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
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 DragonFly Project nor the names of its
16 * contributors may be used to endorse or promote products derived
17 * from this software without specific, prior written permission.
19 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
21 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
22 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
23 * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
24 * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
25 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
26 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
27 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
28 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
29 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34 * Copyright (c) 2004, 2005 Jeffrey M. Hsu. All rights reserved.
36 * License terms: all terms for the DragonFly license above plus the following:
38 * 4. All advertising materials mentioning features or use of this software
39 * must display the following acknowledgement:
41 * This product includes software developed by Jeffrey M. Hsu
42 * for the DragonFly Project.
44 * This requirement may be waived with permission from Jeffrey Hsu.
45 * Permission will be granted to any DragonFly user for free.
46 * This requirement will sunset and may be removed on Jan 31, 2006,
47 * after which the standard DragonFly license (as shown above) will
52 * Copyright (c) 1982, 1986, 1988, 1993
53 * The Regents of the University of California. All rights reserved.
55 * Redistribution and use in source and binary forms, with or without
56 * modification, are permitted provided that the following conditions
58 * 1. Redistributions of source code must retain the above copyright
59 * notice, this list of conditions and the following disclaimer.
60 * 2. Redistributions in binary form must reproduce the above copyright
61 * notice, this list of conditions and the following disclaimer in the
62 * documentation and/or other materials provided with the distribution.
63 * 3. All advertising materials mentioning features or use of this software
64 * must display the following acknowledgement:
65 * This product includes software developed by the University of
66 * California, Berkeley and its contributors.
67 * 4. Neither the name of the University nor the names of its contributors
68 * may be used to endorse or promote products derived from this software
69 * without specific prior written permission.
71 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
72 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
73 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
74 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
75 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
76 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
77 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
78 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
79 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
80 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
83 * @(#)if_ether.c 8.1 (Berkeley) 6/10/93
84 * $FreeBSD: src/sys/netinet/if_ether.c,v 1.64.2.23 2003/04/11 07:23:15 fjoe Exp $
85 * $DragonFly: src/sys/netinet/if_ether.c,v 1.28 2005/11/28 17:13:46 dillon Exp $
89 * Ethernet address resolution protocol.
91 * add "inuse/lock" bit (or ref. count) along with valid bit
97 #include <sys/param.h>
98 #include <sys/kernel.h>
99 #include <sys/queue.h>
100 #include <sys/sysctl.h>
101 #include <sys/systm.h>
102 #include <sys/mbuf.h>
103 #include <sys/malloc.h>
104 #include <sys/socket.h>
105 #include <sys/syslog.h>
107 #include <sys/thread2.h>
108 #include <sys/msgport2.h>
111 #include <net/if_dl.h>
112 #include <net/if_types.h>
113 #include <net/route.h>
114 #include <net/netisr.h>
115 #include <net/if_llc.h>
117 #include <net/ethernet.h>
118 #include <net/bridge/bridge.h>
