1 /* $NetBSD: nd6_nbr.c,v 1.133 2016/12/14 04:05:11 ozaki-r Exp $ */ 2 /* $KAME: nd6_nbr.c,v 1.61 2001/02/10 16:06:14 jinmei Exp $ */ 3 4 /* 5 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project. 6 * All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. Neither the name of the project nor the names of its contributors 17 * may be used to endorse or promote products derived from this software 18 * without specific prior written permission. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND 21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE 24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30 * SUCH DAMAGE. 31 */ 32 33 #include <sys/cdefs.h> 34 __KERNEL_RCSID(0, "$NetBSD: nd6_nbr.c,v 1.133 2016/12/14 04:05:11 ozaki-r Exp $"); 35 36 #ifdef _KERNEL_OPT 37 #include "opt_inet.h" 38 #include "opt_net_mpsafe.h" 39 #endif 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/socketvar.h> 47 #include <sys/sockio.h> 48 #include <sys/time.h> 49 #include <sys/kernel.h> 50 #include <sys/errno.h> 51 #include <sys/ioctl.h> 52 #include <sys/syslog.h> 53 #include <sys/queue.h> 54 #include <sys/callout.h> 55 56 #include <net/if.h> 57 #include <net/if_types.h> 58 #include <net/if_dl.h> 59 #include <net/route.h> 60 61 #include <netinet/in.h> 62 #include <netinet/in_var.h> 63 #include <netinet6/in6_var.h> 64 #include <netinet6/in6_ifattach.h> 65 #include <netinet/ip6.h> 66 #include <netinet6/ip6_var.h> 67 #include <netinet6/scope6_var.h> 68 #include <netinet6/nd6.h> 69 #include <netinet/icmp6.h> 70 #include <netinet6/icmp6_private.h> 71 72 #include "carp.h" 73 #if NCARP > 0 74 #include <netinet/ip_carp.h> 75 #endif 76 77 #include <net/net_osdep.h> 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 static void nd6_dad_duplicated(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; 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 router = ip6_forwarding; 113 int tlladdr; 114 union nd_opts ndopts; 115 const struct sockaddr_dl *proxydl = NULL; 116 struct psref psref; 117 struct psref psref_ia; 118 119 ifp = m_get_rcvif_psref(m, &psref); 120 if (ifp == NULL) 121 goto freeit; 122 123 IP6_EXTHDR_GET(nd_ns, struct nd_neighbor_solicit *, m, off, icmp6len); 124 if (nd_ns == NULL) { 125 ICMP6_STATINC(ICMP6_STAT_TOOSHORT); 126 m_put_rcvif_psref(ifp, &psref); 127 return; 128 } 129 ip6 = mtod(m, struct ip6_hdr *); /* adjust pointer for safety */ 130 taddr6 = nd_ns->nd_ns_target; 131 if (in6_setscope(&taddr6, ifp, NULL) != 0) 132 goto bad; 133 134 if (ip6->ip6_hlim != 255) { 135 nd6log(LOG_ERR, "invalid hlim (%d) from %s to %s on %s\n", 136 ip6->ip6_hlim, ip6_sprintf(&ip6->ip6_src), 137 ip6_sprintf(&ip6->ip6_dst), if_name(ifp)); 138 goto bad; 139 } 140 141 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) { 142 /* dst has to be a solicited node multicast address. */ 143 /* don't check ifindex portion */ 144 if (daddr6.s6_addr16[0] == IPV6_ADDR_INT16_MLL && 145 daddr6.s6_addr32[1] == 0 && 146 daddr6.s6_addr32[2] == IPV6_ADDR_INT32_ONE && 147 daddr6.s6_addr8[12] == 0xff) { 148 ; /* good */ 149 } else { 150 nd6log(LOG_INFO, "bad DAD packet (wrong ip6 dst)\n"); 151 goto bad; 152 } 153 } else { 154 struct sockaddr_in6 ssin6; 155 156 /* 157 * Make sure the source address is from a neighbor's address. 158 */ 159 sockaddr_in6_init(&ssin6, &saddr6, 0, 0, 0); 160 if (nd6_is_addr_neighbor(&ssin6, ifp) == 0) { 161 nd6log(LOG_INFO, 162 "NS packet from non-neighbor %s on %s\n", 163 ip6_sprintf(&saddr6), if_name(ifp)); 164 goto bad; 165 } 166 } 167 168 169 if (IN6_IS_ADDR_MULTICAST(&taddr6)) { 170 nd6log(LOG_INFO, "bad NS target (multicast)\n"); 171 goto bad; 172 } 173 174 icmp6len -= sizeof(*nd_ns); 175 nd6_option_init(nd_ns + 1, icmp6len, &ndopts); 176 if (nd6_options(&ndopts) < 0) { 177 nd6log(LOG_INFO, "invalid ND option, ignored\n"); 178 /* nd6_options have incremented stats */ 179 goto freeit; 180 } 181 182 if (ndopts.nd_opts_src_lladdr) { 183 lladdr = (char *)(ndopts.nd_opts_src_lladdr + 1); 184 lladdrlen = ndopts.nd_opts_src_lladdr->nd_opt_len << 3; 185 } 186 187 if (IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_src) && lladdr) { 188 nd6log(LOG_INFO, 189 "bad DAD packet (link-layer address option)\n"); 190 goto bad; 191 } 192 193 /* 194 * Attaching target link-layer address to the NA? 195 * (RFC 2461 7.2.4) 196 * 197 * NS IP dst is multicast MUST add 198 * Otherwise MAY be omitted 199 * 200 * In this implementation, we omit the target link-layer address 201 * in the "MAY" case. 202 */ 203 #if 0 /* too much! */ 204 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &daddr6); 205 if (ifa && (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_ANYCAST)) 206 tlladdr = 0; 207 else 208 #endif 209 if (!IN6_IS_ADDR_MULTICAST(&daddr6)) 210 tlladdr = 0; 211 else 212 tlladdr = 1; 213 214 /* 215 * Target address (taddr6) must be either: 216 * (1) Valid unicast/anycast address for my receiving interface, 217 * (2) Unicast address for which I'm offering proxy service, or 218 * (3) "tentative" address on which DAD is being performed. 