xref: /netbsd-src/sys/netinet/if_arp.c (revision 3b01aba77a7a698587faaae455bbfe740923c1f5)
1 /*	$NetBSD: if_arp.c,v 1.76 2001/07/04 02:29:58 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. All advertising materials mentioning features or use of this software
53  *    must display the following acknowledgement:
54  *	This product includes software developed by the University of
55  *	California, Berkeley and its contributors.
56  * 4. Neither the name of the University nor the names of its contributors
57  *    may be used to endorse or promote products derived from this software
58  *    without specific prior written permission.
59  *
60  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
61  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
62  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
63  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
64  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
65  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
66  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
67  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
68  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
69  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
70  * SUCH DAMAGE.
71  *
72  *	@(#)if_ether.c	8.2 (Berkeley) 9/26/94
73  */
74 
75 /*
76  * Ethernet address resolution protocol.
77  * TODO:
78  *	add "inuse/lock" bit (or ref. count) along with valid bit
79  */
80 
81 #include "opt_ddb.h"
82 #include "opt_inet.h"
83 
84 #ifdef INET
85 
86 #include <sys/param.h>
87 #include <sys/systm.h>
88 #include <sys/callout.h>
89 #include <sys/malloc.h>
90 #include <sys/mbuf.h>
91 #include <sys/socket.h>
92 #include <sys/time.h>
93 #include <sys/kernel.h>
94 #include <sys/errno.h>
95 #include <sys/ioctl.h>
96 #include <sys/syslog.h>
97 #include <sys/proc.h>
98 #include <sys/protosw.h>
99 #include <sys/domain.h>
100 
101 #include <net/ethertypes.h>
102 #include <net/if.h>
103 #include <net/if_dl.h>
104 #include <net/if_token.h>
105 #include <net/if_types.h>
106 #include <net/route.h>
107 
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 #include "token.h"
126 
127 #define SIN(s) ((struct sockaddr_in *)s)
128 #define SDL(s) ((struct sockaddr_dl *)s)
129 #define SRP(s) ((struct sockaddr_inarp *)s)
130 
131 /*
132  * ARP trailer negotiation.  Trailer protocol is not IP specific,
133  * but ARP request/response use IP addresses.
134  */
135 #define ETHERTYPE_IPTRAILERS ETHERTYPE_TRAIL
136 
137 /* timer values */
138 int	arpt_prune = (5*60*1);	/* walk list every 5 minutes */
139 int	arpt_keep = (20*60);	/* once resolved, good for 20 more minutes */
140 int	arpt_down = 20;		/* once declared down, don't send for 20 secs */
141 #define	rt_expire rt_rmx.rmx_expire
142 
143 static	void arprequest __P((struct ifnet *,
144 	    struct in_addr *, struct in_addr *, u_int8_t *));
145 static	void arptfree __P((struct llinfo_arp *));
146 static	void arptimer __P((void *));
147 static	struct llinfo_arp *arplookup __P((struct mbuf *, struct in_addr *,
148 					  int, int));
149 static	void in_arpinput __P((struct mbuf *));
150 
151 #if NLOOP > 0
152 extern	struct ifnet loif[NLOOP];
153 #endif
154 LIST_HEAD(, llinfo_arp) llinfo_arp;
155 struct	ifqueue arpintrq = {0, 0, 0, 50};
156 int	arp_inuse, arp_allocated, arp_intimer;
157 int	arp_maxtries = 5;
158 int	useloopback = 1;	/* use loopback interface for local traffic */
159 int	arpinit_done = 0;
160 
161 struct	arpstat arpstat;
162 struct	callout arptimer_ch;
163 
164 
165 /* revarp state */
166 static struct	in_addr myip, srv_ip;
167 static int	myip_initialized = 0;
168 static int	revarp_in_progress = 0;
169 static struct	ifnet *myip_ifp = NULL;
170 
171 #ifdef DDB
172 static void db_print_sa __P((struct sockaddr *));
173 static void db_print_ifa __P((struct ifaddr *));
174 static void db_print_llinfo __P((caddr_t));
175 static int db_show_radix_node __P((struct radix_node *, void *));
176 #endif
177 
178 /*
179  * this should be elsewhere.
180  */
181 
182 static char *
183 lla_snprintf __P((u_int8_t *, int));
184 
185 static char *
186 lla_snprintf(adrp, len)
187 	u_int8_t *adrp;
188 	int len;
189 {
190 #define NUMBUFS 3
191 	static char buf[NUMBUFS][16*3];
192 	static int bnum = 0;
193 	static const char hexdigits[] = {
194 	    '0','1','2','3','4','5','6','7',
195 	    '8','9','a','b','c','d','e','f'
196 	};
197 
198 	int i;
199 	char *p;
200 
201 	p = buf[bnum];
202 
203 	*p++ = hexdigits[(*adrp)>>4];
204 	*p++ = hexdigits[(*adrp++)&0xf];
205 
206 	for (i=1; i<len && i<16; i++) {
207 		*p++ = ':';
208 		*p++ = hexdigits[(*adrp)>>4];
209 		*p++ = hexdigits[(*adrp++)&0xf];
210 	}
211 
212 	*p = 0;
213 	p = buf[bnum];
214 	bnum = (bnum + 1) % NUMBUFS;
215 	return p;
216 }
217 
218 struct protosw arpsw[] = {
219 	{ 0, 0, 0, 0,
220 	  0, 0, 0, 0,
221 	  0,
222 	  0, 0, 0, arp_drain,
223 	}
224 };
225 
226 
227 struct domain arpdomain =
228 { 	PF_ARP,  "arp", 0, 0, 0,
229 	arpsw, &arpsw[sizeof(arpsw)/sizeof(arpsw[0])]
230 };
231 
232 /*
233  * ARP table locking.
