1 /*- 2 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project. 3 * 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. Neither the name of the project nor the names of its contributors 14 * may be used to endorse or promote products derived from this software 15 * without specific prior written permission. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE 21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * SUCH DAMAGE. 28 * 29 * $KAME: nd6_nbr.c,v 1.86 2002/01/21 02:33:04 jinmei Exp $ 30 */ 31 32 #include <sys/cdefs.h> 33 __FBSDID("$FreeBSD$"); 34 35 #include "opt_inet.h" 36 #include "opt_inet6.h" 37 #include "opt_ipsec.h" 38 #include "opt_carp.h" 39 #include "opt_mpath.h" 40 41 #include <sys/param.h> 42 #include <sys/systm.h> 43 #include <sys/malloc.h> 44 #include <sys/mbuf.h> 45 #include <sys/socket.h> 46 #include <sys/sockio.h> 47 #include <sys/time.h> 48 #include <sys/kernel.h> 49 #include <sys/errno.h> 50 #include <sys/syslog.h> 51 #include <sys/queue.h> 52 #include <sys/callout.h> 53 #include <sys/vimage.h> 54 55 #include <net/if.h> 56 #include <net/if_types.h> 57 #include <net/if_dl.h> 58 #include <net/if_var.h> 59 #include <net/route.h> 60 #ifdef RADIX_MPATH 61 #include <net/radix_mpath.h> 62 #endif 63 64 #include <netinet/in.h> 65 #include <netinet/in_var.h> 66 #include <netinet6/in6_var.h> 67 #include <netinet6/in6_ifattach.h> 68 #include <netinet/ip6.h> 69 #include <netinet6/ip6_var.h> 70 #include <netinet6/scope6_var.h> 71 #include <netinet6/nd6.h> 72 #include <netinet/icmp6.h> 73 74 #ifdef DEV_CARP 75 #include <netinet/ip_carp.h> 76 #endif 77 78 #define SDL(s) ((struct sockaddr_dl *)s) 79 80 struct dadq; 81 static struct dadq *nd6_dad_find(struct ifaddr *); 82 static void nd6_dad_starttimer(struct dadq *, int); 83 static void nd6_dad_stoptimer(struct dadq *); 84 static void nd6_dad_timer(struct ifaddr *); 85 static void nd6_dad_ns_output(struct dadq *, struct ifaddr *); 86 static void nd6_dad_ns_input(struct ifaddr *); 87 static void nd6_dad_na_input(struct ifaddr *); 88 89 static int dad_ignore_ns = 0; /* ignore NS in DAD - specwise incorrect*/ 90 static int dad_maxtry = 15; /* max # of *tries* to transmit DAD packet */ 91 92 /* 93 * Input a Neighbor Solicitation Message. 94 * 95 * Based on RFC 2461 96 * Based on RFC 2462 (duplicate address detection) 97 */ 98 void 99 nd6_ns_input(struct mbuf *m, int off, int icmp6len) 100 { 101 struct ifnet *ifp = m->m_pkthdr.rcvif; 102 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 103 struct nd_neighbor_solicit *nd_ns; 104 struct in6_addr saddr6 = ip6->ip6_src; 105 struct in6_addr daddr6 = ip6->ip6_dst; 106 struct in6_addr taddr6; 107 struct in6_addr myaddr6; 108 char *lladdr = NULL; 109 struct ifaddr *ifa = NULL; 110 int lladdrlen = 0; 111 int anycast = 0, proxy = 0, tentative = 0; 112 int tlladdr; 113 union nd_opts ndopts; 114 struct sockaddr_dl *proxydl = NULL; 115 char ip6bufs[INET6_ADDRSTRLEN], ip6bufd[INET6_ADDRSTRLEN]; 116 117 #ifndef PULLDOWN_TEST 118 IP6_EXTHDR_CHECK(m, off, icmp6len,); 119 nd_ns = (struct nd_neighbor_solicit *)((caddr_t)ip6 + off); 120 #else 121 IP6_EXTHDR_GET(nd_ns, struct nd_neighbor_solicit *, m, off, icmp6len); 122 if (nd_ns == NULL) { 123 V_icmp6stat.icp6s_tooshort++; 124 return; 125 } 126 #endif 127 ip6 = mtod(m, struct ip6_hdr *); /* adjust pointer for safety */ 128 taddr6 = nd_ns->nd_ns_target; 129 if (in6_setscope(&taddr6, ifp, NULL) != 0) 130 goto bad; 131 132 if (ip6->ip6_hlim != 255) { 133 nd6log((LOG_ERR, 134 "nd6_ns_input: invalid hlim (%d) from %s to %s on %s\n", 135 ip6->ip6_hlim, ip6_sprintf(ip6bufs, &ip6->ip6_src), 136 ip6_sprintf(ip6bufd, &ip6->ip6_dst), if_name(ifp))); 137 goto bad; 138 } 139 140 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) { 141 /* dst has to be a solicited node multicast address. */ 142 if (daddr6.s6_addr16[0] == IPV6_ADDR_INT16_MLL && 143 /* don't check ifindex portion */ 144 daddr6.s6_addr32[1] == 0 && 145 daddr6.s6_addr32[2] == IPV6_ADDR_INT32_ONE && 146 daddr6.s6_addr8[12] == 0xff) { 147 ; /* good */ 148 } else { 149 nd6log((LOG_INFO, "nd6_ns_input: bad DAD packet " 150 "(wrong ip6 dst)\n")); 151 goto bad; 152 } 153 } 154 155 if (IN6_IS_ADDR_MULTICAST(&taddr6)) { 156 nd6log((LOG_INFO, "nd6_ns_input: bad NS target (multicast)\n")); 157 goto bad; 158 } 159 160 icmp6len -= sizeof(*nd_ns); 161 nd6_option_init(nd_ns + 1, icmp6len, &ndopts); 162 if (nd6_options(&ndopts) < 0) { 163 nd6log((LOG_INFO, 164 "nd6_ns_input: invalid ND option, ignored\n")); 165 /* nd6_options have incremented stats */ 166 goto freeit; 167 } 168 169 if (ndopts.nd_opts_src_lladdr) { 170 lladdr = (char *)(ndopts.nd_opts_src_lladdr + 1); 171 lladdrlen = ndopts.nd_opts_src_lladdr->nd_opt_len << 3; 172 } 173 174 if (IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_src) && lladdr) { 175 nd6log((LOG_INFO, "nd6_ns_input: bad DAD packet " 176 "(link-layer address option)\n")); 177 goto bad; 178 } 179 180 /* 181 * Attaching target link-layer address to the NA? 182 * (RFC 2461 7.2.4) 183 * 184 * NS IP dst is unicast/anycast MUST NOT add 185 * NS IP dst is solicited-node multicast MUST add 186 * 187 * In implementation, we add target link-layer address by default. 