if_arp.c revision 1.92 1 /* $NetBSD: if_arp.c,v 1.92 2003/02/26 06:31:14 matt 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 <sys/cdefs.h>
82 __KERNEL_RCSID(0, "$NetBSD: if_arp.c,v 1.92 2003/02/26 06:31:14 matt Exp $");
83
84 #include "opt_ddb.h"
85 #include "opt_inet.h"
86
87 #ifdef INET
88
89 #include "bridge.h"
90
91 #include <sys/param.h>
92 #include <sys/systm.h>
93 #include <sys/callout.h>
94 #include <sys/malloc.h>
95 #include <sys/mbuf.h>
96 #include <sys/socket.h>
97 #include <sys/time.h>
98 #include <sys/kernel.h>
99 #include <sys/errno.h>
100 #include <sys/ioctl.h>
101 #include <sys/syslog.h>
102 #include <sys/proc.h>
103 #include <sys/protosw.h>
104 #include <sys/domain.h>
105
106 #include <net/ethertypes.h>
107 #include <net/if.h>
108 #include <net/if_dl.h>
109 #include <net/if_token.h>
110 #include <net/if_types.h>
111 #include <net/route.h>
112
113 #include <netinet/in.h>
114 #include <netinet/in_systm.h>
115 #include <netinet/in_var.h>
116 #include <netinet/ip.h>
117 #include <netinet/if_inarp.h>
118
119 #include "loop.h"
120 #include "arc.h"
121 #if NARC > 0
122 #include <net/if_arc.h>
123 #endif
124 #include "fddi.h"
125 #if NFDDI > 0
126 #include <net/if_fddi.h>
127 #endif
128 #include "token.h"
129
130 #define SIN(s) ((struct sockaddr_in *)s)
131 #define SDL(s) ((struct sockaddr_dl *)s)
132 #define SRP(s) ((struct sockaddr_inarp *)s)
133
134 /*
135 * ARP trailer negotiation. Trailer protocol is not IP specific,
136 * but ARP request/response use IP addresses.
137 */
138 #define ETHERTYPE_IPTRAILERS ETHERTYPE_TRAIL
139
140 /* timer values */
141 int arpt_prune = (5*60*1); /* walk list every 5 minutes */
142 int arpt_keep = (20*60); /* once resolved, good for 20 more minutes */
143 int arpt_down = 20; /* once declared down, don't send for 20 secs */
144 #define rt_expire rt_rmx.rmx_expire
145
146 extern struct domain arpdomain;
147
148 static void arprequest __P((struct ifnet *,
149 struct in_addr *, struct in_addr *, u_int8_t *));
150 static void arptfree __P((struct llinfo_arp *));
151 static void arptimer __P((void *));
152 static struct llinfo_arp *arplookup __P((struct mbuf *, struct in_addr *,
153 int, int));
154 static void in_arpinput __P((struct mbuf *));
155
156 #if NLOOP > 0
157 extern struct ifnet loif[NLOOP];
158 #endif
159 LIST_HEAD(, llinfo_arp) llinfo_arp;
160 struct ifqueue arpintrq = {0, 0, 0, 50};
161 int arp_inuse, arp_allocated, arp_intimer;
162 int arp_maxtries = 5;
163 int useloopback = 1; /* use loopback interface for local traffic */
164 int arpinit_done = 0;
165
166 struct arpstat arpstat;
167 struct callout arptimer_ch;
168
169
170 /* revarp state */
171 static struct in_addr myip, srv_ip;
172 static int myip_initialized = 0;
173 static int revarp_in_progress = 0;
174 static struct ifnet *myip_ifp = NULL;
175
176 #ifdef DDB
177 static void db_print_sa __P((struct sockaddr *));
178 static void db_print_ifa __P((struct ifaddr *));
179 static void db_print_llinfo __P((caddr_t));
180 static int db_show_radix_node __P((struct radix_node *, void *));
181 #endif
182
183 /*
184 * this should be elsewhere.
185 */
186
187 static char *
188 lla_snprintf __P((u_int8_t *, int));
189
190 static char *
191 lla_snprintf(adrp, len)
192 u_int8_t *adrp;
193 int len;
194 {
195 #define NUMBUFS 3
196 static char buf[NUMBUFS][16*3];
197 static int bnum = 0;
198 static const char hexdigits[] = {
199 '0','1','2','3','4','5','6','7',
200 '8','9','a','b','c','d','e','f'
201 };
202
203 int i;
204 char *p;
205
206 p = buf[bnum];
207
208 *p++ = hexdigits[(*adrp)>>4];
209 *p++ = hexdigits[(*adrp++)&0xf];
210
211 for (i=1; i<len && i<16; i++) {
212 *p++ = ':';
213 *p++ = hexdigits[(*adrp)>>4];
214 *p++ = hexdigits[(*adrp++)&0xf];
215 }
216
217 *p = 0;
218 p = buf[bnum];
219 bnum = (bnum + 1) % NUMBUFS;
220 return p;
221 }
222
223 struct protosw arpsw[] = {
224 { 0, 0, 0, 0,
225 0, 0, 0, 0,
226 0,
227 0, 0, 0, arp_drain,
228 }
229 };
230
231
232 struct domain arpdomain =
233 { PF_ARP, "arp", 0, 0, 0,
234 arpsw, &arpsw[sizeof(arpsw)/sizeof(arpsw[0])]
235 };
236
237 /*
238 * ARP table locking.
239 *
240 * to prevent lossage vs. the arp_drain routine (which may be called at
241 * any time, including in a device driver context), we do two things:
242 *
243 * 1) manipulation of la->la_hold is done at splnet() (for all of
244 * about two instructions).
245 *
246 * 2) manipulation of the arp table's linked list is done under the
247 * protection of the ARP_LOCK; if arp_drain() or arptimer is called
248 * while the arp table is locked, we punt and try again later.