234  *
235  * to prevent lossage vs. the arp_drain routine (which may be called at
236  * any time, including in a device driver context), we do two things:
237  *
238  * 1) manipulation of la->la_hold is done at splnet() (for all of
239  * about two instructions).
240  *
241  * 2) manipulation of the arp table's linked list is done under the
242  * protection of the ARP_LOCK; if arp_drain() or arptimer is called
243  * while the arp table is locked, we punt and try again later.
244  */
245 
246 int	arp_locked;
247 
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 (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 (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 	if (rt->rt_flags & RTF_GATEWAY)
399 		return;
400 
401 	ARP_LOCK(1);		/* we may already be locked here. */
402 
403 	switch (req) {
404 
405 	case RTM_ADD:
406 		/*
407 		 * XXX: If this is a manually added route to interface
408 		 * such as older version of routed or gated might provide,
409 		 * restore cloning bit.
410 		 */
411 		if ((rt->rt_flags & RTF_HOST) == 0 &&
412 		    SIN(rt_mask(rt))->sin_addr.s_addr != 0xffffffff)
413 			rt->rt_flags |= RTF_CLONING;
414 		if (rt->rt_flags & RTF_CLONING) {
415 			/*
416 			 * Case 1: This route should come from a route to iface.
417 			 */
418 			rt_setgate(rt, rt_key(rt),
419 					(struct sockaddr *)&null_sdl);
420 			gate = rt->rt_gateway;
421 			SDL(gate)->sdl_type = rt->rt_ifp->if_type;
422 			SDL(gate)->sdl_index = rt->rt_ifp->if_index;
423 			/*
424 			 * Give this route an expiration time, even though
425 			 * it's a "permanent" route, so that routes cloned
426 			 * from it do not need their expiration time set.
427 			 */
428 			rt->rt_expire = time.tv_sec;
429 #if NFDDI > 0
430 			if (rt->rt_ifp->if_type == IFT_FDDI
431 			    && (rt->rt_rmx.rmx_mtu > FDDIIPMTU
432 				|| (rt->rt_rmx.rmx_mtu == 0
433 				    && rt->rt_ifp->if_mtu > FDDIIPMTU))) {
434 				rt->rt_rmx.rmx_mtu = FDDIIPMTU;
435 			}
436 #endif
437 #if NARC > 0
438 			if (rt->rt_ifp->if_type == IFT_ARCNET) {
439 				int arcipifmtu;
440 
441 				if (rt->rt_ifp->if_flags & IFF_LINK0)
442 					arcipifmtu = arc_ipmtu;
443 				else
444 					arcipifmtu = ARCMTU;
445 
446 			    	if (rt->rt_rmx.rmx_mtu > arcipifmtu ||
447 				    (rt->rt_rmx.rmx_mtu == 0 &&
448 				     rt->rt_ifp->if_mtu > arcipifmtu))
449 
450 					rt->rt_rmx.rmx_mtu = arcipifmtu;
451 			}
452 #endif
453 			break;
454 		}
455 		/* Announce a new entry if requested. */
456 		if (rt->rt_flags & RTF_ANNOUNCE)
457 			arprequest(rt->rt_ifp,
458 			    &SIN(rt_key(rt))->sin_addr,
459 			    &SIN(rt_key(rt))->sin_addr,
460 			    (u_char *)LLADDR(SDL(gate)));
461 		/*FALLTHROUGH*/
462 	case RTM_RESOLVE:
463 		if (gate->sa_family != AF_LINK ||
464 		    gate->sa_len < sizeof(null_sdl)) {
465 			log(LOG_DEBUG, "arp_rtrequest: bad gateway value\n");
466 			break;
467 		}
468 		SDL(gate)->sdl_type = rt->rt_ifp->if_type;
469 		SDL(gate)->sdl_index = rt->rt_ifp->if_index;
470 		if (la != 0)
471 			break; /* This happens on a route change */
472 		/*
473 		 * Case 2:  This route may come from cloning, or a manual route
474 		 * add with a LL address.
475 		 */
476 		switch (SDL(gate)->sdl_type) {
477 #if NTOKEN > 0
478 		case IFT_ISO88025:
479 			allocsize = sizeof(*la) + sizeof(struct token_rif);
480 			break;
481 #endif /* NTOKEN > 0 */
482 		default:
483 			allocsize = sizeof(*la);
484 		}
485 		R_Malloc(la, struct llinfo_arp *, allocsize);
486 		rt->rt_llinfo = (caddr_t)la;
487 		if (la == 0) {
488 			log(LOG_DEBUG, "arp_rtrequest: malloc failed\n");
489 			break;
490 		}
491 		arp_inuse++, arp_allocated++;
492 		Bzero(la, allocsize);
493 		la->la_rt = rt;
494 		rt->rt_flags |= RTF_LLINFO;
495 		LIST_INSERT_HEAD(&llinfo_arp, la, la_list);
496 
497 		INADDR_TO_IA(SIN(rt_key(rt))->sin_addr, ia);
498 		while (ia && ia->ia_ifp != rt->rt_ifp)
499 			NEXT_IA_WITH_SAME_ADDR(ia);
500 		if (ia) {
501 			/*
502 			 * This test used to be
503 			 *	if (loif.if_flags & IFF_UP)
504 			 * It allowed local traffic to be forced through
505 			 * the hardware by configuring the loopback down.
506 			 * However, it causes problems during network
507 			 * configuration for boards that can't receive
508 			 * packets they send.  It is now necessary to clear
509 			 * "useloopback" and remove the route to force
510 			 * traffic out to the hardware.
