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 54 #include <net/if.h> 55 #include <net/if_types.h> 56 #include <net/if_dl.h> 57 #include <net/if_var.h> 58 #include <net/route.h> 59 #ifdef RADIX_MPATH 60 #include <net/radix_mpath.h> 61 #endif 62 63 #include <netinet/in.h> 64 #include <netinet/in_var.h> 65 #include <netinet6/in6_var.h> 66 #include <netinet6/in6_ifattach.h> 67 #include <netinet/ip6.h> 68 #include <netinet6/ip6_var.h> 69 #include <netinet6/scope6_var.h> 70 #include <netinet6/nd6.h> 71 #include <netinet/icmp6.h> 72 73 #ifdef DEV_CARP 74 #include <netinet/ip_carp.h> 75 #endif 76 77 #define SDL(s) ((struct sockaddr_dl *)s) 78 79 struct dadq; 80 static struct dadq *nd6_dad_find(struct ifaddr *); 81 static void nd6_dad_starttimer(struct dadq *, int); 82 static void nd6_dad_stoptimer(struct dadq *); 83 static void nd6_dad_timer(struct ifaddr *); 84 static void nd6_dad_ns_output(struct dadq *, struct ifaddr *); 85 static void nd6_dad_ns_input(struct ifaddr *); 86 static void nd6_dad_na_input(struct ifaddr *); 87 88 static int dad_ignore_ns = 0; /* ignore NS in DAD - specwise incorrect*/ 89 static int dad_maxtry = 15; /* max # of *tries* to transmit DAD packet */ 90 91 /* 92 * Input a Neighbor Solicitation Message. 93 * 94 * Based on RFC 2461 95 * Based on RFC 2462 (duplicate address detection) 96 */ 97 void 98 nd6_ns_input(struct mbuf *m, int off, int icmp6len) 99 { 100 struct ifnet *ifp = m->m_pkthdr.rcvif; 101 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 102 struct nd_neighbor_solicit *nd_ns; 103 struct in6_addr saddr6 = ip6->ip6_src; 104 struct in6_addr daddr6 = ip6->ip6_dst; 105 struct in6_addr taddr6; 106 struct in6_addr myaddr6; 107 char *lladdr = NULL; 108 struct ifaddr *ifa = NULL; 109 int lladdrlen = 0; 110 int anycast = 0, proxy = 0, tentative = 0; 111 int tlladdr; 112 union nd_opts ndopts; 113 struct sockaddr_dl *proxydl = NULL; 114 char ip6bufs[INET6_ADDRSTRLEN], ip6bufd[INET6_ADDRSTRLEN]; 115 116 #ifndef PULLDOWN_TEST 117 IP6_EXTHDR_CHECK(m, off, icmp6len,); 118 nd_ns = (struct nd_neighbor_solicit *)((caddr_t)ip6 + off); 119 #else 120 IP6_EXTHDR_GET(nd_ns, struct nd_neighbor_solicit *, m, off, icmp6len); 121 if (nd_ns == NULL) { 122 icmp6stat.icp6s_tooshort++; 123 return; 124 } 125 #endif 126 ip6 = mtod(m, struct ip6_hdr *); /* adjust pointer for safety */ 127 taddr6 = nd_ns->nd_ns_target; 128 if (in6_setscope(&taddr6, ifp, NULL) != 0) 129 goto bad; 130 131 if (ip6->ip6_hlim != 255) { 132 nd6log((LOG_ERR, 133 "nd6_ns_input: invalid hlim (%d) from %s to %s on %s\n", 134 ip6->ip6_hlim, ip6_sprintf(ip6bufs, &ip6->ip6_src), 135 ip6_sprintf(ip6bufd, &ip6->ip6_dst), if_name(ifp))); 136 goto bad; 137 } 138 139 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) { 140 /* dst has to be a solicited node multicast address. */ 141 if (daddr6.s6_addr16[0] == IPV6_ADDR_INT16_MLL && 142 /* don't check ifindex portion */ 143 daddr6.s6_addr32[1] == 0 && 144 daddr6.s6_addr32[2] == IPV6_ADDR_INT32_ONE && 145 daddr6.s6_addr8[12] == 0xff) { 146 ; /* good */ 147 } else { 148 nd6log((LOG_INFO, "nd6_ns_input: bad DAD packet " 149 "(wrong ip6 dst)\n")); 150 goto bad; 151 } 152 } 153 154 if (IN6_IS_ADDR_MULTICAST(&taddr6)) { 155 nd6log((LOG_INFO, "nd6_ns_input: bad NS target (multicast)\n")); 156 goto bad; 157 } 158 159 icmp6len -= sizeof(*nd_ns); 160 nd6_option_init(nd_ns + 1, icmp6len, &ndopts); 161 if (nd6_options(&ndopts) < 0) { 162 nd6log((LOG_INFO, 163 "nd6_ns_input: invalid ND option, ignored\n")); 164 /* nd6_options have incremented stats */ 165 goto freeit; 166 } 167 168 if (ndopts.nd_opts_src_lladdr) { 169 lladdr = (char *)(ndopts.nd_opts_src_lladdr + 1); 170 lladdrlen = ndopts.nd_opts_src_lladdr->nd_opt_len << 3; 171 } 172 173 if (IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_src) && lladdr) { 174 nd6log((LOG_INFO, "nd6_ns_input: bad DAD packet " 175 "(link-layer address option)\n")); 176 goto bad; 177 } 178 179 /* 180 * Attaching target link-layer address to the NA? 181 * (RFC 2461 7.2.4) 182 * 183 * NS IP dst is unicast/anycast MUST NOT add 184 * NS IP dst is solicited-node multicast MUST add 185 * 186 * In implementation, we add target link-layer address by default. 187 * We do not add one in MUST NOT cases. 188 */ 189 if (!IN6_IS_ADDR_MULTICAST(&daddr6)) 190 tlladdr = 0; 191 else 192 tlladdr = 1; 193 194 /* 195 * Target address (taddr6) must be either: 196 * (1) Valid unicast/anycast address for my receiving interface, 197 * (2) Unicast address for which I'm offering proxy service, or 198 * (3) "tentative" address on which DAD is being performed. 