xref: /netbsd-src/sys/netatalk/aarp.c (revision b1c86f5f087524e68db12794ee9c3e3da1ab17a0)
1 /*	$NetBSD: aarp.c,v 1.34 2009/09/12 20:43:18 tsutsui Exp $	*/
2 
3 /*
4  * Copyright (c) 1990,1991 Regents of The University of Michigan.
5  * All Rights Reserved.
6  *
7  * Permission to use, copy, modify, and distribute this software and
8  * its documentation for any purpose and without fee is hereby granted,
9  * provided that the above copyright notice appears in all copies and
10  * that both that copyright notice and this permission notice appear
11  * in supporting documentation, and that the name of The University
12  * of Michigan not be used in advertising or publicity pertaining to
13  * distribution of the software without specific, written prior
14  * permission. This software is supplied as is without expressed or
15  * implied warranties of any kind.
16  *
17  * This product includes software developed by the University of
18  * California, Berkeley and its contributors.
19  *
20  *	Research Systems Unix Group
21  *	The University of Michigan
22  *	c/o Wesley Craig
23  *	535 W. William Street
24  *	Ann Arbor, Michigan
25  *	+1-313-764-2278
26  *	netatalk@umich.edu
27  */
28 
29 #include <sys/cdefs.h>
30 __KERNEL_RCSID(0, "$NetBSD: aarp.c,v 1.34 2009/09/12 20:43:18 tsutsui Exp $");
31 
32 #include "opt_mbuftrace.h"
33 
34 #include <sys/param.h>
35 #include <sys/socket.h>
36 #include <sys/syslog.h>
37 #include <sys/systm.h>
38 #include <sys/callout.h>
39 #include <sys/proc.h>
40 #include <sys/mbuf.h>
41 #include <sys/time.h>
42 #include <sys/kernel.h>
43 #include <sys/socketvar.h>
44 #include <net/if.h>
45 #include <net/route.h>
46 #include <net/if_ether.h>
47 #include <net/if_dl.h>
48 #include <netinet/in.h>
49 #undef s_net
50 
51 #include <netatalk/at.h>
52 #include <netatalk/at_var.h>
53 #include <netatalk/aarp.h>
54 #include <netatalk/ddp_var.h>
55 #include <netatalk/phase2.h>
56 #include <netatalk/at_extern.h>
57 
58 static struct aarptab *aarptnew(const struct at_addr *);
59 static void aarptfree(struct aarptab *);
60 static void at_aarpinput(struct ifnet *, struct mbuf *);
61 static void aarptimer(void *);
62 static void aarpwhohas(struct ifnet *, const struct sockaddr_at *);
63 
64 #define AARPTAB_BSIZ	9
65 #define AARPTAB_NB	19
66 #define AARPTAB_SIZE	(AARPTAB_BSIZ * AARPTAB_NB)
67 struct aarptab  aarptab[AARPTAB_SIZE];
68 
69 #define AARPTAB_HASH(a) \
70     ((((a).s_net << 8 ) + (a).s_node ) % AARPTAB_NB )
71 
72 #define AARPTAB_LOOK(aat,addr) { \
73     int		n; \
74     aat = &aarptab[ AARPTAB_HASH(addr) * AARPTAB_BSIZ ]; \
75     for ( n = 0; n < AARPTAB_BSIZ; n++, aat++ ) \
76 	if ( aat->aat_ataddr.s_net == (addr).s_net && \
77 	     aat->aat_ataddr.s_node == (addr).s_node ) \
78 	    break; \
79 	if ( n >= AARPTAB_BSIZ ) \
80 	    aat = 0; \
81 }
82 
83 #define AARPT_AGE	(60 * 1)
84 #define AARPT_KILLC	20
85 #define AARPT_KILLI	3
86 
87 const u_char atmulticastaddr[6] = {