219 */ 220 /* (1) and (3) check. */ 221 #if NCARP > 0 222 if (ifp->if_carp && ifp->if_type != IFT_CARP) { 223 int s = pserialize_read_enter(); 224 ifa = carp_iamatch6(ifp->if_carp, &taddr6); 225 if (ifa != NULL) 226 ifa_acquire(ifa, &psref_ia); 227 pserialize_read_exit(s); 228 } else 229 ifa = NULL; 230 if (!ifa) 231 ifa = (struct ifaddr *)in6ifa_ifpwithaddr_psref(ifp, &taddr6, 232 &psref_ia); 233 #else 234 ifa = (struct ifaddr *)in6ifa_ifpwithaddr_psref(ifp, &taddr6, 235 &psref_ia); 236 #endif 237 238 /* (2) check. */ 239 if (ifa == NULL) { 240 struct rtentry *rt; 241 struct sockaddr_in6 tsin6; 242 243 sockaddr_in6_init(&tsin6, &taddr6, 0, 0, 0); 244 245 rt = rtalloc1(sin6tosa(&tsin6), 0); 246 if (rt && (rt->rt_flags & RTF_ANNOUNCE) != 0 && 247 rt->rt_gateway->sa_family == AF_LINK) { 248 /* 249 * proxy NDP for single entry 250 */ 251 ifa = (struct ifaddr *)in6ifa_ifpforlinklocal_psref(ifp, 252 IN6_IFF_NOTREADY|IN6_IFF_ANYCAST, &psref_ia); 253 if (ifa) { 254 proxy = 1; 255 proxydl = satocsdl(rt->rt_gateway); 256 router = 0; /* XXX */ 257 } 258 } 259 if (rt) 260 rt_unref(rt); 261 } 262 if (ifa == NULL) { 263 /* 264 * We've got an NS packet, and we don't have that address 265 * assigned for us. We MUST silently ignore it. 266 * See RFC2461 7.2.3. 267 */ 268 goto freeit; 269 } 270 myaddr6 = *IFA_IN6(ifa); 271 anycast = ((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_ANYCAST; 272 tentative = ((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_TENTATIVE; 273 if (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_DUPLICATED) 274 goto freeit; 275 276 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) { 277 nd6log(LOG_INFO, "lladdrlen mismatch for %s " 278 "(if %d, NS packet %d)\n", 279 ip6_sprintf(&taddr6), ifp->if_addrlen, lladdrlen - 2); 280 goto bad; 281 } 282 283 if (IN6_ARE_ADDR_EQUAL(&myaddr6, &saddr6)) { 284 nd6log(LOG_INFO, "duplicate IP6 address %s\n", 285 ip6_sprintf(&saddr6)); 286 goto freeit; 287 } 288 289 /* 290 * We have neighbor solicitation packet, with target address equals to 291 * one of my tentative address. 292 * 293 * src addr how to process? 294 * --- --- 295 * multicast of course, invalid (rejected in ip6_input) 296 * unicast somebody is doing address resolution -> ignore 297 * unspec dup address detection 298 * 299 * The processing is defined in RFC 2462. 300 */ 301 if (tentative) { 302 /* 303 * If source address is unspecified address, it is for 304 * duplicate address detection. 305 * 306 * If not, the packet is for addess resolution; 307 * silently ignore it. 308 */ 309 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) 310 nd6_dad_ns_input(ifa); 311 ifa_release(ifa, &psref_ia); 312 ifa = NULL; 313 314 goto freeit; 315 } 316 ifa_release(ifa, &psref_ia); 317 ifa = NULL; 318 319 /* 320 * If the source address is unspecified address, entries must not 321 * be created or updated. 322 * It looks that sender is performing DAD. Output NA toward 323 * all-node multicast address, to tell the sender that I'm using 324 * the address. 325 * S bit ("solicited") must be zero. 326 */ 327 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) { 328 struct in6_addr in6_all; 329 330 in6_all = in6addr_linklocal_allnodes; 331 if (in6_setscope(&in6_all, ifp, NULL) != 0) 332 goto bad; 333 nd6_na_output(ifp, &in6_all, &taddr6, 334 ((anycast || proxy || !tlladdr) ? 0 : ND_NA_FLAG_OVERRIDE) | 335 (ip6_forwarding ? ND_NA_FLAG_ROUTER : 0), 336 tlladdr, (const struct sockaddr *)proxydl); 337 goto freeit; 338 } 339 340 nd6_cache_lladdr(ifp, &saddr6, lladdr, lladdrlen, ND_NEIGHBOR_SOLICIT, 0); 341 342 nd6_na_output(ifp, &saddr6, &taddr6, 343 ((anycast || proxy || !tlladdr) ? 0 : ND_NA_FLAG_OVERRIDE) | 344 (router ? ND_NA_FLAG_ROUTER : 0) | ND_NA_FLAG_SOLICITED, 345 tlladdr, (const struct sockaddr *)proxydl); 346 freeit: 347 ifa_release(ifa, &psref_ia); 348 m_put_rcvif_psref(ifp, &psref); 349 m_freem(m); 350 return; 351 352 bad: 353 nd6log(LOG_ERR, "src=%s\n", ip6_sprintf(&saddr6)); 354 nd6log(LOG_ERR, "dst=%s\n", ip6_sprintf(&daddr6)); 355 nd6log(LOG_ERR, "tgt=%s\n", ip6_sprintf(&taddr6)); 356 ICMP6_STATINC(ICMP6_STAT_BADNS); 357 ifa_release(ifa, &psref_ia); 358 m_put_rcvif_psref(ifp, &psref); 359 m_freem(m); 360 } 361 362 /* 363 * Output a Neighbor Solicitation Message. Caller specifies: 364 * - ICMP6 header source IP6 address 365 * - ND6 header target IP6 address 366 * - ND6 header source datalink address 367 * 368 * Based on RFC 2461 369 * Based on RFC 2462 (duplicate address detection) 370 */ 371 void 372 nd6_ns_output(struct ifnet *ifp, const struct in6_addr *daddr6, 373 const struct in6_addr *taddr6, 374 struct in6_addr *hsrc, 375 int dad /* duplicate address detection */) 376 { 377 struct mbuf *m; 378 struct ip6_hdr *ip6; 379 struct nd_neighbor_solicit *nd_ns; 380 struct in6_addr *src, src_in; 381 