199 */ 200 /* (1) and (3) check. */ 201 #ifdef DEV_CARP 202 if (ifp->if_carp) 203 ifa = carp_iamatch6(ifp->if_carp, &taddr6); 204 if (ifa == NULL) 205 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &taddr6); 206 #else 207 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &taddr6); 208 #endif 209 210 /* (2) check. */ 211 if (ifa == NULL) { 212 struct rtentry *rt; 213 struct sockaddr_in6 tsin6; 214 int need_proxy; 215 #ifdef RADIX_MPATH 216 struct route_in6 ro; 217 #endif 218 219 bzero(&tsin6, sizeof tsin6); 220 tsin6.sin6_len = sizeof(struct sockaddr_in6); 221 tsin6.sin6_family = AF_INET6; 222 tsin6.sin6_addr = taddr6; 223 224 #ifdef RADIX_MPATH 225 bzero(&ro, sizeof(ro)); 226 ro.ro_dst = tsin6; 227 rtalloc_mpath((struct route *)&ro, RTF_ANNOUNCE); 228 rt = ro.ro_rt; 229 #else 230 rt = rtalloc1((struct sockaddr *)&tsin6, 0, 0); 231 #endif 232 need_proxy = (rt && (rt->rt_flags & RTF_ANNOUNCE) != 0 && 233 rt->rt_gateway->sa_family == AF_LINK); 234 if (rt) 235 rtfree(rt); 236 if (need_proxy) { 237 /* 238 * proxy NDP for single entry 239 */ 240 ifa = (struct ifaddr *)in6ifa_ifpforlinklocal(ifp, 241 IN6_IFF_NOTREADY|IN6_IFF_ANYCAST); 242 if (ifa) { 243 proxy = 1; 244 proxydl = SDL(rt->rt_gateway); 245 } 246 } 247 } 248 if (ifa == NULL) { 249 /* 250 * We've got an NS packet, and we don't have that adddress 251 * assigned for us. We MUST silently ignore it. 252 * See RFC2461 7.2.3. 253 */ 254 goto freeit; 255 } 256 myaddr6 = *IFA_IN6(ifa); 257 anycast = ((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_ANYCAST; 258 tentative = ((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_TENTATIVE; 259 if (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_DUPLICATED) 260 goto freeit; 261 262 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) { 263 nd6log((LOG_INFO, "nd6_ns_input: lladdrlen mismatch for %s " 264 "(if %d, NS packet %d)\n", 265 ip6_sprintf(ip6bufs, &taddr6), 266 ifp->if_addrlen, lladdrlen - 2)); 267 goto bad; 268 } 269 270 if (IN6_ARE_ADDR_EQUAL(&myaddr6, &saddr6)) { 271 nd6log((LOG_INFO, "nd6_ns_input: duplicate IP6 address %s\n", 272 ip6_sprintf(ip6bufs, &saddr6))); 273 goto freeit; 274 } 275 276 /* 277 * We have neighbor solicitation packet, with target address equals to 278 * one of my tentative address. 279 * 280 * src addr how to process? 281 * --- --- 282 * multicast of course, invalid (rejected in ip6_input) 283 * unicast somebody is doing address resolution -> ignore 284 * unspec dup address detection 285 * 286 * The processing is defined in RFC 2462. 287 */ 288 if (tentative) { 289 /* 290 * If source address is unspecified address, it is for 291 * duplicate address detection. 292 * 293 * If not, the packet is for addess resolution; 294 * silently ignore it. 295 */ 296 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) 297 nd6_dad_ns_input(ifa); 298 299 goto freeit; 300 } 301 302 /* 303 * If the source address is unspecified address, entries must not 304 * be created or updated. 305 * It looks that sender is performing DAD. Output NA toward 306 * all-node multicast address, to tell the sender that I'm using 307 * the address. 308 * S bit ("solicited") must be zero. 309 */ 310 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) { 311 struct in6_addr in6_all; 312 313 in6_all = in6addr_linklocal_allnodes; 314 if (in6_setscope(&in6_all, ifp, NULL) != 0) 315 goto bad; 316 nd6_na_output(ifp, &in6_all, &taddr6, 317 ((anycast || proxy || !tlladdr) ? 0 : ND_NA_FLAG_OVERRIDE) | 318 (ip6_forwarding ? ND_NA_FLAG_ROUTER : 0), 319 tlladdr, (struct sockaddr *)proxydl); 320 goto freeit; 321 } 322 323 nd6_cache_lladdr(ifp, &saddr6, lladdr, lladdrlen, 324 ND_NEIGHBOR_SOLICIT, 0); 325 326 nd6_na_output(ifp, &saddr6, &taddr6, 327 ((anycast || proxy || !tlladdr) ? 0 : ND_NA_FLAG_OVERRIDE) | 328 (ip6_forwarding ? ND_NA_FLAG_ROUTER : 0) | ND_NA_FLAG_SOLICITED, 329 tlladdr, (struct sockaddr *)proxydl); 330 freeit: 331 m_freem(m); 332 return; 333 334 bad: 335 nd6log((LOG_ERR, "nd6_ns_input: src=%s\n", 336 ip6_sprintf(ip6bufs, &saddr6))); 337 nd6log((LOG_ERR, "nd6_ns_input: dst=%s\n", 338 ip6_sprintf(ip6bufs, &daddr6))); 339 nd6log((LOG_ERR, "nd6_ns_input: tgt=%s\n", 340 ip6_sprintf(ip6bufs, &taddr6))); 341 icmp6stat.icp6s_badns++; 342 m_freem(m); 343 } 344 345 /* 346 * Output a Neighbor Solicitation Message. Caller specifies: 347 * - ICMP6 header source IP6 address 348 * - ND6 header target IP6 address 349 * - ND6 header source datalink address 350 * 351 * Based on RFC 2461 352 * Based on RFC 2462 (duplicate address detection) 353 * 354 * ln - for source address determination 355 * dad - duplicate address detection 356 */ 357 void 358 nd6_ns_output(struct ifnet *ifp, const struct in6_addr *daddr6, 359 const struct in6_addr *taddr6, struct llinfo_nd6 *ln, int dad) 360 { 361 struct mbuf *m; 362 struct ip6_hdr *ip6; 363 struct nd_neighbor_solicit *nd_ns; 364 struct in6_addr *src, src_in; 365 struct ip6_moptions im6o; 366 int icmp6len; 367 int maxlen; 368 caddr_t mac; 369 struct route_in6 ro; 370 371 bzero(&ro, sizeof(ro)); 372 373 if (IN6_IS_ADDR_MULTICAST(taddr6)) 374 return; 375 376 /* estimate the size of message */ 377 maxlen = sizeof(*ip6) + sizeof(*nd_ns); 378 maxlen += (sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7; 379 if (max_linkhdr + maxlen >= MCLBYTES) { 380 #ifdef DIAGNOSTIC 381 printf("nd6_ns_output: max_linkhdr + maxlen >= MCLBYTES " 382 "(%d + %d > %d)\n", max_linkhdr, maxlen, MCLBYTES); 383 #endif 384 return; 385 } 386 387 MGETHDR(m, M_DONTWAIT, MT_DATA); 388 if (m && max_linkhdr + maxlen >= MHLEN) { 389 MCLGET(m, M_DONTWAIT); 390 if ((m->m_flags & M_EXT) == 0) { 391 m_free(m); 392 m = NULL; 393 } 394 } 395 if (m == NULL) 396 return; 397 m->m_pkthdr.rcvif = NULL; 398 399 if (daddr6 == NULL || IN6_IS_ADDR_MULTICAST(daddr6)) { 400 m->m_flags |= M_MCAST; 401 im6o.im6o_multicast_ifp = ifp; 402 im6o.im6o_multicast_hlim = 255; 403 im6o.im6o_multicast_loop = 0; 404 } 405 406 icmp6len = sizeof(*nd_ns); 407 m->m_pkthdr.len = m->m_len = sizeof(*ip6) + icmp6len; 408 m->m_data += max_linkhdr; /* or MH_ALIGN() equivalent? */ 409 410 /* fill neighbor solicitation packet */ 411 ip6 = mtod(m, struct ip6_hdr *); 412 ip6->ip6_flow = 0; 413 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 414 ip6->ip6_vfc |= IPV6_VERSION; 415 /* ip6->ip6_plen will be set later */ 416 ip6->ip6_nxt = IPPROTO_ICMPV6; 417 ip6->ip6_hlim = 255; 418 if (daddr6) 419 ip6->ip6_dst = *daddr6; 420 else { 421 ip6->ip6_dst.s6_addr16[0] = IPV6_ADDR_INT16_MLL; 422 ip6->ip6_dst.s6_addr16[1] = 0; 423 ip6->ip6_dst.s6_addr32[1] = 0; 424 ip6->ip6_dst.s6_addr32[2] = IPV6_ADDR_INT32_ONE; 425 ip6->ip6_dst.s6_addr32[3] = taddr6->s6_addr32[3]; 426 ip6->ip6_dst.s6_addr8[12] = 0xff; 427 if (in6_setscope(&ip6->ip6_dst, ifp, NULL) != 0) 428 goto bad; 429 } 430 if (!dad) { 431 /* 432 * RFC2461 7.2.2: 433 * "If the source address of the packet prompting the 434 * solicitation is the same as one of the addresses assigned 435 * to the outgoing interface, that address SHOULD be placed 436 * in the IP Source Address of the outgoing solicitation. 437 * Otherwise, any one of the addresses assigned to the 438 * interface should be used." 439 * 440 * We use the source address for the prompting packet 441 * (saddr6), if: 442 * - saddr6 is given from the caller (by giving "ln"), and 443 * - saddr6 belongs to the outgoing interface. 444 * Otherwise, we perform the source address selection as usual. 445 */ 446 struct ip6_hdr *hip6; /* hold ip6 */ 447 struct in6_addr *hsrc = NULL; 448 449 if (ln && ln->ln_hold) { 450 /* 451 * assuming every packet in ln_hold has the same IP 452 * header 453 */ 454 hip6 = mtod(ln->ln_hold, struct ip6_hdr *); 455 /* XXX pullup? */ 456 if (sizeof(*hip6) < ln->ln_hold->m_len) 457 hsrc = &hip6->ip6_src; 458 else 459 hsrc = NULL; 460 } 461 if (hsrc && in6ifa_ifpwithaddr(ifp, hsrc)) 462 src = hsrc; 463 else { 464 int error; 465 struct sockaddr_in6 dst_sa; 466 467 bzero(&dst_sa, sizeof(dst_sa)); 468 dst_sa.sin6_family = AF_INET6; 469 dst_sa.sin6_len = sizeof(dst_sa); 470 dst_sa.sin6_addr = ip6->ip6_dst; 471 472 src = in6_selectsrc(&dst_sa, NULL, 473 NULL, &ro, NULL, NULL, &error); 474 if (src == NULL) { 475 char ip6buf[INET6_ADDRSTRLEN]; 476 nd6log((LOG_DEBUG, 477 "nd6_ns_output: source can't be " 478 "determined: dst=%s, error=%d\n", 479 ip6_sprintf(ip6buf, &dst_sa.sin6_addr), 480 error)); 481 goto bad; 482 } 483 } 484 } else { 485 /* 486 * Source address for DAD packet must always be IPv6 487 * unspecified address. (0::0) 488 * We actually don't have to 0-clear the address (we did it 489 * above), but we do so here explicitly to make the intention 490 * clearer. 491 */ 492 bzero(&src_in, sizeof(src_in)); 493 src = &src_in; 494 } 495 ip6->ip6_src = *src; 496 nd_ns = (struct nd_neighbor_solicit *)(ip6 + 1); 497 nd_ns->nd_ns_type = ND_NEIGHBOR_SOLICIT; 498 nd_ns->nd_ns_code = 0; 499 nd_ns->nd_ns_reserved = 0; 500 nd_ns->nd_ns_target = *taddr6; 501 in6_clearscope(&nd_ns->nd_ns_target); /* XXX */ 502 503 /* 504 * Add source link-layer address option. 505 * 506 * spec implementation 507 * --- --- 508 * DAD packet MUST NOT do not add the option 509 * there's no link layer address: 510 * impossible do not add the option 511 * there's link layer address: 512 * Multicast NS MUST add one add the option 513 * Unicast NS SHOULD add one add the option 514 */ 515 if (!dad && (mac = nd6_ifptomac(ifp))) { 516 int optlen = sizeof(struct nd_opt_hdr) + ifp->if_addrlen; 517 struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)(nd_ns + 1); 518 /* 8 byte alignments... */ 519 optlen = (optlen + 7) & ~7; 520 521 m->m_pkthdr.len += optlen; 522 m->m_len += optlen; 523 icmp6len += optlen; 524 bzero((caddr_t)nd_opt, optlen); 525 nd_opt->nd_opt_type = ND_OPT_SOURCE_LINKADDR; 526 nd_opt->nd_opt_len = optlen >> 3; 527 bcopy(mac, (caddr_t)(nd_opt + 1), ifp->if_addrlen); 528 } 529 530 ip6->ip6_plen = htons((u_short)icmp6len); 531 nd_ns->nd_ns_cksum = 0; 532 nd_ns->nd_ns_cksum = 533 in6_cksum(m, IPPROTO_ICMPV6, sizeof(*ip6), icmp6len); 534 535 ip6_output(m, NULL, &ro, dad ? IPV6_UNSPECSRC : 0, &im6o, NULL, NULL); 536 icmp6_ifstat_inc(ifp, ifs6_out_msg); 537 icmp6_ifstat_inc(ifp, ifs6_out_neighborsolicit); 538 icmp6stat.icp6s_outhist[ND_NEIGHBOR_SOLICIT]++; 539 540 if (ro.ro_rt) { /* we don't cache this route. */ 541 RTFREE(ro.ro_rt); 542 } 543 return; 544 545 bad: 546 if (ro.ro_rt) { 547 RTFREE(ro.ro_rt); 548 } 549 m_freem(m); 550 return; 551 } 552 553 /* 554 * Neighbor advertisement input handling. 