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sys/netinet6/nd6_nbr.c
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1 /*- 2 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project. 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. Neither the name of the project nor the names of its contributors 14 * may be used to endorse or promote products derived from this software 15 * without specific prior written permission. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE 21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * SUCH DAMAGE. 28 * 29 * $KAME: nd6_nbr.c,v 1.86 2002/01/21 02:33:04 jinmei Exp $ 30 */ 31 32 #include <sys/cdefs.h> 33 __FBSDID("$FreeBSD: releng/6.4/sys/netinet6/nd6_nbr.c 183529 2008-10-02 00:32:59Z cperciva $"); 34 35 #include "opt_inet.h" 36 #include "opt_inet6.h" 37 #include "opt_ipsec.h" 38 #include "opt_carp.h" 39 40 #include <sys/param.h> 41 #include <sys/systm.h> 42 #include <sys/malloc.h> 43 #include <sys/mbuf.h> 44 #include <sys/socket.h> 45 #include <sys/sockio.h> 46 #include <sys/time.h> 47 #include <sys/kernel.h> 48 #include <sys/errno.h> 49 #include <sys/syslog.h> 50 #include <sys/queue.h> 51 #include <sys/callout.h> 52 53 #include <net/if.h> 54 #include <net/if_types.h> 55 #include <net/if_dl.h> 56 #include <net/if_var.h> 57 #include <net/route.h> 58 59 #include <netinet/in.h> 60 #include <netinet/in_var.h> 61 #include <netinet6/in6_var.h> 62 #include <netinet6/in6_ifattach.h> 63 #include <netinet/ip6.h> 64 #include <netinet6/ip6_var.h> 65 #include <netinet6/scope6_var.h> 66 #include <netinet6/nd6.h> 67 #include <netinet/icmp6.h> 68 69 #ifdef DEV_CARP 70 #include <netinet/ip_carp.h> 71 #endif 72 73 #include <net/net_osdep.h> 74 75 #define SDL(s) ((struct sockaddr_dl *)s) 76 77 struct dadq; 78 static struct dadq *nd6_dad_find(struct ifaddr *); 79 static void nd6_dad_starttimer(struct dadq *, int); 80 static void nd6_dad_stoptimer(struct dadq *); 81 static void nd6_dad_timer(struct ifaddr *); 82 static void nd6_dad_ns_output(struct dadq *, struct ifaddr *); 83 static void nd6_dad_ns_input(struct ifaddr *); 84 static void nd6_dad_na_input(struct ifaddr *); 85 86 static int dad_ignore_ns = 0; /* ignore NS in DAD - specwise incorrect*/ 87 static int dad_maxtry = 15; /* max # of *tries* to transmit DAD packet */ 88 89 /* 90 * Input a Neighbor Solicitation Message. 91 * 92 * Based on RFC 2461 93 * Based on RFC 2462 (duplicate address detection) 94 */ 95 void 96 nd6_ns_input(m, off, icmp6len) 97 struct mbuf *m; 98 int off, icmp6len; 99 { 100 struct ifnet *ifp = m->m_pkthdr.rcvif; 101 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 102 struct nd_neighbor_solicit *nd_ns; 103 struct in6_addr saddr6 = ip6->ip6_src; 104 struct in6_addr daddr6 = ip6->ip6_dst; 105 struct in6_addr taddr6; 106 struct in6_addr myaddr6; 107 char *lladdr = NULL; 108 struct ifaddr *ifa = NULL; 109 int lladdrlen = 0; 110 int anycast = 0, proxy = 0, tentative = 0; 111 int tlladdr; 112 union nd_opts ndopts; 113 struct sockaddr_dl *proxydl = NULL; 114 115 #ifndef PULLDOWN_TEST 116 IP6_EXTHDR_CHECK(m, off, icmp6len,); 117 nd_ns = (struct nd_neighbor_solicit *)((caddr_t)ip6 + off); 118 #else 119 IP6_EXTHDR_GET(nd_ns, struct nd_neighbor_solicit *, m, off, icmp6len); 120 if (nd_ns == NULL) { 121 icmp6stat.icp6s_tooshort++; 122 return; 123 } 124 #endif 125 ip6 = mtod(m, struct ip6_hdr *); /* adjust pointer for safety */ 126 taddr6 = nd_ns->nd_ns_target; 127 if (in6_setscope(&taddr6, ifp, NULL) != 0) 128 goto bad; 129 130 if (ip6->ip6_hlim != 255) { 131 nd6log((LOG_ERR, 132 "nd6_ns_input: invalid hlim (%d) from %s to %s on %s\n", 133 ip6->ip6_hlim, ip6_sprintf(&ip6->ip6_src), 134 ip6_sprintf(&ip6->ip6_dst), if_name(ifp))); 135 goto bad; 136 } 137 138 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) { 139 /* dst has to be a solicited node multicast address. */ 140 if (daddr6.s6_addr16[0] == IPV6_ADDR_INT16_MLL && 141 /* don't check ifindex portion */ 142 daddr6.s6_addr32[1] == 0 && 143 daddr6.s6_addr32[2] == IPV6_ADDR_INT32_ONE && 144 daddr6.s6_addr8[12] == 0xff) { 145 ; /* good */ 146 } else { 147 nd6log((LOG_INFO, "nd6_ns_input: bad DAD packet " 148 "(wrong ip6 dst)\n")); 149 goto bad; 150 } 151 } else if (!nd6_onlink_ns_rfc4861) { 152 struct sockaddr_in6 src_sa6; 153 154 /* 155 * According to recent IETF discussions, it is not a good idea 156 * to accept a NS from an address which would not be deemed 157 * to be a neighbor otherwise. This point is expected to be 158 * clarified in future revisions of the specification. 