struct ip6_moptions im6o; 382 int icmp6len; 383 int maxlen; 384 const void *mac; 385 struct route ro; 386 387 if (IN6_IS_ADDR_MULTICAST(taddr6)) 388 return; 389 390 memset(&ro, 0, sizeof(ro)); 391 392 /* estimate the size of message */ 393 maxlen = sizeof(*ip6) + sizeof(*nd_ns); 394 maxlen += (sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7; 395 #ifdef DIAGNOSTIC 396 if (max_linkhdr + maxlen >= MCLBYTES) { 397 printf("nd6_ns_output: max_linkhdr + maxlen >= MCLBYTES " 398 "(%d + %d > %d)\n", max_linkhdr, maxlen, MCLBYTES); 399 panic("nd6_ns_output: insufficient MCLBYTES"); 400 /* NOTREACHED */ 401 } 402 #endif 403 404 MGETHDR(m, M_DONTWAIT, MT_DATA); 405 if (m && max_linkhdr + maxlen >= MHLEN) { 406 MCLGET(m, M_DONTWAIT); 407 if ((m->m_flags & M_EXT) == 0) { 408 m_free(m); 409 m = NULL; 410 } 411 } 412 if (m == NULL) 413 return; 414 m_reset_rcvif(m); 415 416 if (daddr6 == NULL || IN6_IS_ADDR_MULTICAST(daddr6)) { 417 m->m_flags |= M_MCAST; 418 im6o.im6o_multicast_if_index = if_get_index(ifp); 419 im6o.im6o_multicast_hlim = 255; 420 im6o.im6o_multicast_loop = 0; 421 } 422 423 icmp6len = sizeof(*nd_ns); 424 m->m_pkthdr.len = m->m_len = sizeof(*ip6) + icmp6len; 425 m->m_data += max_linkhdr; /* or MH_ALIGN() equivalent? */ 426 427 /* fill neighbor solicitation packet */ 428 ip6 = mtod(m, struct ip6_hdr *); 429 ip6->ip6_flow = 0; 430 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 431 ip6->ip6_vfc |= IPV6_VERSION; 432 /* ip6->ip6_plen will be set later */ 433 ip6->ip6_nxt = IPPROTO_ICMPV6; 434 ip6->ip6_hlim = 255; 435 if (daddr6) 436 ip6->ip6_dst = *daddr6; 437 else { 438 ip6->ip6_dst.s6_addr16[0] = IPV6_ADDR_INT16_MLL; 439 ip6->ip6_dst.s6_addr16[1] = 0; 440 ip6->ip6_dst.s6_addr32[1] = 0; 441 ip6->ip6_dst.s6_addr32[2] = IPV6_ADDR_INT32_ONE; 442 ip6->ip6_dst.s6_addr32[3] = taddr6->s6_addr32[3]; 443 ip6->ip6_dst.s6_addr8[12] = 0xff; 444 if (in6_setscope(&ip6->ip6_dst, ifp, NULL) != 0) 445 goto bad; 446 } 447 if (!dad) { 448 int s; 449 /* 450 * RFC2461 7.2.2: 451 * "If the source address of the packet prompting the 452 * solicitation is the same as one of the addresses assigned 453 * to the outgoing interface, that address SHOULD be placed 454 * in the IP Source Address of the outgoing solicitation. 455 * Otherwise, any one of the addresses assigned to the 456 * interface should be used." 457 * 458 * We use the source address for the prompting packet 459 * (hsrc), if: 460 * - hsrc is given from the caller (by giving "ln"), and 461 * - hsrc belongs to the outgoing interface. 462 * Otherwise, we perform the source address selection as usual. 463 */ 464 s = pserialize_read_enter(); 465 if (hsrc && in6ifa_ifpwithaddr(ifp, hsrc)) 466 src = hsrc; 467 else { 468 int error; 469 struct sockaddr_in6 dst_sa; 470 471 sockaddr_in6_init(&dst_sa, &ip6->ip6_dst, 0, 0, 0); 472 473 error = in6_selectsrc(&dst_sa, NULL, 474 NULL, &ro, NULL, NULL, NULL, &src_in); 475 if (error != 0) { 476 nd6log(LOG_DEBUG, "source can't be " 477 "determined: dst=%s, error=%d\n", 478 ip6_sprintf(&dst_sa.sin6_addr), error); 479 pserialize_read_exit(s); 480 goto bad; 481 } 482 src = &src_in; 483 } 484 pserialize_read_exit(s); 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 memset(&src_in, 0, 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 memset((void *)nd_opt, 0, optlen); 526 nd_opt->nd_opt_type = ND_OPT_SOURCE_LINKADDR; 527 nd_opt->nd_opt_len = optlen >> 3; 528 memcpy((void *)(nd_opt + 1), mac, ifp->if_addrlen); 529 } 530 531 ip6->ip6_plen = htons((u_int16_t)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 ICMP6_STATINC(ICMP6_STAT_OUTHIST + ND_NEIGHBOR_SOLICIT); 540 541 rtcache_free(&ro); 542 return; 543 544 bad: 545 rtcache_free(&ro); 546 m_freem(m); 547 return; 548 } 549 550 /* 551 * Neighbor advertisement input handling. 552 * 553 * Based on RFC 2461 554 * Based on RFC 2462 (duplicate address detection) 555 * 556 * the following items are not implemented yet: 557 * - proxy advertisement delay rule (RFC2461 7.2.8, last paragraph, SHOULD) 558 * - anycast advertisement delay rule (RFC2461 7.2.7, SHOULD) 559 */ 560 void 561 nd6_na_input(struct mbuf *m, int off, int icmp6len) 562 { 563 struct ifnet *ifp; 564 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 565 struct nd_neighbor_advert *nd_na; 566 struct in6_addr saddr6 = ip6->ip6_src; 567 struct in6_addr daddr6 = ip6->ip6_dst; 568 struct in6_addr taddr6; 569 int flags; 570 int is_router; 571 int is_solicited; 572 int is_override; 573 char *lladdr = NULL; 574 int lladdrlen = 0; 575 struct ifaddr *ifa; 576 struct llentry *ln = NULL; 577 union nd_opts ndopts; 578 struct sockaddr_in6 ssin6; 579 int rt_announce; 580 bool checklink = false; 581 struct psref psref; 582 struct psref psref_ia; 583 584 ifp = m_get_rcvif_psref(m, &psref); 585 if (ifp == NULL) 586 goto freeit; 587 588 if (ip6->ip6_hlim != 255) { 589 nd6log(LOG_ERR, 590 "invalid hlim (%d) from %s to %s on %s\n", 591 