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("$FreeBSD$"); 34 35 #include "opt_inet.h" 36 #include "opt_inet6.h" 37 #include "opt_ipsec.h" 38 #include "opt_mpath.h" 39 40 #include <sys/param.h> 41 #include <sys/systm.h> 42 #include <sys/malloc.h> 43 #include <sys/lock.h> 44 #include <sys/rwlock.h> 45 #include <sys/mbuf.h> 46 #include <sys/socket.h> 47 #include <sys/sockio.h> 48 #include <sys/time.h> 49 #include <sys/kernel.h> 50 #include <sys/errno.h> 51 #include <sys/syslog.h> 52 #include <sys/queue.h> 53 #include <sys/callout.h> 54 55 #include <net/if.h> 56 #include <net/if_types.h> 57 #include <net/if_dl.h> 58 #include <net/if_var.h> 59 #include <net/route.h> 60 #ifdef RADIX_MPATH 61 #include <net/radix_mpath.h> 62 #endif 63 64 #include <netinet/in.h> 65 #include <netinet/in_var.h> 66 #include <net/if_llatbl.h> 67 #define L3_ADDR_SIN6(le) ((struct sockaddr_in6 *) L3_ADDR(le)) 68 #include <netinet6/in6_var.h> 69 #include <netinet6/in6_ifattach.h> 70 #include <netinet/ip6.h> 71 #include <netinet6/ip6_var.h> 72 #include <netinet6/scope6_var.h> 73 #include <netinet6/nd6.h> 74 #include <netinet/icmp6.h> 75 76 #define SDL(s) ((struct sockaddr_dl *)s) 77 78 struct dadq; 79 static struct dadq *nd6_dad_find(struct ifaddr *); 80 static void nd6_dad_starttimer(struct dadq *, int); 81 static void nd6_dad_stoptimer(struct dadq *); 82 static void nd6_dad_timer(struct dadq *); 83 static void nd6_dad_ns_output(struct dadq *, struct ifaddr *); 84 static void nd6_dad_ns_input(struct ifaddr *); 85 static void nd6_dad_na_input(struct ifaddr *); 86 87 struct ifaddr *(*carp_iamatch6_p)(struct ifnet *, struct in6_addr *); 88 caddr_t (*carp_macmatch6_p)(struct ifnet *, struct mbuf *, 89 const struct in6_addr *); 90 91 VNET_DEFINE(int, dad_ignore_ns) = 0; /* ignore NS in DAD - specwise incorrect*/ 92 VNET_DEFINE(int, dad_maxtry) = 15; /* max # of *tries* to transmit DAD packet */ 93 #define V_dad_ignore_ns VNET(dad_ignore_ns) 94 #define V_dad_maxtry VNET(dad_maxtry) 95 96 /* 97 * Input a Neighbor Solicitation Message. 98 * 99 * Based on RFC 2461 100 * Based on RFC 2462 (duplicate address detection) 101 */ 102 void 103 nd6_ns_input(struct mbuf *m, int off, int icmp6len) 104 { 105 struct ifnet *ifp = m->m_pkthdr.rcvif; 106 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 107 struct nd_neighbor_solicit *nd_ns; 108 struct in6_addr saddr6 = ip6->ip6_src; 109 struct in6_addr daddr6 = ip6->ip6_dst; 110 struct in6_addr taddr6; 111 struct in6_addr myaddr6; 112 char *lladdr = NULL; 113 struct ifaddr *ifa = NULL; 114 int lladdrlen = 0; 115 int anycast = 0, proxy = 0, tentative = 0; 116 int tlladdr; 117 union nd_opts ndopts; 118 struct sockaddr_dl *proxydl = NULL; 119 char ip6bufs[INET6_ADDRSTRLEN], ip6bufd[INET6_ADDRSTRLEN]; 120 121 #ifndef PULLDOWN_TEST 122 IP6_EXTHDR_CHECK(m, off, icmp6len,); 123 nd_ns = (struct nd_neighbor_solicit *)((caddr_t)ip6 + off); 124 #else 125 IP6_EXTHDR_GET(nd_ns, struct nd_neighbor_solicit *, m, off, icmp6len); 126 if (nd_ns == NULL) { 127 ICMP6STAT_INC(icp6s_tooshort); 128 return; 129 } 130 #endif 131 ip6 = mtod(m, struct ip6_hdr *); /* adjust pointer for safety */ 132 taddr6 = nd_ns->nd_ns_target; 133 if (in6_setscope(&taddr6, ifp, NULL) != 