1 /* 2 * Copyright (c) 2004, 2005 The DragonFly Project. All rights reserved. 3 * 4 * This code is derived from software contributed to The DragonFly Project 5 * by Jeffrey M. Hsu. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. Neither the name of The DragonFly Project nor the names of its 16 * contributors may be used to endorse or promote products derived 17 * from this software without specific, prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 21 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 22 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE 23 * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 24 * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING, 25 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 26 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED 27 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 28 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT 29 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30 * SUCH DAMAGE. 31 */ 32 33 /* 34 * Copyright (c) 1982, 1986, 1988, 1993 35 * The Regents of the University of California. All rights reserved. 36 * 37 * Redistribution and use in source and binary forms, with or without 38 * modification, are permitted provided that the following conditions 39 * are met: 40 * 1. Redistributions of source code must retain the above copyright 41 * notice, this list of conditions and the following disclaimer. 42 * 2. Redistributions in binary form must reproduce the above copyright 43 * notice, this list of conditions and the following disclaimer in the 44 * documentation and/or other materials provided with the distribution. 45 * 3. All advertising materials mentioning features or use of this software 46 * must display the following acknowledgement: 47 * This product includes software developed by the University of 48 * California, Berkeley and its contributors. 49 * 4. Neither the name of the University nor the names of its contributors 50 * may be used to endorse or promote products derived from this software 51 * without specific prior written permission. 52 * 53 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 54 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 55 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 56 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 57 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 58 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 59 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 60 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 61 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 62 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 63 * SUCH DAMAGE. 64 * 65 * @(#)if_ether.c 8.1 (Berkeley) 6/10/93 66 * $FreeBSD: src/sys/netinet/if_ether.c,v 1.64.2.23 2003/04/11 07:23:15 fjoe Exp $ 67 */ 68 69 /* 70 * Ethernet address resolution protocol. 71 * TODO: 72 * add "inuse/lock" bit (or ref. count) along with valid bit 73 */ 74 75 #include "opt_inet.h" 76 #include "opt_carp.h" 77 78 #include <sys/param.h> 79 #include <sys/kernel.h> 80 #include <sys/queue.h> 81 #include <sys/sysctl.h> 82 #include <sys/systm.h> 83 #include <sys/mbuf.h> 84 #include <sys/malloc.h> 85 #include <sys/socket.h> 86 #include <sys/syslog.h> 87 #include <sys/lock.h> 88 89 #include <net/if.h> 90 #include <net/if_dl.h> 91 #include <net/if_types.h> 92 #include <net/route.h> 93 #include <net/netisr.h> 94 #include <net/if_llc.h> 95 96 #include <netinet/in.h> 97 #include <netinet/in_var.h> 98 #include <netinet/if_ether.h> 99 100 #include <sys/thread2.h> 101 #include <sys/msgport2.h> 102 #include <net/netmsg2.h> 103 #include <sys/mplock2.h> 104 105 #ifdef CARP 106 #include <netinet/ip_carp.h> 107 #endif 108 109 #define SIN(s) ((struct sockaddr_in *)s) 110 #define SDL(s) ((struct sockaddr_dl *)s) 111 112 SYSCTL_DECL(_net_link_ether); 113 SYSCTL_NODE(_net_link_ether, PF_INET, inet, CTLFLAG_RW, 0, ""); 114 115 /* timer values */ 116 static int arpt_prune = (5*60*1); /* walk list every 5 minutes */ 117 static int arpt_keep = (20*60); /* once resolved, good for 20 more minutes */ 118 static int arpt_down = 20; /* once declared down, don't send for 20 sec */ 119 120 SYSCTL_INT(_net_link_ether_inet, OID_AUTO, prune_intvl, CTLFLAG_RW, 121 &arpt_prune, 0, ""); 122 SYSCTL_INT(_net_link_ether_inet, OID_AUTO, max_age, CTLFLAG_RW, 123 &arpt_keep, 0, ""); 124 SYSCTL_INT(_net_link_ether_inet, OID_AUTO, host_down_time, CTLFLAG_RW, 125 &arpt_down, 0, ""); 126 127 #define rt_expire rt_rmx.rmx_expire 128 129 struct llinfo_arp { 130 LIST_ENTRY(llinfo_arp) la_le; 131 struct rtentry *la_rt; 132 struct mbuf *la_hold; /* last packet until resolved/timeout */ 133 struct lwkt_port *la_msgport; /* last packet's msgport */ 134 u_short la_preempt; /* countdown for pre-expiry arps */ 135 u_short la_asked; /* #times we QUERIED following expiration */ 136 }; 137 138 static LIST_HEAD(, llinfo_arp) llinfo_arp_list[MAXCPU]; 139 140 static int arp_maxtries = 5; 141 static int useloopback = 1; /* use loopback interface for local traffic */ 142 static int arp_proxyall = 0; 143 static int arp_refresh = 60; /* refresh arp cache ~60 (not impl yet) */ 144 static int arp_restricted_match = 0; 145 146 SYSCTL_INT(_net_link_ether_inet, OID_AUTO, maxtries, CTLFLAG_RW, 147 &arp_maxtries, 0, "ARP resolution attempts before returning error"); 148 SYSCTL_INT(_net_link_ether_inet, OID_AUTO, useloopback, CTLFLAG_RW, 149 &useloopback, 0, "Use the loopback interface for local traffic"); 150 SYSCTL_INT(_net_link_ether_inet, OID_AUTO, proxyall, CTLFLAG_RW, 151 &arp_proxyall, 0, "Enable proxy ARP for all suitable requests"); 152 SYSCTL_INT(_net_link_ether_inet, OID_AUTO, restricted_match, CTLFLAG_RW, 153 &arp_restricted_match, 0, "Only match against the sender"); 154 SYSCTL_INT(_net_link_ether_inet, OID_AUTO, refresh, CTLFLAG_RW, 155 &arp_refresh, 0, "Preemptively refresh the ARP"); 156 157 static void arp_rtrequest(int, struct rtentry *, struct rt_addrinfo *); 158 static void arprequest(struct ifnet *, const struct in_addr *, 159 const struct in_addr *, const u_char *); 160 static void arprequest_async(struct ifnet *, const struct in_addr *, 161 const struct in_addr *, const u_char *); 162 static void arpintr(netmsg_t msg); 163 static void arptfree(struct llinfo_arp *); 164 static void arptimer(void *); 165 static struct llinfo_arp * 166 arplookup(in_addr_t, boolean_t, boolean_t, boolean_t); 167 #ifdef INET 168 static void in_arpinput(struct mbuf *); 169 #endif 170 171 static struct callout arptimer_ch[MAXCPU]; 172 173 /* 174 * Timeout routine. Age arp_tab entries periodically. 175 */ 176 /* ARGSUSED */ 177 static void 178 arptimer(void *ignored_arg) 179 { 180 struct llinfo_arp *la, *nla; 181 182 crit_enter(); 183 LIST_FOREACH_MUTABLE(la, &llinfo_arp_list[mycpuid], la_le, nla) { 184 if (la->la_rt->rt_expire && la->la_rt->rt_expire <= time_second) 185 arptfree(la); 186 } 187 callout_reset(&arptimer_ch[mycpuid], arpt_prune * hz, arptimer, NULL); 188 crit_exit(); 189 } 190 191 /* 192 * Parallel to llc_rtrequest. 193 * 194 * Called after a route is successfully added to the tree to fix-up the 195 * route and initiate arp operations if required. 196 */ 197 static void 198 arp_rtrequest(int req, struct rtentry *rt, struct rt_addrinfo *info) 199 { 200 struct sockaddr *gate = rt->rt_gateway; 201 struct llinfo_arp *la = rt->rt_llinfo; 202 203 struct sockaddr_dl null_sdl = { sizeof null_sdl, AF_LINK }; 204 static boolean_t arpinit_done[MAXCPU]; 205 206 if (!arpinit_done[mycpuid]) { 207 arpinit_done[mycpuid] = TRUE; 208 callout_init(&arptimer_ch[mycpuid]); 209 callout_reset(&arptimer_ch[mycpuid], hz, arptimer, NULL); 210 } 211 if (rt->rt_flags & RTF_GATEWAY) 212 return; 213 214 switch (req) { 215 case RTM_ADD: 216 /* 217 * XXX: If this is a manually added route to interface 218 * such as older version of routed or gated might provide, 219 * restore cloning bit. 220 */ 221 if (!(rt->rt_flags & RTF_HOST) && 222 SIN(rt_mask(rt))->sin_addr.s_addr != 0xffffffff) 223 rt->rt_flags |= RTF_CLONING; 224 if (rt->rt_flags & RTF_CLONING) { 225 /* 226 * Case 1: This route should come from a route to iface. 227 */ 228 rt_setgate(rt, rt_key(rt), 229 (struct sockaddr *)&null_sdl, 230 RTL_DONTREPORT); 231 gate = rt->rt_gateway; 232 SDL(gate)->sdl_type = rt->rt_ifp->if_type; 233 SDL(gate)->sdl_index = rt->rt_ifp->if_index; 234 rt->rt_expire = time_second; 235 break; 236 } 237 /* Announce a new entry if requested. */ 238 if (rt->rt_flags & RTF_ANNOUNCE) { 239 arprequest_async(rt->rt_ifp, 240 &SIN(rt_key(rt))->sin_addr, 241 &SIN(rt_key(rt))->sin_addr, 242 LLADDR(SDL(gate))); 243 } 244 /*FALLTHROUGH*/ 245 case RTM_RESOLVE: 246 if (gate->sa_family != AF_LINK || 247 gate->sa_len < sizeof(struct sockaddr_dl)) { 248 log(LOG_DEBUG, "arp_rtrequest: bad gateway value\n"); 249 break; 250 } 251 SDL(gate)->sdl_type = rt->rt_ifp->if_type; 252 SDL(gate)->sdl_index = rt->rt_ifp->if_index; 253 if (la != NULL) 254 break; /* This happens on a route change */ 255 /* 256 * Case 2: This route may come from cloning, or a manual route 257 * add with a LL address. 258 */ 259 R_Malloc(la, struct llinfo_arp *, sizeof *la); 260 rt->rt_llinfo = la; 261 if (la == NULL) { 262 log(LOG_DEBUG, "arp_rtrequest: malloc failed\n"); 263 break; 264 } 265 bzero(la, sizeof *la); 266 la->la_rt = rt; 267 rt->rt_flags |= RTF_LLINFO; 268 LIST_INSERT_HEAD(&llinfo_arp_list[mycpuid], la, la_le); 269 270 #ifdef INET 271 /* 272 * This keeps the multicast addresses from showing up 273 * in `arp -a' listings as unresolved. It's not actually 274 * functional. Then the same for broadcast. 