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 1.23 2008/03/07 11:34:21 sephe 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 #include "opt_carp.h" 38 39 #include <sys/param.h> 40 #include <sys/systm.h> 41 #include <sys/malloc.h> 42 #include <sys/mbuf.h> 43 #include <sys/socket.h> 44 #include <sys/sockio.h> 45 #include <sys/time.h> 46 #include <sys/kernel.h> 47 #include <sys/errno.h> 48 #include <sys/syslog.h> 49 #include <sys/queue.h> 50 #include <sys/callout.h> 51 #include <sys/thread2.h> 52 53 #include <net/if.h> 54 #include <net/if_types.h> 55 #include <net/if_dl.h> 56 #include <net/route.h> 57 58 #include <netinet/in.h> 59 #include <netinet/in_var.h> 60 #include <netinet6/in6_var.h> 61 #include <netinet/ip6.h> 62 #include <netinet6/ip6_var.h> 63 #include <netinet6/nd6.h> 64 #include <netinet/icmp6.h> 65 66 #ifdef IPSEC 67 #include <netinet6/ipsec.h> 68 #ifdef INET6 69 #include <netinet6/ipsec6.h> 70 #endif 71 #endif 72 73 #include <net/net_osdep.h> 74 75 #ifdef CARP 76 #include <netinet/ip_carp.h> 77 #endif 78 79 80 #define SDL(s) ((struct sockaddr_dl *)s) 81 82 struct dadq; 83 static struct dadq *nd6_dad_find (struct ifaddr *); 84 static void nd6_dad_starttimer (struct dadq *, int); 85 static void nd6_dad_stoptimer (struct dadq *); 86 static void nd6_dad_timer (struct ifaddr *); 87 static void nd6_dad_ns_output (struct dadq *, struct ifaddr *); 88 static void nd6_dad_ns_input (struct ifaddr *); 89 static void nd6_dad_na_input (struct ifaddr *); 90 91 static int dad_ignore_ns = 0; /* ignore NS in DAD - specwise incorrect*/ 92 static int dad_maxtry = 15; /* max # of *tries* to transmit DAD packet */ 93 94 /* 95 * Input an Neighbor Solicitation Message. 96 * 97 * Based on RFC 2461 98 * Based on RFC 2462 (duplicated address detection) 99 */ 100 void 101 nd6_ns_input(struct mbuf *m, int off, int icmp6len) 102 { 103 struct ifnet *ifp = m->m_pkthdr.rcvif; 104 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 105 struct nd_neighbor_solicit *nd_ns; 106 struct in6_addr saddr6 = ip6->ip6_src; 107 struct in6_addr daddr6 = ip6->ip6_dst; 108 struct in6_addr taddr6; 109 struct in6_addr myaddr6; 110 char *lladdr = NULL; 111 struct ifaddr *ifa = NULL; 112 int lladdrlen = 0; 113 int anycast = 0, proxy = 0, tentative = 0; 114 int tlladdr; 115 union nd_opts ndopts; 116 struct sockaddr_dl *proxydl = NULL; 117 118 #ifndef PULLDOWN_TEST 119 IP6_EXTHDR_CHECK(m, off, icmp6len,); 120 nd_ns = (struct nd_neighbor_solicit *)((caddr_t)ip6 + off); 121 #else 122 IP6_EXTHDR_GET(nd_ns, struct nd_neighbor_solicit *, m, off, icmp6len); 123 if (nd_ns == NULL) { 124 icmp6stat.icp6s_tooshort++; 125 return; 126 } 127 #endif 128 ip6 = mtod(m, struct ip6_hdr *); /* adjust pointer for safety */ 129 taddr6 = nd_ns->nd_ns_target; 130 131 if (ip6->ip6_hlim != 255) { 132 nd6log((LOG_ERR, 133 "nd6_ns_input: invalid hlim (%d) from %s to %s on %s\n", 134 ip6->ip6_hlim, ip6_sprintf(&ip6->ip6_src), 135 ip6_sprintf(&ip6->ip6_dst), if_name(ifp))); 136 goto bad; 137 } 138 139 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) { 140 /* dst has to be solicited node multicast address. */ 141 if (daddr6.s6_addr16[0] == IPV6_ADDR_INT16_MLL 142 /* don't check ifindex portion */ 143 && daddr6.s6_addr32[1] == 0 144 && daddr6.s6_addr32[2] == IPV6_ADDR_INT32_ONE 145 && daddr6.s6_addr8[12] == 0xff) { 146 ; /* good */ 147 } else { 148 nd6log((LOG_INFO, "nd6_ns_input: bad DAD packet " 149 "(wrong ip6 dst)\n")); 150 goto bad; 151 } 152 } 153 154 if (IN6_IS_ADDR_MULTICAST(&taddr6)) { 155 nd6log((LOG_INFO, "nd6_ns_input: bad NS target (multicast)\n")); 156 goto bad; 157 } 158 159 if (IN6_IS_SCOPE_LINKLOCAL(&taddr6)) 160 taddr6.s6_addr16[1] = htons(ifp->if_index); 161 162 icmp6len -= sizeof(*nd_ns); 163 nd6_option_init(nd_ns + 1, icmp6len, &ndopts); 164 if (nd6_options(&ndopts) < 0) { 165 nd6log((LOG_INFO, 166 "nd6_ns_input: invalid ND option, ignored\n")); 167 /* nd6_options have incremented stats */ 168 goto freeit; 169 } 170 171 if (ndopts.nd_opts_src_lladdr) { 172 lladdr = (char *)(ndopts.nd_opts_src_lladdr + 1); 173 lladdrlen = ndopts.nd_opts_src_lladdr->nd_opt_len << 3; 174 } 175 176 if (IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_src) && lladdr) { 177 nd6log((LOG_INFO, "nd6_ns_input: bad DAD packet " 178 "(link-layer address option)\n")); 179 goto bad; 180 } 181 182 /* 183 * Attaching target link-layer address to the NA? 184 * (RFC 2461 7.2.4) 185 * 186 * NS IP dst is unicast/anycast MUST NOT add 187 * NS IP dst is solicited-node multicast MUST add 188 * 189 * In implementation, we add target link-layer address by default. 190 * We do not add one in MUST NOT cases. 