1 /* $FreeBSD$ */ 2 /* $KAME: nd6_nbr.c,v 1.86 2002/01/21 02:33:04 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 "opt_inet.h" 34 #include "opt_inet6.h" 35 #include "opt_ipsec.h" 36 37 #include <sys/param.h> 38 #include <sys/systm.h> 39 #include <sys/malloc.h> 40 #include <sys/mbuf.h> 41 #include <sys/socket.h> 42 #include <sys/sockio.h> 43 #include <sys/time.h> 44 #include <sys/kernel.h> 45 #include <sys/errno.h> 46 #include <sys/syslog.h> 47 #include <sys/queue.h> 48 #include <sys/callout.h> 49 50 #include <net/if.h> 51 #include <net/if_types.h> 52 #include <net/if_dl.h> 53 #include <net/route.h> 54 55 #include <netinet/in.h> 56 #include <netinet/in_var.h> 57 #include <netinet6/in6_var.h> 58 #include <netinet/ip6.h> 59 #include <netinet6/ip6_var.h> 60 #include <netinet6/nd6.h> 61 #include <netinet/icmp6.h> 62 63 #ifdef IPSEC 64 #include <netinet6/ipsec.h> 65 #ifdef INET6 66 #include <netinet6/ipsec6.h> 67 #endif 68 #endif 69 70 #include <net/net_osdep.h> 71 72 #define SDL(s) ((struct sockaddr_dl *)s) 73 74 struct dadq; 75 static struct dadq *nd6_dad_find __P((struct ifaddr *)); 76 static void nd6_dad_starttimer __P((struct dadq *, int)); 77 static void nd6_dad_stoptimer __P((struct dadq *)); 78 static void nd6_dad_timer __P((struct ifaddr *)); 79 static void nd6_dad_ns_output __P((struct dadq *, struct ifaddr *)); 80 static void nd6_dad_ns_input __P((struct ifaddr *)); 81 static void nd6_dad_na_input __P((struct ifaddr *)); 82 83 static int dad_ignore_ns = 0; /* ignore NS in DAD - specwise incorrect*/ 84 static int dad_maxtry = 15; /* max # of *tries* to transmit DAD packet */ 85 86 /* 87 * Input a Neighbor Solicitation Message. 88 * 89 * Based on RFC 2461 90 * Based on RFC 2462 (duplicated address detection) 91 */ 92 void 93 nd6_ns_input(m, off, icmp6len) 94 struct mbuf *m; 95 int off, icmp6len; 96 { 97 struct ifnet *ifp = m->m_pkthdr.rcvif; 98 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 99 struct nd_neighbor_solicit *nd_ns; 100 struct in6_addr saddr6 = ip6->ip6_src; 101 struct in6_addr daddr6 = ip6->ip6_dst; 102 struct in6_addr taddr6; 103 struct in6_addr myaddr6; 104 char *lladdr = NULL; 105 struct ifaddr *ifa; 106 int lladdrlen = 0; 107 int anycast = 0, proxy = 0, tentative = 0; 108 int tlladdr; 109 union nd_opts ndopts; 110 struct sockaddr_dl *proxydl = NULL; 111 112 #ifndef PULLDOWN_TEST 113 IP6_EXTHDR_CHECK(m, off, icmp6len,); 114 nd_ns = (struct nd_neighbor_solicit *)((caddr_t)ip6 + off); 115 #else 116 IP6_EXTHDR_GET(nd_ns, struct nd_neighbor_solicit *, m, off, icmp6len); 117 if (nd_ns == NULL) { 118 icmp6stat.icp6s_tooshort++; 119 return; 120 } 121 #endif 122 ip6 = mtod(m, struct ip6_hdr *); /* adjust pointer for safety */ 123 taddr6 = nd_ns->nd_ns_target; 124 125 if (ip6->ip6_hlim != 255) { 126 nd6log((LOG_ERR, 127 "nd6_ns_input: invalid hlim (%d) from %s to %s on %s\n", 128 ip6->ip6_hlim, ip6_sprintf(&ip6->ip6_src), 129 ip6_sprintf(&ip6->ip6_dst), if_name(ifp))); 130 goto bad; 131 } 132 133 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) { 134 /* dst has to be solicited node multicast address. */ 135 if (daddr6.s6_addr16[0] == IPV6_ADDR_INT16_MLL 136 /* don't check ifindex portion */ 137 && daddr6.s6_addr32[1] == 0 138 && daddr6.s6_addr32[2] == IPV6_ADDR_INT32_ONE 139 && daddr6.s6_addr8[12] == 0xff) { 140 ; /* good */ 141 } else { 142 nd6log((LOG_INFO, "nd6_ns_input: bad DAD packet " 143 "(wrong ip6 dst)\n")); 144 goto bad; 145 } 146 } 147 148 if (IN6_IS_ADDR_MULTICAST(&taddr6)) { 149 nd6log((LOG_INFO, "nd6_ns_input: bad NS target (multicast)\n")); 150 goto bad; 151 } 152 153 if (IN6_IS_SCOPE_LINKLOCAL(&taddr6)) 154 taddr6.s6_addr16[1] = htons(ifp->if_index); 155 156 icmp6len -= sizeof(*nd_ns); 157 nd6_option_init(nd_ns + 1, icmp6len, &ndopts); 158 if (nd6_options(&ndopts) < 0) { 159 nd6log((LOG_INFO, 160 "nd6_ns_input: invalid ND option, ignored\n")); 161 /* nd6_options have incremented stats */ 162 goto freeit; 163 } 164 165 if (ndopts.nd_opts_src_lladdr) { 166 lladdr = (char *)(ndopts.nd_opts_src_lladdr + 1); 167 lladdrlen = ndopts.nd_opts_src_lladdr->nd_opt_len << 3; 168 } 169 170 if (IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_src) && lladdr) { 171 nd6log((LOG_INFO, "nd6_ns_input: bad DAD packet " 172 "(link-layer address option)\n")); 173 goto bad; 174 } 175 176 /* 177 * Attaching target link-layer address to the NA? 178 * (RFC 2461 7.2.4) 179 * 180 * NS IP dst is unicast/anycast MUST NOT add 181 * NS IP dst is solicited-node multicast MUST add 182 * 183 * In implementation, we add target link-layer address by default. 184 * We do not add one in MUST NOT cases. 