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 1.24 2008/10/03 07:59:20 hasso 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 } else { 153 /* 154 * Make sure the source address is from a neighbor's address. 155 */ 156 if (in6ifa_ifplocaladdr(ifp, &saddr6) == NULL) { 157 nd6log((LOG_INFO, "nd6_ns_input: " 158 "NS packet from non-neighbor\n")); 159 goto bad; 160 } 161 } 162 163 if (IN6_IS_ADDR_MULTICAST(&taddr6)) { 164 nd6log((LOG_INFO, "nd6_ns_input: bad NS target (multicast)\n")); 165 goto bad; 166 } 167 168 if (IN6_IS_SCOPE_LINKLOCAL(&taddr6)) 169 taddr6.s6_addr16[1] = htons(ifp->if_index); 170 171 icmp6len -= sizeof(*nd_ns); 172 nd6_option_init(nd_ns + 1, icmp6len, &ndopts); 173 if (nd6_options(&ndopts) < 0) { 174 nd6log((LOG_INFO, 175 "nd6_ns_input: invalid ND option, ignored\n")); 176 /* nd6_options have incremented stats */ 177 goto freeit; 178 } 179 180 if (ndopts.nd_opts_src_lladdr) { 181 lladdr = (char *)(ndopts.nd_opts_src_lladdr + 1); 182 lladdrlen = ndopts.nd_opts_src_lladdr->nd_opt_len << 3; 183 } 184 185 if (IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_src) && lladdr) { 186 nd6log((LOG_INFO, "nd6_ns_input: bad DAD packet " 187 "(link-layer address option)\n")); 188 goto bad; 189 } 190 191 /* 192 * Attaching target link-layer address to the NA? 193 * (RFC 2461 7.2.4) 194 * 195 * NS IP dst is unicast/anycast MUST NOT add 196 * NS IP dst is solicited-node multicast MUST add 197 * 198 * In implementation, we add target link-layer address by default. 199 * We do not add one in MUST NOT cases. 200 */ 201 #if 0 /* too much! */ 202 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &daddr6); 203 if (ifa && (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_ANYCAST)) 204 tlladdr = 0; 205 else 206 #endif 207 if (!IN6_IS_ADDR_MULTICAST(&daddr6)) 208 tlladdr = 0; 209 else 210 tlladdr = 1; 211 212 /* 213 * Target address (taddr6) must be either: 214 * (1) Valid unicast/anycast address for my receiving interface, 215 * (2) Unicast address for which I'm offering proxy service, or 216 * (3) "tentative" address on which DAD is being performed. 217 */ 218 /* (1) and (3) check. */ 219 #ifdef CARP 220 if (ifp->if_carp) 221 ifa = carp_iamatch6(ifp->if_carp, &taddr6); 222 if (!ifa) 223 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &taddr6); 224 #else 225 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &taddr6); 226 #endif 227 228 /* (2) check. */ 229 if (!ifa) { 230 struct rtentry *rt; 231 struct sockaddr_in6 tsin6; 232 233 bzero(&tsin6, sizeof tsin6); 234 tsin6.sin6_len = sizeof(struct sockaddr_in6); 235 tsin6.sin6_family = AF_INET6; 236 tsin6.sin6_addr = taddr6; 237 238 rt = rtpurelookup((struct sockaddr *)&tsin6); 239 if (rt != NULL && (rt->rt_flags & RTF_ANNOUNCE) && 240 rt->rt_gateway->sa_family == AF_LINK) { 241 /* 242 * proxy NDP for single entry 243 */ 244 ifa = (struct ifaddr *)in6ifa_ifpforlinklocal(ifp, 245 IN6_IFF_NOTREADY|IN6_IFF_ANYCAST); 246 if (ifa) { 247 proxy = 1; 248 proxydl = SDL(rt->rt_gateway); 249 } 250 } 251 if (rt != NULL) 252 --rt->rt_refcnt; 253 } 254 if (ifa == NULL) { 255 /* 256 * We've got an NS packet, and we don't have that adddress 257 * assigned for us. We MUST silently ignore it. 258 * See RFC2461 7.2.3. 259 */ 260 goto freeit; 261 } 262 myaddr6 = *IFA_IN6(ifa); 263 anycast = ((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_ANYCAST; 264 tentative = ((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_TENTATIVE; 265 if (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_DUPLICATED) 266 goto freeit; 267 268 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) { 269 nd6log((LOG_INFO, 270 "nd6_ns_input: lladdrlen mismatch for %s " 271 "(if %d, NS packet %d)\n", 272 ip6_sprintf(&taddr6), ifp->if_addrlen, lladdrlen - 2)); 273 goto bad; 274 } 275 276 if (IN6_ARE_ADDR_EQUAL(&myaddr6, &saddr6)) { 277 nd6log((LOG_INFO, 278 "nd6_ns_input: duplicate IP6 address %s\n", 279 ip6_sprintf(&saddr6))); 280 goto freeit; 281 } 282 283 /* 284 * We have neighbor solicitation packet, with target address equals to 285 * one of my tentative address. 286 * 287 * src addr how to process? 288 * --- --- 289 * multicast of course, invalid (rejected in ip6_input) 290 * unicast somebody is doing address resolution -> ignore 291 * unspec dup address detection 292 * 293 * The processing is defined in RFC 2462. 294 */ 295 if (tentative) { 296 /* 297 * If source address is unspecified address, it is for 298 * duplicated address detection. 