if_ether.c revision 7090
1/* 2 * Copyright (c) 1982, 1986, 1988, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. All advertising materials mentioning features or use of this software 14 * must display the following acknowledgement: 15 * This product includes software developed by the University of 16 * California, Berkeley and its contributors. 17 * 4. Neither the name of the University nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 * 33 * @(#)if_ether.c 8.1 (Berkeley) 6/10/93 34 * $Id: if_ether.c,v 1.12 1995/03/16 17:32:26 wollman Exp $ 35 */ 36 37/* 38 * Ethernet address resolution protocol. 39 * TODO: 40 * add "inuse/lock" bit (or ref. count) along with valid bit 41 */ 42 43#include <sys/param.h> 44#include <sys/systm.h> 45#include <sys/malloc.h> 46#include <sys/mbuf.h> 47#include <sys/socket.h> 48#include <sys/time.h> 49#include <sys/kernel.h> 50#include <sys/errno.h> 51#include <sys/ioctl.h> 52#include <sys/syslog.h> 53 54#include <net/if.h> 55#include <net/if_dl.h> 56#include <net/route.h> 57 58#include <netinet/in.h> 59#include <netinet/in_systm.h> 60#include <netinet/in_var.h> 61#include <netinet/ip.h> 62#include <netinet/if_ether.h> 63 64#define SIN(s) ((struct sockaddr_in *)s) 65#define SDL(s) ((struct sockaddr_dl *)s) 66#define SRP(s) ((struct sockaddr_inarp *)s) 67 68/* 69 * ARP trailer negotiation. Trailer protocol is not IP specific, 70 * but ARP request/response use IP addresses. 71 */ 72#define ETHERTYPE_IPTRAILERS ETHERTYPE_TRAIL 73 74 75/* timer values */ 76int arpt_prune = (5*60*1); /* walk list every 5 minutes */ 77int arpt_keep = (20*60); /* once resolved, good for 20 more minutes */ 78int arpt_down = 20; /* once declared down, don't send for 20 secs */ 79#define rt_expire rt_rmx.rmx_expire 80 81static void arprequest __P((struct arpcom *, u_long *, u_long *, u_char *)); 82static void arptfree __P((struct llinfo_arp *)); 83static void arptimer __P((void *)); 84static struct llinfo_arp *arplookup __P((u_long, int, int)); 85static void in_arpinput __P((struct mbuf *)); 86 87struct llinfo_arp llinfo_arp = {&llinfo_arp, &llinfo_arp}; 88struct ifqueue arpintrq = {0, 0, 0, 50}; 89int arp_inuse, arp_allocated, arp_intimer; 90int arp_maxtries = 5; 91int useloopback = 1; /* use loopback interface for local traffic */ 92int arpinit_done = 0; 93 94#ifdef ARP_PROXYALL 95int arp_proxyall = 1; 96#endif 97 98/* 99 * Timeout routine. Age arp_tab entries periodically. 100 */ 101/* ARGSUSED */ 102static void 103arptimer(ignored_arg) 104 void *ignored_arg; 105{ 106 int s = splnet(); 107 register struct llinfo_arp *la = llinfo_arp.la_next; 108 109 timeout(arptimer, (caddr_t)0, arpt_prune * hz); 110 while (la != &llinfo_arp) { 111 register struct rtentry *rt = la->la_rt; 112 la = la->la_next; 113 if (rt->rt_expire && rt->rt_expire <= time.tv_sec) 114 arptfree(la->la_prev); /* timer has expired, clear */ 115 } 116 splx(s); 117} 118 119/* 120 * Parallel to llc_rtrequest. 