FreeBSD/Linux Kernel Cross Reference
sys/netinet/if_arp.c
1 /* $NetBSD: if_arp.c,v 1.94 2003/09/24 06:52:47 itojun Exp $ */
2
3 /*-
4 * Copyright (c) 1998, 2000 The NetBSD Foundation, Inc.
5 * All rights reserved.
6 *
7 * This code is derived from software contributed to The NetBSD Foundation
8 * by Public Access Networks Corporation ("Panix"). It was developed under
9 * contract to Panix by Eric Haszlakiewicz and Thor Lancelot Simon.
10 *
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
13 * are met:
14 * 1. Redistributions of source code must retain the above copyright
15 * notice, this list of conditions and the following disclaimer.
16 * 2. Redistributions in binary form must reproduce the above copyright
17 * notice, this list of conditions and the following disclaimer in the
18 * documentation and/or other materials provided with the distribution.
19 * 3. All advertising materials mentioning features or use of this software
20 * must display the following acknowledgement:
21 * This product includes software developed by the NetBSD
22 * Foundation, Inc. and its contributors.
23 * 4. Neither the name of The NetBSD Foundation nor the names of its
24 * contributors may be used to endorse or promote products derived
25 * from this software without specific prior written permission.
26 *
27 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
28 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
29 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
30 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
31 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
32 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
33 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
34 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
35 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
36 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
37 * POSSIBILITY OF SUCH DAMAGE.
38 */
39
40 /*
41 * Copyright (c) 1982, 1986, 1988, 1993
42 * The Regents of the University of California. All rights reserved.
43 *
44 * Redistribution and use in source and binary forms, with or without
45 * modification, are permitted provided that the following conditions
46 * are met:
47 * 1. Redistributions of source code must retain the above copyright
48 * notice, this list of conditions and the following disclaimer.
49 * 2. Redistributions in binary form must reproduce the above copyright
50 * notice, this list of conditions and the following disclaimer in the
51 * documentation and/or other materials provided with the distribution.
52 * 3. Neither the name of the University nor the names of its contributors
53 * may be used to endorse or promote products derived from this software
54 * without specific prior written permission.
55 *
56 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
57 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
58 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
59 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
60 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
61 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
62 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
63 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
64 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
65 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
66 * SUCH DAMAGE.
67 *
68 * @(#)if_ether.c 8.2 (Berkeley) 9/26/94
69 */
70
71 /*
72 * Ethernet address resolution protocol.
73 * TODO:
74 * add "inuse/lock" bit (or ref. count) along with valid bit
75 */
76
77 #include <sys/cdefs.h>
78 __KERNEL_RCSID(0, "$NetBSD: if_arp.c,v 1.94 2003/09/24 06:52:47 itojun Exp $");
79
80 #include "opt_ddb.h"
81 #include "opt_inet.h"
82
83 #ifdef INET
84
85 #include "bridge.h"
86
87 #include <sys/param.h>
88 #include <sys/systm.h>
89 #include <sys/callout.h>
90 #include <sys/malloc.h>
91 #include <sys/mbuf.h>
92 #include <sys/socket.h>
93 #include <sys/time.h>
94 #include <sys/kernel.h>
95 #include <sys/errno.h>
96 #include <sys/ioctl.h>
97 #include <sys/syslog.h>
98 #include <sys/proc.h>
99 #include <sys/protosw.h>
100 #include <sys/domain.h>
101
102 #include <net/ethertypes.h>
103 #include <net/if.h>
104 #include <net/if_dl.h>
105 #include <net/if_token.h>
106 #include <net/if_types.h>
107 #include <net/route.h>
108
109 #include <netinet/in.h>
110 #include <netinet/in_systm.h>
111 #include <netinet/in_var.h>
112 #include <netinet/ip.h>
113 #include <netinet/if_inarp.h>
114
115 #include "loop.h"
116 #include "arc.h"
117 #if NARC > 0
118 #include <net/if_arc.h>
119 #endif
120 #include "fddi.h"
121 #if NFDDI > 0
122 #include <net/if_fddi.h>
123 #endif
124 #include "token.h"
125
126 #define SIN(s) ((struct sockaddr_in *)s)
127 #define SDL(s) ((struct sockaddr_dl *)s)
128 #define SRP(s) ((struct sockaddr_inarp *)s)
129
130 /*
131 * ARP trailer negotiation. Trailer protocol is not IP specific,
132 * but ARP request/response use IP addresses.
133 */
134 #define ETHERTYPE_IPTRAILERS ETHERTYPE_TRAIL
135
136 /* timer values */
137 int arpt_prune = (5*60*1); /* walk list every 5 minutes */
138 int arpt_keep = (20*60); /* once resolved, good for 20 more minutes */
139 int arpt_down = 20; /* once declared down, don't send for 20 secs */
140 #define rt_expire rt_rmx.rmx_expire
141
142 extern struct domain arpdomain;
143
144 static void arprequest __P((struct ifnet *,
145 struct in_addr *, struct in_addr *, u_int8_t *));
146 static void arptfree __P((struct llinfo_arp *));
147 static void arptimer __P((void *));
148 static struct llinfo_arp *arplookup __P((struct mbuf *, struct in_addr *,
149 int, int));
150 static void in_arpinput __P((struct mbuf *));
151
152 #if NLOOP > 0
153 extern struct ifnet loif[NLOOP];
154 #endif
155 LIST_HEAD(, llinfo_arp) llinfo_arp;
156 struct ifqueue arpintrq = {0, 0, 0, 50};
157 int arp_inuse, arp_allocated, arp_intimer;
158 int arp_maxtries = 5;
159 int useloopback = 1; /* use loopback interface for local traffic */
160 int arpinit_done = 0;
161
162 struct arpstat arpstat;
163 struct callout arptimer_ch;
164
165
166 /* revarp state */
167 static struct in_addr myip, srv_ip;
168 static int myip_initialized = 0;
169 static int revarp_in_progress = 0;
170 static struct ifnet *myip_ifp = NULL;
171
172 #ifdef DDB
173 static void db_print_sa __P((struct sockaddr *));
174 static void db_print_ifa __P((struct ifaddr *));
175 static void db_print_llinfo __P((caddr_t));
176 static int db_show_radix_node __P((struct radix_node *, void *));
177 #endif
178
179 /*
180 * this should be elsewhere.
