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sys/netinet6/nd6_nbr.c
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1 /* $FreeBSD: releng/6.3/sys/netinet6/nd6_nbr.c 183529 2008-10-02 00:32:59Z cperciva $ */ 2 /* $KAME: nd6_nbr.c,v 1.86 2002/01/21 02:33:04 jinmei Exp $ */ 3 4 /*- 5 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project. 6 * All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. Neither the name of the project nor the names of its contributors 17 * may be used to endorse or promote products derived from this software 18 * without specific prior written permission. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND 21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE 24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30 * SUCH DAMAGE. 31 */ 32 33 #include "opt_inet.h" 34 #include "opt_inet6.h" 35 #include "opt_ipsec.h" 36 #include "opt_carp.h" 37 38 #include <sys/param.h> 39 #include <sys/systm.h> 40 #include <sys/malloc.h> 41 #include <sys/mbuf.h> 42 #include <sys/socket.h> 43 #include <sys/sockio.h> 44 #include <sys/time.h> 45 #include <sys/kernel.h> 46 #include <sys/errno.h> 47 #include <sys/syslog.h> 48 #include <sys/queue.h> 49 #include <sys/callout.h> 50 51 #include <net/if.h> 52 #include <net/if_types.h> 53 #include <net/if_dl.h> 54 #include <net/if_var.h> 55 #include <net/route.h> 56 57 #include <netinet/in.h> 58 #include <netinet/in_var.h> 59 #include <netinet6/in6_var.h> 60 #include <netinet6/in6_ifattach.h> 61 #include <netinet/ip6.h> 62 #include <netinet6/ip6_var.h> 63 #include <netinet6/scope6_var.h> 64 #include <netinet6/nd6.h> 65 #include <netinet/icmp6.h> 66 67 #ifdef DEV_CARP 68 #include <netinet/ip_carp.h> 69 #endif 70 71 #include <net/net_osdep.h> 72 73 #define SDL(s) ((struct sockaddr_dl *)s) 74 75 struct dadq; 76 static struct dadq *nd6_dad_find __P((struct ifaddr *)); 77 static void nd6_dad_starttimer __P((struct dadq *, int)); 78 static void nd6_dad_stoptimer __P((struct dadq *)); 79 static void nd6_dad_timer __P((struct ifaddr *)); 80 static void nd6_dad_ns_output __P((struct dadq *, struct ifaddr *)); 81 static void nd6_dad_ns_input __P((struct ifaddr *)); 82 static void nd6_dad_na_input __P((struct ifaddr *)); 83 84 static int dad_ignore_ns = 0; /* ignore NS in DAD - specwise incorrect*/ 85 static int dad_maxtry = 15; /* max # of *tries* to transmit DAD packet */ 86 87 /* 88 * Input a Neighbor Solicitation Message. 89 * 90 * Based on RFC 2461 91 * Based on RFC 2462 (duplicate address detection) 92 */ 93 void 94 nd6_ns_input(m, off, icmp6len) 95 struct mbuf *m; 96 int off, icmp6len; 97 { 98 struct ifnet *ifp = m->m_pkthdr.rcvif; 99 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 100 struct nd_neighbor_solicit *nd_ns; 101 struct in6_addr saddr6 = ip6->ip6_src; 102 struct in6_addr daddr6 = ip6->ip6_dst; 103 struct in6_addr taddr6; 104 struct in6_addr myaddr6; 105 char *lladdr = NULL; 106 struct ifaddr *ifa = NULL; 107 int lladdrlen = 0; 108 int anycast = 0, proxy = 0, tentative = 0; 109 int tlladdr; 110 union nd_opts ndopts; 111 struct sockaddr_dl *proxydl = NULL; 112 113 #ifndef PULLDOWN_TEST 114 IP6_EXTHDR_CHECK(m, off, icmp6len,); 115 nd_ns = (struct nd_neighbor_solicit *)((caddr_t)ip6 + off); 116 #else 117 IP6_EXTHDR_GET(nd_ns, struct nd_neighbor_solicit *, m, off, icmp6len); 118 if (nd_ns == NULL) { 119 icmp6stat.icp6s_tooshort++; 120 return; 121 } 122 #endif 123 ip6 = mtod(m, struct ip6_hdr *); /* adjust pointer for safety */ 124 taddr6 = nd_ns->nd_ns_target; 125 if (in6_setscope(&taddr6, ifp, NULL) != 0) 126 goto bad; 127 128 if (ip6->ip6_hlim != 255) { 129 nd6log((LOG_ERR, 130 "nd6_ns_input: invalid hlim (%d) from %s to %s on %s\n", 131 ip6->ip6_hlim, ip6_sprintf(&ip6->ip6_src), 132 ip6_sprintf(&ip6->ip6_dst), if_name(ifp))); 133 goto bad; 134 } 135 136 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) { 137 /* dst has to be a solicited node multicast address. */ 138 if (daddr6.s6_addr16[0] == IPV6_ADDR_INT16_MLL && 139 /* don't check ifindex portion */ 140 daddr6.s6_addr32[1] == 0 && 141 daddr6.s6_addr32[2] == IPV6_ADDR_INT32_ONE && 142 daddr6.s6_addr8[12] == 0xff) { 143 ; /* good */ 144 } else { 145 nd6log((LOG_INFO, "nd6_ns_input: bad DAD packet " 146 "(wrong ip6 dst)\n")); 147 goto bad; 148 } 149 } else if (!nd6_onlink_ns_rfc4861) { 150 struct sockaddr_in6 src_sa6; 151 152 /* 153 * According to recent IETF discussions, it is not a good idea 154 * to accept a NS from an address which would not be deemed 155 * to be a neighbor otherwise. This point is expected to be 156 * clarified in future revisions of the specification. 