511 			 *
512 			 * In 4.4BSD, the above "if" statement checked
513 			 * rt->rt_ifa against rt_key(rt).  It was changed
514 			 * to the current form so that we can provide a
515 			 * better support for multiple IPv4 addresses on a
516 			 * interface.
517 			 */
518 			rt->rt_expire = 0;
519 			Bcopy(LLADDR(rt->rt_ifp->if_sadl),
520 			    LLADDR(SDL(gate)),
521 			    SDL(gate)->sdl_alen =
522 			    rt->rt_ifp->if_data.ifi_addrlen);
523 #if NLOOP > 0
524 			if (useloopback)
525 				rt->rt_ifp = &loif[0];
526 #endif
527 			/*
528 			 * make sure to set rt->rt_ifa to the interface
529 			 * address we are using, otherwise we will have trouble
530 			 * with source address selection.
531 			 */
532 			ifa = &ia->ia_ifa;
533 			if (ifa != rt->rt_ifa) {
534 				IFAFREE(rt->rt_ifa);
535 				IFAREF(ifa);
536 				rt->rt_ifa = ifa;
537 			}
538 		}
539 		break;
540 
541 	case RTM_DELETE:
542 		if (la == 0)
543 			break;
544 		arp_inuse--;
545 		LIST_REMOVE(la, la_list);
546 		rt->rt_llinfo = 0;
547 		rt->rt_flags &= ~RTF_LLINFO;
548 
549 		s = splnet();
550 		mold = la->la_hold;
551 		la->la_hold = 0;
552 		splx(s);
553 
554 		if (mold)
555 			m_freem(mold);
556 
557 		Free((caddr_t)la);
558 	}
559 	ARP_UNLOCK();
560 }
561 
562 /*
563  * Broadcast an ARP request. Caller specifies:
564  *	- arp header source ip address
565  *	- arp header target ip address
566  *	- arp header source ethernet address
567  */
568 static void
569 arprequest(ifp, sip, tip, enaddr)
570 	struct ifnet *ifp;
571 	struct in_addr *sip, *tip;
572 	u_int8_t *enaddr;
573 {
574 	struct mbuf *m;
575 	struct arphdr *ah;
576 	struct sockaddr sa;
577 
578 	if ((m = m_gethdr(M_DONTWAIT, MT_DATA)) == NULL)
579 		return;
580 	m->m_len = sizeof(*ah) + 2*sizeof(struct in_addr) +
581 	    2*ifp->if_data.ifi_addrlen;
582 	m->m_pkthdr.len = m->m_len;
583 	MH_ALIGN(m, m->m_len);
584 	ah = mtod(m, struct arphdr *);
585 	bzero((caddr_t)ah, m->m_len);
586 	ah->ar_pro = htons(ETHERTYPE_IP);
587 	ah->ar_hln = ifp->if_data.ifi_addrlen;	/* hardware address length */
588 	ah->ar_pln = sizeof(struct in_addr);	/* protocol address length */
589 	ah->ar_op = htons(ARPOP_REQUEST);
590 	bcopy((caddr_t)enaddr, (caddr_t)ar_sha(ah), ah->ar_hln);
591 	bcopy((caddr_t)sip, (caddr_t)ar_spa(ah), ah->ar_pln);
592 	bcopy((caddr_t)tip, (caddr_t)ar_tpa(ah), ah->ar_pln);
593 	sa.sa_family = AF_ARP;
594 	sa.sa_len = 2;
595 	m->m_flags |= M_BCAST;
596 	arpstat.as_sndtotal++;
597 	arpstat.as_sndrequest++;
598 	(*ifp->if_output)(ifp, m, &sa, (struct rtentry *)0);
599 }
600 
601 /*
602  * Resolve an IP address into an ethernet address.  If success,
603  * desten is filled in.  If there is no entry in arptab,
604  * set one up and broadcast a request for the IP address.
605  * Hold onto this mbuf and resend it once the address
606  * is finally resolved.  A return value of 1 indicates
607  * that desten has been filled in and the packet should be sent
608  * normally; a 0 return indicates that the packet has been
609  * taken over here, either now or for later transmission.
610  */
611 int
612 arpresolve(ifp, rt, m, dst, desten)
613 	struct ifnet *ifp;
614 	struct rtentry *rt;
615 	struct mbuf *m;
616 	struct sockaddr *dst;
617 	u_char *desten;
618 {
619 	struct llinfo_arp *la;
620 	struct sockaddr_dl *sdl;
621 	struct mbuf *mold;
622 	int s;
623 
624 	if (rt)
625 		la = (struct llinfo_arp *)rt->rt_llinfo;
626 	else {
627 		if ((la = arplookup(m, &SIN(dst)->sin_addr, 1, 0)) != NULL)
628 			rt = la->la_rt;
629 	}
630 	if (la == 0 || rt == 0) {
631 		arpstat.as_allocfail++;
632 		log(LOG_DEBUG,
633 		    "arpresolve: can't allocate llinfo on %s for %s\n",
634 		    ifp->if_xname, in_fmtaddr(SIN(dst)->sin_addr));
635 		m_freem(m);
636 		return (0);
637 	}
638 	sdl = SDL(rt->rt_gateway);
639 	/*
640 	 * Check the address family and length is valid, the address
641 	 * is resolved; otherwise, try to resolve.
