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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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 1.42 2007/08/27 16:15:42 hasso 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 arprequest(rt->rt_ifp,
228 &SIN(rt_key(rt))->sin_addr,
229 &SIN(rt_key(rt))->sin_addr,
233 if (gate->sa_family != AF_LINK ||
234 gate->sa_len < sizeof(struct sockaddr_dl)) {
235 log(LOG_DEBUG, "arp_rtrequest: bad gateway value\n");
238 SDL(gate)->sdl_type = rt->rt_ifp->if_type;
239 SDL(gate)->sdl_index = rt->rt_ifp->if_index;
241 break; /* This happens on a route change */
243 * Case 2: This route may come from cloning, or a manual route
244 * add with a LL address.
246 R_Malloc(la, struct llinfo_arp *, sizeof *la);
249 log(LOG_DEBUG, "arp_rtrequest: malloc failed\n");
252 bzero(la, sizeof *la);
254 rt->rt_flags |= RTF_LLINFO;
255 LIST_INSERT_HEAD(&llinfo_arp_list[mycpuid], la, la_le);
259 * This keeps the multicast addresses from showing up
260 * in `arp -a' listings as unresolved. It's not actually
261 * functional. Then the same for broadcast.
263 if (IN_MULTICAST(ntohl(SIN(rt_key(rt))->sin_addr.s_addr))) {
264 ETHER_MAP_IP_MULTICAST(&SIN(rt_key(rt))->sin_addr,
266 SDL(gate)->sdl_alen = 6;
269 if (in_broadcast(SIN(rt_key(rt))->sin_addr, rt->rt_ifp)) {
270 memcpy(LLADDR(SDL(gate)), rt->rt_ifp->if_broadcastaddr,
271 rt->rt_ifp->if_addrlen);
272 SDL(gate)->sdl_alen = rt->rt_ifp->if_addrlen;
277 if (SIN(rt_key(rt))->sin_addr.s_addr ==
278 (IA_SIN(rt->rt_ifa))->sin_addr.s_addr) {
280 * This test used to be
281 * if (loif.if_flags & IFF_UP)
282 * It allowed local traffic to be forced
283 * through the hardware by configuring the
284 * loopback down. However, it causes problems
285 * during network configuration for boards
286 * that can't receive packets they send. It
287 * is now necessary to clear "useloopback" and
288 * remove the route to force traffic out to
292 bcopy(IF_LLADDR(rt->rt_ifp), LLADDR(SDL(gate)),
293 SDL(gate)->sdl_alen = rt->rt_ifp->if_addrlen);
302 LIST_REMOVE(la, la_le);
303 rt->rt_llinfo = NULL;
304 rt->rt_flags &= ~RTF_LLINFO;
305 if (la->la_hold != NULL)
306 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,
322 struct ether_header *eh;
325 static u_char llcx[] = { 0x82, 0x40, LLC_SNAP_LSAP, LLC_SNAP_LSAP,
326 LLC_UI, 0x00, 0x00, 0x00, 0x08, 0x06 };
329 if ((m = m_gethdr(MB_DONTWAIT, MT_DATA)) == NULL)
331 m->m_pkthdr.rcvif = (struct ifnet *)NULL;
333 switch (ifp->if_type) {
336 * This may not be correct for types not explicitly
337 * listed, but this is our best guess
340 ar_hrd = htons(ARPHRD_ETHER);
342 m->m_len = arphdr_len2(ifp->if_addrlen, sizeof(struct in_addr));
343 m->m_pkthdr.len = m->m_len;
344 MH_ALIGN(m, m->m_len);
346 eh = (struct ether_header *)sa.sa_data;
347 /* if_output() will not swap */
348 eh->ether_type = htons(ETHERTYPE_ARP);
349 memcpy(eh->ether_dhost, ifp->if_broadcastaddr, ifp->if_addrlen);
351 ah = mtod(m, struct arphdr *);
356 ah->ar_pro = htons(ETHERTYPE_IP);
357 ah->ar_hln = ifp->if_addrlen; /* hardware address length */
358 ah->ar_pln = sizeof(struct in_addr); /* protocol address length */
359 ah->ar_op = htons(ARPOP_REQUEST);
360 memcpy(ar_sha(ah), enaddr, ah->ar_hln);
361 memset(ar_tha(ah), 0, ah->ar_hln);
362 memcpy(ar_spa(ah), sip, ah->ar_pln);
363 memcpy(ar_tpa(ah), tip, ah->ar_pln);
365 sa.sa_family = AF_UNSPEC;
366 sa.sa_len = sizeof sa;
367 (*ifp->if_output)(ifp, m, &sa, (struct rtentry *)NULL);
371 * Resolve an IP address into an ethernet address. If success,
372 * desten is filled in. If there is no entry in arptab,
373 * set one up and broadcast a request for the IP address.