188 * We do not add one in MUST NOT cases. 189 */ 190 if (!IN6_IS_ADDR_MULTICAST(&daddr6)) 191 tlladdr = 0; 192 else 193 tlladdr = 1; 194 195 /* 196 * Target address (taddr6) must be either: 197 * (1) Valid unicast/anycast address for my receiving interface, 198 * (2) Unicast address for which I'm offering proxy service, or 199 * (3) "tentative" address on which DAD is being performed. 200 */ 201 /* (1) and (3) check. */ 202 #ifdef DEV_CARP 203 if (ifp->if_carp) 204 ifa = carp_iamatch6(ifp->if_carp, &taddr6); 205 if (ifa == NULL) 206 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &taddr6); 207 #else 208 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &taddr6); 209 #endif 210 211 /* (2) check. */ 212 if (ifa == NULL) { 213 struct rtentry *rt; 214 struct sockaddr_in6 tsin6; 215 int need_proxy; 216 #ifdef RADIX_MPATH 217 struct route_in6 ro; 218 #endif 219 220 bzero(&tsin6, sizeof tsin6); 221 tsin6.sin6_len = sizeof(struct sockaddr_in6); 222 tsin6.sin6_family = AF_INET6; 223 tsin6.sin6_addr = taddr6; 224 225 #ifdef RADIX_MPATH 226 bzero(&ro, sizeof(ro)); 227 ro.ro_dst = tsin6; 228 rtalloc_mpath((struct route *)&ro, RTF_ANNOUNCE); 229 rt = ro.ro_rt; 230 #else 231 rt = rtalloc1((struct sockaddr *)&tsin6, 0, 0); 232 #endif 233 need_proxy = (rt && (rt->rt_flags & RTF_ANNOUNCE) != 0 && 234 rt->rt_gateway->sa_family == AF_LINK); 235 if (rt) 236 rtfree(rt); 237 if (need_proxy) { 238 /* 239 * proxy NDP for single entry 240 */ 241 ifa = (struct ifaddr *)in6ifa_ifpforlinklocal(ifp, 242 IN6_IFF_NOTREADY|IN6_IFF_ANYCAST); 243 if (ifa) { 244 proxy = 1; 245 proxydl = SDL(rt->rt_gateway); 246 } 247 } 248 } 249 if (ifa == NULL) { 250 /* 251 * We've got an NS packet, and we don't have that adddress 252 * assigned for us. We MUST silently ignore it. 253 * See RFC2461 7.2.3. 254 */ 255 goto freeit; 256 } 257 myaddr6 = *IFA_IN6(ifa); 258 anycast = ((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_ANYCAST; 259 tentative = ((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_TENTATIVE; 260 if (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_DUPLICATED) 261 goto freeit; 262 263 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) { 264 nd6log((LOG_INFO, "nd6_ns_input: lladdrlen mismatch for %s " 265 "(if %d, NS packet %d)\n", 266 ip6_sprintf(ip6bufs, &taddr6), 267 ifp->if_addrlen, lladdrlen - 2)); 268 goto bad; 269 } 270 271 if (IN6_ARE_ADDR_EQUAL(&myaddr6, &saddr6)) { 272 nd6log((LOG_INFO, "nd6_ns_input: duplicate IP6 address %s\n", 273 ip6_sprintf(ip6bufs, &saddr6))); 274 goto freeit; 275 } 276 277 /* 278 * We have neighbor solicitation packet, with target address equals to 279 * one of my tentative address. 280 * 281 * src addr how to process? 282 * --- --- 283 * multicast of course, invalid (rejected in ip6_input) 284 * unicast somebody is doing address resolution -> ignore 285 * unspec dup address detection 286 * 287 * The processing is defined in RFC 2462. 288 */ 289 if (tentative) { 290 /* 291 * If source address is unspecified address, it is for 292 * duplicate address detection. 293 * 294 * If not, the packet is for addess resolution; 295 * silently ignore it. 296 */ 297 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) 298 nd6_dad_ns_input(ifa); 299 300 goto freeit; 301 } 302 303 /* 304 * If the source address is unspecified address, entries must not 305 * be created or updated. 306 * It looks that sender is performing DAD. Output NA toward 307 * all-node multicast address, to tell the sender that I'm using 308 * the address. 309 * S bit ("solicited") must be zero. 310 */ 311 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) { 312 struct in6_addr in6_all; 313 314 in6_all = in6addr_linklocal_allnodes; 315 if (in6_setscope(&in6_all, ifp, NULL) != 0) 316 goto bad; 317 nd6_na_output(ifp, &in6_all, &taddr6, 318 ((anycast || proxy || !tlladdr) ? 0 : ND_NA_FLAG_OVERRIDE) | 319 (V_ip6_forwarding ? ND_NA_FLAG_ROUTER : 0), 320 tlladdr, (struct sockaddr *)proxydl); 321 goto freeit; 322 } 323 324 nd6_cache_lladdr(ifp, &saddr6, lladdr, lladdrlen, 325 ND_NEIGHBOR_SOLICIT, 0); 326 327 nd6_na_output(ifp, &saddr6, &taddr6, 328 ((anycast || proxy || !tlladdr) ? 0 : ND_NA_FLAG_OVERRIDE) | 329 (V_ip6_forwarding ? ND_NA_FLAG_ROUTER : 0) | ND_NA_FLAG_SOLICITED, 330 tlladdr, (struct sockaddr *)proxydl); 331 freeit: 332 m_freem(m); 333 return; 334 335 bad: 336 nd6log((LOG_ERR, "nd6_ns_input: src=%s\n", 337 ip6_sprintf(ip6bufs, &saddr6))); 338 nd6log((LOG_ERR, "nd6_ns_input: dst=%s\n", 339 ip6_sprintf(ip6bufs, &daddr6))); 340 nd6log((LOG_ERR, "nd6_ns_input: tgt=%s\n", 341 ip6_sprintf(ip6bufs, &taddr6))); 342 V_icmp6stat.icp6s_badns++; 343 m_freem(m); 344 } 345 346 /* 347 * Output a Neighbor Solicitation Message. Caller specifies: 348 * - ICMP6 header source IP6 address 349 * - ND6 header target IP6 address 350 * - ND6 header source datalink address 351 * 352 * Based on RFC 2461 353 * Based on RFC 2462 (duplicate address detection) 354 * 355 * ln - for source address determination 356 * dad - duplicate address detection 357 */ 358 void 359 nd6_ns_output(struct ifnet *ifp, const struct in6_addr *daddr6, 360 const struct in6_addr *taddr6, struct llinfo_nd6 *ln, int dad) 361 { 362 struct