88 	0x09, 0x00, 0x07, 0xff, 0xff, 0xff
89 };
90 
91 const u_char at_org_code[3] = {
92 	0x08, 0x00, 0x07
93 };
94 const u_char aarp_org_code[3] = {
95 	0x00, 0x00, 0x00
96 };
97 
98 struct callout aarptimer_callout;
99 #ifdef MBUFTRACE
100 struct mowner aarp_mowner = MOWNER_INIT("atalk", "arp");
101 #endif
102 
103 /*ARGSUSED*/
104 static void
105 aarptimer(void *ignored)
106 {
107 	struct aarptab *aat;
108 	int             i, s;
109 
110 	mutex_enter(softnet_lock);
111 	callout_reset(&aarptimer_callout, AARPT_AGE * hz, aarptimer, NULL);
112 	aat = aarptab;
113 	for (i = 0; i < AARPTAB_SIZE; i++, aat++) {
114 		int killtime = (aat->aat_flags & ATF_COM) ? AARPT_KILLC :
115 		    AARPT_KILLI;
116 		if (aat->aat_flags == 0 || (aat->aat_flags & ATF_PERM))
117 			continue;
118 		if (++aat->aat_timer < killtime)
119 			continue;
120 		s = splnet();
121 		aarptfree(aat);
122 		splx(s);
123 	}
124 	mutex_exit(softnet_lock);
125 }
126 
127 /*
128  * search through the network addresses to find one that includes the given
129  * network.. remember to take netranges into consideration.
130  */
131 struct ifaddr *
132 at_ifawithnet(const struct sockaddr_at *sat, struct ifnet *ifp)
133 {
134 	struct ifaddr  *ifa;
135 	struct sockaddr_at *sat2;
136 	struct netrange *nr;
137 
138 	IFADDR_FOREACH(ifa, ifp) {
139 		if (ifa->ifa_addr->sa_family != AF_APPLETALK)
140 			continue;
141 
142 		sat2 = satosat(ifa->ifa_addr);
143 		if (sat2->sat_addr.s_net == sat->sat_addr.s_net)
144 			break;
145 
146 		nr = (struct netrange *) (sat2->sat_zero);
147 		if ((nr->nr_phase == 2)
148 		    && (ntohs(nr->nr_firstnet) <= ntohs(sat->sat_addr.s_net))
149 		    && (ntohs(nr->nr_lastnet) >= ntohs(sat->sat_addr.s_net)))
150 			break;
151 	}
152 	return ifa;
153 }
154 
155 static void
156 aarpwhohas(struct ifnet *ifp, const struct sockaddr_at *sat)
157 {
158 	struct mbuf    *m;
159 	struct ether_header *eh;
160 	struct ether_aarp *ea;
161 	struct at_ifaddr *aa;
162 	struct llc     *llc;
163 	struct sockaddr sa;
164 
165 	if ((m = m_gethdr(M_DONTWAIT, MT_DATA)) == NULL)
166 		return;
167 
168 	MCLAIM(m, &aarp_mowner);
169 	m->m_len = sizeof(*ea);
170 	m->m_pkthdr.len = sizeof(*ea);
171 	MH_ALIGN(m, sizeof(*ea));
172 
173 	ea = mtod(m, struct ether_aarp *);
174 	memset(ea, 0, sizeof(*ea));
175 
176 	ea->aarp_hrd = htons(AARPHRD_ETHER);
177 	ea->aarp_pro = htons(ETHERTYPE_ATALK);
178 	ea->aarp_hln = sizeof(ea->aarp_sha);
179 	ea->aarp_pln = sizeof(ea->aarp_spu);
180 	ea->aarp_op = htons(AARPOP_REQUEST);
181 	memcpy(ea->aarp_sha, CLLADDR(ifp->if_sadl), sizeof(ea->aarp_sha));
182 
183 	/*
184          * We need to check whether the output ethernet type should
185          * be phase 1 or 2. We have the interface that we'll be sending
186          * the aarp out. We need to find an AppleTalk network on that
187          * interface with the same address as we're looking for. If the
188          * net is phase 2, generate an 802.2 and SNAP header.