299 * 300 * If not, the packet is for addess resolution; 301 * silently ignore it. 302 */ 303 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) 304 nd6_dad_ns_input(ifa); 305 306 goto freeit; 307 } 308 309 /* 310 * If the source address is unspecified address, entries must not 311 * be created or updated. 312 * It looks that sender is performing DAD. Output NA toward 313 * all-node multicast address, to tell the sender that I'm using 314 * the address. 315 * S bit ("solicited") must be zero. 316 */ 317 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) { 318 saddr6 = kin6addr_linklocal_allnodes; 319 saddr6.s6_addr16[1] = htons(ifp->if_index); 320 nd6_na_output(ifp, &saddr6, &taddr6, 321 ((anycast || proxy || !tlladdr) 322 ? 0 : ND_NA_FLAG_OVERRIDE) 323 | (ip6_forwarding ? ND_NA_FLAG_ROUTER : 0), 324 tlladdr, (struct sockaddr *)proxydl); 325 goto freeit; 326 } 327 328 nd6_cache_lladdr(ifp, &saddr6, lladdr, lladdrlen, ND_NEIGHBOR_SOLICIT, 0); 329 330 nd6_na_output(ifp, &saddr6, &taddr6, 331 ((anycast || proxy || !tlladdr) ? 0 : ND_NA_FLAG_OVERRIDE) 332 | (ip6_forwarding ? ND_NA_FLAG_ROUTER : 0) 333 | ND_NA_FLAG_SOLICITED, 334 tlladdr, (struct sockaddr *)proxydl); 335 freeit: 336 m_freem(m); 337 return; 338 339 bad: 340 nd6log((LOG_ERR, "nd6_ns_input: src=%s\n", ip6_sprintf(&saddr6))); 341 nd6log((LOG_ERR, "nd6_ns_input: dst=%s\n", ip6_sprintf(&daddr6))); 342 nd6log((LOG_ERR, "nd6_ns_input: tgt=%s\n", ip6_sprintf(&taddr6))); 343 icmp6stat.icp6s_badns++; 344 m_freem(m); 345 } 346 347 /* 348 * Output an Neighbor Solicitation Message. Caller specifies: 349 * - ICMP6 header source IP6 address 350 * - ND6 header target IP6 address 351 * - ND6 header source datalink address 352 * 353 * Based on RFC 2461 354 * Based on RFC 2462 (duplicated address detection) 355 */ 356 void 357 nd6_ns_output(struct ifnet *ifp, const struct in6_addr *daddr6, 358 const struct in6_addr *taddr6, 359 struct llinfo_nd6 *ln, /* for source address determination */ 360 int dad) /* duplicated address detection */ 361 { 362 struct mbuf *m; 363 struct ip6_hdr *ip6; 364 struct nd_neighbor_solicit *nd_ns; 365 struct in6_ifaddr *ia = NULL; 366 struct ip6_moptions im6o; 367 int icmp6len; 368 int maxlen; 369 caddr_t mac; 370 struct ifnet *outif = NULL; 371 372 if (IN6_IS_ADDR_MULTICAST(taddr6)) 373 return; 374 375 /* estimate the size of message */ 376 maxlen = sizeof(*ip6) + sizeof(*nd_ns); 377 maxlen += (sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7; 378 if (max_linkhdr + maxlen >= MCLBYTES) { 379 #ifdef DIAGNOSTIC 380 kprintf("nd6_ns_output: max_linkhdr + maxlen >= MCLBYTES " 381 "(%d + %d > %d)\n", max_linkhdr, maxlen, MCLBYTES); 382 #endif 383 return; 384 } 385 386 m = m_getb(max_linkhdr + maxlen, MB_DONTWAIT, MT_DATA, M_PKTHDR); 387 if (m == NULL) 388 return; 389 390 if (daddr6 == NULL || IN6_IS_ADDR_MULTICAST(daddr6)) { 391 m->m_flags |= M_MCAST; 392 im6o.im6o_multicast_ifp = ifp; 393 im6o.im6o_multicast_hlim = 255; 394 im6o.im6o_multicast_loop = 0; 395 } 396 397 icmp6len = sizeof(*nd_ns); 398 m->m_pkthdr.len = m->m_len = sizeof(*ip6) + icmp6len; 399 m->m_data += max_linkhdr; /* or MH_ALIGN() equivalent? */ 400 401 /* fill neighbor solicitation packet */ 402 ip6 = mtod(m, struct ip6_hdr *); 403 ip6->ip6_flow = 0; 404 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 405 ip6->ip6_vfc |= IPV6_VERSION; 406 /* ip6->ip6_plen will be set later */ 407 ip6->ip6_nxt = IPPROTO_ICMPV6; 408 ip6->ip6_hlim = 255; 409 if (daddr6) 410 ip6->ip6_dst = *daddr6; 411 else { 412 ip6->ip6_dst.s6_addr16[0] = IPV6_ADDR_INT16_MLL; 413 ip6->ip6_dst.s6_addr16[1] = htons(ifp->if_index); 414 ip6->ip6_dst.s6_addr32[1] = 0; 415 ip6->ip6_dst.s6_addr32[2] = IPV6_ADDR_INT32_ONE; 416 ip6->ip6_dst.s6_addr32[3] = taddr6->s6_addr32[3]; 417 ip6->ip6_dst.s6_addr8[12] = 0xff; 418 } 419 if (!dad) { 420 #if 0 /* KAME way, exact address scope match */ 421 /* 422 * Select a source whose scope is the same as that of the dest. 423 * Typically, the dest is link-local solicitation multicast 424 * (i.e. neighbor discovery) or link-local/global unicast 425 * (i.e. neighbor un-reachability detection). 426 */ 427 ia = in6_ifawithifp(ifp, &ip6->ip6_dst); 428 if (ia == NULL) { 429 m_freem(m); 430 return; 431 } 432 ip6->ip6_src = ia->ia_addr.sin6_addr; 433 #else /* spec-wise correct */ 434 /* 435 * RFC2461 7.2.2: 436 * "If the source address of the packet prompting the 437 * solicitation is the same as one of the addresses assigned 438 * to the outgoing interface, that address SHOULD be placed 439 * in the IP Source Address of the outgoing solicitation. 