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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/7.3/sys/netinet6/nd6_nbr.c 202914 2010-01-24 10:08:54Z bz $"); 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 #define SDL(s) ((struct sockaddr_dl *)s) 74 75 struct dadq; 76 static struct dadq *nd6_dad_find(struct ifaddr *); 77 static void nd6_dad_starttimer(struct dadq *, int); 78 static void nd6_dad_stoptimer(struct dadq *); 79 static void nd6_dad_timer(struct ifaddr *); 80 static void nd6_dad_ns_output(struct dadq *, struct ifaddr *); 81 static void nd6_dad_ns_input(struct ifaddr *); 82 static void nd6_dad_na_input(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(struct mbuf *m, int off, int icmp6len) 95 { 96 struct ifnet *ifp = m->m_pkthdr.rcvif; 97 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 98 struct nd_neighbor_solicit *nd_ns; 99 struct in6_addr saddr6 = ip6->ip6_src; 100 struct in6_addr daddr6 = ip6->ip6_dst; 101 struct in6_addr taddr6; 102 struct in6_addr myaddr6; 103 char *lladdr = NULL; 104 struct ifaddr *ifa = NULL; 105 int lladdrlen = 0; 106 int anycast = 0, proxy = 0, tentative = 0; 107 int tlladdr; 108 union nd_opts ndopts; 109 struct sockaddr_dl *proxydl = NULL; 110 char ip6bufs[INET6_ADDRSTRLEN], ip6bufd[INET6_ADDRSTRLEN]; 111 112 #ifndef PULLDOWN_TEST 113 IP6_EXTHDR_CHECK(m, off, icmp6len,); 114 nd_ns = (struct nd_neighbor_solicit *)((caddr_t)ip6 + off); 115 #else 116 IP6_EXTHDR_GET(nd_ns, struct nd_neighbor_solicit *, m, off, icmp6len); 117 if (nd_ns == NULL) { 118 icmp6stat.icp6s_tooshort++; 119 return; 120 } 121 #endif 122 ip6 = mtod(m, struct ip6_hdr *); /* adjust pointer for safety */ 123 taddr6 = nd_ns->nd_ns_target; 124 if (in6_setscope(&taddr6, ifp, NULL) != 0) 125 goto bad; 126 127 if (ip6->ip6_hlim != 255) { 128 nd6log((LOG_ERR, 129 "nd6_ns_input: invalid hlim (%d) from %s to %s on %s\n", 130 ip6->ip6_hlim, ip6_sprintf(ip6bufs, &ip6->ip6_src), 131 ip6_sprintf(ip6bufd, &ip6->ip6_dst), if_name(ifp))); 132 goto bad; 133 } 134 135 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) { 136 /* dst has to be a solicited node multicast address. */ 137 if (daddr6.s6_addr16[0] == IPV6_ADDR_INT16_MLL && 138 /* don't check ifindex portion */ 139 daddr6.s6_addr32[1] == 0 && 140 daddr6.s6_addr32[2] == IPV6_ADDR_INT32_ONE && 141 daddr6.s6_addr8[12] == 0xff) { 142 ; /* good */ 143 } else { 144 nd6log((LOG_INFO, "nd6_ns_input: bad DAD packet " 145 "(wrong ip6 dst)\n")); 146 goto bad; 147 } 148 } else if (!nd6_onlink_ns_rfc4861) { 149 struct sockaddr_in6 src_sa6; 150 151 /* 152 * According to recent IETF discussions, it is not a good idea 153 * to accept a NS from an address which would not be deemed 154 * to be a neighbor otherwise. This point is expected to be 155 * clarified in future revisions of the specification. 156 */ 157 bzero(&src_sa6, sizeof(src_sa6)); 158 src_sa6.sin6_family = AF_INET6; 159 src_sa6.sin6_len = sizeof(src_sa6); 160 src_sa6.sin6_addr = saddr6; 161 if (!nd6_is_addr_neighbor(&src_sa6, ifp)) { 162 nd6log((LOG_INFO, "nd6_ns_input: " 163 "NS packet from non-neighbor\n")); 164 goto bad; 165 } 166 } 167 168 if (IN6_IS_ADDR_MULTICAST(&taddr6)) { 169 nd6log((LOG_INFO, "nd6_ns_input: bad NS target (multicast)\n")); 170 goto bad; 171 } 172 173 icmp6len -= sizeof(*nd_ns); 174 nd6_option_init(nd_ns + 1, icmp6len, &ndopts); 175 if (nd6_options(&ndopts) < 0) { 176 nd6log((LOG_INFO, 177 "nd6_ns_input: invalid ND option, ignored\n")); 178 /* nd6_options have incremented stats */ 179 goto freeit; 180 } 181 182 if (ndopts.nd_opts_src_lladdr) { 183 lladdr = (char *)(ndopts.nd_opts_src_lladdr + 1); 184 lladdrlen = ndopts.nd_opts_src_lladdr->nd_opt_len << 3; 185 } 186 187 if (IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_src) && lladdr) { 188 nd6log((LOG_INFO, "nd6_ns_input: bad DAD packet " 189 "(link-layer address option)\n")); 190 goto bad; 191 } 192 193 /* 194 * Attaching target link-layer address to the NA? 195 * (RFC 2461 7.2.4) 196 * 197 * NS IP dst is unicast/anycast MUST NOT add 198 * NS IP dst is solicited-node multicast MUST add 199 * 200 * In implementation, we add target link-layer address by default. 201 * We do not add one in MUST NOT cases. 