181 */
182
183 static char *
184 lla_snprintf __P((u_int8_t *, int));
185
186 static char *
187 lla_snprintf(adrp, len)
188 u_int8_t *adrp;
189 int len;
190 {
191 #define NUMBUFS 3
192 static char buf[NUMBUFS][16*3];
193 static int bnum = 0;
194 static const char hexdigits[] = {
195 '','1','2','3','4','5','6','7',
196 '8','9','a','b','c','d','e','f'
197 };
198
199 int i;
200 char *p;
201
202 p = buf[bnum];
203
204 *p++ = hexdigits[(*adrp)>>4];
205 *p++ = hexdigits[(*adrp++)&0xf];
206
207 for (i=1; i<len && i<16; i++) {
208 *p++ = ':';
209 *p++ = hexdigits[(*adrp)>>4];
210 *p++ = hexdigits[(*adrp++)&0xf];
211 }
212
213 *p = 0;
214 p = buf[bnum];
215 bnum = (bnum + 1) % NUMBUFS;
216 return p;
217 }
218
219 struct protosw arpsw[] = {
220 { 0, 0, 0, 0,
221 0, 0, 0, 0,
222 0,
223 0, 0, 0, arp_drain,
224 }
225 };
226
227
228 struct domain arpdomain =
229 { PF_ARP, "arp", 0, 0, 0,
230 arpsw, &arpsw[sizeof(arpsw)/sizeof(arpsw[0])]
231 };
232
233 /*
234 * ARP table locking.
235 *
236 * to prevent lossage vs. the arp_drain routine (which may be called at
237 * any time, including in a device driver context), we do two things:
238 *
239 * 1) manipulation of la->la_hold is done at splnet() (for all of
240 * about two instructions).
241 *
242 * 2) manipulation of the arp table's linked list is done under the
243 * protection of the ARP_LOCK; if arp_drain() or arptimer is called
244 * while the arp table is locked, we punt and try again later.
245 */
246
247 static int arp_locked;
248 static __inline int arp_lock_try __P((int));
249 static __inline void arp_unlock __P((void));
250
251 static __inline int
252 arp_lock_try(int recurse)
253 {
254 int s;
255
256 /*
257 * Use splvm() -- we're blocking things that would cause
258 * mbuf allocation.
259 */
260 s = splvm();
261 if (!recurse && arp_locked) {
262 splx(s);
263 return (0);
264 }
265 arp_locked++;
266 splx(s);
267 return (1);
268 }
269
270 static __inline void
271 arp_unlock()
272 {
273 int s;
274
275 s = splvm();
276 arp_locked--;
277 splx(s);
278 }
279
280 #ifdef DIAGNOSTIC
281 #define ARP_LOCK(recurse) \
282 do { \
283 if (arp_lock_try(recurse) == 0) { \
284 printf("%s:%d: arp already locked\n", __FILE__, __LINE__); \
285 panic("arp_lock"); \
286 } \
287 } while (/*CONSTCOND*/ 0)
288 #define ARP_LOCK_CHECK() \
289 do { \
290 if (arp_locked == 0) { \
291 printf("%s:%d: arp lock not held\n", __FILE__, __LINE__); \
292 panic("arp lock check"); \
293 } \
294 } while (/*CONSTCOND*/ 0)
295 #else
296 #define ARP_LOCK(x) (void) arp_lock_try(x)
297 #define ARP_LOCK_CHECK() /* nothing */
298 #endif
299
300 #define ARP_UNLOCK() arp_unlock()
301
302 /*
303 * ARP protocol drain routine. Called when memory is in short supply.
304 * Called at splvm();
305 */
306
307 void
308 arp_drain()
309 {
310 struct llinfo_arp *la, *nla;
311 int count = 0;
312 struct mbuf *mold;
313
314 if (arp_lock_try(0) == 0) {
315 printf("arp_drain: locked; punting\n");
316 return;
317 }
318
319 for (la = LIST_FIRST(&llinfo_arp); la != 0; la = nla) {
320 nla = LIST_NEXT(la, la_list);
321
322 mold = la->la_hold;
323 la->la_hold = 0;
324
325 if (mold) {
326 m_freem(mold);
327 count++;
328 }
329 }
330 ARP_UNLOCK();
331 arpstat.as_dfrdropped += count;
332 }
333
334
335 /*
336 * Timeout routine. Age arp_tab entries periodically.
337 */
338 /* ARGSUSED */
339 static void
340 arptimer(arg)
341 void *arg;
342 {
343 int s;
344 struct llinfo_arp *la, *nla;
345
346 s = splsoftnet();
347
348 if (arp_lock_try(0) == 0) {
349 /* get it later.. */
350 splx(s);
351 return;
352 }
353
354 callout_reset(&arptimer_ch, arpt_prune * hz, arptimer, NULL);
355 for (la = LIST_FIRST(&llinfo_arp); la != 0; la = nla) {
356 struct rtentry *rt = la->la_rt;
357
358 nla = LIST_NEXT(la, la_list);
359 if (rt->rt_expire && rt->rt_expire <= time.tv_sec)
360 arptfree(la); /* timer has expired; clear */
361 }
362
363 ARP_UNLOCK();
364
365 splx(s);
366 }
367
368 /*
369 * Parallel to llc_rtrequest.
370 */
371 void
372 arp_rtrequest(req, rt, info)
373 int req;
374 struct rtentry *rt;
375 struct rt_addrinfo *info;
376 {
377 struct sockaddr *gate = rt->rt_gateway;
378 struct llinfo_arp *la = (struct llinfo_arp *)rt->rt_llinfo;
379 static struct sockaddr_dl null_sdl = {sizeof(null_sdl), AF_LINK};
380 size_t allocsize;
381 struct mbuf *mold;
382 int s;
383 struct in_ifaddr *ia;
384 struct ifaddr *ifa;
385
386 if (!arpinit_done) {
387 arpinit_done = 1;
388 /*
389 * We generate expiration times from time.tv_sec
390 * so avoid accidently creating permanent routes.
391 */
392 if (time.tv_sec == 0) {
393 time.tv_sec++;
394 }
395 callout_init(&arptimer_ch);
396 callout_reset(&arptimer_ch, hz, arptimer, NULL);
397 }
398
399 if ((rt->rt_flags & RTF_GATEWAY) != 0) {
400 if (req != RTM_ADD)
401 return;
402
403 /*
404 * linklayers with particular link MTU limitation.
405 */
406 switch(rt->rt_ifp->if_type) {
407 #if NFDDI > 0
408 case IFT_FDDI:
409 if (rt->rt_ifp->if_mtu > FDDIIPMTU)
410 rt->rt_rmx.rmx_mtu = FDDIIPMTU;
411 break;
412 #endif
413 #if NARC > 0
414 case IFT_ARCNET:
415 {
416 int arcipifmtu;
417
418 if (rt->rt_ifp->if_flags & IFF_LINK0)
419 arcipifmtu = arc_ipmtu;
420 else
421 arcipifmtu = ARCMTU;
422 if (rt->rt_ifp->if_mtu > arcipifmtu)
423 rt->rt_rmx.rmx_mtu = arcipifmtu;
424 break;
425 }
426 #endif
427 }
428 return;
429 }
430
431 ARP_LOCK(1); /* we may already be locked here. */
432
433 switch (req) {
434
435 case RTM_ADD:
436 /*
437 * XXX: If this is a manually added route to interface
438 * such as older version of routed or gated might provide,
439 * restore cloning bit.