275 */ 276 if (IN_MULTICAST(ntohl(SIN(rt_key(rt))->sin_addr.s_addr))) { 277 ETHER_MAP_IP_MULTICAST(&SIN(rt_key(rt))->sin_addr, 278 LLADDR(SDL(gate))); 279 SDL(gate)->sdl_alen = 6; 280 rt->rt_expire = 0; 281 } 282 if (in_broadcast(SIN(rt_key(rt))->sin_addr, rt->rt_ifp)) { 283 memcpy(LLADDR(SDL(gate)), rt->rt_ifp->if_broadcastaddr, 284 rt->rt_ifp->if_addrlen); 285 SDL(gate)->sdl_alen = rt->rt_ifp->if_addrlen; 286 rt->rt_expire = 0; 287 } 288 #endif 289 290 /* 291 * This fixes up the routing interface for local addresses. 292 * The route is adjusted to point at lo0 and the expiration 293 * timer is disabled. 294 * 295 * NOTE: This prevents locally targetted traffic from going 296 * out the hardware interface, which is inefficient 297 * and might not work if the hardware cannot listen 298 * to its own transmitted packets. Setting 299 * net.link.ether.inet.useloopback to 0 will force 300 * packets for local addresses out the hardware (and 301 * it is expected to receive its own packet). 302 * 303 * XXX We should just be able to test RTF_LOCAL here instead 304 * of having to compare IPs. 305 */ 306 if (SIN(rt_key(rt))->sin_addr.s_addr == 307 (IA_SIN(rt->rt_ifa))->sin_addr.s_addr) { 308 rt->rt_expire = 0; 309 bcopy(IF_LLADDR(rt->rt_ifp), LLADDR(SDL(gate)), 310 SDL(gate)->sdl_alen = rt->rt_ifp->if_addrlen); 311 if (useloopback) 312 rt->rt_ifp = loif; 313 } 314 break; 315 316 case RTM_DELETE: 317 if (la == NULL) 318 break; 319 LIST_REMOVE(la, la_le); 320 rt->rt_llinfo = NULL; 321 rt->rt_flags &= ~RTF_LLINFO; 322 if (la->la_hold != NULL) 323 m_freem(la->la_hold); 324 Free(la); 325 break; 326 } 327 } 328 329 static struct mbuf * 330 arpreq_alloc(struct ifnet *ifp, const struct in_addr *sip, 331 const struct in_addr *tip, const u_char *enaddr) 332 { 333 struct mbuf *m; 334 struct arphdr *ah; 335 u_short ar_hrd; 336 337 if ((m = m_gethdr(MB_DONTWAIT, MT_DATA)) == NULL) 338 return NULL; 339 m->m_pkthdr.rcvif = NULL; 340 341 switch (ifp->if_type) { 342 case IFT_ETHER: 343 /* 344 * This may not be correct for types not explicitly 345 * listed, but this is our best guess 346 */ 347 default: 348 ar_hrd = htons(ARPHRD_ETHER); 349 350 m->m_len = arphdr_len2(ifp->if_addrlen, sizeof(struct in_addr)); 351 m->m_pkthdr.len = m->m_len; 352 MH_ALIGN(m, m->m_len); 353 354 ah = mtod(m, struct arphdr *); 355 break; 356 } 357 358 ah->ar_hrd = ar_hrd; 359 ah->ar_pro = htons(ETHERTYPE_IP); 360 ah->ar_hln = ifp->if_addrlen; /* hardware address length */ 361 ah->ar_pln = sizeof(struct in_addr); /* protocol address length */ 362 ah->ar_op = htons(ARPOP_REQUEST); 363 memcpy(ar_sha(ah), enaddr, ah->ar_hln); 364 memset(ar_tha(ah), 0, ah->ar_hln); 365 memcpy(ar_spa(ah), sip, ah->ar_pln); 366 memcpy(ar_tpa(ah), tip, ah->ar_pln); 367 368 return m; 369 } 370 371 static void 372 arpreq_send(struct ifnet *ifp, struct mbuf *m) 373 { 374 struct sockaddr sa; 375 struct ether_header *eh; 376 377 switch (ifp->if_type) { 378 case IFT_ETHER: 379 /* 380 * This may not be correct for types not explicitly 381 * listed, but this is our best guess 382 */ 383 default: 384 eh = (struct ether_header *)sa.sa_data; 385 /* if_output() will not swap */ 386 eh->ether_type = htons(ETHERTYPE_ARP); 387 memcpy(eh->ether_dhost, ifp->if_broadcastaddr, ifp->if_addrlen); 388 break; 389 } 390 391 sa.sa_family = AF_UNSPEC; 392 sa.sa_len = sizeof(sa); 393 ifp->if_output(ifp, m, &sa, NULL); 394 } 395 396 static void 397 arpreq_send_handler(netmsg_t msg) 398 { 399 struct mbuf *m = msg->packet.nm_packet; 400 struct ifnet *ifp = msg->lmsg.u.ms_resultp; 401 402 arpreq_send(ifp, m); 403 /* nmsg was embedded in the mbuf, do not reply! */ 404 } 405 406 /* 407 * Broadcast an ARP request. Caller specifies: 408 * - arp header source ip address 409 * - arp header target ip address 410 * - arp header source ethernet address 411 * 412 * NOTE: Caller MUST NOT hold ifp's serializer 413 */ 414 static void 415 arprequest(struct ifnet *ifp, const struct in_addr *sip, 416 const struct in_addr *tip, const u_char *enaddr) 417 { 418 struct mbuf *m; 419 420 if (enaddr == NULL) { 421 if (ifp->if_bridge) { 422 enaddr = IF_LLADDR(ether_bridge_interface(ifp)); 423 } else { 424 enaddr = IF_LLADDR(ifp); 425 } 426 } 427 428 m = arpreq_alloc(ifp, sip, tip, enaddr); 429 if (m == NULL) 430 return; 431 arpreq_send(ifp, m); 432 } 433 434 /* 435 * Same as arprequest(), except: 436 * - Caller is allowed to hold ifp's serializer 437 * - Network output is done in protocol thead 438 */ 439 static void 440 arprequest_async(struct ifnet *ifp, const struct in_addr *sip, 441 const struct in_addr *tip, const u_char *enaddr) 442 { 443 struct