121 #include <netinet/in.h>
122 #include <netinet/in_var.h>
123 #include <netinet/if_ether.h>
125 #include <net/if_arc.h>
126 #include <net/iso88025.h>
128 #define SIN(s) ((struct sockaddr_in *)s)
129 #define SDL(s) ((struct sockaddr_dl *)s)
131 SYSCTL_DECL(_net_link_ether);
132 SYSCTL_NODE(_net_link_ether, PF_INET, inet, CTLFLAG_RW, 0, "");
135 static int arpt_prune = (5*60*1); /* walk list every 5 minutes */
136 static int arpt_keep = (20*60); /* once resolved, good for 20 more minutes */
137 static int arpt_down = 20; /* once declared down, don't send for 20 sec */
139 SYSCTL_INT(_net_link_ether_inet, OID_AUTO, prune_intvl, CTLFLAG_RW,
141 SYSCTL_INT(_net_link_ether_inet, OID_AUTO, max_age, CTLFLAG_RW,
143 SYSCTL_INT(_net_link_ether_inet, OID_AUTO, host_down_time, CTLFLAG_RW,
146 #define rt_expire rt_rmx.rmx_expire
149 LIST_ENTRY(llinfo_arp) la_le;
150 struct rtentry *la_rt;
151 struct mbuf *la_hold; /* last packet until resolved/timeout */
152 u_short la_preempt; /* countdown for pre-expiry arps */
153 u_short la_asked; /* #times we QUERIED following expiration */
156 static LIST_HEAD(, llinfo_arp) llinfo_arp;
158 static int arp_maxtries = 5;
159 static int useloopback = 1; /* use loopback interface for local traffic */
160 static int arp_proxyall = 0;
162 SYSCTL_INT(_net_link_ether_inet, OID_AUTO, maxtries, CTLFLAG_RW,
163 &arp_maxtries, 0, "");
164 SYSCTL_INT(_net_link_ether_inet, OID_AUTO, useloopback, CTLFLAG_RW,
165 &useloopback, 0, "");
166 SYSCTL_INT(_net_link_ether_inet, OID_AUTO, proxyall, CTLFLAG_RW,
167 &arp_proxyall, 0, "");
169 static void arp_rtrequest (int, struct rtentry *, struct rt_addrinfo *);
170 static void arprequest (struct ifnet *,
171 struct in_addr *, struct in_addr *, u_char *);
172 static int arpintr(struct netmsg *);
173 static void arptfree (struct llinfo_arp *);
174 static void arptimer (void *);
175 static struct llinfo_arp
176 *arplookup (in_addr_t addr, boolean_t create, boolean_t proxy);
178 static void in_arpinput (struct mbuf *);
181 static struct callout arptimer_ch;
184 * Timeout routine. Age arp_tab entries periodically.
188 arptimer(void *ignored_arg)
190 struct llinfo_arp *la, *nla;
193 LIST_FOREACH_MUTABLE(la, &llinfo_arp, la_le, nla) {
194 if (la->la_rt->rt_expire && la->la_rt->rt_expire <= time_second)
195 arptfree(la); /* might remove la from llinfo_arp! */
197 callout_reset(&arptimer_ch, arpt_prune * hz, arptimer, NULL);
202 * Parallel to llc_rtrequest.
205 arp_rtrequest(int req, struct rtentry *rt, struct rt_addrinfo *info)
207 struct sockaddr *gate = rt->rt_gateway;
208 struct llinfo_arp *la = rt->rt_llinfo;
210 struct sockaddr_dl null_sdl = { sizeof null_sdl, AF_LINK };
211 static boolean_t arpinit_done;
215 callout_init(&arptimer_ch);
216 callout_reset(&arptimer_ch, hz, arptimer, NULL);
218 if (rt->rt_flags & RTF_GATEWAY)
224 * XXX: If this is a manually added route to interface
225 * such as older version of routed or gated might provide,
226 * restore cloning bit.
228 if (!(rt->rt_flags & RTF_HOST) &&
229 SIN(rt_mask(rt))->sin_addr.s_addr != 0xffffffff)
230 rt->rt_flags |= RTF_CLONING;
231 if (rt->rt_flags & RTF_CLONING) {
233 * Case 1: This route should come from a route to iface.
235 rt_setgate(rt, rt_key(rt),
236 (struct sockaddr *)&null_sdl);
237 gate = rt->rt_gateway;
238 SDL(gate)->sdl_type = rt->rt_ifp->if_type;
239 SDL(gate)->sdl_index = rt->rt_ifp->if_index;
240 rt->rt_expire = time_second;
243 /* Announce a new entry if requested. */
244 if (rt->rt_flags & RTF_ANNOUNCE)
245 arprequest(rt->rt_ifp,
246 &SIN(rt_key(rt))->sin_addr,
247 &SIN(rt_key(rt))->sin_addr,
251 if (gate->sa_family != AF_LINK ||
252 gate->sa_len < sizeof(struct sockaddr_dl)) {
253 log(LOG_DEBUG, "arp_rtrequest: bad gateway value\n");
256 SDL(gate)->sdl_type = rt->rt_ifp->if_type;
257 SDL(gate)->sdl_index = rt->rt_ifp->if_index;
259 break; /* This happens on a route change */
261 * Case 2: This route may come from cloning, or a manual route
262 * add with a LL address.