440 * Otherwise, any one of the addresses assigned to the 441 * interface should be used." 442 * 443 * We use the source address for the prompting packet 444 * (saddr6), if: 445 * - saddr6 is given from the caller (by giving "ln"), and 446 * - saddr6 belongs to the outgoing interface. 447 * Otherwise, we perform a scope-wise match. 448 */ 449 struct ip6_hdr *hip6; /* hold ip6 */ 450 struct in6_addr *saddr6; 451 452 if (ln && ln->ln_hold) { 453 hip6 = mtod(ln->ln_hold, struct ip6_hdr *); 454 /* XXX pullup? */ 455 if (sizeof(*hip6) < ln->ln_hold->m_len) 456 saddr6 = &hip6->ip6_src; 457 else 458 saddr6 = NULL; 459 } else 460 saddr6 = NULL; 461 if (saddr6 && in6ifa_ifpwithaddr(ifp, saddr6)) 462 bcopy(saddr6, &ip6->ip6_src, sizeof(*saddr6)); 463 else { 464 ia = in6_ifawithifp(ifp, &ip6->ip6_dst); 465 if (ia == NULL) { 466 m_freem(m); 467 return; 468 } 469 ip6->ip6_src = ia->ia_addr.sin6_addr; 470 } 471 #endif 472 } else { 473 /* 474 * Source address for DAD packet must always be IPv6 475 * unspecified address. (0::0) 476 */ 477 bzero(&ip6->ip6_src, sizeof(ip6->ip6_src)); 478 } 479 nd_ns = (struct nd_neighbor_solicit *)(ip6 + 1); 480 nd_ns->nd_ns_type = ND_NEIGHBOR_SOLICIT; 481 nd_ns->nd_ns_code = 0; 482 nd_ns->nd_ns_reserved = 0; 483 nd_ns->nd_ns_target = *taddr6; 484 485 if (IN6_IS_SCOPE_LINKLOCAL(&nd_ns->nd_ns_target)) 486 nd_ns->nd_ns_target.s6_addr16[1] = 0; 487 488 /* 489 * Add source link-layer address option. 490 * 491 * spec implementation 492 * --- --- 493 * DAD packet MUST NOT do not add the option 494 * there's no link layer address: 495 * impossible do not add the option 496 * there's link layer address: 497 * Multicast NS MUST add one add the option 498 * Unicast NS SHOULD add one add the option 499 */ 500 if (!dad && (mac = nd6_ifptomac(ifp))) { 501 int optlen = sizeof(struct nd_opt_hdr) + ifp->if_addrlen; 502 struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)(nd_ns + 1); 503 /* 8 byte alignments... */ 504 optlen = (optlen + 7) & ~7; 505 506 m->m_pkthdr.len += optlen; 507 m->m_len += optlen; 508 icmp6len += optlen; 509 bzero((caddr_t)nd_opt, optlen); 510 nd_opt->nd_opt_type = ND_OPT_SOURCE_LINKADDR; 511 nd_opt->nd_opt_len = optlen >> 3; 512 bcopy(mac, (caddr_t)(nd_opt + 1), ifp->if_addrlen); 513 } 514 515 ip6->ip6_plen = htons((u_short)icmp6len); 516 nd_ns->nd_ns_cksum = 0; 517 nd_ns->nd_ns_cksum 518 = in6_cksum(m, IPPROTO_ICMPV6, sizeof(*ip6), icmp6len); 519 520 ip6_output(m, NULL, NULL, dad ? IPV6_DADOUTPUT : 0, &im6o, &outif, NULL); 521 if (outif) { 522 icmp6_ifstat_inc(outif, ifs6_out_msg); 523 icmp6_ifstat_inc(outif, ifs6_out_neighborsolicit); 524 } 525 icmp6stat.icp6s_outhist[ND_NEIGHBOR_SOLICIT]++; 526 } 527 528 /* 529 * Neighbor advertisement input handling. 530 * 531 * Based on RFC 2461 532 * Based on RFC 2462 (duplicated address detection) 533 * 534 * the following items are not implemented yet: 535 * - proxy advertisement delay rule (RFC2461 7.2.8, last paragraph, SHOULD) 536 * - anycast advertisement delay rule (RFC2461 7.2.7, SHOULD) 537 */ 538 void 539 nd6_na_input(struct mbuf *m, int off, int icmp6len) 540 { 541 struct ifnet *ifp = m->m_pkthdr.rcvif; 542 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 543 struct nd_neighbor_advert *nd_na; 544 struct in6_addr saddr6 = ip6->ip6_src; 545 struct in6_addr daddr6 = ip6->ip6_dst; 546 struct in6_addr taddr6; 547 int flags; 548 int is_router; 549 int is_solicited; 550 int is_override; 551 char *lladdr = NULL; 552 int lladdrlen = 0; 553 struct ifaddr *ifa; 554 struct llinfo_nd6 *ln; 555 struct rtentry *rt; 556 struct sockaddr_dl *sdl; 557 union nd_opts ndopts; 558 559 if (ip6->ip6_hlim != 255) { 560 nd6log((LOG_ERR, 561 "nd6_na_input: invalid hlim (%d) from %s to %s on %s\n", 562 ip6->ip6_hlim, ip6_sprintf(&ip6->ip6_src), 563 ip6_sprintf(&ip6->ip6_dst), if_name(ifp))); 564 goto bad; 565 } 566 567 #ifndef PULLDOWN_TEST 568 IP6_EXTHDR_CHECK(m, off, icmp6len,); 569 nd_na = (struct nd_neighbor_advert *)((caddr_t)ip6 + off); 570 #else 571 IP6_EXTHDR_GET(nd_na, struct nd_neighbor_advert *, m, off, icmp6len); 572 if (nd_na == NULL) { 573 icmp6stat.icp6s_tooshort++; 574 return; 575 } 576 #endif 577 taddr6 = nd_na->nd_na_target; 578 flags = nd_na->nd_na_flags_reserved; 579 is_router = ((flags & ND_NA_FLAG_ROUTER) != 0); 580 is_solicited = ((flags & ND_NA_FLAG_SOLICITED) != 0); 581 is_override = ((flags & ND_NA_FLAG_OVERRIDE) != 0); 582 