185 */ 186 #if 0 /* too much! */ 187 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &daddr6); 188 if (ifa && (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_ANYCAST)) 189 tlladdr = 0; 190 else 191 #endif 192 if (!IN6_IS_ADDR_MULTICAST(&daddr6)) 193 tlladdr = 0; 194 else 195 tlladdr = 1; 196 197 /* 198 * Target address (taddr6) must be either: 199 * (1) Valid unicast/anycast address for my receiving interface, 200 * (2) Unicast address for which I'm offering proxy service, or 201 * (3) "tentative" address on which DAD is being performed. 202 */ 203 /* (1) and (3) check. */ 204 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &taddr6); 205 206 /* (2) check. */ 207 if (!ifa) { 208 struct rtentry *rt; 209 struct sockaddr_in6 tsin6; 210 211 bzero(&tsin6, sizeof tsin6); 212 tsin6.sin6_len = sizeof(struct sockaddr_in6); 213 tsin6.sin6_family = AF_INET6; 214 tsin6.sin6_addr = taddr6; 215 216 rt = rtalloc1((struct sockaddr *)&tsin6, 0, 0); 217 if (rt && (rt->rt_flags & RTF_ANNOUNCE) != 0 && 218 rt->rt_gateway->sa_family == AF_LINK) { 219 /* 220 * proxy NDP for single entry 221 */ 222 ifa = (struct ifaddr *)in6ifa_ifpforlinklocal(ifp, 223 IN6_IFF_NOTREADY|IN6_IFF_ANYCAST); 224 if (ifa) { 225 proxy = 1; 226 proxydl = SDL(rt->rt_gateway); 227 } 228 } 229 if (rt) 230 rtfree(rt); 231 } 232 if (!ifa) { 233 /* 234 * We've got an NS packet, and we don't have that adddress 235 * assigned for us. We MUST silently ignore it. 236 * See RFC2461 7.2.3. 237 */ 238 goto freeit; 239 } 240 myaddr6 = *IFA_IN6(ifa); 241 anycast = ((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_ANYCAST; 242 tentative = ((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_TENTATIVE; 243 if (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_DUPLICATED) 244 goto freeit; 245 246 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) { 247 nd6log((LOG_INFO, 248 "nd6_ns_input: lladdrlen mismatch for %s " 249 "(if %d, NS packet %d)\n", 250 ip6_sprintf(&taddr6), ifp->if_addrlen, lladdrlen - 2)); 251 goto bad; 252 } 253 254 if (IN6_ARE_ADDR_EQUAL(&myaddr6, &saddr6)) { 255 nd6log((LOG_INFO, 256 "nd6_ns_input: duplicate IP6 address %s\n", 257 ip6_sprintf(&saddr6))); 258 goto freeit; 259 } 260 261 /* 262 * We have neighbor solicitation packet, with target address equals to 263 * one of my tentative address. 264 * 265 * src addr how to process? 266 * --- --- 267 * multicast of course, invalid (rejected in ip6_input) 268 * unicast somebody is doing address resolution -> ignore 269 * unspec dup address detection 270 * 271 * The processing is defined in RFC 2462. 272 */ 273 if (tentative) { 274 /* 275 * If source address is unspecified address, it is for 276 * duplicated address detection. 277 * 278 * If not, the packet is for addess resolution; 279 * silently ignore it. 280 */ 281 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) 282 nd6_dad_ns_input(ifa); 283 284 goto freeit; 285 } 286 287 /* 288 * If the source address is unspecified address, entries must not 289 * be created or updated. 290 * It looks that sender is performing DAD. Output NA toward 291 * all-node multicast address, to tell the sender that I'm using 292 * the address. 293 * S bit ("solicited") must be zero. 294 */ 295 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) { 296 saddr6 = in6addr_linklocal_allnodes; 297 saddr6.s6_addr16[1] = htons(ifp->if_index); 298 nd6_na_output(ifp, &saddr6, &taddr6, 299 ((anycast || proxy || !tlladdr) 300 ? 0 : ND_NA_FLAG_OVERRIDE) 301 | (ip6_forwarding ? ND_NA_FLAG_ROUTER : 0), 302 tlladdr, (struct sockaddr *)proxydl); 303 goto freeit; 304 } 305 306 nd6_cache_lladdr(ifp, &saddr6, lladdr, lladdrlen, ND_NEIGHBOR_SOLICIT, 0); 307 308 nd6_na_output(ifp, &saddr6, &taddr6, 309 ((anycast || proxy || !tlladdr) ? 0 : ND_NA_FLAG_OVERRIDE) 310 | (ip6_forwarding ? ND_NA_FLAG_ROUTER : 0) 311 | ND_NA_FLAG_SOLICITED, 312 tlladdr, (struct sockaddr *)proxydl); 313 freeit: 314 m_freem(m); 315 return; 316 317 bad: 318 nd6log((LOG_ERR, "nd6_ns_input: src=%s\n", ip6_sprintf(&saddr6))); 319 nd6log((LOG_ERR, "nd6_ns_input: dst=%s\n", ip6_sprintf(&daddr6))); 320 nd6log((LOG_ERR, "nd6_ns_input: tgt=%s\n", ip6_sprintf(&taddr6))); 321 icmp6stat.icp6s_badns++; 322 m_freem(m); 323 } 324 325 /* 326 * Output a Neighbor Solicitation Message. Caller specifies: 327 * - ICMP6 header source IP6 address 328 * - ND6 header target IP6 address 329 * - ND6 header source datalink address 330 * 331 * Based on RFC 2461 332 * Based on RFC 2462 (duplicated address detection) 333 */ 334 void 335 nd6_ns_output(ifp, daddr6, taddr6, ln, dad) 336 struct ifnet *ifp; 337 const struct in6_addr *daddr6, *taddr6; 338 struct llinfo_nd6 *ln; /* for source address determination */ 339 int dad; /* duplicated address detection */ 340 { 341 struct mbuf *m; 342 struct ip6_hdr *ip6; 343 struct nd_neighbor_solicit *nd_ns; 344 struct in6_ifaddr *ia = NULL; 345 struct ip6_moptions im6o; 346 int icmp6len; 347 int maxlen; 348 caddr_t mac; 349 struct ifnet *outif = NULL; 350 351 if (IN6_IS_ADDR_MULTICAST(taddr6)) 352 return; 353 354 /* estimate the size of message */ 355 maxlen = sizeof(*ip6) + sizeof(*nd_ns); 356 maxlen += (sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7; 357 if (max_linkhdr + maxlen >= MCLBYTES) { 358 #ifdef DIAGNOSTIC 359 printf("nd6_ns_output: max_linkhdr + maxlen >= MCLBYTES " 360 "(%d + %d > %d)\n", max_linkhdr, maxlen, MCLBYTES); 361 #endif 362 return; 363 } 364 365 MGETHDR(m, M_DONTWAIT, MT_DATA); 366 if (m && max_linkhdr + maxlen >= MHLEN) { 367 MCLGET(m, M_DONTWAIT); 368 if ((m->m_flags & M_EXT) == 0) { 369 m_free(m); 370 m = NULL; 371 } 372 } 373 if (m == NULL) 374 return; 375 m->m_pkthdr.rcvif = NULL; 376 377 if (daddr6 == NULL || IN6_IS_ADDR_MULTICAST(daddr6)) { 378 m->m_flags |= M_MCAST; 379 im6o.im6o_multicast_ifp = ifp; 380 im6o.im6o_multicast_hlim = 255; 381 im6o.im6o_multicast_loop = 0; 382 } 383 384 icmp6len = sizeof(*nd_ns); 385 m->m_pkthdr.len = m->m_len = sizeof(*ip6) + icmp6len; 386 m->m_data += max_linkhdr; /* or MH_ALIGN() equivalent? */ 387 388 /* fill neighbor solicitation packet */ 389 ip6 = mtod(m, struct ip6_hdr *); 390 ip6->ip6_flow = 0; 391 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 392 ip6->ip6_vfc |= IPV6_VERSION; 393 /* ip6->ip6_plen will be set later */ 394 ip6->ip6_nxt = IPPROTO_ICMPV6; 395 ip6->ip6_hlim = 255; 396 if (daddr6) 397 ip6->ip6_dst = *daddr6; 398 else { 399 ip6->ip6_dst.s6_addr16[0] = IPV6_ADDR_INT16_MLL; 400 ip6->ip6_dst.s6_addr16[1] = htons(ifp->if_index); 401 ip6->ip6_dst.s6_addr32[1] = 0; 402 ip6->ip6_dst.s6_addr32[2] = IPV6_ADDR_INT32_ONE; 403 ip6->ip6_dst.s6_addr32[3] = taddr6->s6_addr32[3]; 404 ip6->ip6_dst.s6_addr8[12] = 0xff; 405 } 406 if (!dad) { 407 #if 0 /* KAME way, exact address scope match */ 408 /* 409 * Select a source whose scope is the same as that of the dest. 410 * Typically, the dest is link-local solicitation multicast 411 * (i.e. neighbor discovery) or link-local/global unicast 412 * (i.e. neighbor un-reachability detection). 413 */ 414 ia = in6_ifawithifp(ifp, &ip6->ip6_dst); 415 if (ia == NULL) { 416 m_freem(m); 417 return; 418 } 419 ip6->ip6_src = ia->ia_addr.sin6_addr; 420 #else /* spec-wise correct */ 421 /* 422 * RFC2461 7.2.2: 423 * "If the source address of the packet prompting the 424 * solicitation is the same as one of the addresses assigned 425 * to the outgoing interface, that address SHOULD be placed 426 * in the IP Source Address of the outgoing solicitation. 427 * Otherwise, any one of the addresses assigned to the 428 * interface should be used." 429 * 430 * We use the source address for the prompting packet 431 * (saddr6), if: 432 * - saddr6 is given from the caller (by giving "ln"), and 433 * - saddr6 belongs to the outgoing interface. 434 * Otherwise, we perform a scope-wise match. 435 */ 436 struct ip6_hdr *hip6; /* hold ip6 */ 437 struct in6_addr *saddr6; 438 439 if (ln && ln->ln_hold) { 440 hip6 = mtod(ln->ln_hold, struct ip6_hdr *); 441 /* XXX pullup? */ 442 if (sizeof(*hip6) < ln->ln_hold->m_len) 443 saddr6 = &hip6->ip6_src; 444 else 445 saddr6 = NULL; 446 } else 447 saddr6 = NULL; 448 if (saddr6 && in6ifa_ifpwithaddr(ifp, saddr6)) 449 bcopy(saddr6, &ip6->ip6_src, sizeof(*saddr6)); 450 else { 451 ia = in6_ifawithifp(ifp, &ip6->ip6_dst); 452 if (ia == NULL) { 453 m_freem(m); 454 return; 455 } 456 ip6->ip6_src = ia->ia_addr.sin6_addr; 457 } 458 #endif 459 } else { 460 /* 461 * Source address for DAD packet must always be IPv6 462 * unspecified address. (0::0) 463 */ 464 bzero(&ip6->ip6_src, sizeof(ip6->ip6_src)); 465 } 466 nd_ns = (struct nd_neighbor_solicit *)(ip6 + 1); 467 nd_ns->nd_ns_type = ND_NEIGHBOR_SOLICIT; 468 nd_ns->nd_ns_code = 0; 469 nd_ns->nd_ns_reserved = 0; 470 nd_ns->nd_ns_target = *taddr6; 471 472 if (IN6_IS_SCOPE_LINKLOCAL(&nd_ns->nd_ns_target)) 473 nd_ns->nd_ns_target.s6_addr16[1] = 0; 474 475 /* 476 * Add source link-layer address option. 477 * 478 * spec implementation 479 * --- --- 480 * DAD packet MUST NOT do not add the option 481 * there's no link layer address: 482 * impossible do not add the option 483 * there's link layer address: 484 * Multicast NS MUST add one add the option 485 * Unicast NS SHOULD add one add the option 486 */ 487 if (!dad && (mac = nd6_ifptomac(ifp))) { 488 int optlen = sizeof(struct nd_opt_hdr) + ifp->if_addrlen; 489 struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)(nd_ns + 1); 490 /* 8 byte alignments... */ 491 optlen = (optlen + 7) & ~7; 492 493 m->m_pkthdr.len += optlen; 494 m->m_len += optlen; 495 icmp6len += optlen; 496 bzero((caddr_t)nd_opt, optlen); 497 nd_opt->nd_opt_type = ND_OPT_SOURCE_LINKADDR; 498 nd_opt->nd_opt_len = optlen >> 3; 499 bcopy(mac, (caddr_t)(nd_opt + 1), ifp->if_addrlen); 500 } 501 502 ip6->ip6_plen = htons((u_short)icmp6len); 503 nd_ns->nd_ns_cksum = 0; 504 nd_ns->nd_ns_cksum 505 = in6_cksum(m, IPPROTO_ICMPV6, sizeof(*ip6), icmp6len); 506 507 ip6_output(m, NULL, NULL, dad ? IPV6_DADOUTPUT : 0, &im6o, &outif, NULL); 508 if (outif) { 509 icmp6_ifstat_inc(outif, ifs6_out_msg); 510 icmp6_ifstat_inc(outif, ifs6_out_neighborsolicit); 511 } 512 icmp6stat.icp6s_outhist[ND_NEIGHBOR_SOLICIT]++; 513 } 514 515 /* 516 * Neighbor advertisement input handling. 