159 */ 160 bzero(&src_sa6, sizeof(src_sa6)); 161 src_sa6.sin6_family = AF_INET6; 162 src_sa6.sin6_len = sizeof(src_sa6); 163 src_sa6.sin6_addr = saddr6; 164 if (!nd6_is_addr_neighbor(&src_sa6, ifp)) { 165 nd6log((LOG_INFO, "nd6_ns_input: " 166 "NS packet from non-neighbor\n")); 167 goto bad; 168 } 169 } 170 171 if (IN6_IS_ADDR_MULTICAST(&taddr6)) { 172 nd6log((LOG_INFO, "nd6_ns_input: bad NS target (multicast)\n")); 173 goto bad; 174 } 175 176 icmp6len -= sizeof(*nd_ns); 177 nd6_option_init(nd_ns + 1, icmp6len, &ndopts); 178 if (nd6_options(&ndopts) < 0) { 179 nd6log((LOG_INFO, 180 "nd6_ns_input: invalid ND option, ignored\n")); 181 /* nd6_options have incremented stats */ 182 goto freeit; 183 } 184 185 if (ndopts.nd_opts_src_lladdr) { 186 lladdr = (char *)(ndopts.nd_opts_src_lladdr + 1); 187 lladdrlen = ndopts.nd_opts_src_lladdr->nd_opt_len << 3; 188 } 189 190 if (IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_src) && lladdr) { 191 nd6log((LOG_INFO, "nd6_ns_input: bad DAD packet " 192 "(link-layer address option)\n")); 193 goto bad; 194 } 195 196 /* 197 * Attaching target link-layer address to the NA? 198 * (RFC 2461 7.2.4) 199 * 200 * NS IP dst is unicast/anycast MUST NOT add 201 * NS IP dst is solicited-node multicast MUST add 202 * 203 * In implementation, we add target link-layer address by default. 204 * We do not add one in MUST NOT cases. 205 */ 206 if (!IN6_IS_ADDR_MULTICAST(&daddr6)) 207 tlladdr = 0; 208 else 209 tlladdr = 1; 210 211 /* 212 * Target address (taddr6) must be either: 213 * (1) Valid unicast/anycast address for my receiving interface, 214 * (2) Unicast address for which I'm offering proxy service, or 215 * (3) "tentative" address on which DAD is being performed. 216 */ 217 /* (1) and (3) check. */ 218 #ifdef DEV_CARP 219 if (ifp->if_carp) 220 ifa = carp_iamatch6(ifp->if_carp, &taddr6); 221 if (ifa == NULL) 222 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &taddr6); 223 #else 224 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &taddr6); 225 #endif 226 227 /* (2) check. */ 228 if (ifa == NULL) { 229 struct rtentry *rt; 230 struct sockaddr_in6 tsin6; 231 int need_proxy; 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 = rtalloc1((struct sockaddr *)&tsin6, 0, 0); 239 need_proxy = (rt && (rt->rt_flags & RTF_ANNOUNCE) != 0 && 240 rt->rt_gateway->sa_family == AF_LINK); 241 if (rt) 242 rtfree(rt); 243 if (need_proxy) { 244 /* 245 * proxy NDP for single entry 246 */ 247 ifa = (struct ifaddr *)in6ifa_ifpforlinklocal(ifp, 248 IN6_IFF_NOTREADY|IN6_IFF_ANYCAST); 249 if (ifa) { 250 proxy = 1; 251 proxydl = SDL(rt->rt_gateway); 252 } 253 } 254 } 255 if (ifa == NULL) { 256 /* 257 * We've got an NS packet, and we don't have that adddress 258 * assigned for us. We MUST silently ignore it. 259 * See RFC2461 7.2.3. 260 */ 261 goto freeit; 262 } 263 myaddr6 = *IFA_IN6(ifa); 264 anycast = ((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_ANYCAST; 265 tentative = ((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_TENTATIVE; 266 if (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_DUPLICATED) 267 goto freeit; 268 269 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) { 270 nd6log((LOG_INFO, "nd6_ns_input: lladdrlen mismatch for %s " 271 "(if %d, NS packet %d)\n", 272 ip6_sprintf(&taddr6), 273 ifp->if_addrlen, lladdrlen - 2)); 274 goto bad; 275 } 276 277 if (IN6_ARE_ADDR_EQUAL(&myaddr6, &saddr6)) { 278 nd6log((LOG_INFO, "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 * duplicate 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 struct in6_addr in6_all; 319 320 in6_all = in6addr_linklocal_allnodes; 321 if (in6_setscope(&in6_all, ifp, NULL) != 0) 322 goto bad; 323 nd6_na_output(ifp, &in6_all, &taddr6, 324 ((anycast || proxy || !tlladdr) ? 0 : ND_NA_FLAG_OVERRIDE) | 325 (ip6_forwarding ? ND_NA_FLAG_ROUTER : 0), 326 tlladdr, (struct sockaddr *)proxydl); 327 goto freeit; 328 } 329 330 nd6_cache_lladdr(ifp, &saddr6, lladdr, lladdrlen, 331 ND_NEIGHBOR_SOLICIT, 0); 332 333 nd6_na_output(ifp, &saddr6, &taddr6, 334 ((anycast || proxy || !tlladdr) ? 0 : ND_NA_FLAG_OVERRIDE) | 335 (ip6_forwarding ? ND_NA_FLAG_ROUTER : 0) | ND_NA_FLAG_SOLICITED, 336 tlladdr, (struct sockaddr *)proxydl); 337 freeit: 338 m_freem(m); 339 return; 340 341 bad: 342 nd6log((LOG_ERR, "nd6_ns_input: src=%s\n", ip6_sprintf(&saddr6))); 343 nd6log((LOG_ERR, "nd6_ns_input: dst=%s\n", ip6_sprintf(&daddr6))); 344 nd6log((LOG_ERR, "nd6_ns_input: tgt=%s\n", ip6_sprintf(&taddr6))); 345 icmp6stat.icp6s_badns++; 346 m_freem(m); 347 } 348 349 /* 350 * Output a Neighbor Solicitation Message. Caller specifies: 351 * - ICMP6 header source IP6 address 352 * - ND6 header target IP6 address 353 * - ND6 header source datalink address 354 * 355 * Based on RFC 2461 356 * Based on RFC 2462 (duplicate address detection) 357 */ 358 void 359 nd6_ns_output(ifp, daddr6, taddr6, ln, dad) 360 struct ifnet *ifp; 361 const struct in6_addr *daddr6, *taddr6; 362 struct llinfo_nd6 *ln; /* for source address determination */ 363 int dad; /* duplicate address detection */ 364 { 365 struct mbuf *m; 366 struct ip6_hdr *ip6; 367 struct nd_neighbor_solicit *nd_ns; 368 struct in6_addr *src, src_in; 369 struct ip6_moptions im6o; 370 int icmp6len; 371 int maxlen; 372 caddr_t mac; 373 struct route_in6 ro; 374 375 bzero(&ro, sizeof(ro)); 376 377 if (IN6_IS_ADDR_MULTICAST(taddr6)) 378 return; 379 380 /* estimate the size of message */ 381 maxlen = sizeof(*ip6) + sizeof(*nd_ns); 382 maxlen += (sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7; 383 if (max_linkhdr + maxlen >= MCLBYTES) { 