<signal.h> has to and does provide pid_t, so we can also use it.
[dragonfly.git] / sys / netinet / if_ether.c
blobc6a4b5aaea139539ca53e7a482c3e7835b1b9c76
1 /*
2 * Copyright (c) 2004, 2005 The DragonFly Project. All rights reserved.
4 * This code is derived from software contributed to The DragonFly Project
5 * by Jeffrey M. Hsu.
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
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
30 * SUCH DAMAGE.
34 * Copyright (c) 1982, 1986, 1988, 1993
35 * The Regents of the University of California. All rights reserved.
37 * Redistribution and use in source and binary forms, with or without
38 * modification, are permitted provided that the following conditions
39 * are met:
40 * 1. Redistributions of source code must retain the above copyright
41 * notice, this list of conditions and the following disclaimer.
42 * 2. Redistributions in binary form must reproduce the above copyright
43 * notice, this list of conditions and the following disclaimer in the
44 * documentation and/or other materials provided with the distribution.
45 * 3. Neither the name of the University nor the names of its contributors
46 * may be used to endorse or promote products derived from this software
47 * without specific prior written permission.
49 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
50 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
51 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
52 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
53 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
54 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
55 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
56 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
57 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
58 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
59 * SUCH DAMAGE.
61 * @(#)if_ether.c 8.1 (Berkeley) 6/10/93
62 * $FreeBSD: src/sys/netinet/if_ether.c,v 1.64.2.23 2003/04/11 07:23:15 fjoe Exp $
66 * Ethernet address resolution protocol.
67 * TODO:
68 * add "inuse/lock" bit (or ref. count) along with valid bit
71 #include "opt_inet.h"
72 #include "opt_carp.h"
74 #include <sys/param.h>
75 #include <sys/kernel.h>
76 #include <sys/queue.h>
77 #include <sys/sysctl.h>
78 #include <sys/systm.h>
79 #include <sys/mbuf.h>
80 #include <sys/malloc.h>
81 #include <sys/socket.h>
82 #include <sys/syslog.h>
83 #include <sys/lock.h>
85 #include <net/if.h>
86 #include <net/if_dl.h>
87 #include <net/if_types.h>
88 #include <net/route.h>
89 #include <net/netisr.h>
90 #include <net/if_llc.h>
92 #include <netinet/in.h>
93 #include <netinet/in_var.h>
94 #include <netinet/if_ether.h>
96 #include <sys/thread2.h>
97 #include <sys/msgport2.h>
98 #include <net/netmsg2.h>
99 #include <net/netisr2.h>
100 #include <sys/mplock2.h>
102 #ifdef CARP
103 #include <netinet/ip_carp.h>
104 #endif
106 #define SIN(s) ((struct sockaddr_in *)s)
107 #define SDL(s) ((struct sockaddr_dl *)s)
109 MALLOC_DEFINE(M_ARP, "arp", "ARP");
111 SYSCTL_DECL(_net_link_ether);
112 SYSCTL_NODE(_net_link_ether, PF_INET, inet, CTLFLAG_RW, 0, "");
114 /* timer values */
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,
120 &arpt_prune, 0, "");
121 SYSCTL_INT(_net_link_ether_inet, OID_AUTO, max_age, CTLFLAG_RW,
122 &arpt_keep, 0, "");
123 SYSCTL_INT(_net_link_ether_inet, OID_AUTO, host_down_time, CTLFLAG_RW,
124 &arpt_down, 0, "");
126 #define rt_expire rt_rmx.rmx_expire
128 struct llinfo_arp {
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 int arp_maxtries = 5;
137 static int useloopback = 1; /* use loopback interface for local traffic */
138 static int arp_proxyall = 0;
139 static int arp_refresh = 60; /* refresh arp cache ~60 (not impl yet) */
140 static int arp_restricted_match = 0;
141 static int arp_ignore_probes = 1;
143 SYSCTL_INT(_net_link_ether_inet, OID_AUTO, maxtries, CTLFLAG_RW,
144 &arp_maxtries, 0, "ARP resolution attempts before returning error");
145 SYSCTL_INT(_net_link_ether_inet, OID_AUTO, useloopback, CTLFLAG_RW,
146 &useloopback, 0, "Use the loopback interface for local traffic");
147 SYSCTL_INT(_net_link_ether_inet, OID_AUTO, proxyall, CTLFLAG_RW,
148 &arp_proxyall, 0, "Enable proxy ARP for all suitable requests");
149 SYSCTL_INT(_net_link_ether_inet, OID_AUTO, restricted_match, CTLFLAG_RW,
150 &arp_restricted_match, 0, "Only match against the sender");
151 SYSCTL_INT(_net_link_ether_inet, OID_AUTO, refresh, CTLFLAG_RW,
152 &arp_refresh, 0, "Preemptively refresh the ARP");
153 SYSCTL_INT(_net_link_ether_inet, OID_AUTO, ignore_probes, CTLFLAG_RW,
154 &arp_ignore_probes, 0, "Ignore ARP probes");
156 static void arp_rtrequest(int, struct rtentry *);
157 static void arprequest(struct ifnet *, const struct in_addr *,
158 const struct in_addr *, const u_char *);
159 static void arprequest_async(struct ifnet *, const struct in_addr *,
160 const struct in_addr *, const u_char *);
161 static void arpintr(netmsg_t msg);
162 static void arptfree(struct llinfo_arp *);
163 static void arptimer(void *);
164 static struct llinfo_arp *
165 arplookup(in_addr_t, boolean_t, boolean_t, boolean_t);
166 #ifdef INET
167 static void in_arpinput(struct mbuf *);
168 static void in_arpreply(struct mbuf *m, in_addr_t, in_addr_t);
169 static void arp_update_msghandler(netmsg_t);
170 static void arp_reply_msghandler(netmsg_t);
171 #endif
173 struct arp_pcpu_data {
174 LIST_HEAD(, llinfo_arp) llinfo_list;
175 struct callout timer_ch;
176 struct netmsg_base timer_nmsg;
179 static struct arp_pcpu_data *arp_data[MAXCPU];
182 * Timeout routine. Age arp_tab entries periodically.