517 * 518 * Based on RFC 2461 519 * Based on RFC 2462 (duplicated address detection) 520 * 521 * the following items are not implemented yet: 522 * - proxy advertisement delay rule (RFC2461 7.2.8, last paragraph, SHOULD) 523 * - anycast advertisement delay rule (RFC2461 7.2.7, SHOULD) 524 */ 525 void 526 nd6_na_input(m, off, icmp6len) 527 struct mbuf *m; 528 int off, icmp6len; 529 { 530 struct ifnet *ifp = m->m_pkthdr.rcvif; 531 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 532 struct nd_neighbor_advert *nd_na; 533 #if 0 534 struct in6_addr saddr6 = ip6->ip6_src; 535 #endif 536 struct in6_addr daddr6 = ip6->ip6_dst; 537 struct in6_addr taddr6; 538 int flags; 539 int is_router; 540 int is_solicited; 541 int is_override; 542 char *lladdr = NULL; 543 int lladdrlen = 0; 544 struct ifaddr *ifa; 545 struct llinfo_nd6 *ln; 546 struct rtentry *rt; 547 struct sockaddr_dl *sdl; 548 union nd_opts ndopts; 549 550 if (ip6->ip6_hlim != 255) { 551 nd6log((LOG_ERR, 552 "nd6_na_input: invalid hlim (%d) from %s to %s on %s\n", 553 ip6->ip6_hlim, ip6_sprintf(&ip6->ip6_src), 554 ip6_sprintf(&ip6->ip6_dst), if_name(ifp))); 555 goto bad; 556 } 557 558 #ifndef PULLDOWN_TEST 559 IP6_EXTHDR_CHECK(m, off, icmp6len,); 560 nd_na = (struct nd_neighbor_advert *)((caddr_t)ip6 + off); 561 #else 562 IP6_EXTHDR_GET(nd_na, struct nd_neighbor_advert *, m, off, icmp6len); 563 if (nd_na == NULL) { 564 icmp6stat.icp6s_tooshort++; 565 return; 566 } 567 #endif 568 taddr6 = nd_na->nd_na_target; 569 flags = nd_na->nd_na_flags_reserved; 570 is_router = ((flags & ND_NA_FLAG_ROUTER) != 0); 571 is_solicited = ((flags & ND_NA_FLAG_SOLICITED) != 0); 572 is_override = ((flags & ND_NA_FLAG_OVERRIDE) != 0); 573 574 if (IN6_IS_SCOPE_LINKLOCAL(&taddr6)) 575 taddr6.s6_addr16[1] = htons(ifp->if_index); 576 577 if (IN6_IS_ADDR_MULTICAST(&taddr6)) { 578 nd6log((LOG_ERR, 579 "nd6_na_input: invalid target address %s\n", 580 ip6_sprintf(&taddr6))); 581 goto bad; 582 } 583 if (IN6_IS_ADDR_MULTICAST(&daddr6)) 584 if (is_solicited) { 585 nd6log((LOG_ERR, 586 "nd6_na_input: a solicited adv is multicasted\n")); 587 goto bad; 588 } 589 590 icmp6len -= sizeof(*nd_na); 591 nd6_option_init(nd_na + 1, icmp6len, &ndopts); 592 if (nd6_options(&ndopts) < 0) { 593 nd6log((LOG_INFO, 594 "nd6_na_input: invalid ND option, ignored\n")); 595 /* nd6_options have incremented stats */ 596 goto freeit; 597 } 598 599 if (ndopts.nd_opts_tgt_lladdr) { 600 lladdr = (char *)(ndopts.nd_opts_tgt_lladdr + 1); 601 lladdrlen = ndopts.nd_opts_tgt_lladdr->nd_opt_len << 3; 602 } 603 604 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &taddr6); 605 606 /* 607 * Target address matches one of my interface address. 608 * 609 * If my address is tentative, this means that there's somebody 610 * already using the same address as mine. This indicates DAD failure. 611 * This is defined in RFC 2462. 612 * 613 * Otherwise, process as defined in RFC 2461. 614 */ 615 if (ifa 616 && (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_TENTATIVE)) { 617 nd6_dad_na_input(ifa); 618 goto freeit; 619 } 620 621 /* Just for safety, maybe unnecessary. */ 622 if (ifa) { 623 log(LOG_ERR, 624 "nd6_na_input: duplicate IP6 address %s\n", 625 ip6_sprintf(&taddr6)); 626 goto freeit; 627 } 628 629 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) { 630 nd6log((LOG_INFO, 631 "nd6_na_input: lladdrlen mismatch for %s " 632 "(if %d, NA packet %d)\n", 633 ip6_sprintf(&taddr6), ifp->if_addrlen, lladdrlen - 2)); 634 goto bad; 635 } 636 637 /* 638 * If no neighbor cache entry is found, NA SHOULD silently be discarded. 639 */ 640 rt = nd6_lookup(&taddr6, 0, ifp); 641 if ((rt == NULL) || 642 ((ln = (struct llinfo_nd6 *)rt->rt_llinfo) == NULL) || 643 ((sdl = SDL(rt->rt_gateway)) == NULL)) 644 goto freeit; 645 646 if (ln->ln_state == ND6_LLINFO_INCOMPLETE) { 647 /* 648 * If the link-layer has address, and no lladdr option came, 649 * discard the packet. 650 */ 651 if (ifp->if_addrlen && !lladdr) 652 goto freeit; 653 654 /* 655 * Record link-layer address, and update the state. 656 */ 657 sdl->sdl_alen = ifp->if_addrlen; 658 bcopy(lladdr, LLADDR(sdl), ifp->if_addrlen); 659 if (is_solicited) { 660 ln->ln_state = ND6_LLINFO_REACHABLE; 661 ln->ln_byhint = 0; 662 if (ln->ln_expire) 663 ln->ln_expire = time_second + 664 nd_ifinfo[rt->rt_ifp->if_index].reachable; 665 } else { 666 ln->ln_state = ND6_LLINFO_STALE; 667 ln->ln_expire = time_second + nd6_gctimer; 668 } 669 if ((ln->ln_router = is_router) != 0) { 670 /* 671 * This means a router's state has changed from 672 * non-reachable to probably reachable, and might 673 * affect the status of associated prefixes.. 