191 */ 192 #if 0 /* too much! */ 193 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &daddr6); 194 if (ifa && (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_ANYCAST)) 195 tlladdr = 0; 196 else 197 #endif 198 if (!IN6_IS_ADDR_MULTICAST(&daddr6)) 199 tlladdr = 0; 200 else 201 tlladdr = 1; 202 203 /* 204 * Target address (taddr6) must be either: 205 * (1) Valid unicast/anycast address for my receiving interface, 206 * (2) Unicast address for which I'm offering proxy service, or 207 * (3) "tentative" address on which DAD is being performed. 208 */ 209 /* (1) and (3) check. */ 210 #ifdef CARP 211 if (ifp->if_carp) 212 ifa = carp_iamatch6(ifp->if_carp, &taddr6); 213 if (!ifa) 214 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &taddr6); 215 #else 216 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &taddr6); 217 #endif 218 219 /* (2) check. */ 220 if (!ifa) { 221 struct rtentry *rt; 222 struct sockaddr_in6 tsin6; 223 224 bzero(&tsin6, sizeof tsin6); 225 tsin6.sin6_len = sizeof(struct sockaddr_in6); 226 tsin6.sin6_family = AF_INET6; 227 tsin6.sin6_addr = taddr6; 228 229 rt = rtpurelookup((struct sockaddr *)&tsin6); 230 if (rt != NULL && (rt->rt_flags & RTF_ANNOUNCE) && 231 rt->rt_gateway->sa_family == AF_LINK) { 232 /* 233 * proxy NDP for single entry 234 */ 235 ifa = (struct ifaddr *)in6ifa_ifpforlinklocal(ifp, 236 IN6_IFF_NOTREADY|IN6_IFF_ANYCAST); 237 if (ifa) { 238 proxy = 1; 239 proxydl = SDL(rt->rt_gateway); 240 } 241 } 242 if (rt != NULL) 243 --rt->rt_refcnt; 244 } 245 if (ifa == NULL) { 246 /* 247 * We've got an NS packet, and we don't have that adddress 248 * assigned for us. We MUST silently ignore it. 249 * See RFC2461 7.2.3. 250 */ 251 goto freeit; 252 } 253 myaddr6 = *IFA_IN6(ifa); 254 anycast = ((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_ANYCAST; 255 tentative = ((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_TENTATIVE; 256 if (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_DUPLICATED) 257 goto freeit; 258 259 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) { 260 nd6log((LOG_INFO, 261 "nd6_ns_input: lladdrlen mismatch for %s " 262 "(if %d, NS packet %d)\n", 263 ip6_sprintf(&taddr6), ifp->if_addrlen, lladdrlen - 2)); 264 goto bad; 265 } 266 267 if (IN6_ARE_ADDR_EQUAL(&myaddr6, &saddr6)) { 268 nd6log((LOG_INFO, 269 "nd6_ns_input: duplicate IP6 address %s\n", 270 ip6_sprintf(&saddr6))); 271 goto freeit; 272 } 273 274 /* 275 * We have neighbor solicitation packet, with target address equals to 276 * one of my tentative address. 277 * 278 * src addr how to process? 279 * --- --- 280 * multicast of course, invalid (rejected in ip6_input) 281 * unicast somebody is doing address resolution -> ignore 282 * unspec dup address detection 283 * 284 * The processing is defined in RFC 2462. 285 */ 286 if (tentative) { 287 /* 288 * If source address is unspecified address, it is for 289 * duplicated address detection. 290 * 291 * If not, the packet is for addess resolution; 292 * silently ignore it. 293 */ 294 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) 295 nd6_dad_ns_input(ifa); 296 297 goto freeit; 298 } 299 300 /* 301 * If the source address is unspecified address, entries must not 302 * be created or updated. 303 * It looks that sender is performing DAD. Output NA toward 304 * all-node multicast address, to tell the sender that I'm using 305 * the address. 306 * S bit ("solicited") must be zero. 307 */ 308 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) { 309 saddr6 = kin6addr_linklocal_allnodes; 310 saddr6.s6_addr16[1] = htons(ifp->if_index); 311 nd6_na_output(ifp, &saddr6, &taddr6, 312 ((anycast || proxy || !tlladdr) 313 ? 0 : ND_NA_FLAG_OVERRIDE) 314 | (ip6_forwarding ? ND_NA_FLAG_ROUTER : 0), 315 tlladdr, (struct sockaddr *)proxydl); 316 goto freeit; 317 } 318 319 nd6_cache_lladdr(ifp, &saddr6, lladdr, lladdrlen, ND_NEIGHBOR_SOLICIT, 0); 320 321 nd6_na_output(ifp, &saddr6, &taddr6, 322 ((anycast || proxy || !tlladdr) ? 0 : ND_NA_FLAG_OVERRIDE) 323 | (ip6_forwarding ? ND_NA_FLAG_ROUTER : 0) 324 | ND_NA_FLAG_SOLICITED, 325 tlladdr, (struct sockaddr *)proxydl); 326 freeit: 327 m_freem(m); 328 return; 329 330 bad: 331 nd6log((LOG_ERR, "nd6_ns_input: src=%s\n", ip6_sprintf(&saddr6))); 332 nd6log((LOG_ERR, "nd6_ns_input: dst=%s\n", ip6_sprintf(&daddr6))); 333 nd6log((LOG_ERR, "nd6_ns_input: tgt=%s\n", ip6_sprintf(&taddr6))); 334 icmp6stat.icp6s_badns++; 335 m_freem(m); 336 } 337 338 /* 339 * Output an Neighbor Solicitation Message. Caller specifies: 340 * - ICMP6 header source IP6 address 341 * - ND6 header target IP6 address 342 * - ND6 header source datalink address 343 * 344 * Based on RFC 2461 345 * Based on RFC 2462 (duplicated address detection) 346 */ 347 void 348 nd6_ns_output(struct ifnet *ifp, const struct in6_addr *daddr6, 349 const struct in6_addr *taddr6, 350 struct llinfo_nd6 *ln, /* for source address determination */ 351 int dad) /* duplicated address detection */ 352 { 353 struct mbuf *m; 354 struct ip6_hdr *ip6; 355 struct nd_neighbor_solicit *nd_ns; 356 struct in6_ifaddr *ia = NULL; 357 struct ip6_moptions im6o; 358 int icmp6len; 359 int maxlen; 360 caddr_t mac; 361 struct ifnet *outif = NULL; 362 363 if (IN6_IS_ADDR_MULTICAST(taddr6)) 364 return; 365 366 /* estimate the size of message */ 367 maxlen = sizeof(*ip6) + sizeof(*nd_ns); 368 maxlen += (sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7; 369 if (max_linkhdr + maxlen >= MCLBYTES) { 370 #ifdef DIAGNOSTIC 371 kprintf("nd6_ns_output: max_linkhdr + maxlen >= MCLBYTES " 372 "(%d + %d > %d)\n", max_linkhdr, maxlen, MCLBYTES); 373 #endif 374 return; 375 } 376 377 m = m_getb(max_linkhdr + maxlen, MB_DONTWAIT, MT_DATA, M_PKTHDR); 378 if (m == NULL) 379 return; 380 381 if (daddr6 == NULL || IN6_IS_ADDR_MULTICAST(daddr6)) { 382 m->m_flags |= M_MCAST; 383 im6o.im6o_multicast_ifp = ifp; 384 im6o.im6o_multicast_hlim = 255; 385 im6o.im6o_multicast_loop = 0; 386 } 387 388 icmp6len = sizeof(*nd_ns); 389 m->m_pkthdr.len = m->m_len = sizeof(*ip6) + icmp6len; 390 m->m_data += max_linkhdr; /* or MH_ALIGN() equivalent? */ 391 392 /* fill neighbor solicitation packet */ 393 ip6 = mtod(m, struct ip6_hdr *); 394 ip6->ip6_flow = 0; 395 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 396 ip6->ip6_vfc |= IPV6_VERSION; 397 /* ip6->ip6_plen will be set later */ 398 ip6->ip6_nxt = IPPROTO_ICMPV6; 399 ip6->ip6_hlim = 255; 400 if (daddr6) 401 ip6->ip6_dst = *daddr6; 402 else { 403 ip6->ip6_dst.s6_addr16[0] = IPV6_ADDR_INT16_MLL; 404 ip6->ip6_dst.s6_addr16[1] = htons(ifp->if_index); 405 ip6->ip6_dst.s6_addr32[1] = 0; 406 ip6->ip6_dst.s6_addr32[2] = IPV6_ADDR_INT32_ONE; 407 ip6->ip6_dst.s6_addr32[3] = taddr6->s6_addr32[3]; 408 ip6->ip6_dst.s6_addr8[12] = 0xff; 409 } 410 if (!dad) { 411 #if 0 /* KAME way, exact address scope match */ 412 /* 413 * Select a source whose scope is the same as that of the dest. 414 * Typically, the dest is link-local solicitation multicast 415 * (i.e. neighbor discovery) or link-local/global unicast 416 * (i.e. neighbor un-reachability detection). 417 */ 418 ia = in6_ifawithifp(ifp, &ip6->ip6_dst); 419 if (ia == NULL) { 420 m_freem(m); 421 return; 422 } 423 ip6->ip6_src = ia->ia_addr.sin6_addr; 424 #else /* spec-wise correct */ 425 /* 426 * RFC2461 7.2.2: 427 * "If the source address of the packet prompting the 428 * solicitation is the same as one of the addresses assigned 429 * to the outgoing interface, that address SHOULD be placed 430 * in the IP Source Address of the outgoing solicitation. 431 * Otherwise, any one of the addresses assigned to the 432 * interface should be used." 433 * 434 * We use the source address for the prompting packet 435 * (saddr6), if: 436 * - saddr6 is given from the caller (by giving "ln"), and 437 * - saddr6 belongs to the outgoing interface. 438 * Otherwise, we perform a scope-wise match. 439 */ 440 struct ip6_hdr *hip6; /* hold ip6 */ 441 struct in6_addr *saddr6; 442 443 if (ln && ln->ln_hold) { 444 hip6 = mtod(ln->ln_hold, struct ip6_hdr *); 445 /* XXX pullup? */ 446 if (sizeof(*hip6) < ln->ln_hold->m_len) 447 saddr6 = &hip6->ip6_src; 448 else 449 saddr6 = NULL; 450 } else 451 saddr6 = NULL; 452 if (saddr6 && in6ifa_ifpwithaddr(ifp, saddr6)) 453 bcopy(saddr6, &ip6->ip6_src, sizeof(*saddr6)); 454 else { 455 ia = in6_ifawithifp(ifp, &ip6->ip6_dst); 456 if (ia == NULL) { 457 m_freem(m); 458 return; 459 } 460 ip6->ip6_src = ia->ia_addr.sin6_addr; 461 } 462 #endif 463 } else { 464 /* 465 * Source address for DAD packet must always be IPv6 466 * unspecified address. (0::0) 467 */ 468 bzero(&ip6->ip6_src, sizeof(ip6->ip6_src)); 469 } 470 nd_ns = (struct nd_neighbor_solicit *)(ip6 + 1); 471 nd_ns->nd_ns_type = ND_NEIGHBOR_SOLICIT; 472 nd_ns->nd_ns_code = 0; 473 nd_ns->nd_ns_reserved = 0; 474 nd_ns->nd_ns_target = *taddr6; 475 476 if (IN6_IS_SCOPE_LINKLOCAL(&nd_ns->nd_ns_target)) 477 nd_ns->nd_ns_target.s6_addr16[1] = 0; 478 479 /* 480 * Add source link-layer address option. 481 * 482 * spec implementation 483 * --- --- 484 * DAD packet MUST NOT do not add the option 485 * there's no link layer address: 486 * impossible do not add the option 487 * there's link layer address: 488 * Multicast NS MUST add one add the option 489 * Unicast NS SHOULD add one add the option 490 */ 491 if (!dad && (mac = nd6_ifptomac(ifp))) { 492 int optlen = sizeof(struct nd_opt_hdr) + ifp->if_addrlen; 493 struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)(nd_ns + 1); 494 /* 8 byte alignments... */ 495 optlen = (optlen + 7) & ~7; 496 497 m->m_pkthdr.len += optlen; 498 m->m_len += optlen; 499 icmp6len += optlen; 500 bzero((caddr_t)nd_opt, optlen); 501 nd_opt->nd_opt_type = ND_OPT_SOURCE_LINKADDR; 