440 */
441 if ((rt->rt_flags & RTF_HOST) == 0 &&
442 SIN(rt_mask(rt))->sin_addr.s_addr != 0xffffffff)
443 rt->rt_flags |= RTF_CLONING;
444 if (rt->rt_flags & RTF_CLONING) {
445 /*
446 * Case 1: This route should come from a route to iface.
447 */
448 rt_setgate(rt, rt_key(rt),
449 (struct sockaddr *)&null_sdl);
450 gate = rt->rt_gateway;
451 SDL(gate)->sdl_type = rt->rt_ifp->if_type;
452 SDL(gate)->sdl_index = rt->rt_ifp->if_index;
453 /*
454 * Give this route an expiration time, even though
455 * it's a "permanent" route, so that routes cloned
456 * from it do not need their expiration time set.
457 */
458 rt->rt_expire = time.tv_sec;
459 /*
460 * linklayers with particular link MTU limitation.
461 */
462 switch (rt->rt_ifp->if_type) {
463 #if NFDDI > 0
464 case IFT_FDDI:
465 if ((rt->rt_rmx.rmx_locks & RTV_MTU) == 0 &&
466 (rt->rt_rmx.rmx_mtu > FDDIIPMTU ||
467 (rt->rt_rmx.rmx_mtu == 0 &&
468 rt->rt_ifp->if_mtu > FDDIIPMTU)))
469 rt->rt_rmx.rmx_mtu = FDDIIPMTU;
470 break;
471 #endif
472 #if NARC > 0
473 case IFT_ARCNET:
474 {
475 int arcipifmtu;
476 if (rt->rt_ifp->if_flags & IFF_LINK0)
477 arcipifmtu = arc_ipmtu;
478 else
479 arcipifmtu = ARCMTU;
480
481 if ((rt->rt_rmx.rmx_locks & RTV_MTU) == 0 &&
482 (rt->rt_rmx.rmx_mtu > arcipifmtu ||
483 (rt->rt_rmx.rmx_mtu == 0 &&
484 rt->rt_ifp->if_mtu > arcipifmtu)))
485 rt->rt_rmx.rmx_mtu = arcipifmtu;
486 break;
487 }
488 #endif
489 }
490 break;
491 }
492 /* Announce a new entry if requested. */
493 if (rt->rt_flags & RTF_ANNOUNCE)
494 arprequest(rt->rt_ifp,
495 &SIN(rt_key(rt))->sin_addr,
496 &SIN(rt_key(rt))->sin_addr,
497 (u_char *)LLADDR(SDL(gate)));
498 /*FALLTHROUGH*/
499 case RTM_RESOLVE:
500 if (gate->sa_family != AF_LINK ||
501 gate->sa_len < sizeof(null_sdl)) {
502 log(LOG_DEBUG, "arp_rtrequest: bad gateway value\n");
503 break;
504 }
505 SDL(gate)->sdl_type = rt->rt_ifp->if_type;
506 SDL(gate)->sdl_index = rt->rt_ifp->if_index;
507 if (la != 0)
508 break; /* This happens on a route change */
509 /*
510 * Case 2: This route may come from cloning, or a manual route
511 * add with a LL address.
512 */
513 switch (SDL(gate)->sdl_type) {
514 #if NTOKEN > 0
515 case IFT_ISO88025:
516 allocsize = sizeof(*la) + sizeof(struct token_rif);
517 break;
518 #endif /* NTOKEN > 0 */
519 default:
520 allocsize = sizeof(*la);
521 }
522 R_Malloc(la, struct llinfo_arp *, allocsize);
523 rt->rt_llinfo = (caddr_t)la;
524 if (la == 0) {
525 log(LOG_DEBUG, "arp_rtrequest: malloc failed\n");
526 break;
527 }
528 arp_inuse++, arp_allocated++;
529 Bzero(la, allocsize);
530 la->la_rt = rt;
531 rt->rt_flags |= RTF_LLINFO;
532 LIST_INSERT_HEAD(&llinfo_arp, la, la_list);
533
534 INADDR_TO_IA(SIN(rt_key(rt))->sin_addr, ia);
535 while (ia && ia->ia_ifp != rt->rt_ifp)
536 NEXT_IA_WITH_SAME_ADDR(ia);
537 if (ia) {
538 /*
539 * This test used to be
540 * if (loif.if_flags & IFF_UP)
541 * It allowed local traffic to be forced through
542 * the hardware by configuring the loopback down.
543 * However, it causes problems during network
544 * configuration for boards that can't receive
545 * packets they send. It is now necessary to clear
546 * "useloopback" and remove the route to force
547 * traffic out to the hardware.
548 *
549 * In 4.4BSD, the above "if" statement checked
550 * rt->rt_ifa against rt_key(rt). It was changed
551 * to the current form so that we can provide a
552 * better support for multiple IPv4 addresses on a
553 * interface.
554 */
555 rt->rt_expire = 0;
556 Bcopy(LLADDR(rt->rt_ifp->if_sadl),
557 LLADDR(SDL(gate)),
558 SDL(gate)->sdl_alen = rt->rt_ifp->if_addrlen);
559 #if NLOOP > 0
560 if (useloopback)
561 rt->rt_ifp = &loif[0];
562 #endif
563 /*
564 * make sure to set rt->rt_ifa to the interface
565 * address we are using, otherwise we will have trouble
566 * with source address selection.
