short la_preempt; /* countdown for pre-expiry arps */
133 u_short la_asked; /* #times we QUERIED following expiration */
136 static LIST_HEAD(, llinfo_arp) llinfo_arp_list[MAXCPU];
138 static int arp_maxtries = 5;
139 static int useloopback = 1; /* use loopback interface for local traffic */
140 static int arp_proxyall = 0;
142 SYSCTL_INT(_net_link_ether_inet, OID_AUTO, maxtries, CTLFLAG_RW,
143 &arp_maxtries, 0, "");
144 SYSCTL_INT(_net_link_ether_inet, OID_AUTO, useloopback, CTLFLAG_RW,
145 &useloopback, 0, "");
146 SYSCTL_INT(_net_link_ether_inet, OID_AUTO, proxyall, CTLFLAG_RW,
147 &arp_proxyall, 0, "");
149 static void arp_rtrequest(int, struct rtentry *, struct rt_addrinfo *);
150 static void arprequest(struct ifnet *, struct in_addr *, struct in_addr *,
152 static void arpintr(struct netmsg *);
153 static void arptfree(struct llinfo_arp *);
154 static void arptimer(void *);
155 static struct llinfo_arp *
156 arplookup(in_addr_t, boolean_t, boolean_t);
158 static void in_arpinput(struct mbuf *);
161 static struct callout arptimer_ch[MAXCPU];
164 * Timeout routine. Age arp_tab entries periodically.
168 arptimer(void *ignored_arg)
170 struct llinfo_arp *la, *nla;
173 LIST_FOREACH_MUTABLE(la, &llinfo_arp_list[mycpuid], la_le, nla) {
174 if (la->la_rt->rt_expire && la->la_rt->rt_expire <= time_second)
177 callout_reset(&arptimer_ch[mycpuid], arpt_prune * hz, arptimer, NULL);
182 * Parallel to llc_rtrequest.
185 arp_rtrequest(int req, struct rtentry *rt, struct rt_addrinfo *info)
187 struct sockaddr *gate = rt->rt_gateway;
188 struct llinfo_arp *la = rt->rt_llinfo;
190 struct sockaddr_dl null_sdl = { sizeof null_sdl, AF_LINK };
191 static boolean_t arpinit_done[MAXCPU];
193 if (!arpinit_done[mycpuid]) {
194 arpinit_done[mycpuid] = TRUE;
195 callout_init(&arptimer_ch[mycpuid]);
196 callout_reset(&arptimer_ch[mycpuid], hz, arptimer, NULL);
198 if (rt->rt_flags & RTF_GATEWAY)
204 * XXX: If this is a manually added route to interface
205 * such as older version of routed or gated might provide,
206 * restore cloning bit.
208 if (!(rt->rt_flags & RTF_HOST) &&
209 SIN(rt_mask(rt))->sin_addr.s_addr != 0xffffffff)
210 rt->rt_flags |= RTF_CLONING;
211 if (rt->rt_flags & RTF_CLONING) {
213 * Case 1: This route should come from a route to iface.
215 rt_setgate(rt, rt_key(rt),
216 (struct sockaddr *)&null_sdl);
217 gate = rt->rt_gateway;
218 SDL(gate)->sdl_type = rt->rt_ifp->if_type;
219 SDL(gate)->sdl_index = rt->rt_ifp->if_index;
220 rt->rt_expire = time_second;
223 /* Announce a new entry if requested. */
224 if (rt->rt_flags & RTF_ANNOUNCE) {
225 arprequest(rt->rt_ifp,
226 &SIN(rt_key(rt))->sin_addr,
227 &SIN(rt_key(rt))->sin_addr,
232 if (gate->sa_family != AF_LINK ||
233 gate->sa_len < sizeof(struct sockaddr_dl)) {
234 log(LOG_DEBUG, "arp_rtrequest: bad gateway value\n");
237 SDL(gate)->sdl_type = rt->rt_ifp->if_type;
238 SDL(gate)->sdl_index = rt->rt_ifp->if_index;
240 break; /* This happens on a route change */
242 * Case 2: This route may come from cloning, or a manual route
243 * add with a LL address.
245 R_Malloc(la, struct llinfo_arp *, sizeof *la);
248 log(LOG_DEBUG, "arp_rtrequest: malloc failed\n");
251 bzero(la, sizeof *la);
253 rt->rt_flags |= RTF_LLINFO;
254 LIST_INSERT_HEAD(&llinfo_arp_list[mycpuid], la, la_le);
258 * This keeps the multicast addresses from showing up
259 * in `arp -a' listings as unresolved. It's not actually
260 * functional. Then the same for broadcast.