0) 134 goto bad; 135 136 if (ip6->ip6_hlim != 255) { 137 nd6log((LOG_ERR, 138 "nd6_ns_input: invalid hlim (%d) from %s to %s on %s\n", 139 ip6->ip6_hlim, ip6_sprintf(ip6bufs, &ip6->ip6_src), 140 ip6_sprintf(ip6bufd, &ip6->ip6_dst), if_name(ifp))); 141 goto bad; 142 } 143 144 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) { 145 /* dst has to be a solicited node multicast address. */ 146 if (daddr6.s6_addr16[0] == IPV6_ADDR_INT16_MLL && 147 /* don't check ifindex portion */ 148 daddr6.s6_addr32[1] == 0 && 149 daddr6.s6_addr32[2] == IPV6_ADDR_INT32_ONE && 150 daddr6.s6_addr8[12] == 0xff) { 151 ; /* good */ 152 } else { 153 nd6log((LOG_INFO, "nd6_ns_input: bad DAD packet " 154 "(wrong ip6 dst)\n")); 155 goto bad; 156 } 157 } else if (!V_nd6_onlink_ns_rfc4861) { 158 struct sockaddr_in6 src_sa6; 159 160 /* 161 * According to recent IETF discussions, it is not a good idea 162 * to accept a NS from an address which would not be deemed 163 * to be a neighbor otherwise. This point is expected to be 164 * clarified in future revisions of the specification. 165 */ 166 bzero(&src_sa6, sizeof(src_sa6)); 167 src_sa6.sin6_family = AF_INET6; 168 src_sa6.sin6_len = sizeof(src_sa6); 169 src_sa6.sin6_addr = saddr6; 170 if (nd6_is_addr_neighbor(&src_sa6, ifp) == 0) { 171 nd6log((LOG_INFO, "nd6_ns_input: " 172 "NS packet from non-neighbor\n")); 173 goto bad; 174 } 175 } 176 177 if (IN6_IS_ADDR_MULTICAST(&taddr6)) { 178 nd6log((LOG_INFO, "nd6_ns_input: bad NS target (multicast)\n")); 179 goto bad; 180 } 181 182 icmp6len -= sizeof(*nd_ns); 183 nd6_option_init(nd_ns + 1, icmp6len, &ndopts); 184 if (nd6_options(&ndopts) < 0) { 185 nd6log((LOG_INFO, 186 "nd6_ns_input: invalid ND option, ignored\n")); 187 /* nd6_options have incremented stats */ 188 goto freeit; 189 } 190 191 if (ndopts.nd_opts_src_lladdr) { 192 lladdr = (char *)(ndopts.nd_opts_src_lladdr + 1); 193 lladdrlen = ndopts.nd_opts_src_lladdr->nd_opt_len << 3; 194 } 195 196 if (IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_src) && lladdr) { 197 nd6log((LOG_INFO, "nd6_ns_input: bad DAD packet " 198 "(link-layer address option)\n")); 199 goto bad; 200 } 201 202 /* 203 * Attaching target link-layer address to the NA? 204 * (RFC 2461 7.2.4) 205 * 206 * NS IP dst is unicast/anycast MUST NOT add 207 * NS IP dst is solicited-node multicast MUST add 208 * 209 * In implementation, we add target link-layer address by default. 210 * We do not add one in MUST NOT cases. 211 */ 212 if (!IN6_IS_ADDR_MULTICAST(&daddr6)) 213 tlladdr = 0; 214 else 215 tlladdr = 1; 216 217 /* 218 * Target address (taddr6) must be either: 219 * (1) Valid unicast/anycast address for my receiving interface, 220 * (2) Unicast address for which I'm offering proxy service, or 221 * (3) "tentative" address on which DAD is being performed. 