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 an 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 an 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 #ifdef IPSEC 508 /* Don't lookup socket */ 509 (void)ipsec_setsocket(m, NULL); 510 #endif 511 ip6_output(m, NULL, NULL, dad ? IPV6_DADOUTPUT : 0, &im6o, &outif); 512 if (outif) { 513 icmp6_ifstat_inc(outif, ifs6_out_msg); 514 icmp6_ifstat_inc(outif, ifs6_out_neighborsolicit); 515 } 516 icmp6stat.icp6s_outhist[ND_NEIGHBOR_SOLICIT]++; 517 } 518 519 /* 520 * Neighbor advertisement input handling. 521 * 522 * Based on RFC 2461 523 * Based on RFC 2462 (duplicated address detection) 524 * 525 * the following items are not implemented yet: 526 * - proxy advertisement delay rule (RFC2461 7.2.8, last paragraph, SHOULD) 527 * - anycast advertisement delay rule (RFC2461 7.2.7, SHOULD) 528 */ 529 void 530 nd6_na_input(m, off, icmp6len) 531 struct mbuf *m; 532 int off, icmp6len; 533 { 534 struct ifnet *ifp = m->m_pkthdr.rcvif; 535 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 536 struct nd_neighbor_advert *nd_na; 537 #if 0 538 struct in6_addr saddr6 = ip6->ip6_src; 539 #endif 540 struct in6_addr daddr6 = ip6->ip6_dst; 541 struct in6_addr taddr6; 542 int flags; 543 int is_router; 544 int is_solicited; 545 int is_override; 546 char *lladdr = NULL; 547 int lladdrlen = 0; 548 struct ifaddr *ifa; 549 struct llinfo_nd6 *ln; 550 struct rtentry *rt; 551 struct sockaddr_dl *sdl; 552 union nd_opts ndopts; 553 554 if (ip6->ip6_hlim != 255) { 555 nd6log((LOG_ERR, 556 "nd6_na_input: invalid hlim (%d) from %s to %s on %s\n", 557 ip6->ip6_hlim, ip6_sprintf(&ip6->ip6_src), 558 ip6_sprintf(&ip6->ip6_dst), if_name(ifp))); 559 goto bad; 560 } 561 562 #ifndef PULLDOWN_TEST 563 IP6_EXTHDR_CHECK(m, off, icmp6len,); 564 nd_na = (struct nd_neighbor_advert *)((caddr_t)ip6 + off); 565 #else 566 IP6_EXTHDR_GET(nd_na, struct nd_neighbor_advert *, m, off, icmp6len); 567 if (nd_na == NULL) { 568 icmp6stat.icp6s_tooshort++; 569 return; 570 } 571 #endif 572 taddr6 = nd_na->nd_na_target; 573 flags = nd_na->nd_na_flags_reserved; 574 is_router = ((flags & ND_NA_FLAG_ROUTER) != 0); 575 is_solicited = ((flags & ND_NA_FLAG_SOLICITED) != 0); 576 is_override = ((flags & ND_NA_FLAG_OVERRIDE) != 0); 577 578 if (IN6_IS_SCOPE_LINKLOCAL(&taddr6)) 579 taddr6.s6_addr16[1] = htons(ifp->if_index); 580 581 if (IN6_IS_ADDR_MULTICAST(&taddr6)) { 582 nd6log((LOG_ERR, 583 "nd6_na_input: invalid target address %s\n", 584 ip6_sprintf(&taddr6))); 585 goto bad; 586 } 587 if (IN6_IS_ADDR_MULTICAST(&daddr6)) 588 if (is_solicited) { 589 nd6log((LOG_ERR, 590 "nd6_na_input: a solicited adv is multicasted\n")); 591 goto bad; 592 } 593 594 icmp6len -= sizeof(*nd_na); 595 nd6_option_init(nd_na + 1, icmp6len, &ndopts); 596 if (nd6_options(&ndopts) < 0) { 597 nd6log((LOG_INFO, 598 "nd6_na_input: invalid ND option, ignored\n")); 599 /* nd6_options have incremented stats */ 600 goto freeit; 601 } 602 603 if (ndopts.nd_opts_tgt_lladdr) { 604 lladdr = (char *)(ndopts.nd_opts_tgt_lladdr + 1); 605 lladdrlen = ndopts.nd_opts_tgt_lladdr->nd_opt_len << 3; 606 } 607 608 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &taddr6); 609 610 /* 611 * Target address matches one of my interface address. 