674 */ 675 pfxlist_onlink_check(); 676 } 677 } else { 678 int llchange; 679 680 /* 681 * Check if the link-layer address has changed or not. 682 */ 683 if (!lladdr) 684 llchange = 0; 685 else { 686 if (sdl->sdl_alen) { 687 if (bcmp(lladdr, LLADDR(sdl), ifp->if_addrlen)) 688 llchange = 1; 689 else 690 llchange = 0; 691 } else 692 llchange = 1; 693 } 694 695 /* 696 * This is VERY complex. Look at it with care. 697 * 698 * override solicit lladdr llchange action 699 * (L: record lladdr) 700 * 701 * 0 0 n -- (2c) 702 * 0 0 y n (2b) L 703 * 0 0 y y (1) REACHABLE->STALE 704 * 0 1 n -- (2c) *->REACHABLE 705 * 0 1 y n (2b) L *->REACHABLE 706 * 0 1 y y (1) REACHABLE->STALE 707 * 1 0 n -- (2a) 708 * 1 0 y n (2a) L 709 * 1 0 y y (2a) L *->STALE 710 * 1 1 n -- (2a) *->REACHABLE 711 * 1 1 y n (2a) L *->REACHABLE 712 * 1 1 y y (2a) L *->REACHABLE 713 */ 714 if (!is_override && (lladdr && llchange)) { /* (1) */ 715 /* 716 * If state is REACHABLE, make it STALE. 717 * no other updates should be done. 718 */ 719 if (ln->ln_state == ND6_LLINFO_REACHABLE) { 720 ln->ln_state = ND6_LLINFO_STALE; 721 ln->ln_expire = time_second + nd6_gctimer; 722 } 723 goto freeit; 724 } else if (is_override /* (2a) */ 725 || (!is_override && (lladdr && !llchange)) /* (2b) */ 726 || !lladdr) { /* (2c) */ 727 /* 728 * Update link-local address, if any. 729 */ 730 if (lladdr) { 731 sdl->sdl_alen = ifp->if_addrlen; 732 bcopy(lladdr, LLADDR(sdl), ifp->if_addrlen); 733 } 734 735 /* 736 * If solicited, make the state REACHABLE. 737 * If not solicited and the link-layer address was 738 * changed, make it STALE. 739 */ 740 if (is_solicited) { 741 ln->ln_state = ND6_LLINFO_REACHABLE; 742 ln->ln_byhint = 0; 743 if (ln->ln_expire) { 744 ln->ln_expire = time_second + 745 nd_ifinfo[ifp->if_index].reachable; 746 } 747 } else { 748 if (lladdr && llchange) { 749 ln->ln_state = ND6_LLINFO_STALE; 750 ln->ln_expire = time_second + nd6_gctimer; 751 } 752 } 753 } 754 755 if (ln->ln_router && !is_router) { 756 /* 757 * The peer dropped the router flag. 758 * Remove the sender from the Default Router List and 759 * update the Destination Cache entries. 760 */ 761 struct nd_defrouter *dr; 762 struct in6_addr *in6; 763 int s; 764 765 in6 = &((struct sockaddr_in6 *)rt_key(rt))->sin6_addr; 766 767 /* 768 * Lock to protect the default router list. 769 * XXX: this might be unnecessary, since this function 770 * is only called under the network software interrupt 771 * context. However, we keep it just for safety. 772 */ 773 s = splnet(); 774 dr = defrouter_lookup(in6, rt->rt_ifp); 775 if (dr) 776 defrtrlist_del(dr); 777 else if (!ip6_forwarding && ip6_accept_rtadv) { 778 /* 779 * Even if the neighbor is not in the default 780 * router list, the neighbor may be used 781 * as a next hop for some destinations 782 * (e.g. redirect case). So we must 783 * call rt6_flush explicitly. 784 */ 785 rt6_flush(&ip6->ip6_src, rt->rt_ifp); 786 } 787 splx(s); 788 } 789 ln->ln_router = is_router; 790 } 791 rt->rt_flags &= ~RTF_REJECT; 792 ln->ln_asked = 0; 793 if (ln->ln_hold) { 794 /* 795 * we assume ifp is not a loopback here, so just set the 2nd 796 * argument as the 1st one. 797 */ 798 nd6_output(ifp, ifp, ln->ln_hold, 799 (struct sockaddr_in6 *)rt_key(rt), rt); 800 ln->ln_hold = 0; 801 } 802 803 freeit: 804 m_freem(m); 805 return; 806 807 bad: 808 icmp6stat.icp6s_badna++; 809 m_freem(m); 810 } 811 812 /* 813 * Neighbor advertisement output handling. 814 * 815 * Based on RFC 2461 816 * 817 * the following items are not implemented yet: 818 * - proxy advertisement delay rule (RFC2461 7.2.8, last paragraph, SHOULD) 819 * - anycast advertisement delay rule (RFC2461 7.2.7, SHOULD) 820 */ 821 void 822 nd6_na_output(ifp, daddr6, taddr6, flags, tlladdr, sdl0) 823 struct ifnet *ifp; 824 const struct in6_addr *daddr6, *taddr6; 825 u_long flags; 826 int tlladdr; /* 1 if include target link-layer address */ 827 struct sockaddr *sdl0; /* sockaddr_dl (= proxy NA) or NULL */ 828 { 829 struct mbuf *m; 830 struct ip6_hdr *ip6; 831 struct nd_neighbor_advert *nd_na; 832 struct in6_ifaddr *ia = NULL; 833 struct ip6_moptions im6o; 834 int icmp6len; 835 int maxlen; 836 caddr_t mac = NULL; 837 struct ifnet *outif = NULL; 838 839 /* estimate the size of message */ 840 maxlen = sizeof(*ip6) + sizeof(*nd_na); 841 maxlen += (sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7; 842 if (max_linkhdr + maxlen >= MCLBYTES) { 843 #ifdef DIAGNOSTIC 844 printf("nd6_na_output: max_linkhdr + maxlen >= MCLBYTES " 845 "(%d + %d > %d)\n", max_linkhdr, maxlen, MCLBYTES); 846 #endif 847 return; 848 } 849 850 MGETHDR(m, M_DONTWAIT, MT_DATA); 851 if (m && max_linkhdr + maxlen >= MHLEN) { 852 MCLGET(m, M_DONTWAIT); 853 if ((m->m_flags & M_EXT) == 