222 */ 223 /* (1) and (3) check. */ 224 if (ifp->if_carp) 225 ifa = (*carp_iamatch6_p)(ifp, &taddr6); 226 if (ifa == NULL) 227 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &taddr6); 228 229 /* (2) check. */ 230 if (ifa == NULL) { 231 struct rtentry *rt; 232 struct sockaddr_in6 tsin6; 233 int need_proxy; 234 #ifdef RADIX_MPATH 235 struct route_in6 ro; 236 #endif 237 238 bzero(&tsin6, sizeof tsin6); 239 tsin6.sin6_len = sizeof(struct sockaddr_in6); 240 tsin6.sin6_family = AF_INET6; 241 tsin6.sin6_addr = taddr6; 242 243 #ifdef RADIX_MPATH 244 bzero(&ro, sizeof(ro)); 245 ro.ro_dst = tsin6; 246 rtalloc_mpath((struct route *)&ro, RTF_ANNOUNCE); 247 rt = ro.ro_rt; 248 #else 249 rt = rtalloc1((struct sockaddr *)&tsin6, 0, 0); 250 #endif 251 need_proxy = (rt && (rt->rt_flags & RTF_ANNOUNCE) != 0 && 252 rt->rt_gateway->sa_family == AF_LINK); 253 if (rt) 254 RTFREE_LOCKED(rt); 255 if (need_proxy) { 256 /* 257 * proxy NDP for single entry 258 */ 259 ifa = (struct ifaddr *)in6ifa_ifpforlinklocal(ifp, 260 IN6_IFF_NOTREADY|IN6_IFF_ANYCAST); 261 if (ifa) { 262 proxy = 1; 263 proxydl = SDL(rt->rt_gateway); 264 } 265 } 266 } 267 if (ifa == NULL) { 268 /* 269 * We've got an NS packet, and we don't have that adddress 270 * assigned for us. We MUST silently ignore it. 271 * See RFC2461 7.2.3. 272 */ 273 goto freeit; 274 } 275 myaddr6 = *IFA_IN6(ifa); 276 anycast = ((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_ANYCAST; 277 tentative = ((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_TENTATIVE; 278 if (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_DUPLICATED) 279 goto freeit; 280 281 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) { 282 nd6log((LOG_INFO, "nd6_ns_input: lladdrlen mismatch for %s " 283 "(if %d, NS packet %d)\n", 284 ip6_sprintf(ip6bufs, &taddr6), 285 ifp->if_addrlen, lladdrlen - 2)); 286 goto bad; 287 } 288 289 if (IN6_ARE_ADDR_EQUAL(&myaddr6, &saddr6)) { 290 nd6log((LOG_INFO, "nd6_ns_input: duplicate IP6 address %s\n", 291 ip6_sprintf(ip6bufs, &saddr6))); 292 goto freeit; 293 } 294 295 /* 296 * We have neighbor solicitation packet, with target address equals to 297 * one of my tentative address. 298 * 299 * src addr how to process? 300 * --- --- 301 * multicast of course, invalid (rejected in ip6_input) 302 * unicast somebody is doing address resolution -> ignore 303 * unspec dup address detection 304 * 305 * The processing is defined in RFC 2462. 306 */ 307 if (tentative) { 308 /* 309 * If source address is unspecified address, it is for 310 * duplicate address detection. 311 * 312 * If not, the packet is for addess resolution; 313 * silently ignore it. 314 */ 315 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) 316 nd6_dad_ns_input(ifa); 317 318 goto freeit; 319 } 320 321 /* 322 * If the source address is unspecified address, entries must not 323 * be created or updated. 324 * It looks that sender is performing DAD. Output NA toward 325 * all-node multicast address, to tell the sender that I'm using 326 * the address. 327 * S bit ("solicited") must be zero. 328 */ 329 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) { 330 struct in6_addr in6_all; 331 332 in6_all = in6addr_linklocal_allnodes; 333 if (in6_setscope(&in6_all, ifp, NULL) != 0) 334 goto bad; 335 nd6_na_output(ifp, &in6_all, &taddr6, 336 ((anycast || proxy || !tlladdr) ? 0 : ND_NA_FLAG_OVERRIDE) | 337 (V_ip6_forwarding ? ND_NA_FLAG_ROUTER : 0), 338 tlladdr, (struct sockaddr *)proxydl); 339 goto freeit; 340 } 341 342 nd6_cache_lladdr(ifp, &saddr6, lladdr, lladdrlen, 343 ND_NEIGHBOR_SOLICIT, 0); 344 345 nd6_na_output(ifp, &saddr6, &taddr6, 346 ((anycast || proxy || !tlladdr) ? 