612 * 613 * If my address is tentative, this means that there's somebody 614 * already using the same address as mine. This indicates DAD failure. 615 * This is defined in RFC 2462. 616 * 617 * Otherwise, process as defined in RFC 2461. 618 */ 619 if (ifa 620 && (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_TENTATIVE)) { 621 nd6_dad_na_input(ifa); 622 goto freeit; 623 } 624 625 /* Just for safety, maybe unnecessary. */ 626 if (ifa) { 627 log(LOG_ERR, 628 "nd6_na_input: duplicate IP6 address %s\n", 629 ip6_sprintf(&taddr6)); 630 goto freeit; 631 } 632 633 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) { 634 nd6log((LOG_INFO, 635 "nd6_na_input: lladdrlen mismatch for %s " 636 "(if %d, NA packet %d)\n", 637 ip6_sprintf(&taddr6), ifp->if_addrlen, lladdrlen - 2)); 638 goto bad; 639 } 640 641 /* 642 * If no neighbor cache entry is found, NA SHOULD silently be discarded. 643 */ 644 rt = nd6_lookup(&taddr6, 0, ifp); 645 if ((rt == NULL) || 646 ((ln = (struct llinfo_nd6 *)rt->rt_llinfo) == NULL) || 647 ((sdl = SDL(rt->rt_gateway)) == NULL)) 648 goto freeit; 649 650 if (ln->ln_state == ND6_LLINFO_INCOMPLETE) { 651 /* 652 * If the link-layer has address, and no lladdr option came, 653 * discard the packet. 654 */ 655 if (ifp->if_addrlen && !lladdr) 656 goto freeit; 657 658 /* 659 * Record link-layer address, and update the state. 660 */ 661 sdl->sdl_alen = ifp->if_addrlen; 662 bcopy(lladdr, LLADDR(sdl), ifp->if_addrlen); 663 if (is_solicited) { 664 ln->ln_state = ND6_LLINFO_REACHABLE; 665 ln->ln_byhint = 0; 666 if (ln->ln_expire) 667 ln->ln_expire = time_second + 668 nd_ifinfo[rt->rt_ifp->if_index].reachable; 669 } else { 670 ln->ln_state = ND6_LLINFO_STALE; 671 ln->ln_expire = time_second + nd6_gctimer; 672 } 673 if ((ln->ln_router = is_router) != 0) { 674 /* 675 * This means a router's state has changed from 676 * non-reachable to probably reachable, and might 677 * affect the status of associated prefixes.. 678 */ 679 pfxlist_onlink_check(); 680 } 681 } else { 682 int llchange; 683 684 /* 685 * Check if the link-layer address has changed or not. 686 */ 687 if (!lladdr) 688 llchange = 0; 689 else { 690 if (sdl->sdl_alen) { 691 if (bcmp(lladdr, LLADDR(sdl), ifp->if_addrlen)) 692 llchange = 1; 693 else 694 llchange = 0; 695 } else 696 llchange = 1; 697 } 698 699 /* 700 * This is VERY complex. Look at it with care. 701 * 702 * override solicit lladdr llchange action 703 * (L: record lladdr) 704 * 705 * 0 0 n -- (2c) 706 * 0 0 y n (2b) L 707 * 0 0 y y (1) REACHABLE->STALE 708 * 0 1 n -- (2c) *->REACHABLE 709 * 0 1 y n (2b) L *->REACHABLE 710 * 0 1 y y (1) REACHABLE->STALE 711 * 1 0 n -- (2a) 712 * 1 0 y n (2a) L 713 * 1 0 y y (2a) L *->STALE 714 * 1 1 n -- (2a) *->REACHABLE 715 * 1 1 y n (2a) L *->REACHABLE 716 * 1 1 y y (2a) L *->REACHABLE 717 */ 718 if (!is_override && (lladdr && llchange)) { /* (1) */ 719 /* 720 * If state is REACHABLE, make it STALE. 