157 */ 158 bzero(&src_sa6, sizeof(src_sa6)); 159 src_sa6.sin6_family = AF_INET6; 160 src_sa6.sin6_len = sizeof(src_sa6); 161 src_sa6.sin6_addr = saddr6; 162 if (!nd6_is_addr_neighbor(&src_sa6, ifp)) { 163 nd6log((LOG_INFO, "nd6_ns_input: " 164 "NS packet from non-neighbor\n")); 165 goto bad; 166 } 167 } 168 169 if (IN6_IS_ADDR_MULTICAST(&taddr6)) { 170 nd6log((LOG_INFO, "nd6_ns_input: bad NS target (multicast)\n")); 171 goto bad; 172 } 173 174 icmp6len -= sizeof(*nd_ns); 175 nd6_option_init(nd_ns + 1, icmp6len, &ndopts); 176 if (nd6_options(&ndopts) < 0) { 177 nd6log((LOG_INFO, 178 "nd6_ns_input: invalid ND option, ignored\n")); 179 /* nd6_options have incremented stats */ 180 goto freeit; 181 } 182 183 if (ndopts.nd_opts_src_lladdr) { 184 lladdr = (char *)(ndopts.nd_opts_src_lladdr + 1); 185 lladdrlen = ndopts.nd_opts_src_lladdr->nd_opt_len << 3; 186 } 187 188 if (IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_src) && lladdr) { 189 nd6log((LOG_INFO, "nd6_ns_input: bad DAD packet " 190 "(link-layer address option)\n")); 191 goto bad; 192 } 193 194 /* 195 * Attaching target link-layer address to the NA? 196 * (RFC 2461 7.2.4) 197 * 198 * NS IP dst is unicast/anycast MUST NOT add 199 * NS IP dst is solicited-node multicast MUST add 200 * 201 * In implementation, we add target link-layer address by default. 202 * We do not add one in MUST NOT cases. 203 */ 204 if (!IN6_IS_ADDR_MULTICAST(&daddr6)) 205 tlladdr = 0; 206 else 207 tlladdr = 1; 208 209 /* 210 * Target address (taddr6) must be either: 211 * (1) Valid unicast/anycast address for my receiving interface, 212 * (2) Unicast address for which I'm offering proxy service, or 213 * (3) "tentative" address on which DAD is being performed. 214 */ 215 /* (1) and (3) check. */ 216 #ifdef DEV_CARP 217 if (ifp->if_carp) 218 ifa = carp_iamatch6(ifp->if_carp, &taddr6); 219 if (ifa == NULL) 220 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &taddr6); 221 #else 222 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &taddr6); 223 #endif 224 225 /* (2) check. */ 226 if (ifa == NULL) { 227 struct rtentry *rt; 228 struct sockaddr_in6 tsin6; 229 int need_proxy; 230 231 bzero(&tsin6, sizeof tsin6); 232 tsin6.sin6_len = sizeof(struct sockaddr_in6); 233 tsin6.sin6_family = AF_INET6; 234 tsin6.sin6_addr = taddr6; 235 236 rt = rtalloc1((struct sockaddr *)&tsin6, 0, 0); 237 need_proxy = (rt && (rt->rt_flags & RTF_ANNOUNCE) != 0 && 238 rt->rt_gateway->sa_family == AF_LINK); 239 if (rt) 240 rtfree(rt); 241 if (need_proxy) { 242 /* 243 * proxy NDP for single entry 244 */ 245 ifa = (struct ifaddr *)in6ifa_ifpforlinklocal(ifp, 246 IN6_IFF_NOTREADY|IN6_IFF_ANYCAST); 247 if (ifa) { 248 proxy = 1; 249 proxydl = SDL(rt->rt_gateway); 250 } 251 } 252 } 253 if (ifa == NULL) { 254 /* 255 * We've got an NS packet, and we don't have that adddress 256 * assigned for us. We MUST silently ignore it. 257 * See RFC2461 7.2.3. 258 */ 259 goto freeit; 260 } 261 myaddr6 = *IFA_IN6(ifa); 262 anycast = ((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_ANYCAST; 263 tentative = ((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_TENTATIVE; 264 if (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_DUPLICATED) 265 goto freeit; 266 267 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) { 268 nd6log((LOG_INFO, "nd6_ns_input: lladdrlen mismatch for %s " 269 "(if %d, NS packet %d)\n", 270 ip6_sprintf(&taddr6), 271 ifp->if_addrlen, lladdrlen - 2)); 272 goto bad; 273 } 274 275 if (IN6_ARE_ADDR_EQUAL(&myaddr6, &saddr6)) { 276 nd6log((LOG_INFO, "nd6_ns_input: duplicate IP6 address %s\n", 277 ip6_sprintf(&saddr6))); 278 goto freeit; 279 } 280 281 /* 282 * We have neighbor solicitation packet, with target address equals to 283 * one of my tentative address. 284 * 285 * src addr how to process? 286 * --- --- 287 * multicast of course, invalid (rejected in ip6_input) 288 * unicast somebody is doing address resolution -> ignore 289 * unspec dup address detection 290 * 291 * The processing is defined in RFC 2462. 292 */ 293 if (tentative) { 294 /* 295 * If source address is unspecified address, it is for 296 * duplicate address detection. 297 * 298 * If not, the packet is for addess resolution; 299 * silently ignore it. 300 */ 301 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) 302 nd6_dad_ns_input(ifa); 303 304 goto freeit; 305 } 306 307 /* 308 * If the source address is unspecified address, entries must not 309 * be created or updated. 310 * It looks that sender is performing DAD. Output NA toward 311 * all-node multicast address, to tell the sender that I'm using 312 * the address. 313 * S bit ("solicited") must be zero. 314 */ 315 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) { 316 struct in6_addr in6_all; 317 318 in6_all = in6addr_linklocal_allnodes; 319 if (in6_setscope(&in6_all, ifp, NULL) != 0) 320 goto bad; 321 nd6_na_output(ifp, &in6_all, &taddr6, 322 ((anycast || proxy || !tlladdr) ? 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, 329 ND_NEIGHBOR_SOLICIT, 0); 330 331 nd6_na_output(ifp, &saddr6, &taddr6, 332 ((anycast || proxy || !tlladdr) ? 