mbuf *m; 444 struct netmsg_packet *pmsg; 445 446 if (enaddr == NULL) { 447 if (ifp->if_bridge) { 448 enaddr = IF_LLADDR(ether_bridge_interface(ifp)); 449 } else { 450 enaddr = IF_LLADDR(ifp); 451 } 452 } 453 m = arpreq_alloc(ifp, sip, tip, enaddr); 454 if (m == NULL) 455 return; 456 457 pmsg = &m->m_hdr.mh_netmsg; 458 netmsg_init(&pmsg->base, NULL, &netisr_apanic_rport, 459 0, arpreq_send_handler); 460 pmsg->nm_packet = m; 461 pmsg->base.lmsg.u.ms_resultp = ifp; 462 463 lwkt_sendmsg(netisr_portfn(mycpuid), &pmsg->base.lmsg); 464 } 465 466 /* 467 * Resolve an IP address into an ethernet address. If success, 468 * desten is filled in. If there is no entry in arptab, 469 * set one up and broadcast a request for the IP address. 470 * Hold onto this mbuf and resend it once the address 471 * is finally resolved. A return value of 1 indicates 472 * that desten has been filled in and the packet should be sent 473 * normally; a 0 return indicates that the packet has been 474 * taken over here, either now or for later transmission. 475 */ 476 int 477 arpresolve(struct ifnet *ifp, struct rtentry *rt0, struct mbuf *m, 478 struct sockaddr *dst, u_char *desten) 479 { 480 struct rtentry *rt; 481 struct llinfo_arp *la = NULL; 482 struct sockaddr_dl *sdl; 483 484 if (m->m_flags & M_BCAST) { /* broadcast */ 485 memcpy(desten, ifp->if_broadcastaddr, ifp->if_addrlen); 486 return (1); 487 } 488 if (m->m_flags & M_MCAST) {/* multicast */ 489 ETHER_MAP_IP_MULTICAST(&SIN(dst)->sin_addr, desten); 490 return (1); 491 } 492 if (rt0 != NULL) { 493 if (rt_llroute(dst, rt0, &rt) != 0) { 494 m_freem(m); 495 return 0; 496 } 497 la = rt->rt_llinfo; 498 } 499 if (la == NULL) { 500 la = arplookup(SIN(dst)->sin_addr.s_addr, 501 TRUE, RTL_REPORTMSG, FALSE); 502 if (la != NULL) 503 rt = la->la_rt; 504 } 505 if (la == NULL || rt == NULL) { 506 log(LOG_DEBUG, "arpresolve: can't allocate llinfo for %s%s%s\n", 507 inet_ntoa(SIN(dst)->sin_addr), la ? "la" : " ", 508 rt ? "rt" : ""); 509 m_freem(m); 510 return (0); 511 } 512 sdl = SDL(rt->rt_gateway); 513 /* 514 * Check the address family and length is valid, the address 515 * is resolved; otherwise, try to resolve. 516 */ 517 if ((rt->rt_expire == 0 || rt->rt_expire > time_second) && 518 sdl->sdl_family == AF_LINK && sdl->sdl_alen != 0) { 519 /* 520 * If entry has an expiry time and it is approaching, 521 * see if we need to send an ARP request within this 522 * arpt_down interval. 523 */ 524 if ((rt->rt_expire != 0) && 525 (time_second + la->la_preempt > rt->rt_expire)) { 526 arprequest(ifp, 527 &SIN(rt->rt_ifa->ifa_addr)->sin_addr, 528 &SIN(dst)->sin_addr, 529 NULL); 530 la->la_preempt--; 531 } 532 533 bcopy(LLADDR(sdl), desten, sdl->sdl_alen); 534 return 1; 535 } 536 /* 537 * If ARP is disabled or static on this interface, stop. 538 * XXX 539 * Probably should not allocate empty llinfo struct if we are 540 * not going to be sending out an arp request. 541 */ 542 if (ifp->if_flags & (IFF_NOARP | IFF_STATICARP)) { 543 m_freem(m); 544 return (0); 545 } 546 /* 547 * There is an arptab entry, but no ethernet address 548 * response yet. Replace the held mbuf with this 549 * latest one. 550 */ 551 if (la->la_hold != NULL) 552 m_freem(la->la_hold); 553 la->la_hold = m; 554 la->la_msgport = cur_netport(); 555 if (rt->rt_expire || ((rt->rt_flags & RTF_STATIC) && !sdl->sdl_alen)) { 556 rt->rt_flags &= ~RTF_REJECT; 557 if (la->la_asked == 0 || rt->rt_expire != time_second) { 558 rt->rt_expire = time_second; 559 if (la->la_asked++ < arp_maxtries) { 560 arprequest(ifp, 561 &SIN(rt->rt_ifa->ifa_addr)->sin_addr, 562 &SIN(dst)->sin_addr, 563 NULL); 564 } else { 565 rt->rt_flags |= RTF_REJECT; 566 rt->rt_expire += arpt_down; 567 la->la_asked = 0; 568 la->la_preempt = arp_maxtries; 569 } 570 } 571 } 572 return (0); 573 } 574 575 /* 576 * Common length and type checks are done here, 577 * then the protocol-specific routine is called. 578 */ 579 static void 580 arpintr(netmsg_t msg) 581 { 582 struct mbuf *m = msg->packet.nm_packet; 583 struct arphdr *ar; 584 u_short ar_hrd; 585 char hexstr[6]; 586 587 if (m->m_len < sizeof(struct arphdr) && 588 (m = m_pullup(m, sizeof(struct arphdr))) == NULL) { 589 log(LOG_ERR, "arp: runt packet -- m_pullup failed\n"); 590 return; 591 } 592 ar = mtod(m, struct arphdr *); 593 594 ar_hrd = ntohs(ar->ar_hrd); 595 if (ar_hrd != ARPHRD_ETHER && ar_hrd != ARPHRD_IEEE802) { 596 hexncpy((unsigned char *)&ar->ar_hrd, 2, hexstr, 5, NULL); 597 log(LOG_ERR, "arp: unknown hardware address format (0x%s)\n", 598 hexstr); 599 m_freem(m); 600 return; 601 } 602 603 if (m->m_pkthdr.len < arphdr_len(ar)) { 604 if ((m = m_pullup(m, arphdr_len(ar))) == NULL) { 605 log(LOG_ERR, "arp: runt packet\n"); 606 return; 607 } 608 ar = mtod(m, struct arphdr *); 609 } 610 611 switch (ntohs(ar->ar_pro)) { 612 #ifdef INET 613 case ETHERTYPE_IP: 614 in_arpinput(m); 615 return; 616 #endif 617 } 618 m_freem(m); 619 /* msg was embedded in the mbuf, do not reply! */ 620 } 621 622 #ifdef INET 623 /* 624 * ARP for Internet protocols on 10 Mb/s Ethernet. 