721 * no other updates should be done. 722 */ 723 if (ln->ln_state == ND6_LLINFO_REACHABLE) { 724 ln->ln_state = ND6_LLINFO_STALE; 725 ln->ln_expire = time_second + nd6_gctimer; 726 } 727 goto freeit; 728 } else if (is_override /* (2a) */ 729 || (!is_override && (lladdr && !llchange)) /* (2b) */ 730 || !lladdr) { /* (2c) */ 731 /* 732 * Update link-local address, if any. 733 */ 734 if (lladdr) { 735 sdl->sdl_alen = ifp->if_addrlen; 736 bcopy(lladdr, LLADDR(sdl), ifp->if_addrlen); 737 } 738 739 /* 740 * If solicited, make the state REACHABLE. 741 * If not solicited and the link-layer address was 742 * changed, make it STALE. 743 */ 744 if (is_solicited) { 745 ln->ln_state = ND6_LLINFO_REACHABLE; 746 ln->ln_byhint = 0; 747 if (ln->ln_expire) { 748 ln->ln_expire = time_second + 749 nd_ifinfo[ifp->if_index].reachable; 750 } 751 } else { 752 if (lladdr && llchange) { 753 ln->ln_state = ND6_LLINFO_STALE; 754 ln->ln_expire = time_second + nd6_gctimer; 755 } 756 } 757 } 758 759 if (ln->ln_router && !is_router) { 760 /* 761 * The peer dropped the router flag. 762 * Remove the sender from the Default Router List and 763 * update the Destination Cache entries. 764 */ 765 struct nd_defrouter *dr; 766 struct in6_addr *in6; 767 int s; 768 769 in6 = &((struct sockaddr_in6 *)rt_key(rt))->sin6_addr; 770 771 /* 772 * Lock to protect the default router list. 773 * XXX: this might be unnecessary, since this function 774 * is only called under the network software interrupt 775 * context. However, we keep it just for safety. 776 */ 777 s = splnet(); 778 dr = defrouter_lookup(in6, rt->rt_ifp); 779 if (dr) 780 defrtrlist_del(dr); 781 else if (!ip6_forwarding && ip6_accept_rtadv) { 782 /* 783 * Even if the neighbor is not in the default 784 * router list, the neighbor may be used 785 * as a next hop for some destinations 786 * (e.g. redirect case). So we must 787 * call rt6_flush explicitly. 788 */ 789 rt6_flush(&ip6->ip6_src, rt->rt_ifp); 790 } 791 splx(s); 792 } 793 ln->ln_router = is_router; 794 } 795 rt->rt_flags &= ~RTF_REJECT; 796 ln->ln_asked = 0; 797 if (ln->ln_hold) { 798 /* 799 * we assume ifp is not a loopback here, so just set the 2nd 800 * argument as the 1st one. 801 */ 802 nd6_output(ifp, ifp, ln->ln_hold, 803 (struct sockaddr_in6 *)rt_key(rt), rt); 804 ln->ln_hold = 0; 805 } 806 807 freeit: 808 m_freem(m); 809 return; 810 811 bad: 812 icmp6stat.icp6s_badna++; 813 m_freem(m); 814 } 815 816 /* 817 * Neighbor advertisement output handling. 818 * 819 * Based on RFC 2461 820 * 821 * the following items are not implemented yet: 822 * - proxy advertisement delay rule (RFC2461 7.2.8, last paragraph, SHOULD) 823 * - anycast advertisement delay rule (RFC2461 7.2.7, SHOULD) 824 */ 825 void 826 nd6_na_output(ifp, daddr6, taddr6, flags, tlladdr, sdl0) 827 struct ifnet *ifp; 828 const struct in6_addr *daddr6, *taddr6; 829 u_long flags; 830 int tlladdr; /* 1 if include target link-layer address */ 831 struct sockaddr *sdl0; /* sockaddr_dl (= proxy