0 : ND_NA_FLAG_OVERRIDE) | 347 (V_ip6_forwarding ? ND_NA_FLAG_ROUTER : 0) | ND_NA_FLAG_SOLICITED, 348 tlladdr, (struct sockaddr *)proxydl); 349 freeit: 350 if (ifa != NULL) 351 ifa_free(ifa); 352 m_freem(m); 353 return; 354 355 bad: 356 nd6log((LOG_ERR, "nd6_ns_input: src=%s\n", 357 ip6_sprintf(ip6bufs, &saddr6))); 358 nd6log((LOG_ERR, "nd6_ns_input: dst=%s\n", 359 ip6_sprintf(ip6bufs, &daddr6))); 360 nd6log((LOG_ERR, "nd6_ns_input: tgt=%s\n", 361 ip6_sprintf(ip6bufs, &taddr6))); 362 ICMP6STAT_INC(icp6s_badns); 363 if (ifa != NULL) 364 ifa_free(ifa); 365 m_freem(m); 366 } 367 368 /* 369 * Output a Neighbor Solicitation Message. Caller specifies: 370 * - ICMP6 header source IP6 address 371 * - ND6 header target IP6 address 372 * - ND6 header source datalink address 373 * 374 * Based on RFC 2461 375 * Based on RFC 2462 (duplicate address detection) 376 * 377 * ln - for source address determination 378 * dad - duplicate address detection 379 */ 380 void 381 nd6_ns_output(struct ifnet *ifp, const struct in6_addr *daddr6, 382 const struct in6_addr *taddr6, struct llentry *ln, int dad) 383 { 384 struct mbuf *m; 385 struct ip6_hdr *ip6; 386 struct nd_neighbor_solicit *nd_ns; 387 struct in6_addr *src, src_in; 388 struct ip6_moptions im6o; 389 int icmp6len; 390 int maxlen; 391 caddr_t mac; 392 struct route_in6 ro; 393 394 bzero(&ro, sizeof(ro)); 395 396 if (IN6_IS_ADDR_MULTICAST(taddr6)) 397 return; 398 399 /* estimate the size of message */ 400 maxlen = sizeof(*ip6) + sizeof(*nd_ns); 401 maxlen += (sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7; 402 if (max_linkhdr + maxlen >= MCLBYTES) { 403 #ifdef DIAGNOSTIC 404 printf("nd6_ns_output: max_linkhdr + maxlen >= MCLBYTES " 405 "(%d + %d > %d)\n", max_linkhdr, maxlen, MCLBYTES); 406 #endif 407 return; 408 } 409 410 MGETHDR(m, M_DONTWAIT, MT_DATA); 411 if (m && max_linkhdr + maxlen >= MHLEN) { 412 MCLGET(m, M_DONTWAIT); 413 if ((m->m_flags & M_EXT) == 0) { 414 m_free(m); 415 m = NULL; 416 } 417 } 418 if (m == NULL) 419 return; 420 m->m_pkthdr.rcvif = NULL; 421 422 if (daddr6 == NULL || IN6_IS_ADDR_MULTICAST(daddr6)) { 423 m->m_flags |= M_MCAST; 424 im6o.im6o_multicast_ifp = ifp; 425 im6o.im6o_multicast_hlim = 255; 426 im6o.im6o_multicast_loop = 0; 427 } 428 429 icmp6len = sizeof(*nd_ns); 430 m->m_pkthdr.len = m->m_len = sizeof(*ip6) + icmp6len; 431 m->m_data += max_linkhdr; /* or MH_ALIGN() equivalent? */ 432 433 /* fill neighbor solicitation packet */ 434 ip6 = mtod(m, struct ip6_hdr *); 435 ip6->ip6_flow = 0; 436 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 437 ip6->ip6_vfc |= IPV6_VERSION; 438 /* ip6->ip6_plen will be set later */ 439 ip6->ip6_nxt = IPPROTO_ICMPV6; 440 ip6->ip6_hlim = 255; 441 if (daddr6) 442 ip6->ip6_dst = *daddr6; 443 else { 444 ip6->ip6_dst.s6_addr16[0] = IPV6_ADDR_INT16_MLL; 445 ip6->ip6_dst.s6_addr16[1] = 0; 446 ip6->ip6_dst.s6_addr32[1] = 0; 447 ip6->ip6_dst.s6_addr32[2] = IPV6_ADDR_INT32_ONE; 448 ip6->ip6_dst.s6_addr32[3] = taddr6->s6_addr32[3]; 449 ip6->ip6_dst.s6_addr8[12] = 0xff; 450 if (in6_setscope(&ip6->ip6_dst, ifp, NULL) != 0) 451 goto bad; 452 } 453 if (!dad) { 454 struct ifaddr *ifa; 455 456 /* 457 * RFC2461 7.2.2: 458 * "If the source address of the packet prompting the 459 * solicitation is the same as one of the addresses assigned 460 * to the outgoing interface, that address SHOULD be placed 461 * in the IP Source Address of the outgoing solicitation. 