262 if (IN_MULTICAST(ntohl(SIN(rt_key(rt))->sin_addr.s_addr))) {
263 ETHER_MAP_IP_MULTICAST(&SIN(rt_key(rt))->sin_addr,
265 SDL(gate)->sdl_alen = 6;
268 if (in_broadcast(SIN(rt_key(rt))->sin_addr, rt->rt_ifp)) {
269 memcpy(LLADDR(SDL(gate)), rt->rt_ifp->if_broadcastaddr,
270 rt->rt_ifp->if_addrlen);
271 SDL(gate)->sdl_alen = rt->rt_ifp->if_addrlen;
276 if (SIN(rt_key(rt))->sin_addr.s_addr ==
277 (IA_SIN(rt->rt_ifa))->sin_addr.s_addr) {
279 * This test used to be
280 * if (loif.if_flags & IFF_UP)
281 * It allowed local traffic to be forced
282 * through the hardware by configuring the
283 * loopback down. However, it causes problems
284 * during network configuration for boards
285 * that can't receive packets they send. It
286 * is now necessary to clear "useloopback" and
287 * remove the route to force traffic out to
291 bcopy(IF_LLADDR(rt->rt_ifp), LLADDR(SDL(gate)),
292 SDL(gate)->sdl_alen = rt->rt_ifp->if_addrlen);
301 LIST_REMOVE(la, la_le);
302 rt->rt_llinfo = NULL;
303 rt->rt_flags &= ~RTF_LLINFO;
304 if (la->la_hold != NULL)
305 m_freem(la->la_hold);
312 * Broadcast an ARP request. Caller specifies:
313 * - arp header source ip address
314 * - arp header target ip address
315 * - arp header source ethernet address
318 arprequest(struct ifnet *ifp, struct in_addr *sip, struct in_addr *tip,
319 const u_char *enaddr)
322 struct ether_header *eh;
327 if ((m = m_gethdr(MB_DONTWAIT, MT_DATA)) == NULL)
329 m->m_pkthdr.rcvif = NULL;
331 switch (ifp->if_type) {
334 * This may not be correct for types not explicitly
335 * listed, but this is our best guess
338 ar_hrd = htons(ARPHRD_ETHER);
340 m->m_len = arphdr_len2(ifp->if_addrlen, sizeof(struct in_addr));
341 m->m_pkthdr.len = m->m_len;
342 MH_ALIGN(m, m->m_len);
344 eh = (struct ether_header *)sa.sa_data;
345 /* if_output() will not swap */
346 eh->ether_type = htons(ETHERTYPE_ARP);
347 memcpy(eh->ether_dhost, ifp->if_broadcastaddr, ifp->if_addrlen);
349 ah = mtod(m, struct arphdr *);
354 ah->ar_pro = htons(ETHERTYPE_IP);
355 ah->ar_hln = ifp->if_addrlen; /* hardware address length */
356 ah->ar_pln = sizeof(struct in_addr); /* protocol address length */
357 ah->ar_op = htons(ARPOP_REQUEST);
358 memcpy(ar_sha(ah), enaddr, ah->ar_hln);
359 memset(ar_tha(ah), 0, ah->ar_hln);
360 memcpy(ar_spa(ah), sip, ah->ar_pln);
361 memcpy(ar_tpa(ah), tip, ah->ar_pln);
363 sa.sa_family = AF_UNSPEC;
364 sa.sa_len = sizeof sa;
365 ifp->if_output(ifp, m, &sa, NULL);
369 * Resolve an IP address into an ethernet address. If success,
370 * desten is filled in. If there is no entry in arptab,
371 * set one up and broadcast a request for the IP address.
372 * Hold onto this mbuf and resend it once the address
373 * is finally resolved. A return value of 1 indicates
374 * that desten has been filled in and the packet should be sent
375 * normally; a 0 return indicates that the packet has been
376 * taken over here, either now or for later transmission.