184 static void
185 arptimer_dispatch(netmsg_t nmsg)
187 struct arp_pcpu_data *ad = nmsg->lmsg.u.ms_resultp;
188 struct llinfo_arp *la, *nla;
190 ASSERT_NETISR_NCPUS(mycpuid);
192 /* Reply ASAP */
193 crit_enter();
194 netisr_replymsg(&nmsg->base, 0);
195 crit_exit();
197 LIST_FOREACH_MUTABLE(la, &ad->llinfo_list, la_le, nla) {
198 if (la->la_rt->rt_expire && la->la_rt->rt_expire <= time_uptime)
199 arptfree(la);
201 callout_reset(&ad->timer_ch, arpt_prune * hz, arptimer, &ad->timer_nmsg);
204 static void
205 arptimer(void *xnm)
207 struct netmsg_base *nm = xnm;
209 KKASSERT(mycpuid < netisr_ncpus);
211 crit_enter();
212 if (nm->lmsg.ms_flags & MSGF_DONE)
213 netisr_sendmsg_oncpu(nm);
214 crit_exit();
218 * Parallel to llc_rtrequest.
220 * Called after a route is successfully added to the tree to fix-up the
221 * route and initiate arp operations if required.
223 static void
224 arp_rtrequest(int req, struct rtentry *rt)
226 struct sockaddr *gate = rt->rt_gateway;
227 struct llinfo_arp *la = rt->rt_llinfo;
229 struct sockaddr_dl null_sdl = { sizeof null_sdl, AF_LINK };
231 if (rt->rt_flags & RTF_GATEWAY)
232 return;
234 switch (req) {
235 case RTM_ADD:
237 * XXX: If this is a manually added route to interface
238 * such as older version of routed or gated might provide,
239 * restore cloning bit.
241 if (!(rt->rt_flags & RTF_HOST) &&
242 SIN(rt_mask(rt))->sin_addr.s_addr != 0xffffffff)
243 rt->rt_flags |= RTF_CLONING;
244 if (rt->rt_flags & RTF_CLONING) {
246 * Case 1: This route should come from a route to iface.
248 rt_setgate(rt, rt_key(rt),
249 (struct sockaddr *)&null_sdl,
250 RTL_DONTREPORT);
251 gate = rt->rt_gateway;
252 SDL(gate)->sdl_type = rt->rt_ifp->if_type;
253 SDL(gate)->sdl_index = rt->rt_ifp->if_index;
254 rt->rt_expire = time_uptime;
255 break;
258 * Announce a new entry if requested, and only announce it
259 * once on cpu0.
261 if ((rt->rt_flags & RTF_ANNOUNCE) && mycpuid == 0) {
262 arprequest(rt->rt_ifp,
263 &SIN(rt_key(rt))->sin_addr,
264 &SIN(rt_key(rt))->sin_addr,
265 LLADDR(SDL(gate)));
267 /*FALLTHROUGH*/
268 case RTM_RESOLVE:
269 if (gate->sa_family != AF_LINK ||
270 gate->sa_len < sizeof(struct sockaddr_dl)) {
271 log(LOG_DEBUG, "arp_rtrequest: bad gateway value\n");
272 break;
274 SDL(gate)->sdl_type = rt->rt_ifp->if_type;
275 SDL(gate)->sdl_index = rt->rt_ifp->if_index;
276 if (la != NULL)
277 break; /* This happens on a route change */
279 * Case 2: This route may come from cloning, or a manual route
280 * add with a LL address.
282 R_Malloc(la, struct llinfo_arp *, sizeof *la);
283 rt->rt_llinfo = la;
284 if (la == NULL) {
285 log(LOG_DEBUG, "arp_rtrequest: malloc failed\n");
286 break;
288 bzero(la, sizeof *la);
289 la->la_rt = rt;
290 rt->rt_flags |= RTF_LLINFO;
291 LIST_INSERT_HEAD(&arp_data[mycpuid]->llinfo_list, la, la_le);
293 #ifdef INET
295 * This keeps the multicast addresses from showing up
296 * in `arp -a' listings as unresolved. It's not actually
297 * functional. Then the same for broadcast.
299 if (IN_MULTICAST(ntohl(SIN(rt_key(rt))->sin_addr.s_addr))) {
300 ETHER_MAP_IP_MULTICAST(&SIN(rt_key(rt))->sin_addr,
301 LLADDR(SDL(gate)));
302 SDL(gate)->sdl_alen = 6;
303 rt->rt_expire = 0;
305 if (in_broadcast(SIN(rt_key(rt))->sin_addr, rt->rt_ifp)) {
306 memcpy(LLADDR(SDL(gate)), rt->rt_ifp->if_broadcastaddr,
307 rt->rt_ifp->if_addrlen);
308 SDL(gate)->sdl_alen = rt->rt_ifp->if_addrlen;
309 rt->rt_expire = 0;
311 #endif
314 * This fixes up the routing interface for local addresses.
315 * The route is adjusted to point at lo0 and the expiration
316 * timer is disabled.
318 * NOTE: This prevents locally targetted traffic from going
319 * out the hardware interface, which is inefficient
320 * and might not work if the hardware cannot listen
321 * to its own transmitted packets. Setting
322 * net.link.ether.inet.useloopback to 0 will force
323 * packets for local addresses out the hardware (and
324 * it is expected to receive its own packet).
326 * XXX We should just be able to test RTF_LOCAL here instead
327 * of having to compare IPs.
