1 /* $FreeBSD: src/sys/netinet6/nd6_nbr.c,v 1.4.2.6 2003/01/23 21:06:47 sam Exp $ */ 2 /* $DragonFly: src/sys/netinet6/nd6_nbr.c,v 1.18 2006/12/22 23:57:53 swildner Exp $ */ 3 /* $KAME: nd6_nbr.c,v 1.86 2002/01/21 02:33:04 jinmei Exp $ */ 4 5 /* 6 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project. 7 * All rights reserved. 8 * 9 * Redistribution and use in source and binary forms, with or without 10 * modification, are permitted provided that the following conditions 11 * are met: 12 * 1. Redistributions of source code must retain the above copyright 13 * notice, this list of conditions and the following disclaimer. 14 * 2. Redistributions in binary form must reproduce the above copyright 15 * notice, this list of conditions and the following disclaimer in the 16 * documentation and/or other materials provided with the distribution. 17 * 3. Neither the name of the project nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 */ 33 34 #include "opt_inet.h" 35 #include "opt_inet6.h" 36 #include "opt_ipsec.h" 37 38 #include <sys/param.h> 39 #include <sys/systm.h> 40 #include <sys/malloc.h> 41 #include <sys/mbuf.h> 42 #include <sys/socket.h> 43 #include <sys/sockio.h> 44 #include <sys/time.h> 45 #include <sys/kernel.h> 46 #include <sys/errno.h> 47 #include <sys/syslog.h> 48 #include <sys/queue.h> 49 #include <sys/callout.h> 50 #include <sys/thread2.h> 51 52 #include <net/if.h> 53 #include <net/if_types.h> 54 #include <net/if_dl.h> 55 #include <net/route.h> 56 57 #include <netinet/in.h> 58 #include <netinet/in_var.h> 59 #include <netinet6/in6_var.h> 60 #include <netinet/ip6.h> 61 #include <netinet6/ip6_var.h> 62 #include <netinet6/nd6.h> 63 #include <netinet/icmp6.h> 64 65 #ifdef IPSEC 66 #include <netinet6/ipsec.h> 67 #ifdef INET6 68 #include <netinet6/ipsec6.h> 69 #endif 70 #endif 71 72 #include <net/net_osdep.h> 73 74 #define SDL(s) ((struct sockaddr_dl *)s) 75 76 struct dadq; 77 static struct dadq *nd6_dad_find (struct ifaddr *); 78 static void nd6_dad_starttimer (struct dadq *, int); 79 static void nd6_dad_stoptimer (struct dadq *); 80 static void nd6_dad_timer (struct ifaddr *); 81 static void nd6_dad_ns_output (struct dadq *, struct ifaddr *); 82 static void nd6_dad_ns_input (struct ifaddr *); 83 static void nd6_dad_na_input (struct ifaddr *); 84 85 static int dad_ignore_ns = 0; /* ignore NS in DAD - specwise incorrect*/ 86 static int dad_maxtry = 15; /* max # of *tries* to transmit DAD packet */ 87 88 /* 89 * Input an Neighbor Solicitation Message. 90 * 91 * Based on RFC 2461 92 * Based on RFC 2462 (duplicated address detection) 93 */ 94 void 95 nd6_ns_input(struct mbuf *m, int off, int 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 = rtpurelookup((struct sockaddr *)&tsin6); 217 if (rt != NULL && (rt->rt_flags & RTF_ANNOUNCE) && 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 != NULL) 230 --rt->rt_refcnt; 231 } 232 if (ifa == NULL) { 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 = kin6addr_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(struct ifnet *ifp, const struct in6_addr *daddr6, 336 const struct in6_addr *taddr6, 337 struct llinfo_nd6 *ln, /* for source address determination */ 338 int dad) /* duplicated address detection */ 339 { 340 struct mbuf *m; 341 struct ip6_hdr *ip6; 342 struct nd_neighbor_solicit *nd_ns; 343 struct in6_ifaddr *ia = NULL; 344 struct ip6_moptions im6o; 345 int icmp6len; 346 int maxlen; 347 caddr_t mac; 348 struct ifnet *outif = NULL; 349 350 if (IN6_IS_ADDR_MULTICAST(taddr6)) 351 return; 352 353 /* estimate the size of message */ 354 maxlen = sizeof(*ip6) + sizeof(*nd_ns); 355 maxlen += (sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7; 356 if (max_linkhdr + maxlen >= MCLBYTES) { 357 #ifdef DIAGNOSTIC 358 kprintf("nd6_ns_output: max_linkhdr + maxlen >= MCLBYTES " 359 "(%d + %d > %d)\n", max_linkhdr, maxlen, MCLBYTES); 360 #endif 361 return; 362 } 363 364 m = m_getb(max_linkhdr + maxlen, MB_DONTWAIT, MT_DATA, M_PKTHDR); 