0) { 854 m_free(m); 855 m = NULL; 856 } 857 } 858 if (m == NULL) 859 return; 860 m->m_pkthdr.rcvif = NULL; 861 862 if (IN6_IS_ADDR_MULTICAST(daddr6)) { 863 m->m_flags |= M_MCAST; 864 im6o.im6o_multicast_ifp = ifp; 865 im6o.im6o_multicast_hlim = 255; 866 im6o.im6o_multicast_loop = 0; 867 } 868 869 icmp6len = sizeof(*nd_na); 870 m->m_pkthdr.len = m->m_len = sizeof(struct ip6_hdr) + icmp6len; 871 m->m_data += max_linkhdr; /* or MH_ALIGN() equivalent? */ 872 873 /* fill neighbor advertisement packet */ 874 ip6 = mtod(m, struct ip6_hdr *); 875 ip6->ip6_flow = 0; 876 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 877 ip6->ip6_vfc |= IPV6_VERSION; 878 ip6->ip6_nxt = IPPROTO_ICMPV6; 879 ip6->ip6_hlim = 255; 880 if (IN6_IS_ADDR_UNSPECIFIED(daddr6)) { 881 /* reply to DAD */ 882 ip6->ip6_dst.s6_addr16[0] = IPV6_ADDR_INT16_MLL; 883 ip6->ip6_dst.s6_addr16[1] = htons(ifp->if_index); 884 ip6->ip6_dst.s6_addr32[1] = 0; 885 ip6->ip6_dst.s6_addr32[2] = 0; 886 ip6->ip6_dst.s6_addr32[3] = IPV6_ADDR_INT32_ONE; 887 flags &= ~ND_NA_FLAG_SOLICITED; 888 } else 889 ip6->ip6_dst = *daddr6; 890 891 /* 892 * Select a source whose scope is the same as that of the dest. 893 */ 894 ia = in6_ifawithifp(ifp, &ip6->ip6_dst); 895 if (ia == NULL) { 896 m_freem(m); 897 return; 898 } 899 ip6->ip6_src = ia->ia_addr.sin6_addr; 900 nd_na = (struct nd_neighbor_advert *)(ip6 + 1); 901 nd_na->nd_na_type = ND_NEIGHBOR_ADVERT; 902 nd_na->nd_na_code = 0; 903 nd_na->nd_na_target = *taddr6; 904 if (IN6_IS_SCOPE_LINKLOCAL(&nd_na->nd_na_target)) 905 nd_na->nd_na_target.s6_addr16[1] = 0; 906 907 /* 908 * "tlladdr" indicates NS's condition for adding tlladdr or not. 909 * see nd6_ns_input() for details. 910 * Basically, if NS packet is sent to unicast/anycast addr, 911 * target lladdr option SHOULD NOT be included. 912 */ 913 if (tlladdr) { 914 /* 915 * sdl0 != NULL indicates proxy NA. If we do proxy, use 916 * lladdr in sdl0. If we are not proxying (sending NA for 917 * my address) use lladdr configured for the interface. 918 */ 919 if (sdl0 == NULL) 920 mac = nd6_ifptomac(ifp); 921 else if (sdl0->sa_family == AF_LINK) { 922 struct sockaddr_dl *sdl; 923 sdl = (struct sockaddr_dl *)sdl0; 924 if (sdl->sdl_alen == ifp->if_addrlen) 925 mac = LLADDR(sdl); 926 } 927 } 928 if (tlladdr && mac) { 929 int optlen = sizeof(struct nd_opt_hdr) + ifp->if_addrlen; 930 struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)(nd_na + 1); 931 932 /* roundup to 8 bytes alignment! */ 933 optlen = (optlen + 7) & ~7; 934 935 m->m_pkthdr.len += optlen; 936 m->m_len += optlen; 937 icmp6len += optlen; 938 bzero((caddr_t)nd_opt, optlen); 939 nd_opt->nd_opt_type = ND_OPT_TARGET_LINKADDR; 940 nd_opt->nd_opt_len = optlen >> 3; 941 bcopy(mac, (caddr_t)(nd_opt + 1), ifp->if_addrlen); 942 } else 943 flags &= ~ND_NA_FLAG_OVERRIDE; 944 945 ip6->ip6_plen = htons((u_short)icmp6len); 946 nd_na->nd_na_flags_reserved = flags; 947 nd_na->nd_na_cksum = 0; 948 nd_na->nd_na_cksum = 949 in6_cksum(m, IPPROTO_ICMPV6, sizeof(struct ip6_hdr), icmp6len); 950 951 ip6_output(m, NULL, NULL, 0, &im6o, &outif, NULL); 952 if (outif) { 953 icmp6_ifstat_inc(outif, ifs6_out_msg); 954 icmp6_ifstat_inc(outif, ifs6_out_neighboradvert); 955 } 956 icmp6stat.icp6s_outhist[ND_NEIGHBOR_ADVERT]++; 957 } 958 959 caddr_t 960 nd6_ifptomac(ifp) 961 struct ifnet *ifp; 962 { 963 switch (ifp->if_type) { 964 case IFT_ARCNET: 965 case IFT_ETHER: 966 case IFT_FDDI: 967 case IFT_IEEE1394: 968 #ifdef IFT_L2VLAN 969 case IFT_L2VLAN: 970 #endif 971 #ifdef IFT_IEEE80211 972 case IFT_IEEE80211: 973 #endif 974 case IFT_ISO88025: 975 return ((caddr_t)(ifp + 1)); 976 break; 977 default: 978 return NULL; 979 } 980 } 981 982 TAILQ_HEAD(dadq_head, dadq); 983 struct dadq { 984 TAILQ_ENTRY(dadq) dad_list; 985 struct ifaddr *dad_ifa; 986 int dad_count; /* max NS to send */ 987 int dad_ns_tcount; /* # of trials to send NS */ 988 int dad_ns_ocount; /* NS sent so far */ 989 int dad_ns_icount; 990 int dad_na_icount; 991 struct callout dad_timer_ch; 992 }; 993 994 static struct dadq_head dadq; 995 static int dad_init = 0; 996 997 static struct dadq * 998 nd6_dad_find(ifa) 999 struct ifaddr *ifa; 1000 { 1001 struct dadq *dp; 1002 1003 for (dp = dadq.tqh_first; dp; dp = dp->dad_list.tqe_next) { 1004 if (dp->dad_ifa == ifa) 1005 return dp; 1006 } 1007 return NULL; 1008 } 1009 1010 static void 1011 nd6_dad_starttimer(dp, ticks) 1012 struct dadq *dp; 1013 int ticks; 1014 { 1015 1016 callout_reset(&dp->dad_timer_ch, ticks, 1017 (void (*) __P((void *)))nd6_dad_timer, (void *)dp->dad_ifa); 1018 } 1019 1020 static void 1021 nd6_dad_stoptimer(dp) 1022 struct dadq *dp; 1023 { 1024 1025 callout_stop(&dp->dad_timer_ch); 1026 } 1027 1028 /* 1029 * Start Duplicated Address Detection (DAD) for specified interface address. 