121 */ 122static void 123arp_rtrequest(req, rt, sa) 124 int req; 125 register struct rtentry *rt; 126 struct sockaddr *sa; 127{ 128 register struct sockaddr *gate = rt->rt_gateway; 129 register struct llinfo_arp *la = (struct llinfo_arp *)rt->rt_llinfo; 130 static struct sockaddr_dl null_sdl = {sizeof(null_sdl), AF_LINK}; 131 132 if (!arpinit_done) { 133 arpinit_done = 1; 134 timeout(arptimer, (caddr_t)0, hz); 135 } 136 if (rt->rt_flags & RTF_GATEWAY) 137 return; 138 switch (req) { 139 140 case RTM_ADD: 141 /* 142 * XXX: If this is a manually added route to interface 143 * such as older version of routed or gated might provide, 144 * restore cloning bit. 145 */ 146 if ((rt->rt_flags & RTF_HOST) == 0 && 147 SIN(rt_mask(rt))->sin_addr.s_addr != 0xffffffff) 148 rt->rt_flags |= RTF_CLONING; 149#if 0 150 /* 151 * Actually, all IP gateway routes should have the cloning 152 * flag turned on. We can't do this yet because the expiration 153 * stuff isn't working yet. 154 */ 155 if (rt->rt_flags & RTF_GATEWAY) { 156 rt->rt_flags |= RTF_CLONING; 157 } 158#endif 159 if (rt->rt_flags & RTF_CLONING) { 160 /* 161 * Case 1: This route should come from a route to iface. 162 */ 163 rt_setgate(rt, rt_key(rt), 164 (struct sockaddr *)&null_sdl); 165 gate = rt->rt_gateway; 166 SDL(gate)->sdl_type = rt->rt_ifp->if_type; 167 SDL(gate)->sdl_index = rt->rt_ifp->if_index; 168 rt->rt_expire = time.tv_sec; 169 break; 170 } 171 /* Announce a new entry if requested. */ 172 if (rt->rt_flags & RTF_ANNOUNCE) 173 arprequest((struct arpcom *)rt->rt_ifp, 174 &SIN(rt_key(rt))->sin_addr.s_addr, 175 &SIN(rt_key(rt))->sin_addr.s_addr, 176 (u_char *)LLADDR(SDL(gate))); 177 /*FALLTHROUGH*/ 178 case RTM_RESOLVE: 179 if (gate->sa_family != AF_LINK || 180 gate->sa_len < sizeof(null_sdl)) { 181 log(LOG_DEBUG, "arp_rtrequest: bad gateway value\n"); 182 break; 183 } 184 SDL(gate)->sdl_type = rt->rt_ifp->if_type; 185 SDL(gate)->sdl_index = rt->rt_ifp->if_index; 186 if (la != 0) 187 break; /* This happens on a route change */ 188 /* 189 * Case 2: This route may come from cloning, or a manual route 190 * add with a LL address. 191 */ 192 R_Malloc(la, struct llinfo_arp *, sizeof(*la)); 193 rt->rt_llinfo = (caddr_t)la; 194 if (la == 0) { 195 log(LOG_DEBUG, "arp_rtrequest: malloc failed\n"); 196 break; 197 } 198 arp_inuse++, arp_allocated++; 199 Bzero(la, sizeof(*la)); 200 la->la_rt = rt; 201 rt->rt_flags |= RTF_LLINFO; 202 insque(la, &llinfo_arp); 203 if (SIN(rt_key(rt))->sin_addr.s_addr == 204 (IA_SIN(rt->rt_ifa))->sin_addr.s_addr) { 205 /* 206 * This test used to be 207 * if (loif.if_flags & IFF_UP) 208 * It allowed local traffic to be forced 209 * through the hardware by configuring the loopback down. 210 * However, it causes problems during network configuration 211 * for boards that can't receive packets they send. 212 * It is now necessary to clear "useloopback" and remove 213 * the route to force traffic out to the hardware. 