264 R_Malloc(la, struct llinfo_arp *, sizeof *la);
267 log(LOG_DEBUG, "arp_rtrequest: malloc failed\n");
270 bzero(la, sizeof *la);
272 rt->rt_flags |= RTF_LLINFO;
273 LIST_INSERT_HEAD(&llinfo_arp, la, la_le);
277 * This keeps the multicast addresses from showing up
278 * in `arp -a' listings as unresolved. It's not actually
279 * functional. Then the same for broadcast.
281 if (IN_MULTICAST(ntohl(SIN(rt_key(rt))->sin_addr.s_addr)) &&
282 rt->rt_ifp->if_type != IFT_ARCNET) {
283 ETHER_MAP_IP_MULTICAST(&SIN(rt_key(rt))->sin_addr,
285 SDL(gate)->sdl_alen = 6;
288 if (in_broadcast(SIN(rt_key(rt))->sin_addr, rt->rt_ifp)) {
289 memcpy(LLADDR(SDL(gate)), rt->rt_ifp->if_broadcastaddr,
290 rt->rt_ifp->if_addrlen);
291 SDL(gate)->sdl_alen = rt->rt_ifp->if_addrlen;
296 if (SIN(rt_key(rt))->sin_addr.s_addr ==
297 (IA_SIN(rt->rt_ifa))->sin_addr.s_addr) {
299 * This test used to be
300 * if (loif.if_flags & IFF_UP)
301 * It allowed local traffic to be forced
302 * through the hardware by configuring the
303 * loopback down. However, it causes problems
304 * during network configuration for boards
305 * that can't receive packets they send. It
306 * is now necessary to clear "useloopback" and
307 * remove the route to force traffic out to
311 bcopy(IF_LLADDR(rt->rt_ifp), LLADDR(SDL(gate)),
312 SDL(gate)->sdl_alen = rt->rt_ifp->if_addrlen);
321 LIST_REMOVE(la, la_le);
322 rt->rt_llinfo = NULL;
323 rt->rt_flags &= ~RTF_LLINFO;
324 if (la->la_hold != NULL)
325 m_freem(la->la_hold);
331 * Broadcast an ARP request. Caller specifies:
332 * - arp header source ip address
333 * - arp header target ip address
334 * - arp header source ethernet address
337 arprequest(struct ifnet *ifp, struct in_addr *sip, struct in_addr *tip,
341 struct ether_header *eh;
342 struct arc_header *arh;
345 static u_char llcx[] = { 0x82, 0x40, LLC_SNAP_LSAP, LLC_SNAP_LSAP,
346 LLC_UI, 0x00, 0x00, 0x00, 0x08, 0x06 };
349 if ((m = m_gethdr(MB_DONTWAIT, MT_DATA)) == NULL)
351 m->m_pkthdr.rcvif = (struct ifnet *)NULL;
353 switch (ifp->if_type) {
355 ar_hrd = htons(ARPHRD_ARCNET);
357 m->m_len = arphdr_len2(ifp->if_addrlen, sizeof(struct in_addr));
358 m->m_pkthdr.len = m->m_len;
359 MH_ALIGN(m, m->m_len);
361 arh = (struct arc_header *)sa.sa_data;
362 arh->arc_dhost = ifp->if_broadcastaddr[0];
363 arh->arc_type = ARCTYPE_ARP;
365 ah = mtod(m, struct arphdr *);
369 ar_hrd = htons(ARPHRD_IEEE802);
371 m->m_len = (sizeof llcx) +
372 arphdr_len2(ifp->if_addrlen, sizeof(struct in_addr));
373 m->m_pkthdr.len = m->m_len;
374 MH_ALIGN(m, m->m_len);
376 memcpy(mtod(m, caddr_t), llcx, sizeof llcx);
377 memcpy(sa.sa_data, ifp->if_broadcastaddr, ifp->if_addrlen);
378 memcpy(sa.sa_data + 6, enaddr, 6);
379 sa.sa_data[6] |= TR_RII;
380 sa.sa_data[12] = TR_AC;