1030 */ 1031 void 1032 nd6_dad_start(ifa, tick) 1033 struct ifaddr *ifa; 1034 int *tick; /* minimum delay ticks for IFF_UP event */ 1035 { 1036 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1037 struct dadq *dp; 1038 1039 if (!dad_init) { 1040 TAILQ_INIT(&dadq); 1041 dad_init++; 1042 } 1043 1044 /* 1045 * If we don't need DAD, don't do it. 1046 * There are several cases: 1047 * - DAD is disabled (ip6_dad_count == 0) 1048 * - the interface address is anycast 1049 */ 1050 if (!(ia->ia6_flags & IN6_IFF_TENTATIVE)) { 1051 log(LOG_DEBUG, 1052 "nd6_dad_start: called with non-tentative address " 1053 "%s(%s)\n", 1054 ip6_sprintf(&ia->ia_addr.sin6_addr), 1055 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1056 return; 1057 } 1058 if (ia->ia6_flags & IN6_IFF_ANYCAST) { 1059 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1060 return; 1061 } 1062 if (!ip6_dad_count) { 1063 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1064 return; 1065 } 1066 if (!ifa->ifa_ifp) 1067 panic("nd6_dad_start: ifa->ifa_ifp == NULL"); 1068 if (!(ifa->ifa_ifp->if_flags & IFF_UP)) 1069 return; 1070 if (nd6_dad_find(ifa) != NULL) { 1071 /* DAD already in progress */ 1072 return; 1073 } 1074 1075 dp = malloc(sizeof(*dp), M_IP6NDP, M_NOWAIT); 1076 if (dp == NULL) { 1077 log(LOG_ERR, "nd6_dad_start: memory allocation failed for " 1078 "%s(%s)\n", 1079 ip6_sprintf(&ia->ia_addr.sin6_addr), 1080 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1081 return; 1082 } 1083 bzero(dp, sizeof(*dp)); 1084 callout_init(&dp->dad_timer_ch, 0); 1085 TAILQ_INSERT_TAIL(&dadq, (struct dadq *)dp, dad_list); 1086 1087 nd6log((LOG_DEBUG, "%s: starting DAD for %s\n", if_name(ifa->ifa_ifp), 1088 ip6_sprintf(&ia->ia_addr.sin6_addr))); 1089 1090 /* 1091 * Send NS packet for DAD, ip6_dad_count times. 1092 * Note that we must delay the first transmission, if this is the 1093 * first packet to be sent from the interface after interface 1094 * (re)initialization. 1095 */ 1096 dp->dad_ifa = ifa; 1097 IFAREF(ifa); /* just for safety */ 1098 dp->dad_count = ip6_dad_count; 1099 dp->dad_ns_icount = dp->dad_na_icount = 0; 1100 dp->dad_ns_ocount = dp->dad_ns_tcount = 0; 1101 if (tick == NULL) { 1102 nd6_dad_ns_output(dp, ifa); 1103 nd6_dad_starttimer(dp, 1104 nd_ifinfo[ifa->ifa_ifp->if_index].retrans * hz / 1000); 1105 } else { 1106 int ntick; 1107 1108 if (*tick == 0) 1109 ntick = random() % (MAX_RTR_SOLICITATION_DELAY * hz); 1110 else 1111 ntick = *tick + random() % (hz / 2); 1112 *tick = ntick; 1113 nd6_dad_starttimer(dp, ntick); 1114 } 1115 } 1116 1117 /* 1118 * terminate DAD unconditionally. used for address removals. 1119 */ 1120 void 1121 nd6_dad_stop(ifa) 1122 struct ifaddr *ifa; 1123 { 1124 struct dadq *dp; 1125 1126 if (!dad_init) 1127 return; 1128 dp = nd6_dad_find(ifa); 1129 if (!dp) { 1130 /* DAD wasn't started yet */ 1131 return; 1132 } 1133 1134 nd6_dad_stoptimer(dp); 1135 1136 TAILQ_REMOVE(&dadq, (struct dadq *)dp, dad_list); 1137 free(dp, M_IP6NDP); 1138 dp = NULL; 1139 IFAFREE(ifa); 1140 } 1141 1142 static void 1143 nd6_dad_timer(ifa) 1144 struct ifaddr *ifa; 1145 { 1146 int s; 1147 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1148 struct dadq *dp; 1149 1150 s = splnet(); /* XXX */ 1151 1152 /* Sanity check */ 1153 if (ia == NULL) { 1154 log(LOG_ERR, "nd6_dad_timer: called with null parameter\n"); 1155 goto done; 1156 } 1157 dp = nd6_dad_find(ifa); 1158 if (dp == NULL) { 1159 log(LOG_ERR, "nd6_dad_timer: DAD structure not found\n"); 1160 goto done; 1161 } 1162 if (ia->ia6_flags & IN6_IFF_DUPLICATED) { 1163 log(LOG_ERR, "nd6_dad_timer: called with duplicated address " 1164 "%s(%s)\n", 1165 ip6_sprintf(&ia->ia_addr.sin6_addr), 1166 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1167 goto done; 1168 } 1169 if ((ia->ia6_flags & IN6_IFF_TENTATIVE) == 0) { 1170 log(LOG_ERR, "nd6_dad_timer: called with non-tentative address " 1171 "%s(%s)\n", 1172 ip6_sprintf(&ia->ia_addr.sin6_addr), 1173 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1174 goto done; 1175 } 1176 1177 /* timeouted with IFF_{RUNNING,UP} check */ 1178 if (dp->dad_ns_tcount > dad_maxtry) { 1179 nd6log((LOG_INFO, "%s: could not run DAD, driver problem?\n", 1180 if_name(ifa->ifa_ifp))); 1181 1182 TAILQ_REMOVE(&dadq, (struct dadq *)dp, dad_list); 1183 free(dp, M_IP6NDP); 1184 dp = NULL; 1185 IFAFREE(ifa); 1186 goto done; 1187 } 1188 1189 /* Need more checks? */ 1190 if (dp->dad_ns_ocount < dp->dad_count) { 1191 /* 1192 * We have more NS to go. Send NS packet for DAD. 1193 */ 1194 nd6_dad_ns_output(dp, ifa); 1195 nd6_dad_starttimer(dp, 1196 nd_ifinfo[ifa->ifa_ifp->if_index].retrans * hz / 1000); 1197 } else { 1198 /* 1199 * We have transmitted sufficient number of DAD packets. 