567 */
568 ifa = &ia->ia_ifa;
569 if (ifa != rt->rt_ifa) {
570 IFAFREE(rt->rt_ifa);
571 IFAREF(ifa);
572 rt->rt_ifa = ifa;
573 }
574 }
575 break;
576
577 case RTM_DELETE:
578 if (la == 0)
579 break;
580 arp_inuse--;
581 LIST_REMOVE(la, la_list);
582 rt->rt_llinfo = 0;
583 rt->rt_flags &= ~RTF_LLINFO;
584
585 s = splnet();
586 mold = la->la_hold;
587 la->la_hold = 0;
588 splx(s);
589
590 if (mold)
591 m_freem(mold);
592
593 Free((caddr_t)la);
594 }
595 ARP_UNLOCK();
596 }
597
598 /*
599 * Broadcast an ARP request. Caller specifies:
600 * - arp header source ip address
601 * - arp header target ip address
602 * - arp header source ethernet address
603 */
604 static void
605 arprequest(ifp, sip, tip, enaddr)
606 struct ifnet *ifp;
607 struct in_addr *sip, *tip;
608 u_int8_t *enaddr;
609 {
610 struct mbuf *m;
611 struct arphdr *ah;
612 struct sockaddr sa;
613
614 if ((m = m_gethdr(M_DONTWAIT, MT_DATA)) == NULL)
615 return;
616 MCLAIM(m, &arpdomain.dom_mowner);
617 switch (ifp->if_type) {
618 case IFT_IEEE1394:
619 m->m_len = sizeof(*ah) + 2 * sizeof(struct in_addr) +
620 ifp->if_addrlen;
621 break;
622 default:
623 m->m_len = sizeof(*ah) + 2 * sizeof(struct in_addr) +
624 2 * ifp->if_addrlen;
625 break;
626 }
627 m->m_pkthdr.len = m->m_len;
628 MH_ALIGN(m, m->m_len);
629 ah = mtod(m, struct arphdr *);
630 bzero((caddr_t)ah, m->m_len);
631 switch (ifp->if_type) {
632 case IFT_IEEE1394: /* RFC2734 */
633 /* fill it now for ar_tpa computation */
634 ah->ar_hrd = htons(ARPHRD_IEEE1394);
635 break;
636 default:
637 /* ifp->if_output will fill ar_hrd */
638 break;
639 }
640 ah->ar_pro = htons(ETHERTYPE_IP);
641 ah->ar_hln = ifp->if_addrlen; /* hardware address length */
642 ah->ar_pln = sizeof(struct in_addr); /* protocol address length */
643 ah->ar_op = htons(ARPOP_REQUEST);
644 bcopy((caddr_t)enaddr, (caddr_t)ar_sha(ah), ah->ar_hln);
645 bcopy((caddr_t)sip, (caddr_t)ar_spa(ah), ah->ar_pln);
646 bcopy((caddr_t)tip, (caddr_t)ar_tpa(ah), ah->ar_pln);
647 sa.sa_family = AF_ARP;
648 sa.sa_len = 2;
649 m->m_flags |= M_BCAST;
650 arpstat.as_sndtotal++;
651 arpstat.as_sndrequest++;
652 (*ifp->if_output)(ifp, m, &sa, (struct rtentry *)0);
653 }
654
655 /*
656 * Resolve an IP address into an ethernet address. If success,
657 * desten is filled in. If there is no entry in arptab,
658 * set one up and broadcast a request for the IP address.
659 * Hold onto this mbuf and resend it once the address
660 * is finally resolved. A return value of 1 indicates
661 * that desten has been filled in and the packet should be sent
662 * normally; a 0 return indicates that the packet has been
663 * taken over here, either now or for later transmission.
664 */
665 int
666 arpresolve(ifp, rt, m, dst, desten)
667 struct ifnet *ifp;
668 struct rtentry *rt;
669 struct mbuf *m;
670 struct sockaddr *dst;
671 u_char *desten;
672 {
673 struct llinfo_arp *la;
674 struct sockaddr_dl *sdl;
675 struct mbuf *mold;
676 int s;
677
678 if (rt)
679 la = (struct llinfo_arp *)rt->rt_llinfo;
680 else {
681 if ((la = arplookup(m, &SIN(dst)->sin_addr, 1, 0)) != NULL)
682 rt = la->la_rt;
683 }
684 if (la == 0 || rt == 0) {
685 arpstat.as_allocfail++;
686 log(LOG_DEBUG,
687 "arpresolve: can't allocate llinfo on %s for %s\n",
688 ifp->if_xname, in_fmtaddr(SIN(dst)->sin_addr));
689 m_freem(m);
690 return (0);
691 }
692 sdl = SDL(rt->rt_gateway);
693 /*
694 * Check the address family and length is valid, the address
695 * is resolved; otherwise, try to resolve.
696 */
697 if ((rt->rt_expire == 0 || rt->rt_expire > time.tv_sec) &&
698 sdl->sdl_family == AF_LINK && sdl->sdl_alen != 0) {
699 bcopy(LLADDR(sdl), desten,
700 min(sdl->sdl_alen, ifp->if_addrlen));
701 return 1;
702 }
703 /*
704 * There is an arptab entry, but no ethernet address
705 * response yet. Replace the held mbuf with this
706 * latest one.
707 */
708
709 arpstat.as_dfrtotal++;
710 s = splnet();
711 mold = la->la_hold;
712 la->la_hold = m;
713 splx(s);
714
715 if (mold) {
716 arpstat.as_dfrdropped++;
717 m_freem(mold);
718 }
719
720 /*
721 * Re-send the ARP request when appropriate.
722 */
723 #ifdef DIAGNOSTIC
724 if (rt->rt_expire == 0) {
725 /* This should never happen. (Should it? -gwr) */
726 printf("arpresolve: unresolved and rt_expire == 0\n");
727 /* Set expiration time to now (expired). */
728 rt->rt_expire = time.tv_sec;
729 }
730 #endif
731 if (rt->rt_expire) {
732 rt->rt_flags &= ~RTF_REJECT;
733 if (la->la_asked == 0 || rt->rt_expire != time.tv_sec) {
734 rt->rt_expire = time.tv_sec;
735 if (la->la_asked++ < arp_maxtries)
736 arprequest(ifp,
737 &SIN(rt->rt_ifa->ifa_addr)->sin_addr,
738 &SIN(dst)->sin_addr,
739 LLADDR(ifp->if_sadl));
740 else {
741 rt->rt_flags |= RTF_REJECT;
742 rt->rt_expire += arpt_down;
743 la->la_asked = 0;
744 }
745 }
746 }
747 return (0);
748 }
749
750 /*
751 * Common length and type checks are done here,
752 * then the protocol-specific routine is called.
753 */
754 void
755 arpintr()
756 {
757 struct mbuf *m;
758 struct arphdr *ar;
759 int s;
760 int arplen;
761
762 while (arpintrq.ifq_head) {
763 s = splnet();
764 IF_DEQUEUE(&arpintrq, m);
765 splx(s);
766 if (m == 0 || (m->m_flags & M_PKTHDR) == 0)
767 panic("arpintr");
768
769 MCLAIM(m, &arpdomain.dom_mowner);
770 arpstat.as_rcvtotal++;
771
772 /*
773 * First, make sure we have at least struct arphdr.