642 	 */
643 	if ((rt->rt_expire == 0 || rt->rt_expire > time.tv_sec) &&
644 	    sdl->sdl_family == AF_LINK && sdl->sdl_alen != 0) {
645 		bcopy(LLADDR(sdl), desten,
646 		    min(sdl->sdl_alen, ifp->if_data.ifi_addrlen));
647 		return 1;
648 	}
649 	/*
650 	 * There is an arptab entry, but no ethernet address
651 	 * response yet.  Replace the held mbuf with this
652 	 * latest one.
653 	 */
654 
655 	arpstat.as_dfrtotal++;
656 	s = splnet();
657 	mold = la->la_hold;
658 	la->la_hold = m;
659 	splx(s);
660 
661 	if (mold) {
662 		arpstat.as_dfrdropped++;
663 		m_freem(mold);
664 	}
665 
666 	/*
667 	 * Re-send the ARP request when appropriate.
668 	 */
669 #ifdef	DIAGNOSTIC
670 	if (rt->rt_expire == 0) {
671 		/* This should never happen. (Should it? -gwr) */
672 		printf("arpresolve: unresolved and rt_expire == 0\n");
673 		/* Set expiration time to now (expired). */
674 		rt->rt_expire = time.tv_sec;
675 	}
676 #endif
677 	if (rt->rt_expire) {
678 		rt->rt_flags &= ~RTF_REJECT;
679 		if (la->la_asked == 0 || rt->rt_expire != time.tv_sec) {
680 			rt->rt_expire = time.tv_sec;
681 			if (la->la_asked++ < arp_maxtries)
682 				arprequest(ifp,
683 				    &SIN(rt->rt_ifa->ifa_addr)->sin_addr,
684 				    &SIN(dst)->sin_addr,
685 				    LLADDR(ifp->if_sadl));
686 			else {
687 				rt->rt_flags |= RTF_REJECT;
688 				rt->rt_expire += arpt_down;
689 				la->la_asked = 0;
690 			}
691 		}
692 	}
693 	return (0);
694 }
695 
696 /*
697  * Common length and type checks are done here,
698  * then the protocol-specific routine is called.
699  */
700 void
701 arpintr()
702 {
703 	struct mbuf *m;
704 	struct arphdr *ar;
705 	int s;
706 
707 	while (arpintrq.ifq_head) {
708 		s = splnet();
709 		IF_DEQUEUE(&arpintrq, m);
710 		splx(s);
711 		if (m == 0 || (m->m_flags & M_PKTHDR) == 0)
712 			panic("arpintr");
713 
714 		arpstat.as_rcvtotal++;
715 
716 		if (m->m_len >= sizeof(struct arphdr) &&
717 		    (ar = mtod(m, struct arphdr *)) &&
718 		    /* XXX ntohs(ar->ar_hrd) == ARPHRD_ETHER && */
719 		    m->m_len >=
720 		      sizeof(struct arphdr) + 2 * (ar->ar_hln + ar->ar_pln))
721 			switch (ntohs(ar->ar_pro)) {
722 
723 			case ETHERTYPE_IP:
724 			case ETHERTYPE_IPTRAILERS:
725 				in_arpinput(m);
726 				continue;
727 			default:
728 				arpstat.as_rcvbadproto++;
729 			}
730 		else
731 			arpstat.as_rcvbadlen++;
732 		m_freem(m);
733 	}
734 }
735 
736 /*
737  * ARP for Internet protocols on 10 Mb/s Ethernet.
738  * Algorithm is that given in RFC 826.
739  * In addition, a sanity check is performed on the sender
740  * protocol address, to catch impersonators.
741  * We no longer handle negotiations for use of trailer protocol:
742  * Formerly, ARP replied for protocol type ETHERTYPE_TRAIL sent
743  * along with IP replies if we wanted trailers sent to us,
744  * and also sent them in response to IP replies.
745  * This allowed either end to announce the desire to receive
746  * trailer packets.
747  * We no longer reply to requests for ETHERTYPE_TRAIL protocol either,
748  * but formerly didn't normally send requests.
749  */
750 static void
751 in_arpinput(m)
752 	struct mbuf *m;
753 {
754 	struct arphdr *ah;
755 	struct ifnet *ifp = m->m_pkthdr.rcvif;
756 	struct llinfo_arp *la = 0;
757 	struct rtentry  *rt;
758 	struct in_ifaddr *ia;
759 	struct sockaddr_dl *sdl;
760 	struct sockaddr sa;
761 	struct in_addr isaddr, itaddr, myaddr;
762 	int op;
763 	struct mbuf *mold;
764 	int s;
765 
766 	ah = mtod(m, struct arphdr *);
767 	op = ntohs(ah->ar_op);
768 	bcopy((caddr_t)ar_spa(ah), (caddr_t)&isaddr, sizeof (isaddr));
769 	bcopy((caddr_t)ar_tpa(ah), (caddr_t)&itaddr, sizeof (itaddr));
770 
771 	if (m->m_flags & (M_BCAST|M_MCAST))
772 		arpstat.as_rcvmcast++;
773 
774 	/*
775 	 * If the target IP address is zero, ignore the packet.
776 	 * This prevents the code below from tring to answer
777 	 * when we are using IP address zero (booting).
778 	 */
779 	if (in_nullhost(itaddr)) {
780 		arpstat.as_rcvzerotpa++;
781 		goto out;
782 	}
783 
784 	/*
785 	 * If the source IP address is zero, this is most likely a
786 	 * confused host trying to use IP address zero. (Windoze?)
787 	 * XXX: Should we bother trying to reply to these?