384 #ifdef DIAGNOSTIC 385 printf("nd6_ns_output: max_linkhdr + maxlen >= MCLBYTES " 386 "(%d + %d > %d)\n", max_linkhdr, maxlen, MCLBYTES); 387 #endif 388 return; 389 } 390 391 MGETHDR(m, M_DONTWAIT, MT_DATA); 392 if (m && max_linkhdr + maxlen >= MHLEN) { 393 MCLGET(m, M_DONTWAIT); 394 if ((m->m_flags & M_EXT) == 0) { 395 m_free(m); 396 m = NULL; 397 } 398 } 399 if (m == NULL) 400 return; 401 m->m_pkthdr.rcvif = NULL; 402 403 if (daddr6 == NULL || IN6_IS_ADDR_MULTICAST(daddr6)) { 404 m->m_flags |= M_MCAST; 405 im6o.im6o_multicast_ifp = ifp; 406 im6o.im6o_multicast_hlim = 255; 407 im6o.im6o_multicast_loop = 0; 408 } 409 410 icmp6len = sizeof(*nd_ns); 411 m->m_pkthdr.len = m->m_len = sizeof(*ip6) + icmp6len; 412 m->m_data += max_linkhdr; /* or MH_ALIGN() equivalent? */ 413 414 /* fill neighbor solicitation packet */ 415 ip6 = mtod(m, struct ip6_hdr *); 416 ip6->ip6_flow = 0; 417 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 418 ip6->ip6_vfc |= IPV6_VERSION; 419 /* ip6->ip6_plen will be set later */ 420 ip6->ip6_nxt = IPPROTO_ICMPV6; 421 ip6->ip6_hlim = 255; 422 if (daddr6) 423 ip6->ip6_dst = *daddr6; 424 else { 425 ip6->ip6_dst.s6_addr16[0] = IPV6_ADDR_INT16_MLL; 426 ip6->ip6_dst.s6_addr16[1] = 0; 427 ip6->ip6_dst.s6_addr32[1] = 0; 428 ip6->ip6_dst.s6_addr32[2] = IPV6_ADDR_INT32_ONE; 429 ip6->ip6_dst.s6_addr32[3] = taddr6->s6_addr32[3]; 430 ip6->ip6_dst.s6_addr8[12] = 0xff; 431 if (in6_setscope(&ip6->ip6_dst, ifp, NULL) != 0) 432 goto bad; 433 } 434 if (!dad) { 435 /* 436 * RFC2461 7.2.2: 437 * "If the source address of the packet prompting the 438 * solicitation is the same as one of the addresses assigned 439 * to the outgoing interface, that address SHOULD be placed 440 * in the IP Source Address of the outgoing solicitation. 441 * Otherwise, any one of the addresses assigned to the 442 * interface should be used." 443 * 444 * We use the source address for the prompting packet 445 * (saddr6), if: 446 * - saddr6 is given from the caller (by giving "ln"), and 447 * - saddr6 belongs to the outgoing interface. 448 * Otherwise, we perform the source address selection as usual. 449 */ 450 struct ip6_hdr *hip6; /* hold ip6 */ 451 struct in6_addr *hsrc = NULL; 452 453 if (ln && ln->ln_hold) { 454 /* 455 * assuming every packet in ln_hold has the same IP 456 * header 457 */ 458 hip6 = mtod(ln->ln_hold, struct ip6_hdr *); 459 /* XXX pullup? */ 460 if (sizeof(*hip6) < ln->ln_hold->m_len) 461 hsrc = &hip6->ip6_src; 462 else 463 hsrc = NULL; 464 } 465 if (hsrc && in6ifa_ifpwithaddr(ifp, hsrc)) 466 src = hsrc; 467 else { 468 int error; 469 struct sockaddr_in6 dst_sa; 470 471 bzero(&dst_sa, sizeof(dst_sa)); 472 dst_sa.sin6_family = AF_INET6; 473 dst_sa.sin6_len = sizeof(dst_sa); 474 dst_sa.sin6_addr = ip6->ip6_dst; 475 476 src = in6_selectsrc(&dst_sa, NULL, 477 NULL, &ro, NULL, NULL, &error); 478 if (src == NULL) { 479 nd6log((LOG_DEBUG, 480 "nd6_ns_output: source can't be " 481 "determined: dst=%s, error=%d\n", 482 ip6_sprintf(&dst_sa.sin6_addr), error)); 483 goto bad; 484 } 485 } 486 } else { 487 /* 488 * Source address for DAD packet must always be IPv6 489 * unspecified address. (0::0) 490 * We actually don't have to 0-clear the address (we did it 491 * above), but we do so here explicitly to make the intention 492 * clearer. 493 */ 494 bzero(&src_in, sizeof(src_in)); 495 src = &src_in; 496 } 497 ip6->ip6_src = *src; 498 nd_ns = (struct nd_neighbor_solicit *)(ip6 + 1); 499 nd_ns->nd_ns_type = ND_NEIGHBOR_SOLICIT; 500 nd_ns->nd_ns_code = 0; 501 nd_ns->nd_ns_reserved = 0; 502 nd_ns->nd_ns_target = *taddr6; 503 in6_clearscope(&nd_ns->nd_ns_target); /* XXX */ 504 505 /* 506 * Add source link-layer address option. 507 * 508 * spec implementation 509 * --- --- 510 * DAD packet MUST NOT do not add the option 511 * there's no link layer address: 512 * impossible do not add the option 513 * there's link layer address: 514 * Multicast NS MUST add one add the option 515 * Unicast NS SHOULD add one add the option 516 */ 517 if (!dad && (mac = nd6_ifptomac(ifp))) { 518 int optlen = sizeof(struct nd_opt_hdr) + ifp->if_addrlen; 519 struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)(nd_ns + 1); 520 /* 8 byte alignments... */ 521 optlen = (optlen + 7) & ~7; 522 523 m->m_pkthdr.len += optlen; 524 m->m_len += optlen; 525 icmp6len += optlen; 526 bzero((caddr_t)nd_opt, optlen); 527 nd_opt->nd_opt_type = ND_OPT_SOURCE_LINKADDR; 528 nd_opt->nd_opt_len = optlen >> 3; 529 bcopy(mac, (caddr_t)(nd_opt + 1), ifp->if_addrlen); 530 } 531 532 ip6->ip6_plen = htons((u_short)icmp6len); 533 nd_ns->nd_ns_cksum = 0; 534 nd_ns->nd_ns_cksum = 535 in6_cksum(m, IPPROTO_ICMPV6, sizeof(*ip6), icmp6len); 536 537 ip6_output(m, NULL, &ro, dad ? IPV6_UNSPECSRC : 0, &im6o, NULL, NULL); 538 icmp6_ifstat_inc(ifp, ifs6_out_msg); 539 icmp6_ifstat_inc(ifp, ifs6_out_neighborsolicit); 540 icmp6stat.icp6s_outhist[ND_NEIGHBOR_SOLICIT]++; 541 542 if (ro.ro_rt) { /* we don't cache this route. */ 543 RTFREE(ro.ro_rt); 544 } 545 return; 546 547 bad: 548 if (ro.ro_rt) { 549 RTFREE(ro.ro_rt); 550 } 551 m_freem(m); 552 return; 553 } 554 555 /* 556 * Neighbor advertisement input handling. 