774 */
775 if (m->m_len < sizeof(struct arphdr) ||
776 (ar = mtod(m, struct arphdr *)) == NULL)
777 goto badlen;
778
779 switch (m->m_pkthdr.rcvif->if_type) {
780 case IFT_IEEE1394:
781 arplen = sizeof(struct arphdr) +
782 ar->ar_hln + 2 * ar->ar_pln;
783 break;
784 default:
785 arplen = sizeof(struct arphdr) +
786 2 * ar->ar_hln + 2 * ar->ar_pln;
787 break;
788 }
789
790 if (/* XXX ntohs(ar->ar_hrd) == ARPHRD_ETHER && */
791 m->m_len >= arplen)
792 switch (ntohs(ar->ar_pro)) {
793 case ETHERTYPE_IP:
794 case ETHERTYPE_IPTRAILERS:
795 in_arpinput(m);
796 continue;
797 default:
798 arpstat.as_rcvbadproto++;
799 }
800 else {
801 badlen:
802 arpstat.as_rcvbadlen++;
803 }
804 m_freem(m);
805 }
806 }
807
808 /*
809 * ARP for Internet protocols on 10 Mb/s Ethernet.
810 * Algorithm is that given in RFC 826.
811 * In addition, a sanity check is performed on the sender
812 * protocol address, to catch impersonators.
813 * We no longer handle negotiations for use of trailer protocol:
814 * Formerly, ARP replied for protocol type ETHERTYPE_TRAIL sent
815 * along with IP replies if we wanted trailers sent to us,
816 * and also sent them in response to IP replies.
817 * This allowed either end to announce the desire to receive
818 * trailer packets.
819 * We no longer reply to requests for ETHERTYPE_TRAIL protocol either,
820 * but formerly didn't normally send requests.
821 */
822 static void
823 in_arpinput(m)
824 struct mbuf *m;
825 {
826 struct arphdr *ah;
827 struct ifnet *ifp = m->m_pkthdr.rcvif;
828 struct llinfo_arp *la = 0;
829 struct rtentry *rt;
830 struct in_ifaddr *ia;
831 #if NBRIDGE > 0
832 struct in_ifaddr *bridge_ia = NULL;
833 #endif
834 struct sockaddr_dl *sdl;
835 struct sockaddr sa;
836 struct in_addr isaddr, itaddr, myaddr;
837 int op;
838 struct mbuf *mold;
839 int s;
840
841 ah = mtod(m, struct arphdr *);
842 op = ntohs(ah->ar_op);
843
844 /*
845 * Fix up ah->ar_hrd if necessary, before using ar_tha() or
846 * ar_tpa().
847 */
848 switch (ifp->if_type) {
849 case IFT_IEEE1394:
850 if (ntohs(ah->ar_hrd) == ARPHRD_IEEE1394)
851 ;
852 else {
853 /* XXX this is to make sure we compute ar_tha right */
854 /* XXX check ar_hrd more strictly? */
855 ah->ar_hrd = htons(ARPHRD_IEEE1394);
856 }
857 break;
858 default:
859 /* XXX check ar_hrd? */
860 break;
861 }
862
863 bcopy((caddr_t)ar_spa(ah), (caddr_t)&isaddr, sizeof (isaddr));
864 bcopy((caddr_t)ar_tpa(ah), (caddr_t)&itaddr, sizeof (itaddr));
865
866 if (m->m_flags & (M_BCAST|M_MCAST))
867 arpstat.as_rcvmcast++;
868
869 /*
870 * If the target IP address is zero, ignore the packet.
871 * This prevents the code below from tring to answer
872 * when we are using IP address zero (booting).
873 */
874 if (in_nullhost(itaddr)) {
875 arpstat.as_rcvzerotpa++;
876 goto out;
877 }
878
879 /*
880 * If the source IP address is zero, this is most likely a
881 * confused host trying to use IP address zero. (Windoze?)
882 * XXX: Should we bother trying to reply to these?
883 */
884 if (in_nullhost(isaddr)) {
885 arpstat.as_rcvzerospa++;
886 goto out;
887 }
888
889 /*
890 * Search for a matching interface address
891 * or any address on the interface to use
892 * as a dummy address in the rest of this function
893 */
894 INADDR_TO_IA(itaddr, ia);
895 while (ia != NULL) {
896 if (ia->ia_ifp == m->m_pkthdr.rcvif)
897 break;
898
899 #if NBRIDGE > 0
900 /*
901 * If the interface we received the packet on
902 * is part of a bridge, check to see if we need
903 * to "bridge" the packet to ourselves at this
904 * layer. Note we still prefer a perfect match,
905 * but allow this weaker match if necessary.
906 */
907 if (m->m_pkthdr.rcvif->if_bridge != NULL &&
908 m->m_pkthdr.rcvif->if_bridge == ia->ia_ifp->if_bridge)
909 bridge_ia = ia;
910 #endif /* NBRIDGE > 0 */
911
912 NEXT_IA_WITH_SAME_ADDR(ia);
913 }
914
915 #if NBRIDGE > 0
916 if (ia == NULL && bridge_ia != NULL) {
917 ia = bridge_ia;
918 ifp = bridge_ia->ia_ifp;
919 }
920 #endif
921
922 if (ia == NULL) {
923 INADDR_TO_IA(isaddr, ia);
924 while ((ia != NULL) && ia->ia_ifp != m->m_pkthdr.rcvif)
925 NEXT_IA_WITH_SAME_ADDR(ia);
926
927 if (ia == NULL) {
928 IFP_TO_IA(ifp, ia);
929 if (ia == NULL) {
930 arpstat.as_rcvnoint++;
931 goto out;
932 }
933 }
934 }
935
936 myaddr = ia->ia_addr.sin_addr;
937
938 /* XXX checks for bridge case? */
939 if (!bcmp((caddr_t)ar_sha(ah), LLADDR(ifp->if_sadl),
940 ifp->if_addrlen)) {
941 arpstat.as_rcvlocalsha++;
942 goto out; /* it's from me, ignore it. */
943 }
944
945 /* XXX checks for bridge case? */
946 if (!bcmp((caddr_t)ar_sha(ah), (caddr_t)ifp->if_broadcastaddr,
947 ifp->if_addrlen)) {
948 arpstat.as_rcvbcastsha++;
949 log(LOG_ERR,
950 "%s: arp: link address is broadcast for IP address %s!\n",
951 ifp->if_xname, in_fmtaddr(isaddr));
952 goto out;
953 }
954
955 if (in_hosteq(isaddr, myaddr)) {
956 arpstat.as_rcvlocalspa++;
957 log(LOG_ERR,
958 "duplicate IP address %s sent from link address %s\n",
959 in_fmtaddr(isaddr), lla_snprintf(ar_sha(ah), ah->ar_hln));
960 itaddr = myaddr;
961 goto reply;
962 }
963 la = arplookup(m, &isaddr, in_hosteq(itaddr, myaddr), 0);
964 if (la && (rt = la->la_rt) && (sdl = SDL(rt->rt_gateway))) {
965 if (sdl->sdl_alen &&
966 bcmp((caddr_t)ar_sha(ah), LLADDR(sdl), sdl->sdl_alen)) {
967 if (rt->rt_flags & RTF_STATIC) {
968 arpstat.as_rcvoverperm++;
969 log(LOG_INFO,
970 "%s tried to overwrite permanent arp info"
971 " for %s\n",
972 lla_snprintf(ar_sha(ah), ah->ar_hln),
973 in_fmtaddr(isaddr));
974 goto out;
975 } else if (rt->rt_ifp != ifp) {
976 arpstat.as_rcvoverint++;
977 log(LOG_INFO,
978 "%s on %s tried to overwrite "
979 "arp info for %s on %s\n",
980 lla_snprintf(ar_sha(ah), ah->ar_hln),
981 ifp->if_xname, in_fmtaddr(isaddr),
982 rt->rt_ifp->if_xname);
983 goto out;
984 } else {
985 arpstat.as_rcvover++;
986 log(LOG_INFO,
987 "arp info overwritten for %s by %s\n",
988 in_fmtaddr(isaddr),
989 lla_snprintf(ar_sha(ah), ah->ar_hln));
990 }
991 }
992 /*
993 * sanity check for the address length.