329 if (SIN(rt_key(rt))->sin_addr.s_addr ==
330 (IA_SIN(rt->rt_ifa))->sin_addr.s_addr) {
331 rt->rt_expire = 0;
332 bcopy(IF_LLADDR(rt->rt_ifp), LLADDR(SDL(gate)),
333 SDL(gate)->sdl_alen = rt->rt_ifp->if_addrlen);
334 if (useloopback)
335 rt->rt_ifp = loif;
337 break;
339 case RTM_DELETE:
340 if (la == NULL)
341 break;
342 LIST_REMOVE(la, la_le);
343 rt->rt_llinfo = NULL;
344 rt->rt_flags &= ~RTF_LLINFO;
345 if (la->la_hold != NULL)
346 m_freem(la->la_hold);
347 Free(la);
348 break;
352 static struct mbuf *
353 arpreq_alloc(struct ifnet *ifp, const struct in_addr *sip,
354 const struct in_addr *tip, const u_char *enaddr)
356 struct mbuf *m;
357 struct arphdr *ah;
358 u_short ar_hrd;
360 if ((m = m_gethdr(M_NOWAIT, MT_DATA)) == NULL)
361 return NULL;
362 m->m_pkthdr.rcvif = NULL;
364 switch (ifp->if_type) {
365 case IFT_ETHER:
367 * This may not be correct for types not explicitly
368 * listed, but this is our best guess
370 default:
371 ar_hrd = htons(ARPHRD_ETHER);
373 m->m_len = arphdr_len2(ifp->if_addrlen, sizeof(struct in_addr));
374 m->m_pkthdr.len = m->m_len;
375 MH_ALIGN(m, m->m_len);
377 ah = mtod(m, struct arphdr *);
378 break;
381 ah->ar_hrd = ar_hrd;
382 ah->ar_pro = htons(ETHERTYPE_IP);
383 ah->ar_hln = ifp->if_addrlen; /* hardware address length */
384 ah->ar_pln = sizeof(struct in_addr); /* protocol address length */
385 ah->ar_op = htons(ARPOP_REQUEST);
386 memcpy(ar_sha(ah), enaddr, ah->ar_hln);
387 memset(ar_tha(ah), 0, ah->ar_hln);
388 memcpy(ar_spa(ah), sip, ah->ar_pln);
389 memcpy(ar_tpa(ah), tip, ah->ar_pln);
391 return m;
394 static void
395 arpreq_send(struct ifnet *ifp, struct mbuf *m)
397 struct sockaddr sa;
398 struct ether_header *eh;
400 ASSERT_NETISR_NCPUS(mycpuid);
402 switch (ifp->if_type) {
403 case IFT_ETHER:
405 * This may not be correct for types not explicitly
406 * listed, but this is our best guess
408 default:
409 eh = (struct ether_header *)sa.sa_data;
410 /* if_output() will not swap */
411 eh->ether_type = htons(ETHERTYPE_ARP);
412 memcpy(eh->ether_dhost, ifp->if_broadcastaddr, ifp->if_addrlen);
413 break;
416 sa.sa_family = AF_UNSPEC;
417 sa.sa_len = sizeof(sa);
418 ifp->if_output(ifp, m, &sa, NULL);
421 static void
422 arpreq_send_handler(netmsg_t msg)
424 struct mbuf *m = msg->packet.nm_packet;
425 struct ifnet *ifp = msg->lmsg.u.ms_resultp;
427 arpreq_send(ifp, m);
428 /* nmsg was embedded in the mbuf, do not reply! */
432 * Broadcast an ARP request. Caller specifies:
433 * - arp header source ip address
434 * - arp header target ip address
435 * - arp header source ethernet address
437 * NOTE: Caller MUST NOT hold ifp's serializer
439 static void
440 arprequest(struct ifnet *ifp, const struct in_addr *sip,
441 const struct in_addr *tip, const u_char *enaddr)
443 struct mbuf *m;
445 ASSERT_NETISR_NCPUS(mycpuid);
447 if (enaddr == NULL) {
448 if (ifp->if_bridge) {
449 enaddr = IF_LLADDR(ether_bridge_interface(ifp));
450 } else {
451 enaddr = IF_LLADDR(ifp);
455 m = arpreq_alloc(ifp, sip, tip, enaddr);
456 if (m == NULL)
457 return;
458 arpreq_send(ifp, m);
462 * Same as arprequest(), except:
463 * - Caller is allowed to hold ifp's serializer
464 * - Network output is done in protocol thead
466 static void
467 arprequest_async(struct ifnet *ifp, const struct in_addr *sip,
468 const struct in_addr *tip, const u_char *enaddr)
470 struct mbuf *m;
471 struct netmsg_packet *pmsg;
472 int cpu;
474 if (enaddr == NULL) {
475 if (ifp->if_bridge) {
476 enaddr = IF_LLADDR(ether_bridge_interface(ifp));
477 } else {
478 enaddr = IF_LLADDR(ifp);
481 m = arpreq_alloc(ifp, sip, tip, enaddr);
482 if (m == NULL)
483 return;
485 pmsg = &m->m_hdr.mh_netmsg;
486 netmsg_init(&pmsg->base, NULL, &netisr_apanic_rport,
487 0, arpreq_send_handler);
488 pmsg->nm_packet = m;
489 pmsg->base.lmsg.u.ms_resultp = ifp;
491 if (mycpuid < netisr_ncpus)
492 cpu = mycpuid;
493 else
494 cpu = 0;
495 lwkt_sendmsg(netisr_cpuport(cpu), &pmsg->base.lmsg);
499 * Resolve an IP address into an ethernet address. If success,
500 * desten is filled in. If there is no entry in arptab,
501 * set one up and broadcast a request for the IP address.
502 * Hold onto this mbuf and resend it once the address
503 * is finally resolved. A return value of 1 indicates
504 * that desten has been filled in and the packet should be sent
505 * normally; a 0 return indicates that the packet has been
506 * taken over here, either now or for later transmission.
509 arpresolve(struct ifnet *ifp, struct rtentry *rt0, struct mbuf *m,
510 struct sockaddr *dst, u_char *desten)
512 struct rtentry *rt = NULL;
513 struct llinfo_arp *la = NULL;
514 struct sockaddr_dl *sdl;
516 if (m->m_flags & M_BCAST) { /* broadcast */
517 memcpy(desten, ifp->if_broadcastaddr, ifp->if_addrlen);
518 return (1);
520 if (m->m_flags & M_MCAST) {/* multicast */
521 ETHER_MAP_IP_MULTICAST(&SIN(dst)->sin_addr, desten);
522 return (1);
524 if (rt0 != NULL) {
525 if (rt_llroute(dst, rt0, &rt) != 0) {
526 m_freem(m);
527 return 0;
529 la = rt->rt_llinfo;
531 if (la == NULL) {
532 la = arplookup(SIN(dst)->sin_addr.s_addr,
533 TRUE, RTL_REPORTMSG, FALSE);
534 if (la != NULL)
535 rt = la->la_rt;
537 if (la == NULL || rt == NULL) {
538 char addr[INET_ADDRSTRLEN];
540 log(LOG_DEBUG, "arpresolve: can't allocate llinfo for %s%s%s\n",
541 kinet_ntoa(SIN(dst)->sin_addr, addr), la ? "la" : " ",
542 rt ? "rt" : "");
543 m_freem(m);
544 return (0);
546 sdl = SDL(rt->rt_gateway);
548 * Check the address family and length is valid, the address
549 * is resolved; otherwise, try to resolve.