502 nd_opt->nd_opt_len = optlen >> 3; 503 bcopy(mac, (caddr_t)(nd_opt + 1), ifp->if_addrlen); 504 } 505 506 ip6->ip6_plen = htons((u_short)icmp6len); 507 nd_ns->nd_ns_cksum = 0; 508 nd_ns->nd_ns_cksum 509 = in6_cksum(m, IPPROTO_ICMPV6, sizeof(*ip6), icmp6len); 510 511 ip6_output(m, NULL, NULL, dad ? IPV6_DADOUTPUT : 0, &im6o, &outif, NULL); 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(struct mbuf *m, int off, int icmp6len) 531 { 532 struct ifnet *ifp = m->m_pkthdr.rcvif; 533 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 534 struct nd_neighbor_advert *nd_na; 535 #if 0 536 struct in6_addr saddr6 = ip6->ip6_src; 537 #endif 538 struct in6_addr daddr6 = ip6->ip6_dst; 539 struct in6_addr taddr6; 540 int flags; 541 int is_router; 542 int is_solicited; 543 int is_override; 544 char *lladdr = NULL; 545 int lladdrlen = 0; 546 struct ifaddr *ifa; 547 struct llinfo_nd6 *ln; 548 struct rtentry *rt; 549 struct sockaddr_dl *sdl; 550 union nd_opts ndopts; 551 552 if (ip6->ip6_hlim != 255) { 553 nd6log((LOG_ERR, 554 "nd6_na_input: invalid hlim (%d) from %s to %s on %s\n", 555 ip6->ip6_hlim, ip6_sprintf(&ip6->ip6_src), 556 ip6_sprintf(&ip6->ip6_dst), if_name(ifp))); 557 goto bad; 558 } 559 560 #ifndef PULLDOWN_TEST 561 IP6_EXTHDR_CHECK(m, off, icmp6len,); 562 nd_na = (struct nd_neighbor_advert *)((caddr_t)ip6 + off); 563 #else 564 IP6_EXTHDR_GET(nd_na, struct nd_neighbor_advert *, m, off, icmp6len); 565 if (nd_na == NULL) { 566 icmp6stat.icp6s_tooshort++; 567 return; 568 } 569 #endif 570 taddr6 = nd_na->nd_na_target; 571 flags = nd_na->nd_na_flags_reserved; 572 is_router = ((flags & ND_NA_FLAG_ROUTER) != 0); 573 is_solicited = ((flags & ND_NA_FLAG_SOLICITED) != 0); 574 is_override = ((flags & ND_NA_FLAG_OVERRIDE) != 0); 575 576 if (IN6_IS_SCOPE_LINKLOCAL(&taddr6)) 577 taddr6.s6_addr16[1] = htons(ifp->if_index); 578 579 if (IN6_IS_ADDR_MULTICAST(&taddr6)) { 580 nd6log((LOG_ERR, 581 "nd6_na_input: invalid target address %s\n", 582 ip6_sprintf(&taddr6))); 583 goto bad; 584 } 585 if (IN6_IS_ADDR_MULTICAST(&daddr6)) 586 if (is_solicited) { 587 nd6log((LOG_ERR, 588 "nd6_na_input: a solicited adv is multicasted\n")); 589 goto bad; 590 } 591 592 icmp6len -= sizeof(*nd_na); 593 nd6_option_init(nd_na + 1, icmp6len, &ndopts); 594 if (nd6_options(&ndopts) < 0) { 595 nd6log((LOG_INFO, 596 "nd6_na_input: invalid ND option, ignored\n")); 597 /* nd6_options have incremented stats */ 598 goto freeit; 599 } 600 601 if (ndopts.nd_opts_tgt_lladdr) { 602 lladdr = (char *)(ndopts.nd_opts_tgt_lladdr + 1); 603 lladdrlen = ndopts.nd_opts_tgt_lladdr->nd_opt_len << 3; 604 } 605 606 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &taddr6); 607 608 /* 609 * Target address matches one of my interface address. 610 * 611 * If my address is tentative, this means that there's somebody 612 * already using the same address as mine. This indicates DAD failure. 613 * This is defined in RFC 2462. 614 * 615 * Otherwise, process as defined in RFC 2461. 616 */ 617 if (ifa 618 && (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_TENTATIVE)) { 619 nd6_dad_na_input(ifa); 620 goto freeit; 621 } 622 623 /* Just for safety, maybe unnecessary. */ 624 if (ifa) { 625 log(LOG_ERR, 626 "nd6_na_input: duplicate IP6 address %s\n", 627 ip6_sprintf(&taddr6)); 628 goto freeit; 629 } 630 631 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) { 632 nd6log((LOG_INFO, 633 "nd6_na_input: lladdrlen mismatch for %s " 634 "(if %d, NA packet %d)\n", 635 ip6_sprintf(&taddr6), ifp->if_addrlen, lladdrlen - 2)); 636 goto bad; 637 } 638 639 /* 640 * If no neighbor cache entry is found, NA SHOULD silently be discarded. 641 */ 642 rt = nd6_lookup(&taddr6, 0, ifp); 643 if ((rt == NULL) || 644 ((ln = (struct llinfo_nd6 *)rt->rt_llinfo) == NULL) || 645 ((sdl = SDL(rt->rt_gateway)) == NULL)) 646 goto freeit; 647 648 if (ln->ln_state == ND6_LLINFO_INCOMPLETE) { 649 /* 650 * If the link-layer has address, and no lladdr option came, 651 * discard the packet. 652 */ 653 if (ifp->if_addrlen && !lladdr) 654 goto freeit; 655 656 /* 657 * Record link-layer address, and update the state. 658 */ 659 sdl->sdl_alen = ifp->if_addrlen; 660 bcopy(lladdr, LLADDR(sdl), ifp->if_addrlen); 661 if (is_solicited) { 662 ln->ln_state = ND6_LLINFO_REACHABLE; 663 ln->ln_byhint = 0; 664 if (ln->ln_expire) 665 ln->ln_expire = time_second + 666 ND_IFINFO(rt->rt_ifp)->reachable; 667 } else { 668 ln->ln_state = ND6_LLINFO_STALE; 669 ln->ln_expire = time_second + nd6_gctimer; 670 } 671 if ((ln->ln_router = is_router) != 0) { 672 /* 673 * This means a router's state has changed from 674 * non-reachable to probably reachable, and might 675 * affect the status of associated prefixes.. 