mbuf *m; 363 struct ip6_hdr *ip6; 364 struct nd_neighbor_solicit *nd_ns; 365 struct in6_addr *src, src_in; 366 struct ip6_moptions im6o; 367 int icmp6len; 368 int maxlen; 369 caddr_t mac; 370 struct route_in6 ro; 371 372 bzero(&ro, sizeof(ro)); 373 374 if (IN6_IS_ADDR_MULTICAST(taddr6)) 375 return; 376 377 /* estimate the size of message */ 378 maxlen = sizeof(*ip6) + sizeof(*nd_ns); 379 maxlen += (sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7; 380 if (max_linkhdr + maxlen >= MCLBYTES) { 381 #ifdef DIAGNOSTIC 382 printf("nd6_ns_output: max_linkhdr + maxlen >= MCLBYTES " 383 "(%d + %d > %d)\n", max_linkhdr, maxlen, MCLBYTES); 384 #endif 385 return; 386 } 387 388 MGETHDR(m, M_DONTWAIT, MT_DATA); 389 if (m && max_linkhdr + maxlen >= MHLEN) { 390 MCLGET(m, M_DONTWAIT); 391 if ((m->m_flags & M_EXT) == 0) { 392 m_free(m); 393 m = NULL; 394 } 395 } 396 if (m == NULL) 397 return; 398 m->m_pkthdr.rcvif = NULL; 399 400 if (daddr6 == NULL || IN6_IS_ADDR_MULTICAST(daddr6)) { 401 m->m_flags |= M_MCAST; 402 im6o.im6o_multicast_ifp = ifp; 403 im6o.im6o_multicast_hlim = 255; 404 im6o.im6o_multicast_loop = 0; 405 } 406 407 icmp6len = sizeof(*nd_ns); 408 m->m_pkthdr.len = m->m_len = sizeof(*ip6) + icmp6len; 409 m->m_data += max_linkhdr; /* or MH_ALIGN() equivalent? */ 410 411 /* fill neighbor solicitation packet */ 412 ip6 = mtod(m, struct ip6_hdr *); 413 ip6->ip6_flow = 0; 414 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 415 ip6->ip6_vfc |= IPV6_VERSION; 416 /* ip6->ip6_plen will be set later */ 417 ip6->ip6_nxt = IPPROTO_ICMPV6; 418 ip6->ip6_hlim = 255; 419 if (daddr6) 420 ip6->ip6_dst = *daddr6; 421 else { 422 ip6->ip6_dst.s6_addr16[0] = IPV6_ADDR_INT16_MLL; 423 ip6->ip6_dst.s6_addr16[1] = 0; 424 ip6->ip6_dst.s6_addr32[1] = 0; 425 ip6->ip6_dst.s6_addr32[2] = IPV6_ADDR_INT32_ONE; 426 ip6->ip6_dst.s6_addr32[3] = taddr6->s6_addr32[3]; 427 ip6->ip6_dst.s6_addr8[12] = 0xff; 428 if (in6_setscope(&ip6->ip6_dst, ifp, NULL) != 0) 429 goto bad; 430 } 431 if (!dad) { 432 /* 433 * RFC2461 7.2.2: 434 * "If the source address of the packet prompting the 435 * solicitation is the same as one of the addresses assigned 436 * to the outgoing interface, that address SHOULD be placed 437 * in the IP Source Address of the outgoing solicitation. 438 * Otherwise, any one of the addresses assigned to the 439 * interface should be used." 440 * 441 * We use the source address for the prompting packet 442 * (saddr6), if: 443 * - saddr6 is given from the caller (by giving "ln"), and 444 * - saddr6 belongs to the outgoing interface. 445 * Otherwise, we perform the source address selection as usual. 446 */ 447 struct ip6_hdr *hip6; /* hold ip6 */ 448 struct in6_addr *hsrc = NULL; 449 450 if (ln && ln->ln_hold) { 451 /* 452 * assuming every packet in ln_hold has the same IP 453 * header 454 */ 455 hip6 = mtod(ln->ln_hold, struct ip6_hdr *); 456 /* XXX pullup? */ 457 if (sizeof(*hip6) < ln->ln_hold->m_len) 458 hsrc = &hip6->ip6_src; 459 else 460 hsrc = NULL; 461 } 462 if (hsrc && in6ifa_ifpwithaddr(ifp, hsrc)) 463 src = hsrc; 464 else { 465 int error; 466 struct sockaddr_in6 dst_sa; 467 468 bzero(&dst_sa, sizeof(dst_sa)); 469 dst_sa.sin6_family = AF_INET6; 470 dst_sa.sin6_len = sizeof(dst_sa); 471 dst_sa.sin6_addr = ip6->ip6_dst; 472 473 src = in6_selectsrc(&dst_sa, NULL, 474 NULL, &ro, NULL, NULL, &error); 475 if (src == NULL) { 476 char ip6buf[INET6_ADDRSTRLEN]; 477 nd6log((LOG_DEBUG, 478 "nd6_ns_output: source can't be " 479 "determined: dst=%s, error=%d\n", 480 ip6_sprintf(ip6buf, &dst_sa.sin6_addr), 481 error)); 482 goto bad; 483 } 484 } 485 } else { 486 /* 487 * Source address for DAD packet must always be IPv6 488 * unspecified address. (0::0) 489 * We actually don't have to 0-clear the address (we did it 490 * above), but we do so here explicitly to make the intention 491 * clearer. 492 */ 493 bzero(&src_in, sizeof(src_in)); 494 src = &src_in; 495 } 496 ip6->ip6_src = *src; 497 nd_ns = (struct nd_neighbor_solicit *)(ip6 + 1); 498 nd_ns->nd_ns_type = ND_NEIGHBOR_SOLICIT; 499 nd_ns->nd_ns_code = 0; 500 nd_ns->nd_ns_reserved = 0; 501 nd_ns->nd_ns_target = *taddr6; 502 in6_clearscope(&nd_ns->nd_ns_target); /* XXX */ 503 504 /* 505 * Add source link-layer address option. 506 * 507 * spec implementation 508 * --- --- 509 * DAD packet MUST NOT do not add the option 510 * there's no link layer address: 511 * impossible do not add the option 512 * there's link layer address: 513 * Multicast NS MUST add one add the option 514 * Unicast NS SHOULD add one add the option 515 */ 516 if (!dad && (mac = nd6_ifptomac(ifp))) { 517 int optlen = sizeof(struct nd_opt_hdr) + ifp->if_addrlen; 518 struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)(nd_ns + 1); 519 /* 8 byte alignments... */ 520 optlen = (optlen + 7) & ~7; 521 522 m->m_pkthdr.len += optlen; 523 m->m_len += optlen; 524 icmp6len += optlen; 525 bzero((caddr_t)nd_opt, optlen); 526 nd_opt->nd_opt_type = ND_OPT_SOURCE_LINKADDR; 527 nd_opt->nd_opt_len = optlen >> 3; 528 bcopy(mac, (caddr_t)(nd_opt + 1), ifp->if_addrlen); 529 } 530 531 ip6->ip6_plen = htons((u_short)icmp6len); 532 nd_ns->nd_ns_cksum = 0; 533 nd_ns->nd_ns_cksum = 534 in6_cksum(m, IPPROTO_ICMPV6, sizeof(*ip6), icmp6len); 535 536 ip6_output(m, NULL, &ro, dad ? IPV6_UNSPECSRC : 0, &im6o, NULL, NULL); 537 icmp6_ifstat_inc(ifp, ifs6_out_msg); 538 icmp6_ifstat_inc(ifp, ifs6_out_neighborsolicit); 539 V_icmp6stat.icp6s_outhist[ND_NEIGHBOR_SOLICIT]++; 540 541 if (ro.ro_rt) { /* we don't cache this route. */ 542 RTFREE(ro.ro_rt); 543 } 544 return; 545 546 bad: 547 if (ro.ro_rt) { 548 RTFREE(ro.ro_rt); 549 } 550 m_freem(m); 551 return; 552 } 553 554 /* 555 * Neighbor advertisement input handling. 