381 sa.sa_data[13] = TR_LLC_FRAME;
383 ah = (struct arphdr *)(mtod(m, char *) + sizeof llcx);
388 * This may not be correct for types not explicitly
389 * listed, but this is our best guess
392 ar_hrd = htons(ARPHRD_ETHER);
394 m->m_len = arphdr_len2(ifp->if_addrlen, sizeof(struct in_addr));
395 m->m_pkthdr.len = m->m_len;
396 MH_ALIGN(m, m->m_len);
398 eh = (struct ether_header *)sa.sa_data;
399 /* if_output() will not swap */
400 eh->ether_type = htons(ETHERTYPE_ARP);
401 memcpy(eh->ether_dhost, ifp->if_broadcastaddr, ifp->if_addrlen);
403 ah = mtod(m, struct arphdr *);
408 ah->ar_pro = htons(ETHERTYPE_IP);
409 ah->ar_hln = ifp->if_addrlen; /* hardware address length */
410 ah->ar_pln = sizeof(struct in_addr); /* protocol address length */
411 ah->ar_op = htons(ARPOP_REQUEST);
412 memcpy(ar_sha(ah), enaddr, ah->ar_hln);
413 memset(ar_tha(ah), 0, ah->ar_hln);
414 memcpy(ar_spa(ah), sip, ah->ar_pln);
415 memcpy(ar_tpa(ah), tip, ah->ar_pln);
417 sa.sa_family = AF_UNSPEC;
418 sa.sa_len = sizeof sa;
419 (*ifp->if_output)(ifp, m, &sa, (struct rtentry *)NULL);
423 * Resolve an IP address into an ethernet address. If success,
424 * desten is filled in. If there is no entry in arptab,
425 * set one up and broadcast a request for the IP address.
426 * Hold onto this mbuf and resend it once the address
427 * is finally resolved. A return value of 1 indicates
428 * that desten has been filled in and the packet should be sent
429 * normally; a 0 return indicates that the packet has been
430 * taken over here, either now or for later transmission.
437 struct sockaddr *dst,
441 struct llinfo_arp *la = NULL;
442 struct sockaddr_dl *sdl;
444 if (m->m_flags & M_BCAST) { /* broadcast */
445 memcpy(desten, ifp->if_broadcastaddr, ifp->if_addrlen);
448 if (m->m_flags & M_MCAST && ifp->if_type != IFT_ARCNET) {/* multicast */
449 ETHER_MAP_IP_MULTICAST(&SIN(dst)->sin_addr, desten);
453 if (rt_llroute(dst, rt0, &rt) != 0) {
460 la = arplookup(SIN(dst)->sin_addr.s_addr, TRUE, FALSE);
464 if (la == NULL || rt == NULL) {
465 log(LOG_DEBUG, "arpresolve: can't allocate llinfo for %s%s%s\n",
466 inet_ntoa(SIN(dst)->sin_addr), la ? "la" : " ",
471 sdl = SDL(rt->rt_gateway);
473 * Check the address family and length is valid, the address
474 * is resolved; otherwise, try to resolve.
476 if ((rt->rt_expire == 0 || rt->rt_expire > time_second) &&
477 sdl->sdl_family == AF_LINK && sdl->sdl_alen != 0) {
479 * If entry has an expiry time and it is approaching,
480 * see if we need to send an ARP request within this
481 * arpt_down interval.
483 if ((rt->rt_expire != 0) &&
484 (time_second + la->la_preempt > rt->rt_expire)) {
486 &SIN(rt->rt_ifa->ifa_addr)->sin_addr,
492 bcopy(LLADDR(sdl), desten, sdl->sdl_alen);
496 * If ARP is disabled on this interface, stop.