625 * Algorithm is that given in RFC 826. 626 * In addition, a sanity check is performed on the sender 627 * protocol address, to catch impersonators. 628 * We no longer handle negotiations for use of trailer protocol: 629 * Formerly, ARP replied for protocol type ETHERTYPE_TRAIL sent 630 * along with IP replies if we wanted trailers sent to us, 631 * and also sent them in response to IP replies. 632 * This allowed either end to announce the desire to receive 633 * trailer packets. 634 * We no longer reply to requests for ETHERTYPE_TRAIL protocol either, 635 * but formerly didn't normally send requests. 636 */ 637 638 static int log_arp_wrong_iface = 1; 639 static int log_arp_movements = 1; 640 static int log_arp_permanent_modify = 1; 641 642 SYSCTL_INT(_net_link_ether_inet, OID_AUTO, log_arp_wrong_iface, CTLFLAG_RW, 643 &log_arp_wrong_iface, 0, 644 "Log arp packets arriving on the wrong interface"); 645 SYSCTL_INT(_net_link_ether_inet, OID_AUTO, log_arp_movements, CTLFLAG_RW, 646 &log_arp_movements, 0, 647 "Log arp replies from MACs different than the one in the cache"); 648 SYSCTL_INT(_net_link_ether_inet, OID_AUTO, log_arp_permanent_modify, CTLFLAG_RW, 649 &log_arp_permanent_modify, 0, 650 "Log arp replies from MACs different than the one " 651 "in the permanent arp entry"); 652 653 654 static void 655 arp_hold_output(netmsg_t msg) 656 { 657 struct mbuf *m = msg->packet.nm_packet; 658 struct rtentry *rt; 659 struct ifnet *ifp; 660 661 rt = msg->lmsg.u.ms_resultp; 662 ifp = m->m_pkthdr.rcvif; 663 m->m_pkthdr.rcvif = NULL; 664 665 ifp->if_output(ifp, m, rt_key(rt), rt); 666 667 /* Drop the reference count bumped by the sender */ 668 RTFREE(rt); 669 670 /* nmsg was embedded in the mbuf, do not reply! */ 671 } 672 673 static void 674 arp_update_oncpu(struct mbuf *m, in_addr_t saddr, boolean_t create, 675 boolean_t generate_report, boolean_t dologging) 676 { 677 struct arphdr *ah = mtod(m, struct arphdr *); 678 struct ifnet *ifp = m->m_pkthdr.rcvif; 679 struct llinfo_arp *la; 680 struct sockaddr_dl *sdl; 681 struct rtentry *rt; 682 char hexstr[2][64]; 683 684 la = arplookup(saddr, create, generate_report, FALSE); 685 if (la && (rt = la->la_rt) && (sdl = SDL(rt->rt_gateway))) { 686 struct in_addr isaddr = { saddr }; 687 688 /* 689 * Normally arps coming in on the wrong interface are ignored, 690 * but if we are bridging and the two interfaces belong to 691 * the same bridge, or one is a member of the bridge which 692 * is the other, then it isn't an error. 693 */ 694 if (rt->rt_ifp != ifp) { 695 /* 696 * (1) ifp and rt_ifp both members of same bridge 697 * (2) rt_ifp member of bridge ifp 698 * (3) ifp member of bridge rt_ifp 699 * 700 * Always replace rt_ifp with the bridge ifc. 701 */ 702 struct ifnet *nifp; 703 704 if (ifp->if_bridge && 705 rt->rt_ifp->if_bridge == ifp->if_bridge) { 706 nifp = ether_bridge_interface(ifp); 707 } else if (rt->rt_ifp->if_bridge && 708 ether_bridge_interface(rt->rt_ifp) == ifp) { 709 nifp = ifp; 710 } else if (ifp->if_bridge && 711 ether_bridge_interface(ifp) == rt->rt_ifp) { 712 nifp = rt->rt_ifp; 713 } else { 714 nifp = NULL; 715 } 716 717 if ((log_arp_wrong_iface == 1 && nifp == NULL) || 718 log_arp_wrong_iface == 2) { 719 hexncpy((u_char *)ar_sha(ah), ifp->if_addrlen, 720 hexstr[0], HEX_NCPYLEN(ifp->if_addrlen), ":"); 721 log(LOG_ERR, 722 "arp: %s is on %s " 723 "but got reply from %s on %s\n", 724 inet_ntoa(isaddr), 725 rt->rt_ifp->if_xname, hexstr[0], 726 ifp->if_xname); 727 } 728 if (nifp == NULL) 729 return; 730 731 /* 732 * nifp is our man! Replace rt_ifp and adjust 733 * the sdl. 734 */ 735 ifp = rt->rt_ifp = nifp; 736 sdl->sdl_type = ifp->if_type; 737 sdl->sdl_index = ifp->if_index; 738 } 739 if (sdl->sdl_alen && 740 bcmp(ar_sha(ah), LLADDR(sdl), sdl->sdl_alen)) { 741 if (rt->rt_expire != 0) { 742 if (dologging && log_arp_movements) { 743 hexncpy((u_char *)LLADDR(sdl), ifp->if_addrlen, 744 hexstr[0], HEX_NCPYLEN(ifp->if_addrlen), ":"); 745 hexncpy((u_char *)ar_sha(ah), ifp->if_addrlen, 746 hexstr[1], HEX_NCPYLEN(ifp->if_addrlen), ":"); 747 log(LOG_INFO, 748 "arp: %s moved from %s to %s on %s\n", 749 inet_ntoa(isaddr), hexstr[0], hexstr[1], 750 ifp->if_xname); 751 } 752 } else { 753 if (dologging && log_arp_permanent_modify) { 754 hexncpy((u_char *)ar_sha(ah), ifp->if_addrlen, 755 hexstr[0], HEX_NCPYLEN(ifp->if_addrlen), ":"); 756 log(LOG_ERR, 757 "arp: %s attempts to modify " 758 "permanent entry for %s on %s\n", 759 hexstr[0], inet_ntoa(isaddr), ifp->if_xname); 760 } 761 return; 762 } 763 } 764 /* 765 * sanity check for the address length. 