365 if (m == NULL) 366 return; 367 368 if (daddr6 == NULL || IN6_IS_ADDR_MULTICAST(daddr6)) { 369 m->m_flags |= M_MCAST; 370 im6o.im6o_multicast_ifp = ifp; 371 im6o.im6o_multicast_hlim = 255; 372 im6o.im6o_multicast_loop = 0; 373 } 374 375 icmp6len = sizeof(*nd_ns); 376 m->m_pkthdr.len = m->m_len = sizeof(*ip6) + icmp6len; 377 m->m_data += max_linkhdr; /* or MH_ALIGN() equivalent? */ 378 379 /* fill neighbor solicitation packet */ 380 ip6 = mtod(m, struct ip6_hdr *); 381 ip6->ip6_flow = 0; 382 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 383 ip6->ip6_vfc |= IPV6_VERSION; 384 /* ip6->ip6_plen will be set later */ 385 ip6->ip6_nxt = IPPROTO_ICMPV6; 386 ip6->ip6_hlim = 255; 387 if (daddr6) 388 ip6->ip6_dst = *daddr6; 389 else { 390 ip6->ip6_dst.s6_addr16[0] = IPV6_ADDR_INT16_MLL; 391 ip6->ip6_dst.s6_addr16[1] = htons(ifp->if_index); 392 ip6->ip6_dst.s6_addr32[1] = 0; 393 ip6->ip6_dst.s6_addr32[2] = IPV6_ADDR_INT32_ONE; 394 ip6->ip6_dst.s6_addr32[3] = taddr6->s6_addr32[3]; 395 ip6->ip6_dst.s6_addr8[12] = 0xff; 396 } 397 if (!dad) { 398 #if 0 /* KAME way, exact address scope match */ 399 /* 400 * Select a source whose scope is the same as that of the dest. 401 * Typically, the dest is link-local solicitation multicast 402 * (i.e. neighbor discovery) or link-local/global unicast 403 * (i.e. neighbor un-reachability detection). 404 */ 405 ia = in6_ifawithifp(ifp, &ip6->ip6_dst); 406 if (ia == NULL) { 407 m_freem(m); 408 return; 409 } 410 ip6->ip6_src = ia->ia_addr.sin6_addr; 411 #else /* spec-wise correct */ 412 /* 413 * RFC2461 7.2.2: 414 * "If the source address of the packet prompting the 415 * solicitation is the same as one of the addresses assigned 416 * to the outgoing interface, that address SHOULD be placed 417 * in the IP Source Address of the outgoing solicitation. 418 * Otherwise, any one of the addresses assigned to the 419 * interface should be used." 420 * 421 * We use the source address for the prompting packet 422 * (saddr6), if: 423 * - saddr6 is given from the caller (by giving "ln"), and 424 * - saddr6 belongs to the outgoing interface. 425 * Otherwise, we perform a scope-wise match. 426 */ 427 struct ip6_hdr *hip6; /* hold ip6 */ 428 struct in6_addr *saddr6; 429 430 if (ln && ln->ln_hold) { 431 hip6 = mtod(ln->ln_hold, struct ip6_hdr *); 432 /* XXX pullup? */ 433 if (sizeof(*hip6) < ln->ln_hold->m_len) 434 saddr6 = &hip6->ip6_src; 435 else 436 saddr6 = NULL; 437 } else 438 saddr6 = NULL; 439 if (saddr6 && in6ifa_ifpwithaddr(ifp, saddr6)) 440 bcopy(saddr6, &ip6->ip6_src, sizeof(*saddr6)); 441 else { 442 ia = in6_ifawithifp(ifp, &ip6->ip6_dst); 443 if (ia == NULL) { 444 m_freem(m); 445 return; 446 } 447 ip6->ip6_src = ia->ia_addr.sin6_addr; 448 } 449 #endif 450 } else { 451 /* 452 * Source address for DAD packet must always be IPv6 453 * unspecified address. (0::0) 454 */ 455 bzero(&ip6->ip6_src, sizeof(ip6->ip6_src)); 456 } 457 nd_ns = (struct nd_neighbor_solicit *)(ip6 + 1); 458 nd_ns->nd_ns_type = ND_NEIGHBOR_SOLICIT; 459 nd_ns->nd_ns_code = 0; 460 nd_ns->nd_ns_reserved = 0; 461 nd_ns->nd_ns_target = *taddr6; 462 463 if (IN6_IS_SCOPE_LINKLOCAL(&nd_ns->nd_ns_target)) 464 nd_ns->nd_ns_target.s6_addr16[1] = 0; 465 466 /* 467 * Add source link-layer address option. 468 * 469 * spec implementation 470 * --- --- 471 * DAD packet MUST NOT do not add the option 472 * there's no link layer address: 473 * impossible do not add the option 474 * there's link layer address: 475 * Multicast NS MUST add one add the option 476 * Unicast NS SHOULD add one add the option 477 */ 478 if (!dad && (mac = nd6_ifptomac(ifp))) { 479 int optlen = sizeof(struct nd_opt_hdr) + ifp->if_addrlen; 480 struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)(nd_ns + 1); 481 /* 8 byte alignments... */ 482 optlen = (optlen + 7) & ~7; 483 484 m->m_pkthdr.len += optlen; 485 m->m_len += optlen; 486 icmp6len += optlen; 487 bzero((caddr_t)nd_opt, optlen); 488 nd_opt->nd_opt_type = ND_OPT_SOURCE_LINKADDR; 489 nd_opt->nd_opt_len = optlen >> 3; 490 bcopy(mac, (caddr_t)(nd_opt + 1), ifp->if_addrlen); 491 } 492 493 ip6->ip6_plen = htons((u_short)icmp6len); 494 nd_ns->nd_ns_cksum = 0; 495 nd_ns->nd_ns_cksum 496 = in6_cksum(m, IPPROTO_ICMPV6, sizeof(*ip6), icmp6len); 497 498 ip6_output(m, NULL, NULL, dad ? IPV6_DADOUTPUT : 0, &im6o, &outif, NULL); 499 if (outif) { 500 icmp6_ifstat_inc(outif, ifs6_out_msg); 501 icmp6_ifstat_inc(outif, ifs6_out_neighborsolicit); 502 } 503 icmp6stat.icp6s_outhist[ND_NEIGHBOR_SOLICIT]++; 504 } 505 506 /* 507 * Neighbor advertisement input handling. 