583 if (IN6_IS_SCOPE_LINKLOCAL(&taddr6)) 584 taddr6.s6_addr16[1] = htons(ifp->if_index); 585 586 if (IN6_IS_ADDR_MULTICAST(&taddr6)) { 587 nd6log((LOG_ERR, 588 "nd6_na_input: invalid target address %s\n", 589 ip6_sprintf(&taddr6))); 590 goto bad; 591 } 592 if (IN6_IS_ADDR_MULTICAST(&daddr6)) 593 if (is_solicited) { 594 nd6log((LOG_ERR, 595 "nd6_na_input: a solicited adv is multicasted\n")); 596 goto bad; 597 } 598 599 icmp6len -= sizeof(*nd_na); 600 nd6_option_init(nd_na + 1, icmp6len, &ndopts); 601 if (nd6_options(&ndopts) < 0) { 602 nd6log((LOG_INFO, 603 "nd6_na_input: invalid ND option, ignored\n")); 604 /* nd6_options have incremented stats */ 605 goto freeit; 606 } 607 608 if (ndopts.nd_opts_tgt_lladdr) { 609 lladdr = (char *)(ndopts.nd_opts_tgt_lladdr + 1); 610 lladdrlen = ndopts.nd_opts_tgt_lladdr->nd_opt_len << 3; 611 } 612 613 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &taddr6); 614 615 /* 616 * Target address matches one of my interface address. 617 * 618 * If my address is tentative, this means that there's somebody 619 * already using the same address as mine. This indicates DAD failure. 620 * This is defined in RFC 2462. 621 * 622 * Otherwise, process as defined in RFC 2461. 623 */ 624 if (ifa 625 && (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_TENTATIVE)) { 626 nd6_dad_na_input(ifa); 627 goto freeit; 628 } 629 630 /* Just for safety, maybe unnecessary. */ 631 if (ifa) { 632 log(LOG_ERR, 633 "nd6_na_input: duplicate IP6 address %s\n", 634 ip6_sprintf(&taddr6)); 635 goto freeit; 636 } 637 638 /* 639 * Make sure the source address is from a neighbor's address. 640 */ 641 if (in6ifa_ifplocaladdr(ifp, &saddr6) == NULL) { 642 nd6log((LOG_INFO, "nd6_na_input: " 643 "NA packet from non-neighbor\n")); 644 goto bad; 645 } 646 647 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) { 648 nd6log((LOG_INFO, 649 "nd6_na_input: lladdrlen mismatch for %s " 650 "(if %d, NA packet %d)\n", 651 ip6_sprintf(&taddr6), ifp->if_addrlen, lladdrlen - 2)); 652 goto bad; 653 } 654 655 /* 656 * If no neighbor cache entry is found, NA SHOULD silently be discarded. 657 */ 658 rt = nd6_lookup(&taddr6, 0, ifp); 659 if ((rt == NULL) || 660 ((ln = (struct llinfo_nd6 *)rt->rt_llinfo) == NULL) || 661 ((sdl = SDL(rt->rt_gateway)) == NULL)) 662 goto freeit; 663 664 if (ln->ln_state == ND6_LLINFO_INCOMPLETE) { 665 /* 666 * If the link-layer has address, and no lladdr option came, 667 * discard the packet. 668 */ 669 if (ifp->if_addrlen && !lladdr) 670 goto freeit; 671 672 /* 673 * Record link-layer address, and update the state. 674 */ 675 sdl->sdl_alen = ifp->if_addrlen; 676 bcopy(lladdr, LLADDR(sdl), ifp->if_addrlen); 677 if (is_solicited) { 678 ln->ln_state = ND6_LLINFO_REACHABLE; 679 ln->ln_byhint = 0; 680 if (ln->ln_expire) 681 ln->ln_expire = time_second + 682 ND_IFINFO(rt->rt_ifp)->reachable; 683 } else { 684 ln->ln_state = ND6_LLINFO_STALE; 685 ln->ln_expire = time_second + nd6_gctimer; 686 } 687 if ((ln->ln_router = is_router) != 0) { 688 /* 689 * This means a router's state has changed from 690 * non-reachable to probably reachable, and might 691 * affect the status of associated prefixes.. 692 */ 693 pfxlist_onlink_check(); 694 } 695 } else { 696 int llchange; 697 698 /* 699 * Check if the link-layer address has changed or not. 700 */ 701 if (!lladdr) 702 llchange = 0; 703 else { 704 if (sdl->sdl_alen) { 705 if (bcmp(lladdr, LLADDR(sdl), ifp->if_addrlen)) 706 llchange = 1; 707 else 708 llchange = 0; 709 } else 710 llchange = 1; 711 } 712 713 /* 714 * This is VERY complex. Look at it with care. 715 * 716 * override solicit lladdr llchange action 717 * (L: record lladdr) 718 * 719 * 0 0 n -- (2c) 720 * 0 0 y n (2b) L 721 * 0 0 y y (1) REACHABLE->STALE 722 * 0 1 n -- (2c) *->REACHABLE 723 * 0 1 y n (2b) L *->REACHABLE 724 * 0 1 y y (1) REACHABLE->STALE 725 * 1 0 n -- (2a) 726 * 1 0 y n (2a) L 727 * 1 0 y y (2a) L *->STALE 728 * 1 1 n -- (2a) *->REACHABLE 729 * 1 1 y n (2a) L *->REACHABLE 730 * 1 1 y y (2a) L *->REACHABLE 731 */ 732 if (!is_override && (lladdr && llchange)) { /* (1) */ 733 /* 734 * If state is REACHABLE, make it STALE. 735 * no other updates should be done. 736 */ 737 if (ln->ln_state == ND6_LLINFO_REACHABLE) { 738 ln->ln_state = ND6_LLINFO_STALE; 739 ln->ln_expire = time_second + nd6_gctimer; 740 } 741 goto freeit; 742 } else if (is_override /* (2a) */ 743 || (!is_override && (lladdr && !llchange)) /* (2b) */ 744 || !lladdr) { /* (2c) */ 745 /* 746 * Update link-local address, if any. 747 */ 748 if (lladdr) { 749 sdl->sdl_alen = ifp->if_addrlen; 750 bcopy(lladdr, LLADDR(sdl), ifp->if_addrlen); 751 } 752 753 /* 754 * If solicited, make the state REACHABLE. 