214 */ 215 rt->rt_expire = 0; 216 Bcopy(((struct arpcom *)rt->rt_ifp)->ac_enaddr, 217 LLADDR(SDL(gate)), SDL(gate)->sdl_alen = 6); 218 if (useloopback) 219 rt->rt_ifp = &loif; 220 221 } 222 break; 223 224 case RTM_DELETE: 225 if (la == 0) 226 break; 227 arp_inuse--; 228 remque(la); 229 rt->rt_llinfo = 0; 230 rt->rt_flags &= ~RTF_LLINFO; 231 if (la->la_hold) 232 m_freem(la->la_hold); 233 Free((caddr_t)la); 234 } 235} 236 237/* 238 * Broadcast an ARP packet, asking who has addr on interface ac. 239 */ 240void 241arpwhohas(ac, addr) 242 register struct arpcom *ac; 243 register struct in_addr *addr; 244{ 245 arprequest(ac, &ac->ac_ipaddr.s_addr, &addr->s_addr, ac->ac_enaddr); 246} 247 248/* 249 * Broadcast an ARP request. Caller specifies: 250 * - arp header source ip address 251 * - arp header target ip address 252 * - arp header source ethernet address 253 */ 254static void 255arprequest(ac, sip, tip, enaddr) 256 register struct arpcom *ac; 257 register u_long *sip, *tip; 258 register u_char *enaddr; 259{ 260 register struct mbuf *m; 261 register struct ether_header *eh; 262 register struct ether_arp *ea; 263 struct sockaddr sa; 264 265 if ((m = m_gethdr(M_DONTWAIT, MT_DATA)) == NULL) 266 return; 267 m->m_len = sizeof(*ea); 268 m->m_pkthdr.len = sizeof(*ea); 269 MH_ALIGN(m, sizeof(*ea)); 270 ea = mtod(m, struct ether_arp *); 271 eh = (struct ether_header *)sa.sa_data; 272 bzero((caddr_t)ea, sizeof (*ea)); 273 bcopy((caddr_t)etherbroadcastaddr, (caddr_t)eh->ether_dhost, 274 sizeof(eh->ether_dhost)); 275 eh->ether_type = ETHERTYPE_ARP; /* if_output will swap */ 276 ea->arp_hrd = htons(ARPHRD_ETHER); 277 ea->arp_pro = htons(ETHERTYPE_IP); 278 ea->arp_hln = sizeof(ea->arp_sha); /* hardware address length */ 279 ea->arp_pln = sizeof(ea->arp_spa); /* protocol address length */ 280 ea->arp_op = htons(ARPOP_REQUEST); 281 bcopy((caddr_t)enaddr, (caddr_t)ea->arp_sha, sizeof(ea->arp_sha)); 282 bcopy((caddr_t)sip, (caddr_t)ea->arp_spa, sizeof(ea->arp_spa)); 283 bcopy((caddr_t)tip, (caddr_t)ea->arp_tpa, sizeof(ea->arp_tpa)); 284 sa.sa_family = AF_UNSPEC; 285 sa.sa_len = sizeof(sa); 286 (*ac->ac_if.if_output)(&ac->ac_if, m, &sa, (struct rtentry *)0); 287} 288 289/* 290 * Resolve an IP address into an ethernet address. If success, 291 * desten is filled in. If there is no entry in arptab, 292 * set one up and broadcast a request for the IP address. 293 * Hold onto this mbuf and resend it once the address 294 * is finally resolved. A return value of 1 indicates 295 * that desten has been filled in and the packet should be sent 296 * normally; a 0 return indicates that the packet has been 297 * taken over here, either now or for later transmission. 