NA) or NULL */ 832 { 833 struct mbuf *m; 834 struct ip6_hdr *ip6; 835 struct nd_neighbor_advert *nd_na; 836 struct in6_ifaddr *ia = NULL; 837 struct ip6_moptions im6o; 838 int icmp6len; 839 int maxlen; 840 caddr_t mac = NULL; 841 struct ifnet *outif = NULL; 842 843 /* estimate the size of message */ 844 maxlen = sizeof(*ip6) + sizeof(*nd_na); 845 maxlen += (sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7; 846 if (max_linkhdr + maxlen >= MCLBYTES) { 847 #ifdef DIAGNOSTIC 848 printf("nd6_na_output: max_linkhdr + maxlen >= MCLBYTES " 849 "(%d + %d > %d)\n", max_linkhdr, maxlen, MCLBYTES); 850 #endif 851 return; 852 } 853 854 MGETHDR(m, M_DONTWAIT, MT_DATA); 855 if (m && max_linkhdr + maxlen >= MHLEN) { 856 MCLGET(m, M_DONTWAIT); 857 if ((m->m_flags & M_EXT) == 0) { 858 m_free(m); 859 m = NULL; 860 } 861 } 862 if (m == NULL) 863 return; 864 m->m_pkthdr.rcvif = NULL; 865 866 if (IN6_IS_ADDR_MULTICAST(daddr6)) { 867 m->m_flags |= M_MCAST; 868 im6o.im6o_multicast_ifp = ifp; 869 im6o.im6o_multicast_hlim = 255; 870 im6o.im6o_multicast_loop = 0; 871 } 872 873 icmp6len = sizeof(*nd_na); 874 m->m_pkthdr.len = m->m_len = sizeof(struct ip6_hdr) + icmp6len; 875 m->m_data += max_linkhdr; /* or MH_ALIGN() equivalent? */ 876 877 /* fill neighbor advertisement packet */ 878 ip6 = mtod(m, struct ip6_hdr *); 879 ip6->ip6_flow = 0; 880 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 881 ip6->ip6_vfc |= IPV6_VERSION; 882 ip6->ip6_nxt = IPPROTO_ICMPV6; 883 ip6->ip6_hlim = 255; 884 if (IN6_IS_ADDR_UNSPECIFIED(daddr6)) { 885 /* reply to DAD */ 886 ip6->ip6_dst.s6_addr16[0] = IPV6_ADDR_INT16_MLL; 887 ip6->ip6_dst.s6_addr16[1] = htons(ifp->if_index); 888 ip6->ip6_dst.s6_addr32[1] = 0; 889 ip6->ip6_dst.s6_addr32[2] = 0; 890 ip6->ip6_dst.s6_addr32[3] = IPV6_ADDR_INT32_ONE; 891 flags &= ~ND_NA_FLAG_SOLICITED; 892 } else 893 ip6->ip6_dst = *daddr6; 894 895 /* 896 * Select a source whose scope is the same as that of the dest. 897 */ 898 ia = in6_ifawithifp(ifp, &ip6->ip6_dst); 899 if (ia == NULL) { 900 m_freem(m); 901 return; 902 } 903 ip6->ip6_src = ia->ia_addr.sin6_addr; 904 nd_na = (struct nd_neighbor_advert *)(ip6 + 1); 905 nd_na->nd_na_type = ND_NEIGHBOR_ADVERT; 906 nd_na->nd_na_code = 0; 907 nd_na->nd_na_target = *taddr6; 908 if (IN6_IS_SCOPE_LINKLOCAL(&nd_na->nd_na_target)) 909 nd_na->nd_na_target.s6_addr16[1] = 0; 910 911 /* 912 * "tlladdr" indicates NS's condition for adding tlladdr or not. 913 * see nd6_ns_input() for details. 914 * Basically, if NS packet is sent to unicast/anycast addr, 915 * target lladdr option SHOULD NOT be included. 916 */ 917 if (tlladdr) { 918 /* 919 * sdl0 != NULL indicates proxy NA. If we do proxy, use 920 * lladdr in sdl0. If we are not proxying (sending NA for 921 * my address) use lladdr configured for the interface. 