508 * 509 * Based on RFC 2461 510 * Based on RFC 2462 (duplicated address detection) 511 * 512 * the following items are not implemented yet: 513 * - proxy advertisement delay rule (RFC2461 7.2.8, last paragraph, SHOULD) 514 * - anycast advertisement delay rule (RFC2461 7.2.7, SHOULD) 515 */ 516 void 517 nd6_na_input(struct mbuf *m, int off, int icmp6len) 518 { 519 struct ifnet *ifp = m->m_pkthdr.rcvif; 520 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 521 struct nd_neighbor_advert *nd_na; 522 #if 0 523 struct in6_addr saddr6 = ip6->ip6_src; 524 #endif 525 struct in6_addr daddr6 = ip6->ip6_dst; 526 struct in6_addr taddr6; 527 int flags; 528 int is_router; 529 int is_solicited; 530 int is_override; 531 char *lladdr = NULL; 532 int lladdrlen = 0; 533 struct ifaddr *ifa; 534 struct llinfo_nd6 *ln; 535 struct rtentry *rt; 536 struct sockaddr_dl *sdl; 537 union nd_opts ndopts; 538 539 if (ip6->ip6_hlim != 255) { 540 nd6log((LOG_ERR, 541 "nd6_na_input: invalid hlim (%d) from %s to %s on %s\n", 542 ip6->ip6_hlim, ip6_sprintf(&ip6->ip6_src), 543 ip6_sprintf(&ip6->ip6_dst), if_name(ifp))); 544 goto bad; 545 } 546 547 #ifndef PULLDOWN_TEST 548 IP6_EXTHDR_CHECK(m, off, icmp6len,); 549 nd_na = (struct nd_neighbor_advert *)((caddr_t)ip6 + off); 550 #else 551 IP6_EXTHDR_GET(nd_na, struct nd_neighbor_advert *, m, off, icmp6len); 552 if (nd_na == NULL) { 553 icmp6stat.icp6s_tooshort++; 554 return; 555 } 556 #endif 557 taddr6 = nd_na->nd_na_target; 558 flags = nd_na->nd_na_flags_reserved; 559 is_router = ((flags & ND_NA_FLAG_ROUTER) != 0); 560 is_solicited = ((flags & ND_NA_FLAG_SOLICITED) != 0); 561 is_override = ((flags & ND_NA_FLAG_OVERRIDE) != 0); 562 563 if (IN6_IS_SCOPE_LINKLOCAL(&taddr6)) 564 taddr6.s6_addr16[1] = htons(ifp->if_index); 565 566 if (IN6_IS_ADDR_MULTICAST(&taddr6)) { 567 nd6log((LOG_ERR, 568 "nd6_na_input: invalid target address %s\n", 569 ip6_sprintf(&taddr6))); 570 goto bad; 571 } 572 if (IN6_IS_ADDR_MULTICAST(&daddr6)) 573 if (is_solicited) { 574 nd6log((LOG_ERR, 575 "nd6_na_input: a solicited adv is multicasted\n")); 576 goto bad; 577 } 578 579 icmp6len -= sizeof(*nd_na); 580 nd6_option_init(nd_na + 1, icmp6len, &ndopts); 581 if (nd6_options(&ndopts) < 0) { 582 nd6log((LOG_INFO, 583 "nd6_na_input: invalid ND option, ignored\n")); 584 /* nd6_options have incremented stats */ 585 goto freeit; 586 } 587 588 if (ndopts.nd_opts_tgt_lladdr) { 589 lladdr = (char *)(ndopts.nd_opts_tgt_lladdr + 1); 590 lladdrlen = ndopts.nd_opts_tgt_lladdr->nd_opt_len << 3; 591 } 592 593 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &taddr6); 594 595 /* 596 * Target address matches one of my interface address. 597 * 598 * If my address is tentative, this means that there's somebody 599 * already using the same address as mine. This indicates DAD failure. 600 * This is defined in RFC 2462. 601 * 602 * Otherwise, process as defined in RFC 2461. 603 */ 604 if (ifa 605 && (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_TENTATIVE)) { 606 nd6_dad_na_input(ifa); 607 goto freeit; 608 } 609 610 /* Just for safety, maybe unnecessary. */ 611 if (ifa) { 612 log(LOG_ERR, 613 "nd6_na_input: duplicate IP6 address %s\n", 614 ip6_sprintf(&taddr6)); 615 goto freeit; 616 } 617 618 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) { 619 nd6log((LOG_INFO, 620 "nd6_na_input: lladdrlen mismatch for %s " 621 "(if %d, NA packet %d)\n", 622 ip6_sprintf(&taddr6), ifp->if_addrlen, lladdrlen - 2)); 623 goto bad; 624 } 625 626 /* 627 * If no neighbor cache entry is found, NA SHOULD silently be discarded. 