788 	 */
789 	if (in_nullhost(isaddr)) {
790 		arpstat.as_rcvzerospa++;
791 		goto out;
792 	}
793 
794 	/*
795 	 * Search for a matching interface address
796 	 * or any address on the interface to use
797 	 * as a dummy address in the rest of this function
798 	 */
799 	INADDR_TO_IA(itaddr, ia);
800 	while ((ia != NULL) && ia->ia_ifp != m->m_pkthdr.rcvif)
801 		NEXT_IA_WITH_SAME_ADDR(ia);
802 
803 	if (ia == NULL) {
804 		INADDR_TO_IA(isaddr, ia);
805 		while ((ia != NULL) && ia->ia_ifp != m->m_pkthdr.rcvif)
806 			NEXT_IA_WITH_SAME_ADDR(ia);
807 
808 		if (ia == NULL) {
809 			IFP_TO_IA(ifp, ia);
810 			if (ia == NULL) {
811 				arpstat.as_rcvnoint++;
812 				goto out;
813 			}
814 		}
815 	}
816 
817 	myaddr = ia->ia_addr.sin_addr;
818 
819 	if (!bcmp((caddr_t)ar_sha(ah), LLADDR(ifp->if_sadl),
820 	    ifp->if_data.ifi_addrlen)) {
821 		arpstat.as_rcvlocalsha++;
822 		goto out;	/* it's from me, ignore it. */
823 	}
824 
825 	if (!bcmp((caddr_t)ar_sha(ah), (caddr_t)ifp->if_broadcastaddr,
826 	    ifp->if_data.ifi_addrlen)) {
827 		arpstat.as_rcvbcastsha++;
828 		log(LOG_ERR,
829 		    "%s: arp: link address is broadcast for IP address %s!\n",
830 		    ifp->if_xname, in_fmtaddr(isaddr));
831 		goto out;
832 	}
833 
834 	if (in_hosteq(isaddr, myaddr)) {
835 		arpstat.as_rcvlocalspa++;
836 		log(LOG_ERR,
837 		   "duplicate IP address %s sent from link address %s\n",
838 		   in_fmtaddr(isaddr), lla_snprintf(ar_sha(ah), ah->ar_hln));
839 		itaddr = myaddr;
840 		goto reply;
841 	}
842 	la = arplookup(m, &isaddr, in_hosteq(itaddr, myaddr), 0);
843 	if (la && (rt = la->la_rt) && (sdl = SDL(rt->rt_gateway))) {
844 		if (sdl->sdl_alen &&
845 		    bcmp((caddr_t)ar_sha(ah), LLADDR(sdl), sdl->sdl_alen)) {
846 			if (rt->rt_flags & RTF_STATIC) {
847 				arpstat.as_rcvoverperm++;
848 				log(LOG_INFO,
849 				    "%s tried to overwrite permanent arp info"
850 				    " for %s\n",
851 				    lla_snprintf(ar_sha(ah), ah->ar_hln),
852 				    in_fmtaddr(isaddr));
853 				goto out;
854 			} else if (rt->rt_ifp != ifp) {
855 				arpstat.as_rcvoverint++;
856 				log(LOG_INFO,
857 				    "%s on %s tried to overwrite "
858 				    "arp info for %s on %s\n",
859 				    lla_snprintf(ar_sha(ah), ah->ar_hln),
860 				    ifp->if_xname, in_fmtaddr(isaddr),
861 				    rt->rt_ifp->if_xname);
862 				    goto out;
863 			} else {
864 				arpstat.as_rcvover++;
865 				log(LOG_INFO,
866 				    "arp info overwritten for %s by %s\n",
867 				    in_fmtaddr(isaddr),
868 				    lla_snprintf(ar_sha(ah), ah->ar_hln));
869 			}
870 		}
871 		/*
872 		 * sanity check for the address length.
873 		 * XXX this does not work for protocols with variable address
874 		 * length. -is
875 		 */
876 		if (sdl->sdl_alen &&
877 		    sdl->sdl_alen != ah->ar_hln) {
878 			arpstat.as_rcvlenchg++;
879 			log(LOG_WARNING,
880 			    "arp from %s: new addr len %d, was %d",
881 			    in_fmtaddr(isaddr), ah->ar_hln, sdl->sdl_alen);
882 		}
883 		if (ifp->if_data.ifi_addrlen != ah->ar_hln) {
884 			arpstat.as_rcvbadlen++;
885 			log(LOG_WARNING,
886 			    "arp from %s: addr len: new %d, i/f %d (ignored)",
887 			    in_fmtaddr(isaddr), ah->ar_hln,
888 			    ifp->if_data.ifi_addrlen);
889 			goto reply;
890 		}
891 #if NTOKEN > 0
892 		/*
893 		 * XXX uses m_data and assumes the complete answer including
894 		 * XXX token-ring headers is in the same buf
895 		 */
896 		if (ifp->if_type == IFT_ISO88025) {
897 			struct token_header *trh;
898 
899 			trh = (struct token_header *)M_TRHSTART(m);
900 			if (trh->token_shost[0] & TOKEN_RI_PRESENT) {
901 				struct token_rif	*rif;
902 				size_t	riflen;
903 
904 				rif = TOKEN_RIF(trh);
905 				riflen = (ntohs(rif->tr_rcf) &
906 				    TOKEN_RCF_LEN_MASK) >> 8;
907 
908 				if (riflen > 2 &&
909 				    riflen < sizeof(struct token_rif) &&
910 				    (riflen & 1) == 0) {
911 					rif->tr_rcf ^= htons(TOKEN_RCF_DIRECTION);
912 					rif->tr_rcf &= htons(~TOKEN_RCF_BROADCAST_MASK);
913 					bcopy(rif, TOKEN_RIF(la), riflen);