755 * If not solicited and the link-layer address was 756 * changed, make it STALE. 757 */ 758 if (is_solicited) { 759 ln->ln_state = ND6_LLINFO_REACHABLE; 760 ln->ln_byhint = 0; 761 if (ln->ln_expire) { 762 ln->ln_expire = time_second + 763 ND_IFINFO(ifp)->reachable; 764 } 765 } else { 766 if (lladdr && llchange) { 767 ln->ln_state = ND6_LLINFO_STALE; 768 ln->ln_expire = time_second + nd6_gctimer; 769 } 770 } 771 } 772 773 if (ln->ln_router && !is_router) { 774 /* 775 * The peer dropped the router flag. 776 * Remove the sender from the Default Router List and 777 * update the Destination Cache entries. 778 */ 779 struct nd_defrouter *dr; 780 struct in6_addr *in6; 781 782 in6 = &((struct sockaddr_in6 *)rt_key(rt))->sin6_addr; 783 784 /* 785 * Lock to protect the default router list. 786 * XXX: this might be unnecessary, since this function 787 * is only called under the network software interrupt 788 * context. However, we keep it just for safety. 789 */ 790 crit_enter(); 791 dr = defrouter_lookup(in6, rt->rt_ifp); 792 if (dr) 793 defrtrlist_del(dr); 794 else if (!ip6_forwarding && ip6_accept_rtadv) { 795 /* 796 * Even if the neighbor is not in the default 797 * router list, the neighbor may be used 798 * as a next hop for some destinations 799 * (e.g. redirect case). So we must 800 * call rt6_flush explicitly. 801 */ 802 rt6_flush(&ip6->ip6_src, rt->rt_ifp); 803 } 804 crit_exit(); 805 } 806 ln->ln_router = is_router; 807 } 808 rt->rt_flags &= ~RTF_REJECT; 809 ln->ln_asked = 0; 810 if (ln->ln_hold) { 811 /* 812 * we assume ifp is not a loopback here, so just set the 2nd 813 * argument as the 1st one. 814 */ 815 nd6_output(ifp, ifp, ln->ln_hold, 816 (struct sockaddr_in6 *)rt_key(rt), rt); 817 ln->ln_hold = 0; 818 } 819 820 freeit: 821 m_freem(m); 822 return; 823 824 bad: 825 icmp6stat.icp6s_badna++; 826 m_freem(m); 827 } 828 829 /* 830 * Neighbor advertisement output handling. 831 * 832 * Based on RFC 2461 833 * 834 * the following items are not implemented yet: 835 * - proxy advertisement delay rule (RFC2461 7.2.8, last paragraph, SHOULD) 836 * - anycast advertisement delay rule (RFC2461 7.2.7, SHOULD) 837 */ 838 void 839 nd6_na_output(struct ifnet *ifp, const struct in6_addr *daddr6, 840 const struct in6_addr *taddr6, u_long flags, 841 int tlladdr, /* 1 if include target link-layer address */ 842 struct sockaddr *sdl0) /* sockaddr_dl (= proxy NA) or NULL */ 843 { 844 struct mbuf *m; 845 struct ip6_hdr *ip6; 846 struct nd_neighbor_advert *nd_na; 847 struct in6_ifaddr *ia = NULL; 848 struct ip6_moptions im6o; 849 int icmp6len; 850 int maxlen; 851 caddr_t mac; 852 struct ifnet *outif = NULL; 853 854 /* estimate the size of message */ 855 maxlen = sizeof(*ip6) + sizeof(*nd_na); 856 maxlen += (sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7; 857 if (max_linkhdr + maxlen >= MCLBYTES) { 858 #ifdef DIAGNOSTIC 859 kprintf("nd6_na_output: max_linkhdr + maxlen >= MCLBYTES " 860 "(%d + %d > %d)\n", max_linkhdr, maxlen, MCLBYTES); 861 #endif 862 return; 863 } 864 865 m = m_getb(max_linkhdr + maxlen, MB_DONTWAIT, MT_DATA, M_PKTHDR); 866 if (m == NULL) 867 return; 868 869 if (IN6_IS_ADDR_MULTICAST(daddr6)) { 870 m->m_flags |= M_MCAST; 871 im6o.im6o_multicast_ifp = ifp; 872 im6o.im6o_multicast_hlim = 255; 873 im6o.im6o_multicast_loop = 0; 874 } 875 876 icmp6len = sizeof(*nd_na); 877 m->m_pkthdr.len = m->m_len = sizeof(struct ip6_hdr) + icmp6len; 878 m->m_data += max_linkhdr; /* or MH_ALIGN() equivalent? */ 879 880 /* fill neighbor advertisement packet */ 881 ip6 = mtod(m, struct ip6_hdr *); 882 ip6->ip6_flow = 0; 883 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 884 ip6->ip6_vfc |= IPV6_VERSION; 885 ip6->ip6_nxt = IPPROTO_ICMPV6; 886 ip6->ip6_hlim = 255; 887 if (IN6_IS_ADDR_UNSPECIFIED(daddr6)) { 888 /* reply to DAD */ 889 ip6->ip6_dst.s6_addr16[0] = IPV6_ADDR_INT16_MLL; 890 ip6->ip6_dst.s6_addr16[1] = htons(ifp->if_index); 891 ip6->ip6_dst.s6_addr32[1] = 0; 892 ip6->ip6_dst.s6_addr32[2] = 0; 893 ip6->ip6_dst.s6_addr32[3] = IPV6_ADDR_INT32_ONE; 894 flags &= ~ND_NA_FLAG_SOLICITED; 895 } else 896 ip6->ip6_dst = *daddr6; 897 898 /* 899 * Select a source whose scope is the same as that of the dest. 900 */ 901 ia = in6_ifawithifp(ifp, &ip6->ip6_dst); 902 if (ia == NULL) { 903 m_freem(m); 904 return; 905 } 906 ip6->ip6_src = ia->ia_addr.sin6_addr; 907 nd_na = (struct nd_neighbor_advert *)(ip6 + 1); 908 nd_na->nd_na_type = ND_NEIGHBOR_ADVERT; 909 nd_na->nd_na_code = 0; 910 nd_na->nd_na_target = *taddr6; 911 if (IN6_IS_SCOPE_LINKLOCAL(&nd_na->nd_na_target)) 912 nd_na->nd_na_target.s6_addr16[1] = 0; 913 914 /* 915 * "tlladdr" indicates NS's condition for adding tlladdr or not. 916 * see nd6_ns_input() for details. 