374 * Hold onto this mbuf and resend it once the address
375 * is finally resolved. A return value of 1 indicates
376 * that desten has been filled in and the packet should be sent
377 * normally; a 0 return indicates that the packet has been
378 * taken over here, either now or for later transmission.
385 struct sockaddr *dst,
389 struct llinfo_arp *la = NULL;
390 struct sockaddr_dl *sdl;
392 if (m->m_flags & M_BCAST) { /* broadcast */
393 memcpy(desten, ifp->if_broadcastaddr, ifp->if_addrlen);
396 if (m->m_flags & M_MCAST) {/* multicast */
397 ETHER_MAP_IP_MULTICAST(&SIN(dst)->sin_addr, desten);
401 if (rt_llroute(dst, rt0, &rt) != 0) {
408 la = arplookup(SIN(dst)->sin_addr.s_addr, TRUE, FALSE);
412 if (la == NULL || rt == NULL) {
413 log(LOG_DEBUG, "arpresolve: can't allocate llinfo for %s%s%s\n",
414 inet_ntoa(SIN(dst)->sin_addr), la ? "la" : " ",
419 sdl = SDL(rt->rt_gateway);
421 * Check the address family and length is valid, the address
422 * is resolved; otherwise, try to resolve.
424 if ((rt->rt_expire == 0 || rt->rt_expire > time_second) &&
425 sdl->sdl_family == AF_LINK && sdl->sdl_alen != 0) {
427 * If entry has an expiry time and it is approaching,
428 * see if we need to send an ARP request within this
429 * arpt_down interval.
431 if ((rt->rt_expire != 0) &&
432 (time_second + la->la_preempt > rt->rt_expire)) {
434 &SIN(rt->rt_ifa->ifa_addr)->sin_addr,
440 bcopy(LLADDR(sdl), desten, sdl->sdl_alen);
444 * If ARP is disabled on this interface, stop.
446 * Probably should not allocate empty llinfo struct if we are
447 * not going to be sending out an arp request.
449 if (ifp->if_flags & IFF_NOARP) {
454 * There is an arptab entry, but no ethernet address
455 * response yet. Replace the held mbuf with this
458 if (la->la_hold != NULL)
459 m_freem(la->la_hold);
461 if (rt->rt_expire || ((rt->rt_flags & RTF_STATIC) && !sdl->sdl_alen)) {
462 rt->rt_flags &= ~RTF_REJECT;
463 if (la->la_asked == 0 || rt->rt_expire != time_second) {
464 rt->rt_expire = time_second;
465 if (la->la_asked++ < arp_maxtries) {
467 &SIN(rt->rt_ifa->ifa_addr)->sin_addr,
471 rt->rt_flags |= RTF_REJECT;
472 rt->rt_expire += arpt_down;
474 la->la_preempt = arp_maxtries;
483 * Common length and type checks are done here,
484 * then the protocol-specific routine is called.
487 arpintr(struct netmsg *msg)
489 struct mbuf *m = ((struct netmsg_packet *)msg)->nm_packet;
493 if (m->m_len < sizeof(struct arphdr) &&
494 ((m = m_pullup(m, sizeof(struct arphdr))) == NULL)) {
495 log(LOG_ERR, "arp: runt packet -- m_pullup failed\n");
498 ar = mtod(m, struct arphdr *);
500 ar_hrd = ntohs(ar->ar_hrd);
501 if (ar_hrd != ARPHRD_ETHER &&
502 ar_hrd != ARPHRD_IEEE802) {
504 "arp: unknown hardware address format (0x%2D)\n",
505 (unsigned char *)&ar->ar_hrd, "");
509 if (m->m_pkthdr.len < arphdr_len(ar) &&
510 (m = m_pullup(m, arphdr_len(ar))) == NULL) {
511 log(LOG_ERR, "arp: runt packet\n");
515 switch (ntohs(ar->ar_pro)) {
526 /* msg was embedded in the mbuf, do not reply! */
531 * ARP for Internet protocols on 10 Mb/s Ethernet.
532 * Algorithm is that given in RFC 826.
533 * In addition, a sanity check is performed on the sender
534 * protocol address, to catch impersonators.
535 * We no longer handle negotiations for use of trailer protocol:
536 * Formerly, ARP replied for protocol type ETHERTYPE_TRAIL sent
537 * along with IP replies if we wanted trailers sent to us,
538 * and also sent them in response to IP replies.