766 * XXX this does not work for protocols with variable address 767 * length. -is 768 */ 769 if (dologging && sdl->sdl_alen && sdl->sdl_alen != ah->ar_hln) { 770 hexncpy((u_char *)ar_sha(ah), ifp->if_addrlen, 771 hexstr[0], HEX_NCPYLEN(ifp->if_addrlen), ":"); 772 log(LOG_WARNING, 773 "arp from %s: new addr len %d, was %d", 774 hexstr[0], ah->ar_hln, sdl->sdl_alen); 775 } 776 if (ifp->if_addrlen != ah->ar_hln) { 777 if (dologging) { 778 hexncpy((u_char *)ar_sha(ah), ifp->if_addrlen, 779 hexstr[0], HEX_NCPYLEN(ifp->if_addrlen), ":"); 780 log(LOG_WARNING, 781 "arp from %s: addr len: new %d, i/f %d " 782 "(ignored)", hexstr[0], 783 ah->ar_hln, ifp->if_addrlen); 784 } 785 return; 786 } 787 memcpy(LLADDR(sdl), ar_sha(ah), sdl->sdl_alen = ah->ar_hln); 788 if (rt->rt_expire != 0) { 789 rt->rt_expire = time_second + arpt_keep; 790 } 791 rt->rt_flags &= ~RTF_REJECT; 792 la->la_asked = 0; 793 la->la_preempt = arp_maxtries; 794 795 /* 796 * This particular cpu might have been holding an mbuf 797 * pending ARP resolution. If so, transmit the mbuf now. 798 */ 799 if (la->la_hold != NULL) { 800 struct mbuf *m = la->la_hold; 801 struct lwkt_port *port = la->la_msgport; 802 struct netmsg_packet *pmsg; 803 804 la->la_hold = NULL; 805 la->la_msgport = NULL; 806 807 m_adj(m, sizeof(struct ether_header)); 808 809 /* 810 * Make sure that this rtentry will not be freed 811 * before the packet is processed on the target 812 * msgport. The reference count will be dropped 813 * in the handler associated with this packet. 814 */ 815 rt->rt_refcnt++; 816 817 pmsg = &m->m_hdr.mh_netmsg; 818 netmsg_init(&pmsg->base, NULL, 819 &netisr_apanic_rport, 820 MSGF_PRIORITY, arp_hold_output); 821 pmsg->nm_packet = m; 822 823 /* Record necessary information */ 824 m->m_pkthdr.rcvif = ifp; 825 pmsg->base.lmsg.u.ms_resultp = rt; 826 827 lwkt_sendmsg(port, &pmsg->base.lmsg); 828 } 829 } 830 } 831 832 struct netmsg_arp_update { 833 struct netmsg_base base; 834 struct mbuf *m; 835 in_addr_t saddr; 836 boolean_t create; 837 }; 838 839 static void arp_update_msghandler(netmsg_t msg); 840 841 /* 842 * Called from arpintr() - this routine is run from a single cpu. 843 */ 844 static void 845 in_arpinput(struct mbuf *m) 846 { 847 struct arphdr *ah; 848 struct ifnet *ifp = m->m_pkthdr.rcvif; 849 struct ether_header *eh; 850 struct rtentry *rt; 851 struct ifaddr_container *ifac; 852 struct in_ifaddr_container *iac; 853 struct in_ifaddr *ia = NULL; 854 struct sockaddr sa; 855 struct in_addr isaddr, itaddr, myaddr; 856 struct netmsg_arp_update msg; 857 uint8_t *enaddr = NULL; 858 int op; 859 int req_len; 860 char hexstr[64]; 861 862 req_len = arphdr_len2(ifp->if_addrlen, sizeof(struct in_addr)); 863 if (m->m_len < req_len && (m = m_pullup(m, req_len)) == NULL) { 864 log(LOG_ERR, "in_arp: runt packet -- m_pullup failed\n"); 865 return; 866 } 867 868 ah = mtod(m, struct arphdr *); 869 op = ntohs(ah->ar_op); 870 memcpy(&isaddr, ar_spa(ah), sizeof isaddr); 871 memcpy(&itaddr, ar_tpa(ah), sizeof itaddr); 872 873 /* 874 * Check both target and sender IP addresses: 875 * 876 * If we receive the packet on the interface owning the address, 877 * then accept the address. 878 * 879 * For a bridge, we accept the address if the receive interface and 880 * the interface owning the address are on the same bridge, and 881 * use the bridge MAC as the is-at response. The bridge will be 882 * responsible for handling the packet. 883 * 884 * (0) Check target IP against CARP IPs 885 */ 886 #ifdef CARP 887 LIST_FOREACH(iac, INADDR_HASH(itaddr.s_addr), ia_hash) { 888 int is_match = 0, is_parent = 0; 889 890 ia = iac->ia; 891 892 /* Skip all ia's which don't match */ 893 if (itaddr.s_addr != ia->ia_addr.sin_addr.s_addr) 894 continue; 895 896 if (ia->ia_ifp->if_type != IFT_CARP) 897 continue; 898 899 if (carp_parent(ia->ia_ifp) == ifp) 900 is_parent = 1; 901 if (is_parent || ia->ia_ifp == ifp) 902 is_match = carp_iamatch(ia); 903 904 if (is_match) { 905 if (is_parent) { 906 /* 907 * The parent interface will also receive 908 * the ethernet broadcast packets, e.g. ARP 909 * REQUEST, so if we could find a CARP 910 * interface of the parent that could match 911 * the target IP address, we then drop the 912 * packets, which is delieverd to us through 913 * the parent interface. 