462 * Otherwise, any one of the addresses assigned to the 463 * interface should be used." 464 * 465 * We use the source address for the prompting packet 466 * (saddr6), if: 467 * - saddr6 is given from the caller (by giving "ln"), and 468 * - saddr6 belongs to the outgoing interface. 469 * Otherwise, we perform the source address selection as usual. 470 */ 471 struct ip6_hdr *hip6; /* hold ip6 */ 472 struct in6_addr *hsrc = NULL; 473 474 if ((ln != NULL) && ln->la_hold) { 475 /* 476 * assuming every packet in la_hold has the same IP 477 * header 478 */ 479 hip6 = mtod(ln->la_hold, struct ip6_hdr *); 480 /* XXX pullup? */ 481 if (sizeof(*hip6) < ln->la_hold->m_len) 482 hsrc = &hip6->ip6_src; 483 else 484 hsrc = NULL; 485 } 486 if (hsrc && (ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, 487 hsrc)) != NULL) { 488 src = hsrc; 489 ifa_free(ifa); 490 } else { 491 int error; 492 struct sockaddr_in6 dst_sa; 493 494 bzero(&dst_sa, sizeof(dst_sa)); 495 dst_sa.sin6_family = AF_INET6; 496 dst_sa.sin6_len = sizeof(dst_sa); 497 dst_sa.sin6_addr = ip6->ip6_dst; 498 499 error = in6_selectsrc(&dst_sa, NULL, 500 NULL, &ro, NULL, NULL, &src_in); 501 if (error) { 502 char ip6buf[INET6_ADDRSTRLEN]; 503 nd6log((LOG_DEBUG, 504 "nd6_ns_output: source can't be " 505 "determined: dst=%s, error=%d\n", 506 ip6_sprintf(ip6buf, &dst_sa.sin6_addr), 507 error)); 508 goto bad; 509 } 510 src = &src_in; 511 } 512 } else { 513 /* 514 * Source address for DAD packet must always be IPv6 515 * unspecified address. (0::0) 516 * We actually don't have to 0-clear the address (we did it 517 * above), but we do so here explicitly to make the intention 518 * clearer. 519 */ 520 bzero(&src_in, sizeof(src_in)); 521 src = &src_in; 522 } 523 ip6->ip6_src = *src; 524 nd_ns = (struct nd_neighbor_solicit *)(ip6 + 1); 525 nd_ns->nd_ns_type = ND_NEIGHBOR_SOLICIT; 526 nd_ns->nd_ns_code = 0; 527 nd_ns->nd_ns_reserved = 0; 528 nd_ns->nd_ns_target = *taddr6; 529 in6_clearscope(&nd_ns->nd_ns_target); /* XXX */ 530 531 /* 532 * Add source link-layer address option. 533 * 534 * spec implementation 535 * --- --- 536 * DAD packet MUST NOT do not add the option 537 * there's no link layer address: 538 * impossible do not add the option 539 * there's link layer address: 540 * Multicast NS MUST add one add the option 541 * Unicast NS SHOULD add one add the option 542 */ 543 if (!dad && (mac = nd6_ifptomac(ifp))) { 544 int optlen = sizeof(struct nd_opt_hdr) + ifp->if_addrlen; 545 struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)(nd_ns + 1); 546 /* 8 byte alignments... */ 547 optlen = (optlen + 7) & ~7; 548 549 m->m_pkthdr.len += optlen; 550 m->m_len += optlen; 551 icmp6len += optlen; 552 bzero((caddr_t)nd_opt, optlen); 553 nd_opt->nd_opt_type = ND_OPT_SOURCE_LINKADDR; 554 nd_opt->nd_opt_len = optlen >> 3; 555 bcopy(mac, (caddr_t)(nd_opt + 1), ifp->if_addrlen); 556 } 557 558 ip6->ip6_plen = htons((u_short)icmp6len); 