202 */ 203 if (!IN6_IS_ADDR_MULTICAST(&daddr6)) 204 tlladdr = 0; 205 else 206 tlladdr = 1; 207 208 /* 209 * Target address (taddr6) must be either: 210 * (1) Valid unicast/anycast address for my receiving interface, 211 * (2) Unicast address for which I'm offering proxy service, or 212 * (3) "tentative" address on which DAD is being performed. 213 */ 214 /* (1) and (3) check. */ 215 #ifdef DEV_CARP 216 if (ifp->if_carp) 217 ifa = carp_iamatch6(ifp->if_carp, &taddr6); 218 if (ifa == NULL) 219 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &taddr6); 220 #else 221 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &taddr6); 222 #endif 223 224 /* (2) check. */ 225 if (ifa == NULL) { 226 struct rtentry *rt; 227 struct sockaddr_in6 tsin6; 228 int need_proxy; 229 230 bzero(&tsin6, sizeof tsin6); 231 tsin6.sin6_len = sizeof(struct sockaddr_in6); 232 tsin6.sin6_family = AF_INET6; 233 tsin6.sin6_addr = taddr6; 234 235 rt = rtalloc1((struct sockaddr *)&tsin6, 0, 0); 236 need_proxy = (rt && (rt->rt_flags & RTF_ANNOUNCE) != 0 && 237 rt->rt_gateway->sa_family == AF_LINK); 238 if (rt) 239 RTFREE_LOCKED(rt); 240 if (need_proxy) { 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 } 252 if (ifa == NULL) { 253 /* 254 * We've got an NS packet, and we don't have that adddress 255 * assigned for us. We MUST silently ignore it. 256 * See RFC2461 7.2.3. 257 */ 258 goto freeit; 259 } 260 myaddr6 = *IFA_IN6(ifa); 261 anycast = ((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_ANYCAST; 262 tentative = ((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_TENTATIVE; 263 if (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_DUPLICATED) 264 goto freeit; 265 266 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) { 267 nd6log((LOG_INFO, "nd6_ns_input: lladdrlen mismatch for %s " 268 "(if %d, NS packet %d)\n", 269 ip6_sprintf(ip6bufs, &taddr6), 270 ifp->if_addrlen, lladdrlen - 2)); 271 goto bad; 272 } 273 274 if (IN6_ARE_ADDR_EQUAL(&myaddr6, &saddr6)) { 275 nd6log((LOG_INFO, "nd6_ns_input: duplicate IP6 address %s\n", 276 ip6_sprintf(ip6bufs, &saddr6))); 277 goto freeit; 278 } 279 280 /* 281 * We have neighbor solicitation packet, with target address equals to 282 * one of my tentative address. 283 * 284 * src addr how to process? 285 * --- --- 286 * multicast of course, invalid (rejected in ip6_input) 287 * unicast somebody is doing address resolution -> ignore 288 * unspec dup address detection 289 * 290 * The processing is defined in RFC 2462. 291 */ 292 if (tentative) { 293 /* 294 * If source address is unspecified address, it is for 295 * duplicate address detection. 296 * 297 * If not, the packet is for addess resolution; 298 * silently ignore it. 299 */ 300 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) 301 nd6_dad_ns_input(ifa); 302 303 goto freeit; 304 } 305 306 /* 307 * If the source address is unspecified address, entries must not 308 * be created or updated. 309 * It looks that sender is performing DAD. Output NA toward 310 * all-node multicast address, to tell the sender that I'm using 311 * the address. 312 * S bit ("solicited") must be zero. 313 */ 314 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) { 315 struct in6_addr in6_all; 316 317 in6_all = in6addr_linklocal_allnodes; 318 if (in6_setscope(&in6_all, ifp, NULL) != 0) 319 goto bad; 320 nd6_na_output(ifp, &in6_all, &taddr6, 321 ((anycast || proxy || !tlladdr) ? 0 : ND_NA_FLAG_OVERRIDE) | 322 (ip6_forwarding ? ND_NA_FLAG_ROUTER : 0), 323 tlladdr, (struct sockaddr *)proxydl); 324 goto freeit; 325 } 326 327 nd6_cache_lladdr(ifp, &saddr6, lladdr, lladdrlen, 328 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) | ND_NA_FLAG_SOLICITED, 333 tlladdr, (struct sockaddr *)proxydl); 334 freeit: 335 m_freem(m); 336 return; 337 338 bad: 339 nd6log((LOG_ERR, "nd6_ns_input: src=%s\n", 340 ip6_sprintf(ip6bufs, &saddr6))); 341 nd6log((LOG_ERR, "nd6_ns_input: dst=%s\n", 342 ip6_sprintf(ip6bufs, &daddr6))); 343 nd6log((LOG_ERR, "nd6_ns_input: tgt=%s\n", 344 ip6_sprintf(ip6bufs, &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 * ln - for source address determination 359 * dad - duplicate address detection 360 */ 361 void 362 nd6_ns_output(struct ifnet *ifp, const struct in6_addr *daddr6, 363 const struct in6_addr *taddr6, struct llinfo_nd6 *ln, int dad) 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 error = in6_selectsrc(&dst_sa, NULL, 477 NULL, &ro, NULL, NULL, &src_in); 478 if (error) { 479 char ip6buf[INET6_ADDRSTRLEN]; 480 nd6log((LOG_DEBUG, 481 "nd6_ns_output: source can't be " 482 "determined: dst=%s, error=%d\n", 483 ip6_sprintf(ip6buf, &dst_sa.sin6_addr), 484 error)); 485 goto bad; 486 } 487 src = &src_in; 488 } 489 } else { 490 /* 491 * Source address for DAD packet must always be IPv6 492 * unspecified address. (0::0) 493 * We actually don't have to 0-clear the address (we did it 494 * above), but we do so here explicitly to make the intention 495 * clearer. 