2 * Copyright (c) 1982, 1986, 1988, 1993
3 * The Regents of the University of California. All rights reserved.
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6 * modification, are permitted provided that the following conditions
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9 * notice, this list of conditions and the following disclaimer.
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13 * 3. All advertising materials mentioning features or use of this software
14 * must display the following acknowledgement:
15 * This product includes software developed by the University of
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33 * @(#)if_ether.c 8.1 (Berkeley) 6/10/93
34 * $FreeBSD: src/sys/netinet/if_ether.c,v 1.64.2.23 2003/04/11 07:23:15 fjoe Exp $
35 * $DragonFly: src/sys/netinet/if_ether.c,v 1.14 2004/07/17 09:43:05 joerg Exp $
39 * Ethernet address resolution protocol.
41 * add "inuse/lock" bit (or ref. count) along with valid bit
47 #include <sys/param.h>
48 #include <sys/kernel.h>
49 #include <sys/queue.h>
50 #include <sys/sysctl.h>
51 #include <sys/systm.h>
53 #include <sys/malloc.h>
54 #include <sys/socket.h>
55 #include <sys/syslog.h>
57 #include <sys/thread2.h>
58 #include <sys/msgport2.h>
61 #include <net/if_dl.h>
62 #include <net/if_types.h>
63 #include <net/route.h>
64 #include <net/netisr.h>
65 #include <net/if_llc.h>
67 #include <net/ethernet.h>
68 #include <net/bridge/bridge.h>
71 #include <netinet/in.h>
72 #include <netinet/in_var.h>
73 #include <netinet/if_ether.h>
75 #include <net/if_arc.h>
76 #include <net/iso88025.h>
78 #define SIN(s) ((struct sockaddr_in *)s)
79 #define SDL(s) ((struct sockaddr_dl *)s)
81 SYSCTL_DECL(_net_link_ether);
82 SYSCTL_NODE(_net_link_ether, PF_INET, inet, CTLFLAG_RW, 0, "");
85 static int arpt_prune = (5*60*1); /* walk list every 5 minutes */
86 static int arpt_keep = (20*60); /* once resolved, good for 20 more minutes */
87 static int arpt_down = 20; /* once declared down, don't send for 20 sec */
89 SYSCTL_INT(_net_link_ether_inet, OID_AUTO, prune_intvl, CTLFLAG_RW,
91 SYSCTL_INT(_net_link_ether_inet, OID_AUTO, max_age, CTLFLAG_RW,
93 SYSCTL_INT(_net_link_ether_inet, OID_AUTO, host_down_time, CTLFLAG_RW,
96 #define rt_expire rt_rmx.rmx_expire
99 LIST_ENTRY(llinfo_arp) la_le;
100 struct rtentry *la_rt;
101 struct mbuf *la_hold; /* last packet until resolved/timeout */
102 u_short la_preempt; /* #times we QUERIED before entry expiration */
103 u_short la_asked; /* #times we QUERIED following expiration */
104 #define la_timer la_rt->rt_rmx.rmx_expire /* deletion time in seconds */
107 static LIST_HEAD(, llinfo_arp) llinfo_arp;
109 static int arp_inuse, arp_allocated, arpinit_done;
111 static int arp_maxtries = 5;
112 static int useloopback = 1; /* use loopback interface for local traffic */
113 static int arp_proxyall = 0;
115 SYSCTL_INT(_net_link_ether_inet, OID_AUTO, maxtries, CTLFLAG_RW,
116 &arp_maxtries, 0, "");
117 SYSCTL_INT(_net_link_ether_inet, OID_AUTO, useloopback, CTLFLAG_RW,
118 &useloopback, 0, "");
119 SYSCTL_INT(_net_link_ether_inet, OID_AUTO, proxyall, CTLFLAG_RW,
120 &arp_proxyall, 0, "");
122 static void arp_rtrequest (int, struct rtentry *, struct rt_addrinfo *);
123 static void arprequest (struct ifnet *,
124 struct in_addr *, struct in_addr *, u_char *);
125 static int arpintr(struct netmsg *);
126 static void arptfree (struct llinfo_arp *);
127 static void arptimer (void *);
128 static struct llinfo_arp
129 *arplookup (u_long, int, int);
131 static void in_arpinput (struct mbuf *);
135 * Timeout routine. Age arp_tab entries periodically.