551 if ((rt->rt_expire == 0 || rt->rt_expire > time_uptime) &&
552 sdl->sdl_family == AF_LINK && sdl->sdl_alen != 0) {
554 * If entry has an expiry time and it is approaching,
555 * see if we need to send an ARP request within this
556 * arpt_down interval.
558 if ((rt->rt_expire != 0) &&
559 (time_uptime + la->la_preempt > rt->rt_expire)) {
560 arprequest(ifp,
561 &SIN(rt->rt_ifa->ifa_addr)->sin_addr,
562 &SIN(dst)->sin_addr,
563 NULL);
564 la->la_preempt--;
567 bcopy(LLADDR(sdl), desten, sdl->sdl_alen);
568 return 1;
571 * If ARP is disabled or static on this interface, stop.
572 * XXX
573 * Probably should not allocate empty llinfo struct if we are
574 * not going to be sending out an arp request.
576 if (ifp->if_flags & (IFF_NOARP | IFF_STATICARP)) {
577 m_freem(m);
578 return (0);
581 * There is an arptab entry, but no ethernet address
582 * response yet. Replace the held mbuf with this
583 * latest one.
585 if (la->la_hold != NULL)
586 m_freem(la->la_hold);
587 la->la_hold = m;
588 if (rt->rt_expire || ((rt->rt_flags & RTF_STATIC) && !sdl->sdl_alen)) {
589 rt->rt_flags &= ~RTF_REJECT;
590 if (la->la_asked == 0 || rt->rt_expire != time_uptime) {
591 rt->rt_expire = time_uptime;
592 if (la->la_asked++ < arp_maxtries) {
593 arprequest(ifp,
594 &SIN(rt->rt_ifa->ifa_addr)->sin_addr,
595 &SIN(dst)->sin_addr,
596 NULL);
597 } else {
598 rt->rt_flags |= RTF_REJECT;
599 rt->rt_expire += arpt_down;
600 la->la_asked = 0;
601 la->la_preempt = arp_maxtries;
605 return (0);
609 * Common length and type checks are done here,
610 * then the protocol-specific routine is called.
612 static void
613 arpintr(netmsg_t msg)
615 struct mbuf *m = msg->packet.nm_packet;
616 struct arphdr *ar;
617 u_short ar_hrd;
618 char hexstr[6];
620 if (m->m_len < sizeof(struct arphdr) &&
621 (m = m_pullup(m, sizeof(struct arphdr))) == NULL) {
622 log(LOG_ERR, "arp: runt packet -- m_pullup failed\n");
623 return;
625 ar = mtod(m, struct arphdr *);
627 ar_hrd = ntohs(ar->ar_hrd);
628 if (ar_hrd != ARPHRD_ETHER && ar_hrd != ARPHRD_IEEE802) {
629 hexncpy((unsigned char *)&ar->ar_hrd, 2, hexstr, 5, NULL);
630 log(LOG_ERR, "arp: unknown hardware address format (0x%s)\n",
631 hexstr);
632 m_freem(m);
633 return;
636 if (m->m_pkthdr.len < arphdr_len(ar)) {
637 if ((m = m_pullup(m, arphdr_len(ar))) == NULL) {
638 log(LOG_ERR, "arp: runt packet\n");
639 return;
641 ar = mtod(m, struct arphdr *);
644 switch (ntohs(ar->ar_pro)) {
645 #ifdef INET
646 case ETHERTYPE_IP:
647 in_arpinput(m);
648 return;
649 #endif
651 m_freem(m);
652 /* msg was embedded in the mbuf, do not reply! */
655 #ifdef INET
657 * ARP for Internet protocols on 10 Mb/s Ethernet.
658 * Algorithm is that given in RFC 826.
659 * In addition, a sanity check is performed on the sender
660 * protocol address, to catch impersonators.
661 * We no longer handle negotiations for use of trailer protocol:
662 * Formerly, ARP replied for protocol type ETHERTYPE_TRAIL sent
663 * along with IP replies if we wanted trailers sent to us,
664 * and also sent them in response to IP replies.
665 * This allowed either end to announce the desire to receive
666 * trailer packets.
667 * We no longer reply to requests for ETHERTYPE_TRAIL protocol either,
668 * but formerly didn't normally send requests.
671 static int log_arp_wrong_iface = 1;
672 static int log_arp_movements = 1;
673 static int log_arp_permanent_modify = 1;
674 static int log_arp_creation_failure = 1;
676 SYSCTL_INT(_net_link_ether_inet, OID_AUTO, log_arp_wrong_iface, CTLFLAG_RW,
677 &log_arp_wrong_iface, 0,
678 "Log arp packets arriving on the wrong interface");
679 SYSCTL_INT(_net_link_ether_inet, OID_AUTO, log_arp_movements, CTLFLAG_RW,
680 &log_arp_movements, 0,
681 "Log arp replies from MACs different than the one in the cache");
682 SYSCTL_INT(_net_link_ether_inet, OID_AUTO, log_arp_permanent_modify, CTLFLAG_RW,
683 &log_arp_permanent_modify, 0,
684 "Log arp replies from MACs different than the one "
685 "in the permanent arp entry");
686 SYSCTL_INT(_net_link_ether_inet, OID_AUTO, log_arp_creation_failure, CTLFLAG_RW,
687 &log_arp_creation_failure, 0, "Log arp creation failure");
690 * Returns non-zero if the routine updated anything.
692 static int
693 arp_update_oncpu(struct mbuf *m, in_addr_t saddr, boolean_t create,
694 boolean_t generate_report, boolean_t dologging)
696 struct arphdr *ah = mtod(m, struct arphdr *);
697 struct ifnet *ifp = m->m_pkthdr.rcvif;
698 struct llinfo_arp *la;
699 struct sockaddr_dl *sdl;
700 struct rtentry *rt;
701 char hexstr[2][64];
702 char sbuf[INET_ADDRSTRLEN];
703 int changed = create;
705 KASSERT(curthread->td_type == TD_TYPE_NETISR,
706 ("arp update not in netisr"));
708 la = arplookup(saddr, create, generate_report, FALSE);
709 if (la && (rt = la->la_rt) && (sdl = SDL(rt->rt_gateway))) {
710 struct in_addr isaddr = { saddr };
713 * Normally arps coming in on the wrong interface are ignored,
714 * but if we are bridging and the two interfaces belong to
715 * the same bridge, or one is a member of the bridge which
716 * is the other, then it isn't an error.