496 */ 497 bzero(&src_in, sizeof(src_in)); 498 src = &src_in; 499 } 500 ip6->ip6_src = *src; 501 nd_ns = (struct nd_neighbor_solicit *)(ip6 + 1); 502 nd_ns->nd_ns_type = ND_NEIGHBOR_SOLICIT; 503 nd_ns->nd_ns_code = 0; 504 nd_ns->nd_ns_reserved = 0; 505 nd_ns->nd_ns_target = *taddr6; 506 in6_clearscope(&nd_ns->nd_ns_target); /* XXX */ 507 508 /* 509 * Add source link-layer address option. 510 * 511 * spec implementation 512 * --- --- 513 * DAD packet MUST NOT do not add the option 514 * there's no link layer address: 515 * impossible do not add the option 516 * there's link layer address: 517 * Multicast NS MUST add one add the option 518 * Unicast NS SHOULD add one add the option 519 */ 520 if (!dad && (mac = nd6_ifptomac(ifp))) { 521 int optlen = sizeof(struct nd_opt_hdr) + ifp->if_addrlen; 522 struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)(nd_ns + 1); 523 /* 8 byte alignments... */ 524 optlen = (optlen + 7) & ~7; 525 526 m->m_pkthdr.len += optlen; 527 m->m_len += optlen; 528 icmp6len += optlen; 529 bzero((caddr_t)nd_opt, optlen); 530 nd_opt->nd_opt_type = ND_OPT_SOURCE_LINKADDR; 531 nd_opt->nd_opt_len = optlen >> 3; 532 bcopy(mac, (caddr_t)(nd_opt + 1), ifp->if_addrlen); 533 } 534 535 ip6->ip6_plen = htons((u_short)icmp6len); 536 nd_ns->nd_ns_cksum = 0; 537 nd_ns->nd_ns_cksum = 538 in6_cksum(m, IPPROTO_ICMPV6, sizeof(*ip6), icmp6len); 539 540 ip6_output(m, NULL, &ro, dad ? IPV6_UNSPECSRC : 0, &im6o, NULL, NULL); 541 icmp6_ifstat_inc(ifp, ifs6_out_msg); 542 icmp6_ifstat_inc(ifp, ifs6_out_neighborsolicit); 543 icmp6stat.icp6s_outhist[ND_NEIGHBOR_SOLICIT]++; 544 545 if (ro.ro_rt) { /* we don't cache this route. */ 546 RTFREE(ro.ro_rt); 547 } 548 return; 549 550 bad: 551 if (ro.ro_rt) { 552 RTFREE(ro.ro_rt); 553 } 554 m_freem(m); 555 return; 556 } 557 558 /* 559 * Neighbor advertisement input handling. 560 * 561 * Based on RFC 2461 562 * Based on RFC 2462 (duplicate address detection) 563 * 564 * the following items are not implemented yet: 565 * - proxy advertisement delay rule (RFC2461 7.2.8, last paragraph, SHOULD) 566 * - anycast advertisement delay rule (RFC2461 7.2.7, SHOULD) 567 */ 568 void 569 nd6_na_input(struct mbuf *m, int off, int icmp6len) 570 { 571 struct ifnet *ifp = m->m_pkthdr.rcvif; 572 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 573 struct nd_neighbor_advert *nd_na; 574 struct in6_addr daddr6 = ip6->ip6_dst; 575 struct in6_addr taddr6; 576 int flags; 577 int is_router; 578 int is_solicited; 579 int is_override; 580 char *lladdr = NULL; 581 int lladdrlen = 0; 582 struct ifaddr *ifa; 583 struct llinfo_nd6 *ln; 584 struct rtentry *rt; 585 struct sockaddr_dl *sdl; 586 union nd_opts ndopts; 587 char ip6bufs[INET6_ADDRSTRLEN], ip6bufd[INET6_ADDRSTRLEN]; 588 589 if (ip6->ip6_hlim != 255) { 590 nd6log((LOG_ERR, 591 "nd6_na_input: invalid hlim (%d) from %s to %s on %s\n", 592 ip6->ip6_hlim, ip6_sprintf(ip6bufs, &ip6->ip6_src), 593 ip6_sprintf(ip6bufd, &ip6->ip6_dst), if_name(ifp))); 594 goto bad; 595 } 596 597 #ifndef PULLDOWN_TEST 598 IP6_EXTHDR_CHECK(m, off, icmp6len,); 599 nd_na = (struct nd_neighbor_advert *)((caddr_t)ip6 + off); 600 #else 601 IP6_EXTHDR_GET(nd_na, struct nd_neighbor_advert *, m, off, icmp6len); 602 if (nd_na == NULL) { 603 icmp6stat.icp6s_tooshort++; 604 return; 605 } 606 #endif 607 608 flags = nd_na->nd_na_flags_reserved; 609 is_router = ((flags & ND_NA_FLAG_ROUTER) != 0); 610 is_solicited = ((flags & ND_NA_FLAG_SOLICITED) != 0); 611 is_override = ((flags & ND_NA_FLAG_OVERRIDE) != 0); 612 613 taddr6 = nd_na->nd_na_target; 614 if (in6_setscope(&taddr6, ifp, NULL)) 615 goto bad; /* XXX: impossible */ 616 617 if (IN6_IS_ADDR_MULTICAST(&taddr6)) { 618 nd6log((LOG_ERR, 619 "nd6_na_input: invalid target address %s\n", 620 ip6_sprintf(ip6bufs, &taddr6))); 621 goto bad; 622 } 623 if (IN6_IS_ADDR_MULTICAST(&daddr6)) 624 if (is_solicited) { 625 nd6log((LOG_ERR, 626 "nd6_na_input: a solicited adv is multicasted\n")); 627 goto bad; 628 } 629 630 icmp6len -= sizeof(*nd_na); 631 nd6_option_init(nd_na + 1, icmp6len, &ndopts); 632 if (nd6_options(&ndopts) < 0) { 633 nd6log((LOG_INFO, 634 "nd6_na_input: invalid ND option, ignored\n")); 635 /* nd6_options have incremented stats */ 636 goto freeit; 637 } 638 639 if (ndopts.nd_opts_tgt_lladdr) { 640 lladdr = (char *)(ndopts.nd_opts_tgt_lladdr + 1); 641 lladdrlen = ndopts.nd_opts_tgt_lladdr->nd_opt_len << 3; 642 } 643 644 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &taddr6); 645 646 /* 647 * Target address matches one of my interface address. 648 * 649 * If my address is tentative, this means that there's somebody 650 * already using the same address as mine. This indicates DAD failure. 651 * This is defined in RFC 2462. 652 * 653 * Otherwise, process as defined in RFC 2461. 654 */ 655 if (ifa 656 && (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_TENTATIVE)) { 657 nd6_dad_na_input(ifa); 658 goto freeit; 659 } 660 661 /* Just for safety, maybe unnecessary. */ 662 if (ifa) { 663 log(LOG_ERR, 664 "nd6_na_input: duplicate IP6 address %s\n", 665 ip6_sprintf(ip6bufs, &taddr6)); 666 goto freeit; 667 } 668 669 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) { 670 nd6log((LOG_INFO, "nd6_na_input: lladdrlen mismatch for %s " 671 "(if %d, NA packet %d)\n", ip6_sprintf(ip6bufs, &taddr6), 672 ifp->if_addrlen, lladdrlen - 2)); 673 goto bad; 674 } 675 676 /* 677 * If no neighbor cache entry is found, NA SHOULD silently be 678 * discarded. 679 */ 680 rt = nd6_lookup(&taddr6, 0, ifp); 681 if ((rt == NULL) || 682 ((ln = (struct llinfo_nd6 *)rt->rt_llinfo) == NULL) || 683 ((sdl = SDL(rt->rt_gateway)) == NULL)) 684 goto freeit; 685 686 if (ln->ln_state == ND6_LLINFO_INCOMPLETE) { 687 /* 688 * If the link-layer has address, and no lladdr option came, 689 * discard the packet. 690 */ 691 if (ifp->if_addrlen && lladdr == NULL) 692 goto freeit; 693 694 /* 695 * Record link-layer address, and update the state. 696 */ 697 sdl->sdl_alen = ifp->if_addrlen; 698 bcopy(lladdr, LLADDR(sdl), ifp->if_addrlen); 699 if (is_solicited) { 700 ln->ln_state = ND6_LLINFO_REACHABLE; 701 ln->ln_byhint = 0; 702 if (!ND6_LLINFO_PERMANENT(ln)) { 703 nd6_llinfo_settimer(ln, 704 (long)ND_IFINFO(rt->rt_ifp)->reachable * hz); 705 } 706 } else { 707 ln->ln_state = ND6_LLINFO_STALE; 708 nd6_llinfo_settimer(ln, (long)nd6_gctimer * hz); 709 } 710 if ((ln->ln_router = is_router) != 0) { 711 /* 712 * This means a router's state has changed from 713 * non-reachable to probably reachable, and might 714 * affect the status of associated prefixes.. 715 */ 716 pfxlist_onlink_check(); 717 } 718 } else { 719 int llchange; 720 721 /* 722 * Check if the link-layer address has changed or not. 723 */ 724 if (lladdr == NULL) 725 llchange = 0; 726 else { 727 if (sdl->sdl_alen) { 728 if (bcmp(lladdr, LLADDR(sdl), ifp->if_addrlen)) 729 llchange = 1; 730 else 731 llchange = 0; 732 } else 733 llchange = 1; 734 } 735 736 /* 737 * This is VERY complex. Look at it with care. 738 * 739 * override solicit lladdr llchange action 740 * (L: record lladdr) 741 * 742 * 0 0 n -- (2c) 743 * 0 0 y n (2b) L 744 * 0 0 y y (1) REACHABLE->STALE 745 * 0 1 n -- (2c) *->REACHABLE 746 * 0 1 y n (2b) L *->REACHABLE 747 * 0 1 y y (1) REACHABLE->STALE 748 * 1 0 n -- (2a) 749 * 1 0 y n (2a) L 750 * 1 0 y y (2a) L *->STALE 751 * 1 1 n -- (2a) *->REACHABLE 752 * 1 1 y n (2a) L *->REACHABLE 753 * 1 1 y y (2a) L *->REACHABLE 754 */ 755 if (!is_override && (lladdr != NULL && llchange)) { /* (1) */ 756 /* 757 * If state is REACHABLE, make it STALE. 758 * no other updates should be done. 759 */ 760 if (ln->ln_state == ND6_LLINFO_REACHABLE) { 761 ln->ln_state = ND6_LLINFO_STALE; 762 nd6_llinfo_settimer(ln, (long)nd6_gctimer * hz); 763 } 764 goto freeit; 765 } else if (is_override /* (2a) */ 766 || (!is_override && (lladdr != NULL && !llchange)) /* (2b) */ 767 || lladdr == NULL) { /* (2c) */ 768 /* 769 * Update link-local address, if any. 770 */ 771 if (lladdr != NULL) { 772 sdl->sdl_alen = ifp->if_addrlen; 773 bcopy(lladdr, LLADDR(sdl), ifp->if_addrlen); 774 } 775 776 /* 777 * If solicited, make the state REACHABLE. 