498 * Probably should not allocate empty llinfo struct if we are
499 * not going to be sending out an arp request.
501 if (ifp->if_flags & IFF_NOARP) {
506 * There is an arptab entry, but no ethernet address
507 * response yet. Replace the held mbuf with this
510 if (la->la_hold != NULL)
511 m_freem(la->la_hold);
513 if (rt->rt_expire || ((rt->rt_flags & RTF_STATIC) && !sdl->sdl_alen)) {
514 rt->rt_flags &= ~RTF_REJECT;
515 if (la->la_asked == 0 || rt->rt_expire != time_second) {
516 rt->rt_expire = time_second;
517 if (la->la_asked++ < arp_maxtries) {
519 &SIN(rt->rt_ifa->ifa_addr)->sin_addr,
523 rt->rt_flags |= RTF_REJECT;
524 rt->rt_expire += arpt_down;
526 la->la_preempt = arp_maxtries;
535 * Common length and type checks are done here,
536 * then the protocol-specific routine is called.
539 arpintr(struct netmsg *msg)
541 struct mbuf *m = ((struct netmsg_packet *)msg)->nm_packet;
545 if (m->m_len < sizeof(struct arphdr) &&
546 ((m = m_pullup(m, sizeof(struct arphdr))) == NULL)) {
547 log(LOG_ERR, "arp: runt packet -- m_pullup failed\n");
550 ar = mtod(m, struct arphdr *);
552 ar_hrd = ntohs(ar->ar_hrd);
553 if (ar_hrd != ARPHRD_ETHER &&
554 ar_hrd != ARPHRD_IEEE802 &&
555 ar_hrd != ARPHRD_ARCNET) {
557 "arp: unknown hardware address format (0x%2D)\n",
558 (unsigned char *)&ar->ar_hrd, "");
562 if (m->m_pkthdr.len < arphdr_len(ar) &&
563 (m = m_pullup(m, arphdr_len(ar))) == NULL) {
564 log(LOG_ERR, "arp: runt packet\n");
568 switch (ntohs(ar->ar_pro)) {
578 lwkt_replymsg(&msg->nm_lmsg, 0);
584 * ARP for Internet protocols on 10 Mb/s Ethernet.
585 * Algorithm is that given in RFC 826.
586 * In addition, a sanity check is performed on the sender
587 * protocol address, to catch impersonators.
588 * We no longer handle negotiations for use of trailer protocol:
589 * Formerly, ARP replied for protocol type ETHERTYPE_TRAIL sent
590 * along with IP replies if we wanted trailers sent to us,
591 * and also sent them in response to IP replies.
592 * This allowed either end to announce the desire to receive
594 * We no longer reply to requests for ETHERTYPE_TRAIL protocol either,
595 * but formerly didn't normally send requests.
597 static int log_arp_wrong_iface = 1;
598 SYSCTL_INT(_net_link_ether_inet, OID_AUTO, log_arp_wrong_iface, CTLFLAG_RW,
599 &log_arp_wrong_iface, 0,
600 "log arp packets arriving on the wrong interface");
603 in_arpinput(struct mbuf *m)
606 struct ifnet *ifp = m->m_pkthdr.rcvif;
607 struct ether_header *eh;
608 struct arc_header *arh;
609 struct iso88025_header *th = (struct iso88025_header *)NULL;
610 struct iso88025_sockaddr_dl_data *trld;
611 struct llinfo_arp *la = NULL;
614 struct in_ifaddr *ia;
615 struct sockaddr_dl *sdl;
617 struct in_addr isaddr, itaddr, myaddr;
621 req_len = arphdr_len2(ifp->if_addrlen, sizeof(struct in_addr));
622 if (m->m_len < req_len && (m = m_pullup(m, req_len)) == NULL) {
623 log(LOG_ERR, "in_arp: runt packet -- m_pullup failed\n");
627 ah = mtod(m, struct arphdr *);
628 op = ntohs(ah->ar_op);
629 memcpy(&isaddr, ar_spa(ah), sizeof isaddr);
630 memcpy(&itaddr, ar_tpa(ah), sizeof itaddr);
632 #define BRIDGE_TEST (do_bridge)
634 #define BRIDGE_TEST (0) /* cc will optimise the test away */
637 * For a bridge, we want to check the address irrespective
638 * of the receive interface. (This will change slightly
639 * when we have clusters of interfaces).