139 arptimer(ignored_arg)
143 struct llinfo_arp *la = LIST_FIRST(&llinfo_arp);
144 struct llinfo_arp *ola;
146 timeout(arptimer, (caddr_t)0, arpt_prune * hz);
147 while ((ola = la) != 0) {
148 struct rtentry *rt = la->la_rt;
149 la = LIST_NEXT(la, la_le);
150 if (rt->rt_expire && rt->rt_expire <= time_second)
151 arptfree(ola); /* timer has expired, clear */
157 * Parallel to llc_rtrequest.
160 arp_rtrequest(req, rt, info)
163 struct rt_addrinfo *info;
165 struct sockaddr *gate = rt->rt_gateway;
166 struct llinfo_arp *la = (struct llinfo_arp *)rt->rt_llinfo;
167 static struct sockaddr_dl null_sdl = {sizeof(null_sdl), AF_LINK};
171 timeout(arptimer, (caddr_t)0, hz);
173 if (rt->rt_flags & RTF_GATEWAY)
179 * XXX: If this is a manually added route to interface
180 * such as older version of routed or gated might provide,
181 * restore cloning bit.
183 if ((rt->rt_flags & RTF_HOST) == 0 &&
184 SIN(rt_mask(rt))->sin_addr.s_addr != 0xffffffff)
185 rt->rt_flags |= RTF_CLONING;
186 if (rt->rt_flags & RTF_CLONING) {
188 * Case 1: This route should come from a route to iface.
190 rt_setgate(rt, rt_key(rt),
191 (struct sockaddr *)&null_sdl);
192 gate = rt->rt_gateway;
193 SDL(gate)->sdl_type = rt->rt_ifp->if_type;
194 SDL(gate)->sdl_index = rt->rt_ifp->if_index;
195 rt->rt_expire = time_second;
198 /* Announce a new entry if requested. */
199 if (rt->rt_flags & RTF_ANNOUNCE)
200 arprequest(rt->rt_ifp,
201 &SIN(rt_key(rt))->sin_addr,
202 &SIN(rt_key(rt))->sin_addr,
203 (u_char *)LLADDR(SDL(gate)));
206 if (gate->sa_family != AF_LINK ||
207 gate->sa_len < sizeof(null_sdl)) {
208 log(LOG_DEBUG, "arp_rtrequest: bad gateway value\n");
211 SDL(gate)->sdl_type = rt->rt_ifp->if_type;
212 SDL(gate)->sdl_index = rt->rt_ifp->if_index;
214 break; /* This happens on a route change */
216 * Case 2: This route may come from cloning, or a manual route
217 * add with a LL address.
219 R_Malloc(la, struct llinfo_arp *, sizeof(*la));
220 rt->rt_llinfo = (caddr_t)la;
222 log(LOG_DEBUG, "arp_rtrequest: malloc failed\n");
225 arp_inuse++, arp_allocated++;
226 Bzero(la, sizeof(*la));
228 rt->rt_flags |= RTF_LLINFO;
229 LIST_INSERT_HEAD(&llinfo_arp, la, la_le);
233 * This keeps the multicast addresses from showing up
234 * in `arp -a' listings as unresolved. It's not actually
235 * functional. Then the same for broadcast.
237 if (IN_MULTICAST(ntohl(SIN(rt_key(rt))->sin_addr.s_addr))
238 && rt->rt_ifp->if_type != IFT_ARCNET) {
239 ETHER_MAP_IP_MULTICAST(&SIN(rt_key(rt))->sin_addr,
241 SDL(gate)->sdl_alen = 6;
244 if (in_broadcast(SIN(rt_key(rt))->sin_addr, rt->rt_ifp)) {
245 memcpy(LLADDR(SDL(gate)), rt->rt_ifp->if_broadcastaddr,
246 rt->rt_ifp->if_addrlen);
247 SDL(gate)->sdl_alen = rt->rt_ifp->if_addrlen;
252 if (SIN(rt_key(rt))->sin_addr.s_addr ==
253 (IA_SIN(rt->rt_ifa))->sin_addr.s_addr) {
255 * This test used to be
256 * if (loif.if_flags & IFF_UP)
257 * It allowed local traffic to be forced
258 * through the hardware by configuring the loopback down.