628 */ 629 rt = nd6_lookup(&taddr6, 0, ifp); 630 if ((rt == NULL) || 631 ((ln = (struct llinfo_nd6 *)rt->rt_llinfo) == NULL) || 632 ((sdl = SDL(rt->rt_gateway)) == NULL)) 633 goto freeit; 634 635 if (ln->ln_state == ND6_LLINFO_INCOMPLETE) { 636 /* 637 * If the link-layer has address, and no lladdr option came, 638 * discard the packet. 639 */ 640 if (ifp->if_addrlen && !lladdr) 641 goto freeit; 642 643 /* 644 * Record link-layer address, and update the state. 645 */ 646 sdl->sdl_alen = ifp->if_addrlen; 647 bcopy(lladdr, LLADDR(sdl), ifp->if_addrlen); 648 if (is_solicited) { 649 ln->ln_state = ND6_LLINFO_REACHABLE; 650 ln->ln_byhint = 0; 651 if (ln->ln_expire) 652 ln->ln_expire = time_second + 653 ND_IFINFO(rt->rt_ifp)->reachable; 654 } else { 655 ln->ln_state = ND6_LLINFO_STALE; 656 ln->ln_expire = time_second + nd6_gctimer; 657 } 658 if ((ln->ln_router = is_router) != 0) { 659 /* 660 * This means a router's state has changed from 661 * non-reachable to probably reachable, and might 662 * affect the status of associated prefixes.. 663 */ 664 pfxlist_onlink_check(); 665 } 666 } else { 667 int llchange; 668 669 /* 670 * Check if the link-layer address has changed or not. 671 */ 672 if (!lladdr) 673 llchange = 0; 674 else { 675 if (sdl->sdl_alen) { 676 if (bcmp(lladdr, LLADDR(sdl), ifp->if_addrlen)) 677 llchange = 1; 678 else 679 llchange = 0; 680 } else 681 llchange = 1; 682 } 683 684 /* 685 * This is VERY complex. Look at it with care. 686 * 687 * override solicit lladdr llchange action 688 * (L: record lladdr) 689 * 690 * 0 0 n -- (2c) 691 * 0 0 y n (2b) L 692 * 0 0 y y (1) REACHABLE->STALE 693 * 0 1 n -- (2c) *->REACHABLE 694 * 0 1 y n (2b) L *->REACHABLE 695 * 0 1 y y (1) REACHABLE->STALE 696 * 1 0 n -- (2a) 697 * 1 0 y n (2a) L 698 * 1 0 y y (2a) L *->STALE 699 * 1 1 n -- (2a) *->REACHABLE 700 * 1 1 y n (2a) L *->REACHABLE 701 * 1 1 y y (2a) L *->REACHABLE 702 */ 703 if (!is_override && (lladdr && llchange)) { /* (1) */ 704 /* 705 * If state is REACHABLE, make it STALE. 706 * no other updates should be done. 707 */ 708 if (ln->ln_state == ND6_LLINFO_REACHABLE) { 709 ln->ln_state = ND6_LLINFO_STALE; 710 ln->ln_expire = time_second + nd6_gctimer; 711 } 712 goto freeit; 713 } else if (is_override /* (2a) */ 714 || (!is_override && (lladdr && !llchange)) /* (2b) */ 715 || !lladdr) { /* (2c) */ 716 /* 717 * Update link-local address, if any. 718 */ 719 if (lladdr) { 720 sdl->sdl_alen = ifp->if_addrlen; 721 bcopy(lladdr, LLADDR(sdl), ifp->if_addrlen); 722 } 723 724 /* 725 * If solicited, make the state REACHABLE. 726 * If not solicited and the link-layer address was 727 * changed, make it STALE. 728 */ 729 if (is_solicited) { 730 ln->ln_state = ND6_LLINFO_REACHABLE; 731 ln->ln_byhint = 0; 732 if (ln->ln_expire) { 733 ln->ln_expire = time_second + 734 ND_IFINFO(ifp)->reachable; 735 } 736 } else { 737 if (lladdr && llchange) { 738 ln->ln_state = ND6_LLINFO_STALE; 739 ln->ln_expire = time_second + nd6_gctimer; 740 } 741 } 742 } 743 744 if (ln->ln_router && !is_router) { 745 /* 746 * The peer dropped the router flag. 747 * Remove the sender from the Default Router List and 748 * update the Destination Cache entries. 749 */ 750 struct nd_defrouter *dr; 751 struct in6_addr *in6; 752 753 in6 = &((struct sockaddr_in6 *)rt_key(rt))->sin6_addr; 754 755 /* 756 * Lock to protect the default router list. 757 * XXX: this might be unnecessary, since this function 758 * is only called under the network software interrupt 759 * context. However, we keep it just for safety. 760 */ 761 crit_enter(); 762 dr = defrouter_lookup(in6, rt->rt_ifp); 763 if (dr) 764 defrtrlist_del(dr); 765 else if (!ip6_forwarding && ip6_accept_rtadv) { 766 /* 767 * Even if the neighbor is not in the default 768 * router list, the neighbor may be used 769 * as a next hop for some destinations 770 * (e.g. redirect case). So we must 771 * call rt6_flush explicitly. 