249 */
250
251 static int arp_locked;
252 static __inline int arp_lock_try __P((int));
253 static __inline void arp_unlock __P((void));
254
255 static __inline int
256 arp_lock_try(int recurse)
257 {
258 int s;
259
260 /*
261 * Use splvm() -- we're blocking things that would cause
262 * mbuf allocation.
263 */
264 s = splvm();
265 if (!recurse && arp_locked) {
266 splx(s);
267 return (0);
268 }
269 arp_locked++;
270 splx(s);
271 return (1);
272 }
273
274 static __inline void
275 arp_unlock()
276 {
277 int s;
278
279 s = splvm();
280 arp_locked--;
281 splx(s);
282 }
283
284 #ifdef DIAGNOSTIC
285 #define ARP_LOCK(recurse) \
286 do { \
287 if (arp_lock_try(recurse) == 0) { \
288 printf("%s:%d: arp already locked\n", __FILE__, __LINE__); \
289 panic("arp_lock"); \
290 } \
291 } while (/*CONSTCOND*/ 0)
292 #define ARP_LOCK_CHECK() \
293 do { \
294 if (arp_locked == 0) { \
295 printf("%s:%d: arp lock not held\n", __FILE__, __LINE__); \
296 panic("arp lock check"); \
297 } \
298 } while (/*CONSTCOND*/ 0)
299 #else
300 #define ARP_LOCK(x) (void) arp_lock_try(x)
301 #define ARP_LOCK_CHECK() /* nothing */
302 #endif
303
304 #define ARP_UNLOCK() arp_unlock()
305
306 /*
307 * ARP protocol drain routine. Called when memory is in short supply.
308 * Called at splvm();
309 */
310
311 void
312 arp_drain()
313 {
314 struct llinfo_arp *la, *nla;
315 int count = 0;
316 struct mbuf *mold;
317
318 if (arp_lock_try(0) == 0) {
319 printf("arp_drain: locked; punting\n");
320 return;
321 }
322
323 for (la = LIST_FIRST(&llinfo_arp); la != 0; la = nla) {
324 nla = LIST_NEXT(la, la_list);
325
326 mold = la->la_hold;
327 la->la_hold = 0;
328
329 if (mold) {
330 m_freem(mold);
331 count++;
332 }
333 }
334 ARP_UNLOCK();
335 arpstat.as_dfrdropped += count;
336 }
337
338
339 /*
340 * Timeout routine. Age arp_tab entries periodically.
341 */
342 /* ARGSUSED */
343 static void
344 arptimer(arg)
345 void *arg;
346 {
347 int s;
348 struct llinfo_arp *la, *nla;
349
350 s = splsoftnet();
351
352 if (arp_lock_try(0) == 0) {
353 /* get it later.. */
354 splx(s);
355 return;
356 }
357
358 callout_reset(&arptimer_ch, arpt_prune * hz, arptimer, NULL);
359 for (la = LIST_FIRST(&llinfo_arp); la != 0; la = nla) {
360 struct rtentry *rt = la->la_rt;
361
362 nla = LIST_NEXT(la, la_list);
363 if (rt->rt_expire && rt->rt_expire <= time.tv_sec)
364 arptfree(la); /* timer has expired; clear */
365 }
366
367 ARP_UNLOCK();
368
369 splx(s);
370 }
371
372 /*
373 * Parallel to llc_rtrequest.
374 */
375 void
376 arp_rtrequest(req, rt, info)
377 int req;
378 struct rtentry *rt;
379 struct rt_addrinfo *info;
380 {
381 struct sockaddr *gate = rt->rt_gateway;
382 struct llinfo_arp *la = (struct llinfo_arp *)rt->rt_llinfo;
383 static struct sockaddr_dl null_sdl = {sizeof(null_sdl), AF_LINK};
384 size_t allocsize;
385 struct mbuf *mold;
386 int s;
387 struct in_ifaddr *ia;
388 struct ifaddr *ifa;
389
390 if (!arpinit_done) {
391 arpinit_done = 1;
392 /*
393 * We generate expiration times from time.tv_sec
394 * so avoid accidently creating permanent routes.
395 */
396 if (time.tv_sec == 0) {
397 time.tv_sec++;
398 }
399 callout_init(&arptimer_ch);
400 callout_reset(&arptimer_ch, hz, arptimer, NULL);
401 }
402
403 if ((rt->rt_flags & RTF_GATEWAY) != 0) {
404 if (req != RTM_ADD)
405 return;
406
407 /*
408 * linklayers with particular link MTU limitation.
409 */
410 switch(rt->rt_ifp->if_type) {
411 #if NFDDI > 0
412 case IFT_FDDI:
413 if (rt->rt_ifp->if_mtu > FDDIIPMTU)
414 rt->rt_rmx.rmx_mtu = FDDIIPMTU;
415 break;
416 #endif
417 #if NARC > 0
418 case IFT_ARCNET:
419 {
420 int arcipifmtu;
421
422 if (rt->rt_ifp->if_flags & IFF_LINK0)
423 arcipifmtu = arc_ipmtu;
424 else
425 arcipifmtu = ARCMTU;
426 if (rt->rt_ifp->if_mtu > arcipifmtu)
427 rt->rt_rmx.rmx_mtu = arcipifmtu;
428 break;
429 }
430 #endif
431 }
432 return;
433 }
434
435 ARP_LOCK(1); /* we may already be locked here. */
436
437 switch (req) {
438
439 case RTM_ADD:
440 /*
441 * XXX: If this is a manually added route to interface
442 * such as older version of routed or gated might provide,
443 * restore cloning bit.
444 */
445 if ((rt->rt_flags & RTF_HOST) == 0 &&
446 SIN(rt_mask(rt))->sin_addr.s_addr != 0xffffffff)
447 rt->rt_flags |= RTF_CLONING;
448 if (rt->rt_flags & RTF_CLONING) {
449 /*
450 * Case 1: This route should come from a route to iface.