555 * 556 * Based on RFC 2461 557 * Based on RFC 2462 (duplicate address detection) 558 * 559 * the following items are not implemented yet: 560 * - proxy advertisement delay rule (RFC2461 7.2.8, last paragraph, SHOULD) 561 * - anycast advertisement delay rule (RFC2461 7.2.7, SHOULD) 562 */ 563 void 564 nd6_na_input(struct mbuf *m, int off, int icmp6len) 565 { 566 struct ifnet *ifp = m->m_pkthdr.rcvif; 567 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 568 struct nd_neighbor_advert *nd_na; 569 struct in6_addr daddr6 = ip6->ip6_dst; 570 struct in6_addr taddr6; 571 int flags; 572 int is_router; 573 int is_solicited; 574 int is_override; 575 char *lladdr = NULL; 576 int lladdrlen = 0; 577 struct ifaddr *ifa; 578 struct llinfo_nd6 *ln; 579 struct rtentry *rt; 580 struct sockaddr_dl *sdl; 581 union nd_opts ndopts; 582 char ip6bufs[INET6_ADDRSTRLEN], ip6bufd[INET6_ADDRSTRLEN]; 583 584 if (ip6->ip6_hlim != 255) { 585 nd6log((LOG_ERR, 586 "nd6_na_input: invalid hlim (%d) from %s to %s on %s\n", 587 ip6->ip6_hlim, ip6_sprintf(ip6bufs, &ip6->ip6_src), 588 ip6_sprintf(ip6bufd, &ip6->ip6_dst), if_name(ifp))); 589 goto bad; 590 } 591 592 #ifndef PULLDOWN_TEST 593 IP6_EXTHDR_CHECK(m, off, icmp6len,); 594 nd_na = (struct nd_neighbor_advert *)((caddr_t)ip6 + off); 595 #else 596 IP6_EXTHDR_GET(nd_na, struct nd_neighbor_advert *, m, off, icmp6len); 597 if (nd_na == NULL) { 598 icmp6stat.icp6s_tooshort++; 599 return; 600 } 601 #endif 602 603 flags = nd_na->nd_na_flags_reserved; 604 is_router = ((flags & ND_NA_FLAG_ROUTER) != 0); 605 is_solicited = ((flags & ND_NA_FLAG_SOLICITED) != 0); 606 is_override = ((flags & ND_NA_FLAG_OVERRIDE) != 0); 607 608 taddr6 = nd_na->nd_na_target; 609 if (in6_setscope(&taddr6, ifp, NULL)) 610 goto bad; /* XXX: impossible */ 611 612 if (IN6_IS_ADDR_MULTICAST(&taddr6)) { 613 nd6log((LOG_ERR, 614 "nd6_na_input: invalid target address %s\n", 615 ip6_sprintf(ip6bufs, &taddr6))); 616 goto bad; 617 } 618 if (IN6_IS_ADDR_MULTICAST(&daddr6)) 619 if (is_solicited) { 620 nd6log((LOG_ERR, 621 "nd6_na_input: a solicited adv is multicasted\n")); 622 goto bad; 623 } 624 625 icmp6len -= sizeof(*nd_na); 626 nd6_option_init(nd_na + 1, icmp6len, &ndopts); 627 if (nd6_options(&ndopts) < 0) { 628 nd6log((LOG_INFO, 629 "nd6_na_input: invalid ND option, ignored\n")); 630 /* nd6_options have incremented stats */ 631 goto freeit; 632 } 633 634 if (ndopts.nd_opts_tgt_lladdr) { 635 lladdr = (char *)(ndopts.nd_opts_tgt_lladdr + 1); 636 lladdrlen = ndopts.nd_opts_tgt_lladdr->nd_opt_len << 3; 637 } 638 639 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &taddr6); 640 641 /* 642 * Target address matches one of my interface address. 643 * 644 * If my address is tentative, this means that there's somebody 645 * already using the same address as mine. This indicates DAD failure. 646 * This is defined in RFC 2462. 647 * 648 * Otherwise, process as defined in RFC 2461. 649 */ 650 if (ifa 651 && (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_TENTATIVE)) { 652 nd6_dad_na_input(ifa); 653 goto freeit; 654 } 655 656 /* Just for safety, maybe unnecessary. */ 657 if (ifa) { 658 log(LOG_ERR, 659 "nd6_na_input: duplicate IP6 address %s\n", 660 ip6_sprintf(ip6bufs, &taddr6)); 661 goto freeit; 662 } 663 664 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) { 665 nd6log((LOG_INFO, "nd6_na_input: lladdrlen mismatch for %s " 666 "(if %d, NA packet %d)\n", ip6_sprintf(ip6bufs, &taddr6), 667 ifp->if_addrlen, lladdrlen - 2)); 668 goto bad; 669 } 670 671 /* 672 * If no neighbor cache entry is found, NA SHOULD silently be 673 * discarded. 674 */ 675 rt = nd6_lookup(&taddr6, 0, ifp); 676 if ((rt == NULL) || 677 ((ln = (struct llinfo_nd6 *)rt->rt_llinfo) == NULL) || 678 ((sdl = SDL(rt->rt_gateway)) == NULL)) 679 goto freeit; 680 681 if (ln->ln_state == ND6_LLINFO_INCOMPLETE) { 682 /* 683 * If the link-layer has address, and no lladdr option came, 684 * discard the packet. 685 */ 686 if (ifp->if_addrlen && lladdr == NULL) 687 goto freeit; 688 689 /* 690 * Record link-layer address, and update the state. 691 */ 692 sdl->sdl_alen = ifp->if_addrlen; 693 bcopy(lladdr, LLADDR(sdl), ifp->if_addrlen); 694 if (is_solicited) { 695 ln->ln_state = ND6_LLINFO_REACHABLE; 696 ln->ln_byhint = 0; 697 if (!ND6_LLINFO_PERMANENT(ln)) { 698 nd6_llinfo_settimer(ln, 699 (long)ND_IFINFO(rt->rt_ifp)->reachable * hz); 700 } 701 } else { 702 ln->ln_state = ND6_LLINFO_STALE; 703 nd6_llinfo_settimer(ln, (long)nd6_gctimer * hz); 704 } 705 if ((ln->ln_router = is_router) != 0) { 706 /* 707 * This means a router's state has changed from 708 * non-reachable to probably reachable, and might 709 * affect the status of associated prefixes.. 