641 LIST_FOREACH(ia, INADDR_HASH(itaddr.s_addr), ia_hash)
642 if ((BRIDGE_TEST || (ia->ia_ifp == ifp)) &&
643 itaddr.s_addr == ia->ia_addr.sin_addr.s_addr)
645 LIST_FOREACH(ia, INADDR_HASH(isaddr.s_addr), ia_hash)
646 if ((BRIDGE_TEST || (ia->ia_ifp == ifp)) &&
647 isaddr.s_addr == ia->ia_addr.sin_addr.s_addr)
650 * No match, use the first inet address on the receive interface
651 * as a dummy address for the rest of the function.
653 TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link)
654 if (ifa->ifa_addr && ifa->ifa_addr->sa_family == AF_INET) {
659 * If bridging, fall back to using any inet address.
660 * This is probably incorrect, the right way being try to match
661 * addresses for interfaces in the same cluster, so if we
662 * get here we should always drop the packet.
665 (ia = TAILQ_FIRST(&in_ifaddrhead)) == NULL) {
670 myaddr = ia->ia_addr.sin_addr;
671 if (!bcmp(ar_sha(ah), IF_LLADDR(ifp), ifp->if_addrlen)) {
672 m_freem(m); /* it's from me, ignore it. */
675 if (!bcmp(ar_sha(ah), ifp->if_broadcastaddr, ifp->if_addrlen)) {
677 "arp: link address is broadcast for IP address %s!\n",
682 if (isaddr.s_addr == myaddr.s_addr && myaddr.s_addr != 0) {
684 "arp: %*D is using my IP address %s!\n",
685 ifp->if_addrlen, (u_char *)ar_sha(ah), ":",
690 la = arplookup(isaddr.s_addr, (itaddr.s_addr == myaddr.s_addr), FALSE);
691 if (la && (rt = la->la_rt) && (sdl = SDL(rt->rt_gateway))) {
692 /* the following is not an error when doing bridging */
693 if (!BRIDGE_TEST && rt->rt_ifp != ifp) {
694 if (log_arp_wrong_iface)
696 "arp: %s is on %s but got reply from %*D on %s\n",
698 rt->rt_ifp->if_xname,
699 ifp->if_addrlen, (u_char *)ar_sha(ah), ":",
704 bcmp(ar_sha(ah), LLADDR(sdl), sdl->sdl_alen)) {
707 "arp: %s moved from %*D to %*D on %s\n",
709 ifp->if_addrlen, (u_char *)LLADDR(sdl), ":",
710 ifp->if_addrlen, (u_char *)ar_sha(ah), ":",
714 "arp: %*D attempts to modify permanent entry for %s on %s\n",
715 ifp->if_addrlen, (u_char *)ar_sha(ah), ":",
716 inet_ntoa(isaddr), ifp->if_xname);
721 * sanity check for the address length.