451 */
452 rt_setgate(rt, rt_key(rt),
453 (struct sockaddr *)&null_sdl);
454 gate = rt->rt_gateway;
455 SDL(gate)->sdl_type = rt->rt_ifp->if_type;
456 SDL(gate)->sdl_index = rt->rt_ifp->if_index;
457 /*
458 * Give this route an expiration time, even though
459 * it's a "permanent" route, so that routes cloned
460 * from it do not need their expiration time set.
461 */
462 rt->rt_expire = time.tv_sec;
463 /*
464 * linklayers with particular link MTU limitation.
465 */
466 switch (rt->rt_ifp->if_type) {
467 #if NFDDI > 0
468 case IFT_FDDI:
469 if ((rt->rt_rmx.rmx_locks & RTV_MTU) == 0 &&
470 (rt->rt_rmx.rmx_mtu > FDDIIPMTU ||
471 (rt->rt_rmx.rmx_mtu == 0 &&
472 rt->rt_ifp->if_mtu > FDDIIPMTU)))
473 rt->rt_rmx.rmx_mtu = FDDIIPMTU;
474 break;
475 #endif
476 #if NARC > 0
477 case IFT_ARCNET:
478 {
479 int arcipifmtu;
480 if (rt->rt_ifp->if_flags & IFF_LINK0)
481 arcipifmtu = arc_ipmtu;
482 else
483 arcipifmtu = ARCMTU;
484
485 if ((rt->rt_rmx.rmx_locks & RTV_MTU) == 0 &&
486 (rt->rt_rmx.rmx_mtu > arcipifmtu ||
487 (rt->rt_rmx.rmx_mtu == 0 &&
488 rt->rt_ifp->if_mtu > arcipifmtu)))
489 rt->rt_rmx.rmx_mtu = arcipifmtu;
490 break;
491 }
492 #endif
493 }
494 break;
495 }
496 /* Announce a new entry if requested. */
497 if (rt->rt_flags & RTF_ANNOUNCE)
498 arprequest(rt->rt_ifp,
499 &SIN(rt_key(rt))->sin_addr,
500 &SIN(rt_key(rt))->sin_addr,
501 (u_char *)LLADDR(SDL(gate)));
502 /*FALLTHROUGH*/
503 case RTM_RESOLVE:
504 if (gate->sa_family != AF_LINK ||
505 gate->sa_len < sizeof(null_sdl)) {
506 log(LOG_DEBUG, "arp_rtrequest: bad gateway value\n");
507 break;
508 }
509 SDL(gate)->sdl_type = rt->rt_ifp->if_type;
510 SDL(gate)->sdl_index = rt->rt_ifp->if_index;
511 if (la != 0)
512 break; /* This happens on a route change */
513 /*
514 * Case 2: This route may come from cloning, or a manual route
515 * add with a LL address.
516 */
517 switch (SDL(gate)->sdl_type) {
518 #if NTOKEN > 0
519 case IFT_ISO88025:
520 allocsize = sizeof(*la) + sizeof(struct token_rif);
521 break;
522 #endif /* NTOKEN > 0 */
523 default:
524 allocsize = sizeof(*la);
525 }
526 R_Malloc(la, struct llinfo_arp *, allocsize);
527 rt->rt_llinfo = (caddr_t)la;
528 if (la == 0) {
529 log(LOG_DEBUG, "arp_rtrequest: malloc failed\n");
530 break;
531 }
532 arp_inuse++, arp_allocated++;
533 Bzero(la, allocsize);
534 la->la_rt = rt;
535 rt->rt_flags |= RTF_LLINFO;
536 LIST_INSERT_HEAD(&llinfo_arp, la, la_list);
537
538 INADDR_TO_IA(SIN(rt_key(rt))->sin_addr, ia);
539 while (ia && ia->ia_ifp != rt->rt_ifp)
540 NEXT_IA_WITH_SAME_ADDR(ia);
541 if (ia) {
542 /*
543 * This test used to be
544 * if (loif.if_flags & IFF_UP)
545 * It allowed local traffic to be forced through
546 * the hardware by configuring the loopback down.
547 * However, it causes problems during network
548 * configuration for boards that can't receive
549 * packets they send. It is now necessary to clear
550 * "useloopback" and remove the route to force
551 * traffic out to the hardware.
552 *
553 * In 4.4BSD, the above "if" statement checked
554 * rt->rt_ifa against rt_key(rt). It was changed
555 * to the current form so that we can provide a
556 * better support for multiple IPv4 addresses on a
557 * interface.
558 */
559 rt->rt_expire = 0;
560 Bcopy(LLADDR(rt->rt_ifp->if_sadl),
561 LLADDR(SDL(gate)),
562 SDL(gate)->sdl_alen = rt->rt_ifp->if_addrlen);
563 #if NLOOP > 0
564 if (useloopback)
565 rt->rt_ifp = &loif[0];
566 #endif
567 /*
568 * make sure to set rt->rt_ifa to the interface
569 * address we are using, otherwise we will have trouble
570 * with source address selection.