772 */ 773 rt6_flush(&ip6->ip6_src, rt->rt_ifp); 774 } 775 crit_exit(); 776 } 777 ln->ln_router = is_router; 778 } 779 rt->rt_flags &= ~RTF_REJECT; 780 ln->ln_asked = 0; 781 if (ln->ln_hold) { 782 /* 783 * we assume ifp is not a loopback here, so just set the 2nd 784 * argument as the 1st one. 785 */ 786 nd6_output(ifp, ifp, ln->ln_hold, 787 (struct sockaddr_in6 *)rt_key(rt), rt); 788 ln->ln_hold = 0; 789 } 790 791 freeit: 792 m_freem(m); 793 return; 794 795 bad: 796 icmp6stat.icp6s_badna++; 797 m_freem(m); 798 } 799 800 /* 801 * Neighbor advertisement output handling. 802 * 803 * Based on RFC 2461 804 * 805 * the following items are not implemented yet: 806 * - proxy advertisement delay rule (RFC2461 7.2.8, last paragraph, SHOULD) 807 * - anycast advertisement delay rule (RFC2461 7.2.7, SHOULD) 808 */ 809 void 810 nd6_na_output(struct ifnet *ifp, const struct in6_addr *daddr6, 811 const struct in6_addr *taddr6, u_long flags, 812 int tlladdr, /* 1 if include target link-layer address */ 813 struct sockaddr *sdl0) /* sockaddr_dl (= proxy NA) or NULL */ 814 { 815 struct mbuf *m; 816 struct ip6_hdr *ip6; 817 struct nd_neighbor_advert *nd_na; 818 struct in6_ifaddr *ia = NULL; 819 struct ip6_moptions im6o; 820 int icmp6len; 821 int maxlen; 822 caddr_t mac; 823 struct ifnet *outif = NULL; 824 825 /* estimate the size of message */ 826 maxlen = sizeof(*ip6) + sizeof(*nd_na); 827 maxlen += (sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7; 828 if (max_linkhdr + maxlen >= MCLBYTES) { 829 #ifdef DIAGNOSTIC 830 kprintf("nd6_na_output: max_linkhdr + maxlen >= MCLBYTES " 831 "(%d + %d > %d)\n", max_linkhdr, maxlen, MCLBYTES); 832 #endif 833 return; 834 } 835 836 m = m_getb(max_linkhdr + maxlen, MB_DONTWAIT, MT_DATA, M_PKTHDR); 837 if (m == NULL) 838 return; 839 840 if (IN6_IS_ADDR_MULTICAST(daddr6)) { 841 m->m_flags |= M_MCAST; 842 im6o.im6o_multicast_ifp = ifp; 843 im6o.im6o_multicast_hlim = 255; 844 im6o.im6o_multicast_loop = 0; 845 } 846 847 icmp6len = sizeof(*nd_na); 848 m->m_pkthdr.len = m->m_len = sizeof(struct ip6_hdr) + icmp6len; 849 m->m_data += max_linkhdr; /* or MH_ALIGN() equivalent? */ 850 851 /* fill neighbor advertisement packet */ 852 ip6 = mtod(m, struct ip6_hdr *); 853 ip6->ip6_flow = 0; 854 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 855 ip6->ip6_vfc |= IPV6_VERSION; 856 ip6->ip6_nxt = IPPROTO_ICMPV6; 857 ip6->ip6_hlim = 255; 858 if (IN6_IS_ADDR_UNSPECIFIED(daddr6)) { 859 /* reply to DAD */ 860 ip6->ip6_dst.s6_addr16[0] = IPV6_ADDR_INT16_MLL; 861 ip6->ip6_dst.s6_addr16[1] = htons(ifp->if_index); 862 ip6->ip6_dst.s6_addr32[1] = 0; 863 ip6->ip6_dst.s6_addr32[2] = 0; 864 ip6->ip6_dst.s6_addr32[3] = IPV6_ADDR_INT32_ONE; 865 flags &= ~ND_NA_FLAG_SOLICITED; 866 } else 867 ip6->ip6_dst = *daddr6; 868 869 /* 870 * Select a source whose scope is the same as that of the dest. 871 */ 872 ia = in6_ifawithifp(ifp, &ip6->ip6_dst); 873 if (ia == NULL) { 874 m_freem(m); 875 return; 876 } 877 ip6->ip6_src = ia->ia_addr.sin6_addr; 878 nd_na = (struct nd_neighbor_advert *)(ip6 + 1); 879 nd_na->nd_na_type = ND_NEIGHBOR_ADVERT; 880 nd_na->nd_na_code = 0; 881 nd_na->nd_na_target = *taddr6; 882 if (IN6_IS_SCOPE_LINKLOCAL(&nd_na->nd_na_target)) 883 nd_na->nd_na_target.s6_addr16[1] = 0; 884 885 /* 886 * "tlladdr" indicates NS's condition for adding tlladdr or not. 887 * see nd6_ns_input() for details. 888 * Basically, if NS packet is sent to unicast/anycast addr, 889 * target lladdr option SHOULD NOT be included. 890 */ 891 mac = NULL; 892 if (tlladdr) { 893 /* 894 * sdl0 != NULL indicates proxy NA. If we do proxy, use 895 * lladdr in sdl0. If we are not proxying (sending NA for 896 * my address) use lladdr configured for the interface. 