559 nd_ns->nd_ns_cksum = 0; 560 nd_ns->nd_ns_cksum = 561 in6_cksum(m, IPPROTO_ICMPV6, sizeof(*ip6), icmp6len); 562 563 ip6_output(m, NULL, &ro, dad ? IPV6_UNSPECSRC : 0, &im6o, NULL, NULL); 564 icmp6_ifstat_inc(ifp, ifs6_out_msg); 565 icmp6_ifstat_inc(ifp, ifs6_out_neighborsolicit); 566 ICMP6STAT_INC(icp6s_outhist[ND_NEIGHBOR_SOLICIT]); 567 568 if (ro.ro_rt) { /* we don't cache this route. */ 569 RTFREE(ro.ro_rt); 570 } 571 return; 572 573 bad: 574 if (ro.ro_rt) { 575 RTFREE(ro.ro_rt); 576 } 577 m_freem(m); 578 return; 579 } 580 581 /* 582 * Neighbor advertisement input handling. 583 * 584 * Based on RFC 2461 585 * Based on RFC 2462 (duplicate address detection) 586 * 587 * the following items are not implemented yet: 588 * - proxy advertisement delay rule (RFC2461 7.2.8, last paragraph, SHOULD) 589 * - anycast advertisement delay rule (RFC2461 7.2.7, SHOULD) 590 */ 591 void 592 nd6_na_input(struct mbuf *m, int off, int icmp6len) 593 { 594 struct ifnet *ifp = m->m_pkthdr.rcvif; 595 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 596 struct nd_neighbor_advert *nd_na; 597 struct in6_addr daddr6 = ip6->ip6_dst; 598 struct in6_addr taddr6; 599 int flags; 600 int is_router; 601 int is_solicited; 602 int is_override; 603 char *lladdr = NULL; 604 int lladdrlen = 0; 605 int checklink = 0; 606 struct ifaddr *ifa; 607 struct llentry *ln = NULL; 608 union nd_opts ndopts; 609 struct mbuf *chain = NULL; 610 struct sockaddr_in6 sin6; 611 char ip6bufs[INET6_ADDRSTRLEN], ip6bufd[INET6_ADDRSTRLEN]; 612 613 if (ip6->ip6_hlim != 255) { 614 nd6log((LOG_ERR, 615 "nd6_na_input: invalid hlim (%d) from %s to %s on %s\n", 616 ip6->ip6_hlim, ip6_sprintf(ip6bufs, &ip6->ip6_src), 617 ip6_sprintf(ip6bufd, &ip6->ip6_dst), if_name(ifp))); 618 goto bad; 619 } 620 621 #ifndef PULLDOWN_TEST 622 IP6_EXTHDR_CHECK(m, off, icmp6len,); 623 nd_na = (struct nd_neighbor_advert *)((caddr_t)ip6 + off); 624 #else 625 IP6_EXTHDR_GET(nd_na, struct nd_neighbor_advert *, m, off, icmp6len); 626 if (nd_na == NULL) { 627 ICMP6STAT_INC(icp6s_tooshort); 628 return; 629 } 630 #endif 631 632 flags = nd_na->nd_na_flags_reserved; 633 is_router = ((flags & ND_NA_FLAG_ROUTER) != 0); 634 is_solicited = ((flags & ND_NA_FLAG_SOLICITED) != 0); 635 is_override = ((flags & ND_NA_FLAG_OVERRIDE) != 0); 636 637 taddr6 = nd_na->nd_na_target; 638 if (in6_setscope(&taddr6, ifp, NULL)) 639 goto bad; /* XXX: impossible */ 640 641 if (IN6_IS_ADDR_MULTICAST(&taddr6)) { 642 nd6log((LOG_ERR, 643 "nd6_na_input: invalid target address %s\n", 644 ip6_sprintf(ip6bufs, &taddr6))); 645 goto bad; 646 } 647 if (IN6_IS_ADDR_MULTICAST(&daddr6)) 648 if (is_solicited) { 649 nd6log((LOG_ERR, 650 "nd6_na_input: a solicited adv is multicasted\n")); 651 goto bad; 652 } 653 654 icmp6len -= sizeof(*nd_na); 655 nd6_option_init(nd_na + 1, icmp6len, &ndopts); 656 if (nd6_options(&ndopts) < 0) { 657 nd6log((LOG_INFO, 658 "nd6_na_input: invalid ND option, ignored\n")); 659 /* nd6_options have incremented stats */ 660 goto freeit; 661 } 662 663 if (ndopts.nd_opts_tgt_lladdr) { 664 lladdr = (char *)(ndopts.nd_opts_tgt_lladdr + 1); 665 lladdrlen = ndopts.nd_opts_tgt_lladdr->nd_opt_len << 3; 666 } 667 668 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &taddr6); 669 670 /* 671 * Target address matches one of my interface address. 