571 */
572 ifa = &ia->ia_ifa;
573 if (ifa != rt->rt_ifa) {
574 IFAFREE(rt->rt_ifa);
575 IFAREF(ifa);
576 rt->rt_ifa = ifa;
577 }
578 }
579 break;
580
581 case RTM_DELETE:
582 if (la == 0)
583 break;
584 arp_inuse--;
585 LIST_REMOVE(la, la_list);
586 rt->rt_llinfo = 0;
587 rt->rt_flags &= ~RTF_LLINFO;
588
589 s = splnet();
590 mold = la->la_hold;
591 la->la_hold = 0;
592 splx(s);
593
594 if (mold)
595 m_freem(mold);
596
597 Free((caddr_t)la);
598 }
599 ARP_UNLOCK();
600 }
601
602 /*
603 * Broadcast an ARP request. Caller specifies:
604 * - arp header source ip address
605 * - arp header target ip address
606 * - arp header source ethernet address
607 */
608 static void
609 arprequest(ifp, sip, tip, enaddr)
610 struct ifnet *ifp;
611 struct in_addr *sip, *tip;
612 u_int8_t *enaddr;
613 {
614 struct mbuf *m;
615 struct arphdr *ah;
616 struct sockaddr sa;
617
618 if ((m = m_gethdr(M_DONTWAIT, MT_DATA)) == NULL)
619 return;
620 MCLAIM(m, &arpdomain.dom_mowner);
621 switch (ifp->if_type) {
622 case IFT_IEEE1394:
623 m->m_len = sizeof(*ah) + 2 * sizeof(struct in_addr) +
624 ifp->if_addrlen;
625 break;
626 default:
627 m->m_len = sizeof(*ah) + 2 * sizeof(struct in_addr) +
628 2 * ifp->if_addrlen;
629 break;
630 }
631 m->m_pkthdr.len = m->m_len;
632 MH_ALIGN(m, m->m_len);
633 ah = mtod(m, struct arphdr *);
634 bzero((caddr_t)ah, m->m_len);
635 switch (ifp->if_type) {
636 case IFT_IEEE1394: /* RFC2734 */
637 /* fill it now for ar_tpa computation */
638 ah->ar_hrd = htons(ARPHRD_IEEE1394);
639 break;
640 default:
641 /* ifp->if_output will fill ar_hrd */
642 break;
643 }
644 ah->ar_pro = htons(ETHERTYPE_IP);
645 ah->ar_hln = ifp->if_addrlen; /* hardware address length */
646 ah->ar_pln = sizeof(struct in_addr); /* protocol address length */
647 ah->ar_op = htons(ARPOP_REQUEST);
648 bcopy((caddr_t)enaddr, (caddr_t)ar_sha(ah), ah->ar_hln);
649 bcopy((caddr_t)sip, (caddr_t)ar_spa(ah), ah->ar_pln);
650 bcopy((caddr_t)tip, (caddr_t)ar_tpa(ah), ah->ar_pln);
651 sa.sa_family = AF_ARP;
652 sa.sa_len = 2;
653 m->m_flags |= M_BCAST;
654 arpstat.as_sndtotal++;
655 arpstat.as_sndrequest++;
656 (*ifp->if_output)(ifp, m, &sa, (struct rtentry *)0);
657 }
658
659 /*
660 * Resolve an IP address into an ethernet address. If success,
661 * desten is filled in. If there is no entry in arptab,
662 * set one up and broadcast a request for the IP address.
663 * Hold onto this mbuf and resend it once the address
664 * is finally resolved. A return value of 1 indicates
665 * that desten has been filled in and the packet should be sent
666 * normally; a 0 return indicates that the packet has been
667 * taken over here, either now or for later transmission.
668 */
669 int
670 arpresolve(ifp, rt, m, dst, desten)
671 struct ifnet *ifp;
672 struct rtentry *rt;
673 struct mbuf *m;
674 struct sockaddr *dst;
675 u_char *desten;
676 {
677 struct llinfo_arp *la;
678 struct sockaddr_dl *sdl;
679 struct mbuf *mold;
680 int s;
681
682 if (rt)
683 la = (struct llinfo_arp *)rt->rt_llinfo;
684 else {
685 if ((la = arplookup(m, &SIN(dst)->sin_addr, 1, 0)) != NULL)
686 rt = la->la_rt;
687 }
688 if (la == 0 || rt == 0) {
689 arpstat.as_allocfail++;
690 log(LOG_DEBUG,
691 "arpresolve: can't allocate llinfo on %s for %s\n",
692 ifp->if_xname, in_fmtaddr(SIN(dst)->sin_addr));
693 m_freem(m);
694 return (0);
695 }
696 sdl = SDL(rt->rt_gateway);
697 /*
698 * Check the address family and length is valid, the address
699 * is resolved; otherwise, try to resolve.
700 */
701 if ((rt->rt_expire == 0 || rt->rt_expire > time.tv_sec) &&
702 sdl->sdl_family == AF_LINK && sdl->sdl_alen != 0) {
703 bcopy(LLADDR(sdl), desten,
704 min(sdl->sdl_alen, ifp->if_addrlen));
705 return 1;
706 }
707 /*
708 * There is an arptab entry, but no ethernet address
709 * response yet. Replace the held mbuf with this
710 * latest one.
711 */
712
713 arpstat.as_dfrtotal++;
714 s = splnet();
715 mold = la->la_hold;
716 la->la_hold = m;
717 splx(s);
718
719 if (mold) {
720 arpstat.as_dfrdropped++;
721 m_freem(mold);
722 }
723
724 /*
725 * Re-send the ARP request when appropriate.
726 */
727 #ifdef DIAGNOSTIC
728 if (rt->rt_expire == 0) {
729 /* This should never happen. (Should it? -gwr) */
730 printf("arpresolve: unresolved and rt_expire == 0\n");
731 /* Set expiration time to now (expired). */
732 rt->rt_expire = time.tv_sec;
733 }
734 #endif
735 if (rt->rt_expire) {
736 rt->rt_flags &= ~RTF_REJECT;
737 if (la->la_asked == 0 || rt->rt_expire != time.tv_sec) {
738 rt->rt_expire = time.tv_sec;
739 if (la->la_asked++ < arp_maxtries)
740 arprequest(ifp,
741 &SIN(rt->rt_ifa->ifa_addr)->sin_addr,
742 &SIN(dst)->sin_addr,
743 LLADDR(ifp->if_sadl));
744 else {
745 rt->rt_flags |= RTF_REJECT;
746 rt->rt_expire += arpt_down;
747 la->la_asked = 0;
748 }
749 }
750 }
751 return (0);
752 }
753
754 /*
755 * Common length and type checks are done here,
756 * then the protocol-specific routine is called.