189          */
190 	if ((aa = (struct at_ifaddr *) at_ifawithnet(sat, ifp)) == NULL) {
191 		m_freem(m);
192 		return;
193 	}
194 	eh = (struct ether_header *) sa.sa_data;
195 
196 	if (aa->aa_flags & AFA_PHASE2) {
197 		memcpy(eh->ether_dhost, atmulticastaddr,
198 		    sizeof(eh->ether_dhost));
199 		eh->ether_type = 0;	/* if_output will treat as 802 */
200 		M_PREPEND(m, sizeof(struct llc), M_DONTWAIT);
201 		if (!m)
202 			return;
203 
204 		llc = mtod(m, struct llc *);
205 		llc->llc_dsap = llc->llc_ssap = LLC_SNAP_LSAP;
206 		llc->llc_control = LLC_UI;
207 		memcpy(llc->llc_org_code, aarp_org_code, sizeof(aarp_org_code));
208 		llc->llc_ether_type = htons(ETHERTYPE_AARP);
209 
210 		memcpy(ea->aarp_spnet, &AA_SAT(aa)->sat_addr.s_net,
211 		      sizeof(ea->aarp_spnet));
212 		memcpy(ea->aarp_tpnet, &sat->sat_addr.s_net,
213 		      sizeof(ea->aarp_tpnet));
214 		ea->aarp_spnode = AA_SAT(aa)->sat_addr.s_node;
215 		ea->aarp_tpnode = sat->sat_addr.s_node;
216 	} else {
217 		memcpy(eh->ether_dhost, etherbroadcastaddr,
218 		    sizeof(eh->ether_dhost));
219 		eh->ether_type = htons(ETHERTYPE_AARP);
220 
221 		ea->aarp_spa = AA_SAT(aa)->sat_addr.s_node;
222 		ea->aarp_tpa = sat->sat_addr.s_node;
223 	}
224 
225 #ifdef NETATALKDEBUG
226 	printf("aarp: sending request via %u.%u seaking %u.%u\n",
227 	    ntohs(AA_SAT(aa)->sat_addr.s_net), AA_SAT(aa)->sat_addr.s_node,
228 	    ntohs(sat->sat_addr.s_net), sat->sat_addr.s_node);
229 #endif	/* NETATALKDEBUG */
230 
231 	sa.sa_len = sizeof(struct sockaddr);
232 	sa.sa_family = AF_UNSPEC;
233 	(*ifp->if_output) (ifp, m, &sa, NULL);	/* XXX NULL should be routing */
234 						/* information */
235 }
236 
237 int
238 aarpresolve(struct ifnet *ifp, struct mbuf *m,
239     const struct sockaddr_at *destsat, u_char *desten)
240 {
241 	struct at_ifaddr *aa;
242 	struct aarptab *aat;
243 	int             s;
244 
245 	if (at_broadcast(destsat)) {
246 		aa = (struct at_ifaddr *) at_ifawithnet(destsat, ifp);
247 		if (aa == NULL) {
248 			m_freem(m);
249 			return (0);
250 		}
251 		if (aa->aa_flags & AFA_PHASE2)
252 			memcpy(desten, atmulticastaddr,
253 			    sizeof(atmulticastaddr));
254 		else
255 			memcpy(desten, etherbroadcastaddr,
256 			    sizeof(etherbroadcastaddr));
257 		return 1;
258 	}
259 	s = splnet();
260 	AARPTAB_LOOK(aat, destsat->sat_addr);
261 	if (aat == 0) {		/* No entry */
262 		aat = aarptnew(&destsat->sat_addr);
263 		if (aat == 0)
264 			panic("aarpresolve: no free entry");
265 
266 		aat->aat_hold = m;
267 		aarpwhohas(ifp, destsat);
268 		splx(s);
269 		return 0;
270 	}
271 
272 	/* found an entry */
273 	aat->aat_timer = 0;
274 	if (aat->aat_flags & ATF_COM) {	/* entry is COMplete */