259 * However, it causes problems during network configuration
260 * for boards that can't receive packets they send.
261 * It is now necessary to clear "useloopback" and remove
262 * the route to force traffic out to the hardware.
265 Bcopy(IF_LLADDR(rt->rt_ifp), LLADDR(SDL(gate)),
266 SDL(gate)->sdl_alen = rt->rt_ifp->if_addrlen);
277 LIST_REMOVE(la, la_le);
279 rt->rt_flags &= ~RTF_LLINFO;
281 m_freem(la->la_hold);
287 * Broadcast an ARP request. Caller specifies:
288 * - arp header source ip address
289 * - arp header target ip address
290 * - arp header source ethernet address
293 arprequest(ifp, sip, tip, enaddr)
295 struct in_addr *sip, *tip;
299 struct ether_header *eh;
300 struct arc_header *arh;
303 static u_char llcx[] = { 0x82, 0x40, LLC_SNAP_LSAP, LLC_SNAP_LSAP,
304 LLC_UI, 0x00, 0x00, 0x00, 0x08, 0x06 };
307 if ((m = m_gethdr(MB_DONTWAIT, MT_DATA)) == NULL)
309 m->m_pkthdr.rcvif = (struct ifnet *)0;
310 switch (ifp->if_type) {
312 ar_hrd = htons(ARPHRD_ARCNET);
314 m->m_len = arphdr_len2(ifp->if_addrlen, sizeof(struct in_addr));
315 m->m_pkthdr.len = m->m_len;
316 MH_ALIGN(m, m->m_len);
318 arh = (struct arc_header *)sa.sa_data;
319 arh->arc_dhost = ifp->if_broadcastaddr[0];
320 arh->arc_type = ARCTYPE_ARP;
322 ah = mtod(m, struct arphdr *);
326 ar_hrd = htons(ARPHRD_IEEE802);
328 m->m_len = sizeof(llcx) +
329 arphdr_len2(ifp->if_addrlen, sizeof(struct in_addr));
330 m->m_pkthdr.len = m->m_len;
331 MH_ALIGN(m, m->m_len);
333 (void)memcpy(mtod(m, caddr_t), llcx, sizeof(llcx));
334 memcpy(sa.sa_data, ifp->if_broadcastaddr, ifp->if_addrlen);
335 (void)memcpy(sa.sa_data + 6, enaddr, 6);
336 sa.sa_data[6] |= TR_RII;
337 sa.sa_data[12] = TR_AC;
338 sa.sa_data[13] = TR_LLC_FRAME;
340 ah = (struct arphdr *)(mtod(m, char *) + sizeof(llcx));
345 * This may not be correct for types not explicitly
346 * listed, but this is our best guess
349 ar_hrd = htons(ARPHRD_ETHER);
351 m->m_len = arphdr_len2(ifp->if_addrlen, sizeof(struct in_addr));
352 m->m_pkthdr.len = m->m_len;
353 MH_ALIGN(m, m->m_len);
355 eh = (struct ether_header *)sa.sa_data;
356 /* if_output will not swap */
357 eh->ether_type = htons(ETHERTYPE_ARP);
358 memcpy(eh->ether_dhost, ifp->if_broadcastaddr, ifp->if_addrlen);
360 ah = mtod(m, struct arphdr *);
365 ah->ar_pro = htons(ETHERTYPE_IP);
366 ah->ar_hln = ifp->if_addrlen; /* hardware address length */
367 ah->ar_pln = sizeof(struct in_addr); /* protocol address length */
368 ah->ar_op = htons(ARPOP_REQUEST);
369 (void)memcpy(ar_sha(ah), enaddr, ah->ar_hln);
370 memset(ar_tha(ah), 0, ah->ar_hln);
371 (void)memcpy(ar_spa(ah), sip, ah->ar_pln);
372 (void)memcpy(ar_tpa(ah), tip, ah->ar_pln);
374 sa.sa_family = AF_UNSPEC;
375 sa.sa_len = sizeof(sa);
376 (*ifp->if_output)(ifp, m, &sa, (struct rtentry *)0);
380 * Resolve an IP address into an ethernet address. If success,
381 * desten is filled in. If there is no entry in arptab,
382 * set one up and broadcast a request for the IP address.