757 */
758 void
759 arpintr()
760 {
761 struct mbuf *m;
762 struct arphdr *ar;
763 int s;
764 int arplen;
765
766 while (arpintrq.ifq_head) {
767 s = splnet();
768 IF_DEQUEUE(&arpintrq, m);
769 splx(s);
770 if (m == 0 || (m->m_flags & M_PKTHDR) == 0)
771 panic("arpintr");
772
773 MCLAIM(m, &arpdomain.dom_mowner);
774 arpstat.as_rcvtotal++;
775
776 /*
777 * First, make sure we have at least struct arphdr.
778 */
779 if (m->m_len < sizeof(struct arphdr) ||
780 (ar = mtod(m, struct arphdr *)) == NULL)
781 goto badlen;
782
783 switch (m->m_pkthdr.rcvif->if_type) {
784 case IFT_IEEE1394:
785 arplen = sizeof(struct arphdr) +
786 ar->ar_hln + 2 * ar->ar_pln;
787 break;
788 default:
789 arplen = sizeof(struct arphdr) +
790 2 * ar->ar_hln + 2 * ar->ar_pln;
791 break;
792 }
793
794 if (/* XXX ntohs(ar->ar_hrd) == ARPHRD_ETHER && */
795 m->m_len >= arplen)
796 switch (ntohs(ar->ar_pro)) {
797 case ETHERTYPE_IP:
798 case ETHERTYPE_IPTRAILERS:
799 in_arpinput(m);
800 continue;
801 default:
802 arpstat.as_rcvbadproto++;
803 }
804 else {
805 badlen:
806 arpstat.as_rcvbadlen++;
807 }
808 m_freem(m);
809 }
810 }
811
812 /*
813 * ARP for Internet protocols on 10 Mb/s Ethernet.
814 * Algorithm is that given in RFC 826.
815 * In addition, a sanity check is performed on the sender
816 * protocol address, to catch impersonators.
817 * We no longer handle negotiations for use of trailer protocol:
818 * Formerly, ARP replied for protocol type ETHERTYPE_TRAIL sent
819 * along with IP replies if we wanted trailers sent to us,
820 * and also sent them in response to IP replies.
821 * This allowed either end to announce the desire to receive
822 * trailer packets.
823 * We no longer reply to requests for ETHERTYPE_TRAIL protocol either,
824 * but formerly didn't normally send requests.
825 */
826 static void
827 in_arpinput(m)
828 struct mbuf *m;
829 {
830 struct arphdr *ah;
831 struct ifnet *ifp = m->m_pkthdr.rcvif;
832 struct llinfo_arp *la = 0;
833 struct rtentry *rt;
834 struct in_ifaddr *ia;
835 #if NBRIDGE > 0
836 struct in_ifaddr *bridge_ia = NULL;
837 #endif
838 struct sockaddr_dl *sdl;
839 struct sockaddr sa;
840 struct in_addr isaddr, itaddr, myaddr;
841 int op;
842 struct mbuf *mold;
843 int s;
844
845 ah = mtod(m, struct arphdr *);
846 op = ntohs(ah->ar_op);
847
848 /*
849 * Fix up ah->ar_hrd if necessary, before using ar_tha() or
850 * ar_tpa().
851 */
852 switch (ifp->if_type) {
853 case IFT_IEEE1394:
854 if (ntohs(ah->ar_hrd) == ARPHRD_IEEE1394)
855 ;
856 else {
857 /* XXX this is to make sure we compute ar_tha right */
858 /* XXX check ar_hrd more strictly? */
859 ah->ar_hrd = htons(ARPHRD_IEEE1394);
860 }
861 break;
862 default:
863 /* XXX check ar_hrd? */
864 break;
865 }
866
867 bcopy((caddr_t)ar_spa(ah), (caddr_t)&isaddr, sizeof (isaddr));
868 bcopy((caddr_t)ar_tpa(ah), (caddr_t)&itaddr, sizeof (itaddr));
869
870 if (m->m_flags & (M_BCAST|M_MCAST))
871 arpstat.as_rcvmcast++;
872
873 /*
874 * If the target IP address is zero, ignore the packet.
875 * This prevents the code below from tring to answer
876 * when we are using IP address zero (booting).
877 */
878 if (in_nullhost(itaddr)) {
879 arpstat.as_rcvzerotpa++;
880 goto out;
881 }
882
883 /*
884 * If the source IP address is zero, this is most likely a
885 * confused host trying to use IP address zero. (Windoze?)
886 * XXX: Should we bother trying to reply to these?
887 */
888 if (in_nullhost(isaddr)) {
889 arpstat.as_rcvzerospa++;
890 goto out;
891 }
892
893 /*
894 * Search for a matching interface address
895 * or any address on the interface to use
896 * as a dummy address in the rest of this function
897 */
898 INADDR_TO_IA(itaddr, ia);
899 while (ia != NULL) {
900 if (ia->ia_ifp == m->m_pkthdr.rcvif)
901 break;
902
903 #if NBRIDGE > 0
904 /*
905 * If the interface we received the packet on
906 * is part of a bridge, check to see if we need
907 * to "bridge" the packet to ourselves at this
908 * layer. Note we still prefer a perfect match,
909 * but allow this weaker match if necessary.