275 		memcpy(desten, aat->aat_enaddr, sizeof(aat->aat_enaddr));
276 		splx(s);
277 		return 1;
278 	}
279 
280 	/* entry has not completed */
281 	if (aat->aat_hold)
282 		m_freem(aat->aat_hold);
283 	aat->aat_hold = m;
284 	aarpwhohas(ifp, destsat);
285 	splx(s);
286 
287 	return 0;
288 }
289 
290 void
291 aarpinput(struct ifnet *ifp, struct mbuf *m)
292 {
293 	struct arphdr  *ar;
294 
295 	if (ifp->if_flags & IFF_NOARP)
296 		goto out;
297 
298 	if (m->m_len < sizeof(struct arphdr))
299 		goto out;
300 
301 	ar = mtod(m, struct arphdr *);
302 	if (ntohs(ar->ar_hrd) != AARPHRD_ETHER)
303 		goto out;
304 
305 	if (m->m_len < sizeof(struct arphdr) + 2 * ar->ar_hln + 2 * ar->ar_pln)
306 		goto out;
307 
308 	switch (ntohs(ar->ar_pro)) {
309 	case ETHERTYPE_ATALK:
310 		at_aarpinput(ifp, m);
311 		return;
312 
313 	default:
314 		break;
315 	}
316 
317 out:
318 	m_freem(m);
319 }
320 
321 static void
322 at_aarpinput(struct ifnet *ifp, struct mbuf *m)
323 {
324 	struct ether_aarp *ea;
325 	struct at_ifaddr *aa;
326 	struct ifaddr *ia;
327 	struct aarptab *aat;
328 	struct ether_header *eh;
329 	struct llc     *llc;
330 	struct sockaddr_at sat;
331 	struct sockaddr sa;
332 	struct at_addr  spa, tpa, ma;
333 	int             op;
334 	u_int16_t       net;
335 
336 	ea = mtod(m, struct ether_aarp *);
337 
338 	/* Check to see if from my hardware address */
339 	if (!memcmp(ea->aarp_sha, CLLADDR(ifp->if_sadl), sizeof(ea->aarp_sha))) {
340 		m_freem(m);
341 		return;
342 	}
343 	op = ntohs(ea->aarp_op);
344 	memcpy(&net, ea->aarp_tpnet, sizeof(net));
345 
346 	if (net != 0) {		/* should be ATADDR_ANYNET? */
347 		sat.sat_len = sizeof(struct sockaddr_at);
348 		sat.sat_family = AF_APPLETALK;
349 		sat.sat_addr.s_net = net;
350 		aa = (struct at_ifaddr *) at_ifawithnet(&sat, ifp);
351 		if (aa == NULL) {
352 			m_freem(m);
353 			return;
354 		}
355 		memcpy(&spa.s_net, ea->aarp_spnet, sizeof(spa.s_net));
356 		memcpy(&tpa.s_net, ea->aarp_tpnet, sizeof(tpa.s_net));
357 	} else {
358 		/*
359 		 * Since we don't know the net, we just look for the first
360 		 * phase 1 address on the interface.
361 		 */
362 		IFADDR_FOREACH(ia, ifp) {
363 			aa = (struct at_ifaddr *)ia;
364 			if (AA_SAT(aa)->sat_family == AF_APPLETALK &&
365 			    (aa->aa_flags & AFA_PHASE2) == 0)
366 				break;
367 		}
368 		if (ia == NULL) {
369 			m_freem(m);
370 			return;
371 		}
372 		tpa.s_net = spa.s_net = AA_SAT(aa)->sat_addr.s_net;
373 	}
374 
375 	spa.s_node = ea->aarp_spnode;
376 	tpa.s_node = ea->aarp_tpnode;
377 	ma.s_net = AA_SAT(aa)->sat_addr.s_net;
378 	ma.s_node = AA_SAT(aa)->sat_addr.s_node;
379 
380 	/*
381          * This looks like it's from us.