539 * This allowed either end to announce the desire to receive
541 * We no longer reply to requests for ETHERTYPE_TRAIL protocol either,
542 * but formerly didn't normally send requests.
544 static int log_arp_wrong_iface = 1;
545 SYSCTL_INT(_net_link_ether_inet, OID_AUTO, log_arp_wrong_iface, CTLFLAG_RW,
546 &log_arp_wrong_iface, 0,
547 "log arp packets arriving on the wrong interface");
550 arp_update_oncpu(struct mbuf *m, in_addr_t saddr, boolean_t create,
553 struct arphdr *ah = mtod(m, struct arphdr *);
554 struct ifnet *ifp = m->m_pkthdr.rcvif;
555 struct llinfo_arp *la;
556 struct sockaddr_dl *sdl;
560 la = arplookup(saddr, create, FALSE);
561 if (la && (rt = la->la_rt) && (sdl = SDL(rt->rt_gateway))) {
562 struct in_addr isaddr = { saddr };
564 /* the following is not an error when doing bridging */
565 if (rt->rt_ifp != ifp) {
566 if (dologging && log_arp_wrong_iface && cpu == 0) {
569 "but got reply from %*D on %s\n",
571 rt->rt_ifp->if_xname,
572 ifp->if_addrlen, (u_char *)ar_sha(ah), ":",
578 bcmp(ar_sha(ah), LLADDR(sdl), sdl->sdl_alen)) {
579 if (rt->rt_expire != 0) {
580 if (dologging && cpu == 0) {
582 "arp: %s moved from %*D to %*D on %s\n",
584 ifp->if_addrlen, (u_char *)LLADDR(sdl),
585 ":", ifp->if_addrlen,
586 (u_char *)ar_sha(ah), ":",
590 if (dologging && cpu == 0) {
592 "arp: %*D attempts to modify permanent entry for %s on %s\n",
593 ifp->if_addrlen, (u_char *)ar_sha(ah), ":",
594 inet_ntoa(isaddr), ifp->if_xname);
600 * sanity check for the address length.
601 * XXX this does not work for protocols with variable address
604 if (dologging && sdl->sdl_alen && sdl->sdl_alen != ah->ar_hln &&
608 "arp from %*D: new addr len %d, was %d",
609 ifp->if_addrlen, (u_char *) ar_sha(ah), ":",
610 ah->ar_hln, sdl->sdl_alen);
612 if (ifp->if_addrlen != ah->ar_hln) {
613 if (dologging && cpu == 0) {
615 "arp from %*D: addr len: new %d, i/f %d (ignored)",
616 ifp->if_addrlen, (u_char *) ar_sha(ah), ":",
617 ah->ar_hln, ifp->if_addrlen);
621 memcpy(LLADDR(sdl), ar_sha(ah), sdl->sdl_alen = ah->ar_hln);
622 if (rt->rt_expire != 0)
623 rt->rt_expire = time_second + arpt_keep;
624 rt->rt_flags &= ~RTF_REJECT;
626 la->la_preempt = arp_maxtries;
629 * This particular cpu might have been holding an mbuf
630 * pending ARP resolution. If so, transmit the mbuf now.
632 if (la->la_hold != NULL) {
633 m_adj(la->la_hold, sizeof(struct ether_header));
634 lwkt_serialize_enter(ifp->if_serializer);
635 (*ifp->if_output)(ifp, la->la_hold, rt_key(rt), rt);
636 lwkt_serialize_exit(ifp->if_serializer);
644 struct netmsg_arp_update {
645 struct netmsg netmsg;
651 static void arp_update_msghandler(struct netmsg *netmsg);
656 * Called from arpintr() - this routine is run from a single cpu.
659 in_arpinput(struct mbuf *m)
662 struct ifnet *ifp = m->m_pkthdr.rcvif;
663 struct ether_header *eh;
666 struct in_ifaddr *ia;
668 struct in_addr isaddr, itaddr, myaddr;
670 struct netmsg_arp_update msg;
672 u_int8_t *enaddr = NULL;
676 req_len = arphdr_len2(ifp->if_addrlen, sizeof(struct in_addr));
677 if (m->m_len < req_len && (m = m_pullup(m, req_len)) == NULL) {
678 log(LOG_ERR, "in_arp: runt packet -- m_pullup failed\n");
682 ah = mtod(m, struct arphdr *);
683 op = ntohs(ah->ar_op);
684 memcpy(&isaddr, ar_spa(ah), sizeof isaddr);
685 memcpy(&itaddr, ar_tpa(ah), sizeof itaddr);
687 * Check both target and sender IP addresses:
689 * If we receive the packet on the interface owning the address,
690 * then accept the address.