994 * XXX this does not work for protocols with variable address
995 * length. -is
996 */
997 if (sdl->sdl_alen &&
998 sdl->sdl_alen != ah->ar_hln) {
999 arpstat.as_rcvlenchg++;
1000 log(LOG_WARNING,
1001 "arp from %s: new addr len %d, was %d",
1002 in_fmtaddr(isaddr), ah->ar_hln, sdl->sdl_alen);
1003 }
1004 if (ifp->if_addrlen != ah->ar_hln) {
1005 arpstat.as_rcvbadlen++;
1006 log(LOG_WARNING,
1007 "arp from %s: addr len: new %d, i/f %d (ignored)",
1008 in_fmtaddr(isaddr), ah->ar_hln,
1009 ifp->if_addrlen);
1010 goto reply;
1011 }
1012 #if NTOKEN > 0
1013 /*
1014 * XXX uses m_data and assumes the complete answer including
1015 * XXX token-ring headers is in the same buf
1016 */
1017 if (ifp->if_type == IFT_ISO88025) {
1018 struct token_header *trh;
1019
1020 trh = (struct token_header *)M_TRHSTART(m);
1021 if (trh->token_shost[0] & TOKEN_RI_PRESENT) {
1022 struct token_rif *rif;
1023 size_t riflen;
1024
1025 rif = TOKEN_RIF(trh);
1026 riflen = (ntohs(rif->tr_rcf) &
1027 TOKEN_RCF_LEN_MASK) >> 8;
1028
1029 if (riflen > 2 &&
1030 riflen < sizeof(struct token_rif) &&
1031 (riflen & 1) == 0) {
1032 rif->tr_rcf ^= htons(TOKEN_RCF_DIRECTION);
1033 rif->tr_rcf &= htons(~TOKEN_RCF_BROADCAST_MASK);
1034 bcopy(rif, TOKEN_RIF(la), riflen);
1035 }
1036 }
1037 }
1038 #endif /* NTOKEN > 0 */
1039 bcopy((caddr_t)ar_sha(ah), LLADDR(sdl),
1040 sdl->sdl_alen = ah->ar_hln);
1041 if (rt->rt_expire)
1042 rt->rt_expire = time.tv_sec + arpt_keep;
1043 rt->rt_flags &= ~RTF_REJECT;
1044 la->la_asked = 0;
1045
1046 s = splnet();
1047 mold = la->la_hold;
1048 la->la_hold = 0;
1049 splx(s);
1050
1051 if (mold) {
1052 arpstat.as_dfrsent++;
1053 (*ifp->if_output)(ifp, mold, rt_key(rt), rt);
1054 }
1055 }
1056 reply:
1057 if (op != ARPOP_REQUEST) {
1058 if (op == ARPOP_REPLY)
1059 arpstat.as_rcvreply++;
1060 out:
1061 m_freem(m);
1062 return;
1063 }
1064 arpstat.as_rcvrequest++;
1065 if (in_hosteq(itaddr, myaddr)) {
1066 /* I am the target */
1067 if (ar_tha(ah))
1068 bcopy((caddr_t)ar_sha(ah), (caddr_t)ar_tha(ah),
1069 ah->ar_hln);
1070 bcopy(LLADDR(ifp->if_sadl), (caddr_t)ar_sha(ah), ah->ar_hln);
1071 } else {
1072 la = arplookup(m, &itaddr, 0, SIN_PROXY);
1073 if (la == 0)
1074 goto out;
1075 rt = la->la_rt;
1076 if (ar_tha(ah))
1077 bcopy((caddr_t)ar_sha(ah), (caddr_t)ar_tha(ah),
1078 ah->ar_hln);
1079 sdl = SDL(rt->rt_gateway);
1080 bcopy(LLADDR(sdl), (caddr_t)ar_sha(ah), ah->ar_hln);
1081 }
1082
1083 bcopy((caddr_t)ar_spa(ah), (caddr_t)ar_tpa(ah), ah->ar_pln);
1084 bcopy((caddr_t)&itaddr, (caddr_t)ar_spa(ah), ah->ar_pln);
1085 ah->ar_op = htons(ARPOP_REPLY);
1086 ah->ar_pro = htons(ETHERTYPE_IP); /* let's be sure! */
1087 switch (ifp->if_type) {
1088 case IFT_IEEE1394:
1089 /*
1090 * ieee1394 arp reply is broadcast
1091 */
1092 m->m_flags &= ~M_MCAST;
1093 m->m_flags |= M_BCAST;
1094 m->m_len = sizeof(*ah) + (2 * ah->ar_pln) + ah->ar_hln;
1095 break;
1096
1097 default:
1098 m->m_flags &= ~(M_BCAST|M_MCAST); /* never reply by broadcast */
1099 m->m_len = sizeof(*ah) + (2 * ah->ar_pln) + (2 * ah->ar_hln);
1100 break;
1101 }
1102 m->m_pkthdr.len = m->m_len;
1103 sa.sa_family = AF_ARP;
1104 sa.sa_len = 2;
1105 arpstat.as_sndtotal++;
1106 arpstat.as_sndreply++;
1107 (*ifp->if_output)(ifp, m, &sa, (struct rtentry *)0);
1108 return;
1109 }
1110
1111 /*
1112 * Free an arp entry.
1113 */
1114 static void
1115 arptfree(la)
1116 struct llinfo_arp *la;
1117 {
1118 struct rtentry *rt = la->la_rt;
1119 struct sockaddr_dl *sdl;
1120
1121 ARP_LOCK_CHECK();
1122
1123 if (rt == 0)
1124 panic("arptfree");
1125 if (rt->rt_refcnt > 0 && (sdl = SDL(rt->rt_gateway)) &&
1126 sdl->sdl_family == AF_LINK) {
1127 sdl->sdl_alen = 0;
1128 la->la_asked = 0;
1129 rt->rt_flags &= ~RTF_REJECT;
1130 return;
1131 }
1132 rtrequest(RTM_DELETE, rt_key(rt), (struct sockaddr *)0, rt_mask(rt),
1133 0, (struct rtentry **)0);
1134 }
1135
1136 /*
1137 * Lookup or enter a new address in arptab.