672 * 673 * If my address is tentative, this means that there's somebody 674 * already using the same address as mine. This indicates DAD failure. 675 * This is defined in RFC 2462. 676 * 677 * Otherwise, process as defined in RFC 2461. 678 */ 679 if (ifa 680 && (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_TENTATIVE)) { 681 ifa_free(ifa); 682 nd6_dad_na_input(ifa); 683 goto freeit; 684 } 685 686 /* Just for safety, maybe unnecessary. */ 687 if (ifa) { 688 ifa_free(ifa); 689 log(LOG_ERR, 690 "nd6_na_input: duplicate IP6 address %s\n", 691 ip6_sprintf(ip6bufs, &taddr6)); 692 goto freeit; 693 } 694 695 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) { 696 nd6log((LOG_INFO, "nd6_na_input: lladdrlen mismatch for %s " 697 "(if %d, NA packet %d)\n", ip6_sprintf(ip6bufs, &taddr6), 698 ifp->if_addrlen, lladdrlen - 2)); 699 goto bad; 700 } 701 702 /* 703 * If no neighbor cache entry is found, NA SHOULD silently be 704 * discarded. 705 */ 706 IF_AFDATA_LOCK(ifp); 707 ln = nd6_lookup(&taddr6, LLE_EXCLUSIVE, ifp); 708 IF_AFDATA_UNLOCK(ifp); 709 if (ln == NULL) { 710 goto freeit; 711 } 712 713 if (ln->ln_state == ND6_LLINFO_INCOMPLETE) { 714 /* 715 * If the link-layer has address, and no lladdr option came, 716 * discard the packet. 717 */ 718 if (ifp->if_addrlen && lladdr == NULL) { 719 goto freeit; 720 } 721 722 /* 723 * Record link-layer address, and update the state. 724 */ 725 bcopy(lladdr, &ln->ll_addr, ifp->if_addrlen); 726 ln->la_flags |= LLE_VALID; 727 if (is_solicited) { 728 ln->ln_state = ND6_LLINFO_REACHABLE; 729 ln->ln_byhint = 0; 730 if (!ND6_LLINFO_PERMANENT(ln)) { 731 nd6_llinfo_settimer_locked(ln, 732 (long)ND_IFINFO(ln->lle_tbl->llt_ifp)->reachable * hz); 733 } 734 } else { 735 ln->ln_state = ND6_LLINFO_STALE; 736 nd6_llinfo_settimer_locked(ln, (long)V_nd6_gctimer * hz); 737 } 738 if ((ln->ln_router = is_router) != 0) { 739 /* 740 * This means a router's state has changed from 741 * non-reachable to probably reachable, and might 742 * affect the status of associated prefixes.. 743 */ 744 checklink = 1; 745 } 746 } else { 747 int llchange; 748 749 /* 750 * Check if the link-layer address has changed or not. 751 */ 752 if (lladdr == NULL) 753 llchange = 0; 754 else { 755 if (ln->la_flags & LLE_VALID) { 756 if (bcmp(lladdr, &ln->ll_addr, ifp->if_addrlen)) 757 llchange = 1; 758 else 759 llchange = 0; 760 } else 761 llchange = 1; 762 } 763 764 /* 765 * This is VERY complex. Look at it with care. 766 * 767 * override solicit lladdr llchange action 768 * (L: record lladdr) 769 * 770 * 0 0 n -- (2c) 771 * 0 0 y n (2b) L 772 * 0 0 y y (1) REACHABLE->STALE 773 * 0 1 n -- (2c) *->REACHABLE 774 * 0 1 y n (2b) L *->REACHABLE 775 * 0 1 y y (1) REACHABLE->STALE 776 * 1 0 n -- (2a) 777 * 1 0 y n (2a) L 778 * 1 0 y y (2a) L *->STALE 779 * 1 1 n -- (2a) *->REACHABLE 780 * 1 1 y n (2a) L *->REACHABLE 781 * 1 1 y y (2a) L *->REACHABLE 782 */ 783 if (!is_override && (lladdr != NULL && llchange)) { /* (1) */ 784 /* 785 * If state is REACHABLE, make it STALE. 