556 * 557 * Based on RFC 2461 558 * Based on RFC 2462 (duplicate address detection) 559 * 560 * the following items are not implemented yet: 561 * - proxy advertisement delay rule (RFC2461 7.2.8, last paragraph, SHOULD) 562 * - anycast advertisement delay rule (RFC2461 7.2.7, SHOULD) 563 */ 564 void 565 nd6_na_input(struct mbuf *m, int off, int icmp6len) 566 { 567 struct ifnet *ifp = m->m_pkthdr.rcvif; 568 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 569 struct nd_neighbor_advert *nd_na; 570 struct in6_addr daddr6 = ip6->ip6_dst; 571 struct in6_addr taddr6; 572 int flags; 573 int is_router; 574 int is_solicited; 575 int is_override; 576 char *lladdr = NULL; 577 int lladdrlen = 0; 578 struct ifaddr *ifa; 579 struct llinfo_nd6 *ln; 580 struct rtentry *rt; 581 struct sockaddr_dl *sdl; 582 union nd_opts ndopts; 583 char ip6bufs[INET6_ADDRSTRLEN], ip6bufd[INET6_ADDRSTRLEN]; 584 585 if (ip6->ip6_hlim != 255) { 586 nd6log((LOG_ERR, 587 "nd6_na_input: invalid hlim (%d) from %s to %s on %s\n", 588 ip6->ip6_hlim, ip6_sprintf(ip6bufs, &ip6->ip6_src), 589 ip6_sprintf(ip6bufd, &ip6->ip6_dst), if_name(ifp))); 590 goto bad; 591 } 592 593 #ifndef PULLDOWN_TEST 594 IP6_EXTHDR_CHECK(m, off, icmp6len,); 595 nd_na = (struct nd_neighbor_advert *)((caddr_t)ip6 + off); 596 #else 597 IP6_EXTHDR_GET(nd_na, struct nd_neighbor_advert *, m, off, icmp6len); 598 if (nd_na == NULL) { 599 V_icmp6stat.icp6s_tooshort++; 600 return; 601 } 602 #endif 603 604 flags = nd_na->nd_na_flags_reserved; 605 is_router = ((flags & ND_NA_FLAG_ROUTER) != 0); 606 is_solicited = ((flags & ND_NA_FLAG_SOLICITED) != 0); 607 is_override = ((flags & ND_NA_FLAG_OVERRIDE) != 0); 608 609 taddr6 = nd_na->nd_na_target; 610 if (in6_setscope(&taddr6, ifp, NULL)) 611 goto bad; /* XXX: impossible */ 612 613 if (IN6_IS_ADDR_MULTICAST(&taddr6)) { 614 nd6log((LOG_ERR, 615 "nd6_na_input: invalid target address %s\n", 616 ip6_sprintf(ip6bufs, &taddr6))); 617 goto bad; 618 } 619 if (IN6_IS_ADDR_MULTICAST(&daddr6)) 620 if (is_solicited) { 621 nd6log((LOG_ERR, 622 "nd6_na_input: a solicited adv is multicasted\n")); 623 goto bad; 624 } 625 626 icmp6len -= sizeof(*nd_na); 627 nd6_option_init(nd_na + 1, icmp6len, &ndopts); 628 if (nd6_options(&ndopts) < 0) { 629 nd6log((LOG_INFO, 630 "nd6_na_input: invalid ND option, ignored\n")); 631 /* nd6_options have incremented stats */ 632 goto freeit; 633 } 634 635 if (ndopts.nd_opts_tgt_lladdr) { 636 lladdr = (char *)(ndopts.nd_opts_tgt_lladdr + 1); 637 lladdrlen = ndopts.nd_opts_tgt_lladdr->nd_opt_len << 3; 638 } 639 640 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &taddr6); 641 642 /* 643 * Target address matches one of my interface address. 644 * 645 * If my address is tentative, this means that there's somebody 646 * already using the same address as mine. This indicates DAD failure. 647 * This is defined in RFC 2462. 648 * 649 * Otherwise, process as defined in RFC 2461. 650 */ 651 if (ifa 652 && (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_TENTATIVE)) { 653 nd6_dad_na_input(ifa); 654 goto freeit; 655 } 656 657 /* Just for safety, maybe unnecessary. */ 658 if (ifa) { 659 log(LOG_ERR, 660 "nd6_na_input: duplicate IP6 address %s\n", 661 ip6_sprintf(ip6bufs, &taddr6)); 662 goto freeit; 663 } 664 665 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) { 666 nd6log((LOG_INFO, "nd6_na_input: lladdrlen mismatch for %s " 667 "(if %d, NA packet %d)\n", ip6_sprintf(ip6bufs, &taddr6), 668 ifp->if_addrlen, lladdrlen - 2)); 669 goto bad; 670 } 671 672 /* 673 * If no neighbor cache entry is found, NA SHOULD silently be 674 * discarded. 675 */ 676 rt = nd6_lookup(&taddr6, 0, ifp); 677 if ((rt == NULL) || 678 ((ln = (struct llinfo_nd6 *)rt->rt_llinfo) == NULL) || 679 ((sdl = SDL(rt->rt_gateway)) == NULL)) 680 goto freeit; 681 682 if (ln->ln_state == ND6_LLINFO_INCOMPLETE) { 683 /* 684 * If the link-layer has address, and no lladdr option came, 685 * discard the packet. 686 */ 687 if (ifp->if_addrlen && lladdr == NULL) 688 goto freeit; 689 690 /* 691 * Record link-layer address, and update the state. 692 */ 693 sdl->sdl_alen = ifp->if_addrlen; 694 bcopy(lladdr, LLADDR(sdl), ifp->if_addrlen); 695 if (is_solicited) { 696 ln->ln_state = ND6_LLINFO_REACHABLE; 697 ln->ln_byhint = 0; 698 if (!ND6_LLINFO_PERMANENT(ln)) { 699 nd6_llinfo_settimer(ln, 700 (long)ND_IFINFO(rt->rt_ifp)->reachable * hz); 701 } 702 } else { 703 ln->ln_state = ND6_LLINFO_STALE; 704 nd6_llinfo_settimer(ln, (long)V_nd6_gctimer * hz); 705 } 706 if ((ln->ln_router = is_router) != 0) { 707 /* 708 * This means a router's state has changed from 709 * non-reachable to probably reachable, and might 710 * affect the status of associated prefixes.. 