922 */ 923 if (sdl0 == NULL) 924 mac = nd6_ifptomac(ifp); 925 else if (sdl0->sa_family == AF_LINK) { 926 struct sockaddr_dl *sdl; 927 sdl = (struct sockaddr_dl *)sdl0; 928 if (sdl->sdl_alen == ifp->if_addrlen) 929 mac = LLADDR(sdl); 930 } 931 } 932 if (tlladdr && mac) { 933 int optlen = sizeof(struct nd_opt_hdr) + ifp->if_addrlen; 934 struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)(nd_na + 1); 935 936 /* roundup to 8 bytes alignment! */ 937 optlen = (optlen + 7) & ~7; 938 939 m->m_pkthdr.len += optlen; 940 m->m_len += optlen; 941 icmp6len += optlen; 942 bzero((caddr_t)nd_opt, optlen); 943 nd_opt->nd_opt_type = ND_OPT_TARGET_LINKADDR; 944 nd_opt->nd_opt_len = optlen >> 3; 945 bcopy(mac, (caddr_t)(nd_opt + 1), ifp->if_addrlen); 946 } else 947 flags &= ~ND_NA_FLAG_OVERRIDE; 948 949 ip6->ip6_plen = htons((u_short)icmp6len); 950 nd_na->nd_na_flags_reserved = flags; 951 nd_na->nd_na_cksum = 0; 952 nd_na->nd_na_cksum = 953 in6_cksum(m, IPPROTO_ICMPV6, sizeof(struct ip6_hdr), icmp6len); 954 955 #ifdef IPSEC 956 /* Don't lookup socket */ 957 (void)ipsec_setsocket(m, NULL); 958 #endif 959 ip6_output(m, NULL, NULL, 0, &im6o, &outif); 960 if (outif) { 961 icmp6_ifstat_inc(outif, ifs6_out_msg); 962 icmp6_ifstat_inc(outif, ifs6_out_neighboradvert); 963 } 964 icmp6stat.icp6s_outhist[ND_NEIGHBOR_ADVERT]++; 965 } 966 967 caddr_t 968 nd6_ifptomac(ifp) 969 struct ifnet *ifp; 970 { 971 switch (ifp->if_type) { 972 case IFT_ARCNET: 973 case IFT_ETHER: 974 case IFT_FDDI: 975 case IFT_IEEE1394: 976 #ifdef IFT_L2VLAN 977 case IFT_L2VLAN: 978 #endif 979 #ifdef IFT_IEEE80211 980 case IFT_IEEE80211: 981 #endif 982 return ((caddr_t)(ifp + 1)); 983 break; 984 default: 985 return NULL; 986 } 987 } 988 989 TAILQ_HEAD(dadq_head, dadq); 990 struct dadq { 991 TAILQ_ENTRY(dadq) dad_list; 992 struct ifaddr *dad_ifa; 993 int dad_count; /* max NS to send */ 994 int dad_ns_tcount; /* # of trials to send NS */ 995 int dad_ns_ocount; /* NS sent so far */ 996 int dad_ns_icount; 997 int dad_na_icount; 998 struct callout dad_timer_ch; 999 }; 1000 1001 static struct dadq_head dadq; 1002 static int dad_init = 0; 1003 1004 static struct dadq * 1005 nd6_dad_find(ifa) 1006 struct ifaddr *ifa; 1007 { 1008 struct dadq *dp; 1009 1010 for (dp = dadq.tqh_first; dp; dp = dp->dad_list.tqe_next) { 1011 if (dp->dad_ifa == ifa) 1012 return dp; 1013 } 1014 return NULL; 1015 } 1016 1017 static void 1018 nd6_dad_starttimer(dp, ticks) 1019 struct dadq *dp; 1020 int ticks; 1021 { 1022 1023 callout_reset(&dp->dad_timer_ch, ticks, 1024 (void (*) __P((void *)))nd6_dad_timer, (void *)dp->dad_ifa); 1025 } 1026 1027 static void 1028 nd6_dad_stoptimer(dp) 1029 struct dadq *dp; 1030 { 1031 1032 callout_stop(&dp->dad_timer_ch); 1033 } 1034 1035 /* 1036 * Start Duplicated Address Detection (DAD) for specified interface address. 1037 */ 1038 void 1039 nd6_dad_start(ifa, tick) 1040 struct ifaddr *ifa; 1041 int *tick; /* minimum delay ticks for IFF_UP event */ 1042 { 1043 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1044 struct dadq *dp; 1045 1046 if (!dad_init) { 1047 TAILQ_INIT(&dadq); 1048 dad_init++; 1049 } 1050 1051 /* 1052 * If we don't need DAD, don't do it. 1053 * There are several cases: 1054 * - DAD is disabled (ip6_dad_count == 0) 1055 * - the interface address is anycast 1056 */ 1057 if (!