778 * If not solicited and the link-layer address was 779 * changed, make it STALE. 780 */ 781 if (is_solicited) { 782 ln->ln_state = ND6_LLINFO_REACHABLE; 783 ln->ln_byhint = 0; 784 if (!ND6_LLINFO_PERMANENT(ln)) { 785 nd6_llinfo_settimer(ln, 786 (long)ND_IFINFO(ifp)->reachable * hz); 787 } 788 } else { 789 if (lladdr != NULL && llchange) { 790 ln->ln_state = ND6_LLINFO_STALE; 791 nd6_llinfo_settimer(ln, 792 (long)nd6_gctimer * hz); 793 } 794 } 795 } 796 797 if (ln->ln_router && !is_router) { 798 /* 799 * The peer dropped the router flag. 800 * Remove the sender from the Default Router List and 801 * update the Destination Cache entries. 802 */ 803 struct nd_defrouter *dr; 804 struct in6_addr *in6; 805 int s; 806 807 in6 = &((struct sockaddr_in6 *)rt_key(rt))->sin6_addr; 808 809 /* 810 * Lock to protect the default router list. 811 * XXX: this might be unnecessary, since this function 812 * is only called under the network software interrupt 813 * context. However, we keep it just for safety. 814 */ 815 s = splnet(); 816 dr = defrouter_lookup(in6, ifp); 817 if (dr) 818 defrtrlist_del(dr); 819 else if (!ip6_forwarding) { 820 /* 821 * Even if the neighbor is not in the default 822 * router list, the neighbor may be used 823 * as a next hop for some destinations 824 * (e.g. redirect case). So we must 825 * call rt6_flush explicitly. 826 */ 827 rt6_flush(&ip6->ip6_src, ifp); 828 } 829 splx(s); 830 } 831 ln->ln_router = is_router; 832 } 833 rt->rt_flags &= ~RTF_REJECT; 834 ln->ln_asked = 0; 835 if (ln->ln_hold) { 836 struct mbuf *m_hold, *m_hold_next; 837 838 /* 839 * reset the ln_hold in advance, to explicitly 840 * prevent a ln_hold lookup in nd6_output() 841 * (wouldn't happen, though...) 842 */ 843 for (m_hold = ln->ln_hold; 844 m_hold; m_hold = m_hold_next) { 845 m_hold_next = m_hold->m_nextpkt; 846 m_hold->m_nextpkt = NULL; 847 /* 848 * we assume ifp is not a loopback here, so just set 849 * the 2nd argument as the 1st one. 850 */ 851 nd6_output(ifp, ifp, m_hold, 852 (struct sockaddr_in6 *)rt_key(rt), rt); 853 } 854 ln->ln_hold = NULL; 855 } 856 857 freeit: 858 m_freem(m); 859 return; 860 861 bad: 862 icmp6stat.icp6s_badna++; 863 m_freem(m); 864 } 865 866 /* 867 * Neighbor advertisement output handling. 868 * 869 * Based on RFC 2461 870 * 871 * the following items are not implemented yet: 872 * - proxy advertisement delay rule (RFC2461 7.2.8, last paragraph, SHOULD) 873 * - anycast advertisement delay rule (RFC2461 7.2.7, SHOULD) 874 * 875 * tlladdr - 1 if include target link-layer address 876 * sdl0 - sockaddr_dl (= proxy NA) or NULL 877 */ 878 void 879 nd6_na_output(struct ifnet *ifp, const struct in6_addr *daddr6_0, 880 const struct in6_addr *taddr6, u_long flags, int tlladdr, 881 struct sockaddr *sdl0) 882 { 883 struct mbuf *m; 884 struct ip6_hdr *ip6; 885 struct nd_neighbor_advert *nd_na; 886 struct ip6_moptions im6o; 887 struct in6_addr src, daddr6; 888 struct sockaddr_in6 dst_sa; 889 int icmp6len, maxlen, error; 890 caddr_t mac = NULL; 891 struct route_in6 ro; 892 893 bzero(&ro, sizeof(ro)); 894 895 daddr6 = *daddr6_0; /* make a local copy for modification */ 896 897 /* estimate the size of message */ 898 maxlen = sizeof(*ip6) + sizeof(*nd_na); 899 maxlen += (sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7; 900 if (max_linkhdr + maxlen >= MCLBYTES) { 901 #ifdef DIAGNOSTIC 902 printf("nd6_na_output: max_linkhdr + maxlen >= MCLBYTES " 903 "(%d + %d > %d)\n", max_linkhdr, maxlen, MCLBYTES); 904 #endif 905 return; 906 } 907 908 MGETHDR(m, M_DONTWAIT, MT_DATA); 909 if (m && max_linkhdr + maxlen >= MHLEN) { 910 MCLGET(m, M_DONTWAIT); 911 if ((m->m_flags & M_EXT) == 0) { 912 m_free(m); 913 m = NULL; 914 } 915 } 916 if (m == NULL) 917 return; 918 m->m_pkthdr.rcvif = NULL; 919 920 if (IN6_IS_ADDR_MULTICAST(&daddr6)) { 921 m->m_flags |= M_MCAST; 922 im6o.im6o_multicast_ifp = ifp; 923 im6o.im6o_multicast_hlim = 255; 924 im6o.im6o_multicast_loop = 0; 925 } 926 927 icmp6len = sizeof(*nd_na); 928 m->m_pkthdr.len = m->m_len = sizeof(struct ip6_hdr) + icmp6len; 929 m->m_data += max_linkhdr; /* or MH_ALIGN() equivalent? */ 930 931 /* fill neighbor advertisement packet */ 932 ip6 = mtod(m, struct