914 				}
915 			}
916 		}
917 #endif /* NTOKEN > 0 */
918 		bcopy((caddr_t)ar_sha(ah), LLADDR(sdl),
919 		    sdl->sdl_alen = ah->ar_hln);
920 		if (rt->rt_expire)
921 			rt->rt_expire = time.tv_sec + arpt_keep;
922 		rt->rt_flags &= ~RTF_REJECT;
923 		la->la_asked = 0;
924 
925 		s = splnet();
926 		mold = la->la_hold;
927 		la->la_hold = 0;
928 		splx(s);
929 
930 		if (mold) {
931 			arpstat.as_dfrsent++;
932 			(*ifp->if_output)(ifp, mold, rt_key(rt), rt);
933 		}
934 	}
935 reply:
936 	if (op != ARPOP_REQUEST) {
937 		if (op == ARPOP_REPLY)
938 			arpstat.as_rcvreply++;
939 	out:
940 		m_freem(m);
941 		return;
942 	}
943 	arpstat.as_rcvrequest++;
944 	if (in_hosteq(itaddr, myaddr)) {
945 		/* I am the target */
946 		bcopy((caddr_t)ar_sha(ah), (caddr_t)ar_tha(ah), ah->ar_hln);
947 		bcopy(LLADDR(ifp->if_sadl), (caddr_t)ar_sha(ah), ah->ar_hln);
948 	} else {
949 		la = arplookup(m, &itaddr, 0, SIN_PROXY);
950 		if (la == 0)
951 			goto out;
952 		rt = la->la_rt;
953 		bcopy((caddr_t)ar_sha(ah), (caddr_t)ar_tha(ah), ah->ar_hln);
954 		sdl = SDL(rt->rt_gateway);
955 		bcopy(LLADDR(sdl), (caddr_t)ar_sha(ah), ah->ar_hln);
956 	}
957 
958 	bcopy((caddr_t)ar_spa(ah), (caddr_t)ar_tpa(ah), ah->ar_pln);
959 	bcopy((caddr_t)&itaddr, (caddr_t)ar_spa(ah), ah->ar_pln);
960 	ah->ar_op = htons(ARPOP_REPLY);
961 	ah->ar_pro = htons(ETHERTYPE_IP); /* let's be sure! */
962 	m->m_flags &= ~(M_BCAST|M_MCAST); /* never reply by broadcast */
963 	m->m_len = sizeof(*ah) + (2 * ah->ar_pln) + (2 * ah->ar_hln);
964 	m->m_pkthdr.len = m->m_len;
965 	sa.sa_family = AF_ARP;
966 	sa.sa_len = 2;
967 	arpstat.as_sndtotal++;
968 	arpstat.as_sndreply++;
969 	(*ifp->if_output)(ifp, m, &sa, (struct rtentry *)0);
970 	return;
971 }
972 
973 /*
974  * Free an arp entry.
975  */
976 static void
977 arptfree(la)
978 	struct llinfo_arp *la;
979 {
980 	struct rtentry *rt = la->la_rt;
981 	struct sockaddr_dl *sdl;
982 
983 	ARP_LOCK_CHECK();
984 
985 	if (rt == 0)
986 		panic("arptfree");
987 	if (rt->rt_refcnt > 0 && (sdl = SDL(rt->rt_gateway)) &&
988 	    sdl->sdl_family == AF_LINK) {
989 		sdl->sdl_alen = 0;
990 		la->la_asked = 0;
991 		rt->rt_flags &= ~RTF_REJECT;
992 		return;
993 	}
994 	rtrequest(RTM_DELETE, rt_key(rt), (struct sockaddr *)0, rt_mask(rt),
995 	    0, (struct rtentry **)0);
996 }
997 
998 /*
999  * Lookup or enter a new address in arptab.
1000  */
1001 static struct llinfo_arp *
1002 arplookup(m, addr, create, proxy)
1003 	struct mbuf *m;
1004 	struct in_addr *addr;
1005 	int create, proxy;
1006 {
1007 	struct arphdr *ah;
1008 	struct ifnet *ifp = m->m_pkthdr.rcvif;
1009 	struct rtentry *rt;
1010 	static struct sockaddr_inarp sin;
1011 	const char *why = 0;
1012 
1013 	ah = mtod(m, struct arphdr *);
1014 	sin.sin_len = sizeof(sin);
1015 	sin.sin_family = AF_INET;
1016 	sin.sin_addr = *addr;
1017 	sin.sin_other = proxy ? SIN_PROXY : 0;
1018 	rt = rtalloc1(sintosa(&sin), create);
1019 	if (rt == 0)
1020 		return (0);
1021 	rt->rt_refcnt--;
1022 
1023 	if (rt->rt_flags & RTF_GATEWAY)
1024 		why = "host is not on local network";
1025 	else if ((rt->rt_flags & RTF_LLINFO) == 0) {
1026 		arpstat.as_allocfail++;
1027 		why = "could not allocate llinfo";
1028 	} else if (rt->rt_gateway->sa_family != AF_LINK)
1029 		why = "gateway route is not ours";
1030 	else
1031 		return ((struct llinfo_arp *)rt->rt_llinfo);
1032 
1033 	if (create)
1034 		log(LOG_DEBUG, "arplookup: unable to enter address"
1035 		    " for %s@%s on %s (%s)\n",
1036 		    in_fmtaddr(*addr), lla_snprintf(ar_sha(ah), ah->ar_hln),
1037 		    ifp->if_xname, why);
1038 	return (0);
1039 }
1040 
1041 int
1042 arpioctl(cmd, data)
1043 	u_long cmd;
1044 	caddr_t data;
1045 {
1046 
1047 	return (EOPNOTSUPP);
1048 }
1049 
1050 void
1051 arp_ifinit(ifp, ifa)
1052 	struct ifnet *ifp;
1053 	struct ifaddr *ifa;
1054 {
1055 	struct in_addr *ip;
1056 
1057 	/*
1058 	 * Warn the user if another station has this IP address,
1059 	 * but only if the interface IP address is not zero.