711 */ 712 pfxlist_onlink_check(); 713 } 714 } else { 715 int llchange; 716 717 /* 718 * Check if the link-layer address has changed or not. 719 */ 720 if (lladdr == NULL) 721 llchange = 0; 722 else { 723 if (sdl->sdl_alen) { 724 if (bcmp(lladdr, LLADDR(sdl), ifp->if_addrlen)) 725 llchange = 1; 726 else 727 llchange = 0; 728 } else 729 llchange = 1; 730 } 731 732 /* 733 * This is VERY complex. Look at it with care. 734 * 735 * override solicit lladdr llchange action 736 * (L: record lladdr) 737 * 738 * 0 0 n -- (2c) 739 * 0 0 y n (2b) L 740 * 0 0 y y (1) REACHABLE->STALE 741 * 0 1 n -- (2c) *->REACHABLE 742 * 0 1 y n (2b) L *->REACHABLE 743 * 0 1 y y (1) REACHABLE->STALE 744 * 1 0 n -- (2a) 745 * 1 0 y n (2a) L 746 * 1 0 y y (2a) L *->STALE 747 * 1 1 n -- (2a) *->REACHABLE 748 * 1 1 y n (2a) L *->REACHABLE 749 * 1 1 y y (2a) L *->REACHABLE 750 */ 751 if (!is_override && (lladdr != NULL && llchange)) { /* (1) */ 752 /* 753 * If state is REACHABLE, make it STALE. 754 * no other updates should be done. 755 */ 756 if (ln->ln_state == ND6_LLINFO_REACHABLE) { 757 ln->ln_state = ND6_LLINFO_STALE; 758 nd6_llinfo_settimer(ln, (long)V_nd6_gctimer * hz); 759 } 760 goto freeit; 761 } else if (is_override /* (2a) */ 762 || (!is_override && (lladdr != NULL && !llchange)) /* (2b) */ 763 || lladdr == NULL) { /* (2c) */ 764 /* 765 * Update link-local address, if any. 766 */ 767 if (lladdr != NULL) { 768 sdl->sdl_alen = ifp->if_addrlen; 769 bcopy(lladdr, LLADDR(sdl), ifp->if_addrlen); 770 } 771 772 /* 773 * If solicited, make the state REACHABLE. 774 * If not solicited and the link-layer address was 775 * changed, make it STALE. 776 */ 777 if (is_solicited) { 778 ln->ln_state = ND6_LLINFO_REACHABLE; 779 ln->ln_byhint = 0; 780 if (!ND6_LLINFO_PERMANENT(ln)) { 781 nd6_llinfo_settimer(ln, 782 (long)ND_IFINFO(ifp)->reachable * hz); 783 } 784 } else { 785 if (lladdr != NULL && llchange) { 786 ln->ln_state = ND6_LLINFO_STALE; 787 nd6_llinfo_settimer(ln, 788 (long)V_nd6_gctimer * hz); 789 } 790 } 791 } 792 793 if (ln->ln_router && !is_router) { 794 /* 795 * The peer dropped the router flag. 796 * Remove the sender from the Default Router List and 797 * update the Destination Cache entries. 798 */ 799 struct nd_defrouter *dr; 800 struct in6_addr *in6; 801 int s; 802 803 in6 = &((struct sockaddr_in6 *)rt_key(rt))->sin6_addr; 804 805 /* 806 * Lock to protect the default router list. 807 * XXX: this might be unnecessary, since this function 808 * is only called under the network software interrupt 809 * context. However, we keep it just for safety. 810 */ 811 s = splnet(); 812 dr = defrouter_lookup(in6, ifp); 813 if (dr) 814 defrtrlist_del(dr); 815 else if (!V_ip6_forwarding) { 816 /* 817 * Even if the neighbor is not in the default 818 * router list, the neighbor may be used 819 * as a next hop for some destinations 820 * (e.g. redirect case). So we must 821 * call rt6_flush explicitly. 822 */ 823 rt6_flush(&ip6->ip6_src, ifp); 824 } 825 splx(s); 826 } 827 ln->ln_router = is_router; 828 } 829 rt->rt_flags &= ~RTF_REJECT; 830 ln->ln_asked = 0; 831 if (ln->ln_hold) { 832 struct mbuf *m_hold, *m_hold_next; 833 834 /* 835 * reset the ln_hold in advance, to explicitly 836 * prevent a ln_hold lookup in nd6_output() 837 * (wouldn't happen, though...) 838 */ 839 for (m_hold = ln->ln_hold; 840 m_hold; m_hold = m_hold_next) { 841 m_hold_next = m_hold->m_nextpkt; 842 m_hold->m_nextpkt = NULL; 843 /* 844 * we assume ifp is not a loopback here, so just set 845 * the 2nd argument as the 1st one. 846 */ 847 nd6_output(ifp, ifp, m_hold, 848 (struct sockaddr_in6 *)rt_key(rt), rt); 849 } 850 ln->ln_hold = NULL; 851 } 852 853 freeit: 854 m_freem(m); 855 return; 856 857 bad: 858 V_icmp6stat.icp6s_badna++; 859 m_freem(m); 860 } 861 862 /* 863 * Neighbor advertisement output handling. 864 * 865 * Based on RFC 2461 866 * 867 * the following items are not implemented yet: 868 * - proxy advertisement delay rule (RFC2461 7.2.8, last paragraph, SHOULD) 869 * - anycast advertisement delay rule (RFC2461 7.2.7, SHOULD) 870 * 871 * tlladdr - 1 if include target link-layer address 872 * sdl0 - sockaddr_dl (= proxy NA) or NULL 873 */ 874 void 875 nd6_na_output(struct ifnet *ifp, const struct in6_addr *daddr6_0, 876 const struct in6_addr *taddr6, u_long flags, int tlladdr, 877 struct sockaddr *sdl0) 878 { 879 struct mbuf *m; 880 struct ip6_hdr *ip6; 881 struct nd_neighbor_advert *nd_na; 882 struct ip6_moptions im6o; 883 struct in6_addr *src, daddr6; 884 struct sockaddr_in6 dst_sa; 885 int icmp6len, maxlen, error; 886 caddr_t mac = NULL; 887 struct route_in6 ro; 888 889 bzero(&ro, sizeof(ro)); 890 891 daddr6 = *daddr6_0; /* make a local copy for modification */ 892 893 /* estimate the size of message */ 894 maxlen = sizeof(*ip6) + sizeof(*nd_na); 895 maxlen += (sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7; 896 if (max_linkhdr + maxlen >= MCLBYTES) { 897 #ifdef DIAGNOSTIC 898 printf("nd6_na_output: max_linkhdr + maxlen >= MCLBYTES " 899 "(%d + %d > %d)\n", max_linkhdr, maxlen, MCLBYTES); 900 #endif 901 return; 902 } 903 904 MGETHDR(m, M_DONTWAIT, MT_DATA); 905 if (m && max_linkhdr + maxlen >= MHLEN) { 906 MCLGET(m, M_DONTWAIT); 