382          */
383 	if (spa.s_net == ma.s_net && spa.s_node == ma.s_node) {
384 		if (aa->aa_flags & AFA_PROBING) {
385 			/*
386 		         * We're probing, someone either responded to our
387 			 * probe, or probed for the same address we'd like
388 			 * to use. Change the address we're probing for.
389 		         */
390 			callout_stop(&aa->aa_probe_ch);
391 			wakeup(aa);
392 			m_freem(m);
393 			return;
394 		} else if (op != AARPOP_PROBE) {
395 			/*
396 		         * This is not a probe, and we're not probing.
397 			 * This means that someone's saying they have the same
398 			 * source address as the one we're using. Get upset...
399 		         */
400 			log(LOG_ERR, "aarp: duplicate AT address!! %s\n",
401 			    ether_sprintf(ea->aarp_sha));
402 			m_freem(m);
403 			return;
404 		}
405 	}
406 	AARPTAB_LOOK(aat, spa);
407 	if (aat) {
408 		if (op == AARPOP_PROBE) {
409 			/*
410 		         * Someone's probing for spa, deallocate the one we've
411 			 * got, so that if the prober keeps the address, we'll
412 			 * be able to arp for him.
413 		         */
414 			aarptfree(aat);
415 			m_freem(m);
416 			return;
417 		}
418 		memcpy(aat->aat_enaddr, ea->aarp_sha, sizeof(ea->aarp_sha));
419 		aat->aat_flags |= ATF_COM;
420 		if (aat->aat_hold) {
421 			sat.sat_len = sizeof(struct sockaddr_at);
422 			sat.sat_family = AF_APPLETALK;
423 			sat.sat_addr = spa;
424 			(*ifp->if_output)(ifp, aat->aat_hold,
425 			    (struct sockaddr *) & sat, NULL);	/* XXX */
426 			aat->aat_hold = 0;
427 		}
428 	}
429 	if (aat == 0 && tpa.s_net == ma.s_net && tpa.s_node == ma.s_node
430 	    && op != AARPOP_PROBE) {
431 		if ((aat = aarptnew(&spa)) != NULL) {
432 			memcpy(aat->aat_enaddr, ea->aarp_sha,
433 			    sizeof(ea->aarp_sha));
434 			aat->aat_flags |= ATF_COM;
435 		}
436 	}
437 	/*
438          * Don't respond to responses, and never respond if we're
439          * still probing.
440          */
441 	if (tpa.s_net != ma.s_net || tpa.s_node != ma.s_node ||
442 	    op == AARPOP_RESPONSE || (aa->aa_flags & AFA_PROBING)) {
443 		m_freem(m);
444 		return;
445 	}
446 
447 	/*
448 	 * Prepare and send AARP-response.