710 */ 711 pfxlist_onlink_check(); 712 } 713 } else { 714 int llchange; 715 716 /* 717 * Check if the link-layer address has changed or not. 718 */ 719 if (lladdr == NULL) 720 llchange = 0; 721 else { 722 if (sdl->sdl_alen) { 723 if (bcmp(lladdr, LLADDR(sdl), ifp->if_addrlen)) 724 llchange = 1; 725 else 726 llchange = 0; 727 } else 728 llchange = 1; 729 } 730 731 /* 732 * This is VERY complex. Look at it with care. 733 * 734 * override solicit lladdr llchange action 735 * (L: record lladdr) 736 * 737 * 0 0 n -- (2c) 738 * 0 0 y n (2b) L 739 * 0 0 y y (1) REACHABLE->STALE 740 * 0 1 n -- (2c) *->REACHABLE 741 * 0 1 y n (2b) L *->REACHABLE 742 * 0 1 y y (1) REACHABLE->STALE 743 * 1 0 n -- (2a) 744 * 1 0 y n (2a) L 745 * 1 0 y y (2a) L *->STALE 746 * 1 1 n -- (2a) *->REACHABLE 747 * 1 1 y n (2a) L *->REACHABLE 748 * 1 1 y y (2a) L *->REACHABLE 749 */ 750 if (!is_override && (lladdr != NULL && llchange)) { /* (1) */ 751 /* 752 * If state is REACHABLE, make it STALE. 753 * no other updates should be done. 754 */ 755 if (ln->ln_state == ND6_LLINFO_REACHABLE) { 756 ln->ln_state = ND6_LLINFO_STALE; 757 nd6_llinfo_settimer(ln, (long)nd6_gctimer * hz); 758 } 759 goto freeit; 760 } else if (is_override /* (2a) */ 761 || (!is_override && (lladdr != NULL && !llchange)) /* (2b) */ 762 || lladdr == NULL) { /* (2c) */ 763 /* 764 * Update link-local address, if any. 765 */ 766 if (lladdr != NULL) { 767 sdl->sdl_alen = ifp->if_addrlen; 768 bcopy(lladdr, LLADDR(sdl), ifp->if_addrlen); 769 } 770 771 /* 772 * If solicited, make the state REACHABLE. 773 * If not solicited and the link-layer address was 774 * changed, make it STALE. 775 */ 776 if (is_solicited) { 777 ln->ln_state = ND6_LLINFO_REACHABLE; 778 ln->ln_byhint = 0; 779 if (!ND6_LLINFO_PERMANENT(ln)) { 780 nd6_llinfo_settimer(ln, 781 (long)ND_IFINFO(ifp)->reachable * hz); 782 } 783 } else { 784 if (lladdr != NULL && llchange) { 785 ln->ln_state = ND6_LLINFO_STALE; 786 nd6_llinfo_settimer(ln, 787 (long)nd6_gctimer * hz); 788 } 789 } 790 } 791 792 if (ln->ln_router && !is_router) { 793 /* 794 * The peer dropped the router flag. 795 * Remove the sender from the Default Router List and 796 * update the Destination Cache entries. 797 */ 798 struct nd_defrouter *dr; 799 struct in6_addr *in6; 800 int s; 801 802 in6 = &((struct sockaddr_in6 *)rt_key(rt))->sin6_addr; 803 804 /* 805 * Lock to protect the default router list. 806 * XXX: this might be unnecessary, since this function 807 * is only called under the network software interrupt 808 * context. However, we keep it just for safety. 809 */ 810 s = splnet(); 811 dr = defrouter_lookup(in6, ifp); 812 if (dr) 813 defrtrlist_del(dr); 814 else if (!ip6_forwarding) { 815 /* 816 * Even if the neighbor is not in the default 817 * router list, the neighbor may be used 818 * as a next hop for some destinations 819 * (e.g. redirect case). So we must 820 * call rt6_flush explicitly. 821 */ 822 rt6_flush(&ip6->ip6_src, ifp); 823 } 824 splx(s); 825 } 826 ln->ln_router = is_router; 827 } 828 rt->rt_flags &= ~RTF_REJECT; 829 ln->ln_asked = 0; 830 if (ln->ln_hold) { 831 struct mbuf *m_hold, *m_hold_next; 832 833 /* 834 * reset the ln_hold in advance, to explicitly 835 * prevent a ln_hold lookup in nd6_output() 836 * (wouldn't happen, though...) 837 */ 838 for (m_hold = ln->ln_hold; 839 m_hold; m_hold = m_hold_next) { 840 m_hold_next = m_hold->m_nextpkt; 841 m_hold->m_nextpkt = NULL; 842 /* 843 * we assume ifp is not a loopback here, so just set 844 * the 2nd argument as the 1st one. 845 */ 846 nd6_output(ifp, ifp, m_hold, 847 (struct sockaddr_in6 *)rt_key(rt), rt); 848 } 849 ln->ln_hold = NULL; 850 } 851 852 freeit: 853 m_freem(m); 854 return; 855 856 bad: 857 icmp6stat.icp6s_badna++; 858 m_freem(m); 859 } 860 861 /* 862 * Neighbor advertisement output handling. 863 * 864 * Based on RFC 2461 865 * 866 * the following items are not implemented yet: 867 * - proxy advertisement delay rule (RFC2461 7.2.8, last paragraph, SHOULD) 868 * - anycast advertisement delay rule (RFC2461 7.2.7, SHOULD) 869 * 870 * tlladdr - 1 if include target link-layer address 871 * sdl0 - sockaddr_dl (= proxy NA) or NULL 872 */ 873 void 874 nd6_na_output(struct ifnet *ifp, const struct in6_addr *daddr6_0, 875 const struct in6_addr *taddr6, u_long flags, int tlladdr, 876 struct sockaddr *sdl0) 877 { 878 struct mbuf *m; 879 struct ip6_hdr *ip6; 880 struct nd_neighbor_advert *nd_na; 881 struct ip6_moptions im6o; 882 struct in6_addr *src, daddr6; 883 struct sockaddr_in6 dst_sa; 884 int icmp6len, maxlen, error; 885 caddr_t mac = NULL; 886 struct route_in6 ro; 887 888 bzero(&ro, sizeof(ro)); 889 890 daddr6 = *daddr6_0; /* make a local copy for modification */ 891 892 /* estimate the size of message */ 893 maxlen = sizeof(*ip6) + sizeof(*nd_na); 894 maxlen += (sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7; 895 if (max_linkhdr + maxlen >= MCLBYTES) { 896 #ifdef DIAGNOSTIC 897 printf("nd6_na_output: max_linkhdr + maxlen >= MCLBYTES " 898 "(%d + %d > %d)\n", max_linkhdr, maxlen, MCLBYTES); 899 #endif 900 return; 901 } 902 903 MGETHDR(m, M_DONTWAIT, MT_DATA); 904 if (m && max_linkhdr + maxlen >= MHLEN) { 905 MCLGET(m, M_DONTWAIT); 906 if ((m->m_flags & M_EXT) == 0) { 907 m_free(m); 908 m = NULL; 909 } 910 } 911 if (m == NULL) 912 return; 913 m->m_pkthdr.rcvif = NULL; 914 915 if (IN6_IS_ADDR_MULTICAST(&daddr6)) { 916 m->m_flags |= M_MCAST; 917 im6o.im6o_multicast_ifp = ifp; 918 im6o.im6o_multicast_hlim = 255; 919 im6o.im6o_multicast_loop = 0; 920 } 921 922 icmp6len = sizeof(*nd_na); 923 