0 : ND_NA_FLAG_OVERRIDE) | 333 (ip6_forwarding ? ND_NA_FLAG_ROUTER : 0) | 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 a 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 (duplicate address detection) 355 */ 356 void 357 nd6_ns_output(ifp, daddr6, taddr6, ln, dad) 358 struct ifnet *ifp; 359 const struct in6_addr *daddr6, *taddr6; 360 struct llinfo_nd6 *ln; /* for source address determination */ 361 int dad; /* duplicate address detection */ 362 { 363 struct mbuf *m; 364 struct ip6_hdr *ip6; 365 struct nd_neighbor_solicit *nd_ns; 366 struct in6_addr *src, src_in; 367 struct ip6_moptions im6o; 368 int icmp6len; 369 int maxlen; 370 caddr_t mac; 371 struct route_in6 ro; 372 373 bzero(&ro, sizeof(ro)); 374 375 if (IN6_IS_ADDR_MULTICAST(taddr6)) 376 return; 377 378 /* estimate the size of message */ 379 maxlen = sizeof(*ip6) + sizeof(*nd_ns); 380 maxlen += (sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7; 381 if (max_linkhdr + maxlen >= MCLBYTES) { 382 #ifdef DIAGNOSTIC 383 printf("nd6_ns_output: max_linkhdr + maxlen >= MCLBYTES " 384 "(%d + %d > %d)\n", max_linkhdr, maxlen, MCLBYTES); 385 #endif 386 return; 387 } 388 389 MGETHDR(m, M_DONTWAIT, MT_DATA); 390 if (m && max_linkhdr + maxlen >= MHLEN) { 391 MCLGET(m, M_DONTWAIT); 392 if ((m->m_flags & M_EXT) == 0) { 393 m_free(m); 394 m = NULL; 395 } 396 } 397 if (m == NULL) 398 return; 399 m->m_pkthdr.rcvif = NULL; 400 401 if (daddr6 == NULL || IN6_IS_ADDR_MULTICAST(daddr6)) { 402 m->m_flags |= M_MCAST; 403 im6o.im6o_multicast_ifp = ifp; 404 im6o.im6o_multicast_hlim = 255; 405 im6o.im6o_multicast_loop = 0; 406 } 407 408 icmp6len = sizeof(*nd_ns); 409 m->m_pkthdr.len = m->m_len = sizeof(*ip6) + icmp6len; 410 m->m_data += max_linkhdr; /* or MH_ALIGN() equivalent? */ 411 412 /* fill neighbor solicitation packet */ 413 ip6 = mtod(m, struct ip6_hdr *); 414 ip6->ip6_flow = 0; 415 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 416 ip6->ip6_vfc |= IPV6_VERSION; 417 /* ip6->ip6_plen will be set later */ 418 ip6->ip6_nxt = IPPROTO_ICMPV6; 419 ip6->ip6_hlim = 255; 420 if (daddr6) 421 ip6->ip6_dst = *daddr6; 422 else { 423 ip6->ip6_dst.s6_addr16[0] = IPV6_ADDR_INT16_MLL; 424 ip6->ip6_dst.s6_addr16[1] = 0; 425 ip6->ip6_dst.s6_addr32[1] = 0; 426 ip6->ip6_dst.s6_addr32[2] = IPV6_ADDR_INT32_ONE; 427 ip6->ip6_dst.s6_addr32[3] = taddr6->s6_addr32[3]; 428 ip6->ip6_dst.s6_addr8[12] = 0xff; 429 if (in6_setscope(&ip6->ip6_dst, ifp, NULL) != 0) 430 goto bad; 431 } 432 if (!dad) { 433 /* 434 * RFC2461 7.2.2: 435 * "If the source address of the packet prompting the 436 * solicitation is the same as one of the addresses assigned 437 * to the outgoing interface, that address SHOULD be placed 438 * in the IP Source Address of the outgoing solicitation. 439 * Otherwise, any one of the addresses assigned to the 440 * interface should be used." 441 * 442 * We use the source address for the prompting packet 443 * (saddr6), if: 444 * - saddr6 is given from the caller (by giving "ln"), and 445 * - saddr6 belongs to the outgoing interface. 446 * Otherwise, we perform the source address selection as usual. 447 */ 448 struct ip6_hdr *hip6; /* hold ip6 */ 449 struct in6_addr *hsrc = NULL; 450 451 if (ln && ln->ln_hold) { 452 /* 453 * assuming every packet in ln_hold has the same IP 454 * header 455 */ 456 hip6 = mtod(ln->ln_hold, struct ip6_hdr *); 457 /* XXX pullup? */ 458 if (sizeof(*hip6) < ln->ln_hold->m_len) 459 hsrc = &hip6->ip6_src; 460 else 461 hsrc = NULL; 462 } 463 if (hsrc && in6ifa_ifpwithaddr(ifp, hsrc)) 464 src = hsrc; 465 else { 466 int error; 467 struct sockaddr_in6 dst_sa; 468 469 bzero(&dst_sa, sizeof(dst_sa)); 470 dst_sa.sin6_family = AF_INET6; 471 dst_sa.sin6_len = sizeof(dst_sa); 472 dst_sa.sin6_addr = ip6->ip6_dst; 473 474 src = in6_selectsrc(&dst_sa, NULL, 475 NULL, &ro, NULL, NULL, &error); 476 if (src == NULL) { 477 nd6log((LOG_DEBUG, 478 "nd6_ns_output: source can't be " 479 "determined: dst=%s, error=%d\n", 480 ip6_sprintf(&dst_sa.sin6_addr), error)); 481 goto bad; 482 } 483 } 484 } else { 485 /* 486 * Source address for DAD packet must always be IPv6 487 * unspecified address. (0::0) 488 * We actually don't have to 0-clear the address (we did it 489 * above), but we do so here explicitly to make the intention 490 * clearer. 491 */ 492 bzero(&src_in, sizeof(src_in)); 493 src = &src_in; 494 } 495 ip6->ip6_src = *src; 496 nd_ns = (struct nd_neighbor_solicit *)(ip6 + 1); 497 nd_ns->nd_ns_type = ND_NEIGHBOR_SOLICIT; 498 nd_ns->nd_ns_code = 0; 499 nd_ns->nd_ns_reserved = 0; 500 nd_ns->nd_ns_target = *taddr6; 501 in6_clearscope(&nd_ns->nd_ns_target); /* XXX */ 502 503 /* 504 * Add source link-layer address option. 505 * 506 * spec implementation 507 * --- --- 508 * DAD packet MUST NOT do not add the option 509 * there's no link layer address: 510 * impossible do not add the option 511 * there's link layer address: 512 * Multicast NS MUST add one add the option 513 * Unicast NS SHOULD add one add the option 514 */ 515 if (!dad && (mac = nd6_ifptomac(ifp))) { 516 int optlen = sizeof(struct nd_opt_hdr) + ifp->if_addrlen; 517 struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)(nd_ns + 1); 518 /* 8 byte alignments... */ 519 optlen = (optlen + 7) & ~7; 520 521 m->m_pkthdr.len += optlen; 522 m->m_len += optlen; 523 icmp6len += optlen; 524 bzero((caddr_t)nd_opt, optlen); 525 nd_opt->nd_opt_type = ND_OPT_SOURCE_LINKADDR; 526 nd_opt->nd_opt_len = optlen >> 3; 527 bcopy(mac, (caddr_t)(nd_opt + 1), ifp->if_addrlen); 528 } 529 530 ip6->ip6_plen = htons((u_short)icmp6len); 531 nd_ns->nd_ns_cksum = 0; 532 nd_ns->nd_ns_cksum = 533 in6_cksum(m, IPPROTO_ICMPV6, sizeof(*ip6), icmp6len); 534 535 ip6_output(m, NULL, &ro, dad ? IPV6_UNSPECSRC : 0, &im6o, NULL, NULL); 536 icmp6_ifstat_inc(ifp, ifs6_out_msg); 537 icmp6_ifstat_inc(ifp, ifs6_out_neighborsolicit); 538 icmp6stat.icp6s_outhist[ND_NEIGHBOR_SOLICIT]++; 539 540 if (ro.ro_rt) { /* we don't cache this route. */ 541 RTFREE(ro.ro_rt); 542 } 543 return; 544 545 bad: 546 if (ro.ro_rt) { 547 RTFREE(ro.ro_rt); 548 } 549 m_freem(m); 550 return; 551 } 552 553 /* 554 * Neighbor advertisement input handling. 