449 	 */
450 	m->m_len = sizeof(*ea);
451 	m->m_pkthdr.len = sizeof(*ea);
452 	memcpy(ea->aarp_tha, ea->aarp_sha, sizeof(ea->aarp_sha));
453 	memcpy(ea->aarp_sha, CLLADDR(ifp->if_sadl), sizeof(ea->aarp_sha));
454 
455 	/* XXX */
456 	eh = (struct ether_header *) sa.sa_data;
457 	memcpy(eh->ether_dhost, ea->aarp_tha, sizeof(eh->ether_dhost));
458 
459 	if (aa->aa_flags & AFA_PHASE2) {
460 		M_PREPEND(m, sizeof(struct llc), M_DONTWAIT);
461 		if (m == NULL)
462 			return;
463 
464 		llc = mtod(m, struct llc *);
465 		llc->llc_dsap = llc->llc_ssap = LLC_SNAP_LSAP;
466 		llc->llc_control = LLC_UI;
467 		memcpy(llc->llc_org_code, aarp_org_code, sizeof(aarp_org_code));
468 		llc->llc_ether_type = htons(ETHERTYPE_AARP);
469 
470 		memcpy(ea->aarp_tpnet, ea->aarp_spnet, sizeof(ea->aarp_tpnet));
471 		memcpy(ea->aarp_spnet, &ma.s_net, sizeof(ea->aarp_spnet));
472 		eh->ether_type = 0;	/* if_output will treat as 802 */
473 	} else {
474 		eh->ether_type = htons(ETHERTYPE_AARP);
475 	}
476 
477 	ea->aarp_tpnode = ea->aarp_spnode;
478 	ea->aarp_spnode = ma.s_node;
479 	ea->aarp_op = htons(AARPOP_RESPONSE);
480 
481 	sa.sa_len = sizeof(struct sockaddr);
482 	sa.sa_family = AF_UNSPEC;
483 	(*ifp->if_output) (ifp, m, &sa, NULL);	/* XXX */
484 	return;
485 }
486 
487 static void
488 aarptfree(struct aarptab *aat)
489 {
490 
491 	if (aat->aat_hold)
492 		m_freem(aat->aat_hold);
493 	aat->aat_hold = 0;
494 	aat->aat_timer = aat->aat_flags = 0;
495 	aat->aat_ataddr.s_net = 0;
496 	aat->aat_ataddr.s_node = 0;
497 }
498 
499 static struct aarptab *
500 aarptnew(const struct at_addr *addr)
501 {
502 	int             n;
503 	int             oldest = -1;
504 	struct aarptab *aat, *aato = NULL;
505 	static int      first = 1;
506 
507 	if (first) {
508 		first = 0;
509 		callout_init(&aarptimer_callout, 0);
510 		callout_reset(&aarptimer_callout, hz, aarptimer, NULL);
511 		MOWNER_ATTACH(&aarp_mowner);
512 	}
513 	aat = &aarptab[AARPTAB_HASH(*addr) * AARPTAB_BSIZ];
514 	for (n = 0; n < AARPTAB_BSIZ; n++, aat++) {
515 		if (aat->aat_flags == 0)
516 			goto out;
517 		if (aat->aat_flags & ATF_PERM)
518 			continue;
519 		if ((int) aat->aat_timer > oldest) {
520 			oldest = aat->aat_timer;
521 			aato = aat;
522 		}
523 	}
524 	if (aato == NULL)
525 		return (NULL);
526 	aat = aato;
527 	aarptfree(aat);
528 out:
529 	aat->aat_ataddr = *addr;
530 	aat->aat_flags = ATF_INUSE;
531 	return (aat);
532 }
533 
534 
535 void
536 aarpprobe(void *arp)
537 {
538 	struct mbuf    *m;
539 	struct ether_header *eh;
540 	struct ether_aarp *ea;
541 	struct ifaddr *ia;
542 	struct at_ifaddr *aa;
543 	struct llc     *llc;
544 	struct sockaddr sa;
545 	struct ifnet   *ifp = arp;
546 
547 	mutex_enter(softnet_lock);
548 
549 	/*
550          * We need to check whether the output ethernet type should
551          * be phase 1 or 2. We have the interface that we'll be sending
552          * the aarp out. We need to find an AppleTalk network on that
553          * interface with the same address as we're looking for. If the
554          * net is phase 2, generate an 802.2 and SNAP header.