917 * Basically, if NS packet is sent to unicast/anycast addr, 918 * target lladdr option SHOULD NOT be included. 919 */ 920 mac = NULL; 921 if (tlladdr) { 922 /* 923 * sdl0 != NULL indicates proxy NA. If we do proxy, use 924 * lladdr in sdl0. If we are not proxying (sending NA for 925 * my address) use lladdr configured for the interface. 926 */ 927 if (sdl0 == NULL) { 928 #ifdef CARP 929 if (ifp->if_carp) 930 mac = carp_macmatch6(ifp->if_carp, m, taddr6); 931 if (mac == NULL) 932 mac = nd6_ifptomac(ifp); 933 #else 934 mac = nd6_ifptomac(ifp); 935 #endif 936 } else if (sdl0->sa_family == AF_LINK) { 937 struct sockaddr_dl *sdl; 938 sdl = (struct sockaddr_dl *)sdl0; 939 if (sdl->sdl_alen == ifp->if_addrlen) 940 mac = LLADDR(sdl); 941 } 942 } 943 if (mac != NULL) { 944 int optlen = sizeof(struct nd_opt_hdr) + ifp->if_addrlen; 945 struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)(nd_na + 1); 946 947 /* roundup to 8 bytes alignment! */ 948 optlen = (optlen + 7) & ~7; 949 950 m->m_pkthdr.len += optlen; 951 m->m_len += optlen; 952 icmp6len += optlen; 953 bzero((caddr_t)nd_opt, optlen); 954 nd_opt->nd_opt_type = ND_OPT_TARGET_LINKADDR; 955 nd_opt->nd_opt_len = optlen >> 3; 956 bcopy(mac, (caddr_t)(nd_opt + 1), ifp->if_addrlen); 957 } else 958 flags &= ~ND_NA_FLAG_OVERRIDE; 959 960 ip6->ip6_plen = htons((u_short)icmp6len); 961 nd_na->nd_na_flags_reserved = flags; 962 nd_na->nd_na_cksum = 0; 963 nd_na->nd_na_cksum = 964 in6_cksum(m, IPPROTO_ICMPV6, sizeof(struct ip6_hdr), icmp6len); 965 966 ip6_output(m, NULL, NULL, 0, &im6o, &outif, NULL); 967 if (outif) { 968 icmp6_ifstat_inc(outif, ifs6_out_msg); 969 icmp6_ifstat_inc(outif, ifs6_out_neighboradvert); 970 } 971 icmp6stat.icp6s_outhist[ND_NEIGHBOR_ADVERT]++; 972 } 973 974 caddr_t 975 nd6_ifptomac(struct ifnet *ifp) 976 { 977 switch (ifp->if_type) { 978 case IFT_ETHER: 979 case IFT_IEEE1394: 980 #ifdef IFT_L2VLAN 981 case IFT_L2VLAN: 982 #endif 983 #ifdef IFT_IEEE80211 984 case IFT_IEEE80211: 985 #endif 986 #ifdef IFT_CARP 987 case IFT_CARP: 988 #endif 989 return ((caddr_t)(ifp + 1)); 990 break; 991 default: 992 return NULL; 993 } 994 } 995 996 TAILQ_HEAD(dadq_head, dadq); 997 struct dadq { 998 TAILQ_ENTRY(dadq) dad_list; 999 struct ifaddr *dad_ifa; 1000 int dad_count; /* max NS to send */ 1001 int dad_ns_tcount; /* # of trials to send NS */ 1002 int dad_ns_ocount; /* NS sent so far */ 1003 int dad_ns_icount; 1004 int dad_na_icount; 1005 struct callout dad_timer_ch; 1006 }; 1007 1008 static struct dadq_head dadq; 1009 static int dad_init = 0; 1010 1011 static struct dadq * 1012 nd6_dad_find(struct ifaddr *ifa) 1013 { 1014 struct dadq *dp; 1015 1016 TAILQ_FOREACH(dp, &dadq, dad_list) { 1017 if (dp->dad_ifa == ifa) 1018 return dp; 1019 } 1020 return NULL; 1021 } 1022 1023 static void 1024 nd6_dad_starttimer(struct dadq *dp, int ticks) 1025 { 1026 1027 callout_reset(&dp->dad_timer_ch, ticks, 1028 (void (*) (void *))nd6_dad_timer, (void *)dp->dad_ifa); 1029 } 1030 1031 static void 1032 nd6_dad_stoptimer(struct dadq *dp) 1033 { 1034 1035 callout_stop(&dp->dad_timer_ch); 1036 } 1037 1038 /* 1039 * Start Duplicated Address Detection (DAD) for specified interface address. 1040 */ 1041 void 1042 nd6_dad_start(struct ifaddr *ifa, 1043 int *tick) /* minimum delay ticks for IFF_UP event */ 1044 { 1045 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1046 struct dadq *dp; 1047 1048 if (!dad_init) { 1049 TAILQ_INIT(&dadq); 1050 dad_init++; 1051 } 1052 1053 /* 1054 * If we don't need DAD, don't do it. 1055 * There are several cases: 1056 * - DAD is disabled (ip6_dad_count == 0) 1057 * - the interface address is anycast 1058 */ 1059 if (!(ia->ia6_flags & IN6_IFF_TENTATIVE)) { 1060 log(LOG_DEBUG, 1061 "nd6_dad_start: called with non-tentative address " 1062 "%s(%s)\n", 1063 ip6_sprintf(&ia->ia_addr.sin6_addr), 1064 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1065 return; 1066 } 1067 if (ia->ia6_flags & IN6_IFF_ANYCAST) { 1068 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1069 return; 1070 } 1071 if (!ip6_dad_count) { 1072 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1073 return; 1074 } 1075 if (!ifa->ifa_ifp) 1076 panic("nd6_dad_start: ifa->ifa_ifp == NULL"); 1077 if (!