1060 	 */
1061 	ip = &IA_SIN(ifa)->sin_addr;
1062 	if (!in_nullhost(*ip))
1063 		arprequest(ifp, ip, ip, LLADDR(ifp->if_sadl));
1064 
1065 	ifa->ifa_rtrequest = arp_rtrequest;
1066 	ifa->ifa_flags |= RTF_CLONING;
1067 }
1068 
1069 /*
1070  * Called from 10 Mb/s Ethernet interrupt handlers
1071  * when ether packet type ETHERTYPE_REVARP
1072  * is received.  Common length and type checks are done here,
1073  * then the protocol-specific routine is called.
1074  */
1075 void
1076 revarpinput(m)
1077 	struct mbuf *m;
1078 {
1079 	struct arphdr *ar;
1080 
1081 	if (m->m_len < sizeof(struct arphdr))
1082 		goto out;
1083 	ar = mtod(m, struct arphdr *);
1084 #if 0 /* XXX I don't think we need this... and it will prevent other LL */
1085 	if (ntohs(ar->ar_hrd) != ARPHRD_ETHER)
1086 		goto out;
1087 #endif
1088 	if (m->m_len < sizeof(struct arphdr) + 2 * (ar->ar_hln + ar->ar_pln))
1089 		goto out;
1090 	switch (ntohs(ar->ar_pro)) {
1091 
1092 	case ETHERTYPE_IP:
1093 	case ETHERTYPE_IPTRAILERS:
1094 		in_revarpinput(m);
1095 		return;
1096 
1097 	default:
1098 		break;
1099 	}
1100 out:
1101 	m_freem(m);
1102 }
1103 
1104 /*
1105  * RARP for Internet protocols on 10 Mb/s Ethernet.
1106  * Algorithm is that given in RFC 903.
1107  * We are only using for bootstrap purposes to get an ip address for one of
1108  * our interfaces.  Thus we support no user-interface.
1109  *
1110  * Since the contents of the RARP reply are specific to the interface that
1111  * sent the request, this code must ensure that they are properly associated.
1112  *
1113  * Note: also supports ARP via RARP packets, per the RFC.
1114  */
1115 void
1116 in_revarpinput(m)
1117 	struct mbuf *m;
1118 {
1119 	struct ifnet *ifp;
1120 	struct arphdr *ah;
1121 	int op;
1122 
1123 	ah = mtod(m, struct arphdr *);
1124 	op = ntohs(ah->ar_op);
1125 	switch (op) {
1126 	case ARPOP_REQUEST:
1127 	case ARPOP_REPLY:	/* per RFC */
1128 		in_arpinput(m);
1129 		return;
1130 	case ARPOP_REVREPLY:
1131 		break;
1132 	case ARPOP_REVREQUEST:	/* handled by rarpd(8) */
1133 	default:
1134 		goto out;
1135 	}
1136 	if (!revarp_in_progress)
1137 		goto out;
1138 	ifp = m->m_pkthdr.rcvif;
1139 	if (ifp != myip_ifp) /* !same interface */
1140 		goto out;
1141 	if (myip_initialized)
1142 		goto wake;
1143 	if (bcmp(ar_tha(ah), LLADDR(ifp->if_sadl), ifp->if_sadl->sdl_alen))
1144 		goto out;
1145 	bcopy((caddr_t)ar_spa(ah), (caddr_t)&srv_ip, sizeof(srv_ip));
1146 	bcopy((caddr_t)ar_tpa(ah), (caddr_t)&myip, sizeof(myip));
1147 	myip_initialized = 1;
1148 wake:	/* Do wakeup every time in case it was missed. */
1149 	wakeup((caddr_t)&myip);
1150 
1151 out:
1152 	m_freem(m);
1153 }
1154 
1155 /*
1156  * Send a RARP request for the ip address of the specified interface.
1157  * The request should be RFC 903-compliant.
1158  */
1159 void
1160 revarprequest(ifp)
1161 	struct ifnet *ifp;
1162 {
1163 	struct sockaddr sa;
1164 	struct mbuf *m;
1165 	struct arphdr *ah;
1166 
1167 	if ((m = m_gethdr(M_DONTWAIT, MT_DATA)) == NULL)
1168 		return;
1169 	m->m_len = sizeof(*ah) + 2*sizeof(struct in_addr) +
1170 	    2*ifp->if_data.ifi_addrlen;
1171 	m->m_pkthdr.len = m->m_len;
1172 	MH_ALIGN(m, m->m_len);
1173 	ah = mtod(m, struct arphdr *);
1174 	bzero((caddr_t)ah, m->m_len);
1175 	ah->ar_pro = htons(ETHERTYPE_IP);
1176 	ah->ar_hln = ifp->if_data.ifi_addrlen;	/* hardware address length */
1177 	ah->ar_pln = sizeof(struct in_addr);	/* protocol address length */
1178 	ah->ar_op = htons(ARPOP_REVREQUEST);
1179 
1180 	bcopy(LLADDR(ifp->if_sadl), (caddr_t)ar_sha(ah), ah->ar_hln);
1181 	bcopy(LLADDR(ifp->if_sadl), (caddr_t)ar_tha(ah), ah->ar_hln);
1182 
1183 	sa.sa_family = AF_ARP;
1184 	sa.sa_len = 2;
1185 	m->m_flags |= M_BCAST;
1186 	(*ifp->if_output)(ifp, m, &sa, (struct rtentry *)0);
1187 
1188 }
1189 
1190 /*
1191  * RARP for the ip address of the specified interface, but also
1192  * save the ip address of the server that sent the answer.