555 * 556 * Based on RFC 2461 557 * Based on RFC 2462 (duplicate address detection) 558 * 559 * the following items are not implemented yet: 560 * - proxy advertisement delay rule (RFC2461 7.2.8, last paragraph, SHOULD) 561 * - anycast advertisement delay rule (RFC2461 7.2.7, SHOULD) 562 */ 563 void 564 nd6_na_input(m, off, icmp6len) 565 struct mbuf *m; 566 int off, icmp6len; 567 { 568 struct ifnet *ifp = m->m_pkthdr.rcvif; 569 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 570 struct nd_neighbor_advert *nd_na; 571 struct in6_addr daddr6 = ip6->ip6_dst; 572 struct in6_addr taddr6; 573 int flags; 574 int is_router; 575 int is_solicited; 576 int is_override; 577 char *lladdr = NULL; 578 int lladdrlen = 0; 579 struct ifaddr *ifa; 580 struct llinfo_nd6 *ln; 581 struct rtentry *rt; 582 struct sockaddr_dl *sdl; 583 union nd_opts ndopts; 584 585 if (ip6->ip6_hlim != 255) { 586 nd6log((LOG_ERR, 587 "nd6_na_input: invalid hlim (%d) from %s to %s on %s\n", 588 ip6->ip6_hlim, ip6_sprintf(&ip6->ip6_src), 589 ip6_sprintf(&ip6->ip6_dst), if_name(ifp))); 590 goto bad; 591 } 592 593 #ifndef PULLDOWN_TEST 594 IP6_EXTHDR_CHECK(m, off, icmp6len,); 595 nd_na = (struct nd_neighbor_advert *)((caddr_t)ip6 + off); 596 #else 597 IP6_EXTHDR_GET(nd_na, struct nd_neighbor_advert *, m, off, icmp6len); 598 if (nd_na == NULL) { 599 icmp6stat.icp6s_tooshort++; 600 return; 601 } 602 #endif 603 604 flags = nd_na->nd_na_flags_reserved; 605 is_router = ((flags & ND_NA_FLAG_ROUTER) != 0); 606 is_solicited = ((flags & ND_NA_FLAG_SOLICITED) != 0); 607 is_override = ((flags & ND_NA_FLAG_OVERRIDE) != 0); 608 609 taddr6 = nd_na->nd_na_target; 610 if (in6_setscope(&taddr6, ifp, NULL)) 611 goto bad; /* XXX: impossible */ 612 613 if (IN6_IS_ADDR_MULTICAST(&taddr6)) { 614 nd6log((LOG_ERR, 615 "nd6_na_input: invalid target address %s\n", 616 ip6_sprintf(&taddr6))); 617 goto bad; 618 } 619 if (IN6_IS_ADDR_MULTICAST(&daddr6)) 620 if (is_solicited) { 621 nd6log((LOG_ERR, 622 "nd6_na_input: a solicited adv is multicasted\n")); 623 goto bad; 624 } 625 626 icmp6len -= sizeof(*nd_na); 627 nd6_option_init(nd_na + 1, icmp6len, &ndopts); 628 if (nd6_options(&ndopts) < 0) { 629 nd6log((LOG_INFO, 630 "nd6_na_input: invalid ND option, ignored\n")); 631 /* nd6_options have incremented stats */ 632 goto freeit; 633 } 634 635 if (ndopts.nd_opts_tgt_lladdr) { 636 lladdr = (char *)(ndopts.nd_opts_tgt_lladdr + 1); 637 lladdrlen = ndopts.nd_opts_tgt_lladdr->nd_opt_len << 3; 638 } 639 640 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &taddr6); 641 642 /* 643 * Target address matches one of my interface address. 644 * 645 * If my address is tentative, this means that there's somebody 646 * already using the same address as mine. This indicates DAD failure. 647 * This is defined in RFC 2462. 648 * 649 * Otherwise, process as defined in RFC 2461. 650 */ 651 if (ifa 652 && (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_TENTATIVE)) { 653 nd6_dad_na_input(ifa); 654 goto freeit; 655 } 656 657 /* Just for safety, maybe unnecessary. */ 658 if (ifa) { 659 log(LOG_ERR, 660 "nd6_na_input: duplicate IP6 address %s\n", 661 ip6_sprintf(&taddr6)); 662 goto freeit; 663 } 664 665 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) { 666 nd6log((LOG_INFO, "nd6_na_input: lladdrlen mismatch for %s " 667 "(if %d, NA packet %d)\n", ip6_sprintf(&taddr6), 668 ifp->if_addrlen, lladdrlen - 2)); 669 goto bad; 670 } 671 672 /* 673 * If no neighbor cache entry is found, NA SHOULD silently be 674 * discarded. 675 */ 676 rt = nd6_lookup(&taddr6, 0, ifp); 677 if ((rt == NULL) || 678 ((ln = (struct llinfo_nd6 *)rt->rt_llinfo) == NULL) || 679 ((sdl = SDL(rt->rt_gateway)) == NULL)) 680 goto freeit; 681 682 if (ln->ln_state == ND6_LLINFO_INCOMPLETE) { 683 /* 684 * If the link-layer has address, and no lladdr option came, 685 * discard the packet. 686 */ 687 if (ifp->if_addrlen && lladdr == NULL) 688 goto freeit; 689 690 /* 691 * Record link-layer address, and update the state. 692 */ 693 sdl->sdl_alen = ifp->if_addrlen; 694 bcopy(lladdr, LLADDR(sdl), ifp->if_addrlen); 695 if (is_solicited) { 696 ln->ln_state = ND6_LLINFO_REACHABLE; 697 ln->ln_byhint = 0; 698 if (!ND6_LLINFO_PERMANENT(ln)) { 699 nd6_llinfo_settimer(ln, 700 (long)ND_IFINFO(rt->rt_ifp)->reachable * hz); 701 } 702 } else { 703 ln->ln_state = ND6_LLINFO_STALE; 704 nd6_llinfo_settimer(ln, (long)nd6_gctimer * hz); 705 } 706 if ((ln->ln_router = is_router) != 0) { 707 /* 708 * This means a router's state has changed from 709 * non-reachable to probably reachable, and might 710 * affect the status of associated prefixes.. 