m->m_pkthdr.len = m->m_len = sizeof(struct ip6_hdr) + icmp6len; 924 m->m_data += max_linkhdr; /* or MH_ALIGN() equivalent? */ 925 926 /* fill neighbor advertisement packet */ 927 ip6 = mtod(m, struct ip6_hdr *); 928 ip6->ip6_flow = 0; 929 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 930 ip6->ip6_vfc |= IPV6_VERSION; 931 ip6->ip6_nxt = IPPROTO_ICMPV6; 932 ip6->ip6_hlim = 255; 933 if (IN6_IS_ADDR_UNSPECIFIED(&daddr6)) { 934 /* reply to DAD */ 935 daddr6.s6_addr16[0] = IPV6_ADDR_INT16_MLL; 936 daddr6.s6_addr16[1] = 0; 937 daddr6.s6_addr32[1] = 0; 938 daddr6.s6_addr32[2] = 0; 939 daddr6.s6_addr32[3] = IPV6_ADDR_INT32_ONE; 940 if (in6_setscope(&daddr6, ifp, NULL)) 941 goto bad; 942 943 flags &= ~ND_NA_FLAG_SOLICITED; 944 } 945 ip6->ip6_dst = daddr6; 946 bzero(&dst_sa, sizeof(struct sockaddr_in6)); 947 dst_sa.sin6_family = AF_INET6; 948 dst_sa.sin6_len = sizeof(struct sockaddr_in6); 949 dst_sa.sin6_addr = daddr6; 950 951 /* 952 * Select a source whose scope is the same as that of the dest. 953 */ 954 bcopy(&dst_sa, &ro.ro_dst, sizeof(dst_sa)); 955 src = in6_selectsrc(&dst_sa, NULL, NULL, &ro, NULL, NULL, &error); 956 if (src == NULL) { 957 char ip6buf[INET6_ADDRSTRLEN]; 958 nd6log((LOG_DEBUG, "nd6_na_output: source can't be " 959 "determined: dst=%s, error=%d\n", 960 ip6_sprintf(ip6buf, &dst_sa.sin6_addr), error)); 961 goto bad; 962 } 963 ip6->ip6_src = *src; 964 nd_na = (struct nd_neighbor_advert *)(ip6 + 1); 965 nd_na->nd_na_type = ND_NEIGHBOR_ADVERT; 966 nd_na->nd_na_code = 0; 967 nd_na->nd_na_target = *taddr6; 968 in6_clearscope(&nd_na->nd_na_target); /* XXX */ 969 970 /* 971 * "tlladdr" indicates NS's condition for adding tlladdr or not. 972 * see nd6_ns_input() for details. 973 * Basically, if NS packet is sent to unicast/anycast addr, 974 * target lladdr option SHOULD NOT be included. 975 */ 976 if (tlladdr) { 977 /* 978 * sdl0 != NULL indicates proxy NA. If we do proxy, use 979 * lladdr in sdl0. If we are not proxying (sending NA for 980 * my address) use lladdr configured for the interface. 981 */ 982 if (sdl0 == NULL) { 983 #ifdef DEV_CARP 984 if (ifp->if_carp) 985 mac = carp_macmatch6(ifp->if_carp, m, taddr6); 986 if (mac == NULL) 987 mac = nd6_ifptomac(ifp); 988 #else 989 mac = nd6_ifptomac(ifp); 990 #endif 991 } else if (sdl0->sa_family == AF_LINK) { 992 struct sockaddr_dl *sdl; 993 sdl = (struct sockaddr_dl *)sdl0; 994 if (sdl->sdl_alen == ifp->if_addrlen) 995 mac = LLADDR(sdl); 996 } 997 } 998 if (tlladdr && mac) { 999 int optlen = sizeof(struct nd_opt_hdr) + ifp->if_addrlen; 1000 struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)(nd_na + 1); 1001 1002 /* roundup to 8 bytes alignment! */ 1003 optlen = (optlen + 7) & ~7; 1004 1005 m->m_pkthdr.len += optlen; 1006 m->m_len += optlen; 1007 icmp6len += optlen; 1008 bzero((caddr_t)nd_opt, optlen); 1009 nd_opt->nd_opt_type = ND_OPT_TARGET_LINKADDR; 1010 nd_opt->nd_opt_len = optlen >> 3; 1011 bcopy(mac, (caddr_t)(nd_opt + 1), ifp->if_addrlen); 1012 } else 1013 flags &= ~ND_NA_FLAG_OVERRIDE; 1014 1015 ip6->ip6_plen = htons((u_short)icmp6len); 1016 nd_na->nd_na_flags_reserved = flags; 1017 nd_na->nd_na_cksum = 0; 1018 nd_na->nd_na_cksum = 1019 in6_cksum(m, IPPROTO_ICMPV6, sizeof(struct ip6_hdr), icmp6len); 1020 1021 ip6_output(m, NULL, &ro, 0, &im6o, NULL, NULL); 1022 icmp6_ifstat_inc(ifp, ifs6_out_msg); 1023 icmp6_ifstat_inc(ifp, ifs6_out_neighboradvert); 1024 icmp6stat.icp6s_outhist[ND_NEIGHBOR_ADVERT]++; 1025 1026 if (ro.ro_rt) { /* we don't cache this route. */ 1027 RTFREE(ro.ro_rt); 1028 } 1029 return; 1030 1031 bad: 1032 if (ro.ro_rt) { 1033 RTFREE(ro.ro_rt); 1034 } 1035 m_freem(m); 1036 return; 1037 } 1038 1039 caddr_t 1040 nd6_ifptomac(struct ifnet *ifp) 1041 { 1042 switch (ifp->if_type) { 1043 case IFT_ARCNET: 1044 case IFT_ETHER: 1045 case IFT_FDDI: 1046 case IFT_IEEE1394: 1047 #ifdef IFT_L2VLAN 1048 case IFT_L2VLAN: 1049 #endif 1050 #ifdef IFT_IEEE80211 1051 case IFT_IEEE80211: 1052 #endif 1053 #ifdef IFT_CARP 1054 case IFT_CARP: 1055 #endif 1056 case IFT_BRIDGE: 1057 case IFT_ISO88025: 1058 return IF_LLADDR(ifp); 1059 default: 1060 return NULL; 1061 } 1062 } 1063 1064 TAILQ_HEAD(dadq_head, dadq); 1065 struct dadq { 1066 TAILQ_ENTRY(dadq) dad_list; 1067 struct ifaddr *dad_ifa; 1068 int dad_count; /* max NS to send */ 1069 int dad_ns_tcount; /* # of trials to send NS */ 1070 int dad_ns_ocount; /* NS sent so far */ 1071 int dad_ns_icount; 1072 int dad_na_icount; 1073 struct callout dad_timer_ch; 1074 }; 1075 1076 static struct dadq_head dadq; 1077 static int dad_init = 0; 1078 1079 static struct dadq * 1080 nd6_dad_find(struct ifaddr *ifa) 1081 { 1082 struct dadq *dp; 1083 1084 for (dp = dadq.tqh_first; dp; dp = dp->dad_list.tqe_next) { 1085 if (dp->dad_ifa == ifa) 1086 return dp; 1087 } 1088 return NULL; 1089 } 1090 1091 static void 1092 nd6_dad_starttimer(struct dadq *dp, int ticks) 1093 { 1094 1095 callout_reset(&dp->dad_timer_ch, ticks, 1096 (void (*)(void *))nd6_dad_timer, (void *)dp->dad_ifa); 1097 } 1098 1099 static void 1100 nd6_dad_stoptimer(struct dadq *dp) 1101 { 1102 1103 callout_stop(&dp->dad_timer_ch); 1104 } 1105 1106 /* 1107 * Start Duplicate Address Detection (DAD) for specified interface address. 