298 */ 299int 300arpresolve(ac, rt, m, dst, desten, rt0) 301 register struct arpcom *ac; 302 register struct rtentry *rt; 303 struct mbuf *m; 304 register struct sockaddr *dst; 305 register u_char *desten; 306 struct rtentry *rt0; 307{ 308 register struct llinfo_arp *la; 309 struct sockaddr_dl *sdl; 310 311 if (m->m_flags & M_BCAST) { /* broadcast */ 312 bcopy((caddr_t)etherbroadcastaddr, (caddr_t)desten, 313 sizeof(etherbroadcastaddr)); 314 return (1); 315 } 316 if (m->m_flags & M_MCAST) { /* multicast */ 317 ETHER_MAP_IP_MULTICAST(&SIN(dst)->sin_addr, desten); 318 return(1); 319 } 320 if (rt) 321 la = (struct llinfo_arp *)rt->rt_llinfo; 322 else { 323 la = arplookup(SIN(dst)->sin_addr.s_addr, 1, 0); 324 if (la) 325 rt = la->la_rt; 326 } 327 if (la == 0 || rt == 0) { 328 log(LOG_DEBUG, "arpresolve: can't allocate llinfo\n"); 329 m_freem(m); 330 return (0); 331 } 332 sdl = SDL(rt->rt_gateway); 333 /* 334 * Check the address family and length is valid, the address 335 * is resolved; otherwise, try to resolve. 336 */ 337 if ((rt->rt_expire == 0 || rt->rt_expire > time.tv_sec) && 338 sdl->sdl_family == AF_LINK && sdl->sdl_alen != 0) { 339 bcopy(LLADDR(sdl), desten, sdl->sdl_alen); 340 return 1; 341 } 342 /* 343 * There is an arptab entry, but no ethernet address 344 * response yet. Replace the held mbuf with this 345 * latest one. 346 */ 347 if (la->la_hold) 348 m_freem(la->la_hold); 349 la->la_hold = m; 350 if (rt->rt_expire) { 351 rt->rt_flags &= ~RTF_REJECT; 352 if (la->la_asked == 0 || rt->rt_expire != time.tv_sec) { 353 rt->rt_expire = time.tv_sec; 354 if (la->la_asked++ < arp_maxtries) 355 arpwhohas(ac, &(SIN(dst)->sin_addr)); 356 else { 357 rt->rt_flags |= RTF_REJECT; 358 rt->rt_expire += arpt_down; 359 la->la_asked = 0; 360 } 361 362 } 363 } 364 return (0); 365} 366 367/* 368 * Common length and type checks are done here, 369 * then the protocol-specific routine is called. 370 */ 371void 372arpintr() 373{ 374 register struct mbuf *m; 375 register struct arphdr *ar; 376 int s; 377 378 while (arpintrq.ifq_head) { 379 s = splimp(); 380 IF_DEQUEUE(&arpintrq, m); 381 splx(s); 382 if (m == 0 || (m->m_flags & M_PKTHDR) == 0) 383 panic("arpintr"); 384 if (m->m_len >= sizeof(struct arphdr) && 385 (ar = mtod(m, struct arphdr *)) && 386 ntohs(ar->ar_hrd) == ARPHRD_ETHER && 387 m->m_len >= 388 sizeof(struct arphdr) + 2 * ar->ar_hln + 2 * ar->ar_pln) 389 390 switch (ntohs(ar->ar_pro)) { 391 392 case ETHERTYPE_IP: 393 case ETHERTYPE_IPTRAILERS: 394 in_arpinput(m); 395 continue; 396 } 397 m_freem(m); 398 } 399} 400 401/* 402 * ARP for Internet protocols on 10 Mb/s Ethernet. 403 * Algorithm is that given in RFC 826. 404 * In addition, a sanity check is performed on the sender 405 * protocol address, to catch impersonators. 406 * We no longer handle negotiations for use of trailer protocol: 407 * Formerly, ARP replied for protocol type ETHERTYPE_TRAIL sent 408 * along with IP replies if we wanted trailers sent to us, 409 * and also sent them in response to IP replies. 410 * This allowed either end to announce the desire to receive 411 * trailer packets. 412 * We no longer reply to requests for ETHERTYPE_TRAIL protocol either, 413 * but formerly didn't normally send requests. 