ip6_hdr *); 933 ip6->ip6_flow = 0; 934 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 935 ip6->ip6_vfc |= IPV6_VERSION; 936 ip6->ip6_nxt = IPPROTO_ICMPV6; 937 ip6->ip6_hlim = 255; 938 if (IN6_IS_ADDR_UNSPECIFIED(&daddr6)) { 939 /* reply to DAD */ 940 daddr6.s6_addr16[0] = IPV6_ADDR_INT16_MLL; 941 daddr6.s6_addr16[1] = 0; 942 daddr6.s6_addr32[1] = 0; 943 daddr6.s6_addr32[2] = 0; 944 daddr6.s6_addr32[3] = IPV6_ADDR_INT32_ONE; 945 if (in6_setscope(&daddr6, ifp, NULL)) 946 goto bad; 947 948 flags &= ~ND_NA_FLAG_SOLICITED; 949 } 950 ip6->ip6_dst = daddr6; 951 bzero(&dst_sa, sizeof(struct sockaddr_in6)); 952 dst_sa.sin6_family = AF_INET6; 953 dst_sa.sin6_len = sizeof(struct sockaddr_in6); 954 dst_sa.sin6_addr = daddr6; 955 956 /* 957 * Select a source whose scope is the same as that of the dest. 958 */ 959 bcopy(&dst_sa, &ro.ro_dst, sizeof(dst_sa)); 960 error = in6_selectsrc(&dst_sa, NULL, NULL, &ro, NULL, NULL, &src); 961 if (error) { 962 char ip6buf[INET6_ADDRSTRLEN]; 963 nd6log((LOG_DEBUG, "nd6_na_output: source can't be " 964 "determined: dst=%s, error=%d\n", 965 ip6_sprintf(ip6buf, &dst_sa.sin6_addr), error)); 966 goto bad; 967 } 968 ip6->ip6_src = src; 969 nd_na = (struct nd_neighbor_advert *)(ip6 + 1); 970 nd_na->nd_na_type = ND_NEIGHBOR_ADVERT; 971 nd_na->nd_na_code = 0; 972 nd_na->nd_na_target = *taddr6; 973 in6_clearscope(&nd_na->nd_na_target); /* XXX */ 974 975 /* 976 * "tlladdr" indicates NS's condition for adding tlladdr or not. 977 * see nd6_ns_input() for details. 978 * Basically, if NS packet is sent to unicast/anycast addr, 979 * target lladdr option SHOULD NOT be included. 980 */ 981 if (tlladdr) { 982 /* 983 * sdl0 != NULL indicates proxy NA. If we do proxy, use 984 * lladdr in sdl0. If we are not proxying (sending NA for 985 * my address) use lladdr configured for the interface. 986 */ 987 if (sdl0 == NULL) { 988 #ifdef DEV_CARP 989 if (ifp->if_carp) 990 mac = carp_macmatch6(ifp->if_carp, m, taddr6); 991 if (mac == NULL) 992 mac = nd6_ifptomac(ifp); 993 #else 994 mac = nd6_ifptomac(ifp); 995 #endif 996 } else if (sdl0->sa_family == AF_LINK) { 997 struct sockaddr_dl *sdl; 998 sdl = (struct sockaddr_dl *)sdl0; 999 if (sdl->sdl_alen == ifp->if_addrlen) 1000 mac = LLADDR(sdl); 1001 } 1002 } 1003 if (tlladdr && mac) { 1004 int optlen = sizeof(struct nd_opt_hdr) + ifp->if_addrlen; 1005 struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)(nd_na + 1); 1006 1007 /* roundup to 8 bytes alignment! */ 1008 optlen = (optlen + 7) & ~7; 1009 1010 m->m_pkthdr.len += optlen; 1011 m->m_len += optlen; 1012 icmp6len += optlen; 1013 bzero((caddr_t)nd_opt, optlen); 1014 nd_opt->nd_opt_type = ND_OPT_TARGET_LINKADDR; 1015 nd_opt->nd_opt_len = optlen >> 3; 1016 bcopy(mac, (caddr_t)(nd_opt + 1), ifp->if_addrlen); 1017 } else 1018 flags &= ~ND_NA_FLAG_OVERRIDE; 1019 1020 ip6->ip6_plen = htons((u_short)icmp6len); 1021 nd_na->nd_na_flags_reserved = flags; 1022 nd_na->nd_na_cksum = 0; 1023 nd_na->nd_na_cksum = 1024 in6_cksum(m, IPPROTO_ICMPV6, sizeof(struct ip6_hdr), icmp6len); 1025 1026 ip6_output(m, NULL, &ro, 0, &im6o, NULL, NULL); 1027 icmp6_ifstat_inc(ifp, ifs6_out_msg); 1028 icmp6_ifstat_inc(ifp, ifs6_out_neighboradvert); 1029 icmp6stat.icp6s_outhist[ND_NEIGHBOR_ADVERT]++; 1030 1031 if (ro.ro_rt) { /* we don't cache this route. */ 1032 RTFREE(ro.ro_rt); 1033 } 1034 return; 1035 1036 bad: 1037 if (ro.ro_rt) { 1038 RTFREE(ro.ro_rt); 1039 } 1040 m_freem(m); 1041 return; 1042 } 1043 1044 caddr_t 1045 nd6_ifptomac(struct ifnet *ifp) 1046 { 1047 switch (ifp->if_type) { 1048 case IFT_ARCNET: 1049 case IFT_ETHER: 1050 case IFT_FDDI: 1051 case IFT_IEEE1394: 1052 #ifdef IFT_L2VLAN 1053 case IFT_L2VLAN: 1054 #endif 1055 #ifdef IFT_IEEE80211 1056 case IFT_IEEE80211: 1057 #endif 1058 #ifdef IFT_CARP 1059 case IFT_CARP: 1060 #endif 1061 case IFT_BRIDGE: 1062 case IFT_ISO88025: 1063 return IF_LLADDR(ifp); 1064 default: 1065 return NULL; 1066 } 1067 } 1068 1069 TAILQ_HEAD(dadq_head, dadq); 1070 struct dadq { 1071 TAILQ_ENTRY(dadq) dad_list; 1072 struct ifaddr *dad_ifa; 1073 int dad_count; /* max NS to send */ 1074 int dad_ns_tcount; /* # of trials to send NS */ 1075 int dad_ns_ocount; /* NS sent so far */ 1076 int dad_ns_icount; 1077 int dad_na_icount; 1078 struct callout dad_timer_ch; 1079 }; 1080 1081 static struct dadq_head dadq; 1082 static int dad_init = 0; 1083 1084 static struct dadq * 1085 nd6_dad_find(struct ifaddr *ifa) 1086 { 1087 struct dadq *dp; 1088 1089 for (dp = dadq.tqh_first; dp; dp = dp->dad_list.tqe_next) { 1090 if (dp->dad_ifa == ifa) 1091 return dp; 1092 } 1093 return NULL; 1094 } 1095 1096 static void 1097 nd6_dad_starttimer(struct dadq *dp, 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(struct dadq *dp) 1106 { 1107 1108 callout_stop(&dp->dad_timer_ch); 1109 } 1110 1111 /* 1112 * Start Duplicate Address Detection (DAD) for specified interface address. 