(ia->ia6_flags & IN6_IFF_TENTATIVE)) { 1058 log(LOG_DEBUG, 1059 "nd6_dad_start: called with non-tentative address " 1060 "%s(%s)\n", 1061 ip6_sprintf(&ia->ia_addr.sin6_addr), 1062 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1063 return; 1064 } 1065 if (ia->ia6_flags & IN6_IFF_ANYCAST) { 1066 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1067 return; 1068 } 1069 if (!ip6_dad_count) { 1070 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1071 return; 1072 } 1073 if (!ifa->ifa_ifp) 1074 panic("nd6_dad_start: ifa->ifa_ifp == NULL"); 1075 if (!(ifa->ifa_ifp->if_flags & IFF_UP)) 1076 return; 1077 if (nd6_dad_find(ifa) != NULL) { 1078 /* DAD already in progress */ 1079 return; 1080 } 1081 1082 dp = malloc(sizeof(*dp), M_IP6NDP, M_NOWAIT); 1083 if (dp == NULL) { 1084 log(LOG_ERR, "nd6_dad_start: memory allocation failed for " 1085 "%s(%s)\n", 1086 ip6_sprintf(&ia->ia_addr.sin6_addr), 1087 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1088 return; 1089 } 1090 bzero(dp, sizeof(*dp)); 1091 callout_init(&dp->dad_timer_ch, 0); 1092 TAILQ_INSERT_TAIL(&dadq, (struct dadq *)dp, dad_list); 1093 1094 nd6log((LOG_DEBUG, "%s: starting DAD for %s\n", if_name(ifa->ifa_ifp), 1095 ip6_sprintf(&ia->ia_addr.sin6_addr))); 1096 1097 /* 1098 * Send NS packet for DAD, ip6_dad_count times. 1099 * Note that we must delay the first transmission, if this is the 1100 * first packet to be sent from the interface after interface 1101 * (re)initialization. 1102 */ 1103 dp->dad_ifa = ifa; 1104 IFAREF(ifa); /* just for safety */ 1105 dp->dad_count = ip6_dad_count; 1106 dp->dad_ns_icount = dp->dad_na_icount = 0; 1107 dp->dad_ns_ocount = dp->dad_ns_tcount = 0; 1108 if (tick == NULL) { 1109 nd6_dad_ns_output(dp, ifa); 1110 nd6_dad_starttimer(dp, 1111 nd_ifinfo[ifa->ifa_ifp->if_index].retrans * hz / 1000); 1112 } else { 1113 int ntick; 1114 1115 if (*tick == 0) 1116 ntick = random() % (MAX_RTR_SOLICITATION_DELAY * hz); 1117 else 1118 ntick = *tick + random() % (hz / 2); 1119 *tick = ntick; 1120 nd6_dad_starttimer(dp, ntick); 1121 } 1122 } 1123 1124 /* 1125 * terminate DAD unconditionally. used for address removals. 1126 */ 1127 void 1128 nd6_dad_stop(ifa) 1129 struct ifaddr *ifa; 1130 { 1131 struct dadq *dp; 1132 1133 if (!dad_init) 1134 return; 1135 dp = nd6_dad_find(ifa); 1136 if (!dp) { 1137 /* DAD wasn't started yet */ 1138 return; 1139 } 1140 1141 nd6_dad_stoptimer(dp); 1142 1143 TAILQ_REMOVE(&dadq, (struct dadq *)dp, dad_list); 1144 free(dp, M_IP6NDP); 1145 dp = NULL; 1146 IFAFREE(ifa); 1147 } 1148 1149 static void 1150 nd6_dad_timer(ifa) 1151 struct ifaddr *ifa; 1152 { 1153 int s; 1154 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1155 struct dadq *dp; 1156 1157 s = splnet(); /* XXX */ 1158 1159 /* Sanity check */ 1160 if (ia == NULL) { 1161 log(LOG_ERR, "nd6_dad_timer: called with null parameter\n"); 1162 goto done; 1163 } 1164 dp = nd6_dad_find(ifa); 1165 if (dp == NULL) { 1166 log(LOG_ERR, "nd6_dad_timer: DAD structure not found\n"); 1167 goto done; 1168 } 1169 if (ia->ia6_flags & IN6_IFF_DUPLICATED) { 1170 log(LOG_ERR, "nd6_dad_timer: called with duplicated 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 if ((ia->ia6_flags & IN6_IFF_TENTATIVE) == 0) { 1177 log(LOG_ERR, "nd6_dad_timer: called with non-tentative address " 1178 "%s(%s)\n", 1179 ip6_sprintf(&ia->ia_addr.sin6_addr), 1180 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1181 goto done; 1182 } 1183 1184 /* timeouted with IFF_{RUNNING,UP} check */ 1185 if (dp->dad_ns_tcount > dad_maxtry) { 1186 nd6log((LOG_INFO, "%s: could not run DAD, driver problem?\n", 1187 if_name(ifa->ifa_ifp))); 1188 1189 TAILQ_REMOVE(&dadq, (struct dadq *)dp, dad_list); 1190 free(dp, M_IP6NDP); 1191 dp = NULL; 1192 IFAFREE(ifa); 1193 goto done; 1194 } 1195 1196 /* Need more checks? */ 1197 if (dp->dad_ns_ocount < dp->dad_count) { 1198 /* 1199 * We have more NS to go. Send NS packet for DAD. 1200 */ 1201 nd6_dad_ns_output(dp, ifa); 1202 nd6_dad_starttimer(dp, 1203 nd_ifinfo[ifa->ifa_ifp->if_index].retrans * hz / 1000); 1204 } else { 1205 /* 1206 * We have transmitted sufficient number of DAD packets. 1207 * See what we've got. 1208 */ 1209 int duplicate; 1210 1211 duplicate = 0; 1212 1213 if (dp->dad_na_icount) { 1214 /* 1215 * the check is in nd6_dad_na_input(), 1216 * but just in case 1217 */ 1218 duplicate++; 1219 } 1220 1221 if (dp->dad_ns_icount) { 1222 #if 0 /* heuristics */ 1223 /* 1224 * if 1225 * - we have sent many(?) DAD NS, and 1226 * - the number of NS we sent equals to the 1227 * number of NS we've got, and 1228 * - we've got no NA 1229 * we may have a faulty network card/driver which 1230 * loops back multicasts to myself. 1231 */ 1232 if (3 < dp->dad_count 1233 && dp->dad_ns_icount == dp->dad_count 1234 && dp->dad_na_icount == 0) { 1235 log(LOG_INFO, "DAD questionable for %s(%s): " 1236 "network card loops back multicast?\n", 1237 ip6_sprintf(&ia->ia_addr.sin6_addr), 1238 if_name(ifa->ifa_ifp)); 1239 /* XXX consider it a duplicate or not? */ 1240 /* duplicate++; */ 1241 } else { 1242 /* We've seen NS, means DAD has failed. */ 1243 duplicate++; 1244 } 1245 #else 1246 /* We've seen NS, means DAD has failed. */ 1247 duplicate++; 1248 #endif 1249 } 1250 1251 if (duplicate) { 1252 /* (*dp) will be freed in nd6_dad_duplicated() */ 1253 dp = NULL; 1254 nd6_dad_duplicated(ifa); 1255 } else { 1256 /* 1257 * We are done with DAD. No NA came, no NS came. 1258 * duplicated address found. 1259 */ 1260 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1261 1262 nd6log((LOG_DEBUG, 1263 "%s: DAD complete for %s - no duplicates found\n", 1264 if_name(ifa->ifa_ifp), 1265 ip6_sprintf(&ia->ia_addr.sin6_addr))); 1266 1267 TAILQ_REMOVE(&dadq, (struct dadq *)dp, dad_list); 1268 free(dp, M_IP6NDP); 1269 dp = NULL; 1270 IFAFREE(ifa); 1271 } 1272 } 1273 1274 done: 1275 splx(s); 1276 } 1277 1278 void 1279 nd6_dad_duplicated(ifa) 1280 struct ifaddr *ifa; 1281 { 1282 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1283 struct dadq *dp; 1284 1285 dp = nd6_dad_find(ifa); 1286 if (dp == NULL) { 1287 log(LOG_ERR, "nd6_dad_duplicated: DAD structure not found\n"); 1288 return; 1289 } 1290 1291 log(LOG_ERR, "%s: DAD detected duplicate IPv6 address %s: " 1292 "NS in/out=%d/%d, NA in=%d\n", 1293 if_name(ifa->ifa_ifp), ip6_sprintf(&ia->ia_addr.sin6_addr), 1294 dp->dad_ns_icount, dp->dad_ns_ocount, dp->dad_na_icount); 1295 1296 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1297 ia->ia6_flags |= IN6_IFF_DUPLICATED; 1298 1299 /* We are done with DAD, with duplicated address found. (failure) */ 1300 nd6_dad_stoptimer(dp); 1301 1302 log(LOG_ERR, "%s: DAD complete for %s - duplicate found\n", 1303 if_name(ifa->ifa_ifp), ip6_sprintf(&ia->ia_addr.sin6_addr)); 1304 log(LOG_ERR, "%s: manual intervention required\n", 1305 if_name(ifa->ifa_ifp)); 1306 1307 TAILQ_REMOVE(&dadq, (struct dadq *)dp, dad_list); 1308 free(dp, M_IP6NDP); 1309 dp = NULL; 1310 IFAFREE(ifa); 1311 } 1312 1313 static void 1314 nd6_dad_ns_output(dp, ifa) 1315 struct dadq *dp; 1316 struct ifaddr *ifa; 1317 { 1318 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1319 struct ifnet *ifp = ifa->ifa_ifp; 1320 1321 dp->dad_ns_tcount++; 1322 if ((ifp->if_flags & IFF_UP) == 0) { 1323 #if 0 1324 printf("%s: interface down?\n", if_name(ifp)); 1325 #endif 1326 return; 1327 } 1328 if ((ifp->if_flags & IFF_RUNNING) == 0) { 1329 #if 0 1330 printf("%s: interface not running?\n", if_name(ifp)); 1331 #endif 1332 return; 1333 } 1334 1335 dp->dad_ns_ocount++; 1336 nd6_ns_output(ifp, NULL, &ia->ia_addr.sin6_addr, NULL, 1); 1337 } 1338 1339 static void 1340 nd6_dad_ns_input(ifa) 1341 struct ifaddr *ifa; 1342 { 1343 struct in6_ifaddr *ia; 1344 struct ifnet *ifp; 1345 const struct in6_addr *taddr6; 1346 struct dadq *dp; 1347 int duplicate; 1348 1349 if (!ifa) 1350 panic("ifa == NULL in nd6_dad_ns_input"); 1351 1352 ia = (struct in6_ifaddr *)ifa; 1353 ifp = ifa->ifa_ifp; 1354 taddr6 = &ia->ia_addr.sin6_addr; 1355 duplicate = 0; 1356 dp = nd6_dad_find(ifa); 1357 1358 /* Quickhack - completely ignore DAD NS packets */ 1359 if (dad_ignore_ns) { 1360 nd6log((LOG_INFO, 1361 "nd6_dad_ns_input: ignoring DAD NS packet for " 1362 "address %s(%s)\n", ip6_sprintf(taddr6), 1363 if_name(ifa->ifa_ifp))); 1364 return; 1365 } 1366 1367 /* 1368 * if I'm yet to start DAD, someone else started using this address 1369 * first. I have a duplicate and you win. 1370 */ 1371 if (!dp || dp->dad_ns_ocount == 0) 1372 duplicate++; 1373 1374 /* XXX more checks for loopback situation - see nd6_dad_timer too */ 1375 1376 if (duplicate) { 1377 dp = NULL; /* will be freed in nd6_dad_duplicated() */ 1378 nd6_dad_duplicated(ifa); 1379 } else { 1380 /* 1381 * not sure if I got a duplicate. 1382 * increment ns count and see what happens. 1383 */ 1384 if (dp) 1385 dp->dad_ns_icount++; 1386 } 1387 } 1388 1389 static void 1390 nd6_dad_na_input(ifa) 1391 struct ifaddr *ifa; 1392 { 1393 struct dadq *dp; 1394 1395 if (!ifa) 1396 panic("ifa == NULL in nd6_dad_na_input"); 1397 1398 dp = nd6_dad_find(ifa); 1399 if (dp) 1400 dp->dad_na_icount++; 1401 1402 /* remove the address. */ 1403 nd6_dad_duplicated(ifa); 1404 } 1405