414 */ 415static void 416in_arpinput(m) 417 struct mbuf *m; 418{ 419 register struct ether_arp *ea; 420 register struct arpcom *ac = (struct arpcom *)m->m_pkthdr.rcvif; 421 struct ether_header *eh; 422 register struct llinfo_arp *la = 0; 423 register struct rtentry *rt; 424 struct in_ifaddr *ia, *maybe_ia = 0; 425 struct sockaddr_dl *sdl; 426 struct sockaddr sa; 427 struct in_addr isaddr, itaddr, myaddr; 428 int op; 429 430 ea = mtod(m, struct ether_arp *); 431 op = ntohs(ea->arp_op); 432 bcopy((caddr_t)ea->arp_spa, (caddr_t)&isaddr, sizeof (isaddr)); 433 bcopy((caddr_t)ea->arp_tpa, (caddr_t)&itaddr, sizeof (itaddr)); 434 for (ia = in_ifaddr; ia; ia = ia->ia_next) 435 if (ia->ia_ifp == &ac->ac_if) { 436 maybe_ia = ia; 437 if ((itaddr.s_addr == ia->ia_addr.sin_addr.s_addr) || 438 (isaddr.s_addr == ia->ia_addr.sin_addr.s_addr)) 439 break; 440 } 441 if (maybe_ia == 0) 442 goto out; 443 myaddr = ia ? ia->ia_addr.sin_addr : maybe_ia->ia_addr.sin_addr; 444 if (!bcmp((caddr_t)ea->arp_sha, (caddr_t)ac->ac_enaddr, 445 sizeof (ea->arp_sha))) 446 goto out; /* it's from me, ignore it. */ 447 if (!bcmp((caddr_t)ea->arp_sha, (caddr_t)etherbroadcastaddr, 448 sizeof (ea->arp_sha))) { 449 log(LOG_ERR, 450 "arp: ether address is broadcast for IP address %s!\n", 451 inet_ntoa(isaddr)); 452 goto out; 453 } 454 if (isaddr.s_addr == myaddr.s_addr) { 455 log(LOG_ERR, 456 "duplicate IP address %s! sent from ethernet address: %s\n", 457 inet_ntoa(isaddr), ether_sprintf(ea->arp_sha)); 458 itaddr = myaddr; 459 goto reply; 460 } 461 la = arplookup(isaddr.s_addr, itaddr.s_addr == myaddr.s_addr, 0); 462 if (la && (rt = la->la_rt) && (sdl = SDL(rt->rt_gateway))) { 463 if (sdl->sdl_alen && 464 bcmp((caddr_t)ea->arp_sha, LLADDR(sdl), sdl->sdl_alen)) 465 log(LOG_INFO, "arp info overwritten for %s by %s\n", 466 inet_ntoa(isaddr), ether_sprintf(ea->arp_sha)); 467 bcopy((caddr_t)ea->arp_sha, LLADDR(sdl), 468 sdl->sdl_alen = sizeof(ea->arp_sha)); 469 if (rt->rt_expire) 470 rt->rt_expire = time.tv_sec + arpt_keep; 471 rt->rt_flags &= ~RTF_REJECT; 472 la->la_asked = 0; 473 if (la->la_hold) { 474 (*ac->ac_if.if_output)(&ac->ac_if, la->la_hold, 475 rt_key(rt), rt); 476 la->la_hold = 0; 477 } 478 } 479reply: 480 if (op != ARPOP_REQUEST) { 481 out: 482 m_freem(m); 483 return; 484 } 485 if (itaddr.s_addr == myaddr.s_addr) { 486 /* I am the target */ 487 bcopy((caddr_t)ea->arp_sha, (caddr_t)ea->arp_tha, 488 sizeof(ea->arp_sha)); 489 bcopy((caddr_t)ac->ac_enaddr, (caddr_t)ea->arp_sha, 490 sizeof(ea->arp_sha)); 491 } else { 492 la = arplookup(itaddr.s_addr, 0, SIN_PROXY); 493 if (la == NULL) { 494#ifdef ARP_PROXYALL 495 struct sockaddr_in sin; 496 497 if(!arp_proxyall) goto out; 498 499 bzero(&sin, sizeof sin); 500 sin.sin_family = AF_INET; 501 sin.sin_len = sizeof sin; 502 sin.sin_addr = itaddr; 503 504 rt = rtalloc1((struct sockaddr *)&sin, 0, 0UL); 505 if( !rt ) 506 goto out; 507 /* 508 * Don't send proxies for nodes on the same interface 509 * as this one came out of, or we'll get into a fight 510 * over who claims what Ether address. 