383 * Hold onto this mbuf and resend it once the address
384 * is finally resolved. A return value of 1 indicates
385 * that desten has been filled in and the packet should be sent
386 * normally; a 0 return indicates that the packet has been
387 * taken over here, either now or for later transmission.
390 arpresolve(ifp, rt, m, dst, desten, rt0)
394 struct sockaddr *dst;
398 struct llinfo_arp *la = 0;
399 struct sockaddr_dl *sdl;
401 if (m->m_flags & M_BCAST) { /* broadcast */
402 memcpy(desten, ifp->if_broadcastaddr, ifp->if_addrlen);
405 if (m->m_flags & M_MCAST && ifp->if_type != IFT_ARCNET) {/* multicast */
406 ETHER_MAP_IP_MULTICAST(&SIN(dst)->sin_addr, desten);
410 la = (struct llinfo_arp *)rt->rt_llinfo;
412 la = arplookup(SIN(dst)->sin_addr.s_addr, 1, 0);
416 if (la == 0 || rt == 0) {
417 log(LOG_DEBUG, "arpresolve: can't allocate llinfo for %s%s%s\n",
418 inet_ntoa(SIN(dst)->sin_addr), la ? "la" : "",
423 sdl = SDL(rt->rt_gateway);
425 * Check the address family and length is valid, the address
426 * is resolved; otherwise, try to resolve.
428 if ((rt->rt_expire == 0 || rt->rt_expire > time_second) &&
429 sdl->sdl_family == AF_LINK && sdl->sdl_alen != 0) {
431 * If entry has an expiry time and it is approaching,
432 * see if we need to send an ARP request within this
433 * arpt_down interval.
435 if ((rt->rt_expire != 0) &&
436 (time_second + (arp_maxtries - la->la_preempt) * arpt_down
439 &SIN(rt->rt_ifa->ifa_addr)->sin_addr,
445 bcopy(LLADDR(sdl), desten, sdl->sdl_alen);
449 * If ARP is disabled on this interface, stop.
451 * Probably should not allocate empty llinfo struct if we are
452 * not going to be sending out an arp request.
454 if (ifp->if_flags & IFF_NOARP) {
459 * There is an arptab entry, but no ethernet address
460 * response yet. Replace the held mbuf with this
464 m_freem(la->la_hold);
467 rt->rt_flags &= ~RTF_REJECT;
468 if (la->la_asked == 0 || rt->rt_expire != time_second) {
469 rt->rt_expire = time_second;
470 if (la->la_asked++ < arp_maxtries) {
472 &SIN(rt->rt_ifa->ifa_addr)->sin_addr,
476 rt->rt_flags |= RTF_REJECT;
477 rt->rt_expire += arpt_down;
478 la->la_preempt = la->la_asked = 0;
487 * Common length and type checks are done here,
488 * then the protocol-specific routine is called.
491 arpintr(struct netmsg *msg)
493 struct mbuf *m = ((struct netmsg_packet *)msg)->nm_packet;
497 if (m->m_len < sizeof(struct arphdr) &&
498 ((m = m_pullup(m, sizeof(struct arphdr))) == NULL)) {
499 log(LOG_ERR, "arp: runt packet -- m_pullup failed\n");
502 ar = mtod(m, struct arphdr *);
504 ar_hrd = ntohs(ar->ar_hrd);
505 if (ar_hrd != ARPHRD_ETHER &&
506 ar_hrd != ARPHRD_IEEE802 &&
507 ar_hrd != ARPHRD_ARCNET) {
509 "arp: unknown hardware address format (0x%2D)\n",
510 (unsigned char *)&ar->ar_hrd, "");
514 if (m->m_pkthdr.len < arphdr_len(ar) &&
515 (m = m_pullup(m, arphdr_len(ar))) == NULL) {
516 log(LOG_ERR, "arp: runt packet\n");
520 switch (ntohs(ar->ar_pro)) {
530 lwkt_replymsg(&msg->nm_lmsg, 0);
536 * ARP for Internet protocols on 10 Mb/s Ethernet.
537 * Algorithm is that given in RFC 826.
538 * In addition, a sanity check is performed on the sender
539 * protocol address, to catch impersonators.