379 arpresolve(struct ifnet *ifp, struct rtentry *rt0, struct mbuf *m,
380 struct sockaddr *dst, u_char *desten)
383 struct llinfo_arp *la = NULL;
384 struct sockaddr_dl *sdl;
386 if (m->m_flags & M_BCAST) { /* broadcast */
387 memcpy(desten, ifp->if_broadcastaddr, ifp->if_addrlen);
390 if (m->m_flags & M_MCAST) {/* multicast */
391 ETHER_MAP_IP_MULTICAST(&SIN(dst)->sin_addr, desten);
395 if (rt_llroute(dst, rt0, &rt) != 0) {
402 la = arplookup(SIN(dst)->sin_addr.s_addr, TRUE, FALSE);
406 if (la == NULL || rt == NULL) {
407 log(LOG_DEBUG, "arpresolve: can't allocate llinfo for %s%s%s\n",
408 inet_ntoa(SIN(dst)->sin_addr), la ? "la" : " ",
413 sdl = SDL(rt->rt_gateway);
415 * Check the address family and length is valid, the address
416 * is resolved; otherwise, try to resolve.
418 if ((rt->rt_expire == 0 || rt->rt_expire > time_second) &&
419 sdl->sdl_family == AF_LINK && sdl->sdl_alen != 0) {
421 * If entry has an expiry time and it is approaching,
422 * see if we need to send an ARP request within this
423 * arpt_down interval.
425 if ((rt->rt_expire != 0) &&
426 (time_second + la->la_preempt > rt->rt_expire)) {
428 &SIN(rt->rt_ifa->ifa_addr)->sin_addr,
434 bcopy(LLADDR(sdl), desten, sdl->sdl_alen);
438 * If ARP is disabled on this interface, stop.
440 * Probably should not allocate empty llinfo struct if we are
441 * not going to be sending out an arp request.
443 if (ifp->if_flags & IFF_NOARP) {
448 * There is an arptab entry, but no ethernet address
449 * response yet. Replace the held mbuf with this
452 if (la->la_hold != NULL)
453 m_freem(la->la_hold);
455 if (rt->rt_expire || ((rt->rt_flags & RTF_STATIC) && !sdl->sdl_alen)) {
456 rt->rt_flags &= ~RTF_REJECT;
457 if (la->la_asked == 0 || rt->rt_expire != time_second) {
458 rt->rt_expire = time_second;
459 if (la->la_asked++ < arp_maxtries) {
461 &SIN(rt->rt_ifa->ifa_addr)->sin_addr,
465 rt->rt_flags |= RTF_REJECT;
466 rt->rt_expire += arpt_down;
468 la->la_preempt = arp_maxtries;
476 * Common length and type checks are done here,
477 * then the protocol-specific routine is called.
480 arpintr(struct netmsg *msg)
482 struct mbuf *m = ((struct netmsg_packet *)msg)->nm_packet;
486 if (m->m_len < sizeof(struct arphdr) &&
487 (m = m_pullup(m, sizeof(struct arphdr))) == NULL) {
488 log(LOG_ERR, "arp: runt packet -- m_pullup failed\n");
491 ar = mtod(m, struct arphdr *);
493 ar_hrd = ntohs(ar->ar_hrd);
494 if (ar_hrd != ARPHRD_ETHER && ar_hrd != ARPHRD_IEEE802) {
495 log(LOG_ERR, "arp: unknown hardware address format (0x%2D)\n",
496 (unsigned char *)&ar->ar_hrd, "");
501 if (m->m_pkthdr.len < arphdr_len(ar)) {
502 if ((m = m_pullup(m, arphdr_len(ar))) == NULL) {
503 log(LOG_ERR, "arp: runt packet\n");
506 ar = mtod(m, struct arphdr *);
509 switch (ntohs(ar->ar_pro)) {
517 /* msg was embedded in the mbuf, do not reply! */
522 * ARP for Internet protocols on 10 Mb/s Ethernet.
523 * Algorithm is that given in RFC 826.
524 * In addition, a sanity check is performed on the sender
525 * protocol address, to catch impersonators.
526 * We no longer handle negotiations for use of trailer protocol:
527 * Formerly, ARP replied for protocol type ETHERTYPE_TRAIL sent
528 * along with IP replies if we wanted trailers sent to us,
529 * and also sent them in response to IP replies.
530 * This allowed either end to announce the desire to receive
532 * We no longer reply to requests for ETHERTYPE_TRAIL protocol either,
533 * but formerly didn't normally send requests.