910 */
911 if (m->m_pkthdr.rcvif->if_bridge != NULL &&
912 m->m_pkthdr.rcvif->if_bridge == ia->ia_ifp->if_bridge)
913 bridge_ia = ia;
914 #endif /* NBRIDGE > 0 */
915
916 NEXT_IA_WITH_SAME_ADDR(ia);
917 }
918
919 #if NBRIDGE > 0
920 if (ia == NULL && bridge_ia != NULL) {
921 ia = bridge_ia;
922 ifp = bridge_ia->ia_ifp;
923 }
924 #endif
925
926 if (ia == NULL) {
927 INADDR_TO_IA(isaddr, ia);
928 while ((ia != NULL) && ia->ia_ifp != m->m_pkthdr.rcvif)
929 NEXT_IA_WITH_SAME_ADDR(ia);
930
931 if (ia == NULL) {
932 IFP_TO_IA(ifp, ia);
933 if (ia == NULL) {
934 arpstat.as_rcvnoint++;
935 goto out;
936 }
937 }
938 }
939
940 myaddr = ia->ia_addr.sin_addr;
941
942 /* XXX checks for bridge case? */
943 if (!bcmp((caddr_t)ar_sha(ah), LLADDR(ifp->if_sadl),
944 ifp->if_addrlen)) {
945 arpstat.as_rcvlocalsha++;
946 goto out; /* it's from me, ignore it. */
947 }
948
949 /* XXX checks for bridge case? */
950 if (!bcmp((caddr_t)ar_sha(ah), (caddr_t)ifp->if_broadcastaddr,
951 ifp->if_addrlen)) {
952 arpstat.as_rcvbcastsha++;
953 log(LOG_ERR,
954 "%s: arp: link address is broadcast for IP address %s!\n",
955 ifp->if_xname, in_fmtaddr(isaddr));
956 goto out;
957 }
958
959 if (in_hosteq(isaddr, myaddr)) {
960 arpstat.as_rcvlocalspa++;
961 log(LOG_ERR,
962 "duplicate IP address %s sent from link address %s\n",
963 in_fmtaddr(isaddr), lla_snprintf(ar_sha(ah), ah->ar_hln));
964 itaddr = myaddr;
965 goto reply;
966 }
967 la = arplookup(m, &isaddr, in_hosteq(itaddr, myaddr), 0);
968 if (la && (rt = la->la_rt) && (sdl = SDL(rt->rt_gateway))) {
969 if (sdl->sdl_alen &&
970 bcmp((caddr_t)ar_sha(ah), LLADDR(sdl), sdl->sdl_alen)) {
971 if (rt->rt_flags & RTF_STATIC) {
972 arpstat.as_rcvoverperm++;
973 log(LOG_INFO,
974 "%s tried to overwrite permanent arp info"
975 " for %s\n",
976 lla_snprintf(ar_sha(ah), ah->ar_hln),
977 in_fmtaddr(isaddr));
978 goto out;
979 } else if (rt->rt_ifp != ifp) {
980 arpstat.as_rcvoverint++;
981 log(LOG_INFO,
982 "%s on %s tried to overwrite "
983 "arp info for %s on %s\n",
984 lla_snprintf(ar_sha(ah), ah->ar_hln),
985 ifp->if_xname, in_fmtaddr(isaddr),
986 rt->rt_ifp->if_xname);
987 goto out;
988 } else {
989 arpstat.as_rcvover++;
990 log(LOG_INFO,
991 "arp info overwritten for %s by %s\n",
992 in_fmtaddr(isaddr),
993 lla_snprintf(ar_sha(ah), ah->ar_hln));
994 }
995 }
996 /*
997 * sanity check for the address length.
998 * XXX this does not work for protocols with variable address
999 * length. -is
1000 */
1001 if (sdl->sdl_alen &&
1002 sdl->sdl_alen != ah->ar_hln) {
1003 arpstat.as_rcvlenchg++;
1004 log(LOG_WARNING,
1005 "arp from %s: new addr len %d, was %d",
1006 in_fmtaddr(isaddr), ah->ar_hln, sdl->sdl_alen);
1007 }
1008 if (ifp->if_addrlen != ah->ar_hln) {
1009 arpstat.as_rcvbadlen++;
1010 log(LOG_WARNING,
1011 "arp from %s: addr len: new %d, i/f %d (ignored)",
1012 in_fmtaddr(isaddr), ah->ar_hln,
1013 ifp->if_addrlen);
1014 goto reply;
1015 }
1016 #if NTOKEN > 0
1017 /*
1018 * XXX uses m_data and assumes the complete answer including
1019 * XXX token-ring headers is in the same buf
1020 */
1021 if (ifp->if_type == IFT_ISO88025) {
1022 struct token_header *trh;
1023
1024 trh = (struct token_header *)M_TRHSTART(m);
1025 if (trh->token_shost[0] & TOKEN_RI_PRESENT) {
1026 struct token_rif *rif;
1027 size_t riflen;
1028
1029 rif = TOKEN_RIF(trh);
1030 riflen = (ntohs(rif->tr_rcf) &
1031 TOKEN_RCF_LEN_MASK) >> 8;
1032
1033 if (riflen > 2 &&
1034 riflen < sizeof(struct token_rif) &&
1035 (riflen & 1) == 0) {
1036 rif->tr_rcf ^= htons(TOKEN_RCF_DIRECTION);
1037 rif->tr_rcf &= htons(~TOKEN_RCF_BROADCAST_MASK);
1038 bcopy(rif, TOKEN_RIF(la), riflen);
1039 }
1040 }
1041 }
1042 #endif /* NTOKEN > 0 */
1043 bcopy((caddr_t)ar_sha(ah), LLADDR(sdl),
1044 sdl->sdl_alen = ah->ar_hln);
1045 if (rt->rt_expire)
1046 rt->rt_expire = time.tv_sec + arpt_keep;
1047 rt->rt_flags &= ~RTF_REJECT;
1048 la->la_asked = 0;
1049
1050 s = splnet();
1051 mold = la->la_hold;
1052 la->la_hold = 0;
1053 splx(s);
1054
1055 if (mold) {
1056 arpstat.as_dfrsent++;
1057 (*ifp->if_output)(ifp, mold, rt_key(rt), rt);
1058 }
1059 }
1060 reply:
1061 if (op != ARPOP_REQUEST) {
1062 if (op == ARPOP_REPLY)