676 */ 677 pfxlist_onlink_check(); 678 } 679 } else { 680 int llchange; 681 682 /* 683 * Check if the link-layer address has changed or not. 684 */ 685 if (!lladdr) 686 llchange = 0; 687 else { 688 if (sdl->sdl_alen) { 689 if (bcmp(lladdr, LLADDR(sdl), ifp->if_addrlen)) 690 llchange = 1; 691 else 692 llchange = 0; 693 } else 694 llchange = 1; 695 } 696 697 /* 698 * This is VERY complex. Look at it with care. 699 * 700 * override solicit lladdr llchange action 701 * (L: record lladdr) 702 * 703 * 0 0 n -- (2c) 704 * 0 0 y n (2b) L 705 * 0 0 y y (1) REACHABLE->STALE 706 * 0 1 n -- (2c) *->REACHABLE 707 * 0 1 y n (2b) L *->REACHABLE 708 * 0 1 y y (1) REACHABLE->STALE 709 * 1 0 n -- (2a) 710 * 1 0 y n (2a) L 711 * 1 0 y y (2a) L *->STALE 712 * 1 1 n -- (2a) *->REACHABLE 713 * 1 1 y n (2a) L *->REACHABLE 714 * 1 1 y y (2a) L *->REACHABLE 715 */ 716 if (!is_override && (lladdr && llchange)) { /* (1) */ 717 /* 718 * If state is REACHABLE, make it STALE. 719 * no other updates should be done. 720 */ 721 if (ln->ln_state == ND6_LLINFO_REACHABLE) { 722 ln->ln_state = ND6_LLINFO_STALE; 723 ln->ln_expire = time_second + nd6_gctimer; 724 } 725 goto freeit; 726 } else if (is_override /* (2a) */ 727 || (!is_override && (lladdr && !llchange)) /* (2b) */ 728 || !lladdr) { /* (2c) */ 729 /* 730 * Update link-local address, if any. 731 */ 732 if (lladdr) { 733 sdl->sdl_alen = ifp->if_addrlen; 734 bcopy(lladdr, LLADDR(sdl), ifp->if_addrlen); 735 } 736 737 /* 738 * If solicited, make the state REACHABLE. 739 * If not solicited and the link-layer address was 740 * changed, make it STALE. 741 */ 742 if (is_solicited) { 743 ln->ln_state = ND6_LLINFO_REACHABLE; 744 ln->ln_byhint = 0; 745 if (ln->ln_expire) { 746 ln->ln_expire = time_second + 747 ND_IFINFO(ifp)->reachable; 748 } 749 } else { 750 if (lladdr && llchange) { 751 ln->ln_state = ND6_LLINFO_STALE; 752 ln->ln_expire = time_second + nd6_gctimer; 753 } 754 } 755 } 756 757 if (ln->ln_router && !is_router) { 758 /* 759 * The peer dropped the router flag. 760 * Remove the sender from the Default Router List and 761 * update the Destination Cache entries. 762 */ 763 struct nd_defrouter *dr; 764 struct in6_addr *in6; 765 766 in6 = &((struct sockaddr_in6 *)rt_key(rt))->sin6_addr; 767 768 /* 769 * Lock to protect the default router list. 770 * XXX: this might be unnecessary, since this function 771 * is only called under the network software interrupt 772 * context. However, we keep it just for safety. 773 */ 774 crit_enter(); 775 dr = defrouter_lookup(in6, rt->rt_ifp); 776 if (dr) 777 defrtrlist_del(dr); 778 else if (!ip6_forwarding && ip6_accept_rtadv) { 779 /* 780 * Even if the neighbor is not in the default 781 * router list, the neighbor may be used 782 * as a next hop for some destinations 783 * (e.g. redirect case). So we must 784 * call rt6_flush explicitly. 785 */ 786 rt6_flush(&ip6->ip6_src, rt->rt_ifp); 787 } 788 crit_exit(); 789 } 790 ln->ln_router = is_router; 791 } 792 rt->rt_flags &= ~RTF_REJECT; 793 ln->ln_asked = 0; 794 if (ln->ln_hold) { 795 /* 796 * we assume ifp is not a loopback here, so just set the 2nd 797 * argument as the 1st one. 798 */ 799 nd6_output(ifp, ifp, ln->ln_hold, 800 (struct sockaddr_in6 *)rt_key(rt), rt); 801 ln->ln_hold = 0; 802 } 803 804 freeit: 805 m_freem(m); 806 return; 807 808 bad: 809 icmp6stat.icp6s_badna++; 810 m_freem(m); 811 } 812 813 /* 814 * Neighbor advertisement output handling. 815 * 816 * Based on RFC 2461 817 * 818 * the following items are not implemented yet: 819 * - proxy advertisement delay rule (RFC2461 7.2.8, last paragraph, SHOULD) 820 * - anycast advertisement delay rule (RFC2461 7.2.7, SHOULD) 821 */ 822 void 823 nd6_na_output(struct ifnet *ifp, const struct in6_addr *daddr6, 824 const struct in6_addr *taddr6, u_long flags, 825 int tlladdr, /* 1 if include target link-layer address */ 826 struct sockaddr *sdl0) /* sockaddr_dl (= proxy NA) or NULL */ 827 { 828 struct mbuf *m; 829 struct ip6_hdr *ip6; 830 struct nd_neighbor_advert *nd_na; 831 struct in6_ifaddr *ia = NULL; 832 struct ip6_moptions im6o; 833 int icmp6len; 834 int maxlen; 835 caddr_t mac; 836 struct ifnet *outif = NULL; 837 838 /* estimate the size of message */ 839 maxlen = sizeof(*ip6) + sizeof(*nd_na); 840 maxlen += (sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7; 841 if (max_linkhdr + maxlen >= MCLBYTES) { 842 #ifdef DIAGNOSTIC 843 kprintf("nd6_na_output: max_linkhdr + maxlen >= MCLBYTES " 844 "(%d + %d > %d)\n", max_linkhdr, maxlen, MCLBYTES); 845 #endif 846 return; 847 } 848 849 m = m_getb(max_linkhdr + maxlen, MB_DONTWAIT, MT_DATA, M_PKTHDR); 850 if (m == NULL) 851 return; 852 853 if (IN6_IS_ADDR_MULTICAST(daddr6)) { 854 m->m_flags |= M_MCAST; 855 im6o.im6o_multicast_ifp = ifp; 856 im6o.im6o_multicast_hlim = 255; 857 im6o.im6o_multicast_loop = 0; 858 } 859 860 icmp6len = sizeof(*nd_na); 