897 */ 898 if (sdl0 == NULL) 899 mac = nd6_ifptomac(ifp); 900 else if (sdl0->sa_family == AF_LINK) { 901 struct sockaddr_dl *sdl; 902 sdl = (struct sockaddr_dl *)sdl0; 903 if (sdl->sdl_alen == ifp->if_addrlen) 904 mac = LLADDR(sdl); 905 } 906 } 907 if (mac != NULL) { 908 int optlen = sizeof(struct nd_opt_hdr) + ifp->if_addrlen; 909 struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)(nd_na + 1); 910 911 /* roundup to 8 bytes alignment! */ 912 optlen = (optlen + 7) & ~7; 913 914 m->m_pkthdr.len += optlen; 915 m->m_len += optlen; 916 icmp6len += optlen; 917 bzero((caddr_t)nd_opt, optlen); 918 nd_opt->nd_opt_type = ND_OPT_TARGET_LINKADDR; 919 nd_opt->nd_opt_len = optlen >> 3; 920 bcopy(mac, (caddr_t)(nd_opt + 1), ifp->if_addrlen); 921 } else 922 flags &= ~ND_NA_FLAG_OVERRIDE; 923 924 ip6->ip6_plen = htons((u_short)icmp6len); 925 nd_na->nd_na_flags_reserved = flags; 926 nd_na->nd_na_cksum = 0; 927 nd_na->nd_na_cksum = 928 in6_cksum(m, IPPROTO_ICMPV6, sizeof(struct ip6_hdr), icmp6len); 929 930 ip6_output(m, NULL, NULL, 0, &im6o, &outif, NULL); 931 if (outif) { 932 icmp6_ifstat_inc(outif, ifs6_out_msg); 933 icmp6_ifstat_inc(outif, ifs6_out_neighboradvert); 934 } 935 icmp6stat.icp6s_outhist[ND_NEIGHBOR_ADVERT]++; 936 } 937 938 caddr_t 939 nd6_ifptomac(struct ifnet *ifp) 940 { 941 switch (ifp->if_type) { 942 case IFT_ARCNET: 943 case IFT_ETHER: 944 case IFT_FDDI: 945 case IFT_IEEE1394: 946 #ifdef IFT_L2VLAN 947 case IFT_L2VLAN: 948 #endif 949 #ifdef IFT_IEEE80211 950 case IFT_IEEE80211: 951 #endif 952 return ((caddr_t)(ifp + 1)); 953 break; 954 default: 955 return NULL; 956 } 957 } 958 959 TAILQ_HEAD(dadq_head, dadq); 960 struct dadq { 961 TAILQ_ENTRY(dadq) dad_list; 962 struct ifaddr *dad_ifa; 963 int dad_count; /* max NS to send */ 964 int dad_ns_tcount; /* # of trials to send NS */ 965 int dad_ns_ocount; /* NS sent so far */ 966 int dad_ns_icount; 967 int dad_na_icount; 968 struct callout dad_timer_ch; 969 }; 970 971 static struct dadq_head dadq; 972 static int dad_init = 0; 973 974 static struct dadq * 975 nd6_dad_find(struct ifaddr *ifa) 976 { 977 struct dadq *dp; 978 979 TAILQ_FOREACH(dp, &dadq, dad_list) { 980 if (dp->dad_ifa == ifa) 981 return dp; 982 } 983 return NULL; 984 } 985 986 static void 987 nd6_dad_starttimer(struct dadq *dp, int ticks) 988 { 989 990 callout_reset(&dp->dad_timer_ch, ticks, 991 (void (*) (void *))nd6_dad_timer, (void *)dp->dad_ifa); 992 } 993 994 static void 995 nd6_dad_stoptimer(struct dadq *dp) 996 { 997 998 callout_stop(&dp->dad_timer_ch); 999 } 1000 1001 /* 1002 * Start Duplicated Address Detection (DAD) for specified interface address. 1003 */ 1004 void 1005 nd6_dad_start(struct ifaddr *ifa, 1006 int *tick) /* minimum delay ticks for IFF_UP event */ 1007 { 1008 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1009 struct dadq *dp; 1010 1011 if (!dad_init) { 1012 TAILQ_INIT(&dadq); 1013 dad_init++; 1014 } 1015 1016 /* 1017 * If we don't need DAD, don't do it. 1018 * There are several cases: 1019 * - DAD is disabled (ip6_dad_count == 0) 1020 * - the interface address is anycast 1021 */ 1022 if (!(ia->ia6_flags & IN6_IFF_TENTATIVE)) { 1023 log(LOG_DEBUG, 1024 "nd6_dad_start: called with non-tentative address " 1025 "%s(%s)\n", 1026 ip6_sprintf(&ia->ia_addr.sin6_addr), 1027 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1028 return; 1029 } 1030 if (ia->ia6_flags & IN6_IFF_ANYCAST) { 1031 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1032 return; 1033 } 1034 if (!ip6_dad_count) { 1035 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1036 return; 1037 } 1038 if (!ifa->ifa_ifp) 1039 panic("nd6_dad_start: ifa->ifa_ifp == NULL"); 1040 if (!(ifa->ifa_ifp->if_flags & IFF_UP)) 1041 return; 1042 if (nd6_dad_find(ifa) != NULL) { 1043 /* DAD already in progress */ 1044 return; 1045 } 1046 1047 dp = kmalloc(sizeof(*dp), M_IP6NDP, M_NOWAIT); 1048 if (dp == NULL) { 1049 log(LOG_ERR, "nd6_dad_start: memory allocation failed for " 1050 "%s(%s)\n", 1051 ip6_sprintf(&ia->ia_addr.sin6_addr), 1052 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1053 return; 1054 } 1055 bzero(dp, sizeof(*dp)); 1056 callout_init(&dp->dad_timer_ch); 1057 TAILQ_INSERT_TAIL(&dadq, (struct dadq *)dp, dad_list); 1058 1059 nd6log((LOG_DEBUG, "%s: starting DAD for %s\n", if_name(ifa->ifa_ifp), 1060 ip6_sprintf(&ia->ia_addr.sin6_addr))); 1061 1062 /* 1063 * Send NS packet for DAD, ip6_dad_count times. 