1138 */
1139 static struct llinfo_arp *
1140 arplookup(m, addr, create, proxy)
1141 struct mbuf *m;
1142 struct in_addr *addr;
1143 int create, proxy;
1144 {
1145 struct arphdr *ah;
1146 struct ifnet *ifp = m->m_pkthdr.rcvif;
1147 struct rtentry *rt;
1148 static struct sockaddr_inarp sin;
1149 const char *why = 0;
1150
1151 ah = mtod(m, struct arphdr *);
1152 sin.sin_len = sizeof(sin);
1153 sin.sin_family = AF_INET;
1154 sin.sin_addr = *addr;
1155 sin.sin_other = proxy ? SIN_PROXY : 0;
1156 rt = rtalloc1(sintosa(&sin), create);
1157 if (rt == 0)
1158 return (0);
1159 rt->rt_refcnt--;
1160
1161 if (rt->rt_flags & RTF_GATEWAY)
1162 why = "host is not on local network";
1163 else if ((rt->rt_flags & RTF_LLINFO) == 0) {
1164 arpstat.as_allocfail++;
1165 why = "could not allocate llinfo";
1166 } else if (rt->rt_gateway->sa_family != AF_LINK)
1167 why = "gateway route is not ours";
1168 else
1169 return ((struct llinfo_arp *)rt->rt_llinfo);
1170
1171 if (create) {
1172 log(LOG_DEBUG, "arplookup: unable to enter address"
1173 " for %s@%s on %s (%s)\n",
1174 in_fmtaddr(*addr), lla_snprintf(ar_sha(ah), ah->ar_hln),
1175 (ifp) ? ifp->if_xname : 0, why);
1176 if (rt->rt_refcnt <= 0 && (rt->rt_flags & RTF_CLONED) != 0) {
1177 rtrequest(RTM_DELETE, (struct sockaddr *)rt_key(rt),
1178 rt->rt_gateway, rt_mask(rt), rt->rt_flags, 0);
1179 }
1180 }
1181 return (0);
1182 }
1183
1184 int
1185 arpioctl(cmd, data)
1186 u_long cmd;
1187 caddr_t data;
1188 {
1189
1190 return (EOPNOTSUPP);
1191 }
1192
1193 void
1194 arp_ifinit(ifp, ifa)
1195 struct ifnet *ifp;
1196 struct ifaddr *ifa;
1197 {
1198 struct in_addr *ip;
1199
1200 /*
1201 * Warn the user if another station has this IP address,
1202 * but only if the interface IP address is not zero.
1203 */
1204 ip = &IA_SIN(ifa)->sin_addr;
1205 if (!in_nullhost(*ip))
1206 arprequest(ifp, ip, ip, LLADDR(ifp->if_sadl));
1207
1208 ifa->ifa_rtrequest = arp_rtrequest;
1209 ifa->ifa_flags |= RTF_CLONING;
1210 }
1211
1212 /*
1213 * Called from 10 Mb/s Ethernet interrupt handlers
1214 * when ether packet type ETHERTYPE_REVARP
1215 * is received. Common length and type checks are done here,
1216 * then the protocol-specific routine is called.
1217 */
1218 void
1219 revarpinput(m)
1220 struct mbuf *m;
1221 {
1222 struct arphdr *ar;
1223
1224 if (m->m_len < sizeof(struct arphdr))
1225 goto out;
1226 ar = mtod(m, struct arphdr *);
1227 #if 0 /* XXX I don't think we need this... and it will prevent other LL */
1228 if (ntohs(ar->ar_hrd) != ARPHRD_ETHER)
1229 goto out;
1230 #endif
1231 if (m->m_len < sizeof(struct arphdr) + 2 * (ar->ar_hln + ar->ar_pln))
1232 goto out;
1233 switch (ntohs(ar->ar_pro)) {
1234 case ETHERTYPE_IP:
1235 case ETHERTYPE_IPTRAILERS:
1236 in_revarpinput(m);
1237 return;
1238
1239 default:
1240 break;
1241 }
1242 out:
1243 m_freem(m);
1244 }
1245
1246 /*
1247 * RARP for Internet protocols on 10 Mb/s Ethernet.
1248 * Algorithm is that given in RFC 903.
1249 * We are only using for bootstrap purposes to get an ip address for one of
1250 * our interfaces. Thus we support no user-interface.
1251 *
1252 * Since the contents of the RARP reply are specific to the interface that
1253 * sent the request, this code must ensure that they are properly associated.
1254 *
1255 * Note: also supports ARP via RARP packets, per the RFC.
1256 */
1257 void
1258 in_revarpinput(m)
1259 struct mbuf *m;
1260 {
1261 struct ifnet *ifp;
1262 struct arphdr *ah;
1263 int op;
1264
1265 ah = mtod(m, struct arphdr *);
1266 op = ntohs(ah->ar_op);
1267
1268 switch (m->m_pkthdr.rcvif->if_type) {
1269 case IFT_IEEE1394:
1270 /* ARP without target hardware address is not supported */
1271 goto out;
1272 default:
1273 break;
1274 }
1275
1276 switch (op) {
1277 case ARPOP_REQUEST:
1278 case ARPOP_REPLY: /* per RFC */
1279 in_arpinput(m);
1280 return;
1281 case ARPOP_REVREPLY:
1282 break;
1283 case ARPOP_REVREQUEST: /* handled by rarpd(8) */
1284 default:
1285 goto out;
1286 }
1287 if (!revarp_in_progress)
1288 goto out;
1289 ifp = m->m_pkthdr.rcvif;
1290 if (ifp != myip_ifp) /* !same interface */
1291 goto out;
1292 if (myip_initialized)
1293 goto wake;
1294 if (bcmp(ar_tha(ah), LLADDR(ifp->if_sadl), ifp->if_sadl->sdl_alen))
1295 goto out;
1296 bcopy((caddr_t)ar_spa(ah), (caddr_t)&srv_ip, sizeof(srv_ip));
1297 bcopy((caddr_t)ar_tpa(ah), (caddr_t)&myip, sizeof(myip));
1298 myip_initialized = 1;
1299 wake: /* Do wakeup every time in case it was missed. */
1300 wakeup((caddr_t)&myip);
1301
1302 out:
1303 m_freem(m);
1304 }
1305
1306 /*
1307 * Send a RARP request for the ip address of the specified interface.
1308 * The request should be RFC 903-compliant.