540 * We no longer handle negotiations for use of trailer protocol:
541 * Formerly, ARP replied for protocol type ETHERTYPE_TRAIL sent
542 * along with IP replies if we wanted trailers sent to us,
543 * and also sent them in response to IP replies.
544 * This allowed either end to announce the desire to receive
546 * We no longer reply to requests for ETHERTYPE_TRAIL protocol either,
547 * but formerly didn't normally send requests.
549 static int log_arp_wrong_iface = 1;
551 SYSCTL_INT(_net_link_ether_inet, OID_AUTO, log_arp_wrong_iface, CTLFLAG_RW,
552 &log_arp_wrong_iface, 0,
553 "log arp packets arriving on the wrong interface");
560 struct ifnet *ifp = m->m_pkthdr.rcvif;
561 struct ether_header *eh;
562 struct arc_header *arh;
563 struct iso88025_header *th = (struct iso88025_header *)0;
564 struct iso88025_sockaddr_dl_data *trld;
565 struct llinfo_arp *la = 0;
568 struct in_ifaddr *ia;
569 struct sockaddr_dl *sdl;
571 struct in_addr isaddr, itaddr, myaddr;
575 req_len = arphdr_len2(ifp->if_addrlen, sizeof(struct in_addr));
576 if (m->m_len < req_len && (m = m_pullup(m, req_len)) == NULL) {
577 log(LOG_ERR, "in_arp: runt packet -- m_pullup failed\n");
581 ah = mtod(m, struct arphdr *);
582 op = ntohs(ah->ar_op);
583 (void)memcpy(&isaddr, ar_spa(ah), sizeof (isaddr));
584 (void)memcpy(&itaddr, ar_tpa(ah), sizeof (itaddr));
586 #define BRIDGE_TEST (do_bridge)
588 #define BRIDGE_TEST (0) /* cc will optimise the test away */
591 * For a bridge, we want to check the address irrespective
592 * of the receive interface. (This will change slightly
593 * when we have clusters of interfaces).
595 LIST_FOREACH(ia, INADDR_HASH(itaddr.s_addr), ia_hash)
596 if ((BRIDGE_TEST || (ia->ia_ifp == ifp)) &&
597 itaddr.s_addr == ia->ia_addr.sin_addr.s_addr)
599 LIST_FOREACH(ia, INADDR_HASH(isaddr.s_addr), ia_hash)
600 if ((BRIDGE_TEST || (ia->ia_ifp == ifp)) &&
601 isaddr.s_addr == ia->ia_addr.sin_addr.s_addr)
604 * No match, use the first inet address on the receive interface
605 * as a dummy address for the rest of the function.
607 TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link)
608 if (ifa->ifa_addr && ifa->ifa_addr->sa_family == AF_INET) {
613 * If bridging, fall back to using any inet address.
614 * This is probably incorrect, the right way being try to match
615 * addresses for interfaces in the same cluster, so if we
616 * get here we should always drop the packet.
619 (ia = TAILQ_FIRST(&in_ifaddrhead)) == NULL) {
624 myaddr = ia->ia_addr.sin_addr;
625 if (!bcmp(ar_sha(ah), IF_LLADDR(ifp), ifp->if_addrlen)) {
626 m_freem(m); /* it's from me, ignore it. */
629 if (!bcmp(ar_sha(ah), ifp->if_broadcastaddr, ifp->if_addrlen)) {
631 "arp: link address is broadcast for IP address %s!\n",
636 if (isaddr.s_addr == myaddr.s_addr) {
638 "arp: %*D is using my IP address %s!\n",
639 ifp->if_addrlen, (u_char *)ar_sha(ah), ":",
644 la = arplookup(isaddr.s_addr, itaddr.s_addr == myaddr.s_addr, 0);
645 if (la && (rt = la->la_rt) && (sdl = SDL(rt->rt_gateway))) {
646 /* the following is not an error when doing bridging */
647 if (!BRIDGE_TEST && rt->rt_ifp != ifp) {
648 if (log_arp_wrong_iface)
649 log(LOG_ERR, "arp: %s is on %s but got reply from %*D on %s\n",
651 rt->rt_ifp->if_xname,
652 ifp->if_addrlen, (u_char *)ar_sha(ah), ":",
657 bcmp(ar_sha(ah), LLADDR(sdl), sdl->sdl_alen)) {
659 log(LOG_INFO, "arp: %s moved from %*D to %*D on %s\n",
661 ifp->if_addrlen, (u_char *)LLADDR(sdl), ":",
662 ifp->if_addrlen, (u_char *)ar_sha(ah), ":",
666 "arp: %*D attempts to modify permanent entry for %s on %s\n",
667 ifp->if_addrlen, (u_char *)ar_sha(ah), ":",
668 inet_ntoa(isaddr), ifp->if_xname);
673 * sanity check for the address length.