535 static int log_arp_wrong_iface = 1;
536 SYSCTL_INT(_net_link_ether_inet, OID_AUTO, log_arp_wrong_iface, CTLFLAG_RW,
537 &log_arp_wrong_iface, 0,
538 "log arp packets arriving on the wrong interface");
541 arp_update_oncpu(struct mbuf *m, in_addr_t saddr, boolean_t create,
544 struct arphdr *ah = mtod(m, struct arphdr *);
545 struct ifnet *ifp = m->m_pkthdr.rcvif;
546 struct llinfo_arp *la;
547 struct sockaddr_dl *sdl;
550 la = arplookup(saddr, create, FALSE);
551 if (la && (rt = la->la_rt) && (sdl = SDL(rt->rt_gateway))) {
552 struct in_addr isaddr = { saddr };
554 /* the following is not an error when doing bridging */
555 if (rt->rt_ifp != ifp) {
556 if (dologging && log_arp_wrong_iface) {
559 "but got reply from %*D on %s\n",
561 rt->rt_ifp->if_xname,
562 ifp->if_addrlen, (u_char *)ar_sha(ah), ":",
568 bcmp(ar_sha(ah), LLADDR(sdl), sdl->sdl_alen)) {
569 if (rt->rt_expire != 0) {
572 "arp: %s moved from %*D to %*D on %s\n",
574 ifp->if_addrlen, (u_char *)LLADDR(sdl),
575 ":", ifp->if_addrlen,
576 (u_char *)ar_sha(ah), ":",
582 "arp: %*D attempts to modify "
583 "permanent entry for %s on %s\n",
584 ifp->if_addrlen, (u_char *)ar_sha(ah),
585 ":", inet_ntoa(isaddr), ifp->if_xname);
591 * sanity check for the address length.
592 * XXX this does not work for protocols with variable address
595 if (dologging && sdl->sdl_alen && sdl->sdl_alen != ah->ar_hln) {
597 "arp from %*D: new addr len %d, was %d",
598 ifp->if_addrlen, (u_char *) ar_sha(ah), ":",
599 ah->ar_hln, sdl->sdl_alen);
601 if (ifp->if_addrlen != ah->ar_hln) {
604 "arp from %*D: addr len: new %d, i/f %d "
606 ifp->if_addrlen, (u_char *) ar_sha(ah), ":",
607 ah->ar_hln, ifp->if_addrlen);
611 memcpy(LLADDR(sdl), ar_sha(ah), sdl->sdl_alen = ah->ar_hln);
612 if (rt->rt_expire != 0)
613 rt->rt_expire = time_second + arpt_keep;
614 rt->rt_flags &= ~RTF_REJECT;
616 la->la_preempt = arp_maxtries;
619 * This particular cpu might have been holding an mbuf
620 * pending ARP resolution. If so, transmit the mbuf now.
622 if (la->la_hold != NULL) {
623 m_adj(la->la_hold, sizeof(struct ether_header));
624 ifp->if_output(ifp, la->la_hold, rt_key(rt), rt);
632 struct netmsg_arp_update {
633 struct netmsg netmsg;
639 static void arp_update_msghandler(struct netmsg *);
644 * Called from arpintr() - this routine is run from a single cpu.
647 in_arpinput(struct mbuf *m)
650 struct ifnet *ifp = m->m_pkthdr.rcvif;
651 struct ether_header *eh;
653 struct ifaddr_container *ifac;
654 struct in_ifaddr_container *iac;
655 struct in_ifaddr *ia;
657 struct in_addr isaddr, itaddr, myaddr;
659 struct netmsg_arp_update msg;
661 u_int8_t *enaddr = NULL;
665 req_len = arphdr_len2(ifp->if_addrlen, sizeof(struct in_addr));
666 if (m->m_len < req_len && (m = m_pullup(m, req_len)) == NULL) {
667 log(LOG_ERR, "in_arp: runt packet -- m_pullup failed\n");
671 ah = mtod(m, struct arphdr *);
672 op = ntohs(ah->ar_op);
673 memcpy(&isaddr, ar_spa(ah), sizeof isaddr);
674 memcpy(&itaddr, ar_tpa(ah), sizeof itaddr);
676 * Check both target and sender IP addresses:
678 * If we receive the packet on the interface owning the address,
679 * then accept the address.
681 * For a bridge, we accept the address if the receive interface and
682 * the interface owning the address are on the same bridge.
683 * (This will change slightly when we have clusters of interfaces).
685 LIST_FOREACH(iac, INADDR_HASH(itaddr.s_addr), ia_hash) {
688 /* Skip all ia's which don't match */
689 if (itaddr.s_addr != ia->ia_addr.sin_addr.s_addr)
692 if (ia->ia_ifp == ifp)
695 if (ifp->if_bridge && ia->ia_ifp &&
696 ifp->if_bridge == ia->ia_ifp->if_bridge)
701 * If the interface does not match, but the recieving interface
702 * is part of carp, we call carp_iamatch to see if this is a
703 * request for the virtual host ip.