718 if (rt->rt_ifp != ifp) {
720 * (1) ifp and rt_ifp both members of same bridge
721 * (2) rt_ifp member of bridge ifp
722 * (3) ifp member of bridge rt_ifp
724 * Always replace rt_ifp with the bridge ifc.
726 struct ifnet *nifp;
728 if (ifp->if_bridge &&
729 rt->rt_ifp->if_bridge == ifp->if_bridge) {
730 nifp = ether_bridge_interface(ifp);
731 } else if (rt->rt_ifp->if_bridge &&
732 ether_bridge_interface(rt->rt_ifp) == ifp) {
733 nifp = ifp;
734 } else if (ifp->if_bridge &&
735 ether_bridge_interface(ifp) == rt->rt_ifp) {
736 nifp = rt->rt_ifp;
737 } else {
738 nifp = NULL;
741 if ((log_arp_wrong_iface == 1 && nifp == NULL) ||
742 log_arp_wrong_iface == 2) {
743 hexncpy((u_char *)ar_sha(ah), ifp->if_addrlen,
744 hexstr[0], HEX_NCPYLEN(ifp->if_addrlen), ":");
745 log(LOG_ERR,
746 "arp: %s is on %s "
747 "but got reply from %s on %s\n",
748 kinet_ntoa(isaddr, sbuf),
749 rt->rt_ifp->if_xname, hexstr[0],
750 ifp->if_xname);
752 if (nifp == NULL)
753 return 0;
756 * nifp is our man! Replace rt_ifp and adjust
757 * the sdl.
759 ifp = rt->rt_ifp = nifp;
760 if (sdl->sdl_type != ifp->if_type) {
761 sdl->sdl_type = ifp->if_type;
762 changed = 1;
764 if (sdl->sdl_index != ifp->if_index) {
765 sdl->sdl_index = ifp->if_index;
766 changed = 1;
769 if (sdl->sdl_alen &&
770 bcmp(ar_sha(ah), LLADDR(sdl), sdl->sdl_alen)) {
771 changed = 1;
772 if (rt->rt_expire != 0) {
773 if (dologging && log_arp_movements) {
774 hexncpy((u_char *)LLADDR(sdl), ifp->if_addrlen,
775 hexstr[0], HEX_NCPYLEN(ifp->if_addrlen), ":");
776 hexncpy((u_char *)ar_sha(ah), ifp->if_addrlen,
777 hexstr[1], HEX_NCPYLEN(ifp->if_addrlen), ":");
778 log(LOG_INFO,
779 "arp: %s moved from %s to %s on %s\n",
780 kinet_ntoa(isaddr, sbuf), hexstr[0], hexstr[1],
781 ifp->if_xname);
783 } else {
784 if (dologging && log_arp_permanent_modify) {
785 hexncpy((u_char *)ar_sha(ah), ifp->if_addrlen,
786 hexstr[0], HEX_NCPYLEN(ifp->if_addrlen), ":");
787 log(LOG_ERR,
788 "arp: %s attempts to modify "
789 "permanent entry for %s on %s\n",
790 hexstr[0], kinet_ntoa(isaddr, sbuf), ifp->if_xname);
792 return changed;
796 * sanity check for the address length.
797 * XXX this does not work for protocols with variable address
798 * length. -is
800 if (dologging && sdl->sdl_alen && sdl->sdl_alen != ah->ar_hln) {
801 hexncpy((u_char *)ar_sha(ah), ifp->if_addrlen,
802 hexstr[0], HEX_NCPYLEN(ifp->if_addrlen), ":");
803 log(LOG_WARNING,
804 "arp from %s: new addr len %d, was %d",
805 hexstr[0], ah->ar_hln, sdl->sdl_alen);
807 if (ifp->if_addrlen != ah->ar_hln) {
808 if (dologging) {
809 hexncpy((u_char *)ar_sha(ah), ifp->if_addrlen,
810 hexstr[0], HEX_NCPYLEN(ifp->if_addrlen), ":");
811 log(LOG_WARNING,
812 "arp from %s: addr len: new %d, i/f %d "
813 "(ignored)", hexstr[0],
814 ah->ar_hln, ifp->if_addrlen);
816 return changed;
818 memcpy(LLADDR(sdl), ar_sha(ah), sdl->sdl_alen = ah->ar_hln);
819 if (rt->rt_expire != 0) {
820 if (rt->rt_expire != time_uptime + arpt_keep &&
821 rt->rt_expire != time_uptime + arpt_keep - 1) {
822 rt->rt_expire = time_uptime + arpt_keep;
823 changed = 1;
826 if (rt->rt_flags & RTF_REJECT) {
827 rt->rt_flags &= ~RTF_REJECT;
828 changed = 1;
830 if (la->la_asked != 0) {
831 la->la_asked = 0;
832 changed = 1;
834 if (la->la_preempt != arp_maxtries) {
835 la->la_preempt = arp_maxtries;
836 changed = 1;
840 * This particular cpu might have been holding an mbuf
841 * pending ARP resolution. If so, transmit the mbuf now.
843 if (la->la_hold != NULL) {
844 struct mbuf *m = la->la_hold;
846 la->la_hold = NULL;
847 m_adj(m, sizeof(struct ether_header));
848 ifp->if_output(ifp, m, rt_key(rt), rt);
849 changed = 1;
852 return changed;
856 * Called from arpintr() - this routine is run from a single cpu.
858 static void
859 in_arpinput(struct mbuf *m)
861 struct arphdr *ah;
862 struct ifnet *ifp = m->m_pkthdr.rcvif;
863 struct ifaddr_container *ifac;
864 struct in_ifaddr_container *iac;
865 struct in_ifaddr *ia = NULL;
866 struct in_addr isaddr, itaddr, myaddr;
867 uint8_t *enaddr = NULL;
868 int req_len;
869 int changed;
870 char hexstr[64], sbuf[INET_ADDRSTRLEN];
872 req_len = arphdr_len2(ifp->if_addrlen, sizeof(struct in_addr));
873 if (m->m_len < req_len && (m = m_pullup(m, req_len)) == NULL) {
874 log(LOG_ERR, "in_arp: runt packet -- m_pullup failed\n");
875 return;
878 ah = mtod(m, struct arphdr *);
879 memcpy(&isaddr, ar_spa(ah), sizeof isaddr);
880 memcpy(&itaddr, ar_tpa(ah), sizeof itaddr);
883 * Check both target and sender IP addresses:
885 * If we receive the packet on the interface owning the address,
886 * then accept the address.