674 * XXX this does not work for protocols with variable address
678 sdl->sdl_alen != ah->ar_hln) {
680 "arp from %*D: new addr len %d, was %d",
681 ifp->if_addrlen, (u_char *) ar_sha(ah), ":",
682 ah->ar_hln, sdl->sdl_alen);
684 if (ifp->if_addrlen != ah->ar_hln) {
686 "arp from %*D: addr len: new %d, i/f %d (ignored)",
687 ifp->if_addrlen, (u_char *) ar_sha(ah), ":",
688 ah->ar_hln, ifp->if_addrlen);
691 (void)memcpy(LLADDR(sdl), ar_sha(ah),
692 sdl->sdl_alen = ah->ar_hln);
694 * If we receive an arp from a token-ring station over
695 * a token-ring nic then try to save the source
698 if (ifp->if_type == IFT_ISO88025) {
699 th = (struct iso88025_header *)m->m_pkthdr.header;
700 trld = SDL_ISO88025(sdl);
701 rif_len = TR_RCF_RIFLEN(th->rcf);
702 if ((th->iso88025_shost[0] & TR_RII) &&
704 trld->trld_rcf = th->rcf;
705 trld->trld_rcf ^= htons(TR_RCF_DIR);
706 memcpy(trld->trld_route, th->rd, rif_len - 2);
707 trld->trld_rcf &= ~htons(TR_RCF_BCST_MASK);
709 * Set up source routing information for
712 m->m_data -= rif_len;
714 m->m_pkthdr.len += rif_len;
716 th->iso88025_shost[0] &= ~TR_RII;
721 m->m_pkthdr.len += 8;
722 th->rcf = trld->trld_rcf;
725 rt->rt_expire = time_second + arpt_keep;
726 rt->rt_flags &= ~RTF_REJECT;
727 la->la_preempt = la->la_asked = 0;
729 (*ifp->if_output)(ifp, la->la_hold,
735 if (op != ARPOP_REQUEST) {
739 if (itaddr.s_addr == myaddr.s_addr) {
740 /* I am the target */
741 (void)memcpy(ar_tha(ah), ar_sha(ah), ah->ar_hln);
742 (void)memcpy(ar_sha(ah), IF_LLADDR(ifp), ah->ar_hln);
744 la = arplookup(itaddr.s_addr, 0, SIN_PROXY);
746 struct sockaddr_in sin;
753 bzero(&sin, sizeof sin);
754 sin.sin_family = AF_INET;
755 sin.sin_len = sizeof sin;
756 sin.sin_addr = itaddr;
758 rt = rtalloc1((struct sockaddr *)&sin, 0, 0UL);
764 * Don't send proxies for nodes on the same interface
765 * as this one came out of, or we'll get into a fight
766 * over who claims what Ether address.