(ifa->ifa_ifp->if_flags & IFF_UP)) 1078 return; 1079 if (nd6_dad_find(ifa) != NULL) { 1080 /* DAD already in progress */ 1081 return; 1082 } 1083 1084 dp = kmalloc(sizeof(*dp), M_IP6NDP, M_NOWAIT | M_ZERO); 1085 if (dp == NULL) { 1086 log(LOG_ERR, "nd6_dad_start: memory allocation failed for " 1087 "%s(%s)\n", 1088 ip6_sprintf(&ia->ia_addr.sin6_addr), 1089 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1090 return; 1091 } 1092 callout_init(&dp->dad_timer_ch); 1093 TAILQ_INSERT_TAIL(&dadq, (struct dadq *)dp, dad_list); 1094 1095 nd6log((LOG_DEBUG, "%s: starting DAD for %s\n", if_name(ifa->ifa_ifp), 1096 ip6_sprintf(&ia->ia_addr.sin6_addr))); 1097 1098 /* 1099 * Send NS packet for DAD, ip6_dad_count times. 1100 * Note that we must delay the first transmission, if this is the 1101 * first packet to be sent from the interface after interface 1102 * (re)initialization. 1103 */ 1104 dp->dad_ifa = ifa; 1105 crit_enter(); /* XXX MP not MP safe */ 1106 _IFAREF(ifa, 0); /* just for safety */ 1107 crit_exit(); 1108 dp->dad_count = ip6_dad_count; 1109 dp->dad_ns_icount = dp->dad_na_icount = 0; 1110 dp->dad_ns_ocount = dp->dad_ns_tcount = 0; 1111 if (tick == NULL) { 1112 nd6_dad_ns_output(dp, ifa); 1113 nd6_dad_starttimer(dp, 1114 ND_IFINFO(ifa->ifa_ifp)->retrans * hz / 1000); 1115 } else { 1116 int ntick; 1117 1118 if (*tick == 0) 1119 ntick = krandom() % (MAX_RTR_SOLICITATION_DELAY * hz); 1120 else 1121 ntick = *tick + krandom() % (hz / 2); 1122 *tick = ntick; 1123 nd6_dad_starttimer(dp, ntick); 1124 } 1125 } 1126 1127 /* 1128 * terminate DAD unconditionally. used for address removals. 1129 */ 1130 void 1131 nd6_dad_stop(struct ifaddr *ifa) 1132 { 1133 struct dadq *dp; 1134 1135 if (!dad_init) 1136 return; 1137 dp = nd6_dad_find(ifa); 1138 if (!dp) { 1139 /* DAD wasn't started yet */ 1140 return; 1141 } 1142 1143 nd6_dad_stoptimer(dp); 1144 1145 TAILQ_REMOVE(&dadq, (struct dadq *)dp, dad_list); 1146 kfree(dp, M_IP6NDP); 1147 dp = NULL; 1148 crit_enter(); /* XXX MP not MP safe */ 1149 _IFAFREE(ifa, 0); 1150 crit_exit(); 1151 } 1152 1153 static void 1154 nd6_dad_timer(struct ifaddr *ifa) 1155 { 1156 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1157 struct dadq *dp; 1158 1159 crit_enter(); /* XXX */ 1160 1161 /* Sanity check */ 1162 if (ia == NULL) { 1163 log(LOG_ERR, "nd6_dad_timer: called with null parameter\n"); 1164 goto done; 1165 } 1166 dp = nd6_dad_find(ifa); 1167 if (dp == NULL) { 1168 log(LOG_ERR, "nd6_dad_timer: DAD structure not found\n"); 1169 goto done; 1170 } 1171 if (ia->ia6_flags & IN6_IFF_DUPLICATED) { 1172 log(LOG_ERR, "nd6_dad_timer: called with duplicated address " 1173 "%s(%s)\n", 1174 ip6_sprintf(&ia->ia_addr.sin6_addr), 1175 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1176 goto done; 1177 } 1178 if (!(ia->ia6_flags & IN6_IFF_TENTATIVE)) { 1179 log(LOG_ERR, "nd6_dad_timer: called with non-tentative address " 1180 "%s(%s)\n", 1181 ip6_sprintf(&ia->ia_addr.sin6_addr), 1182 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1183 goto done; 1184 } 1185 1186 /* timeouted with IFF_{RUNNING,UP} check */ 1187 if (dp->dad_ns_tcount > dad_maxtry) { 1188 nd6log((LOG_INFO, "%s: could not run DAD, driver problem?\n", 1189 if_name(ifa->ifa_ifp))); 1190 1191 TAILQ_REMOVE(&dadq, (struct dadq *)dp, dad_list); 1192 kfree(dp, M_IP6NDP); 1193 dp = NULL; 1194 crit_enter(); /* XXX MP not MP safe */ 1195 _IFAFREE(ifa, 0); 1196 crit_exit(); 1197 goto done; 1198 } 1199 1200 /* Need more checks? */ 1201 if (dp->dad_ns_ocount < dp->dad_count) { 1202 /* 1203 * We have more NS to go. Send NS packet for DAD. 1204 */ 1205 nd6_dad_ns_output(dp, ifa); 1206 nd6_dad_starttimer(dp, 1207 ND_IFINFO(ifa->ifa_ifp)->retrans * hz / 1000); 1208 } else { 1209 /* 1210 * We have transmitted sufficient number of DAD packets. 1211 * See what we've got. 1212 */ 1213 int duplicate; 1214 1215 duplicate = 0; 1216 1217 if (dp->dad_na_icount) { 1218 /* 1219 * the check is in nd6_dad_na_input(), 1220 * but just in case 1221 */ 1222 duplicate++; 1223 } 1224 1225 if (dp->dad_ns_icount) { 1226 #if 0 /* heuristics */ 1227 /* 1228 * if 1229 * - we have sent many(?) DAD NS, and 1230 * - the number of NS we sent equals to the 1231 * number of NS we've got, and 1232 * - we've got no NA 1233 * we may have a faulty network card/driver which 1234 * loops back multicasts to myself. 