1193  * Timeout if no response is received.
1194  */
1195 int
1196 revarpwhoarewe(ifp, serv_in, clnt_in)
1197 	struct ifnet *ifp;
1198 	struct in_addr *serv_in;
1199 	struct in_addr *clnt_in;
1200 {
1201 	int result, count = 20;
1202 
1203 	myip_initialized = 0;
1204 	myip_ifp = ifp;
1205 
1206 	revarp_in_progress = 1;
1207 	while (count--) {
1208 		revarprequest(ifp);
1209 		result = tsleep((caddr_t)&myip, PSOCK, "revarp", hz/2);
1210 		if (result != EWOULDBLOCK)
1211 			break;
1212 	}
1213 	revarp_in_progress = 0;
1214 
1215 	if (!myip_initialized)
1216 		return ENETUNREACH;
1217 
1218 	bcopy((caddr_t)&srv_ip, serv_in, sizeof(*serv_in));
1219 	bcopy((caddr_t)&myip, clnt_in, sizeof(*clnt_in));
1220 	return 0;
1221 }
1222 
1223 
1224 
1225 #ifdef DDB
1226 
1227 #include <machine/db_machdep.h>
1228 #include <ddb/db_interface.h>
1229 #include <ddb/db_output.h>
1230 static void
1231 db_print_sa(sa)
1232 	struct sockaddr *sa;
1233 {
1234 	int len;
1235 	u_char *p;
1236 
1237 	if (sa == 0) {
1238 		db_printf("[NULL]");
1239 		return;
1240 	}
1241 
1242 	p = (u_char*)sa;
1243 	len = sa->sa_len;
1244 	db_printf("[");
1245 	while (len > 0) {
1246 		db_printf("%d", *p);
1247 		p++; len--;
1248 		if (len) db_printf(",");
1249 	}
1250 	db_printf("]\n");
1251 }
1252 static void
1253 db_print_ifa(ifa)
1254 	struct ifaddr *ifa;
1255 {
1256 	if (ifa == 0)
1257 		return;
1258 	db_printf("  ifa_addr=");
1259 	db_print_sa(ifa->ifa_addr);
1260 	db_printf("  ifa_dsta=");
1261 	db_print_sa(ifa->ifa_dstaddr);
1262 	db_printf("  ifa_mask=");
1263 	db_print_sa(ifa->ifa_netmask);
1264 	db_printf("  flags=0x%x,refcnt=%d,metric=%d\n",
1265 			  ifa->ifa_flags,
1266 			  ifa->ifa_refcnt,
1267 			  ifa->ifa_metric);
1268 }
1269 static void
1270 db_print_llinfo(li)
1271 	caddr_t li;
1272 {
1273 	struct llinfo_arp *la;
1274 
1275 	if (li == 0)
1276 		return;
1277 	la = (struct llinfo_arp *)li;
1278 	db_printf("  la_rt=%p la_hold=%p, la_asked=0x%lx\n",
1279 			  la->la_rt, la->la_hold, la->la_asked);
1280 }
1281 /*
1282  * Function to pass to rn_walktree().
1283  * Return non-zero error to abort walk.
1284  */
1285 static int
1286 db_show_radix_node(rn, w)
1287 	struct radix_node *rn;
1288 	void *w;
1289 {
1290 	struct rtentry *rt = (struct rtentry *)rn;
1291 
1292 	db_printf("rtentry=%p", rt);
1293 
1294 	db_printf(" flags=0x%x refcnt=%d use=%ld expire=%ld\n",
1295 			  rt->rt_flags, rt->rt_refcnt,
1296 			  rt->rt_use, rt->rt_expire);
1297 
1298 	db_printf(" key="); db_print_sa(rt_key(rt));
1299 	db_printf(" mask="); db_print_sa(rt_mask(rt));
1300 	db_printf(" gw="); db_print_sa(rt->rt_gateway);
1301 
1302 	db_printf(" ifp=%p ", rt->rt_ifp);
1303 	if (rt->rt_ifp)
1304 		db_printf("(%s)", rt->rt_ifp->if_xname);
1305 	else
1306 		db_printf("(NULL)");
1307 
1308 	db_printf(" ifa=%p\n", rt->rt_ifa);
1309 	db_print_ifa(rt->rt_ifa);
1310 
1311 	db_printf(" genmask="); db_print_sa(rt->rt_genmask);
1312 
1313 	db_printf(" gwroute=%p llinfo=%p\n",
1314 			  rt->rt_gwroute, rt->rt_llinfo);
1315 	db_print_llinfo(rt->rt_llinfo);
1316 
1317 	return (0);
1318 }
1319 /*
1320  * Function to print all the route trees.
1321  * Use this from ddb:  "show arptab"
1322  */
1323 void
1324 db_show_arptab(addr, have_addr, count, modif)
1325 	db_expr_t	addr;
1326 	int		have_addr;
1327 	db_expr_t	count;
1328 	char *		modif;
1329 {
1330 	struct radix_node_head *rnh;
1331 	rnh = rt_tables[AF_INET];
1332 	db_printf("Route tree for AF_INET\n");
1333 	if (rnh == NULL) {
1334 		db_printf(" (not initialized)\n");
1335 		return;
1336 	}
1337 	rn_walktree(rnh, db_show_radix_node, NULL);
1338 	return;
1339 }
1340 #endif
1341 #endif /* INET */
1342 
1343