ip6->ip6_hlim, ip6_sprintf(&ip6->ip6_src), 592 ip6_sprintf(&ip6->ip6_dst), if_name(ifp)); 593 goto bad; 594 } 595 596 IP6_EXTHDR_GET(nd_na, struct nd_neighbor_advert *, m, off, icmp6len); 597 if (nd_na == NULL) { 598 m_put_rcvif_psref(ifp, &psref); 599 ICMP6_STATINC(ICMP6_STAT_TOOSHORT); 600 return; 601 } 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 m_put_rcvif_psref(ifp, &psref); 611 return; /* XXX: impossible */ 612 } 613 614 if (IN6_IS_ADDR_MULTICAST(&taddr6)) { 615 nd6log(LOG_ERR, "invalid target address %s\n", 616 ip6_sprintf(&taddr6)); 617 goto bad; 618 } 619 if (is_solicited && IN6_IS_ADDR_MULTICAST(&daddr6)) { 620 nd6log(LOG_ERR, "a solicited adv is multicasted\n"); 621 goto bad; 622 } 623 624 icmp6len -= sizeof(*nd_na); 625 nd6_option_init(nd_na + 1, icmp6len, &ndopts); 626 if (nd6_options(&ndopts) < 0) { 627 nd6log(LOG_INFO, "invalid ND option, ignored\n"); 628 /* nd6_options have incremented stats */ 629 goto freeit; 630 } 631 632 if (ndopts.nd_opts_tgt_lladdr) { 633 lladdr = (char *)(ndopts.nd_opts_tgt_lladdr + 1); 634 lladdrlen = ndopts.nd_opts_tgt_lladdr->nd_opt_len << 3; 635 } 636 637 ifa = (struct ifaddr *)in6ifa_ifpwithaddr_psref(ifp, &taddr6, &psref_ia); 638 639 /* 640 * Target address matches one of my interface address. 641 * 642 * If my address is tentative, this means that there's somebody 643 * already using the same address as mine. This indicates DAD failure. 644 * This is defined in RFC 2462. 645 * 646 * Otherwise, process as defined in RFC 2461. 647 */ 648 if (ifa 649 && (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_TENTATIVE)) { 650 nd6_dad_na_input(ifa); 651 ifa_release(ifa, &psref_ia); 652 ifa = NULL; 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(&taddr6)); 661 ifa_release(ifa, &psref_ia); 662 ifa = NULL; 663 goto freeit; 664 } 665 666 /* 667 * Make sure the source address is from a neighbor's address. 668 */ 669 sockaddr_in6_init(&ssin6, &saddr6, 0, 0, 0); 670 if (nd6_is_addr_neighbor(&ssin6, ifp) == 0) { 671 nd6log(LOG_INFO, "ND packet from non-neighbor %s on %s\n", 672 ip6_sprintf(&saddr6), if_name(ifp)); 673 goto bad; 674 } 675 676 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) { 677 nd6log(LOG_INFO, "lladdrlen mismatch for %s " 678 "(if %d, NA packet %d)\n", ip6_sprintf(&taddr6), 679 ifp->if_addrlen, lladdrlen - 2); 680 goto bad; 681 } 682 683 /* 684 * If no neighbor cache entry is found, NA SHOULD silently be 685 * discarded. 686 */ 687 ln = nd6_lookup(&taddr6, ifp, true); 688 if (ln == NULL) 689 goto freeit; 690 691 rt_announce = 0; 692 if (ln->ln_state == ND6_LLINFO_INCOMPLETE) { 693 /* 694 * If the link-layer has address, and no lladdr option came, 695 * discard the packet. 696 */ 697 if (ifp->if_addrlen && !lladdr) 698 goto freeit; 699 700 /* 701 * Record link-layer address, and update the state. 702 */ 703 memcpy(&ln->ll_addr, lladdr, ifp->if_addrlen); 704 ln->la_flags |= LLE_VALID; 705 rt_announce = 1; 706 if (is_solicited) { 707 ln->ln_state = ND6_LLINFO_REACHABLE; 708 ln->ln_byhint = 0; 709 if (!ND6_LLINFO_PERMANENT(ln)) { 710 nd6_llinfo_settimer(ln, 711 ND_IFINFO(ln->lle_tbl->llt_ifp)->reachable * hz); 712 } 713 } else { 714 ln->ln_state = ND6_LLINFO_STALE; 715 nd6_llinfo_settimer(ln, nd6_gctimer * hz); 716 } 717 if ((ln->ln_router = is_router) != 0) { 718 /* 719 * This means a router's state has changed from 720 * non-reachable to probably reachable, and might 721 * affect the status of associated prefixes.. 722 */ 723 checklink = true; 724 } 725 } else { 726 int llchange; 727 728 /* 729 * Check if the link-layer address has changed or not. 730 */ 731 if (lladdr == NULL) 732 llchange = 0; 733 else { 734 if (ln->la_flags & LLE_VALID) { 735 if (memcmp(lladdr, &ln->ll_addr, ifp->if_addrlen)) 736 llchange = rt_announce = 1; 737 else 738 llchange = 0; 739 } else 740 llchange = rt_announce = 1; 741 } 742 743 /* 744 * This is VERY complex. Look at it with care. 745 * 746 * override solicit lladdr llchange action 747 * (L: record lladdr) 748 * 749 * 0 0 n -- (2c) 750 * 0 0 y n (2b) L 751 * 0 0 y y (1) REACHABLE->STALE 752 * 0 1 n -- (2c) *->REACHABLE 753 * 0 1 y n (2b) L *->REACHABLE 754 * 0 1 y y (1) REACHABLE->STALE 755 * 1 0 n -- (2a) 756 * 1 0 y n (2a) L 757 * 1 0 y y (2a) L *->STALE 758 * 1 1 n -- (2a) *->REACHABLE 759 * 1 1 y n (2a) L *->REACHABLE 760 * 1 1 y y (2a) L *->REACHABLE 761 */ 762 if (!is_override && lladdr != NULL && llchange) { /* (1) */ 763 /* 764 * If state is REACHABLE, make it STALE. 765 * no other updates should be done. 766 */ 767 if (ln->ln_state == ND6_LLINFO_REACHABLE) { 768 ln->ln_state = ND6_LLINFO_STALE; 769 nd6_llinfo_settimer(ln, nd6_gctimer * hz); 770 } 771 goto freeit; 772 } else if (is_override /* (2a) */ 773 || (!is_override && lladdr != NULL && !llchange) /* (2b) */ 774 || lladdr == NULL) { /* (2c) */ 775 /* 776 * Update link-local address, if any. 777 */ 778 if (lladdr != NULL) { 779 memcpy(&ln->ll_addr, lladdr, ifp->if_addrlen); 780 ln->la_flags |= LLE_VALID; 781 } 782 783 /* 784 * If solicited, make the state REACHABLE. 