768 if (rt->rt_ifp == ifp) {
773 (void)memcpy(ar_tha(ah), ar_sha(ah), ah->ar_hln);
774 (void)memcpy(ar_sha(ah), IF_LLADDR(ifp), ah->ar_hln);
777 printf("arp: proxying for %s\n",
782 (void)memcpy(ar_tha(ah), ar_sha(ah), ah->ar_hln);
783 sdl = SDL(rt->rt_gateway);
784 (void)memcpy(ar_sha(ah), LLADDR(sdl), ah->ar_hln);
788 (void)memcpy(ar_tpa(ah), ar_spa(ah), ah->ar_pln);
789 (void)memcpy(ar_spa(ah), &itaddr, ah->ar_pln);
790 ah->ar_op = htons(ARPOP_REPLY);
791 ah->ar_pro = htons(ETHERTYPE_IP); /* let's be sure! */
792 switch (ifp->if_type) {
794 arh = (struct arc_header *)sa.sa_data;
795 arh->arc_dhost = *ar_tha(ah);
796 arh->arc_type = ARCTYPE_ARP;
800 /* Re-arrange the source/dest address */
801 memcpy(th->iso88025_dhost, th->iso88025_shost,
802 sizeof(th->iso88025_dhost));
803 memcpy(th->iso88025_shost, IF_LLADDR(ifp),
804 sizeof(th->iso88025_shost));
805 /* Set the source routing bit if neccesary */
806 if (th->iso88025_dhost[0] & TR_RII) {
807 th->iso88025_dhost[0] &= ~TR_RII;
808 if (TR_RCF_RIFLEN(th->rcf) > 2)
809 th->iso88025_shost[0] |= TR_RII;
811 /* Copy the addresses, ac and fc into sa_data */
812 memcpy(sa.sa_data, th->iso88025_dhost,
813 sizeof(th->iso88025_dhost) * 2);
814 sa.sa_data[(sizeof(th->iso88025_dhost) * 2)] = TR_AC;
815 sa.sa_data[(sizeof(th->iso88025_dhost) * 2) + 1] = TR_LLC_FRAME;
820 * May not be correct for types not explictly
821 * listed, but it is our best guess.
824 eh = (struct ether_header *)sa.sa_data;
825 (void)memcpy(eh->ether_dhost, ar_tha(ah),
826 sizeof(eh->ether_dhost));
827 eh->ether_type = htons(ETHERTYPE_ARP);
830 sa.sa_family = AF_UNSPEC;
831 sa.sa_len = sizeof(sa);
832 (*ifp->if_output)(ifp, m, &sa, (struct rtentry *)0);
842 struct llinfo_arp *la;
844 struct rtentry *rt = la->la_rt;
845 struct sockaddr_dl *sdl;
848 if (rt->rt_refcnt > 0 && (sdl = SDL(rt->rt_gateway)) &&
849 sdl->sdl_family == AF_LINK) {
851 la->la_preempt = la->la_asked = 0;
852 rt->rt_flags &= ~RTF_REJECT;
855 rtrequest(RTM_DELETE, rt_key(rt), (struct sockaddr *)0, rt_mask(rt),
856 0, (struct rtentry **)0);
859 * Lookup or enter a new address in arptab.
861 static struct llinfo_arp *
862 arplookup(addr, create, proxy)
867 static struct sockaddr_inarp sin = {sizeof(sin), AF_INET };
870 sin.sin_addr.s_addr = addr;
871 sin.sin_other = proxy ? SIN_PROXY : 0;
872 rt = rtalloc1((struct sockaddr *)&sin, create, 0UL);
877 if (rt->rt_flags & RTF_GATEWAY)
878 why = "host is not on local network";
879 else if ((rt->rt_flags & RTF_LLINFO) == 0)
880 why = "could not allocate llinfo";
881 else if (rt->rt_gateway->sa_family != AF_LINK)
882 why = "gateway route is not ours";
886 log(LOG_DEBUG, "arplookup %s failed: %s\n",
887 inet_ntoa(sin.sin_addr), why);
890 /* if there are no references to this route, purge it */
891 if (rt->rt_refcnt <= 0 &&
892 (rt->rt_flags & RTF_WASCLONED) == RTF_WASCLONED) {
893 rtrequest(RTM_DELETE,
894 (struct sockaddr *)rt_key(rt), rt->rt_gateway,
895 rt_mask(rt), rt->rt_flags, 0);
899 return ((struct llinfo_arp *)rt->rt_llinfo);
907 if (ntohl(IA_SIN(ifa)->sin_addr.s_addr) != INADDR_ANY)
908 arprequest(ifp, &IA_SIN(ifa)->sin_addr,
909 &IA_SIN(ifa)->sin_addr, IF_LLADDR(ifp));
910 ifa->ifa_rtrequest = arp_rtrequest;
911 ifa->ifa_flags |= RTF_CLONING;
917 LIST_INIT(&llinfo_arp);
918 netisr_register(NETISR_ARP, cpu0_portfn, arpintr);
921 SYSINIT(arp, SI_SUB_PROTO_DOMAIN, SI_ORDER_ANY, arp_init, 0);