861 m->m_pkthdr.len = m->m_len = sizeof(struct ip6_hdr) + icmp6len; 862 m->m_data += max_linkhdr; /* or MH_ALIGN() equivalent? */ 863 864 /* fill neighbor advertisement packet */ 865 ip6 = mtod(m, struct ip6_hdr *); 866 ip6->ip6_flow = 0; 867 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 868 ip6->ip6_vfc |= IPV6_VERSION; 869 ip6->ip6_nxt = IPPROTO_ICMPV6; 870 ip6->ip6_hlim = 255; 871 if (IN6_IS_ADDR_UNSPECIFIED(daddr6)) { 872 /* reply to DAD */ 873 ip6->ip6_dst.s6_addr16[0] = IPV6_ADDR_INT16_MLL; 874 ip6->ip6_dst.s6_addr16[1] = htons(ifp->if_index); 875 ip6->ip6_dst.s6_addr32[1] = 0; 876 ip6->ip6_dst.s6_addr32[2] = 0; 877 ip6->ip6_dst.s6_addr32[3] = IPV6_ADDR_INT32_ONE; 878 flags &= ~ND_NA_FLAG_SOLICITED; 879 } else 880 ip6->ip6_dst = *daddr6; 881 882 /* 883 * Select a source whose scope is the same as that of the dest. 884 */ 885 ia = in6_ifawithifp(ifp, &ip6->ip6_dst); 886 if (ia == NULL) { 887 m_freem(m); 888 return; 889 } 890 ip6->ip6_src = ia->ia_addr.sin6_addr; 891 nd_na = (struct nd_neighbor_advert *)(ip6 + 1); 892 nd_na->nd_na_type = ND_NEIGHBOR_ADVERT; 893 nd_na->nd_na_code = 0; 894 nd_na->nd_na_target = *taddr6; 895 if (IN6_IS_SCOPE_LINKLOCAL(&nd_na->nd_na_target)) 896 nd_na->nd_na_target.s6_addr16[1] = 0; 897 898 /* 899 * "tlladdr" indicates NS's condition for adding tlladdr or not. 900 * see nd6_ns_input() for details. 901 * Basically, if NS packet is sent to unicast/anycast addr, 902 * target lladdr option SHOULD NOT be included. 903 */ 904 mac = NULL; 905 if (tlladdr) { 906 /* 907 * sdl0 != NULL indicates proxy NA. If we do proxy, use 908 * lladdr in sdl0. If we are not proxying (sending NA for 909 * my address) use lladdr configured for the interface. 910 */ 911 if (sdl0 == NULL) { 912 #ifdef CARP 913 if (ifp->if_carp) 914 mac = carp_macmatch6(ifp->if_carp, m, taddr6); 915 if (mac == NULL) 916 mac = nd6_ifptomac(ifp); 917 #else 918 mac = nd6_ifptomac(ifp); 919 #endif 920 } else if (sdl0->sa_family == AF_LINK) { 921 struct sockaddr_dl *sdl; 922 sdl = (struct sockaddr_dl *)sdl0; 923 if (sdl->sdl_alen == ifp->if_addrlen) 924 mac = LLADDR(sdl); 925 } 926 } 927 if (mac != NULL) { 928 int optlen = sizeof(struct nd_opt_hdr) + ifp->if_addrlen; 929 struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)(nd_na + 1); 930 931 /* roundup to 8 bytes alignment! */ 932 optlen = (optlen + 7) & ~7; 933 934 m->m_pkthdr.len += optlen; 935 m->m_len += optlen; 936 icmp6len += optlen; 937 bzero((caddr_t)nd_opt, optlen); 938 nd_opt->nd_opt_type = ND_OPT_TARGET_LINKADDR; 939 nd_opt->nd_opt_len = optlen >> 3; 940 bcopy(mac, (caddr_t)(nd_opt + 1), ifp->if_addrlen); 941 } else 942 flags &= ~ND_NA_FLAG_OVERRIDE; 943 944 ip6->ip6_plen = htons((u_short)icmp6len); 945 nd_na->nd_na_flags_reserved = flags; 946 nd_na->nd_na_cksum = 0; 947 nd_na->nd_na_cksum = 948 in6_cksum(m, IPPROTO_ICMPV6, sizeof(struct ip6_hdr), icmp6len); 949 950 ip6_output(m, NULL, NULL, 0, &im6o, &outif, NULL); 951 if (outif) { 952 icmp6_ifstat_inc(outif, ifs6_out_msg); 953 icmp6_ifstat_inc(outif, ifs6_out_neighboradvert); 954 } 955 icmp6stat.icp6s_outhist[ND_NEIGHBOR_ADVERT]++; 956 } 957 958 caddr_t 959 nd6_ifptomac(struct ifnet *ifp) 960 { 961 switch (ifp->if_type) { 962 case IFT_ETHER: 963 case IFT_IEEE1394: 964 #ifdef IFT_L2VLAN 965 case IFT_L2VLAN: 966 #endif 967 #ifdef IFT_IEEE80211 968 case IFT_IEEE80211: 969 #endif 970 #ifdef IFT_CARP 971 case IFT_CARP: 972 #endif 973 return ((caddr_t)(ifp + 1)); 974 break; 975 default: 976 return NULL; 977 } 978 } 979 980 TAILQ_HEAD(dadq_head, dadq); 981 struct dadq { 982 TAILQ_ENTRY(dadq) dad_list; 983 struct ifaddr *dad_ifa; 984 int dad_count; /* max NS to send */ 985 int dad_ns_tcount; /* # of trials to send NS */ 986 int dad_ns_ocount; /* NS sent so far */ 987 int dad_ns_icount; 988 int dad_na_icount; 989 struct callout dad_timer_ch; 990 }; 991 992 static struct dadq_head dadq; 993 static int dad_init = 0; 994 995 static struct dadq * 996 nd6_dad_find(struct ifaddr *ifa) 997 { 998 struct dadq *dp; 999 1000 TAILQ_FOREACH(dp, &dadq, dad_list) { 1001 if (dp->dad_ifa == ifa) 1002 return dp; 1003 } 1004 return NULL; 1005 } 1006 1007 static void 1008 nd6_dad_starttimer(struct dadq *dp, int ticks) 1009 { 1010 1011 callout_reset(&dp->dad_timer_ch, ticks, 1012 (void (*) (void *))nd6_dad_timer, (void *)dp->dad_ifa); 1013 } 1014 1015 static void 1016 nd6_dad_stoptimer(struct dadq *dp) 1017 { 1018 1019 callout_stop(&dp->dad_timer_ch); 1020 } 1021 1022 /* 1023 * Start Duplicated Address Detection (DAD) for specified interface address. 