555          */
556 	IFADDR_FOREACH(ia, ifp) {
557 		aa = (struct at_ifaddr *)ia;
558 		if (AA_SAT(aa)->sat_family == AF_APPLETALK &&
559 		    (aa->aa_flags & AFA_PROBING))
560 			break;
561 	}
562 	if (ia == NULL) {	/* serious error XXX */
563 		printf("aarpprobe why did this happen?!\n");
564 		mutex_exit(softnet_lock);
565 		return;
566 	}
567 	if (aa->aa_probcnt <= 0) {
568 		aa->aa_flags &= ~AFA_PROBING;
569 		wakeup(aa);
570 		mutex_exit(softnet_lock);
571 		return;
572 	} else {
573 		callout_reset(&aa->aa_probe_ch, hz / 5, aarpprobe, arp);
574 	}
575 
576 	if ((m = m_gethdr(M_DONTWAIT, MT_DATA)) == NULL) {
577 		mutex_exit(softnet_lock);
578 		return;
579 	}
580 
581 	MCLAIM(m, &aarp_mowner);
582 	m->m_len = sizeof(*ea);
583 	m->m_pkthdr.len = sizeof(*ea);
584 	MH_ALIGN(m, sizeof(*ea));
585 
586 	ea = mtod(m, struct ether_aarp *);
587 	memset(ea, 0, sizeof(*ea));
588 
589 	ea->aarp_hrd = htons(AARPHRD_ETHER);
590 	ea->aarp_pro = htons(ETHERTYPE_ATALK);
591 	ea->aarp_hln = sizeof(ea->aarp_sha);
592 	ea->aarp_pln = sizeof(ea->aarp_spu);
593 	ea->aarp_op = htons(AARPOP_PROBE);
594 	memcpy(ea->aarp_sha, CLLADDR(ifp->if_sadl), sizeof(ea->aarp_sha));
595 
596 	eh = (struct ether_header *) sa.sa_data;
597 
598 	if (aa->aa_flags & AFA_PHASE2) {
599 		memcpy(eh->ether_dhost, atmulticastaddr,
600 		    sizeof(eh->ether_dhost));
601 		eh->ether_type = 0;	/* if_output will treat as 802 */
602 		M_PREPEND(m, sizeof(struct llc), M_DONTWAIT);
603 		if (!m) {
604 			mutex_exit(softnet_lock);
605 			return;
606 		}
607 
608 		llc = mtod(m, struct llc *);
609 		llc->llc_dsap = llc->llc_ssap = LLC_SNAP_LSAP;
610 		llc->llc_control = LLC_UI;
611 		memcpy(llc->llc_org_code, aarp_org_code, sizeof(aarp_org_code));
612 		llc->llc_ether_type = htons(ETHERTYPE_AARP);
613 
614 		memcpy(ea->aarp_spnet, &AA_SAT(aa)->sat_addr.s_net,
615 		      sizeof(ea->aarp_spnet));
616 		memcpy(ea->aarp_tpnet, &AA_SAT(aa)->sat_addr.s_net,
617 		      sizeof(ea->aarp_tpnet));
618 		ea->aarp_spnode = ea->aarp_tpnode =
619 		    AA_SAT(aa)->sat_addr.s_node;
620 	} else {
621 		memcpy(eh->ether_dhost, etherbroadcastaddr,
622 		    sizeof(eh->ether_dhost));
623 		eh->ether_type = htons(ETHERTYPE_AARP);
624 		ea->aarp_spa = ea->aarp_tpa = AA_SAT(aa)->sat_addr.s_node;
625 	}
626 
627 #ifdef NETATALKDEBUG
628 	printf("aarp: sending probe for %u.%u\n",
629 	       ntohs(AA_SAT(aa)->sat_addr.s_net),
630 	       AA_SAT(aa)->sat_addr.s_node);
631 #endif	/* NETATALKDEBUG */
632 
633 	sa.sa_len = sizeof(struct sockaddr);
634 	sa.sa_family = AF_UNSPEC;
635 	(*ifp->if_output) (ifp, m, &sa, NULL);	/* XXX */
636 	aa->aa_probcnt--;
637 	mutex_exit(softnet_lock);
638 }
639 
640 void
641 aarp_clean(void)
642 {
643 	struct aarptab *aat;
644 	int             i;
645 
646 	callout_stop(&aarptimer_callout);
647 	for (i = 0, aat = aarptab; i < AARPTAB_SIZE; i++, aat++)
648 		if (aat->aat_hold)
649 			m_freem(aat->aat_hold);
650 }
651