1063 arpstat.as_rcvreply++;
1064 out:
1065 m_freem(m);
1066 return;
1067 }
1068 arpstat.as_rcvrequest++;
1069 if (in_hosteq(itaddr, myaddr)) {
1070 /* I am the target */
1071 if (ar_tha(ah))
1072 bcopy((caddr_t)ar_sha(ah), (caddr_t)ar_tha(ah),
1073 ah->ar_hln);
1074 bcopy(LLADDR(ifp->if_sadl), (caddr_t)ar_sha(ah), ah->ar_hln);
1075 } else {
1076 la = arplookup(m, &itaddr, 0, SIN_PROXY);
1077 if (la == 0)
1078 goto out;
1079 rt = la->la_rt;
1080 if (ar_tha(ah))
1081 bcopy((caddr_t)ar_sha(ah), (caddr_t)ar_tha(ah),
1082 ah->ar_hln);
1083 sdl = SDL(rt->rt_gateway);
1084 bcopy(LLADDR(sdl), (caddr_t)ar_sha(ah), ah->ar_hln);
1085 }
1086
1087 bcopy((caddr_t)ar_spa(ah), (caddr_t)ar_tpa(ah), ah->ar_pln);
1088 bcopy((caddr_t)&itaddr, (caddr_t)ar_spa(ah), ah->ar_pln);
1089 ah->ar_op = htons(ARPOP_REPLY);
1090 ah->ar_pro = htons(ETHERTYPE_IP); /* let's be sure! */
1091 switch (ifp->if_type) {
1092 case IFT_IEEE1394:
1093 /*
1094 * ieee1394 arp reply is broadcast
1095 */
1096 m->m_flags &= ~M_MCAST;
1097 m->m_flags |= M_BCAST;
1098 m->m_len = sizeof(*ah) + (2 * ah->ar_pln) + ah->ar_hln;
1099 break;
1100
1101 default:
1102 m->m_flags &= ~(M_BCAST|M_MCAST); /* never reply by broadcast */
1103 m->m_len = sizeof(*ah) + (2 * ah->ar_pln) + (2 * ah->ar_hln);
1104 break;
1105 }
1106 m->m_pkthdr.len = m->m_len;
1107 sa.sa_family = AF_ARP;
1108 sa.sa_len = 2;
1109 arpstat.as_sndtotal++;
1110 arpstat.as_sndreply++;
1111 (*ifp->if_output)(ifp, m, &sa, (struct rtentry *)0);
1112 return;
1113 }
1114
1115 /*
1116 * Free an arp entry.
1117 */
1118 static void
1119 arptfree(la)
1120 struct llinfo_arp *la;
1121 {
1122 struct rtentry *rt = la->la_rt;
1123 struct sockaddr_dl *sdl;
1124
1125 ARP_LOCK_CHECK();
1126
1127 if (rt == 0)
1128 panic("arptfree");
1129 if (rt->rt_refcnt > 0 && (sdl = SDL(rt->rt_gateway)) &&
1130 sdl->sdl_family == AF_LINK) {
1131 sdl->sdl_alen = 0;
1132 la->la_asked = 0;
1133 rt->rt_flags &= ~RTF_REJECT;
1134 return;
1135 }
1136 rtrequest(RTM_DELETE, rt_key(rt), (struct sockaddr *)0, rt_mask(rt),
1137 0, (struct rtentry **)0);
1138 }
1139
1140 /*
1141 * Lookup or enter a new address in arptab.
1142 */
1143 static struct llinfo_arp *
1144 arplookup(m, addr, create, proxy)
1145 struct mbuf *m;
1146 struct in_addr *addr;
1147 int create, proxy;
1148 {
1149 struct arphdr *ah;
1150 struct ifnet *ifp = m->m_pkthdr.rcvif;
1151 struct rtentry *rt;
1152 static struct sockaddr_inarp sin;
1153 const char *why = 0;
1154
1155 ah = mtod(m, struct arphdr *);
1156 sin.sin_len = sizeof(sin);
1157 sin.sin_family = AF_INET;
1158 sin.sin_addr = *addr;
1159 sin.sin_other = proxy ? SIN_PROXY : 0;
1160 rt = rtalloc1(sintosa(&sin), create);
1161 if (rt == 0)
1162 return (0);
1163 rt->rt_refcnt--;
1164
1165 if (rt->rt_flags & RTF_GATEWAY)
1166 why = "host is not on local network";
1167 else if ((rt->rt_flags & RTF_LLINFO) == 0) {
1168 arpstat.as_allocfail++;
1169 why = "could not allocate llinfo";
1170 } else if (rt->rt_gateway->sa_family != AF_LINK)
1171 why = "gateway route is not ours";
1172 else
1173 return ((struct llinfo_arp *)rt->rt_llinfo);
1174
1175 if (create)
1176 log(LOG_DEBUG, "arplookup: unable to enter address"
1177 " for %s@%s on %s (%s)\n",
1178 in_fmtaddr(*addr), lla_snprintf(ar_sha(ah), ah->ar_hln),
1179 (ifp) ? ifp->if_xname : 0, why);
1180 return (0);
1181 }
1182
1183 int
1184 arpioctl(cmd, data)
1185 u_long cmd;
1186 caddr_t data;
1187 {
1188
1189 return (EOPNOTSUPP);
1190 }
1191
1192 void
1193 arp_ifinit(ifp, ifa)
1194 struct ifnet *ifp;
1195 struct ifaddr *ifa;
1196 {
1197 struct in_addr *ip;
1198
1199 /*
1200 * Warn the user if another station has this IP address,
1201 * but only if the interface IP address is not zero.
1202 */
1203 ip = &IA_SIN(ifa)->sin_addr;
1204 if (!in_nullhost(*ip))
1205 arprequest(ifp, ip, ip, LLADDR(ifp->if_sadl));
1206
1207 ifa->ifa_rtrequest = arp_rtrequest;
1208 ifa->ifa_flags |= RTF_CLONING;
1209 }
1210
1211 /*
1212 * Called from 10 Mb/s Ethernet interrupt handlers
1213 * when ether packet type ETHERTYPE_REVARP
1214 * is received. Common length and type checks are done here,
1215 * then the protocol-specific routine is called.