557 * 558 * Based on RFC 2461 559 * Based on RFC 2462 (duplicate address detection) 560 * 561 * the following items are not implemented yet: 562 * - proxy advertisement delay rule (RFC2461 7.2.8, last paragraph, SHOULD) 563 * - anycast advertisement delay rule (RFC2461 7.2.7, SHOULD) 564 */ 565 void 566 nd6_na_input(m, off, icmp6len) 567 struct mbuf *m; 568 int off, icmp6len; 569 { 570 struct ifnet *ifp = m->m_pkthdr.rcvif; 571 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 572 struct nd_neighbor_advert *nd_na; 573 struct in6_addr daddr6 = ip6->ip6_dst; 574 struct in6_addr taddr6; 575 int flags; 576 int is_router; 577 int is_solicited; 578 int is_override; 579 char *lladdr = NULL; 580 int lladdrlen = 0; 581 struct ifaddr *ifa; 582 struct llinfo_nd6 *ln; 583 struct rtentry *rt; 584 struct sockaddr_dl *sdl; 585 union nd_opts ndopts; 586 587 if (ip6->ip6_hlim != 255) { 588 nd6log((LOG_ERR, 589 "nd6_na_input: invalid hlim (%d) from %s to %s on %s\n", 590 ip6->ip6_hlim, ip6_sprintf(&ip6->ip6_src), 591 ip6_sprintf(&ip6->ip6_dst), if_name(ifp))); 592 goto bad; 593 } 594 595 #ifndef PULLDOWN_TEST 596 IP6_EXTHDR_CHECK(m, off, icmp6len,); 597 nd_na = (struct nd_neighbor_advert *)((caddr_t)ip6 + off); 598 #else 599 IP6_EXTHDR_GET(nd_na, struct nd_neighbor_advert *, m, off, icmp6len); 600 if (nd_na == NULL) { 601 icmp6stat.icp6s_tooshort++; 602 return; 603 } 604 #endif 605 606 flags = nd_na->nd_na_flags_reserved; 607 is_router = ((flags & ND_NA_FLAG_ROUTER) != 0); 608 is_solicited = ((flags & ND_NA_FLAG_SOLICITED) != 0); 609 is_override = ((flags & ND_NA_FLAG_OVERRIDE) != 0); 610 611 taddr6 = nd_na->nd_na_target; 612 if (in6_setscope(&taddr6, ifp, NULL)) 613 goto bad; /* XXX: impossible */ 614 615 if (IN6_IS_ADDR_MULTICAST(&taddr6)) { 616 nd6log((LOG_ERR, 617 "nd6_na_input: invalid target address %s\n", 618 ip6_sprintf(&taddr6))); 619 goto bad; 620 } 621 if (IN6_IS_ADDR_MULTICAST(&daddr6)) 622 if (is_solicited) { 623 nd6log((LOG_ERR, 624 "nd6_na_input: a solicited adv is multicasted\n")); 625 goto bad; 626 } 627 628 icmp6len -= sizeof(*nd_na); 629 nd6_option_init(nd_na + 1, icmp6len, &ndopts); 630 if (nd6_options(&ndopts) < 0) { 631 nd6log((LOG_INFO, 632 "nd6_na_input: invalid ND option, ignored\n")); 633 /* nd6_options have incremented stats */ 634 goto freeit; 635 } 636 637 if (ndopts.nd_opts_tgt_lladdr) { 638 lladdr = (char *)(ndopts.nd_opts_tgt_lladdr + 1); 639 lladdrlen = ndopts.nd_opts_tgt_lladdr->nd_opt_len << 3; 640 } 641 642 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &taddr6); 643 644 /* 645 * Target address matches one of my interface address. 646 * 647 * If my address is tentative, this means that there's somebody 648 * already using the same address as mine. This indicates DAD failure. 649 * This is defined in RFC 2462. 650 * 651 * Otherwise, process as defined in RFC 2461. 652 */ 653 if (ifa 654 && (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_TENTATIVE)) { 655 nd6_dad_na_input(ifa); 656 goto freeit; 657 } 658 659 /* Just for safety, maybe unnecessary. */ 660 if (ifa) { 661 log(LOG_ERR, 662 "nd6_na_input: duplicate IP6 address %s\n", 663 ip6_sprintf(&taddr6)); 664 goto freeit; 665 } 666 667 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) { 668 nd6log((LOG_INFO, "nd6_na_input: lladdrlen mismatch for %s " 669 "(if %d, NA packet %d)\n", ip6_sprintf(&taddr6), 670 ifp->if_addrlen, lladdrlen - 2)); 671 goto bad; 672 } 673 674 /* 675 * If no neighbor cache entry is found, NA SHOULD silently be 676 * discarded. 677 */ 678 rt = nd6_lookup(&taddr6, 0, ifp); 679 if ((rt == NULL) || 680 ((ln = (struct llinfo_nd6 *)rt->rt_llinfo) == NULL) || 681 ((sdl = SDL(rt->rt_gateway)) == NULL)) 682 goto freeit; 683 684 if (ln->ln_state == ND6_LLINFO_INCOMPLETE) { 685 /* 686 * If the link-layer has address, and no lladdr option came, 687 * discard the packet. 688 */ 689 if (ifp->if_addrlen && lladdr == NULL) 690 goto freeit; 691 692 /* 693 * Record link-layer address, and update the state. 694 */ 695 sdl->sdl_alen = ifp->if_addrlen; 696 bcopy(lladdr, LLADDR(sdl), ifp->if_addrlen); 697 if (is_solicited) { 698 ln->ln_state = ND6_LLINFO_REACHABLE; 699 ln->ln_byhint = 0; 700 if (!ND6_LLINFO_PERMANENT(ln)) { 701 nd6_llinfo_settimer(ln, 702 (long)ND_IFINFO(rt->rt_ifp)->reachable * hz); 703 } 704 } else { 705 ln->ln_state = ND6_LLINFO_STALE; 706 nd6_llinfo_settimer(ln, (long)nd6_gctimer * hz); 707 } 708 if ((ln->ln_router = is_router) != 0) { 709 /* 710 * This means a router's state has changed from 711 * non-reachable to probably reachable, and might 712 * affect the status of associated prefixes.. 