785 * If not solicited and the link-layer address was 786 * changed, make it STALE. 787 */ 788 if (is_solicited) { 789 ln->ln_state = ND6_LLINFO_REACHABLE; 790 ln->ln_byhint = 0; 791 if (!ND6_LLINFO_PERMANENT(ln)) { 792 nd6_llinfo_settimer(ln, 793 ND_IFINFO(ifp)->reachable * hz); 794 } 795 } else { 796 if (lladdr && llchange) { 797 ln->ln_state = ND6_LLINFO_STALE; 798 nd6_llinfo_settimer(ln, 799 nd6_gctimer * hz); 800 } 801 } 802 } 803 804 if (ln->ln_router && !is_router) { 805 /* 806 * The peer dropped the router flag. 807 * Remove the sender from the Default Router List and 808 * update the Destination Cache entries. 809 */ 810 struct nd_defrouter *dr; 811 const struct in6_addr *in6; 812 int s; 813 814 in6 = &ln->r_l3addr.addr6; 815 816 /* 817 * Lock to protect the default router list. 818 * XXX: this might be unnecessary, since this function 819 * is only called under the network software interrupt 820 * context. However, we keep it just for safety. 821 */ 822 s = splsoftnet(); 823 dr = nd6_defrouter_lookup(in6, ln->lle_tbl->llt_ifp); 824 if (dr) 825 nd6_defrtrlist_del(dr, NULL); 826 else if (!ip6_forwarding) { 827 /* 828 * Even if the neighbor is not in the default 829 * router list, the neighbor may be used 830 * as a next hop for some destinations 831 * (e.g. redirect case). So we must 832 * call nd6_rt_flush explicitly. 833 */ 834 nd6_rt_flush(&ip6->ip6_src, ln->lle_tbl->llt_ifp); 835 } 836 splx(s); 837 } 838 ln->ln_router = is_router; 839 } 840 /* 841 * XXX: does this matter? 842 * rt->rt_flags &= ~RTF_REJECT; 843 */ 844 ln->ln_asked = 0; 845 nd6_llinfo_release_pkts(ln, ifp); 846 /* FIXME */ 847 #if 0 848 if (rt_announce) /* tell user process about any new lladdr */ 849 rt_newmsg(RTM_CHANGE, rt); 850 #endif 851 852 freeit: 853 if (ln != NULL) 854 LLE_WUNLOCK(ln); 855 856 if (checklink) 857 nd6_pfxlist_onlink_check(); 858 859 m_put_rcvif_psref(ifp, &psref); 860 m_freem(m); 861 return; 862 863 bad: 864 if (ln != NULL) 865 LLE_WUNLOCK(ln); 866 867 ICMP6_STATINC(ICMP6_STAT_BADNA); 868 m_put_rcvif_psref(ifp, &psref); 869 m_freem(m); 870 } 871 872 /* 873 * Neighbor advertisement output handling. 874 * 875 * Based on RFC 2461 876 * 877 * the following items are not implemented yet: 878 * - proxy advertisement delay rule (RFC2461 7.2.8, last paragraph, SHOULD) 879 * - anycast advertisement delay rule (RFC2461 7.2.7, SHOULD) 880 */ 881 void 882 nd6_na_output( 883 struct ifnet *ifp, 884 const struct in6_addr *daddr6_0, 885 const struct in6_addr *taddr6, 886 u_long flags, 887 int tlladdr, /* 1 if include target link-layer address */ 888 const struct sockaddr *sdl0) /* sockaddr_dl (= proxy NA) or NULL */ 889 { 890 struct mbuf *m; 891 struct ip6_hdr *ip6; 892 struct nd_neighbor_advert *nd_na; 893 struct ip6_moptions im6o; 894 struct sockaddr *dst; 895 union { 896 struct sockaddr dst; 897 struct sockaddr_in6 dst6; 898 } u; 899 struct in6_addr daddr6; 900 int icmp6len, maxlen, error; 901 const void *mac; 902 struct route ro; 903 904 mac = NULL; 905 memset(&ro, 0, sizeof(ro)); 906 907 daddr6 = *daddr6_0; /* make a local copy for modification */ 908 909 /* estimate the size of message */ 910 maxlen = sizeof(*ip6) + sizeof(*nd_na); 911 maxlen += (sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7; 912 #ifdef DIAGNOSTIC 913 if (max_linkhdr + maxlen >= MCLBYTES) { 914 printf("nd6_na_output: max_linkhdr + maxlen >= MCLBYTES " 915 "(%d + %d > %d)\n", max_linkhdr, maxlen, MCLBYTES); 916 panic("nd6_na_output: insufficient MCLBYTES"); 917 /* NOTREACHED */ 918 } 919 #endif 920 921 MGETHDR(m, M_DONTWAIT, MT_DATA); 922 if (m && max_linkhdr + maxlen >= MHLEN) { 923 MCLGET(m, M_DONTWAIT); 924 if ((m->m_flags & M_EXT) == 0) { 925 m_free(m); 926 m = NULL; 927 } 928 } 929 if (m == NULL) 930 return; 931 m_reset_rcvif(m); 932 933 if (IN6_IS_ADDR_MULTICAST(&daddr6)) { 934 m->m_flags |= M_MCAST; 935 im6o.im6o_multicast_if_index = if_get_index(ifp); 936 im6o.im6o_multicast_hlim = 255; 937 im6o.im6o_multicast_loop = 0; 938 } 939 940 icmp6len = sizeof(*nd_na); 941 m->m_pkthdr.len = m->m_len = sizeof(struct ip6_hdr) + icmp6len; 942 m->m_data += max_linkhdr; /* or MH_ALIGN() equivalent? */ 943 944 /* fill neighbor advertisement packet */ 945 ip6 = mtod(m, struct ip6_hdr *); 946 ip6->ip6_flow = 0; 947 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 948 ip6->ip6_vfc |= IPV6_VERSION; 949 ip6->ip6_nxt = IPPROTO_ICMPV6; 950 ip6->ip6_hlim = 255; 951 if (IN6_IS_ADDR_UNSPECIFIED(&daddr6)) { 952 /* reply to DAD */ 953 daddr6.s6_addr16[0] = IPV6_ADDR_INT16_MLL; 954 daddr6.s6_addr16[1] = 0; 955 daddr6.s6_addr32[1] = 0; 956 daddr6.s6_addr32[2] = 0; 957 daddr6.s6_addr32[3] = IPV6_ADDR_INT32_ONE; 958 if (in6_setscope(&daddr6, ifp, NULL)) 959 goto bad; 960 961 flags &= ~ND_NA_FLAG_SOLICITED; 962 } 963 ip6->ip6_dst = daddr6; 964 sockaddr_in6_init(&u.dst6, &daddr6, 0, 0, 0); 