1024 */ 1025 void 1026 nd6_dad_start(struct ifaddr *ifa, 1027 int *tick) /* minimum delay ticks for IFF_UP event */ 1028 { 1029 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1030 struct dadq *dp; 1031 1032 if (!dad_init) { 1033 TAILQ_INIT(&dadq); 1034 dad_init++; 1035 } 1036 1037 /* 1038 * If we don't need DAD, don't do it. 1039 * There are several cases: 1040 * - DAD is disabled (ip6_dad_count == 0) 1041 * - the interface address is anycast 1042 */ 1043 if (!(ia->ia6_flags & IN6_IFF_TENTATIVE)) { 1044 log(LOG_DEBUG, 1045 "nd6_dad_start: called with non-tentative address " 1046 "%s(%s)\n", 1047 ip6_sprintf(&ia->ia_addr.sin6_addr), 1048 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1049 return; 1050 } 1051 if (ia->ia6_flags & IN6_IFF_ANYCAST) { 1052 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1053 return; 1054 } 1055 if (!ip6_dad_count) { 1056 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1057 return; 1058 } 1059 if (!ifa->ifa_ifp) 1060 panic("nd6_dad_start: ifa->ifa_ifp == NULL"); 1061 if (!(ifa->ifa_ifp->if_flags & IFF_UP)) 1062 return; 1063 if (nd6_dad_find(ifa) != NULL) { 1064 /* DAD already in progress */ 1065 return; 1066 } 1067 1068 dp = kmalloc(sizeof(*dp), M_IP6NDP, M_NOWAIT | M_ZERO); 1069 if (dp == NULL) { 1070 log(LOG_ERR, "nd6_dad_start: memory allocation failed for " 1071 "%s(%s)\n", 1072 ip6_sprintf(&ia->ia_addr.sin6_addr), 1073 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1074 return; 1075 } 1076 callout_init(&dp->dad_timer_ch); 1077 TAILQ_INSERT_TAIL(&dadq, (struct dadq *)dp, dad_list); 1078 1079 nd6log((LOG_DEBUG, "%s: starting DAD for %s\n", if_name(ifa->ifa_ifp), 1080 ip6_sprintf(&ia->ia_addr.sin6_addr))); 1081 1082 /* 1083 * Send NS packet for DAD, ip6_dad_count times. 1084 * Note that we must delay the first transmission, if this is the 1085 * first packet to be sent from the interface after interface 1086 * (re)initialization. 1087 */ 1088 dp->dad_ifa = ifa; 1089 crit_enter(); /* XXX MP not MP safe */ 1090 _IFAREF(ifa, 0); /* just for safety */ 1091 crit_exit(); 1092 dp->dad_count = ip6_dad_count; 1093 dp->dad_ns_icount = dp->dad_na_icount = 0; 1094 dp->dad_ns_ocount = dp->dad_ns_tcount = 0; 1095 if (tick == NULL) { 1096 nd6_dad_ns_output(dp, ifa); 1097 nd6_dad_starttimer(dp, 1098 ND_IFINFO(ifa->ifa_ifp)->retrans * hz / 1000); 1099 } else { 1100 int ntick; 1101 1102 if (*tick == 0) 1103 ntick = krandom() % (MAX_RTR_SOLICITATION_DELAY * hz); 1104 else 1105 ntick = *tick + krandom() % (hz / 2); 1106 *tick = ntick; 1107 nd6_dad_starttimer(dp, ntick); 1108 } 1109 } 1110 1111 /* 1112 * terminate DAD unconditionally. used for address removals. 1113 */ 1114 void 1115 nd6_dad_stop(struct ifaddr *ifa) 1116 { 1117 struct dadq *dp; 1118 1119 if (!dad_init) 1120 return; 1121 dp = nd6_dad_find(ifa); 1122 if (!dp) { 1123 /* DAD wasn't started yet */ 1124 return; 1125 } 1126 1127 nd6_dad_stoptimer(dp); 1128 1129 TAILQ_REMOVE(&dadq, (struct dadq *)dp, dad_list); 1130 kfree(dp, M_IP6NDP); 1131 dp = NULL; 1132 crit_enter(); /* XXX MP not MP safe */ 1133 _IFAFREE(ifa, 0); 1134 crit_exit(); 1135 } 1136 1137 static void 1138 nd6_dad_timer(struct ifaddr *ifa) 1139 { 1140 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1141 struct dadq *dp; 1142 1143 crit_enter(); /* XXX */ 1144 1145 /* Sanity check */ 1146 if (ia == NULL) { 1147 log(LOG_ERR, "nd6_dad_timer: called with null parameter\n"); 1148 goto done; 1149 } 1150 dp = nd6_dad_find(ifa); 1151 if (dp == NULL) { 1152 log(LOG_ERR, "nd6_dad_timer: DAD structure not found\n"); 1153 goto done; 1154 } 1155 if (ia->ia6_flags & IN6_IFF_DUPLICATED) { 1156 log(LOG_ERR, "nd6_dad_timer: called with duplicated address " 1157 "%s(%s)\n", 1158 ip6_sprintf(&ia->ia_addr.sin6_addr), 1159 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1160 goto done; 1161 } 1162 if (!(ia->ia6_flags & IN6_IFF_TENTATIVE)) { 1163 log(LOG_ERR, "nd6_dad_timer: called with non-tentative 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 1170 /* timeouted with IFF_{RUNNING,UP} check */ 1171 if (dp->dad_ns_tcount > dad_maxtry) { 1172 nd6log((LOG_INFO, "%s: could not run DAD, driver problem?\n", 1173 if_name(ifa->ifa_ifp))); 1174 1175 TAILQ_REMOVE(&dadq, (struct dadq *)dp, dad_list); 1176 kfree(dp, M_IP6NDP); 1177 dp = NULL; 1178 crit_enter(); /* XXX MP not MP safe */ 1179 _IFAFREE(ifa, 0); 1180 crit_exit(); 1181 goto done; 1182 } 1183 1184 /* Need more checks? */ 1185 if (dp->dad_ns_ocount < dp->dad_count) { 1186 /* 1187 * We have more NS to go. Send NS packet for DAD. 1188 */ 1189 nd6_dad_ns_output(dp, ifa); 1190 nd6_dad_starttimer(dp, 1191 ND_IFINFO(ifa->ifa_ifp)->retrans * hz / 1000); 1192 } else { 1193 /* 1194 * We have transmitted sufficient number of DAD packets. 