713 */ 714 pfxlist_onlink_check(); 715 } 716 } else { 717 int llchange; 718 719 /* 720 * Check if the link-layer address has changed or not. 721 */ 722 if (lladdr == NULL) 723 llchange = 0; 724 else { 725 if (sdl->sdl_alen) { 726 if (bcmp(lladdr, LLADDR(sdl), ifp->if_addrlen)) 727 llchange = 1; 728 else 729 llchange = 0; 730 } else 731 llchange = 1; 732 } 733 734 /* 735 * This is VERY complex. Look at it with care. 736 * 737 * override solicit lladdr llchange action 738 * (L: record lladdr) 739 * 740 * 0 0 n -- (2c) 741 * 0 0 y n (2b) L 742 * 0 0 y y (1) REACHABLE->STALE 743 * 0 1 n -- (2c) *->REACHABLE 744 * 0 1 y n (2b) L *->REACHABLE 745 * 0 1 y y (1) REACHABLE->STALE 746 * 1 0 n -- (2a) 747 * 1 0 y n (2a) L 748 * 1 0 y y (2a) L *->STALE 749 * 1 1 n -- (2a) *->REACHABLE 750 * 1 1 y n (2a) L *->REACHABLE 751 * 1 1 y y (2a) L *->REACHABLE 752 */ 753 if (!is_override && (lladdr != NULL && llchange)) { /* (1) */ 754 /* 755 * If state is REACHABLE, make it STALE. 756 * no other updates should be done. 757 */ 758 if (ln->ln_state == ND6_LLINFO_REACHABLE) { 759 ln->ln_state = ND6_LLINFO_STALE; 760 nd6_llinfo_settimer(ln, (long)nd6_gctimer * hz); 761 } 762 goto freeit; 763 } else if (is_override /* (2a) */ 764 || (!is_override && (lladdr != NULL && !llchange)) /* (2b) */ 765 || lladdr == NULL) { /* (2c) */ 766 /* 767 * Update link-local address, if any. 768 */ 769 if (lladdr != NULL) { 770 sdl->sdl_alen = ifp->if_addrlen; 771 bcopy(lladdr, LLADDR(sdl), ifp->if_addrlen); 772 } 773 774 /* 775 * If solicited, make the state REACHABLE. 776 * If not solicited and the link-layer address was 777 * changed, make it STALE. 778 */ 779 if (is_solicited) { 780 ln->ln_state = ND6_LLINFO_REACHABLE; 781 ln->ln_byhint = 0; 782 if (!ND6_LLINFO_PERMANENT(ln)) { 783 nd6_llinfo_settimer(ln, 784 (long)ND_IFINFO(ifp)->reachable * hz); 785 } 786 } else { 787 if (lladdr != NULL && llchange) { 788 ln->ln_state = ND6_LLINFO_STALE; 789 nd6_llinfo_settimer(ln, 790 (long)nd6_gctimer * hz); 791 } 792 } 793 } 794 795 if (ln->ln_router && !is_router) { 796 /* 797 * The peer dropped the router flag. 798 * Remove the sender from the Default Router List and 799 * update the Destination Cache entries. 800 */ 801 struct nd_defrouter *dr; 802 struct in6_addr *in6; 803 int s; 804 805 in6 = &((struct sockaddr_in6 *)rt_key(rt))->sin6_addr; 806 807 /* 808 * Lock to protect the default router list. 809 * XXX: this might be unnecessary, since this function 810 * is only called under the network software interrupt 811 * context. However, we keep it just for safety. 812 */ 813 s = splnet(); 814 dr = defrouter_lookup(in6, ifp); 815 if (dr) 816 defrtrlist_del(dr); 817 else if (!ip6_forwarding) { 818 /* 819 * Even if the neighbor is not in the default 820 * router list, the neighbor may be used 821 * as a next hop for some destinations 822 * (e.g. redirect case). So we must 823 * call rt6_flush explicitly. 824 */ 825 rt6_flush(&ip6->ip6_src, ifp); 826 } 827 splx(s); 828 } 829 ln->ln_router = is_router; 830 } 831 rt->rt_flags &= ~RTF_REJECT; 832 ln->ln_asked = 0; 833 if (ln->ln_hold) { 834 struct mbuf *m_hold, *m_hold_next; 835 836 /* 837 * reset the ln_hold in advance, to explicitly 838 * prevent a ln_hold lookup in nd6_output() 839 * (wouldn't happen, though...) 840 */ 841 for (m_hold = ln->ln_hold, ln->ln_hold = NULL; 842 m_hold; m_hold = m_hold_next) { 843 m_hold_next = m_hold->m_nextpkt; 844 m_hold->m_nextpkt = NULL; 845 /* 846 * we assume ifp is not a loopback here, so just set 847 * the 2nd argument as the 1st one. 848 */ 849 nd6_output(ifp, ifp, m_hold, 850 (struct sockaddr_in6 *)rt_key(rt), rt); 851 } 852 } 853 854 freeit: 855 m_freem(m); 856 return; 857 858 bad: 859 icmp6stat.icp6s_badna++; 860 m_freem(m); 861 } 862 863 /* 864 * Neighbor advertisement output handling. 865 * 866 * Based on RFC 2461 867 * 868 * the following items are not implemented yet: 869 * - proxy advertisement delay rule (RFC2461 7.2.8, last paragraph, SHOULD) 870 * - anycast advertisement delay rule (RFC2461 7.2.7, SHOULD) 871 */ 872 void 873 nd6_na_output(ifp, daddr6_0, taddr6, flags, tlladdr, sdl0) 874 struct ifnet *ifp; 875 const struct in6_addr *daddr6_0, *taddr6; 876 u_long flags; 877 int tlladdr; /* 1 if include target link-layer address */ 878 struct sockaddr *sdl0; /* sockaddr_dl (= proxy NA) or NULL */ 879 { 880 struct mbuf *m; 881 struct ip6_hdr *ip6; 882 struct nd_neighbor_advert *nd_na; 883 struct ip6_moptions im6o; 884 struct in6_addr *src, daddr6; 885 struct sockaddr_in6 dst_sa; 886 int icmp6len, maxlen, error; 887 caddr_t mac = NULL; 888 struct route_in6 ro; 889 890 bzero(&ro, sizeof(ro)); 891 892 daddr6 = *daddr6_0; /* make a local copy for modification */ 893 894 /* estimate the size of message */ 895 maxlen = sizeof(*ip6) + sizeof(*nd_na); 896 maxlen += (sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7; 897 if (max_linkhdr + maxlen >= MCLBYTES) { 898 #ifdef DIAGNOSTIC 899 printf("nd6_na_output: max_linkhdr + maxlen >= MCLBYTES " 900 "(%d + %d > %d)\n", max_linkhdr, maxlen, MCLBYTES); 901 #endif 902 return; 903 } 904 905 MGETHDR(m, M_DONTWAIT, MT_DATA); 906 if (m && max_linkhdr + maxlen >= MHLEN) { 907 MCLGET(m, M_DONTWAIT); 908 if ((m->m_flags & M_EXT) == 0) { 909 m_free(m); 910 m = NULL; 911 } 912 } 913 if (m == NULL) 914 return; 915 m->m_pkthdr.rcvif = NULL; 916 917 if (IN6_IS_ADDR_MULTICAST(&daddr6)) { 918 m->m_flags |= M_MCAST; 919 im6o.im6o_multicast_ifp = ifp; 