914 */ 915 m_freem(m); 916 return; 917 } 918 goto match; 919 } 920 } 921 #endif /* CARP */ 922 923 /* 924 * (1) Check target IP against our local IPs 925 */ 926 LIST_FOREACH(iac, INADDR_HASH(itaddr.s_addr), ia_hash) { 927 ia = iac->ia; 928 929 /* Skip all ia's which don't match */ 930 if (itaddr.s_addr != ia->ia_addr.sin_addr.s_addr) 931 continue; 932 933 #ifdef CARP 934 /* CARP interfaces are checked in (0) */ 935 if (ia->ia_ifp->if_type == IFT_CARP) 936 continue; 937 #endif 938 939 if (ifp->if_bridge && ia->ia_ifp && 940 ifp->if_bridge == ia->ia_ifp->if_bridge) { 941 ifp = ether_bridge_interface(ifp); 942 goto match; 943 } 944 if (ia->ia_ifp && ia->ia_ifp->if_bridge && 945 ether_bridge_interface(ia->ia_ifp) == ifp) { 946 goto match; 947 } 948 if (ifp->if_bridge && ether_bridge_interface(ifp) == 949 ia->ia_ifp) { 950 goto match; 951 } 952 if (ia->ia_ifp == ifp) { 953 goto match; 954 } 955 } 956 957 /* 958 * (2) Check sender IP against our local IPs 959 */ 960 LIST_FOREACH(iac, INADDR_HASH(isaddr.s_addr), ia_hash) { 961 ia = iac->ia; 962 963 /* Skip all ia's which don't match */ 964 if (isaddr.s_addr != ia->ia_addr.sin_addr.s_addr) 965 continue; 966 967 if (ifp->if_bridge && ia->ia_ifp && 968 ifp->if_bridge == ia->ia_ifp->if_bridge) { 969 ifp = ether_bridge_interface(ifp); 970 goto match; 971 } 972 if (ia->ia_ifp && ia->ia_ifp->if_bridge && 973 ether_bridge_interface(ia->ia_ifp) == ifp) { 974 goto match; 975 } 976 if (ifp->if_bridge && ether_bridge_interface(ifp) == 977 ia->ia_ifp) { 978 goto match; 979 } 980 981 if (ia->ia_ifp == ifp) 982 goto match; 983 } 984 985 /* 986 * No match, use the first inet address on the receive interface 987 * as a dummy address for the rest of the function. 988 */ 989 TAILQ_FOREACH(ifac, &ifp->if_addrheads[mycpuid], ifa_link) { 990 struct ifaddr *ifa = ifac->ifa; 991 992 if (ifa->ifa_addr && ifa->ifa_addr->sa_family == AF_INET) { 993 ia = ifatoia(ifa); 994 goto match; 995 } 996 } 997 998 /* 999 * If we got here, we didn't find any suitable interface, 1000 * so drop the packet. 1001 */ 1002 m_freem(m); 1003 return; 1004 1005 match: 1006 if (!enaddr) 1007 enaddr = (uint8_t *)IF_LLADDR(ifp); 1008 myaddr = ia->ia_addr.sin_addr; 1009 if (!bcmp(ar_sha(ah), enaddr, ifp->if_addrlen)) { 1010 m_freem(m); /* it's from me, ignore it. */ 1011 return; 1012 } 1013 if (!bcmp(ar_sha(ah), ifp->if_broadcastaddr, ifp->if_addrlen)) { 1014 log(LOG_ERR, 1015 "arp: link address is broadcast for IP address %s!\n", 1016 inet_ntoa(isaddr)); 1017 m_freem(m); 1018 return; 1019 } 1020 if (isaddr.s_addr == myaddr.s_addr && myaddr.s_addr != 0) { 1021 hexncpy((u_char *)ar_sha(ah), ifp->if_addrlen, 1022 hexstr, HEX_NCPYLEN(ifp->if_addrlen), ":"); 1023 log(LOG_ERR, 1024 "arp: %s is using my IP address %s!\n", 1025 hexstr, inet_ntoa(isaddr)); 1026 itaddr = myaddr; 1027 goto reply; 1028 } 1029 if (ifp->if_flags & IFF_STATICARP) 1030 goto reply; 1031 1032 /* 1033 * When arp_restricted_match is true and the ARP response is not 1034 * specifically targetted to me, ignore it. Otherwise the entry 1035 * timeout may be updated for an old MAC. 1036 */ 1037 if (arp_restricted_match && itaddr.s_addr != myaddr.s_addr) { 1038 m_freem(m); 1039 return; 1040 } 1041 1042 netmsg_init(&msg.base, NULL, &curthread->td_msgport, 1043 0, arp_update_msghandler); 1044 msg.m = m; 1045 msg.saddr = isaddr.s_addr; 1046 msg.create = (itaddr.s_addr == myaddr.s_addr); 1047 lwkt_domsg(rtable_portfn(0), &msg.base.lmsg, 0); 1048 reply: 1049 if (op != ARPOP_REQUEST) { 1050 m_freem(m); 1051 return; 1052 } 1053 if (itaddr.s_addr == myaddr.s_addr) { 1054 /* I am the target */ 1055 memcpy(ar_tha(ah), ar_sha(ah), ah->ar_hln); 1056 memcpy(ar_sha(ah), enaddr, ah->ar_hln); 1057 } else { 1058 struct llinfo_arp *la; 1059 1060 la = arplookup(itaddr.s_addr, FALSE, RTL_DONTREPORT, SIN_PROXY); 1061 if (la == NULL) { 1062 struct sockaddr_in sin; 1063 1064 if (!arp_proxyall) { 1065 m_freem(m); 1066 return; 1067 } 1068 1069 bzero(&sin, sizeof sin); 1070 sin.sin_family = AF_INET; 1071 sin.sin_len = sizeof sin; 1072 sin.sin_addr = itaddr; 1073 1074 rt = rtpurelookup((struct sockaddr *)&sin); 1075 if (rt == NULL) { 1076 m_freem(m); 1077 return; 1078 } 1079 --rt->rt_refcnt; 1080 /* 1081 * Don't send proxies for nodes on the same interface 1082 * as this one came out of, or we'll get into a fight 1083 * over who claims what Ether address. 1084 */ 1085 if (rt->rt_ifp == ifp) { 1086 m_freem(m); 1087 return; 1088 } 1089 memcpy(ar_tha(ah), ar_sha(ah), ah->ar_hln); 1090 memcpy(ar_sha(ah), enaddr, ah->ar_hln); 1091 #ifdef DEBUG_PROXY 1092 kprintf("arp: proxying for %s\n", inet_ntoa(itaddr)); 1093 #endif 1094 } else { 1095 struct sockaddr_dl *sdl; 1096 1097 rt = la->la_rt; 1098 memcpy(ar_tha(ah), ar_sha(ah), ah->ar_hln); 1099 sdl = SDL(rt->rt_gateway); 1100 memcpy(ar_sha(ah), LLADDR(sdl), ah->ar_hln); 1101 } 1102 } 1103 1104 memcpy(ar_tpa(ah), ar_spa(ah), ah->ar_pln); 1105 memcpy(ar_spa(ah), &itaddr, ah->ar_pln); 1106 ah->ar_op = htons(ARPOP_REPLY); 1107 ah->ar_pro = htons(ETHERTYPE_IP); /* let's be sure! */ 1108 switch (ifp->if_type) { 1109 case IFT_ETHER: 1110 /* 1111 * May not be correct for types not explictly 1112 * listed, but it is our best guess. 