692 * For a bridge, we accept the address if the receive interface and
693 * the interface owning the address are on the same bridge.
694 * (This will change slightly when we have clusters of interfaces).
696 LIST_FOREACH(ia, INADDR_HASH(itaddr.s_addr), ia_hash) {
697 /* Skip all ia's which don't match */
698 if (itaddr.s_addr != ia->ia_addr.sin_addr.s_addr)
701 if (ia->ia_ifp == ifp)
704 if (ifp->if_bridge && ia->ia_ifp &&
705 ifp->if_bridge == ia->ia_ifp->if_bridge)
710 * If the interface does not match, but the recieving interface
711 * is part of carp, we call carp_iamatch to see if this is a
712 * request for the virtual host ip.
713 * XXX: This is really ugly!
715 if (ifp->if_carp != NULL &&
716 carp_iamatch(ifp->if_carp, ia, &isaddr, &enaddr) &&
717 itaddr.s_addr == ia->ia_addr.sin_addr.s_addr)
721 LIST_FOREACH(ia, INADDR_HASH(isaddr.s_addr), ia_hash) {
722 /* Skip all ia's which don't match */
723 if (isaddr.s_addr != ia->ia_addr.sin_addr.s_addr)
726 if (ia->ia_ifp == ifp)
729 if (ifp->if_bridge && ia->ia_ifp &&
730 ifp->if_bridge == ia->ia_ifp->if_bridge)
734 * No match, use the first inet address on the receive interface
735 * as a dummy address for the rest of the function.
737 TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) {
738 if (ifa->ifa_addr && ifa->ifa_addr->sa_family == AF_INET) {
744 * If we got here, we didn't find any suitable interface,
745 * so drop the packet.
752 enaddr = (u_int8_t *)IF_LLADDR(ifp);
753 myaddr = ia->ia_addr.sin_addr;
754 if (!bcmp(ar_sha(ah), enaddr, ifp->if_addrlen)) {
755 m_freem(m); /* it's from me, ignore it. */
758 if (!bcmp(ar_sha(ah), ifp->if_broadcastaddr, ifp->if_addrlen)) {
760 "arp: link address is broadcast for IP address %s!\n",
765 if (isaddr.s_addr == myaddr.s_addr && myaddr.s_addr != 0) {
767 "arp: %*D is using my IP address %s!\n",
768 ifp->if_addrlen, (u_char *)ar_sha(ah), ":",
774 netmsg_init(&msg.netmsg, &curthread->td_msgport, 0,
775 arp_update_msghandler);
777 msg.saddr = isaddr.s_addr;
778 msg.create = (itaddr.s_addr == myaddr.s_addr);
779 lwkt_domsg(rtable_portfn(0), &msg.netmsg.nm_lmsg, 0);
781 arp_update_oncpu(m, isaddr.s_addr, (itaddr.s_addr == myaddr.s_addr),
784 if (op != ARPOP_REQUEST) {
788 if (itaddr.s_addr == myaddr.s_addr) {
789 /* I am the target */
790 memcpy(ar_tha(ah), ar_sha(ah), ah->ar_hln);
791 memcpy(ar_sha(ah), enaddr, ah->ar_hln);
793 struct llinfo_arp *la;
795 la = arplookup(itaddr.s_addr, FALSE, SIN_PROXY);
797 struct sockaddr_in sin;
804 bzero(&sin, sizeof sin);
805 sin.sin_family = AF_INET;
806 sin.sin_len = sizeof sin;
807 sin.sin_addr = itaddr;
809 rt = rtpurelookup((struct sockaddr *)&sin);
816 * Don't send proxies for nodes on the same interface
817 * as this one came out of, or we'll get into a fight
818 * over who claims what Ether address.
820 if (rt->rt_ifp == ifp) {
824 memcpy(ar_tha(ah), ar_sha(ah), ah->ar_hln);
825 memcpy(ar_sha(ah), enaddr, ah->ar_hln);
827 kprintf("arp: proxying for %s\n", inet_ntoa(itaddr));
830 struct sockaddr_dl *sdl;
833 memcpy(ar_tha(ah), ar_sha(ah), ah->ar_hln);
834 sdl = SDL(rt->rt_gateway);
835 memcpy(ar_sha(ah), LLADDR(sdl), ah->ar_hln);
839 memcpy(ar_tpa(ah), ar_spa(ah), ah->ar_pln);
840 memcpy(ar_spa(ah), &itaddr, ah->ar_pln);
841 ah->ar_op = htons(ARPOP_REPLY);
842 ah->ar_pro = htons(ETHERTYPE_IP); /* let's be sure! */
843 switch (ifp->if_type) {
846 * May not be correct for types not explictly
847 * listed, but it is our best guess.