920 im6o.im6o_multicast_hlim = 255; 921 im6o.im6o_multicast_loop = 0; 922 } 923 924 icmp6len = sizeof(*nd_na); 925 m->m_pkthdr.len = m->m_len = sizeof(struct ip6_hdr) + icmp6len; 926 m->m_data += max_linkhdr; /* or MH_ALIGN() equivalent? */ 927 928 /* fill neighbor advertisement packet */ 929 ip6 = mtod(m, struct ip6_hdr *); 930 ip6->ip6_flow = 0; 931 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 932 ip6->ip6_vfc |= IPV6_VERSION; 933 ip6->ip6_nxt = IPPROTO_ICMPV6; 934 ip6->ip6_hlim = 255; 935 if (IN6_IS_ADDR_UNSPECIFIED(&daddr6)) { 936 /* reply to DAD */ 937 daddr6.s6_addr16[0] = IPV6_ADDR_INT16_MLL; 938 daddr6.s6_addr16[1] = 0; 939 daddr6.s6_addr32[1] = 0; 940 daddr6.s6_addr32[2] = 0; 941 daddr6.s6_addr32[3] = IPV6_ADDR_INT32_ONE; 942 if (in6_setscope(&daddr6, ifp, NULL)) 943 goto bad; 944 945 flags &= ~ND_NA_FLAG_SOLICITED; 946 } 947 ip6->ip6_dst = daddr6; 948 bzero(&dst_sa, sizeof(struct sockaddr_in6)); 949 dst_sa.sin6_family = AF_INET6; 950 dst_sa.sin6_len = sizeof(struct sockaddr_in6); 951 dst_sa.sin6_addr = daddr6; 952 953 /* 954 * Select a source whose scope is the same as that of the dest. 955 */ 956 bcopy(&dst_sa, &ro.ro_dst, sizeof(dst_sa)); 957 src = in6_selectsrc(&dst_sa, NULL, NULL, &ro, NULL, NULL, &error); 958 if (src == NULL) { 959 nd6log((LOG_DEBUG, "nd6_na_output: source can't be " 960 "determined: dst=%s, error=%d\n", 961 ip6_sprintf(&dst_sa.sin6_addr), error)); 962 goto bad; 963 } 964 ip6->ip6_src = *src; 965 nd_na = (struct nd_neighbor_advert *)(ip6 + 1); 966 nd_na->nd_na_type = ND_NEIGHBOR_ADVERT; 967 nd_na->nd_na_code = 0; 968 nd_na->nd_na_target = *taddr6; 969 in6_clearscope(&nd_na->nd_na_target); /* XXX */ 970 971 /* 972 * "tlladdr" indicates NS's condition for adding tlladdr or not. 973 * see nd6_ns_input() for details. 974 * Basically, if NS packet is sent to unicast/anycast addr, 975 * target lladdr option SHOULD NOT be included. 976 */ 977 if (tlladdr) { 978 /* 979 * sdl0 != NULL indicates proxy NA. If we do proxy, use 980 * lladdr in sdl0. If we are not proxying (sending NA for 981 * my address) use lladdr configured for the interface. 982 */ 983 if (sdl0 == NULL) { 984 #ifdef DEV_CARP 985 if (ifp->if_carp) 986 mac = carp_macmatch6(ifp->if_carp, m, taddr6); 987 if (mac == NULL) 988 mac = nd6_ifptomac(ifp); 989 #else 990 mac = nd6_ifptomac(ifp); 991 #endif 992 } else if (sdl0->sa_family == AF_LINK) { 993 struct sockaddr_dl *sdl; 994 sdl = (struct sockaddr_dl *)sdl0; 995 if (sdl->sdl_alen == ifp->if_addrlen) 996 mac = LLADDR(sdl); 997 } 998 } 999 if (tlladdr && mac) { 1000 int optlen = sizeof(struct nd_opt_hdr) + ifp->if_addrlen; 1001 struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)(nd_na + 1); 1002 1003 /* roundup to 8 bytes alignment! */ 1004 optlen = (optlen + 7) & ~7; 1005 1006 m->m_pkthdr.len += optlen; 1007 m->m_len += optlen; 1008 icmp6len += optlen; 1009 bzero((caddr_t)nd_opt, optlen); 1010 nd_opt->nd_opt_type = ND_OPT_TARGET_LINKADDR; 1011 nd_opt->nd_opt_len = optlen >> 3; 1012 bcopy(mac, (caddr_t)(nd_opt + 1), ifp->if_addrlen); 1013 } else 1014 flags &= ~ND_NA_FLAG_OVERRIDE; 1015 1016 ip6->ip6_plen = htons((u_short)icmp6len); 1017 nd_na->nd_na_flags_reserved = flags; 1018 nd_na->nd_na_cksum = 0; 1019 nd_na->nd_na_cksum = 1020 in6_cksum(m, IPPROTO_ICMPV6, sizeof(struct ip6_hdr), icmp6len); 1021 1022 ip6_output(m, NULL, &ro, 0, &im6o, NULL, NULL); 1023 icmp6_ifstat_inc(ifp, ifs6_out_msg); 1024 icmp6_ifstat_inc(ifp, ifs6_out_neighboradvert); 1025 icmp6stat.icp6s_outhist[ND_NEIGHBOR_ADVERT]++; 1026 1027 if (ro.ro_rt) { /* we don't cache this route. */ 1028 RTFREE(ro.ro_rt); 1029 } 1030 return; 1031 1032 bad: 1033 if (ro.ro_rt) { 1034 RTFREE(ro.ro_rt); 1035 } 1036 m_freem(m); 1037 return; 1038 } 1039 1040 caddr_t 1041 nd6_ifptomac(ifp) 1042 struct ifnet *ifp; 1043 { 1044 switch (ifp->if_type) { 1045 case IFT_ARCNET: 1046 case IFT_ETHER: 1047 case IFT_FDDI: 1048 case IFT_IEEE1394: 1049 #ifdef IFT_L2VLAN 1050 case IFT_L2VLAN: 1051 #endif 1052 #ifdef IFT_IEEE80211 1053 case IFT_IEEE80211: 1054 #endif 1055 #ifdef IFT_CARP 1056 case IFT_CARP: 1057 #endif 1058 case IFT_BRIDGE: 1059 case IFT_ISO88025: 1060 return IF_LLADDR(ifp); 1061 default: 1062 return NULL; 1063 } 1064 } 1065 1066 TAILQ_HEAD(dadq_head, dadq); 1067 struct dadq { 1068 TAILQ_ENTRY(dadq) dad_list; 1069 struct ifaddr *dad_ifa; 1070 int dad_count; /* max NS to send */ 1071 int dad_ns_tcount; /* # of trials to send NS */ 1072 int dad_ns_ocount; /* NS sent so far */ 1073 int dad_ns_icount; 1074 int dad_na_icount; 1075 struct callout dad_timer_ch; 1076 }; 1077 1078 static struct dadq_head dadq; 1079 static int dad_init = 0; 1080 1081 static struct dadq * 1082 nd6_dad_find(ifa) 1083 struct ifaddr *ifa; 1084 { 1085 struct dadq *dp; 1086 1087 for (dp = dadq.tqh_first; dp; dp = dp->dad_list.tqe_next) { 1088 if (dp->dad_ifa == ifa) 1089 return dp; 1090 } 1091 return NULL; 1092 } 1093 1094 static void 1095 nd6_dad_starttimer(dp, ticks) 1096 struct dadq *dp; 1097 int ticks; 1098 { 1099 1100 callout_reset(&dp->dad_timer_ch, ticks, 1101 (void (*)(void *))nd6_dad_timer, (void *)dp->dad_ifa); 1102 } 1103 1104 static void 1105 nd6_dad_stoptimer(dp) 1106 struct dadq *dp; 1107 { 1108 1109 callout_stop(&dp->dad_timer_ch); 1110 } 1111 1112 /* 1113 * Start Duplicate Address Detection (DAD) for specified interface address. 