1113 */ 1114 void 1115 nd6_dad_start(struct ifaddr *ifa, int delay) 1116 { 1117 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1118 struct dadq *dp; 1119 char ip6buf[INET6_ADDRSTRLEN]; 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(ip6buf, &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(ip6buf, &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(ip6buf, &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(struct ifaddr *ifa) 1198 { 1199 struct dadq *dp; 1200 1201 if (!dad_init) 1202 return; 1203 dp = nd6_dad_find(ifa); 1204 if (!dp) { 1205 /* DAD wasn't started yet */ 1206 return; 1207 } 1208 1209 nd6_dad_stoptimer(dp); 1210 1211 TAILQ_REMOVE(&dadq, (struct dadq *)dp, dad_list); 1212 free(dp, M_IP6NDP); 1213 dp = NULL; 1214 IFAFREE(ifa); 1215 } 1216 1217 static void 1218 nd6_dad_timer(struct ifaddr *ifa) 1219 { 1220 int s; 1221 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1222 struct dadq *dp; 1223 char ip6buf[INET6_ADDRSTRLEN]; 1224 1225 s = splnet(); /* XXX */ 1226 1227 /* Sanity check */ 1228 if (ia == NULL) { 1229 log(LOG_ERR, "nd6_dad_timer: called with null parameter\n"); 1230 goto done; 1231 } 1232 dp = nd6_dad_find(ifa); 1233 if (dp == NULL) { 1234 log(LOG_ERR, "nd6_dad_timer: DAD structure not found\n"); 1235 goto done; 1236 } 1237 if (ia->ia6_flags & IN6_IFF_DUPLICATED) { 1238 log(LOG_ERR, "nd6_dad_timer: called with duplicated address " 1239 "%s(%s)\n", 1240 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr), 1241 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1242 goto done; 1243 } 1244 if ((ia->ia6_flags & IN6_IFF_TENTATIVE) == 0) { 1245 log(LOG_ERR, "nd6_dad_timer: called with non-tentative address " 1246 "%s(%s)\n", 1247 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr), 1248 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1249 goto done; 1250 } 1251 1252 /* timeouted with IFF_{RUNNING,UP} check */ 1253 if (dp->dad_ns_tcount > dad_maxtry) { 1254 nd6log((LOG_INFO, "%s: could not run DAD, driver problem?\n", 1255 if_name(ifa->ifa_ifp))); 1256 1257 TAILQ_REMOVE(&dadq, (struct dadq *)dp, dad_list); 1258 free(dp, M_IP6NDP); 1259 dp = NULL; 1260 IFAFREE(ifa); 1261 goto done; 1262 } 1263 1264 /* Need more checks? */ 1265 if (dp->dad_ns_ocount < dp->dad_count) { 1266 /* 1267 * We have more NS to go. Send NS packet for DAD. 1268 */ 1269 nd6_dad_ns_output(dp, ifa); 1270 nd6_dad_starttimer(dp, 1271 (long)ND_IFINFO(ifa->ifa_ifp)->retrans * hz / 1000); 1272 } else { 1273 /* 1274 * We have transmitted sufficient number of DAD packets. 1275 * See what we've got. 1276 */ 1277 int duplicate; 1278 1279 duplicate = 0; 1280 1281 if (dp->dad_na_icount) { 1282 /* 1283 * the check is in nd6_dad_na_input(), 1284 * but just in case 1285 */ 1286 duplicate++; 1287 } 1288 1289 if (dp->dad_ns_icount) { 1290 /* We've seen NS, means DAD has failed. */ 1291 duplicate++; 1292 } 1293 1294 if (duplicate) { 1295 /* (*dp) will be freed in nd6_dad_duplicated() */ 1296 dp = NULL; 1297 nd6_dad_duplicated(ifa); 1298 } else { 1299 /* 1300 * We are done with DAD. No NA came, no NS came. 1301 * No duplicate address found. 