1200 * See what we've got. 1201 */ 1202 int duplicate; 1203 1204 duplicate = 0; 1205 1206 if (dp->dad_na_icount) { 1207 /* 1208 * the check is in nd6_dad_na_input(), 1209 * but just in case 1210 */ 1211 duplicate++; 1212 } 1213 1214 if (dp->dad_ns_icount) { 1215 #if 0 /* heuristics */ 1216 /* 1217 * if 1218 * - we have sent many(?) DAD NS, and 1219 * - the number of NS we sent equals to the 1220 * number of NS we've got, and 1221 * - we've got no NA 1222 * we may have a faulty network card/driver which 1223 * loops back multicasts to myself. 1224 */ 1225 if (3 < dp->dad_count 1226 && dp->dad_ns_icount == dp->dad_count 1227 && dp->dad_na_icount == 0) { 1228 log(LOG_INFO, "DAD questionable for %s(%s): " 1229 "network card loops back multicast?\n", 1230 ip6_sprintf(&ia->ia_addr.sin6_addr), 1231 if_name(ifa->ifa_ifp)); 1232 /* XXX consider it a duplicate or not? */ 1233 /* duplicate++; */ 1234 } else { 1235 /* We've seen NS, means DAD has failed. */ 1236 duplicate++; 1237 } 1238 #else 1239 /* We've seen NS, means DAD has failed. */ 1240 duplicate++; 1241 #endif 1242 } 1243 1244 if (duplicate) { 1245 /* (*dp) will be freed in nd6_dad_duplicated() */ 1246 dp = NULL; 1247 nd6_dad_duplicated(ifa); 1248 } else { 1249 /* 1250 * We are done with DAD. No NA came, no NS came. 1251 * duplicated address found. 1252 */ 1253 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1254 1255 nd6log((LOG_DEBUG, 1256 "%s: DAD complete for %s - no duplicates found\n", 1257 if_name(ifa->ifa_ifp), 1258 ip6_sprintf(&ia->ia_addr.sin6_addr))); 1259 1260 TAILQ_REMOVE(&dadq, (struct dadq *)dp, dad_list); 1261 free(dp, M_IP6NDP); 1262 dp = NULL; 1263 IFAFREE(ifa); 1264 } 1265 } 1266 1267 done: 1268 splx(s); 1269 } 1270 1271 void 1272 nd6_dad_duplicated(ifa) 1273 struct ifaddr *ifa; 1274 { 1275 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1276 struct dadq *dp; 1277 1278 dp = nd6_dad_find(ifa); 1279 if (dp == NULL) { 1280 log(LOG_ERR, "nd6_dad_duplicated: DAD structure not found\n"); 1281 return; 1282 } 1283 1284 log(LOG_ERR, "%s: DAD detected duplicate IPv6 address %s: " 1285 "NS in/out=%d/%d, NA in=%d\n", 1286 if_name(ifa->ifa_ifp), ip6_sprintf(&ia->ia_addr.sin6_addr), 1287 dp->dad_ns_icount, dp->dad_ns_ocount, dp->dad_na_icount); 1288 1289 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1290 ia->ia6_flags |= IN6_IFF_DUPLICATED; 1291 1292 /* We are done with DAD, with duplicated address found. (failure) */ 1293 nd6_dad_stoptimer(dp); 1294 1295 log(LOG_ERR, "%s: DAD complete for %s - duplicate found\n", 1296 if_name(ifa->ifa_ifp), ip6_sprintf(&ia->ia_addr.sin6_addr)); 1297 log(LOG_ERR, "%s: manual intervention required\n", 1298 if_name(ifa->ifa_ifp)); 1299 1300 TAILQ_REMOVE(&dadq, (struct dadq *)dp, dad_list); 1301 free(dp, M_IP6NDP); 1302 dp = NULL; 1303 IFAFREE(ifa); 1304 } 1305 1306 static void 1307 nd6_dad_ns_output(dp, ifa) 1308 struct dadq *dp; 1309 struct ifaddr *ifa; 1310 { 1311 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1312 struct ifnet *ifp = ifa->ifa_ifp; 1313 1314 dp->dad_ns_tcount++; 1315 if ((ifp->if_flags & IFF_UP) == 0) { 1316 #if 0 1317 printf("%s: interface down?\n", if_name(ifp)); 1318 #endif 1319 return; 1320 } 1321 if ((ifp->if_flags & IFF_RUNNING) == 0) { 1322 #if 0 1323 printf("%s: interface not running?\n", if_name(ifp)); 1324 #endif 1325 return; 1326 } 1327 1328 dp->dad_ns_ocount++; 1329 nd6_ns_output(ifp, NULL, &ia->ia_addr.sin6_addr, NULL, 1); 1330 } 1331 1332 static void 1333 nd6_dad_ns_input(ifa) 1334 struct ifaddr *ifa; 1335 { 1336 struct in6_ifaddr *ia; 1337 struct ifnet *ifp; 1338 const struct in6_addr *taddr6; 1339 struct dadq *dp; 1340 int duplicate; 1341 1342 if (!ifa) 1343 panic("ifa == NULL in nd6_dad_ns_input"); 1344 1345 ia = (struct in6_ifaddr *)ifa; 1346 ifp = ifa->ifa_ifp; 1347 taddr6 = &ia->ia_addr.sin6_addr; 1348 duplicate = 0; 1349 dp = nd6_dad_find(ifa); 1350 1351 /* Quickhack - completely ignore DAD NS packets */ 1352 if (dad_ignore_ns) { 1353 nd6log((LOG_INFO, 1354 "nd6_dad_ns_input: ignoring DAD NS packet for " 1355 "address %s(%s)\n", ip6_sprintf(taddr6), 1356 if_name(ifa->ifa_ifp))); 1357 return; 1358 } 1359 1360 /* 1361 * if I'm yet to start DAD, someone else started using this address 1362 * first. I have a duplicate and you win. 1363 */ 1364 if (!dp || dp->dad_ns_ocount == 0) 1365 duplicate++; 1366 1367 /* XXX more checks for loopback situation - see nd6_dad_timer too */ 1368 1369 if (duplicate) { 1370 dp = NULL; /* will be freed in nd6_dad_duplicated() */ 1371 nd6_dad_duplicated(ifa); 1372 } else { 1373 /* 1374 * not sure if I got a duplicate. 1375 * increment ns count and see what happens. 1376 */ 1377 if (dp) 1378 dp->dad_ns_icount++; 1379 } 1380 } 1381 1382 static void 1383 nd6_dad_na_input(ifa) 1384 struct ifaddr *ifa; 1385 { 1386 struct dadq *dp; 1387 1388 if (!ifa) 1389 panic("ifa == NULL in nd6_dad_na_input"); 1390 1391 dp = nd6_dad_find(ifa); 1392 if (dp) 1393 dp->dad_na_icount++; 1394 1395 /* remove the address. */ 1396 nd6_dad_duplicated(ifa); 1397 } 1398