1114 */ 1115 void 1116 nd6_dad_start(ifa, delay) 1117 struct ifaddr *ifa; 1118 int delay; 1119 { 1120 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1121 struct dadq *dp; 1122 1123 if (!dad_init) { 1124 TAILQ_INIT(&dadq); 1125 dad_init++; 1126 } 1127 1128 /* 1129 * If we don't need DAD, don't do it. 1130 * There are several cases: 1131 * - DAD is disabled (ip6_dad_count == 0) 1132 * - the interface address is anycast 1133 */ 1134 if (!(ia->ia6_flags & IN6_IFF_TENTATIVE)) { 1135 log(LOG_DEBUG, 1136 "nd6_dad_start: called with non-tentative address " 1137 "%s(%s)\n", 1138 ip6_sprintf(&ia->ia_addr.sin6_addr), 1139 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1140 return; 1141 } 1142 if (ia->ia6_flags & IN6_IFF_ANYCAST) { 1143 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1144 return; 1145 } 1146 if (!ip6_dad_count) { 1147 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1148 return; 1149 } 1150 if (ifa->ifa_ifp == NULL) 1151 panic("nd6_dad_start: ifa->ifa_ifp == NULL"); 1152 if (!(ifa->ifa_ifp->if_flags & IFF_UP)) { 1153 return; 1154 } 1155 if (nd6_dad_find(ifa) != NULL) { 1156 /* DAD already in progress */ 1157 return; 1158 } 1159 1160 dp = malloc(sizeof(*dp), M_IP6NDP, M_NOWAIT); 1161 if (dp == NULL) { 1162 log(LOG_ERR, "nd6_dad_start: memory allocation failed for " 1163 "%s(%s)\n", 1164 ip6_sprintf(&ia->ia_addr.sin6_addr), 1165 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1166 return; 1167 } 1168 bzero(dp, sizeof(*dp)); 1169 callout_init(&dp->dad_timer_ch, 0); 1170 TAILQ_INSERT_TAIL(&dadq, (struct dadq *)dp, dad_list); 1171 1172 nd6log((LOG_DEBUG, "%s: starting DAD for %s\n", if_name(ifa->ifa_ifp), 1173 ip6_sprintf(&ia->ia_addr.sin6_addr))); 1174 1175 /* 1176 * Send NS packet for DAD, ip6_dad_count times. 1177 * Note that we must delay the first transmission, if this is the 1178 * first packet to be sent from the interface after interface 1179 * (re)initialization. 1180 */ 1181 dp->dad_ifa = ifa; 1182 IFAREF(ifa); /* just for safety */ 1183 dp->dad_count = ip6_dad_count; 1184 dp->dad_ns_icount = dp->dad_na_icount = 0; 1185 dp->dad_ns_ocount = dp->dad_ns_tcount = 0; 1186 if (delay == 0) { 1187 nd6_dad_ns_output(dp, ifa); 1188 nd6_dad_starttimer(dp, 1189 (long)ND_IFINFO(ifa->ifa_ifp)->retrans * hz / 1000); 1190 } else { 1191 nd6_dad_starttimer(dp, delay); 1192 } 1193 } 1194 1195 /* 1196 * terminate DAD unconditionally. used for address removals. 1197 */ 1198 void 1199 nd6_dad_stop(ifa) 1200 struct ifaddr *ifa; 1201 { 1202 struct dadq *dp; 1203 1204 if (!dad_init) 1205 return; 1206 dp = nd6_dad_find(ifa); 1207 if (!dp) { 1208 /* DAD wasn't started yet */ 1209 return; 1210 } 1211 1212 nd6_dad_stoptimer(dp); 1213 1214 TAILQ_REMOVE(&dadq, (struct dadq *)dp, dad_list); 1215 free(dp, M_IP6NDP); 1216 dp = NULL; 1217 IFAFREE(ifa); 1218 } 1219 1220 static void 1221 nd6_dad_timer(ifa) 1222 struct ifaddr *ifa; 1223 { 1224 int s; 1225 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1226 struct dadq *dp; 1227 1228 s = splnet(); /* XXX */ 1229 1230 /* Sanity check */ 1231 if (ia == NULL) { 1232 log(LOG_ERR, "nd6_dad_timer: called with null parameter\n"); 1233 goto done; 1234 } 1235 dp = nd6_dad_find(ifa); 1236 if (dp == NULL) { 1237 log(LOG_ERR, "nd6_dad_timer: DAD structure not found\n"); 1238 goto done; 1239 } 1240 if (ia->ia6_flags & IN6_IFF_DUPLICATED) { 1241 log(LOG_ERR, "nd6_dad_timer: called with duplicated address " 1242 "%s(%s)\n", 1243 ip6_sprintf(&ia->ia_addr.sin6_addr), 1244 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1245 goto done; 1246 } 1247 if ((ia->ia6_flags & IN6_IFF_TENTATIVE) == 0) { 1248 log(LOG_ERR, "nd6_dad_timer: called with non-tentative address " 1249 "%s(%s)\n", 1250 ip6_sprintf(&ia->ia_addr.sin6_addr), 1251 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1252 goto done; 1253 } 1254 1255 /* timeouted with IFF_{RUNNING,UP} check */ 1256 if (dp->dad_ns_tcount > dad_maxtry) { 1257 nd6log((LOG_INFO, "%s: could not run DAD, driver problem?\n", 1258 if_name(ifa->ifa_ifp))); 1259 1260 TAILQ_REMOVE(&dadq, (struct dadq *)dp, dad_list); 1261 free(dp, M_IP6NDP); 1262 dp = NULL; 1263 IFAFREE(ifa); 1264 goto done; 1265 } 1266 1267 /* Need more checks? */ 1268 if (dp->dad_ns_ocount < dp->dad_count) { 1269 /* 1270 * We have more NS to go. Send NS packet for DAD. 1271 */ 1272 nd6_dad_ns_output(dp, ifa); 1273 nd6_dad_starttimer(dp, 1274 (long)ND_IFINFO(ifa->ifa_ifp)->retrans * hz / 1000); 1275 } else { 1276 /* 1277 * We have transmitted sufficient number of DAD packets. 