711 */ 712 pfxlist_onlink_check(); 713 } 714 } else { 715 int llchange; 716 717 /* 718 * Check if the link-layer address has changed or not. 719 */ 720 if (lladdr == NULL) 721 llchange = 0; 722 else { 723 if (sdl->sdl_alen) { 724 if (bcmp(lladdr, LLADDR(sdl), ifp->if_addrlen)) 725 llchange = 1; 726 else 727 llchange = 0; 728 } else 729 llchange = 1; 730 } 731 732 /* 733 * This is VERY complex. Look at it with care. 734 * 735 * override solicit lladdr llchange action 736 * (L: record lladdr) 737 * 738 * 0 0 n -- (2c) 739 * 0 0 y n (2b) L 740 * 0 0 y y (1) REACHABLE->STALE 741 * 0 1 n -- (2c) *->REACHABLE 742 * 0 1 y n (2b) L *->REACHABLE 743 * 0 1 y y (1) REACHABLE->STALE 744 * 1 0 n -- (2a) 745 * 1 0 y n (2a) L 746 * 1 0 y y (2a) L *->STALE 747 * 1 1 n -- (2a) *->REACHABLE 748 * 1 1 y n (2a) L *->REACHABLE 749 * 1 1 y y (2a) L *->REACHABLE 750 */ 751 if (!is_override && (lladdr != NULL && llchange)) { /* (1) */ 752 /* 753 * If state is REACHABLE, make it STALE. 754 * no other updates should be done. 755 */ 756 if (ln->ln_state == ND6_LLINFO_REACHABLE) { 757 ln->ln_state = ND6_LLINFO_STALE; 758 nd6_llinfo_settimer(ln, (long)nd6_gctimer * hz); 759 } 760 goto freeit; 761 } else if (is_override /* (2a) */ 762 || (!is_override && (lladdr != NULL && !llchange)) /* (2b) */ 763 || lladdr == NULL) { /* (2c) */ 764 /* 765 * Update link-local address, if any. 766 */ 767 if (lladdr != NULL) { 768 sdl->sdl_alen = ifp->if_addrlen; 769 bcopy(lladdr, LLADDR(sdl), ifp->if_addrlen); 770 } 771 772 /* 773 * If solicited, make the state REACHABLE. 774 * If not solicited and the link-layer address was 775 * changed, make it STALE. 776 */ 777 if (is_solicited) { 778 ln->ln_state = ND6_LLINFO_REACHABLE; 779 ln->ln_byhint = 0; 780 if (!ND6_LLINFO_PERMANENT(ln)) { 781 nd6_llinfo_settimer(ln, 782 (long)ND_IFINFO(ifp)->reachable * hz); 783 } 784 } else { 785 if (lladdr != NULL && llchange) { 786 ln->ln_state = ND6_LLINFO_STALE; 787 nd6_llinfo_settimer(ln, 788 (long)nd6_gctimer * hz); 789 } 790 } 791 } 792 793 if (ln->ln_router && !is_router) { 794 /* 795 * The peer dropped the router flag. 796 * Remove the sender from the Default Router List and 797 * update the Destination Cache entries. 798 */ 799 struct nd_defrouter *dr; 800 struct in6_addr *in6; 801 int s; 802 803 in6 = &((struct sockaddr_in6 *)rt_key(rt))->sin6_addr; 804 805 /* 806 * Lock to protect the default router list. 807 * XXX: this might be unnecessary, since this function 808 * is only called under the network software interrupt 809 * context. However, we keep it just for safety. 810 */ 811 s = splnet(); 812 dr = defrouter_lookup(in6, ifp); 813 if (dr) 814 defrtrlist_del(dr); 815 else if (!ip6_forwarding) { 816 /* 817 * Even if the neighbor is not in the default 818 * router list, the neighbor may be used 819 * as a next hop for some destinations 820 * (e.g. redirect case). So we must 821 * call rt6_flush explicitly. 822 */ 823 rt6_flush(&ip6->ip6_src, ifp); 824 } 825 splx(s); 826 } 827 ln->ln_router = is_router; 828 } 829 rt->rt_flags &= ~RTF_REJECT; 830 ln->ln_asked = 0; 831 if (ln->ln_hold) { 832 struct mbuf *m_hold, *m_hold_next; 833 834 /* 835 * reset the ln_hold in advance, to explicitly 836 * prevent a ln_hold lookup in nd6_output() 837 * (wouldn't happen, though...) 838 */ 839 for (m_hold = ln->ln_hold, ln->ln_hold = NULL; 840 m_hold; m_hold = m_hold_next) { 841 m_hold_next = m_hold->m_nextpkt; 842 m_hold->m_nextpkt = NULL; 843 /* 844 * we assume ifp is not a loopback here, so just set 845 * the 2nd argument as the 1st one. 846 */ 847 nd6_output(ifp, ifp, m_hold, 848 (struct sockaddr_in6 *)rt_key(rt), rt); 849 } 850 } 851 852 freeit: 853 m_freem(m); 854 return; 855 856 bad: 857 icmp6stat.icp6s_badna++; 858 m_freem(m); 859 } 860 861 /* 862 * Neighbor advertisement output handling. 863 * 864 * Based on RFC 2461 865 * 866 * the following items are not implemented yet: 867 * - proxy advertisement delay rule (RFC2461 7.2.8, last paragraph, SHOULD) 868 * - anycast advertisement delay rule (RFC2461 7.2.7, SHOULD) 869 */ 870 void 871 nd6_na_output(ifp, daddr6_0, taddr6, flags, tlladdr, sdl0) 872 struct ifnet *ifp; 873 const struct in6_addr *daddr6_0, *taddr6; 874 u_long flags; 875 int tlladdr; /* 1 if include target link-layer address */ 876 struct sockaddr *sdl0; /* sockaddr_dl (= proxy NA) or NULL */ 877 { 878 struct mbuf *m; 879 struct ip6_hdr *ip6; 880 struct nd_neighbor_advert *nd_na; 881 struct ip6_moptions im6o; 882 struct in6_addr *src, daddr6; 883 struct sockaddr_in6 dst_sa; 884 int icmp6len, maxlen, error; 885 caddr_t mac = NULL; 886 struct route_in6 ro; 887 888 bzero(&ro, sizeof(ro)); 889 890 daddr6 = *daddr6_0; /* make a local copy for modification */ 891 892 /* estimate the size of message */ 893 maxlen = sizeof(*ip6) + sizeof(*nd_na); 894 maxlen += (sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7; 895 if (max_linkhdr + maxlen >= MCLBYTES) { 896 #ifdef DIAGNOSTIC 897 printf("nd6_na_output: max_linkhdr + maxlen >= MCLBYTES " 898 "(%d + %d > %d)\n", max_linkhdr, maxlen, MCLBYTES); 899 #endif 900 return; 901 } 902 903 MGETHDR(m, M_DONTWAIT, MT_DATA); 904 if (m && max_linkhdr + maxlen >= MHLEN) { 905 MCLGET(m, M_DONTWAIT); 906 if ((m->m_flags & M_EXT) == 0) { 