1302 */ 1303 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1304 1305 nd6log((LOG_DEBUG, 1306 "%s: DAD complete for %s - no duplicates found\n", 1307 if_name(ifa->ifa_ifp), 1308 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr))); 1309 1310 TAILQ_REMOVE(&dadq, (struct dadq *)dp, dad_list); 1311 free(dp, M_IP6NDP); 1312 dp = NULL; 1313 IFAFREE(ifa); 1314 } 1315 } 1316 1317 done: 1318 splx(s); 1319 } 1320 1321 void 1322 nd6_dad_duplicated(struct ifaddr *ifa) 1323 { 1324 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1325 struct ifnet *ifp; 1326 struct dadq *dp; 1327 char ip6buf[INET6_ADDRSTRLEN]; 1328 1329 dp = nd6_dad_find(ifa); 1330 if (dp == NULL) { 1331 log(LOG_ERR, "nd6_dad_duplicated: DAD structure not found\n"); 1332 return; 1333 } 1334 1335 log(LOG_ERR, "%s: DAD detected duplicate IPv6 address %s: " 1336 "NS in/out=%d/%d, NA in=%d\n", 1337 if_name(ifa->ifa_ifp), ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr), 1338 dp->dad_ns_icount, dp->dad_ns_ocount, dp->dad_na_icount); 1339 1340 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1341 ia->ia6_flags |= IN6_IFF_DUPLICATED; 1342 1343 /* We are done with DAD, with duplicate address found. (failure) */ 1344 nd6_dad_stoptimer(dp); 1345 1346 ifp = ifa->ifa_ifp; 1347 log(LOG_ERR, "%s: DAD complete for %s - duplicate found\n", 1348 if_name(ifp), ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr)); 1349 log(LOG_ERR, "%s: manual intervention required\n", 1350 if_name(ifp)); 1351 1352 /* 1353 * If the address is a link-local address formed from an interface 1354 * identifier based on the hardware address which is supposed to be 1355 * uniquely assigned (e.g., EUI-64 for an Ethernet interface), IP 1356 * operation on the interface SHOULD be disabled. 1357 * [rfc2462bis-03 Section 5.4.5] 1358 */ 1359 if (IN6_IS_ADDR_LINKLOCAL(&ia->ia_addr.sin6_addr)) { 1360 struct in6_addr in6; 1361 1362 /* 1363 * To avoid over-reaction, we only apply this logic when we are 1364 * very sure that hardware addresses are supposed to be unique. 1365 */ 1366 switch (ifp->if_type) { 1367 case IFT_ETHER: 1368 case IFT_FDDI: 1369 case IFT_ATM: 1370 case IFT_IEEE1394: 1371 #ifdef IFT_IEEE80211 1372 case IFT_IEEE80211: 1373 #endif 1374 in6 = ia->ia_addr.sin6_addr; 1375 if (in6_get_hw_ifid(ifp, &in6) == 0 && 1376 IN6_ARE_ADDR_EQUAL(&ia->ia_addr.sin6_addr, &in6)) { 1377 ND_IFINFO(ifp)->flags |= ND6_IFF_IFDISABLED; 1378 log(LOG_ERR, "%s: possible hardware address " 1379 "duplication detected, disable IPv6\n", 1380 if_name(ifp)); 1381 } 1382 break; 1383 } 1384 } 1385 1386 TAILQ_REMOVE(&dadq, (struct dadq *)dp, dad_list); 1387 free(dp, M_IP6NDP); 1388 dp = NULL; 1389 IFAFREE(ifa); 1390 } 1391 1392 static void 1393 nd6_dad_ns_output(struct dadq *dp, struct ifaddr *ifa) 1394 { 1395 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1396 struct ifnet *ifp = ifa->ifa_ifp; 1397 1398 dp->dad_ns_tcount++; 1399 if ((ifp->if_flags & IFF_UP) == 0) { 1400 return; 1401 } 1402 if ((ifp->if_drv_flags & IFF_DRV_RUNNING) == 0) { 1403 return; 1404 } 1405 1406 dp->dad_ns_ocount++; 1407 nd6_ns_output(ifp, NULL, &ia->ia_addr.sin6_addr, NULL, 1); 1408 } 1409 1410 static void 1411 nd6_dad_ns_input(struct ifaddr *ifa) 1412 { 1413 struct in6_ifaddr *ia; 1414 struct ifnet *ifp; 1415 const struct in6_addr *taddr6; 1416 struct dadq *dp; 1417 int duplicate; 1418 1419 if (ifa == NULL) 1420 panic("ifa == NULL in nd6_dad_ns_input"); 1421 1422 ia = (struct in6_ifaddr *)ifa; 1423 ifp = ifa->ifa_ifp; 1424 taddr6 = &ia->ia_addr.sin6_addr; 1425 duplicate = 0; 1426 dp = nd6_dad_find(ifa); 1427 1428 /* Quickhack - completely ignore DAD NS packets */ 1429 if (dad_ignore_ns) { 1430 char ip6buf[INET6_ADDRSTRLEN]; 1431 nd6log((LOG_INFO, 1432 "nd6_dad_ns_input: ignoring DAD NS packet for " 1433 "address %s(%s)\n", ip6_sprintf(ip6buf, taddr6), 1434 if_name(ifa->ifa_ifp))); 1435 return; 1436 } 1437 1438 /* 1439 * if I'm yet to start DAD, someone else started using this address 1440 * first. I have a duplicate and you win. 1441 */ 1442 if (dp == NULL || dp->dad_ns_ocount == 0) 1443 duplicate++; 1444 1445 /* XXX more checks for loopback situation - see nd6_dad_timer too */ 1446 1447 if (duplicate) { 1448 dp = NULL; /* will be freed in nd6_dad_duplicated() */ 1449 nd6_dad_duplicated(ifa); 1450 } else { 1451 /* 1452 * not sure if I got a duplicate. 1453 * increment ns count and see what happens. 1454 */ 1455 if (dp) 1456 dp->dad_ns_icount++; 1457 } 1458 } 1459 1460 static void 1461 nd6_dad_na_input(struct ifaddr *ifa) 1462 { 1463 struct dadq *dp; 1464 1465 if (ifa == NULL) 1466 panic("ifa == NULL in nd6_dad_na_input"); 1467 1468 dp = nd6_dad_find(ifa); 1469 if (dp) 1470 dp->dad_na_icount++; 1471 1472 /* remove the address. */ 1473 nd6_dad_duplicated(ifa); 1474 }
Cache object: d0f7b198ada298c05883a35955255fe2
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