1064 * Note that we must delay the first transmission, if this is the 1065 * first packet to be sent from the interface after interface 1066 * (re)initialization. 1067 */ 1068 dp->dad_ifa = ifa; 1069 IFAREF(ifa); /* just for safety */ 1070 dp->dad_count = ip6_dad_count; 1071 dp->dad_ns_icount = dp->dad_na_icount = 0; 1072 dp->dad_ns_ocount = dp->dad_ns_tcount = 0; 1073 if (tick == NULL) { 1074 nd6_dad_ns_output(dp, ifa); 1075 nd6_dad_starttimer(dp, 1076 ND_IFINFO(ifa->ifa_ifp)->retrans * hz / 1000); 1077 } else { 1078 int ntick; 1079 1080 if (*tick == 0) 1081 ntick = krandom() % (MAX_RTR_SOLICITATION_DELAY * hz); 1082 else 1083 ntick = *tick + krandom() % (hz / 2); 1084 *tick = ntick; 1085 nd6_dad_starttimer(dp, ntick); 1086 } 1087 } 1088 1089 /* 1090 * terminate DAD unconditionally. used for address removals. 1091 */ 1092 void 1093 nd6_dad_stop(struct ifaddr *ifa) 1094 { 1095 struct dadq *dp; 1096 1097 if (!dad_init) 1098 return; 1099 dp = nd6_dad_find(ifa); 1100 if (!dp) { 1101 /* DAD wasn't started yet */ 1102 return; 1103 } 1104 1105 nd6_dad_stoptimer(dp); 1106 1107 TAILQ_REMOVE(&dadq, (struct dadq *)dp, dad_list); 1108 kfree(dp, M_IP6NDP); 1109 dp = NULL; 1110 IFAFREE(ifa); 1111 } 1112 1113 static void 1114 nd6_dad_timer(struct ifaddr *ifa) 1115 { 1116 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1117 struct dadq *dp; 1118 1119 crit_enter(); /* XXX */ 1120 1121 /* Sanity check */ 1122 if (ia == NULL) { 1123 log(LOG_ERR, "nd6_dad_timer: called with null parameter\n"); 1124 goto done; 1125 } 1126 dp = nd6_dad_find(ifa); 1127 if (dp == NULL) { 1128 log(LOG_ERR, "nd6_dad_timer: DAD structure not found\n"); 1129 goto done; 1130 } 1131 if (ia->ia6_flags & IN6_IFF_DUPLICATED) { 1132 log(LOG_ERR, "nd6_dad_timer: called with duplicated address " 1133 "%s(%s)\n", 1134 ip6_sprintf(&ia->ia_addr.sin6_addr), 1135 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1136 goto done; 1137 } 1138 if (!(ia->ia6_flags & IN6_IFF_TENTATIVE)) { 1139 log(LOG_ERR, "nd6_dad_timer: 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 goto done; 1144 } 1145 1146 /* timeouted with IFF_{RUNNING,UP} check */ 1147 if (dp->dad_ns_tcount > dad_maxtry) { 1148 nd6log((LOG_INFO, "%s: could not run DAD, driver problem?\n", 1149 if_name(ifa->ifa_ifp))); 1150 1151 TAILQ_REMOVE(&dadq, (struct dadq *)dp, dad_list); 1152 kfree(dp, M_IP6NDP); 1153 dp = NULL; 1154 IFAFREE(ifa); 1155 goto done; 1156 } 1157 1158 /* Need more checks? */ 1159 if (dp->dad_ns_ocount < dp->dad_count) { 1160 /* 1161 * We have more NS to go. Send NS packet for DAD. 1162 */ 1163 nd6_dad_ns_output(dp, ifa); 1164 nd6_dad_starttimer(dp, 1165 ND_IFINFO(ifa->ifa_ifp)->retrans * hz / 1000); 1166 } else { 1167 /* 1168 * We have transmitted sufficient number of DAD packets. 1169 * See what we've got. 1170 */ 1171 int duplicate; 1172 1173 duplicate = 0; 1174 1175 if (dp->dad_na_icount) { 1176 /* 1177 * the check is in nd6_dad_na_input(), 1178 * but just in case 1179 */ 1180 duplicate++; 1181 } 1182 1183 if (dp->dad_ns_icount) { 1184 #if 0 /* heuristics */ 1185 /* 1186 * if 1187 * - we have sent many(?) DAD NS, and 1188 * - the number of NS we sent equals to the 1189 * number of NS we've got, and 1190 * - we've got no NA 1191 * we may have a faulty network card/driver which 1192 * loops back multicasts to myself. 1193 */ 1194 if (3 < dp->dad_count 1195 && dp->dad_ns_icount == dp->dad_count 1196 && dp->dad_na_icount == 0) { 1197 log(LOG_INFO, "DAD questionable for %s(%s): " 1198 "network card loops back multicast?