1278 * See what we've got. 1279 */ 1280 int duplicate; 1281 1282 duplicate = 0; 1283 1284 if (dp->dad_na_icount) { 1285 /* 1286 * the check is in nd6_dad_na_input(), 1287 * but just in case 1288 */ 1289 duplicate++; 1290 } 1291 1292 if (dp->dad_ns_icount) { 1293 /* We've seen NS, means DAD has failed. */ 1294 duplicate++; 1295 } 1296 1297 if (duplicate) { 1298 /* (*dp) will be freed in nd6_dad_duplicated() */ 1299 dp = NULL; 1300 nd6_dad_duplicated(ifa); 1301 } else { 1302 /* 1303 * We are done with DAD. No NA came, no NS came. 1304 * No duplicate address found. 1305 */ 1306 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1307 1308 nd6log((LOG_DEBUG, 1309 "%s: DAD complete for %s - no duplicates found\n", 1310 if_name(ifa->ifa_ifp), 1311 ip6_sprintf(&ia->ia_addr.sin6_addr))); 1312 1313 TAILQ_REMOVE(&dadq, (struct dadq *)dp, dad_list); 1314 free(dp, M_IP6NDP); 1315 dp = NULL; 1316 IFAFREE(ifa); 1317 } 1318 } 1319 1320 done: 1321 splx(s); 1322 } 1323 1324 void 1325 nd6_dad_duplicated(ifa) 1326 struct ifaddr *ifa; 1327 { 1328 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1329 struct ifnet *ifp; 1330 struct dadq *dp; 1331 1332 dp = nd6_dad_find(ifa); 1333 if (dp == NULL) { 1334 log(LOG_ERR, "nd6_dad_duplicated: DAD structure not found\n"); 1335 return; 1336 } 1337 1338 log(LOG_ERR, "%s: DAD detected duplicate IPv6 address %s: " 1339 "NS in/out=%d/%d, NA in=%d\n", 1340 if_name(ifa->ifa_ifp), ip6_sprintf(&ia->ia_addr.sin6_addr), 1341 dp->dad_ns_icount, dp->dad_ns_ocount, dp->dad_na_icount); 1342 1343 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1344 ia->ia6_flags |= IN6_IFF_DUPLICATED; 1345 1346 /* We are done with DAD, with duplicate address found. (failure) */ 1347 nd6_dad_stoptimer(dp); 1348 1349 ifp = ifa->ifa_ifp; 1350 log(LOG_ERR, "%s: DAD complete for %s - duplicate found\n", 1351 if_name(ifp), ip6_sprintf(&ia->ia_addr.sin6_addr)); 1352 log(LOG_ERR, "%s: manual intervention required\n", 1353 if_name(ifp)); 1354 1355 /* 1356 * If the address is a link-local address formed from an interface 1357 * identifier based on the hardware address which is supposed to be 1358 * uniquely assigned (e.g., EUI-64 for an Ethernet interface), IP 1359 * operation on the interface SHOULD be disabled. 1360 * [rfc2462bis-03 Section 5.4.5] 1361 */ 1362 if (IN6_IS_ADDR_LINKLOCAL(&ia->ia_addr.sin6_addr)) { 1363 struct in6_addr in6; 1364 1365 /* 1366 * To avoid over-reaction, we only apply this logic when we are 1367 * very sure that hardware addresses are supposed to be unique. 1368 */ 1369 switch (ifp->if_type) { 1370 case IFT_ETHER: 1371 case IFT_FDDI: 1372 case IFT_ATM: 1373 case IFT_IEEE1394: 1374 #ifdef IFT_IEEE80211 1375 case IFT_IEEE80211: 1376 #endif 1377 in6 = ia->ia_addr.sin6_addr; 1378 if (in6_get_hw_ifid(ifp, &in6) == 0 && 1379 IN6_ARE_ADDR_EQUAL(&ia->ia_addr.sin6_addr, &in6)) { 1380 ND_IFINFO(ifp)->flags |= ND6_IFF_IFDISABLED; 1381 log(LOG_ERR, "%s: possible hardware address " 1382 "duplication detected, disable IPv6\n", 1383 if_name(ifp)); 1384 } 1385 break; 1386 } 1387 } 1388 1389 TAILQ_REMOVE(&dadq, (struct dadq *)dp, dad_list); 1390 free(dp, M_IP6NDP); 1391 dp = NULL; 1392 IFAFREE(ifa); 1393 } 1394 1395 static void 1396 nd6_dad_ns_output(dp, ifa) 1397 struct dadq *dp; 1398 struct ifaddr *ifa; 1399 { 1400 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1401 struct ifnet *ifp = ifa->ifa_ifp; 1402 1403 dp->dad_ns_tcount++; 1404 if ((ifp->if_flags & IFF_UP) == 0) { 1405 return; 1406 } 1407 if ((ifp->if_drv_flags & IFF_DRV_RUNNING) == 0) { 1408 return; 1409 } 1410 1411 dp->dad_ns_ocount++; 1412 nd6_ns_output(ifp, NULL, &ia->ia_addr.sin6_addr, NULL, 1); 1413 } 1414 1415 static void 1416 nd6_dad_ns_input(ifa) 1417 struct ifaddr *ifa; 1418 { 1419 struct in6_ifaddr *ia; 1420 struct ifnet *ifp; 1421 const struct in6_addr *taddr6; 1422 struct dadq *dp; 1423 int duplicate; 1424 1425 if (ifa == NULL) 1426 panic("ifa == NULL in nd6_dad_ns_input"); 1427 1428 ia = (struct in6_ifaddr *)ifa; 1429 ifp = ifa->ifa_ifp; 1430 taddr6 = &ia->ia_addr.sin6_addr; 1431 duplicate = 0; 1432 dp = nd6_dad_find(ifa); 1433 1434 /* Quickhack - completely ignore DAD NS packets */ 1435 if (dad_ignore_ns) { 1436 nd6log((LOG_INFO, 1437 "nd6_dad_ns_input: ignoring DAD NS packet for " 1438 "address %s(%s)\n", ip6_sprintf(taddr6), 1439 if_name(ifa->ifa_ifp))); 1440 return; 1441 } 1442 1443 /* 1444 * if I'm yet to start DAD, someone else started using this address 1445 * first. I have a duplicate and you win. 1446 */ 1447 if (dp == NULL || dp->dad_ns_ocount == 0) 1448 duplicate++; 1449 1450 /* XXX more checks for loopback situation - see nd6_dad_timer too */ 1451 1452 if (duplicate) { 1453 dp = NULL; /* will be freed in nd6_dad_duplicated() */ 1454 nd6_dad_duplicated(ifa); 1455 } else { 1456 /* 1457 * not sure if I got a duplicate. 1458 * increment ns count and see what happens. 1459 */ 1460 if (dp) 1461 dp->dad_ns_icount++; 1462 } 1463 } 1464 1465 static void 1466 nd6_dad_na_input(ifa) 1467 struct ifaddr *ifa; 1468 { 1469 struct dadq *dp; 1470 1471 if (ifa == NULL) 1472 panic("ifa == NULL in nd6_dad_na_input"); 1473 1474 dp = nd6_dad_find(ifa); 1475 if (dp) 1476 dp->dad_na_icount++; 1477 1478 /* remove the address. */ 1479 nd6_dad_duplicated(ifa); 1480 }
Cache object: c89d60a9786694d0fad85e39308f5fc6
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