907 if ((m->m_flags & M_EXT) == 0) { 908 m_free(m); 909 m = NULL; 910 } 911 } 912 if (m == NULL) 913 return; 914 m->m_pkthdr.rcvif = NULL; 915 916 if (IN6_IS_ADDR_MULTICAST(&daddr6)) { 917 m->m_flags |= M_MCAST; 918 im6o.im6o_multicast_ifp = ifp; 919 im6o.im6o_multicast_hlim = 255; 920 im6o.im6o_multicast_loop = 0; 921 } 922 923 icmp6len = sizeof(*nd_na); 924 m->m_pkthdr.len = m->m_len = sizeof(struct ip6_hdr) + icmp6len; 925 m->m_data += max_linkhdr; /* or MH_ALIGN() equivalent? */ 926 927 /* fill neighbor advertisement packet */ 928 ip6 = mtod(m, struct ip6_hdr *); 929 ip6->ip6_flow = 0; 930 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 931 ip6->ip6_vfc |= IPV6_VERSION; 932 ip6->ip6_nxt = IPPROTO_ICMPV6; 933 ip6->ip6_hlim = 255; 934 if (IN6_IS_ADDR_UNSPECIFIED(&daddr6)) { 935 /* reply to DAD */ 936 daddr6.s6_addr16[0] = IPV6_ADDR_INT16_MLL; 937 daddr6.s6_addr16[1] = 0; 938 daddr6.s6_addr32[1] = 0; 939 daddr6.s6_addr32[2] = 0; 940 daddr6.s6_addr32[3] = IPV6_ADDR_INT32_ONE; 941 if (in6_setscope(&daddr6, ifp, NULL)) 942 goto bad; 943 944 flags &= ~ND_NA_FLAG_SOLICITED; 945 } 946 ip6->ip6_dst = daddr6; 947 bzero(&dst_sa, sizeof(struct sockaddr_in6)); 948 dst_sa.sin6_family = AF_INET6; 949 dst_sa.sin6_len = sizeof(struct sockaddr_in6); 950 dst_sa.sin6_addr = daddr6; 951 952 /* 953 * Select a source whose scope is the same as that of the dest. 954 */ 955 bcopy(&dst_sa, &ro.ro_dst, sizeof(dst_sa)); 956 src = in6_selectsrc(&dst_sa, NULL, NULL, &ro, NULL, NULL, &error); 957 if (src == NULL) { 958 char ip6buf[INET6_ADDRSTRLEN]; 959 nd6log((LOG_DEBUG, "nd6_na_output: source can't be " 960 "determined: dst=%s, error=%d\n", 961 ip6_sprintf(ip6buf, &dst_sa.sin6_addr), error)); 962 goto bad; 963 } 964 ip6->ip6_src = *src; 965 nd_na = (struct nd_neighbor_advert *)(ip6 + 1); 966 nd_na->nd_na_type = ND_NEIGHBOR_ADVERT; 967 nd_na->nd_na_code = 0; 968 nd_na->nd_na_target = *taddr6; 969 in6_clearscope(&nd_na->nd_na_target); /* XXX */ 970 971 /* 972 * "tlladdr" indicates NS's condition for adding tlladdr or not. 973 * see nd6_ns_input() for details. 974 * Basically, if NS packet is sent to unicast/anycast addr, 975 * target lladdr option SHOULD NOT be included. 976 */ 977 if (tlladdr) { 978 /* 979 * sdl0 != NULL indicates proxy NA. If we do proxy, use 980 * lladdr in sdl0. If we are not proxying (sending NA for 981 * my address) use lladdr configured for the interface. 982 */ 983 if (sdl0 == NULL) { 984 #ifdef DEV_CARP 985 if (ifp->if_carp) 986 mac = carp_macmatch6(ifp->if_carp, m, taddr6); 987 if (mac == NULL) 988 mac = nd6_ifptomac(ifp); 989 #else 990 mac = nd6_ifptomac(ifp); 991 #endif 992 } else if (sdl0->sa_family == AF_LINK) { 993 struct sockaddr_dl *sdl; 994 sdl = (struct sockaddr_dl *)sdl0; 995 if (sdl->sdl_alen == ifp->if_addrlen) 996 mac = LLADDR(sdl); 997 } 998 } 999 if (tlladdr && mac) { 1000 int optlen = sizeof(struct nd_opt_hdr) + ifp->if_addrlen; 1001 struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)(nd_na + 1); 1002 1003 /* roundup to 8 bytes alignment! */ 1004 optlen = (optlen + 7) & ~7; 1005 1006 m->m_pkthdr.len += optlen; 1007 m->m_len += optlen; 1008 icmp6len += optlen; 1009 bzero((caddr_t)nd_opt, optlen); 1010 nd_opt->nd_opt_type = ND_OPT_TARGET_LINKADDR; 1011 nd_opt->nd_opt_len = optlen >> 3; 1012 bcopy(mac, (caddr_t)(nd_opt + 1), ifp->if_addrlen); 1013 } else 1014 flags &= ~ND_NA_FLAG_OVERRIDE; 1015 1016 ip6->ip6_plen = htons((u_short)icmp6len); 1017 nd_na->nd_na_flags_reserved = flags; 1018 nd_na->nd_na_cksum = 0; 1019 nd_na->nd_na_cksum = 1020 in6_cksum(m, IPPROTO_ICMPV6, sizeof(struct ip6_hdr), icmp6len); 1021 1022 ip6_output(m, NULL, &ro, 0, &im6o, NULL, NULL); 1023 icmp6_ifstat_inc(ifp, ifs6_out_msg); 1024 icmp6_ifstat_inc(ifp, ifs6_out_neighboradvert); 1025 V_icmp6stat.icp6s_outhist[ND_NEIGHBOR_ADVERT]++; 1026 1027 if (ro.ro_rt) { /* we don't cache this route. */ 1028 RTFREE(ro.ro_rt); 1029 } 1030 return; 1031 1032 bad: 1033 if (ro.ro_rt) { 1034 RTFREE(ro.ro_rt); 1035 } 1036 m_freem(m); 1037 return; 1038 } 1039 1040 caddr_t 1041 nd6_ifptomac(struct ifnet *ifp) 1042 { 1043 switch (ifp->if_type) { 1044 case IFT_ARCNET: 1045 case IFT_ETHER: 1046 case IFT_FDDI: 1047 case IFT_IEEE1394: 1048 #ifdef IFT_L2VLAN 1049 case IFT_L2VLAN: 1050 #endif 1051 #ifdef IFT_IEEE80211 1052 case IFT_IEEE80211: 1053 #endif 1054 #ifdef IFT_CARP 1055 case IFT_CARP: 1056 #endif 1057 case IFT_BRIDGE: 1058 case IFT_ISO88025: 1059 return IF_LLADDR(ifp); 1060 default: 1061 return NULL; 1062 } 1063 } 1064 1065 TAILQ_HEAD(dadq_head, dadq); 1066 struct dadq { 1067 TAILQ_ENTRY(dadq) dad_list; 1068 struct ifaddr *dad_ifa; 1069 int dad_count; /* max NS to send */ 1070 int dad_ns_tcount; /* # of trials to send NS */ 1071 int dad_ns_ocount; /* NS sent so far */ 1072 int dad_ns_icount; 1073 int dad_na_icount; 1074 struct callout dad_timer_ch; 1075 }; 1076 1077 static struct dadq_head dadq; 1078 static int dad_init = 0; 1079 1080 static struct dadq * 1081 nd6_dad_find(struct ifaddr *ifa) 1082 { 1083 struct dadq *dp; 1084 1085 for (dp = V_dadq.tqh_first; dp; dp = dp->dad_list.tqe_next) { 1086 if (dp->dad_ifa == ifa) 1087 return dp; 1088 } 1089 return NULL; 1090 } 1091 1092 static void 1093 nd6_dad_starttimer(struct dadq *dp, int ticks) 1094 { 1095 1096 callout_reset(&dp->dad_timer_ch, ticks, 1097 (void (*)(void *))nd6_dad_timer, (void *)dp->dad_ifa); 1098 } 1099 1100 static void 1101 nd6_dad_stoptimer(struct dadq *dp) 1102 { 1103 1104 callout_stop(&dp->dad_timer_ch); 1105 } 1106 1107 /* 1108 * Start Duplicate Address Detection (DAD) for specified interface address. 