1216 */
1217 void
1218 revarpinput(m)
1219 struct mbuf *m;
1220 {
1221 struct arphdr *ar;
1222
1223 if (m->m_len < sizeof(struct arphdr))
1224 goto out;
1225 ar = mtod(m, struct arphdr *);
1226 #if 0 /* XXX I don't think we need this... and it will prevent other LL */
1227 if (ntohs(ar->ar_hrd) != ARPHRD_ETHER)
1228 goto out;
1229 #endif
1230 if (m->m_len < sizeof(struct arphdr) + 2 * (ar->ar_hln + ar->ar_pln))
1231 goto out;
1232 switch (ntohs(ar->ar_pro)) {
1233 case ETHERTYPE_IP:
1234 case ETHERTYPE_IPTRAILERS:
1235 in_revarpinput(m);
1236 return;
1237
1238 default:
1239 break;
1240 }
1241 out:
1242 m_freem(m);
1243 }
1244
1245 /*
1246 * RARP for Internet protocols on 10 Mb/s Ethernet.
1247 * Algorithm is that given in RFC 903.
1248 * We are only using for bootstrap purposes to get an ip address for one of
1249 * our interfaces. Thus we support no user-interface.
1250 *
1251 * Since the contents of the RARP reply are specific to the interface that
1252 * sent the request, this code must ensure that they are properly associated.
1253 *
1254 * Note: also supports ARP via RARP packets, per the RFC.
1255 */
1256 void
1257 in_revarpinput(m)
1258 struct mbuf *m;
1259 {
1260 struct ifnet *ifp;
1261 struct arphdr *ah;
1262 int op;
1263
1264 ah = mtod(m, struct arphdr *);
1265 op = ntohs(ah->ar_op);
1266
1267 switch (m->m_pkthdr.rcvif->if_type) {
1268 case IFT_IEEE1394:
1269 /* ARP without target hardware address is not supported */
1270 goto out;
1271 default:
1272 break;
1273 }
1274
1275 switch (op) {
1276 case ARPOP_REQUEST:
1277 case ARPOP_REPLY: /* per RFC */
1278 in_arpinput(m);
1279 return;
1280 case ARPOP_REVREPLY:
1281 break;
1282 case ARPOP_REVREQUEST: /* handled by rarpd(8) */
1283 default:
1284 goto out;
1285 }
1286 if (!revarp_in_progress)
1287 goto out;
1288 ifp = m->m_pkthdr.rcvif;
1289 if (ifp != myip_ifp) /* !same interface */
1290 goto out;
1291 if (myip_initialized)
1292 goto wake;
1293 if (bcmp(ar_tha(ah), LLADDR(ifp->if_sadl), ifp->if_sadl->sdl_alen))
1294 goto out;
1295 bcopy((caddr_t)ar_spa(ah), (caddr_t)&srv_ip, sizeof(srv_ip));
1296 bcopy((caddr_t)ar_tpa(ah), (caddr_t)&myip, sizeof(myip));
1297 myip_initialized = 1;
1298 wake: /* Do wakeup every time in case it was missed. */
1299 wakeup((caddr_t)&myip);
1300
1301 out:
1302 m_freem(m);
1303 }
1304
1305 /*
1306 * Send a RARP request for the ip address of the specified interface.
1307 * The request should be RFC 903-compliant.
1308 */
1309 void
1310 revarprequest(ifp)
1311 struct ifnet *ifp;
1312 {
1313 struct sockaddr sa;
1314 struct mbuf *m;
1315 struct arphdr *ah;
1316
1317 if ((m = m_gethdr(M_DONTWAIT, MT_DATA)) == NULL)
1318 return;
1319 MCLAIM(m, &arpdomain.dom_mowner);
1320 m->m_len = sizeof(*ah) + 2*sizeof(struct in_addr) +
1321 2*ifp->if_addrlen;
1322 m->m_pkthdr.len = m->m_len;
1323 MH_ALIGN(m, m->m_len);
1324 ah = mtod(m, struct arphdr *);
1325 bzero((caddr_t)ah, m->m_len);
1326 ah->ar_pro = htons(ETHERTYPE_IP);
1327 ah->ar_hln = ifp->if_addrlen; /* hardware address length */
1328 ah->ar_pln = sizeof(struct in_addr); /* protocol address length */
1329 ah->ar_op = htons(ARPOP_REVREQUEST);
1330
1331 bcopy(LLADDR(ifp->if_sadl), (caddr_t)ar_sha(ah), ah->ar_hln);
1332 bcopy(LLADDR(ifp->if_sadl), (caddr_t)ar_tha(ah), ah->ar_hln);
1333
1334 sa.sa_family = AF_ARP;
1335 sa.sa_len = 2;
1336 m->m_flags |= M_BCAST;
1337 (*ifp->if_output)(ifp, m, &sa, (struct rtentry *)0);
1338
1339 }
1340
1341 /*
1342 * RARP for the ip address of the specified interface, but also
1343 * save the ip address of the server that sent the answer.
1344 * Timeout if no response is received.
1345 */
1346 int
1347 revarpwhoarewe(ifp, serv_in, clnt_in)
1348 struct ifnet *ifp;
1349 struct in_addr *serv_in;
1350 struct in_addr *clnt_in;
1351 {
1352 int result, count = 20;
1353
1354 myip_initialized = 0;
1355 myip_ifp = ifp;
1356
1357 revarp_in_progress = 1;
1358 while (count--) {
1359 revarprequest(ifp);
1360 result = tsleep((caddr_t)&myip, PSOCK, "revarp", hz/2);
1361 if (result != EWOULDBLOCK)
1362 break;
1363 }
1364 revarp_in_progress = 0;
1365
1366 if (!myip_initialized)
1367 return ENETUNREACH;
1368
1369 bcopy((caddr_t)&srv_ip, serv_in, sizeof(*serv_in));
1370 bcopy((caddr_t)&myip, clnt_in, sizeof(*clnt_in));
1371 return 0;
1372 }
1373
1374
1375
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 */
1494