1195 * See what we've got. 1196 */ 1197 int duplicate; 1198 1199 duplicate = 0; 1200 1201 if (dp->dad_na_icount) { 1202 /* 1203 * the check is in nd6_dad_na_input(), 1204 * but just in case 1205 */ 1206 duplicate++; 1207 } 1208 1209 if (dp->dad_ns_icount) { 1210 #if 0 /* heuristics */ 1211 /* 1212 * if 1213 * - we have sent many(?) DAD NS, and 1214 * - the number of NS we sent equals to the 1215 * number of NS we've got, and 1216 * - we've got no NA 1217 * we may have a faulty network card/driver which 1218 * loops back multicasts to myself. 1219 */ 1220 if (3 < dp->dad_count 1221 && dp->dad_ns_icount == dp->dad_count 1222 && dp->dad_na_icount == 0) { 1223 log(LOG_INFO, "DAD questionable for %s(%s): " 1224 "network card loops back multicast?\n", 1225 ip6_sprintf(&ia->ia_addr.sin6_addr), 1226 if_name(ifa->ifa_ifp)); 1227 /* XXX consider it a duplicate or not? */ 1228 /* duplicate++; */ 1229 } else { 1230 /* We've seen NS, means DAD has failed. */ 1231 duplicate++; 1232 } 1233 #else 1234 /* We've seen NS, means DAD has failed. */ 1235 duplicate++; 1236 #endif 1237 } 1238 1239 if (duplicate) { 1240 /* (*dp) will be freed in nd6_dad_duplicated() */ 1241 dp = NULL; 1242 nd6_dad_duplicated(ifa); 1243 } else { 1244 /* 1245 * We are done with DAD. No NA came, no NS came. 1246 * duplicated address found. 1247 */ 1248 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1249 1250 nd6log((LOG_DEBUG, 1251 "%s: DAD complete for %s - no duplicates found\n", 1252 if_name(ifa->ifa_ifp), 1253 ip6_sprintf(&ia->ia_addr.sin6_addr))); 1254 1255 TAILQ_REMOVE(&dadq, (struct dadq *)dp, dad_list); 1256 kfree(dp, M_IP6NDP); 1257 dp = NULL; 1258 _IFAFREE(ifa, 0); 1259 } 1260 } 1261 1262 done: 1263 crit_exit(); 1264 } 1265 1266 void 1267 nd6_dad_duplicated(struct ifaddr *ifa) 1268 { 1269 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1270 struct dadq *dp; 1271 1272 dp = nd6_dad_find(ifa); 1273 if (dp == NULL) { 1274 log(LOG_ERR, "nd6_dad_duplicated: DAD structure not found\n"); 1275 return; 1276 } 1277 1278 log(LOG_ERR, "%s: DAD detected duplicate IPv6 address %s: " 1279 "NS in/out=%d/%d, NA in=%d\n", 1280 if_name(ifa->ifa_ifp), ip6_sprintf(&ia->ia_addr.sin6_addr), 1281 dp->dad_ns_icount, dp->dad_ns_ocount, dp->dad_na_icount); 1282 1283 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1284 ia->ia6_flags |= IN6_IFF_DUPLICATED; 1285 1286 /* We are done with DAD, with duplicated address found. (failure) */ 1287 nd6_dad_stoptimer(dp); 1288 1289 log(LOG_ERR, "%s: DAD complete for %s - duplicate found\n", 1290 if_name(ifa->ifa_ifp), ip6_sprintf(&ia->ia_addr.sin6_addr)); 1291 log(LOG_ERR, "%s: manual intervention required\n", 1292 if_name(ifa->ifa_ifp)); 1293 1294 TAILQ_REMOVE(&dadq, (struct dadq *)dp, dad_list); 1295 kfree(dp, M_IP6NDP); 1296 dp = NULL; 1297 crit_enter(); /* XXX MP not MP safe */ 1298 _IFAFREE(ifa, 0); 1299 crit_exit(); 1300 } 1301 1302 static void 1303 nd6_dad_ns_output(struct dadq *dp, struct ifaddr *ifa) 1304 { 1305 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1306 struct ifnet *ifp = ifa->ifa_ifp; 1307 1308 dp->dad_ns_tcount++; 1309 if (!(ifp->if_flags & IFF_UP)) { 1310 #if 0 1311 kprintf("%s: interface down?\n", if_name(ifp)); 1312 #endif 1313 return; 1314 } 1315 if (!(ifp->if_flags & IFF_RUNNING)) { 1316 #if 0 1317 kprintf("%s: interface not running?\n", if_name(ifp)); 1318 #endif 1319 return; 1320 } 1321 1322 dp->dad_ns_ocount++; 1323 nd6_ns_output(ifp, NULL, &ia->ia_addr.sin6_addr, NULL, 1); 1324 } 1325 1326 static void 1327 nd6_dad_ns_input(struct ifaddr *ifa) 1328 { 1329 struct in6_ifaddr *ia; 1330 struct ifnet *ifp; 1331 const struct in6_addr *taddr6; 1332 struct dadq *dp; 1333 int duplicate; 1334 1335 if (!ifa) 1336 panic("ifa == NULL in nd6_dad_ns_input"); 1337 1338 ia = (struct in6_ifaddr *)ifa; 1339 ifp = ifa->ifa_ifp; 1340 taddr6 = &ia->ia_addr.sin6_addr; 1341 duplicate = 0; 1342 dp = nd6_dad_find(ifa); 1343 1344 /* Quickhack - completely ignore DAD NS packets */ 1345 if (dad_ignore_ns) { 1346 nd6log((LOG_INFO, 1347 "nd6_dad_ns_input: ignoring DAD NS packet for " 1348 "address %s(%s)\n", ip6_sprintf(taddr6), 1349 if_name(ifa->ifa_ifp))); 1350 return; 1351 } 1352 1353 /* 1354 * if I'm yet to start DAD, someone else started using this address 1355 * first. I have a duplicate and you win. 1356 */ 1357 if (!dp || dp->dad_ns_ocount == 0) 1358 duplicate++; 1359 1360 /* XXX more checks for loopback situation - see nd6_dad_timer too */ 1361 1362 if (duplicate) { 1363 dp = NULL; /* will be freed in nd6_dad_duplicated() */ 1364 nd6_dad_duplicated(ifa); 1365 } else { 1366 /* 1367 * not sure if I got a duplicate. 1368 * increment ns count and see what happens. 1369 */ 1370 if (dp) 1371 dp->dad_ns_icount++; 1372 } 1373 } 1374 1375 static void 1376 nd6_dad_na_input(struct ifaddr *ifa) 1377 { 1378 struct dadq *dp; 1379 1380 if (!ifa) 1381 panic("ifa == NULL in nd6_dad_na_input"); 1382 1383 dp = nd6_dad_find(ifa); 1384 if (dp) 1385 dp->dad_na_icount++; 1386 1387 /* remove the address. */ 1388 nd6_dad_duplicated(ifa); 1389 } 1390