1108 */ 1109 void 1110 nd6_dad_start(struct ifaddr *ifa, int delay) 1111 { 1112 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1113 struct dadq *dp; 1114 char ip6buf[INET6_ADDRSTRLEN]; 1115 1116 if (!dad_init) { 1117 TAILQ_INIT(&dadq); 1118 dad_init++; 1119 } 1120 1121 /* 1122 * If we don't need DAD, don't do it. 1123 * There are several cases: 1124 * - DAD is disabled (ip6_dad_count == 0) 1125 * - the interface address is anycast 1126 */ 1127 if (!(ia->ia6_flags & IN6_IFF_TENTATIVE)) { 1128 log(LOG_DEBUG, 1129 "nd6_dad_start: called with non-tentative address " 1130 "%s(%s)\n", 1131 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr), 1132 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1133 return; 1134 } 1135 if (ia->ia6_flags & IN6_IFF_ANYCAST) { 1136 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1137 return; 1138 } 1139 if (!ip6_dad_count) { 1140 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1141 return; 1142 } 1143 if (ifa->ifa_ifp == NULL) 1144 panic("nd6_dad_start: ifa->ifa_ifp == NULL"); 1145 if (!(ifa->ifa_ifp->if_flags & IFF_UP)) { 1146 return; 1147 } 1148 if (nd6_dad_find(ifa) != NULL) { 1149 /* DAD already in progress */ 1150 return; 1151 } 1152 1153 dp = malloc(sizeof(*dp), M_IP6NDP, M_NOWAIT); 1154 if (dp == NULL) { 1155 log(LOG_ERR, "nd6_dad_start: memory allocation failed for " 1156 "%s(%s)\n", 1157 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr), 1158 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1159 return; 1160 } 1161 bzero(dp, sizeof(*dp)); 1162 callout_init(&dp->dad_timer_ch, 0); 1163 TAILQ_INSERT_TAIL(&dadq, (struct dadq *)dp, dad_list); 1164 1165 nd6log((LOG_DEBUG, "%s: starting DAD for %s\n", if_name(ifa->ifa_ifp), 1166 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr))); 1167 1168 /* 1169 * Send NS packet for DAD, ip6_dad_count times. 1170 * Note that we must delay the first transmission, if this is the 1171 * first packet to be sent from the interface after interface 1172 * (re)initialization. 1173 */ 1174 dp->dad_ifa = ifa; 1175 IFAREF(ifa); /* just for safety */ 1176 dp->dad_count = ip6_dad_count; 1177 dp->dad_ns_icount = dp->dad_na_icount = 0; 1178 dp->dad_ns_ocount = dp->dad_ns_tcount = 0; 1179 if (delay == 0) { 1180 nd6_dad_ns_output(dp, ifa); 1181 nd6_dad_starttimer(dp, 1182 (long)ND_IFINFO(ifa->ifa_ifp)->retrans * hz / 1000); 1183 } else { 1184 nd6_dad_starttimer(dp, delay); 1185 } 1186 } 1187 1188 /* 1189 * terminate DAD unconditionally. used for address removals. 1190 */ 1191 void 1192 nd6_dad_stop(struct ifaddr *ifa) 1193 { 1194 struct dadq *dp; 1195 1196 if (!dad_init) 1197 return; 1198 dp = nd6_dad_find(ifa); 1199 if (!dp) { 1200 /* DAD wasn't started yet */ 1201 return; 1202 } 1203 1204 nd6_dad_stoptimer(dp); 1205 1206 TAILQ_REMOVE(&dadq, (struct dadq *)dp, dad_list); 1207 free(dp, M_IP6NDP); 1208 dp = NULL; 1209 IFAFREE(ifa); 1210 } 1211 1212 static void 1213 nd6_dad_timer(struct ifaddr *ifa) 1214 { 1215 int s; 1216 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1217 struct dadq *dp; 1218 char ip6buf[INET6_ADDRSTRLEN]; 1219 1220 s = splnet(); /* XXX */ 1221 1222 /* Sanity check */ 1223 if (ia == NULL) { 1224 log(LOG_ERR, "nd6_dad_timer: called with null parameter\n"); 1225 goto done; 1226 } 1227 dp = nd6_dad_find(ifa); 1228 if (dp == NULL) { 1229 log(LOG_ERR, "nd6_dad_timer: DAD structure not found\n"); 1230 goto done; 1231 } 1232 if (ia->ia6_flags & IN6_IFF_DUPLICATED) { 1233 log(LOG_ERR, "nd6_dad_timer: called with duplicated address " 1234 "%s(%s)\n", 1235 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr), 1236 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1237 goto done; 1238 } 1239 if ((ia->ia6_flags & IN6_IFF_TENTATIVE) == 0) { 1240 log(LOG_ERR, "nd6_dad_timer: called with non-tentative address " 1241 "%s(%s)\n", 1242 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr), 1243 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1244 goto done; 1245 } 1246 1247 /* timeouted with IFF_{RUNNING,UP} check */ 1248 if (dp->dad_ns_tcount > dad_maxtry) { 1249 nd6log((LOG_INFO, "%s: could not run DAD, driver problem?\n", 1250 if_name(ifa->ifa_ifp))); 1251 1252 TAILQ_REMOVE(&dadq, (struct dadq *)dp, dad_list); 1253 free(dp, M_IP6NDP); 1254 dp = NULL; 1255 IFAFREE(ifa); 1256 goto done; 1257 } 1258 1259 /* Need more checks? */ 1260 if (dp->dad_ns_ocount < dp->dad_count) { 1261 /* 1262 * We have more NS to go. Send NS packet for DAD. 1263 */ 1264 nd6_dad_ns_output(dp, ifa); 1265 nd6_dad_starttimer(dp, 1266 (long)ND_IFINFO(ifa->ifa_ifp)->retrans * hz / 1000); 1267 } else { 1268 /* 1269 * We have transmitted sufficient number of DAD packets. 