722 * XXX this does not work for protocols with variable address
726 sdl->sdl_alen != ah->ar_hln) {
728 "arp from %*D: new addr len %d, was %d",
729 ifp->if_addrlen, (u_char *) ar_sha(ah), ":",
730 ah->ar_hln, sdl->sdl_alen);
732 if (ifp->if_addrlen != ah->ar_hln) {
734 "arp from %*D: addr len: new %d, i/f %d (ignored)",
735 ifp->if_addrlen, (u_char *) ar_sha(ah), ":",
736 ah->ar_hln, ifp->if_addrlen);
739 memcpy(LLADDR(sdl), ar_sha(ah), sdl->sdl_alen = ah->ar_hln);
741 * If we receive an arp from a token-ring station over
742 * a token-ring nic then try to save the source
745 if (ifp->if_type == IFT_ISO88025) {
746 th = (struct iso88025_header *)m->m_pkthdr.header;
747 trld = SDL_ISO88025(sdl);
748 rif_len = TR_RCF_RIFLEN(th->rcf);
749 if ((th->iso88025_shost[0] & TR_RII) &&
751 trld->trld_rcf = th->rcf;
752 trld->trld_rcf ^= htons(TR_RCF_DIR);
753 memcpy(trld->trld_route, th->rd, rif_len - 2);
754 trld->trld_rcf &= ~htons(TR_RCF_BCST_MASK);
756 * Set up source routing information for
759 m->m_data -= rif_len;
761 m->m_pkthdr.len += rif_len;
763 th->iso88025_shost[0] &= ~TR_RII;
768 m->m_pkthdr.len += 8;
769 th->rcf = trld->trld_rcf;
772 rt->rt_expire = time_second + arpt_keep;
773 rt->rt_flags &= ~RTF_REJECT;
775 la->la_preempt = arp_maxtries;
776 if (la->la_hold != NULL) {
777 m_adj(la->la_hold, sizeof(struct ether_header));
778 lwkt_serialize_enter(ifp->if_serializer);
779 (*ifp->if_output)(ifp, la->la_hold, rt_key(rt), rt);
780 lwkt_serialize_exit(ifp->if_serializer);
785 if (op != ARPOP_REQUEST) {
789 if (itaddr.s_addr == myaddr.s_addr) {
790 /* I am the target */
791 memcpy(ar_tha(ah), ar_sha(ah), ah->ar_hln);
792 memcpy(ar_sha(ah), IF_LLADDR(ifp), ah->ar_hln);
794 la = arplookup(itaddr.s_addr, FALSE, SIN_PROXY);
796 struct sockaddr_in sin;
803 bzero(&sin, sizeof sin);
804 sin.sin_family = AF_INET;
805 sin.sin_len = sizeof sin;
806 sin.sin_addr = itaddr;
808 rt = rtpurelookup((struct sockaddr *)&sin);
815 * Don't send proxies for nodes on the same interface
816 * as this one came out of, or we'll get into a fight
817 * over who claims what Ether address.
819 if (rt->rt_ifp == ifp) {
823 memcpy(ar_tha(ah), ar_sha(ah), ah->ar_hln);
824 memcpy(ar_sha(ah), IF_LLADDR(ifp), ah->ar_hln);
826 printf("arp: proxying for %s\n", inet_ntoa(itaddr));
830 memcpy(ar_tha(ah), ar_sha(ah), ah->ar_hln);
831 sdl = SDL(rt->rt_gateway);
832 memcpy(ar_sha(ah), LLADDR(sdl), ah->ar_hln);
836 memcpy(ar_tpa(ah), ar_spa(ah), ah->ar_pln);
837 memcpy(ar_spa(ah), &itaddr, ah->ar_pln);
838 ah->ar_op = htons(ARPOP_REPLY);
839 ah->ar_pro = htons(ETHERTYPE_IP); /* let's be sure! */
840 switch (ifp->if_type) {
842 arh = (struct arc_header *)sa.sa_data;
843 arh->arc_dhost = *ar_tha(ah);
844 arh->arc_type = ARCTYPE_ARP;
847 /* Re-arrange the source/dest address */
848 memcpy(th->iso88025_dhost, th->iso88025_shost,
849 sizeof th->iso88025_dhost);
850 memcpy(th->iso88025_shost, IF_LLADDR(ifp),
851 sizeof th->iso88025_shost);
852 /* Set the source routing bit if neccesary */
853 if (th->iso88025_dhost[0] & TR_RII) {
854 th->iso88025_dhost[0] &= ~TR_RII;
855 if (TR_RCF_RIFLEN(th->rcf) > 2)
856 th->iso88025_shost[0] |= TR_RII;
858 /* Copy the addresses, ac and fc into sa_data */
859 memcpy(sa.sa_data, th->iso88025_dhost,
860 (sizeof th->iso88025_dhost) * 2);
861 sa.sa_data[(sizeof th->iso88025_dhost) * 2] = TR_AC;
862 sa.sa_data[(sizeof th->iso88025_dhost) * 2 + 1] = TR_LLC_FRAME;
867 * May not be correct for types not explictly
868 * listed, but it is our best guess.