965 dst = &u.dst; 966 if (rtcache_setdst(&ro, dst) != 0) 967 goto bad; 968 969 /* 970 * Select a source whose scope is the same as that of the dest. 971 */ 972 error = in6_selectsrc(satosin6(dst), NULL, NULL, &ro, NULL, NULL, NULL, 973 &ip6->ip6_src); 974 if (error != 0) { 975 nd6log(LOG_DEBUG, "source can't be " 976 "determined: dst=%s, error=%d\n", 977 ip6_sprintf(&satocsin6(dst)->sin6_addr), error); 978 goto bad; 979 } 980 nd_na = (struct nd_neighbor_advert *)(ip6 + 1); 981 nd_na->nd_na_type = ND_NEIGHBOR_ADVERT; 982 nd_na->nd_na_code = 0; 983 nd_na->nd_na_target = *taddr6; 984 in6_clearscope(&nd_na->nd_na_target); /* XXX */ 985 986 /* 987 * "tlladdr" indicates NS's condition for adding tlladdr or not. 988 * see nd6_ns_input() for details. 989 * Basically, if NS packet is sent to unicast/anycast addr, 990 * target lladdr option SHOULD NOT be included. 991 */ 992 if (tlladdr) { 993 /* 994 * sdl0 != NULL indicates proxy NA. If we do proxy, use 995 * lladdr in sdl0. If we are not proxying (sending NA for 996 * my address) use lladdr configured for the interface. 997 */ 998 if (sdl0 == NULL) 999 mac = nd6_ifptomac(ifp); 1000 else if (sdl0->sa_family == AF_LINK) { 1001 const struct sockaddr_dl *sdl; 1002 sdl = satocsdl(sdl0); 1003 if (sdl->sdl_alen == ifp->if_addrlen) 1004 mac = CLLADDR(sdl); 1005 } 1006 } 1007 if (tlladdr && mac) { 1008 int optlen = sizeof(struct nd_opt_hdr) + ifp->if_addrlen; 1009 struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)(nd_na + 1); 1010 1011 /* roundup to 8 bytes alignment! */ 1012 optlen = (optlen + 7) & ~7; 1013 1014 m->m_pkthdr.len += optlen; 1015 m->m_len += optlen; 1016 icmp6len += optlen; 1017 memset((void *)nd_opt, 0, optlen); 1018 nd_opt->nd_opt_type = ND_OPT_TARGET_LINKADDR; 1019 nd_opt->nd_opt_len = optlen >> 3; 1020 memcpy((void *)(nd_opt + 1), mac, ifp->if_addrlen); 1021 } else 1022 flags &= ~ND_NA_FLAG_OVERRIDE; 1023 1024 ip6->ip6_plen = htons((u_int16_t)icmp6len); 1025 nd_na->nd_na_flags_reserved = flags; 1026 nd_na->nd_na_cksum = 0; 1027 nd_na->nd_na_cksum = 1028 in6_cksum(m, IPPROTO_ICMPV6, sizeof(struct ip6_hdr), icmp6len); 1029 1030 ip6_output(m, NULL, NULL, 0, &im6o, NULL, NULL); 1031 1032 icmp6_ifstat_inc(ifp, ifs6_out_msg); 1033 icmp6_ifstat_inc(ifp, ifs6_out_neighboradvert); 1034 ICMP6_STATINC(ICMP6_STAT_OUTHIST + ND_NEIGHBOR_ADVERT); 1035 1036 rtcache_free(&ro); 1037 return; 1038 1039 bad: 1040 rtcache_free(&ro); 1041 m_freem(m); 1042 return; 1043 } 1044 1045 const void * 1046 nd6_ifptomac(const struct ifnet *ifp) 1047 { 1048 switch (ifp->if_type) { 1049 case IFT_ARCNET: 1050 case IFT_ETHER: 1051 case IFT_FDDI: 1052 case IFT_IEEE1394: 1053 case IFT_PROPVIRTUAL: 1054 case IFT_CARP: 1055 case IFT_L2VLAN: 1056 case IFT_IEEE80211: 1057 return CLLADDR(ifp->if_sadl); 1058 default: 1059 return NULL; 1060 } 1061 } 1062 1063 TAILQ_HEAD(dadq_head, dadq); 1064 struct dadq { 1065 TAILQ_ENTRY(dadq) dad_list; 1066 struct ifaddr *dad_ifa; 1067 int dad_count; /* max NS to send */ 1068 int dad_ns_tcount; /* # of trials to send NS */ 1069 int dad_ns_ocount; /* NS sent so far */ 1070 int dad_ns_icount; 1071 int dad_na_icount; 1072 struct callout dad_timer_ch; 1073 }; 1074 1075 static struct dadq_head dadq; 1076 static int dad_init = 0; 1077 static kmutex_t nd6_dad_lock; 1078 1079 static struct dadq * 1080 nd6_dad_find(struct ifaddr *ifa) 1081 { 1082 struct dadq *dp; 1083 1084 KASSERT(mutex_owned(&nd6_dad_lock)); 1085 1086 TAILQ_FOREACH(dp, &dadq, dad_list) { 1087 if (dp->dad_ifa == ifa) 1088 return dp; 1089 } 1090 return NULL; 1091 } 1092 1093 static void 1094 nd6_dad_starttimer(struct dadq *dp, int ticks) 1095 { 1096 1097 callout_reset(&dp->dad_timer_ch, ticks, 1098 (void (*)(void *))nd6_dad_timer, (void *)dp->dad_ifa); 1099 } 1100 1101 static void 1102 nd6_dad_stoptimer(struct dadq *dp) 1103 { 1104 1105 #ifdef NET_MPSAFE 1106 callout_halt(&dp->dad_timer_ch, NULL); 1107 #else 1108 callout_halt(&dp->dad_timer_ch, softnet_lock); 1109 #endif 1110 } 1111 1112 /* 1113 * Start Duplicate Address Detection (DAD) for specified interface address. 1114 * 1115 * Note that callout is used when xtick > 0 and not when xtick == 0. 1116 * 1117 * xtick: minimum delay ticks for IFF_UP event 1118 */ 1119 void 1120 nd6_dad_start(struct ifaddr *ifa, int xtick) 1121 { 1122 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1123 struct dadq *dp; 1124 1125 if (!dad_init) { 1126 TAILQ_INIT(&dadq); 1127 mutex_init(&nd6_dad_lock, MUTEX_DEFAULT, IPL_NONE); 1128 dad_init++; 1129 } 1130 1131 /* 1132 * If we don't need DAD, don't do it. 1133 * There are several cases: 1134 * - DAD is disabled (ip6_dad_count == 0) 1135 * - the interface address is anycast 1136 */ 1137 if (!(ia->ia6_flags & IN6_IFF_TENTATIVE)) { 1138 log(LOG_DEBUG, 1139 "nd6_dad_start: called with non-tentative address " 1140 "%s(%s)\n", 1141 ip6_sprintf(&ia->ia_addr.sin6_addr), 1142 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1143 return; 1144 } 1145 if (ia->ia6_flags & IN6_IFF_ANYCAST || !ip6_dad_count) { 1146 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1147 rt_newaddrmsg(RTM_NEWADDR, ifa, 0, NULL); 1148 return; 1149 } 1150 KASSERT(ifa->ifa_ifp != NULL); 1151 if (!