1109 */ 1110 void 1111 nd6_dad_start(struct ifaddr *ifa, int delay) 1112 { 1113 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1114 struct dadq *dp; 1115 char ip6buf[INET6_ADDRSTRLEN]; 1116 1117 if (!V_dad_init) { 1118 TAILQ_INIT(&V_dadq); 1119 V_dad_init++; 1120 } 1121 1122 /* 1123 * If we don't need DAD, don't do it. 1124 * There are several cases: 1125 * - DAD is disabled (ip6_dad_count == 0) 1126 * - the interface address is anycast 1127 */ 1128 if (!(ia->ia6_flags & IN6_IFF_TENTATIVE)) { 1129 log(LOG_DEBUG, 1130 "nd6_dad_start: called with non-tentative address " 1131 "%s(%s)\n", 1132 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr), 1133 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1134 return; 1135 } 1136 if (ia->ia6_flags & IN6_IFF_ANYCAST) { 1137 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1138 return; 1139 } 1140 if (!V_ip6_dad_count) { 1141 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1142 return; 1143 } 1144 if (ifa->ifa_ifp == NULL) 1145 panic("nd6_dad_start: ifa->ifa_ifp == NULL"); 1146 if (!(ifa->ifa_ifp->if_flags & IFF_UP)) { 1147 return; 1148 } 1149 if (nd6_dad_find(ifa) != NULL) { 1150 /* DAD already in progress */ 1151 return; 1152 } 1153 1154 dp = malloc(sizeof(*dp), M_IP6NDP, M_NOWAIT); 1155 if (dp == NULL) { 1156 log(LOG_ERR, "nd6_dad_start: memory allocation failed for " 1157 "%s(%s)\n", 1158 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr), 1159 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1160 return; 1161 } 1162 bzero(dp, sizeof(*dp)); 1163 callout_init(&dp->dad_timer_ch, 0); 1164 TAILQ_INSERT_TAIL(&dadq, (struct dadq *)dp, dad_list); 1165 1166 nd6log((LOG_DEBUG, "%s: starting DAD for %s\n", if_name(ifa->ifa_ifp), 1167 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr))); 1168 1169 /* 1170 * Send NS packet for DAD, ip6_dad_count times. 1171 * Note that we must delay the first transmission, if this is the 1172 * first packet to be sent from the interface after interface 1173 * (re)initialization. 1174 */ 1175 dp->dad_ifa = ifa; 1176 IFAREF(ifa); /* just for safety */ 1177 dp->dad_count = V_ip6_dad_count; 1178 dp->dad_ns_icount = dp->dad_na_icount = 0; 1179 dp->dad_ns_ocount = dp->dad_ns_tcount = 0; 1180 if (delay == 0) { 1181 nd6_dad_ns_output(dp, ifa); 1182 nd6_dad_starttimer(dp, 1183 (long)ND_IFINFO(ifa->ifa_ifp)->retrans * hz / 1000); 1184 } else { 1185 nd6_dad_starttimer(dp, delay); 1186 } 1187 } 1188 1189 /* 1190 * terminate DAD unconditionally. used for address removals. 1191 */ 1192 void 1193 nd6_dad_stop(struct ifaddr *ifa) 1194 { 1195 struct dadq *dp; 1196 1197 if (!V_dad_init) 1198 return; 1199 dp = nd6_dad_find(ifa); 1200 if (!dp) { 1201 /* DAD wasn't started yet */ 1202 return; 1203 } 1204 1205 nd6_dad_stoptimer(dp); 1206 1207 TAILQ_REMOVE(&V_dadq, (struct dadq *)dp, dad_list); 1208 free(dp, M_IP6NDP); 1209 dp = NULL; 1210 IFAFREE(ifa); 1211 } 1212 1213 static void 1214 nd6_dad_timer(struct ifaddr *ifa) 1215 { 1216 int s; 1217 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1218 struct dadq *dp; 1219 char ip6buf[INET6_ADDRSTRLEN]; 1220 1221 s = splnet(); /* XXX */ 1222 1223 /* Sanity check */ 1224 if (ia == NULL) { 1225 log(LOG_ERR, "nd6_dad_timer: called with null parameter\n"); 1226 goto done; 1227 } 1228 dp = nd6_dad_find(ifa); 1229 if (dp == NULL) { 1230 log(LOG_ERR, "nd6_dad_timer: DAD structure not found\n"); 1231 goto done; 1232 } 1233 if (ia->ia6_flags & IN6_IFF_DUPLICATED) { 1234 log(LOG_ERR, "nd6_dad_timer: called with duplicated address " 1235 "%s(%s)\n", 1236 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr), 1237 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1238 goto done; 1239 } 1240 if ((ia->ia6_flags & IN6_IFF_TENTATIVE) == 0) { 1241 log(LOG_ERR, "nd6_dad_timer: called with non-tentative address " 1242 "%s(%s)\n", 1243 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr), 1244 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1245 goto done; 1246 } 1247 1248 /* timeouted with IFF_{RUNNING,UP} check */ 1249 if (dp->dad_ns_tcount > V_dad_maxtry) { 1250 nd6log((LOG_INFO, "%s: could not run DAD, driver problem?\n", 1251 if_name(ifa->ifa_ifp))); 1252 1253 TAILQ_REMOVE(&V_dadq, (struct dadq *)dp, dad_list); 1254 free(dp, M_IP6NDP); 1255 dp = NULL; 1256 IFAFREE(ifa); 1257 goto done; 1258 } 1259 1260 /* Need more checks? */ 1261 if (dp->dad_ns_ocount < dp->dad_count) { 1262 /* 1263 * We have more NS to go. Send NS packet for DAD. 1264 */ 1265 nd6_dad_ns_output(dp, ifa); 1266 nd6_dad_starttimer(dp, 1267 (long)ND_IFINFO(ifa->ifa_ifp)->retrans * hz / 1000); 1268 } else { 1269 /* 1270 * We have transmitted sufficient number of DAD packets. 