704 * XXX: This is really ugly!
706 if (ifp->if_carp != NULL &&
707 carp_iamatch(ifp->if_carp, ia, &isaddr, &enaddr) &&
708 itaddr.s_addr == ia->ia_addr.sin_addr.s_addr)
712 LIST_FOREACH(iac, INADDR_HASH(isaddr.s_addr), ia_hash) {
715 /* Skip all ia's which don't match */
716 if (isaddr.s_addr != ia->ia_addr.sin_addr.s_addr)
719 if (ia->ia_ifp == ifp)
722 if (ifp->if_bridge && ia->ia_ifp &&
723 ifp->if_bridge == ia->ia_ifp->if_bridge)
727 * No match, use the first inet address on the receive interface
728 * as a dummy address for the rest of the function.
730 TAILQ_FOREACH(ifac, &ifp->if_addrheads[mycpuid], ifa_link) {
731 struct ifaddr *ifa = ifac->ifa;
733 if (ifa->ifa_addr && ifa->ifa_addr->sa_family == AF_INET) {
739 * If we got here, we didn't find any suitable interface,
740 * so drop the packet.
747 enaddr = (u_int8_t *)IF_LLADDR(ifp);
748 myaddr = ia->ia_addr.sin_addr;
749 if (!bcmp(ar_sha(ah), enaddr, ifp->if_addrlen)) {
750 m_freem(m); /* it's from me, ignore it. */
753 if (!bcmp(ar_sha(ah), ifp->if_broadcastaddr, ifp->if_addrlen)) {
755 "arp: link address is broadcast for IP address %s!\n",
760 if (isaddr.s_addr == myaddr.s_addr && myaddr.s_addr != 0) {
762 "arp: %*D is using my IP address %s!\n",
763 ifp->if_addrlen, (u_char *)ar_sha(ah), ":",
769 netmsg_init(&msg.netmsg, &curthread->td_msgport, 0,
770 arp_update_msghandler);
772 msg.saddr = isaddr.s_addr;
773 msg.create = (itaddr.s_addr == myaddr.s_addr);
774 lwkt_domsg(rtable_portfn(0), &msg.netmsg.nm_lmsg, 0);
776 arp_update_oncpu(m, isaddr.s_addr, (itaddr.s_addr == myaddr.s_addr),
780 if (op != ARPOP_REQUEST) {
784 if (itaddr.s_addr == myaddr.s_addr) {
785 /* I am the target */
786 memcpy(ar_tha(ah), ar_sha(ah), ah->ar_hln);
787 memcpy(ar_sha(ah), enaddr, ah->ar_hln);
789 struct llinfo_arp *la;
791 la = arplookup(itaddr.s_addr, FALSE, SIN_PROXY);
793 struct sockaddr_in sin;
800 bzero(&sin, sizeof sin);
801 sin.sin_family = AF_INET;
802 sin.sin_len = sizeof sin;
803 sin.sin_addr = itaddr;
805 rt = rtpurelookup((struct sockaddr *)&sin);
812 * Don't send proxies for nodes on the same interface
813 * as this one came out of, or we'll get into a fight
814 * over who claims what Ether address.
816 if (rt->rt_ifp == ifp) {
820 memcpy(ar_tha(ah), ar_sha(ah), ah->ar_hln);
821 memcpy(ar_sha(ah), enaddr, ah->ar_hln);
823 kprintf("arp: proxying for %s\n", inet_ntoa(itaddr));
826 struct sockaddr_dl *sdl;
829 memcpy(ar_tha(ah), ar_sha(ah), ah->ar_hln);
830 sdl = SDL(rt->rt_gateway);
831 memcpy(ar_sha(ah), LLADDR(sdl), ah->ar_hln);
835 memcpy(ar_tpa(ah), ar_spa(ah), ah->ar_pln);
836 memcpy(ar_spa(ah), &itaddr, ah->ar_pln);
837 ah->ar_op = htons(ARPOP_REPLY);
838 ah->ar_pro = htons(ETHERTYPE_IP); /* let's be sure! */
839 switch (ifp->if_type) {
842 * May not be correct for types not explictly
843 * listed, but it is our best guess.