(ifa->ifa_ifp->if_flags & IFF_UP)) 1152 return; 1153 1154 mutex_enter(&nd6_dad_lock); 1155 if (nd6_dad_find(ifa) != NULL) { 1156 mutex_exit(&nd6_dad_lock); 1157 /* DAD already in progress */ 1158 return; 1159 } 1160 1161 dp = malloc(sizeof(*dp), M_IP6NDP, M_NOWAIT); 1162 if (dp == NULL) { 1163 mutex_exit(&nd6_dad_lock); 1164 log(LOG_ERR, "nd6_dad_start: memory allocation failed for " 1165 "%s(%s)\n", 1166 ip6_sprintf(&ia->ia_addr.sin6_addr), 1167 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1168 return; 1169 } 1170 memset(dp, 0, sizeof(*dp)); 1171 callout_init(&dp->dad_timer_ch, CALLOUT_MPSAFE); 1172 1173 /* 1174 * Send NS packet for DAD, ip6_dad_count times. 1175 * Note that we must delay the first transmission, if this is the 1176 * first packet to be sent from the interface after interface 1177 * (re)initialization. 1178 */ 1179 dp->dad_ifa = ifa; 1180 ifaref(ifa); /* just for safety */ 1181 dp->dad_count = ip6_dad_count; 1182 dp->dad_ns_icount = dp->dad_na_icount = 0; 1183 dp->dad_ns_ocount = dp->dad_ns_tcount = 0; 1184 TAILQ_INSERT_TAIL(&dadq, (struct dadq *)dp, dad_list); 1185 1186 nd6log(LOG_DEBUG, "%s: starting DAD for %s\n", if_name(ifa->ifa_ifp), 1187 ip6_sprintf(&ia->ia_addr.sin6_addr)); 1188 1189 if (xtick == 0) { 1190 nd6_dad_ns_output(dp, ifa); 1191 nd6_dad_starttimer(dp, 1192 (long)ND_IFINFO(ifa->ifa_ifp)->retrans * hz / 1000); 1193 } else 1194 nd6_dad_starttimer(dp, xtick); 1195 mutex_exit(&nd6_dad_lock); 1196 } 1197 1198 /* 1199 * terminate DAD unconditionally. used for address removals. 1200 */ 1201 void 1202 nd6_dad_stop(struct ifaddr *ifa) 1203 { 1204 struct dadq *dp; 1205 1206 if (!dad_init) 1207 return; 1208 1209 mutex_enter(&nd6_dad_lock); 1210 dp = nd6_dad_find(ifa); 1211 if (dp == NULL) { 1212 mutex_exit(&nd6_dad_lock); 1213 /* DAD wasn't started yet */ 1214 return; 1215 } 1216 1217 /* Prevent the timer from running anymore. */ 1218 TAILQ_REMOVE(&dadq, dp, dad_list); 1219 mutex_exit(&nd6_dad_lock); 1220 1221 nd6_dad_stoptimer(dp); 1222 1223 free(dp, M_IP6NDP); 1224 dp = NULL; 1225 ifafree(ifa); 1226 } 1227 1228 static void 1229 nd6_dad_timer(struct ifaddr *ifa) 1230 { 1231 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1232 struct dadq *dp; 1233 int duplicate = 0; 1234 1235 #ifndef NET_MPSAFE 1236 mutex_enter(softnet_lock); 1237 KERNEL_LOCK(1, NULL); 1238 #endif 1239 mutex_enter(&nd6_dad_lock); 1240 1241 /* Sanity check */ 1242 if (ia == NULL) { 1243 log(LOG_ERR, "nd6_dad_timer: called with null parameter\n"); 1244 goto done; 1245 } 1246 dp = nd6_dad_find(ifa); 1247 if (dp == NULL) { 1248 /* DAD seems to be stopping, so do nothing. */ 1249 goto done; 1250 } 1251 if (ia->ia6_flags & IN6_IFF_DUPLICATED) { 1252 log(LOG_ERR, "nd6_dad_timer: called with duplicate address " 1253 "%s(%s)\n", 1254 ip6_sprintf(&ia->ia_addr.sin6_addr), 1255 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1256 goto done; 1257 } 1258 if ((ia->ia6_flags & IN6_IFF_TENTATIVE) == 0) { 1259 log(LOG_ERR, "nd6_dad_timer: called with non-tentative address " 1260 "%s(%s)\n", 1261 ip6_sprintf(&ia->ia_addr.sin6_addr), 1262 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1263 goto done; 1264 } 1265 1266 /* timeouted with IFF_{RUNNING,UP} check */ 1267 if (dp->dad_ns_tcount > dad_maxtry) { 1268 nd6log(LOG_INFO, "%s: could not run DAD, driver problem?\n", 1269 if_name(ifa->ifa_ifp)); 1270 1271 TAILQ_REMOVE(&dadq, dp, dad_list); 1272 free(dp, M_IP6NDP); 1273 dp = NULL; 1274 ifafree(ifa); 1275 goto done; 1276 } 1277 1278 /* Need more checks? */ 1279 if (dp->dad_ns_ocount < dp->dad_count) { 1280 /* 1281 * We have more NS to go. Send NS packet for DAD. 1282 */ 1283 nd6_dad_ns_output(dp, ifa); 1284 nd6_dad_starttimer(dp, 1285 (long)ND_IFINFO(ifa->ifa_ifp)->retrans * hz / 1000); 1286 } else { 1287 /* 1288 * We have transmitted sufficient number of DAD packets. 1289 * See what we've got. 1290 */ 1291 if (dp->dad_na_icount) { 1292 /* 1293 * the check is in nd6_dad_na_input(), 1294 * but just in case 1295 */ 1296 duplicate++; 1297 } 1298 1299 if (dp->dad_ns_icount) { 1300 /* We've seen NS, means DAD has failed. */ 1301 duplicate++; 1302 } 1303 1304 if (duplicate) { 1305 /* (*dp) will be freed in nd6_dad_duplicated() */ 1306 dp = NULL; 1307 } else { 1308 /* 1309 * We are done with DAD. No NA came, no NS came. 1310 * No duplicate address found. 