511 */ 512 if(rt->rt_ifp == &ac->ac_if) { 513 rtfree(rt); 514 goto out; 515 } 516 bcopy((caddr_t)ea->arp_sha, (caddr_t)ea->arp_tha, 517 sizeof(ea->arp_sha)); 518 bcopy(ac->ac_enaddr, (caddr_t)ea->arp_sha, 519 sizeof(ea->arp_sha)); 520 rtfree(rt); 521#ifdef DEBUG_PROXY 522 printf("arp: proxying for %s\n", 523 inet_ntoa(itaddr)); 524#endif 525#else 526 goto out; 527#endif 528 } else { 529 rt = la->la_rt; 530 bcopy((caddr_t)ea->arp_sha, (caddr_t)ea->arp_tha, 531 sizeof(ea->arp_sha)); 532 sdl = SDL(rt->rt_gateway); 533 bcopy(LLADDR(sdl), (caddr_t)ea->arp_sha, 534 sizeof(ea->arp_sha)); 535 } 536 } 537 538 bcopy((caddr_t)ea->arp_spa, (caddr_t)ea->arp_tpa, sizeof(ea->arp_spa)); 539 bcopy((caddr_t)&itaddr, (caddr_t)ea->arp_spa, sizeof(ea->arp_spa)); 540 ea->arp_op = htons(ARPOP_REPLY); 541 ea->arp_pro = htons(ETHERTYPE_IP); /* let's be sure! */ 542 eh = (struct ether_header *)sa.sa_data; 543 bcopy((caddr_t)ea->arp_tha, (caddr_t)eh->ether_dhost, 544 sizeof(eh->ether_dhost)); 545 eh->ether_type = ETHERTYPE_ARP; 546 sa.sa_family = AF_UNSPEC; 547 sa.sa_len = sizeof(sa); 548 (*ac->ac_if.if_output)(&ac->ac_if, m, &sa, (struct rtentry *)0); 549 return; 550} 551 552/* 553 * Free an arp entry. 554 */ 555static void 556arptfree(la) 557 register struct llinfo_arp *la; 558{ 559 register struct rtentry *rt = la->la_rt; 560 register struct sockaddr_dl *sdl; 561 if (rt == 0) 562 panic("arptfree"); 563 if (rt->rt_refcnt > 0 && (sdl = SDL(rt->rt_gateway)) && 564 sdl->sdl_family == AF_LINK) { 565 sdl->sdl_alen = 0; 566 la->la_asked = 0; 567 rt->rt_flags &= ~RTF_REJECT; 568 return; 569 } 570 rtrequest(RTM_DELETE, rt_key(rt), (struct sockaddr *)0, rt_mask(rt), 571 0, (struct rtentry **)0); 572} 573/* 574 * Lookup or enter a new address in arptab. 575 */ 576static struct llinfo_arp * 577arplookup(addr, create, proxy) 578 u_long addr; 579 int create, proxy; 580{ 581 register struct rtentry *rt; 582 static struct sockaddr_inarp sin = {sizeof(sin), AF_INET }; 583 const char *why = 0; 584 585 sin.sin_addr.s_addr = addr; 586 sin.sin_other = proxy ? SIN_PROXY : 0; 587 rt = rtalloc1((struct sockaddr *)&sin, create, 0UL); 588 if (rt == 0) 589 return (0); 590 rt->rt_refcnt--; 591 592 if(rt->rt_flags & RTF_GATEWAY) 593 why = "host is not on local network"; 594 else if((rt->rt_flags & RTF_LLINFO) == 0) 595 why = "could not allocate llinfo"; 596 else if(rt->rt_gateway->sa_family != AF_LINK) 597 why = "gateway route is not ours"; 598 599 if(why && create) { 600 log(LOG_DEBUG, "arplookup %s failed: %s\n", 601 inet_ntoa(sin.sin_addr), why); 602 return 0; 603 } else if(why) { 604 return 0; 605 } 606 return ((struct llinfo_arp *)rt->rt_llinfo); 607} 608 609int 610arpioctl(cmd, data) 611 int cmd; 612 caddr_t data; 613{ 614 return (EOPNOTSUPP); 615} 616 617void 618arp_ifinit(ac, ifa) 619 struct arpcom *ac; 620 struct ifaddr *ifa; 621{ 622 ac->ac_ipaddr = IA_SIN(ifa)->sin_addr; 623 arpwhohas(ac, &ac->ac_ipaddr); 624 ifa->ifa_rtrequest = arp_rtrequest; 625 ifa->ifa_flags |= RTF_CLONING; 626} 627