888 * For a bridge, we accept the address if the receive interface and
889 * the interface owning the address are on the same bridge, and
890 * use the bridge MAC as the is-at response. The bridge will be
891 * responsible for handling the packet.
893 * (0) Check target IP against CARP IPs
895 #ifdef CARP
896 LIST_FOREACH(iac, INADDR_HASH(itaddr.s_addr), ia_hash) {
897 int is_match = 0, is_parent = 0;
899 ia = iac->ia;
901 /* Skip all ia's which don't match */
902 if (itaddr.s_addr != ia->ia_addr.sin_addr.s_addr)
903 continue;
905 if (ia->ia_ifp->if_type != IFT_CARP)
906 continue;
908 if (carp_parent(ia->ia_ifp) == ifp)
909 is_parent = 1;
910 if (is_parent || ia->ia_ifp == ifp)
911 is_match = carp_iamatch(ia);
913 if (is_match) {
914 if (is_parent) {
916 * The parent interface will also receive
917 * the ethernet broadcast packets, e.g. ARP
918 * REQUEST, so if we could find a CARP
919 * interface of the parent that could match
920 * the target IP address, we then drop the
921 * packets, which is delieverd to us through
922 * the parent interface.
924 m_freem(m);
925 return;
927 goto match;
930 #endif /* CARP */
933 * (1) Check target IP against our local IPs
935 LIST_FOREACH(iac, INADDR_HASH(itaddr.s_addr), ia_hash) {
936 ia = iac->ia;
938 /* Skip all ia's which don't match */
939 if (itaddr.s_addr != ia->ia_addr.sin_addr.s_addr)
940 continue;
942 #ifdef CARP
943 /* CARP interfaces are checked in (0) */
944 if (ia->ia_ifp->if_type == IFT_CARP)
945 continue;
946 #endif
948 if (ifp->if_bridge && ia->ia_ifp &&
949 ifp->if_bridge == ia->ia_ifp->if_bridge) {
950 ifp = ether_bridge_interface(ifp);
951 goto match;
953 if (ia->ia_ifp && ia->ia_ifp->if_bridge &&
954 ether_bridge_interface(ia->ia_ifp) == ifp) {
955 goto match;
957 if (ifp->if_bridge && ether_bridge_interface(ifp) ==
958 ia->ia_ifp) {
959 goto match;
961 if (ia->ia_ifp == ifp) {
962 goto match;
967 * (2) Check sender IP against our local IPs
969 LIST_FOREACH(iac, INADDR_HASH(isaddr.s_addr), ia_hash) {
970 ia = iac->ia;
972 /* Skip all ia's which don't match */
973 if (isaddr.s_addr != ia->ia_addr.sin_addr.s_addr)
974 continue;
976 if (ifp->if_bridge && ia->ia_ifp &&
977 ifp->if_bridge == ia->ia_ifp->if_bridge) {
978 ifp = ether_bridge_interface(ifp);
979 goto match;
981 if (ia->ia_ifp && ia->ia_ifp->if_bridge &&
982 ether_bridge_interface(ia->ia_ifp) == ifp) {
983 goto match;
985 if (ifp->if_bridge && ether_bridge_interface(ifp) ==
986 ia->ia_ifp) {
987 goto match;
990 if (ia->ia_ifp == ifp)
991 goto match;
995 * No match, use the first inet address on the receive interface
996 * as a dummy address for the rest of the function.
998 TAILQ_FOREACH(ifac, &ifp->if_addrheads[mycpuid], ifa_link) {
999 struct ifaddr *ifa = ifac->ifa;
1001 if (ifa->ifa_addr && ifa->ifa_addr->sa_family == AF_INET) {
1002 ia = ifatoia(ifa);
1003 goto match;
1008 * If we got here, we didn't find any suitable interface,
1009 * so drop the packet.
1011 m_freem(m);
1012 return;
1014 match:
1015 if (!enaddr)
1016 enaddr = (uint8_t *)IF_LLADDR(ifp);
1017 myaddr = ia->ia_addr.sin_addr;
1018 if (!bcmp(ar_sha(ah), enaddr, ifp->if_addrlen)) {
1019 m_freem(m); /* it's from me, ignore it. */
1020 return;
1022 if (!bcmp(ar_sha(ah), ifp->if_broadcastaddr, ifp->if_addrlen)) {
1023 log(LOG_ERR,
1024 "arp: link address is broadcast for IP address %s!\n",
1025 kinet_ntoa(isaddr, sbuf));
1026 m_freem(m);
1027 return;
1029 if (isaddr.s_addr == myaddr.s_addr && myaddr.s_addr != 0) {
1030 hexncpy((u_char *)ar_sha(ah), ifp->if_addrlen,
1031 hexstr, HEX_NCPYLEN(ifp->if_addrlen), ":");
1032 log(LOG_ERR,
1033 "arp: %s is using my IP address %s!\n",
1034 hexstr, kinet_ntoa(isaddr, sbuf));
1035 itaddr = myaddr;
1036 goto reply;
1038 if (ifp->if_flags & IFF_STATICARP)
1039 goto reply;
1042 * When arp_restricted_match is true and the ARP response is not
1043 * specifically targetted to me, ignore it. Otherwise the entry
1044 * timeout may be updated for an old MAC.
1046 if (arp_restricted_match && itaddr.s_addr != myaddr.s_addr) {
1047 m_freem(m);
1048 return;
1052 * Update all CPU's routing tables with this ARP packet.
1054 * However, we only need to generate rtmsg on CPU0.