907 m_free(m); 908 m = NULL; 909 } 910 } 911 if (m == NULL) 912 return; 913 m->m_pkthdr.rcvif = NULL; 914 915 if (IN6_IS_ADDR_MULTICAST(&daddr6)) { 916 m->m_flags |= M_MCAST; 917 im6o.im6o_multicast_ifp = ifp; 918 im6o.im6o_multicast_hlim = 255; 919 im6o.im6o_multicast_loop = 0; 920 } 921 922 icmp6len = sizeof(*nd_na); 923 m->m_pkthdr.len = m->m_len = sizeof(struct ip6_hdr) + icmp6len; 924 m->m_data += max_linkhdr; /* or MH_ALIGN() equivalent? */ 925 926 /* fill neighbor advertisement packet */ 927 ip6 = mtod(m, struct ip6_hdr *); 928 ip6->ip6_flow = 0; 929 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 930 ip6->ip6_vfc |= IPV6_VERSION; 931 ip6->ip6_nxt = IPPROTO_ICMPV6; 932 ip6->ip6_hlim = 255; 933 if (IN6_IS_ADDR_UNSPECIFIED(&daddr6)) { 934 /* reply to DAD */ 935 daddr6.s6_addr16[0] = IPV6_ADDR_INT16_MLL; 936 daddr6.s6_addr16[1] = 0; 937 daddr6.s6_addr32[1] = 0; 938 daddr6.s6_addr32[2] = 0; 939 daddr6.s6_addr32[3] = IPV6_ADDR_INT32_ONE; 940 if (in6_setscope(&daddr6, ifp, NULL)) 941 goto bad; 942 943 flags &= ~ND_NA_FLAG_SOLICITED; 944 } 945 ip6->ip6_dst = daddr6; 946 bzero(&dst_sa, sizeof(struct sockaddr_in6)); 947 dst_sa.sin6_family = AF_INET6; 948 dst_sa.sin6_len = sizeof(struct sockaddr_in6); 949 dst_sa.sin6_addr = daddr6; 950 951 /* 952 * Select a source whose scope is the same as that of the dest. 953 */ 954 bcopy(&dst_sa, &ro.ro_dst, sizeof(dst_sa)); 955 src = in6_selectsrc(&dst_sa, NULL, NULL, &ro, NULL, NULL, &error); 956 if (src == NULL) { 957 nd6log((LOG_DEBUG, "nd6_na_output: source can't be " 958 "determined: dst=%s, error=%d\n", 959 ip6_sprintf(&dst_sa.sin6_addr), error)); 960 goto bad; 961 } 962 ip6->ip6_src = *src; 963 nd_na = (struct nd_neighbor_advert *)(ip6 + 1); 964 nd_na->nd_na_type = ND_NEIGHBOR_ADVERT; 965 nd_na->nd_na_code = 0; 966 nd_na->nd_na_target = *taddr6; 967 in6_clearscope(&nd_na->nd_na_target); /* XXX */ 968 969 /* 970 * "tlladdr" indicates NS's condition for adding tlladdr or not. 971 * see nd6_ns_input() for details. 972 * Basically, if NS packet is sent to unicast/anycast addr, 973 * target lladdr option SHOULD NOT be included. 974 */ 975 if (tlladdr) { 976 /* 977 * sdl0 != NULL indicates proxy NA. If we do proxy, use 978 * lladdr in sdl0. If we are not proxying (sending NA for 979 * my address) use lladdr configured for the interface. 980 */ 981 if (sdl0 == NULL) { 982 #ifdef DEV_CARP 983 if (ifp->if_carp) 984 mac = carp_macmatch6(ifp->if_carp, m, taddr6); 985 if (mac == NULL) 986 mac = nd6_ifptomac(ifp); 987 #else 988 mac = nd6_ifptomac(ifp); 989 #endif 990 } else if (sdl0->sa_family == AF_LINK) { 991 struct sockaddr_dl *sdl; 992 sdl = (struct sockaddr_dl *)sdl0; 993 if (sdl->sdl_alen == ifp->if_addrlen) 994 mac = LLADDR(sdl); 995 } 996 } 997 if (tlladdr && mac) { 998 int optlen = sizeof(struct nd_opt_hdr) + ifp->if_addrlen; 999 struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)(nd_na + 1); 1000 1001 /* roundup to 8 bytes alignment! */ 1002 optlen = (optlen + 7) & ~7; 1003 1004 m->m_pkthdr.len += optlen; 1005 m->m_len += optlen; 1006 icmp6len += optlen; 1007 bzero((caddr_t)nd_opt, optlen); 1008 nd_opt->nd_opt_type = ND_OPT_TARGET_LINKADDR; 1009 nd_opt->nd_opt_len = optlen >> 3; 1010 bcopy(mac, (caddr_t)(nd_opt + 1), ifp->if_addrlen); 1011 } else 1012 flags &= ~ND_NA_FLAG_OVERRIDE; 1013 1014 ip6->ip6_plen = htons((u_short)icmp6len); 1015 nd_na->nd_na_flags_reserved = flags; 1016 nd_na->nd_na_cksum = 0; 1017 nd_na->nd_na_cksum = 1018 in6_cksum(m, IPPROTO_ICMPV6, sizeof(struct ip6_hdr), icmp6len); 1019 1020 ip6_output(m, NULL, &ro, 0, &im6o, NULL, NULL); 1021 icmp6_ifstat_inc(ifp, ifs6_out_msg); 1022 icmp6_ifstat_inc(ifp, ifs6_out_neighboradvert); 1023 icmp6stat.icp6s_outhist[ND_NEIGHBOR_ADVERT]++; 1024 1025 if (ro.ro_rt) { /* we don't cache this route. */ 1026 RTFREE(ro.ro_rt); 1027 } 1028 return; 1029 1030 bad: 1031 if (ro.ro_rt) { 1032 RTFREE(ro.ro_rt); 1033 } 1034 m_freem(m); 1035 return; 1036 } 1037 1038 caddr_t 1039 nd6_ifptomac(ifp) 1040 struct ifnet *ifp; 1041 { 1042 switch (ifp->if_type) { 1043 case IFT_ARCNET: 1044 case IFT_ETHER: 1045 case IFT_FDDI: 1046 case IFT_IEEE1394: 1047 #ifdef IFT_L2VLAN 1048 case IFT_L2VLAN: 1049 #endif 1050 #ifdef IFT_IEEE80211 1051 case IFT_IEEE80211: 1052 #endif 1053 #ifdef IFT_CARP 1054 case IFT_CARP: 1055 #endif 1056 case IFT_BRIDGE: 1057 case IFT_ISO88025: 1058 return IF_LLADDR(ifp); 1059 default: 1060 return NULL; 1061 } 1062 } 1063 1064 TAILQ_HEAD(dadq_head, dadq); 1065 struct dadq { 1066 TAILQ_ENTRY(dadq) dad_list; 1067 struct ifaddr *dad_ifa; 1068 int dad_count; /* max NS to send */ 1069 int dad_ns_tcount; /* # of trials to send NS */ 1070 int dad_ns_ocount; /* NS sent so far */ 1071 int dad_ns_icount; 1072 int dad_na_icount; 1073 struct callout dad_timer_ch; 1074 }; 1075 1076 static struct dadq_head dadq; 1077 static int dad_init = 0; 1078 1079 static struct dadq * 1080 nd6_dad_find(ifa) 1081 struct ifaddr *ifa; 1082 { 1083 struct dadq *dp; 1084 1085 for (dp = dadq.tqh_first; dp; dp = dp->dad_list.tqe_next) { 1086 if (dp->dad_ifa == ifa) 1087 return dp; 1088 } 1089 return NULL; 1090 } 1091 1092 static void 1093 nd6_dad_starttimer(dp, ticks) 1094 struct dadq *dp; 1095 int ticks; 1096 { 1097 1098 callout_reset(&dp->dad_timer_ch, ticks, 1099 (void (*) __P((void *)))nd6_dad_timer, (void *)dp->dad_ifa); 1100 } 1101 1102 static void 1103 nd6_dad_stoptimer(dp) 1104 struct dadq *dp; 1105 { 1106 1107 callout_stop(&dp->dad_timer_ch); 1108 } 1109 1110 /* 1111 * Start Duplicate Address Detection (DAD) for specified interface address. 