1309 */
1310 void
1311 revarprequest(ifp)
1312 struct ifnet *ifp;
1313 {
1314 struct sockaddr sa;
1315 struct mbuf *m;
1316 struct arphdr *ah;
1317
1318 if ((m = m_gethdr(M_DONTWAIT, MT_DATA)) == NULL)
1319 return;
1320 MCLAIM(m, &arpdomain.dom_mowner);
1321 m->m_len = sizeof(*ah) + 2*sizeof(struct in_addr) +
1322 2*ifp->if_addrlen;
1323 m->m_pkthdr.len = m->m_len;
1324 MH_ALIGN(m, m->m_len);
1325 ah = mtod(m, struct arphdr *);
1326 bzero((caddr_t)ah, m->m_len);
1327 ah->ar_pro = htons(ETHERTYPE_IP);
1328 ah->ar_hln = ifp->if_addrlen; /* hardware address length */
1329 ah->ar_pln = sizeof(struct in_addr); /* protocol address length */
1330 ah->ar_op = htons(ARPOP_REVREQUEST);
1331
1332 bcopy(LLADDR(ifp->if_sadl), (caddr_t)ar_sha(ah), ah->ar_hln);
1333 bcopy(LLADDR(ifp->if_sadl), (caddr_t)ar_tha(ah), ah->ar_hln);
1334
1335 sa.sa_family = AF_ARP;
1336 sa.sa_len = 2;
1337 m->m_flags |= M_BCAST;
1338 (*ifp->if_output)(ifp, m, &sa, (struct rtentry *)0);
1339
1340 }
1341
1342 /*
1343 * RARP for the ip address of the specified interface, but also
1344 * save the ip address of the server that sent the answer.
1345 * Timeout if no response is received.
1346 */
1347 int
1348 revarpwhoarewe(ifp, serv_in, clnt_in)
1349 struct ifnet *ifp;
1350 struct in_addr *serv_in;
1351 struct in_addr *clnt_in;
1352 {
1353 int result, count = 20;
1354
1355 myip_initialized = 0;
1356 myip_ifp = ifp;
1357
1358 revarp_in_progress = 1;
1359 while (count--) {
1360 revarprequest(ifp);
1361 result = tsleep((caddr_t)&myip, PSOCK, "revarp", hz/2);
1362 if (result != EWOULDBLOCK)
1363 break;
1364 }
1365 revarp_in_progress = 0;
1366
1367 if (!myip_initialized)
1368 return ENETUNREACH;
1369
1370 bcopy((caddr_t)&srv_ip, serv_in, sizeof(*serv_in));
1371 bcopy((caddr_t)&myip, clnt_in, sizeof(*clnt_in));
1372 return 0;
1373 }
1374
1375
1376
1377 #ifdef DDB
1378
1379 #include <machine/db_machdep.h>
1380 #include <ddb/db_interface.h>
1381 #include <ddb/db_output.h>
1382 static void
1383 db_print_sa(sa)
1384 struct sockaddr *sa;
1385 {
1386 int len;
1387 u_char *p;
1388
1389 if (sa == 0) {
1390 db_printf("[NULL]");
1391 return;
1392 }
1393
1394 p = (u_char*)sa;
1395 len = sa->sa_len;
1396 db_printf("[");
1397 while (len > 0) {
1398 db_printf("%d", *p);
1399 p++; len--;
1400 if (len) db_printf(",");
1401 }
1402 db_printf("]\n");
1403 }
1404 static void
1405 db_print_ifa(ifa)
1406 struct ifaddr *ifa;
1407 {
1408 if (ifa == 0)
1409 return;
1410 db_printf(" ifa_addr=");
1411 db_print_sa(ifa->ifa_addr);
1412 db_printf(" ifa_dsta=");
1413 db_print_sa(ifa->ifa_dstaddr);
1414 db_printf(" ifa_mask=");
1415 db_print_sa(ifa->ifa_netmask);
1416 db_printf(" flags=0x%x,refcnt=%d,metric=%d\n",
1417 ifa->ifa_flags,
1418 ifa->ifa_refcnt,
1419 ifa->ifa_metric);
1420 }
1421 static void
1422 db_print_llinfo(li)
1423 caddr_t li;
1424 {
1425 struct llinfo_arp *la;
1426
1427 if (li == 0)
1428 return;
1429 la = (struct llinfo_arp *)li;
1430 db_printf(" la_rt=%p la_hold=%p, la_asked=0x%lx\n",
1431 la->la_rt, la->la_hold, la->la_asked);
1432 }
1433 /*
1434 * Function to pass to rn_walktree().
1435 * Return non-zero error to abort walk.
1436 */
1437 static int
1438 db_show_radix_node(rn, w)
1439 struct radix_node *rn;
1440 void *w;
1441 {
1442 struct rtentry *rt = (struct rtentry *)rn;
1443
1444 db_printf("rtentry=%p", rt);
1445
1446 db_printf(" flags=0x%x refcnt=%d use=%ld expire=%ld\n",
1447 rt->rt_flags, rt->rt_refcnt,
1448 rt->rt_use, rt->rt_expire);
1449
1450 db_printf(" key="); db_print_sa(rt_key(rt));
1451 db_printf(" mask="); db_print_sa(rt_mask(rt));
1452 db_printf(" gw="); db_print_sa(rt->rt_gateway);
1453
1454 db_printf(" ifp=%p ", rt->rt_ifp);
1455 if (rt->rt_ifp)
1456 db_printf("(%s)", rt->rt_ifp->if_xname);
1457 else
1458 db_printf("(NULL)");
1459
1460 db_printf(" ifa=%p\n", rt->rt_ifa);
1461 db_print_ifa(rt->rt_ifa);
1462
1463 db_printf(" genmask="); db_print_sa(rt->rt_genmask);
1464
1465 db_printf(" gwroute=%p llinfo=%p\n",
1466 rt->rt_gwroute, rt->rt_llinfo);
1467 db_print_llinfo(rt->rt_llinfo);
1468
1469 return (0);
1470 }
1471 /*
1472 * Function to print all the route trees.
1473 * Use this from ddb: "show arptab"
1474 */
1475 void
1476 db_show_arptab(addr, have_addr, count, modif)
1477 db_expr_t addr;
1478 int have_addr;
1479 db_expr_t count;
1480 char * modif;
1481 {
1482 struct radix_node_head *rnh;
1483 rnh = rt_tables[AF_INET];
1484 db_printf("Route tree for AF_INET\n");
1485 if (rnh == NULL) {
1486 db_printf(" (not initialized)\n");
1487 return;
1488 }
1489 rn_walktree(rnh, db_show_radix_node, NULL);
1490 return;
1491 }
1492 #endif
1493 #endif /* INET */
Cache object: d6e9af05f89e79921a34383601f318c1
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