846 eh = (struct ether_header *)sa.sa_data;
847 memcpy(eh->ether_dhost, ar_tha(ah), sizeof eh->ether_dhost);
848 eh->ether_type = htons(ETHERTYPE_ARP);
851 sa.sa_family = AF_UNSPEC;
852 sa.sa_len = sizeof sa;
853 ifp->if_output(ifp, m, &sa, NULL);
859 arp_update_msghandler(struct netmsg *netmsg)
861 struct netmsg_arp_update *msg = (struct netmsg_arp_update *)netmsg;
864 arp_update_oncpu(msg->m, msg->saddr, msg->create, mycpuid == 0);
866 nextcpu = mycpuid + 1;
868 lwkt_forwardmsg(rtable_portfn(nextcpu), &msg->netmsg.nm_lmsg);
870 lwkt_replymsg(&msg->netmsg.nm_lmsg, 0);
878 * Free an arp entry. If the arp entry is actively referenced or represents
879 * a static entry we only clear it back to an unresolved state, otherwise
880 * we destroy the entry entirely.
882 * Note that static entries are created when route add ... -interface is used
883 * to create an interface route to a (direct) destination.
886 arptfree(struct llinfo_arp *la)
888 struct rtentry *rt = la->la_rt;
889 struct sockaddr_dl *sdl;
893 sdl = SDL(rt->rt_gateway);
895 ((rt->rt_refcnt > 0 && sdl->sdl_family == AF_LINK) ||
896 (rt->rt_flags & RTF_STATIC))) {
898 la->la_preempt = la->la_asked = 0;
899 rt->rt_flags &= ~RTF_REJECT;
902 rtrequest(RTM_DELETE, rt_key(rt), NULL, rt_mask(rt), 0, NULL);
906 * Lookup or enter a new address in arptab.
908 static struct llinfo_arp *
909 arplookup(in_addr_t addr, boolean_t create, boolean_t proxy)
912 struct sockaddr_inarp sin = { sizeof sin, AF_INET };
913 const char *why = NULL;
915 sin.sin_addr.s_addr = addr;
916 sin.sin_other = proxy ? SIN_PROXY : 0;
918 rt = rtlookup((struct sockaddr *)&sin);
920 rt = rtpurelookup((struct sockaddr *)&sin);
925 if (rt->rt_flags & RTF_GATEWAY)
926 why = "host is not on local network";
927 else if (!(rt->rt_flags & RTF_LLINFO))
928 why = "could not allocate llinfo";
929 else if (rt->rt_gateway->sa_family != AF_LINK)
930 why = "gateway route is not ours";
934 log(LOG_DEBUG, "arplookup %s failed: %s\n",
935 inet_ntoa(sin.sin_addr), why);
937 if (rt->rt_refcnt <= 0 && (rt->rt_flags & RTF_WASCLONED)) {
938 /* No references to this route. Purge it. */
939 rtrequest(RTM_DELETE, rt_key(rt), rt->rt_gateway,
940 rt_mask(rt), rt->rt_flags, NULL);
944 return (rt->rt_llinfo);
948 arp_ifinit(struct ifnet *ifp, struct ifaddr *ifa)
950 ASSERT_SERIALIZED(ifp->if_serializer);
952 if (IA_SIN(ifa)->sin_addr.s_addr != INADDR_ANY) {
953 lwkt_serialize_exit(ifp->if_serializer);
954 arprequest(ifp, &IA_SIN(ifa)->sin_addr, &IA_SIN(ifa)->sin_addr,
956 lwkt_serialize_enter(ifp->if_serializer);
958 ifa->ifa_rtrequest = arp_rtrequest;
959 ifa->ifa_flags |= RTF_CLONING;
963 arp_ifinit2(struct ifnet *ifp, struct ifaddr *ifa, u_char *enaddr)
965 ASSERT_NOT_SERIALIZED(ifp->if_serializer);
967 if (IA_SIN(ifa)->sin_addr.s_addr != INADDR_ANY)
968 arprequest(ifp, &IA_SIN(ifa)->sin_addr, &IA_SIN(ifa)->sin_addr,
970 ifa->ifa_rtrequest = arp_rtrequest;
971 ifa->ifa_flags |= RTF_CLONING;
979 for (cpu = 0; cpu < ncpus2; cpu++)
980 LIST_INIT(&llinfo_arp_list[cpu]);
981 netisr_register(NETISR_ARP, cpu0_portfn, arpintr,
982 NETISR_FLAG_NOTMPSAFE);
985 SYSINIT(arp, SI_SUB_PROTO_DOMAIN, SI_ORDER_ANY, arp_init, 0);