1271 * See what we've got. 1272 */ 1273 int duplicate; 1274 1275 duplicate = 0; 1276 1277 if (dp->dad_na_icount) { 1278 /* 1279 * the check is in nd6_dad_na_input(), 1280 * but just in case 1281 */ 1282 duplicate++; 1283 } 1284 1285 if (dp->dad_ns_icount) { 1286 /* We've seen NS, means DAD has failed. */ 1287 duplicate++; 1288 } 1289 1290 if (duplicate) { 1291 /* (*dp) will be freed in nd6_dad_duplicated() */ 1292 dp = NULL; 1293 nd6_dad_duplicated(ifa); 1294 } else { 1295 /* 1296 * We are done with DAD. No NA came, no NS came. 1297 * No duplicate address found. 1298 */ 1299 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1300 1301 nd6log((LOG_DEBUG, 1302 "%s: DAD complete for %s - no duplicates found\n", 1303 if_name(ifa->ifa_ifp), 1304 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr))); 1305 1306 TAILQ_REMOVE(&V_dadq, (struct dadq *)dp, dad_list); 1307 free(dp, M_IP6NDP); 1308 dp = NULL; 1309 IFAFREE(ifa); 1310 } 1311 } 1312 1313 done: 1314 splx(s); 1315 } 1316 1317 void 1318 nd6_dad_duplicated(struct ifaddr *ifa) 1319 { 1320 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1321 struct ifnet *ifp; 1322 struct dadq *dp; 1323 char ip6buf[INET6_ADDRSTRLEN]; 1324 1325 dp = nd6_dad_find(ifa); 1326 if (dp == NULL) { 1327 log(LOG_ERR, "nd6_dad_duplicated: DAD structure not found\n"); 1328 return; 1329 } 1330 1331 log(LOG_ERR, "%s: DAD detected duplicate IPv6 address %s: " 1332 "NS in/out=%d/%d, NA in=%d\n", 1333 if_name(ifa->ifa_ifp), ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr), 1334 dp->dad_ns_icount, dp->dad_ns_ocount, dp->dad_na_icount); 1335 1336 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1337 ia->ia6_flags |= IN6_IFF_DUPLICATED; 1338 1339 /* We are done with DAD, with duplicate address found. (failure) */ 1340 nd6_dad_stoptimer(dp); 1341 1342 ifp = ifa->ifa_ifp; 1343 log(LOG_ERR, "%s: DAD complete for %s - duplicate found\n", 1344 if_name(ifp), ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr)); 1345 log(LOG_ERR, "%s: manual intervention required\n", 1346 if_name(ifp)); 1347 1348 /* 1349 * If the address is a link-local address formed from an interface 1350 * identifier based on the hardware address which is supposed to be 1351 * uniquely assigned (e.g., EUI-64 for an Ethernet interface), IP 1352 * operation on the interface SHOULD be disabled. 1353 * [rfc2462bis-03 Section 5.4.5] 1354 */ 1355 if (IN6_IS_ADDR_LINKLOCAL(&ia->ia_addr.sin6_addr)) { 1356 struct in6_addr in6; 1357 1358 /* 1359 * To avoid over-reaction, we only apply this logic when we are 1360 * very sure that hardware addresses are supposed to be unique. 1361 */ 1362 switch (ifp->if_type) { 1363 case IFT_ETHER: 1364 case IFT_FDDI: 1365 case IFT_ATM: 1366 case IFT_IEEE1394: 1367 #ifdef IFT_IEEE80211 1368 case IFT_IEEE80211: 1369 #endif 1370 in6 = ia->ia_addr.sin6_addr; 1371 if (in6_get_hw_ifid(ifp, &in6) == 0 && 1372 IN6_ARE_ADDR_EQUAL(&ia->ia_addr.sin6_addr, &in6)) { 1373 ND_IFINFO(ifp)->flags |= ND6_IFF_IFDISABLED; 1374 log(LOG_ERR, "%s: possible hardware address " 1375 "duplication detected, disable IPv6\n", 1376 if_name(ifp)); 1377 } 1378 break; 1379 } 1380 } 1381 1382 TAILQ_REMOVE(&V_dadq, (struct dadq *)dp, dad_list); 1383 free(dp, M_IP6NDP); 1384 dp = NULL; 1385 IFAFREE(ifa); 1386 } 1387 1388 static void 1389 nd6_dad_ns_output(struct dadq *dp, struct ifaddr *ifa) 1390 { 1391 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1392 struct ifnet *ifp = ifa->ifa_ifp; 1393 1394 dp->dad_ns_tcount++; 1395 if ((ifp->if_flags & IFF_UP) == 0) { 1396 return; 1397 } 1398 if ((ifp->if_drv_flags & IFF_DRV_RUNNING) == 0) { 1399 return; 1400 } 1401 1402 dp->dad_ns_ocount++; 1403 nd6_ns_output(ifp, NULL, &ia->ia_addr.sin6_addr, NULL, 1); 1404 } 1405 1406 static void 1407 nd6_dad_ns_input(struct ifaddr *ifa) 1408 { 1409 struct in6_ifaddr *ia; 1410 struct ifnet *ifp; 1411 const struct in6_addr *taddr6; 1412 struct dadq *dp; 1413 int duplicate; 1414 1415 if (ifa == NULL) 1416 panic("ifa == NULL in nd6_dad_ns_input"); 1417 1418 ia = (struct in6_ifaddr *)ifa; 1419 ifp = ifa->ifa_ifp; 1420 taddr6 = &ia->ia_addr.sin6_addr; 1421 duplicate = 0; 1422 dp = nd6_dad_find(ifa); 1423 1424 /* Quickhack - completely ignore DAD NS packets */ 1425 if (V_dad_ignore_ns) { 1426 char ip6buf[INET6_ADDRSTRLEN]; 1427 nd6log((LOG_INFO, 1428 "nd6_dad_ns_input: ignoring DAD NS packet for " 1429 "address %s(%s)\n", ip6_sprintf(ip6buf, taddr6), 1430 if_name(ifa->ifa_ifp))); 1431 return; 1432 } 1433 1434 /* 1435 * if I'm yet to start DAD, someone else started using this address 1436 * first. I have a duplicate and you win. 1437 */ 1438 if (dp == NULL || dp->dad_ns_ocount == 0) 1439 duplicate++; 1440 1441 /* XXX more checks for loopback situation - see nd6_dad_timer too */ 1442 1443 if (duplicate) { 1444 dp = NULL; /* will be freed in nd6_dad_duplicated() */ 1445 nd6_dad_duplicated(ifa); 1446 } else { 1447 /* 1448 * not sure if I got a duplicate. 1449 * increment ns count and see what happens. 1450 */ 1451 if (dp) 1452 dp->dad_ns_icount++; 1453 } 1454 } 1455 1456 static void 1457 nd6_dad_na_input(struct ifaddr *ifa) 1458 { 1459 struct dadq *dp; 1460 1461 if (ifa == NULL) 1462 panic("ifa == NULL in nd6_dad_na_input"); 1463 1464 dp = nd6_dad_find(ifa); 1465 if (dp) 1466 dp->dad_na_icount++; 1467 1468 /* remove the address. */ 1469 nd6_dad_duplicated(ifa); 1470 } 1471