1270 * See what we've got. 1271 */ 1272 int duplicate; 1273 1274 duplicate = 0; 1275 1276 if (dp->dad_na_icount) { 1277 /* 1278 * the check is in nd6_dad_na_input(), 1279 * but just in case 1280 */ 1281 duplicate++; 1282 } 1283 1284 if (dp->dad_ns_icount) { 1285 /* We've seen NS, means DAD has failed. */ 1286 duplicate++; 1287 } 1288 1289 if (duplicate) { 1290 /* (*dp) will be freed in nd6_dad_duplicated() */ 1291 dp = NULL; 1292 nd6_dad_duplicated(ifa); 1293 } else { 1294 /* 1295 * We are done with DAD. No NA came, no NS came. 1296 * No duplicate address found. 1297 */ 1298 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1299 1300 nd6log((LOG_DEBUG, 1301 "%s: DAD complete for %s - no duplicates found\n", 1302 if_name(ifa->ifa_ifp), 1303 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr))); 1304 1305 TAILQ_REMOVE(&dadq, (struct dadq *)dp, dad_list); 1306 free(dp, M_IP6NDP); 1307 dp = NULL; 1308 IFAFREE(ifa); 1309 } 1310 } 1311 1312 done: 1313 splx(s); 1314 } 1315 1316 void 1317 nd6_dad_duplicated(struct ifaddr *ifa) 1318 { 1319 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1320 struct ifnet *ifp; 1321 struct dadq *dp; 1322 char ip6buf[INET6_ADDRSTRLEN]; 1323 1324 dp = nd6_dad_find(ifa); 1325 if (dp == NULL) { 1326 log(LOG_ERR, "nd6_dad_duplicated: DAD structure not found\n"); 1327 return; 1328 } 1329 1330 log(LOG_ERR, "%s: DAD detected duplicate IPv6 address %s: " 1331 "NS in/out=%d/%d, NA in=%d\n", 1332 if_name(ifa->ifa_ifp), ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr), 1333 dp->dad_ns_icount, dp->dad_ns_ocount, dp->dad_na_icount); 1334 1335 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1336 ia->ia6_flags |= IN6_IFF_DUPLICATED; 1337 1338 /* We are done with DAD, with duplicate address found. (failure) */ 1339 nd6_dad_stoptimer(dp); 1340 1341 ifp = ifa->ifa_ifp; 1342 log(LOG_ERR, "%s: DAD complete for %s - duplicate found\n", 1343 if_name(ifp), ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr)); 1344 log(LOG_ERR, "%s: manual intervention required\n", 1345 if_name(ifp)); 1346 1347 /* 1348 * If the address is a link-local address formed from an interface 1349 * identifier based on the hardware address which is supposed to be 1350 * uniquely assigned (e.g., EUI-64 for an Ethernet interface), IP 1351 * operation on the interface SHOULD be disabled. 1352 * [rfc2462bis-03 Section 5.4.5] 1353 */ 1354 if (IN6_IS_ADDR_LINKLOCAL(&ia->ia_addr.sin6_addr)) { 1355 struct in6_addr in6; 1356 1357 /* 1358 * To avoid over-reaction, we only apply this logic when we are 1359 * very sure that hardware addresses are supposed to be unique. 1360 */ 1361 switch (ifp->if_type) { 1362 case IFT_ETHER: 1363 case IFT_FDDI: 1364 case IFT_ATM: 1365 case IFT_IEEE1394: 1366 #ifdef IFT_IEEE80211 1367 case IFT_IEEE80211: 1368 #endif 1369 in6 = ia->ia_addr.sin6_addr; 1370 if (in6_get_hw_ifid(ifp, &in6) == 0 && 1371 IN6_ARE_ADDR_EQUAL(&ia->ia_addr.sin6_addr, &in6)) { 1372 ND_IFINFO(ifp)->flags |= ND6_IFF_IFDISABLED; 1373 log(LOG_ERR, "%s: possible hardware address " 1374 "duplication detected, disable IPv6\n", 1375 if_name(ifp)); 1376 } 1377 break; 1378 } 1379 } 1380 1381 TAILQ_REMOVE(&dadq, (struct dadq *)dp, dad_list); 1382 free(dp, M_IP6NDP); 1383 dp = NULL; 1384 IFAFREE(ifa); 1385 } 1386 1387 static void 1388 nd6_dad_ns_output(struct dadq *dp, struct ifaddr *ifa) 1389 { 1390 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1391 struct ifnet *ifp = ifa->ifa_ifp; 1392 1393 dp->dad_ns_tcount++; 1394 if ((ifp->if_flags & IFF_UP) == 0) { 1395 return; 1396 } 1397 if ((ifp->if_drv_flags & IFF_DRV_RUNNING) == 0) { 1398 return; 1399 } 1400 1401 dp->dad_ns_ocount++; 1402 nd6_ns_output(ifp, NULL, &ia->ia_addr.sin6_addr, NULL, 1); 1403 } 1404 1405 static void 1406 nd6_dad_ns_input(struct ifaddr *ifa) 1407 { 1408 struct in6_ifaddr *ia; 1409 struct ifnet *ifp; 1410 const struct in6_addr *taddr6; 1411 struct dadq *dp; 1412 int duplicate; 1413 1414 if (ifa == NULL) 1415 panic("ifa == NULL in nd6_dad_ns_input"); 1416 1417 ia = (struct in6_ifaddr *)ifa; 1418 ifp = ifa->ifa_ifp; 1419 taddr6 = &ia->ia_addr.sin6_addr; 1420 duplicate = 0; 1421 dp = nd6_dad_find(ifa); 1422 1423 /* Quickhack - completely ignore DAD NS packets */ 1424 if (dad_ignore_ns) { 1425 char ip6buf[INET6_ADDRSTRLEN]; 1426 nd6log((LOG_INFO, 1427 "nd6_dad_ns_input: ignoring DAD NS packet for " 1428 "address %s(%s)\n", ip6_sprintf(ip6buf, taddr6), 1429 if_name(ifa->ifa_ifp))); 1430 return; 1431 } 1432 1433 /* 1434 * if I'm yet to start DAD, someone else started using this address 1435 * first. I have a duplicate and you win. 1436 */ 1437 if (dp == NULL || dp->dad_ns_ocount == 0) 1438 duplicate++; 1439 1440 /* XXX more checks for loopback situation - see nd6_dad_timer too */ 1441 1442 if (duplicate) { 1443 dp = NULL; /* will be freed in nd6_dad_duplicated() */ 1444 nd6_dad_duplicated(ifa); 1445 } else { 1446 /* 1447 * not sure if I got a duplicate. 1448 * increment ns count and see what happens. 1449 */ 1450 if (dp) 1451 dp->dad_ns_icount++; 1452 } 1453 } 1454 1455 static void 1456 nd6_dad_na_input(struct ifaddr *ifa) 1457 { 1458 struct dadq *dp; 1459 1460 if (ifa == NULL) 1461 panic("ifa == NULL in nd6_dad_na_input"); 1462 1463 dp = nd6_dad_find(ifa); 1464 if (dp) 1465 dp->dad_na_icount++; 1466 1467 /* remove the address. */ 1468 nd6_dad_duplicated(ifa); 1469 } 1470