1056 ASSERT_NETISR0;
1057 changed = arp_update_oncpu(m, isaddr.s_addr,
1058 itaddr.s_addr == myaddr.s_addr,
1059 RTL_REPORTMSG, TRUE);
1061 if (netisr_ncpus > 1 && changed) {
1062 struct netmsg_inarp *msg = &m->m_hdr.mh_arpmsg;
1064 netmsg_init(&msg->base, NULL, &netisr_apanic_rport,
1065 0, arp_update_msghandler);
1066 msg->m = m;
1067 msg->saddr = isaddr.s_addr;
1068 msg->taddr = itaddr.s_addr;
1069 msg->myaddr = myaddr.s_addr;
1070 lwkt_sendmsg(netisr_cpuport(1), &msg->base.lmsg);
1071 } else {
1072 goto reply;
1076 * Just return here; after all CPUs's routing tables are
1077 * properly updated by this ARP packet, an ARP reply will
1078 * be generated if appropriate.
1080 return;
1081 reply:
1082 in_arpreply(m, itaddr.s_addr, myaddr.s_addr);
1085 static void
1086 arp_reply_msghandler(netmsg_t msg)
1088 struct netmsg_inarp *rmsg = (struct netmsg_inarp *)msg;
1090 in_arpreply(rmsg->m, rmsg->taddr, rmsg->myaddr);
1091 /* Don't reply this netmsg; netmsg_inarp is embedded in mbuf */
1094 static void
1095 arp_update_msghandler(netmsg_t msg)
1097 struct netmsg_inarp *rmsg = (struct netmsg_inarp *)msg;
1098 int nextcpu;
1100 ASSERT_NETISR_NCPUS(mycpuid);
1103 * This message handler will be called on all of the APs;
1104 * no need to generate rtmsg on them.
1106 KASSERT(mycpuid > 0, ("arp update msg on cpu%d", mycpuid));
1107 arp_update_oncpu(rmsg->m, rmsg->saddr,
1108 rmsg->taddr == rmsg->myaddr,
1109 RTL_DONTREPORT, FALSE);
1111 nextcpu = mycpuid + 1;
1112 if (nextcpu < netisr_ncpus) {
1113 lwkt_forwardmsg(netisr_cpuport(nextcpu), &rmsg->base.lmsg);
1114 } else {
1115 struct mbuf *m = rmsg->m;
1116 in_addr_t saddr = rmsg->saddr;
1117 in_addr_t taddr = rmsg->taddr;
1118 in_addr_t myaddr = rmsg->myaddr;
1121 * Dispatch this mbuf to netisr0 to perform ARP reply,
1122 * if appropriate.
1123 * NOTE: netmsg_inarp is embedded in this mbuf.
1125 netmsg_init(&rmsg->base, NULL, &netisr_apanic_rport,
1126 0, arp_reply_msghandler);
1127 rmsg->m = m;
1128 rmsg->saddr = saddr;
1129 rmsg->taddr = taddr;
1130 rmsg->myaddr = myaddr;
1131 lwkt_sendmsg(netisr_cpuport(0), &rmsg->base.lmsg);
1136 * Reply to an arp request
1138 static void
1139 in_arpreply(struct mbuf *m, in_addr_t taddr, in_addr_t myaddr)
1141 struct ifnet *ifp = m->m_pkthdr.rcvif;
1142 const uint8_t *enaddr;
1143 struct arphdr *ah;
1144 struct sockaddr sa;
1145 struct ether_header *eh;
1147 ASSERT_NETISR0;
1149 ah = mtod(m, struct arphdr *);
1150 if (ntohs(ah->ar_op) != ARPOP_REQUEST) {
1151 m_freem(m);
1152 return;
1155 enaddr = (const uint8_t *)IF_LLADDR(ifp);
1156 if (taddr == myaddr) {
1157 /* I am the target */
1158 memcpy(ar_tha(ah), ar_sha(ah), ah->ar_hln);
1159 memcpy(ar_sha(ah), enaddr, ah->ar_hln);
1160 } else {
1161 struct llinfo_arp *la;
1162 struct rtentry *rt;
1164 la = arplookup(taddr, FALSE, RTL_DONTREPORT, SIN_PROXY);
1165 if (la == NULL) {
1166 struct sockaddr_in sin;
1167 #ifdef DEBUG_PROXY
1168 char tbuf[INET_ADDRSTRLEN];
1169 #endif
1171 if (!arp_proxyall) {
1172 m_freem(m);
1173 return;
1176 bzero(&sin, sizeof sin);
1177 sin.sin_family = AF_INET;
1178 sin.sin_len = sizeof sin;
1179 sin.sin_addr.s_addr = taddr;
1181 rt = rtpurelookup((struct sockaddr *)&sin);
1182 if (rt == NULL) {
1183 m_freem(m);
1184 return;
1186 --rt->rt_refcnt;
1189 * Don't send proxies for nodes on the same interface
1190 * as this one came out of, or we'll get into a fight
1191 * over who claims what Ether address.
1193 * If the rt entry is associated with a bridge, we
1194 * count it as the 'same' interface if ifp is
1195 * associated with the bridge.
1197 if (rt->rt_ifp == ifp || rt->rt_ifp == ifp->if_bridge) {
1198 m_freem(m);
1199 return;
1201 memcpy(ar_tha(ah), ar_sha(ah), ah->ar_hln);
1202 memcpy(ar_sha(ah), enaddr, ah->ar_hln);
1203 #ifdef DEBUG_PROXY
1204 kprintf("arp: proxying for %s\n",
1205 kinet_ntoa(itaddr, tbuf));
1206 #endif
1207 } else {
1208 struct sockaddr_dl *sdl;
1210 rt = la->la_rt;
1211 memcpy(ar_tha(ah), ar_sha(ah), ah->ar_hln);
1212 sdl = SDL(rt->rt_gateway);
1213 memcpy(ar_sha(ah), LLADDR(sdl), ah->ar_hln);
1217 memcpy(ar_tpa(ah), ar_spa(ah), ah->ar_pln);
1218 memcpy(ar_spa(ah), &taddr, ah->ar_pln);
1219 ah->ar_op = htons(ARPOP_REPLY);
1220 ah->ar_pro = htons(ETHERTYPE_IP); /* let's be sure! */
1221 switch (ifp->if_type) {
1222 case IFT_ETHER:
1224 * May not be correct for types not explictly
1225 * listed, but it is our best guess.