1235 */ 1236 if (3 < dp->dad_count 1237 && dp->dad_ns_icount == dp->dad_count 1238 && dp->dad_na_icount == 0) { 1239 log(LOG_INFO, "DAD questionable for %s(%s): " 1240 "network card loops back multicast?\n", 1241 ip6_sprintf(&ia->ia_addr.sin6_addr), 1242 if_name(ifa->ifa_ifp)); 1243 /* XXX consider it a duplicate or not? */ 1244 /* duplicate++; */ 1245 } else { 1246 /* We've seen NS, means DAD has failed. */ 1247 duplicate++; 1248 } 1249 #else 1250 /* We've seen NS, means DAD has failed. */ 1251 duplicate++; 1252 #endif 1253 } 1254 1255 if (duplicate) { 1256 /* (*dp) will be freed in nd6_dad_duplicated() */ 1257 dp = NULL; 1258 nd6_dad_duplicated(ifa); 1259 } else { 1260 /* 1261 * We are done with DAD. No NA came, no NS came. 1262 * duplicated address found. 1263 */ 1264 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1265 1266 nd6log((LOG_DEBUG, 1267 "%s: DAD complete for %s - no duplicates found\n", 1268 if_name(ifa->ifa_ifp), 1269 ip6_sprintf(&ia->ia_addr.sin6_addr))); 1270 1271 TAILQ_REMOVE(&dadq, (struct dadq *)dp, dad_list); 1272 kfree(dp, M_IP6NDP); 1273 dp = NULL; 1274 _IFAFREE(ifa, 0); 1275 } 1276 } 1277 1278 done: 1279 crit_exit(); 1280 } 1281 1282 void 1283 nd6_dad_duplicated(struct ifaddr *ifa) 1284 { 1285 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1286 struct dadq *dp; 1287 1288 dp = nd6_dad_find(ifa); 1289 if (dp == NULL) { 1290 log(LOG_ERR, "nd6_dad_duplicated: DAD structure not found\n"); 1291 return; 1292 } 1293 1294 log(LOG_ERR, "%s: DAD detected duplicate IPv6 address %s: " 1295 "NS in/out=%d/%d, NA in=%d\n", 1296 if_name(ifa->ifa_ifp), ip6_sprintf(&ia->ia_addr.sin6_addr), 1297 dp->dad_ns_icount, dp->dad_ns_ocount, dp->dad_na_icount); 1298 1299 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1300 ia->ia6_flags |= IN6_IFF_DUPLICATED; 1301 1302 /* We are done with DAD, with duplicated address found. (failure) */ 1303 nd6_dad_stoptimer(dp); 1304 1305 log(LOG_ERR, "%s: DAD complete for %s - duplicate found\n", 1306 if_name(ifa->ifa_ifp), ip6_sprintf(&ia->ia_addr.sin6_addr)); 1307 log(LOG_ERR, "%s: manual intervention required\n", 1308 if_name(ifa->ifa_ifp)); 1309 1310 TAILQ_REMOVE(&dadq, (struct dadq *)dp, dad_list); 1311 kfree(dp, M_IP6NDP); 1312 dp = NULL; 1313 crit_enter(); /* XXX MP not MP safe */ 1314 _IFAFREE(ifa, 0); 1315 crit_exit(); 1316 } 1317 1318 static void 1319 nd6_dad_ns_output(struct dadq *dp, struct ifaddr *ifa) 1320 { 1321 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1322 struct ifnet *ifp = ifa->ifa_ifp; 1323 1324 dp->dad_ns_tcount++; 1325 if (!(ifp->if_flags & IFF_UP)) { 1326 #if 0 1327 kprintf("%s: interface down?\n", if_name(ifp)); 1328 #endif 1329 return; 1330 } 1331 if (!(ifp->if_flags & IFF_RUNNING)) { 1332 #if 0 1333 kprintf("%s: interface not running?\n", if_name(ifp)); 1334 #endif 1335 return; 1336 } 1337 1338 dp->dad_ns_ocount++; 1339 nd6_ns_output(ifp, NULL, &ia->ia_addr.sin6_addr, NULL, 1); 1340 } 1341 1342 static void 1343 nd6_dad_ns_input(struct ifaddr *ifa) 1344 { 1345 struct in6_ifaddr *ia; 1346 struct ifnet *ifp; 1347 const struct in6_addr *taddr6; 1348 struct dadq *dp; 1349 int duplicate; 1350 1351 if (!ifa) 1352 panic("ifa == NULL in nd6_dad_ns_input"); 1353 1354 ia = (struct in6_ifaddr *)ifa; 1355 ifp = ifa->ifa_ifp; 1356 taddr6 = &ia->ia_addr.sin6_addr; 1357 duplicate = 0; 1358 dp = nd6_dad_find(ifa); 1359 1360 /* Quickhack - completely ignore DAD NS packets */ 1361 if (dad_ignore_ns) { 1362 nd6log((LOG_INFO, 1363 "nd6_dad_ns_input: ignoring DAD NS packet for " 1364 "address %s(%s)\n", ip6_sprintf(taddr6), 1365 if_name(ifa->ifa_ifp))); 1366 return; 1367 } 1368 1369 /* 1370 * if I'm yet to start DAD, someone else started using this address 1371 * first. I have a duplicate and you win. 1372 */ 1373 if (!dp || dp->dad_ns_ocount == 0) 1374 duplicate++; 1375 1376 /* XXX more checks for loopback situation - see nd6_dad_timer too */ 1377 1378 if (duplicate) { 1379 dp = NULL; /* will be freed in nd6_dad_duplicated() */ 1380 nd6_dad_duplicated(ifa); 1381 } else { 1382 /* 1383 * not sure if I got a duplicate. 1384 * increment ns count and see what happens. 1385 */ 1386 if (dp) 1387 dp->dad_ns_icount++; 1388 } 1389 } 1390 1391 static void 1392 nd6_dad_na_input(struct ifaddr *ifa) 1393 { 1394 struct dadq *dp; 1395 1396 if (!ifa) 1397 panic("ifa == NULL in nd6_dad_na_input"); 1398 1399 dp = nd6_dad_find(ifa); 1400 if (dp) 1401 dp->dad_na_icount++; 1402 1403 /* remove the address. */ 1404 nd6_dad_duplicated(ifa); 1405 } 1406