1112 */ 1113 void 1114 nd6_dad_start(ifa, delay) 1115 struct ifaddr *ifa; 1116 int delay; 1117 { 1118 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1119 struct dadq *dp; 1120 1121 if (!dad_init) { 1122 TAILQ_INIT(&dadq); 1123 dad_init++; 1124 } 1125 1126 /* 1127 * If we don't need DAD, don't do it. 1128 * There are several cases: 1129 * - DAD is disabled (ip6_dad_count == 0) 1130 * - the interface address is anycast 1131 */ 1132 if (!(ia->ia6_flags & IN6_IFF_TENTATIVE)) { 1133 log(LOG_DEBUG, 1134 "nd6_dad_start: called with non-tentative address " 1135 "%s(%s)\n", 1136 ip6_sprintf(&ia->ia_addr.sin6_addr), 1137 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1138 return; 1139 } 1140 if (ia->ia6_flags & IN6_IFF_ANYCAST) { 1141 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1142 return; 1143 } 1144 if (!ip6_dad_count) { 1145 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1146 return; 1147 } 1148 if (ifa->ifa_ifp == NULL) 1149 panic("nd6_dad_start: ifa->ifa_ifp == NULL"); 1150 if (!(ifa->ifa_ifp->if_flags & IFF_UP)) { 1151 return; 1152 } 1153 if (nd6_dad_find(ifa) != NULL) { 1154 /* DAD already in progress */ 1155 return; 1156 } 1157 1158 dp = malloc(sizeof(*dp), M_IP6NDP, M_NOWAIT); 1159 if (dp == NULL) { 1160 log(LOG_ERR, "nd6_dad_start: memory allocation failed for " 1161 "%s(%s)\n", 1162 ip6_sprintf(&ia->ia_addr.sin6_addr), 1163 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1164 return; 1165 } 1166 bzero(dp, sizeof(*dp)); 1167 callout_init(&dp->dad_timer_ch, 0); 1168 TAILQ_INSERT_TAIL(&dadq, (struct dadq *)dp, dad_list); 1169 1170 nd6log((LOG_DEBUG, "%s: starting DAD for %s\n", if_name(ifa->ifa_ifp), 1171 ip6_sprintf(&ia->ia_addr.sin6_addr))); 1172 1173 /* 1174 * Send NS packet for DAD, ip6_dad_count times. 1175 * Note that we must delay the first transmission, if this is the 1176 * first packet to be sent from the interface after interface 1177 * (re)initialization. 1178 */ 1179 dp->dad_ifa = ifa; 1180 IFAREF(ifa); /* just for safety */ 1181 dp->dad_count = ip6_dad_count; 1182 dp->dad_ns_icount = dp->dad_na_icount = 0; 1183 dp->dad_ns_ocount = dp->dad_ns_tcount = 0; 1184 if (delay == 0) { 1185 nd6_dad_ns_output(dp, ifa); 1186 nd6_dad_starttimer(dp, 1187 (long)ND_IFINFO(ifa->ifa_ifp)->retrans * hz / 1000); 1188 } else { 1189 nd6_dad_starttimer(dp, delay); 1190 } 1191 } 1192 1193 /* 1194 * terminate DAD unconditionally. used for address removals. 1195 */ 1196 void 1197 nd6_dad_stop(ifa) 1198 struct ifaddr *ifa; 1199 { 1200 struct dadq *dp; 1201 1202 if (!dad_init) 1203 return; 1204 dp = nd6_dad_find(ifa); 1205 if (!dp) { 1206 /* DAD wasn't started yet */ 1207 return; 1208 } 1209 1210 nd6_dad_stoptimer(dp); 1211 1212 TAILQ_REMOVE(&dadq, (struct dadq *)dp, dad_list); 1213 free(dp, M_IP6NDP); 1214 dp = NULL; 1215 IFAFREE(ifa); 1216 } 1217 1218 static void 1219 nd6_dad_timer(ifa) 1220 struct ifaddr *ifa; 1221 { 1222 int s; 1223 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1224 struct dadq *dp; 1225 1226 s = splnet(); /* XXX */ 1227 1228 /* Sanity check */ 1229 if (ia == NULL) { 1230 log(LOG_ERR, "nd6_dad_timer: called with null parameter\n"); 1231 goto done; 1232 } 1233 dp = nd6_dad_find(ifa); 1234 if (dp == NULL) { 1235 log(LOG_ERR, "nd6_dad_timer: DAD structure not found\n"); 1236 goto done; 1237 } 1238 if (ia->ia6_flags & IN6_IFF_DUPLICATED) { 1239 log(LOG_ERR, "nd6_dad_timer: called with duplicated address " 1240 "%s(%s)\n", 1241 ip6_sprintf(&ia->ia_addr.sin6_addr), 1242 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1243 goto done; 1244 } 1245 if ((ia->ia6_flags & IN6_IFF_TENTATIVE) == 0) { 1246 log(LOG_ERR, "nd6_dad_timer: called with non-tentative address " 1247 "%s(%s)\n", 1248 ip6_sprintf(&ia->ia_addr.sin6_addr), 1249 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1250 goto done; 1251 } 1252 1253 /* timeouted with IFF_{RUNNING,UP} check */ 1254 if (dp->dad_ns_tcount > dad_maxtry) { 1255 nd6log((LOG_INFO, "%s: could not run DAD, driver problem?\n", 1256 if_name(ifa->ifa_ifp))); 1257 1258 TAILQ_REMOVE(&dadq, (struct dadq *)dp, dad_list); 1259 free(dp, M_IP6NDP); 1260 dp = NULL; 1261 IFAFREE(ifa); 1262 goto done; 1263 } 1264 1265 /* Need more checks? */ 1266 if (dp->dad_ns_ocount < dp->dad_count) { 1267 /* 1268 * We have more NS to go. Send NS packet for DAD. 1269 */ 1270 nd6_dad_ns_output(dp, ifa); 1271 nd6_dad_starttimer(dp, 1272 (long)ND_IFINFO(ifa->ifa_ifp)->retrans * hz / 1000); 1273 } else { 1274 /* 1275 * We have transmitted sufficient number of DAD packets. 