1113 */ 1114 default: 1115 eh = (struct ether_header *)sa.sa_data; 1116 memcpy(eh->ether_dhost, ar_tha(ah), sizeof eh->ether_dhost); 1117 eh->ether_type = htons(ETHERTYPE_ARP); 1118 break; 1119 } 1120 sa.sa_family = AF_UNSPEC; 1121 sa.sa_len = sizeof sa; 1122 ifp->if_output(ifp, m, &sa, NULL); 1123 } 1124 1125 static void 1126 arp_update_msghandler(netmsg_t msg) 1127 { 1128 struct netmsg_arp_update *rmsg = (struct netmsg_arp_update *)msg; 1129 int nextcpu; 1130 1131 /* 1132 * This message handler will be called on all of the CPUs, 1133 * however, we only need to generate rtmsg on CPU0. 1134 */ 1135 arp_update_oncpu(rmsg->m, rmsg->saddr, rmsg->create, 1136 mycpuid == 0 ? RTL_REPORTMSG : RTL_DONTREPORT, 1137 mycpuid == 0); 1138 1139 nextcpu = mycpuid + 1; 1140 if (nextcpu < ncpus) 1141 lwkt_forwardmsg(rtable_portfn(nextcpu), &rmsg->base.lmsg); 1142 else 1143 lwkt_replymsg(&rmsg->base.lmsg, 0); 1144 } 1145 1146 #endif /* INET */ 1147 1148 /* 1149 * Free an arp entry. If the arp entry is actively referenced or represents 1150 * a static entry we only clear it back to an unresolved state, otherwise 1151 * we destroy the entry entirely. 1152 * 1153 * Note that static entries are created when route add ... -interface is used 1154 * to create an interface route to a (direct) destination. 1155 */ 1156 static void 1157 arptfree(struct llinfo_arp *la) 1158 { 1159 struct rtentry *rt = la->la_rt; 1160 struct sockaddr_dl *sdl; 1161 1162 if (rt == NULL) 1163 panic("arptfree"); 1164 sdl = SDL(rt->rt_gateway); 1165 if (sdl != NULL && 1166 ((rt->rt_refcnt > 0 && sdl->sdl_family == AF_LINK) || 1167 (rt->rt_flags & RTF_STATIC))) { 1168 sdl->sdl_alen = 0; 1169 la->la_preempt = la->la_asked = 0; 1170 rt->rt_flags &= ~RTF_REJECT; 1171 return; 1172 } 1173 rtrequest(RTM_DELETE, rt_key(rt), NULL, rt_mask(rt), 0, NULL); 1174 } 1175 1176 /* 1177 * Lookup or enter a new address in arptab. 1178 */ 1179 static struct llinfo_arp * 1180 arplookup(in_addr_t addr, boolean_t create, boolean_t generate_report, 1181 boolean_t proxy) 1182 { 1183 struct rtentry *rt; 1184 struct sockaddr_inarp sin = { sizeof sin, AF_INET }; 1185 const char *why = NULL; 1186 1187 sin.sin_addr.s_addr = addr; 1188 sin.sin_other = proxy ? SIN_PROXY : 0; 1189 if (create) { 1190 rt = _rtlookup((struct sockaddr *)&sin, 1191 generate_report, RTL_DOCLONE); 1192 } else { 1193 rt = rtpurelookup((struct sockaddr *)&sin); 1194 } 1195 if (rt == NULL) 1196 return (NULL); 1197 rt->rt_refcnt--; 1198 1199 if (rt->rt_flags & RTF_GATEWAY) 1200 why = "host is not on local network"; 1201 else if (!(rt->rt_flags & RTF_LLINFO)) 1202 why = "could not allocate llinfo"; 1203 else if (rt->rt_gateway->sa_family != AF_LINK) 1204 why = "gateway route is not ours"; 1205 1206 if (why) { 1207 if (create) { 1208 log(LOG_DEBUG, "arplookup %s failed: %s\n", 1209 inet_ntoa(sin.sin_addr), why); 1210 } 1211 if (rt->rt_refcnt <= 0 && (rt->rt_flags & RTF_WASCLONED)) { 1212 /* No references to this route. Purge it. */ 1213 rtrequest(RTM_DELETE, rt_key(rt), rt->rt_gateway, 1214 rt_mask(rt), rt->rt_flags, NULL); 1215 } 1216 return (NULL); 1217 } 1218 return (rt->rt_llinfo); 1219 } 1220 1221 void 1222 arp_ifinit(struct ifnet *ifp, struct ifaddr *ifa) 1223 { 1224 ifa->ifa_rtrequest = arp_rtrequest; 1225 ifa->ifa_flags |= RTF_CLONING; 1226 } 1227 1228 void 1229 arp_gratuitous(struct ifnet *ifp, struct ifaddr *ifa) 1230 { 1231 if (IA_SIN(ifa)->sin_addr.s_addr != INADDR_ANY) { 1232 arprequest_async(ifp, &IA_SIN(ifa)->sin_addr, 1233 &IA_SIN(ifa)->sin_addr, NULL); 1234 } 1235 } 1236 1237 static void 1238 arp_ifaddr(void *arg __unused, struct ifnet *ifp, 1239 enum ifaddr_event event, struct ifaddr *ifa) 1240 { 1241 if (ifa->ifa_rtrequest != arp_rtrequest) /* XXX need a generic way */ 1242 return; 1243 if (ifa->ifa_addr->sa_family != AF_INET) 1244 return; 1245 if (event == IFADDR_EVENT_DELETE) 1246 return; 1247 1248 /* 1249 * - CARP interfaces will take care of gratuitous ARP themselves. 1250 * - If we are the CARP interface's parent, don't send gratuitous 1251 * ARP to avoid unnecessary confusion. 1252 */ 1253 #ifdef CARP 1254 if (ifp->if_type != IFT_CARP && ifp->if_carp == NULL) 1255 #endif 1256 { 1257 arp_gratuitous(ifp, ifa); 1258 } 1259 } 1260 1261 static void 1262 arp_init(void) 1263 { 1264 int cpu; 1265 1266 for (cpu = 0; cpu < ncpus2; cpu++) 1267 LIST_INIT(&llinfo_arp_list[cpu]); 1268 1269 netisr_register(NETISR_ARP, arpintr, NULL); 1270 1271 EVENTHANDLER_REGISTER(ifaddr_event, arp_ifaddr, NULL, 1272 EVENTHANDLER_PRI_LAST); 1273 } 1274 1275 SYSINIT(arp, SI_SUB_PROTO_DOMAIN, SI_ORDER_ANY, arp_init, 0); 1276