1227 default:
1228 eh = (struct ether_header *)sa.sa_data;
1229 memcpy(eh->ether_dhost, ar_tha(ah), sizeof eh->ether_dhost);
1230 eh->ether_type = htons(ETHERTYPE_ARP);
1231 break;
1233 sa.sa_family = AF_UNSPEC;
1234 sa.sa_len = sizeof sa;
1235 ifp->if_output(ifp, m, &sa, NULL);
1238 #endif /* INET */
1241 * Free an arp entry. If the arp entry is actively referenced or represents
1242 * a static entry we only clear it back to an unresolved state, otherwise
1243 * we destroy the entry entirely.
1245 * Note that static entries are created when route add ... -interface is used
1246 * to create an interface route to a (direct) destination.
1248 static void
1249 arptfree(struct llinfo_arp *la)
1251 struct rtentry *rt = la->la_rt;
1252 struct sockaddr_dl *sdl;
1254 if (rt == NULL)
1255 panic("arptfree");
1256 sdl = SDL(rt->rt_gateway);
1257 if (sdl != NULL &&
1258 ((rt->rt_refcnt > 0 && sdl->sdl_family == AF_LINK) ||
1259 (rt->rt_flags & RTF_STATIC))) {
1260 sdl->sdl_alen = 0;
1261 la->la_preempt = la->la_asked = 0;
1262 rt->rt_flags &= ~RTF_REJECT;
1263 return;
1265 rtrequest(RTM_DELETE, rt_key(rt), NULL, rt_mask(rt), 0, NULL);
1269 * Lookup or enter a new address in arptab.
1271 static struct llinfo_arp *
1272 arplookup(in_addr_t addr, boolean_t create, boolean_t generate_report,
1273 boolean_t proxy)
1275 struct rtentry *rt;
1276 struct sockaddr_inarp sin = { sizeof sin, AF_INET };
1277 const char *why = NULL;
1279 /* Check ARP probes, e.g. from Cisco switches. */
1280 if (addr == INADDR_ANY && arp_ignore_probes)
1281 return (NULL);
1283 sin.sin_addr.s_addr = addr;
1284 sin.sin_other = proxy ? SIN_PROXY : 0;
1285 if (create) {
1286 rt = _rtlookup((struct sockaddr *)&sin,
1287 generate_report, RTL_DOCLONE);
1288 } else {
1289 rt = rtpurelookup((struct sockaddr *)&sin);
1291 if (rt == NULL)
1292 return (NULL);
1293 rt->rt_refcnt--;
1295 if (rt->rt_flags & RTF_GATEWAY)
1296 why = "host is not on local network";
1297 else if (!(rt->rt_flags & RTF_LLINFO))
1298 why = "could not allocate llinfo";
1299 else if (rt->rt_gateway->sa_family != AF_LINK)
1300 why = "gateway route is not ours";
1302 if (why) {
1303 if (create && log_arp_creation_failure) {
1304 char abuf[INET_ADDRSTRLEN];
1306 log(LOG_DEBUG, "arplookup %s failed: %s\n",
1307 kinet_ntoa(sin.sin_addr, abuf), why);
1309 if (rt->rt_refcnt <= 0 && (rt->rt_flags & RTF_WASCLONED)) {
1310 /* No references to this route. Purge it. */
1311 rtrequest(RTM_DELETE, rt_key(rt), rt->rt_gateway,
1312 rt_mask(rt), rt->rt_flags, NULL);
1314 return (NULL);
1316 return (rt->rt_llinfo);
1319 void
1320 arp_ifinit(struct ifnet *ifp, struct ifaddr *ifa)
1322 ifa->ifa_rtrequest = arp_rtrequest;
1323 ifa->ifa_flags |= RTF_CLONING;
1326 void
1327 arp_gratuitous(struct ifnet *ifp, struct ifaddr *ifa)
1329 if (IA_SIN(ifa)->sin_addr.s_addr != INADDR_ANY) {
1330 if (IN_NETISR_NCPUS(mycpuid)) {
1331 arprequest(ifp, &IA_SIN(ifa)->sin_addr,
1332 &IA_SIN(ifa)->sin_addr, NULL);
1333 } else {
1334 arprequest_async(ifp, &IA_SIN(ifa)->sin_addr,
1335 &IA_SIN(ifa)->sin_addr, NULL);
1340 static void
1341 arp_ifaddr(void *arg __unused, struct ifnet *ifp,
1342 enum ifaddr_event event, struct ifaddr *ifa)
1344 if (ifa->ifa_rtrequest != arp_rtrequest) /* XXX need a generic way */
1345 return;
1346 if (ifa->ifa_addr->sa_family != AF_INET)
1347 return;
1348 if (event == IFADDR_EVENT_DELETE)
1349 return;
1352 * - CARP interfaces will take care of gratuitous ARP themselves.
1353 * - If we are the CARP interface's parent, don't send gratuitous
1354 * ARP to avoid unnecessary confusion.
1356 #ifdef CARP
1357 if (ifp->if_type != IFT_CARP && ifp->if_carp == NULL)
1358 #endif
1360 arp_gratuitous(ifp, ifa);
1364 static void
1365 arp_init_dispatch(netmsg_t nm)
1367 struct arp_pcpu_data *ad;
1369 ASSERT_NETISR_NCPUS(mycpuid);
1371 ad = kmalloc(sizeof(*ad), M_ARP, M_WAITOK | M_ZERO);
1373 LIST_INIT(&ad->llinfo_list);
1374 callout_init_mp(&ad->timer_ch);
1375 netmsg_init(&ad->timer_nmsg, NULL, &netisr_adone_rport,
1376 MSGF_PRIORITY, arptimer_dispatch);
1377 ad->timer_nmsg.lmsg.u.ms_resultp = ad;
1379 arp_data[mycpuid] = ad;
1381 callout_reset(&ad->timer_ch, hz, arptimer, &ad->timer_nmsg);
1383 netisr_forwardmsg(&nm->base, mycpuid + 1);
1386 static void
1387 arp_init(void)
1389 struct netmsg_base nm;
1391 netmsg_init(&nm, NULL, &curthread->td_msgport, 0, arp_init_dispatch);
1392 netisr_domsg_global(&nm);
1394 netisr_register(NETISR_ARP, arpintr, NULL);
1396 EVENTHANDLER_REGISTER(ifaddr_event, arp_ifaddr, NULL,
1397 EVENTHANDLER_PRI_LAST);
1399 SYSINIT(arp, SI_SUB_PROTO_DOMAIN, SI_ORDER_ANY, arp_init, 0);