1276 * See what we've got. 1277 */ 1278 int duplicate; 1279 1280 duplicate = 0; 1281 1282 if (dp->dad_na_icount) { 1283 /* 1284 * the check is in nd6_dad_na_input(), 1285 * but just in case 1286 */ 1287 duplicate++; 1288 } 1289 1290 if (dp->dad_ns_icount) { 1291 /* We've seen NS, means DAD has failed. */ 1292 duplicate++; 1293 } 1294 1295 if (duplicate) { 1296 /* (*dp) will be freed in nd6_dad_duplicated() */ 1297 dp = NULL; 1298 nd6_dad_duplicated(ifa); 1299 } else { 1300 /* 1301 * We are done with DAD. No NA came, no NS came. 1302 * No duplicate address found. 1303 */ 1304 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1305 1306 nd6log((LOG_DEBUG, 1307 "%s: DAD complete for %s - no duplicates found\n", 1308 if_name(ifa->ifa_ifp), 1309 ip6_sprintf(&ia->ia_addr.sin6_addr))); 1310 1311 TAILQ_REMOVE(&dadq, (struct dadq *)dp, dad_list); 1312 free(dp, M_IP6NDP); 1313 dp = NULL; 1314 IFAFREE(ifa); 1315 } 1316 } 1317 1318 done: 1319 splx(s); 1320 } 1321 1322 void 1323 nd6_dad_duplicated(ifa) 1324 struct ifaddr *ifa; 1325 { 1326 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1327 struct ifnet *ifp; 1328 struct dadq *dp; 1329 1330 dp = nd6_dad_find(ifa); 1331 if (dp == NULL) { 1332 log(LOG_ERR, "nd6_dad_duplicated: DAD structure not found\n"); 1333 return; 1334 } 1335 1336 log(LOG_ERR, "%s: DAD detected duplicate IPv6 address %s: " 1337 "NS in/out=%d/%d, NA in=%d\n", 1338 if_name(ifa->ifa_ifp), ip6_sprintf(&ia->ia_addr.sin6_addr), 1339 dp->dad_ns_icount, dp->dad_ns_ocount, dp->dad_na_icount); 1340 1341 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1342 ia->ia6_flags |= IN6_IFF_DUPLICATED; 1343 1344 /* We are done with DAD, with duplicate address found. (failure) */ 1345 nd6_dad_stoptimer(dp); 1346 1347 ifp = ifa->ifa_ifp; 1348 log(LOG_ERR, "%s: DAD complete for %s - duplicate found\n", 1349 if_name(ifp), ip6_sprintf(&ia->ia_addr.sin6_addr)); 1350 log(LOG_ERR, "%s: manual intervention required\n", 1351 if_name(ifp)); 1352 1353 /* 1354 * If the address is a link-local address formed from an interface 1355 * identifier based on the hardware address which is supposed to be 1356 * uniquely assigned (e.g., EUI-64 for an Ethernet interface), IP 1357 * operation on the interface SHOULD be disabled. 1358 * [rfc2462bis-03 Section 5.4.5] 1359 */ 1360 if (IN6_IS_ADDR_LINKLOCAL(&ia->ia_addr.sin6_addr)) { 1361 struct in6_addr in6; 1362 1363 /* 1364 * To avoid over-reaction, we only apply this logic when we are 1365 * very sure that hardware addresses are supposed to be unique. 1366 */ 1367 switch (ifp->if_type) { 1368 case IFT_ETHER: 1369 case IFT_FDDI: 1370 case IFT_ATM: 1371 case IFT_IEEE1394: 1372 #ifdef IFT_IEEE80211 1373 case IFT_IEEE80211: 1374 #endif 1375 in6 = ia->ia_addr.sin6_addr; 1376 if (in6_get_hw_ifid(ifp, &in6) == 0 && 1377 IN6_ARE_ADDR_EQUAL(&ia->ia_addr.sin6_addr, &in6)) { 1378 ND_IFINFO(ifp)->flags |= ND6_IFF_IFDISABLED; 1379 log(LOG_ERR, "%s: possible hardware address " 1380 "duplication detected, disable IPv6\n", 1381 if_name(ifp)); 1382 } 1383 break; 1384 } 1385 } 1386 1387 TAILQ_REMOVE(&dadq, (struct dadq *)dp, dad_list); 1388 free(dp, M_IP6NDP); 1389 dp = NULL; 1390 IFAFREE(ifa); 1391 } 1392 1393 static void 1394 nd6_dad_ns_output(dp, ifa) 1395 struct dadq *dp; 1396 struct ifaddr *ifa; 1397 { 1398 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1399 struct ifnet *ifp = ifa->ifa_ifp; 1400 1401 dp->dad_ns_tcount++; 1402 if ((ifp->if_flags & IFF_UP) == 0) { 1403 return; 1404 } 1405 if ((ifp->if_drv_flags & IFF_DRV_RUNNING) == 0) { 1406 return; 1407 } 1408 1409 dp->dad_ns_ocount++; 1410 nd6_ns_output(ifp, NULL, &ia->ia_addr.sin6_addr, NULL, 1); 1411 } 1412 1413 static void 1414 nd6_dad_ns_input(ifa) 1415 struct ifaddr *ifa; 1416 { 1417 struct in6_ifaddr *ia; 1418 struct ifnet *ifp; 1419 const struct in6_addr *taddr6; 1420 struct dadq *dp; 1421 int duplicate; 1422 1423 if (ifa == NULL) 1424 panic("ifa == NULL in nd6_dad_ns_input"); 1425 1426 ia = (struct in6_ifaddr *)ifa; 1427 ifp = ifa->ifa_ifp; 1428 taddr6 = &ia->ia_addr.sin6_addr; 1429 duplicate = 0; 1430 dp = nd6_dad_find(ifa); 1431 1432 /* Quickhack - completely ignore DAD NS packets */ 1433 if (dad_ignore_ns) { 1434 nd6log((LOG_INFO, 1435 "nd6_dad_ns_input: ignoring DAD NS packet for " 1436 "address %s(%s)\n", ip6_sprintf(taddr6), 1437 if_name(ifa->ifa_ifp))); 1438 return; 1439 } 1440 1441 /* 1442 * if I'm yet to start DAD, someone else started using this address 1443 * first. I have a duplicate and you win. 1444 */ 1445 if (dp == NULL || dp->dad_ns_ocount == 0) 1446 duplicate++; 1447 1448 /* XXX more checks for loopback situation - see nd6_dad_timer too */ 1449 1450 if (duplicate) { 1451 dp = NULL; /* will be freed in nd6_dad_duplicated() */ 1452 nd6_dad_duplicated(ifa); 1453 } else { 1454 /* 1455 * not sure if I got a duplicate. 1456 * increment ns count and see what happens. 1457 */ 1458 if (dp) 1459 dp->dad_ns_icount++; 1460 } 1461 } 1462 1463 static void 1464 nd6_dad_na_input(ifa) 1465 struct ifaddr *ifa; 1466 { 1467 struct dadq *dp; 1468 1469 if (ifa == NULL) 1470 panic("ifa == NULL in nd6_dad_na_input"); 1471 1472 dp = nd6_dad_find(ifa); 1473 if (dp) 1474 dp->dad_na_icount++; 1475 1476 /* remove the address. */ 1477 nd6_dad_duplicated(ifa); 1478 }
Cache object: e954afd0f0ec41a131869749cf151115
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