1311 */ 1312 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1313 rt_newaddrmsg(RTM_NEWADDR, ifa, 0, NULL); 1314 1315 nd6log(LOG_DEBUG, 1316 "%s: DAD complete for %s - no duplicates found\n", 1317 if_name(ifa->ifa_ifp), 1318 ip6_sprintf(&ia->ia_addr.sin6_addr)); 1319 1320 TAILQ_REMOVE(&dadq, dp, dad_list); 1321 free(dp, M_IP6NDP); 1322 dp = NULL; 1323 ifafree(ifa); 1324 } 1325 } 1326 1327 done: 1328 mutex_exit(&nd6_dad_lock); 1329 1330 if (duplicate) 1331 nd6_dad_duplicated(ifa); 1332 1333 #ifndef NET_MPSAFE 1334 KERNEL_UNLOCK_ONE(NULL); 1335 mutex_exit(softnet_lock); 1336 #endif 1337 } 1338 1339 static void 1340 nd6_dad_duplicated(struct ifaddr *ifa) 1341 { 1342 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1343 struct ifnet *ifp; 1344 struct dadq *dp; 1345 1346 mutex_enter(&nd6_dad_lock); 1347 dp = nd6_dad_find(ifa); 1348 if (dp == NULL) { 1349 mutex_exit(&nd6_dad_lock); 1350 /* DAD seems to be stopping, so do nothing. */ 1351 return; 1352 } 1353 1354 ifp = ifa->ifa_ifp; 1355 log(LOG_ERR, "%s: DAD detected duplicate IPv6 address %s: " 1356 "NS in/out=%d/%d, NA in=%d\n", 1357 if_name(ifp), ip6_sprintf(&ia->ia_addr.sin6_addr), 1358 dp->dad_ns_icount, dp->dad_ns_ocount, dp->dad_na_icount); 1359 1360 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1361 ia->ia6_flags |= IN6_IFF_DUPLICATED; 1362 1363 /* We are done with DAD, with duplicated address found. (failure) */ 1364 nd6_dad_stoptimer(dp); 1365 1366 log(LOG_ERR, "%s: DAD complete for %s - duplicate found\n", 1367 if_name(ifp), ip6_sprintf(&ia->ia_addr.sin6_addr)); 1368 log(LOG_ERR, "%s: manual intervention required\n", 1369 if_name(ifp)); 1370 1371 /* Inform the routing socket that DAD has completed */ 1372 rt_newaddrmsg(RTM_NEWADDR, ifa, 0, NULL); 1373 1374 /* 1375 * If the address is a link-local address formed from an interface 1376 * identifier based on the hardware address which is supposed to be 1377 * uniquely assigned (e.g., EUI-64 for an Ethernet interface), IP 1378 * operation on the interface SHOULD be disabled. 1379 * [rfc2462bis-03 Section 5.4.5] 1380 */ 1381 if (IN6_IS_ADDR_LINKLOCAL(&ia->ia_addr.sin6_addr)) { 1382 struct in6_addr in6; 1383 1384 /* 1385 * To avoid over-reaction, we only apply this logic when we are 1386 * very sure that hardware addresses are supposed to be unique. 1387 */ 1388 switch (ifp->if_type) { 1389 case IFT_ETHER: 1390 case IFT_FDDI: 1391 case IFT_ATM: 1392 case IFT_IEEE1394: 1393 #ifdef IFT_IEEE80211 1394 case IFT_IEEE80211: 1395 #endif 1396 in6 = ia->ia_addr.sin6_addr; 1397 if (in6_get_hw_ifid(ifp, &in6) == 0 && 1398 IN6_ARE_ADDR_EQUAL(&ia->ia_addr.sin6_addr, &in6)) { 1399 ND_IFINFO(ifp)->flags |= ND6_IFF_IFDISABLED; 1400 log(LOG_ERR, "%s: possible hardware address " 1401 "duplication detected, disable IPv6\n", 1402 if_name(ifp)); 1403 } 1404 break; 1405 } 1406 } 1407 1408 TAILQ_REMOVE(&dadq, dp, dad_list); 1409 mutex_exit(&nd6_dad_lock); 1410 1411 free(dp, M_IP6NDP); 1412 dp = NULL; 1413 ifafree(ifa); 1414 } 1415 1416 static void 1417 nd6_dad_ns_output(struct dadq *dp, struct ifaddr *ifa) 1418 { 1419 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1420 struct ifnet *ifp = ifa->ifa_ifp; 1421 1422 dp->dad_ns_tcount++; 1423 if ((ifp->if_flags & IFF_UP) == 0) { 1424 #if 0 1425 printf("%s: interface down?\n", if_name(ifp)); 1426 #endif 1427 return; 1428 } 1429 if ((ifp->if_flags & IFF_RUNNING) == 0) { 1430 #if 0 1431 printf("%s: interface not running?\n", if_name(ifp)); 1432 #endif 1433 return; 1434 } 1435 1436 dp->dad_ns_tcount = 0; 1437 dp->dad_ns_ocount++; 1438 nd6_ns_output(ifp, NULL, &ia->ia_addr.sin6_addr, NULL, 1); 1439 } 1440 1441 static void 1442 nd6_dad_ns_input(struct ifaddr *ifa) 1443 { 1444 struct in6_ifaddr *ia; 1445 const struct in6_addr *taddr6; 1446 struct dadq *dp; 1447 int duplicate; 1448 1449 if (ifa == NULL) 1450 panic("ifa == NULL in nd6_dad_ns_input"); 1451 1452 ia = (struct in6_ifaddr *)ifa; 1453 taddr6 = &ia->ia_addr.sin6_addr; 1454 duplicate = 0; 1455 1456 mutex_enter(&nd6_dad_lock); 1457 dp = nd6_dad_find(ifa); 1458 1459 /* Quickhack - completely ignore DAD NS packets */ 1460 if (dad_ignore_ns) { 1461 nd6log(LOG_INFO, "ignoring DAD NS packet for " 1462 "address %s(%s)\n", ip6_sprintf(taddr6), 1463 if_name(ifa->ifa_ifp)); 1464 return; 1465 } 1466 1467 /* 1468 * if I'm yet to start DAD, someone else started using this address 1469 * first. I have a duplicate and you win. 1470 */ 1471 if (dp == NULL || dp->dad_ns_ocount == 0) 1472 duplicate++; 1473 1474 /* XXX more checks for loopback situation - see nd6_dad_timer too */ 1475 1476 if (duplicate) { 1477 dp = NULL; /* will be freed in nd6_dad_duplicated() */ 1478 mutex_exit(&nd6_dad_lock); 1479 nd6_dad_duplicated(ifa); 1480 } else { 1481 /* 1482 * not sure if I got a duplicate. 1483 * increment ns count and see what happens. 1484 */ 1485 if (dp) 1486 dp->dad_ns_icount++; 1487 mutex_exit(&nd6_dad_lock); 1488 } 1489 } 1490 1491 static void 1492 nd6_dad_na_input(struct ifaddr *ifa) 1493 { 1494 struct dadq *dp; 1495 1496 if (ifa == NULL) 1497 panic("ifa == NULL in nd6_dad_na_input"); 1498 1499 mutex_enter(&nd6_dad_lock); 1500 dp = nd6_dad_find(ifa); 1501 if (dp) 1502 dp->dad_na_icount++; 1503 mutex_exit(&nd6_dad_lock); 1504 1505 /* remove the address. */ 1506 nd6_dad_duplicated(ifa); 1507 } 1508