\n", 1199 ip6_sprintf(&ia->ia_addr.sin6_addr), 1200 if_name(ifa->ifa_ifp)); 1201 /* XXX consider it a duplicate or not? */ 1202 /* duplicate++; */ 1203 } else { 1204 /* We've seen NS, means DAD has failed. */ 1205 duplicate++; 1206 } 1207 #else 1208 /* We've seen NS, means DAD has failed. */ 1209 duplicate++; 1210 #endif 1211 } 1212 1213 if (duplicate) { 1214 /* (*dp) will be freed in nd6_dad_duplicated() */ 1215 dp = NULL; 1216 nd6_dad_duplicated(ifa); 1217 } else { 1218 /* 1219 * We are done with DAD. No NA came, no NS came. 1220 * duplicated address found. 1221 */ 1222 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1223 1224 nd6log((LOG_DEBUG, 1225 "%s: DAD complete for %s - no duplicates found\n", 1226 if_name(ifa->ifa_ifp), 1227 ip6_sprintf(&ia->ia_addr.sin6_addr))); 1228 1229 TAILQ_REMOVE(&dadq, (struct dadq *)dp, dad_list); 1230 kfree(dp, M_IP6NDP); 1231 dp = NULL; 1232 IFAFREE(ifa); 1233 } 1234 } 1235 1236 done: 1237 crit_exit(); 1238 } 1239 1240 void 1241 nd6_dad_duplicated(struct ifaddr *ifa) 1242 { 1243 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1244 struct dadq *dp; 1245 1246 dp = nd6_dad_find(ifa); 1247 if (dp == NULL) { 1248 log(LOG_ERR, "nd6_dad_duplicated: DAD structure not found\n"); 1249 return; 1250 } 1251 1252 log(LOG_ERR, "%s: DAD detected duplicate IPv6 address %s: " 1253 "NS in/out=%d/%d, NA in=%d\n", 1254 if_name(ifa->ifa_ifp), ip6_sprintf(&ia->ia_addr.sin6_addr), 1255 dp->dad_ns_icount, dp->dad_ns_ocount, dp->dad_na_icount); 1256 1257 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1258 ia->ia6_flags |= IN6_IFF_DUPLICATED; 1259 1260 /* We are done with DAD, with duplicated address found. (failure) */ 1261 nd6_dad_stoptimer(dp); 1262 1263 log(LOG_ERR, "%s: DAD complete for %s - duplicate found\n", 1264 if_name(ifa->ifa_ifp), ip6_sprintf(&ia->ia_addr.sin6_addr)); 1265 log(LOG_ERR, "%s: manual intervention required\n", 1266 if_name(ifa->ifa_ifp)); 1267 1268 TAILQ_REMOVE(&dadq, (struct dadq *)dp, dad_list); 1269 kfree(dp, M_IP6NDP); 1270 dp = NULL; 1271 IFAFREE(ifa); 1272 } 1273 1274 static void 1275 nd6_dad_ns_output(struct dadq *dp, struct ifaddr *ifa) 1276 { 1277 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1278 struct ifnet *ifp = ifa->ifa_ifp; 1279 1280 dp->dad_ns_tcount++; 1281 if (!(ifp->if_flags & IFF_UP)) { 1282 #if 0 1283 kprintf("%s: interface down?\n", if_name(ifp)); 1284 #endif 1285 return; 1286 } 1287 if (!(ifp->if_flags & IFF_RUNNING)) { 1288 #if 0 1289 kprintf("%s: interface not running?\n", if_name(ifp)); 1290 #endif 1291 return; 1292 } 1293 1294 dp->dad_ns_ocount++; 1295 nd6_ns_output(ifp, NULL, &ia->ia_addr.sin6_addr, NULL, 1); 1296 } 1297 1298 static void 1299 nd6_dad_ns_input(struct ifaddr *ifa) 1300 { 1301 struct in6_ifaddr *ia; 1302 struct ifnet *ifp; 1303 const struct in6_addr *taddr6; 1304 struct dadq *dp; 1305 int duplicate; 1306 1307 if (!ifa) 1308 panic("ifa == NULL in nd6_dad_ns_input"); 1309 1310 ia = (struct in6_ifaddr *)ifa; 1311 ifp = ifa->ifa_ifp; 1312 taddr6 = &ia->ia_addr.sin6_addr; 1313 duplicate = 0; 1314 dp = nd6_dad_find(ifa); 1315 1316 /* Quickhack - completely ignore DAD NS packets */ 1317 if (dad_ignore_ns) { 1318 nd6log((LOG_INFO, 1319 "nd6_dad_ns_input: ignoring DAD NS packet for " 1320 "address %s(%s)\n", ip6_sprintf(taddr6), 1321 if_name(ifa->ifa_ifp))); 1322 return; 1323 } 1324 1325 /* 1326 * if I'm yet to start DAD, someone else started using this address 1327 * first. I have a duplicate and you win. 1328 */ 1329 if (!dp || dp->dad_ns_ocount == 0) 1330 duplicate++; 1331 1332 /* XXX more checks for loopback situation - see nd6_dad_timer too */ 1333 1334 if (duplicate) { 1335 dp = NULL; /* will be freed in nd6_dad_duplicated() */ 1336 nd6_dad_duplicated(ifa); 1337 } else { 1338 /* 1339 * not sure if I got a duplicate. 1340 * increment ns count and see what happens. 1341 */ 1342 if (dp) 1343 dp->dad_ns_icount++; 1344 } 1345 } 1346 1347 static void 1348 nd6_dad_na_input(struct ifaddr *ifa) 1349 { 1350 struct dadq *dp; 1351 1352 if (!ifa) 1353 panic("ifa == NULL in nd6_dad_na_input"); 1354 1355 dp = nd6_dad_find(ifa); 1356 if (dp) 1357 dp->dad_na_icount++; 1358 1359 /* remove the address. */ 1360 nd6_dad_duplicated(ifa); 1361 } 1362