850 eh = (struct ether_header *)sa.sa_data;
851 memcpy(eh->ether_dhost, ar_tha(ah), sizeof eh->ether_dhost);
852 eh->ether_type = htons(ETHERTYPE_ARP);
855 sa.sa_family = AF_UNSPEC;
856 sa.sa_len = sizeof sa;
857 lwkt_serialize_enter(ifp->if_serializer);
858 (*ifp->if_output)(ifp, m, &sa, (struct rtentry *)0);
859 lwkt_serialize_exit(ifp->if_serializer);
867 arp_update_msghandler(struct netmsg *netmsg)
869 struct netmsg_arp_update *msg = (struct netmsg_arp_update *)netmsg;
872 arp_update_oncpu(msg->m, msg->saddr, msg->create, FALSE);
874 nextcpu = mycpuid + 1;
875 if (nextcpu < ncpus) {
876 lwkt_forwardmsg(rtable_portfn(nextcpu), &msg->netmsg.nm_lmsg);
878 lwkt_replymsg(&msg->netmsg.nm_lmsg, 0);
887 * Free an arp entry. If the arp entry is actively referenced or represents
888 * a static entry we only clear it back to an unresolved state, otherwise
889 * we destroy the entry entirely.
891 * Note that static entries are created when route add ... -interface is used
892 * to create an interface route to a (direct) destination.
895 arptfree(struct llinfo_arp *la)
897 struct rtentry *rt = la->la_rt;
898 struct sockaddr_dl *sdl;
902 sdl = SDL(rt->rt_gateway);
904 ((rt->rt_refcnt > 0 && sdl->sdl_family == AF_LINK) ||
905 (rt->rt_flags & RTF_STATIC))) {
907 la->la_preempt = la->la_asked = 0;
908 rt->rt_flags &= ~RTF_REJECT;
911 rtrequest(RTM_DELETE, rt_key(rt), NULL, rt_mask(rt), 0, NULL);
915 * Lookup or enter a new address in arptab.
917 static struct llinfo_arp *
918 arplookup(in_addr_t addr, boolean_t create, boolean_t proxy)
921 struct sockaddr_inarp sin = { sizeof sin, AF_INET };
922 const char *why = NULL;
924 sin.sin_addr.s_addr = addr;
925 sin.sin_other = proxy ? SIN_PROXY : 0;
927 rt = rtlookup((struct sockaddr *)&sin);
929 rt = rtpurelookup((struct sockaddr *)&sin);
934 if (rt->rt_flags & RTF_GATEWAY)
935 why = "host is not on local network";
936 else if (!(rt->rt_flags & RTF_LLINFO))
937 why = "could not allocate llinfo";
938 else if (rt->rt_gateway->sa_family != AF_LINK)
939 why = "gateway route is not ours";
943 log(LOG_DEBUG, "arplookup %s failed: %s\n",
944 inet_ntoa(sin.sin_addr), why);
946 if (rt->rt_refcnt <= 0 && (rt->rt_flags & RTF_WASCLONED)) {
947 /* No references to this route. Purge it. */
948 rtrequest(RTM_DELETE, rt_key(rt), rt->rt_gateway,
949 rt_mask(rt), rt->rt_flags, NULL);
953 return (rt->rt_llinfo);
957 arp_ifinit(struct ifnet *ifp, struct ifaddr *ifa)
959 if (IA_SIN(ifa)->sin_addr.s_addr != INADDR_ANY)
960 arprequest(ifp, &IA_SIN(ifa)->sin_addr, &IA_SIN(ifa)->sin_addr,
962 ifa->ifa_rtrequest = arp_rtrequest;
963 ifa->ifa_flags |= RTF_CLONING;
967 arp_ifinit2(struct ifnet *ifp, struct ifaddr *ifa, u_char *enaddr)
969 if (IA_SIN(ifa)->sin_addr.s_addr != INADDR_ANY)
970 arprequest(ifp, &IA_SIN(ifa)->sin_addr, &IA_SIN(ifa)->sin_addr,
972 ifa->ifa_rtrequest = arp_rtrequest;
973 ifa->ifa_flags |= RTF_CLONING;
981 for (cpu = 0; cpu < ncpus2; cpu++)
982 LIST_INIT(&llinfo_arp_list[cpu]);
983 netisr_register(NETISR_ARP, cpu0_portfn, arpintr);
986 SYSINIT(arp, SI_SUB_PROTO_DOMAIN, SI_ORDER_ANY, arp_init, 0);