871 eh = (struct ether_header *)sa.sa_data;
872 memcpy(eh->ether_dhost, ar_tha(ah), sizeof eh->ether_dhost);
873 eh->ether_type = htons(ETHERTYPE_ARP);
876 sa.sa_family = AF_UNSPEC;
877 sa.sa_len = sizeof sa;
878 lwkt_serialize_enter(ifp->if_serializer);
879 (*ifp->if_output)(ifp, m, &sa, (struct rtentry *)0);
880 lwkt_serialize_exit(ifp->if_serializer);
886 * Free an arp entry. If the arp entry is actively referenced or represents
887 * a static entry we only clear it back to an unresolved state, otherwise
888 * we destroy the entry entirely.
890 * Note that static entries are created when route add ... -interface is used
891 * to create an interface route to a (direct) destination.
894 arptfree(struct llinfo_arp *la)
896 struct rtentry *rt = la->la_rt;
897 struct sockaddr_dl *sdl;
901 sdl = SDL(rt->rt_gateway);
903 ((rt->rt_refcnt > 0 && sdl->sdl_family == AF_LINK) ||
904 (rt->rt_flags & RTF_STATIC))) {
906 la->la_preempt = la->la_asked = 0;
907 rt->rt_flags &= ~RTF_REJECT;
910 rtrequest(RTM_DELETE, rt_key(rt), NULL, rt_mask(rt), 0, NULL);
914 * Lookup or enter a new address in arptab.
916 static struct llinfo_arp *
917 arplookup(in_addr_t addr, boolean_t create, boolean_t proxy)
920 struct sockaddr_inarp sin = { sizeof sin, AF_INET };
921 const char *why = NULL;
923 sin.sin_addr.s_addr = addr;
924 sin.sin_other = proxy ? SIN_PROXY : 0;
926 rt = rtlookup((struct sockaddr *)&sin);
928 rt = rtpurelookup((struct sockaddr *)&sin);
933 if (rt->rt_flags & RTF_GATEWAY)
934 why = "host is not on local network";
935 else if (!(rt->rt_flags & RTF_LLINFO))
936 why = "could not allocate llinfo";
937 else if (rt->rt_gateway->sa_family != AF_LINK)
938 why = "gateway route is not ours";
942 log(LOG_DEBUG, "arplookup %s failed: %s\n",
943 inet_ntoa(sin.sin_addr), why);
945 if (rt->rt_refcnt <= 0 && (rt->rt_flags & RTF_WASCLONED)) {
946 /* No references to this route. Purge it. */
947 rtrequest(RTM_DELETE, rt_key(rt), rt->rt_gateway,
948 rt_mask(rt), rt->rt_flags, NULL);
952 return (rt->rt_llinfo);
956 arp_ifinit(struct ifnet *ifp, struct ifaddr *ifa)
958 if (IA_SIN(ifa)->sin_addr.s_addr != INADDR_ANY)
959 arprequest(ifp, &IA_SIN(ifa)->sin_addr, &IA_SIN(ifa)->sin_addr,
961 ifa->ifa_rtrequest = arp_rtrequest;
962 ifa->ifa_flags |= RTF_CLONING;
968 LIST_INIT(&llinfo_arp);
969 netisr_register(NETISR_ARP, cpu0_portfn, arpintr);
972 SYSINIT(arp, SI_SUB_PROTO_DOMAIN, SI_ORDER_ANY, arp_init, 0);