786 * no other updates should be done. 787 */ 788 if (ln->ln_state == ND6_LLINFO_REACHABLE) { 789 ln->ln_state = ND6_LLINFO_STALE; 790 nd6_llinfo_settimer_locked(ln, (long)V_nd6_gctimer * hz); 791 } 792 goto freeit; 793 } else if (is_override /* (2a) */ 794 || (!is_override && (lladdr != NULL && !llchange)) /* (2b) */ 795 || lladdr == NULL) { /* (2c) */ 796 /* 797 * Update link-local address, if any. 798 */ 799 if (lladdr != NULL) { 800 bcopy(lladdr, &ln->ll_addr, ifp->if_addrlen); 801 ln->la_flags |= LLE_VALID; 802 } 803 804 /* 805 * If solicited, make the state REACHABLE. 806 * If not solicited and the link-layer address was 807 * changed, make it STALE. 808 */ 809 if (is_solicited) { 810 ln->ln_state = ND6_LLINFO_REACHABLE; 811 ln->ln_byhint = 0; 812 if (!ND6_LLINFO_PERMANENT(ln)) { 813 nd6_llinfo_settimer_locked(ln, 814 (long)ND_IFINFO(ifp)->reachable * hz); 815 } 816 } else { 817 if (lladdr != NULL && llchange) { 818 ln->ln_state = ND6_LLINFO_STALE; 819 nd6_llinfo_settimer_locked(ln, 820 (long)V_nd6_gctimer * hz); 821 } 822 } 823 } 824 825 if (ln->ln_router && !is_router) { 826 /* 827 * The peer dropped the router flag. 828 * Remove the sender from the Default Router List and 829 * update the Destination Cache entries. 830 */ 831 struct nd_defrouter *dr; 832 struct in6_addr *in6; 833 834 in6 = &L3_ADDR_SIN6(ln)->sin6_addr; 835 836 /* 837 * Lock to protect the default router list. 838 * XXX: this might be unnecessary, since this function 839 * is only called under the network software interrupt 840 * context. However, we keep it just for safety. 841 */ 842 dr = defrouter_lookup(in6, ln->lle_tbl->llt_ifp); 843 if (dr) 844 defrtrlist_del(dr); 845 else if (!V_ip6_forwarding) { 846 /* 847 * Even if the neighbor is not in the default 848 * router list, the neighbor may be used 849 * as a next hop for some destinations 850 * (e.g. redirect case). So we must 851 * call rt6_flush explicitly. 852 */ 853 rt6_flush(&ip6->ip6_src, ifp); 854 } 855 } 856 ln->ln_router = is_router; 857 } 858 /* XXX - QL 859 * Does this matter? 860 * rt->rt_flags &= ~RTF_REJECT; 861 */ 862 ln->la_asked = 0; 863 if (ln->la_hold) { 864 struct mbuf *m_hold, *m_hold_next; 865 866 /* 867 * reset the la_hold in advance, to explicitly 868 * prevent a la_hold lookup in nd6_output() 869 * (wouldn't happen, though...) 870 */ 871 for (m_hold = ln->la_hold, ln->la_hold = NULL; 872 m_hold; m_hold = m_hold_next) { 873 m_hold_next = m_hold->m_nextpkt; 874 m_hold->m_nextpkt = NULL; 875 /* 876 * we assume ifp is not a loopback here, so just set 877 * the 2nd argument as the 1st one. 878 */ 879 nd6_output_lle(ifp, ifp, m_hold, L3_ADDR_SIN6(ln), NULL, ln, &chain); 880 } 881 } 882 freeit: 883 if (ln != NULL) { 884 if (chain) 885 memcpy(&sin6, L3_ADDR_SIN6(ln), sizeof(sin6)); 886 LLE_WUNLOCK(ln); 887 888 if (chain) 889 nd6_output_flush(ifp, ifp, chain, &sin6, NULL); 890 } 891 if (checklink) 892 pfxlist_onlink_check(); 893 894 m_freem(m); 895 return; 896 897 bad: 898 if (ln != NULL) 899 LLE_WUNLOCK(ln); 900 901 ICMP6STAT_INC(icp6s_badna); 902 m_freem(m); 903 } 904 905 /* 906 * Neighbor advertisement output handling. 907 * 908 * Based on RFC 2461 909 * 910 * the following items are not implemented yet: 911 * - proxy advertisement delay rule (RFC2461 7.2.8, last paragraph, SHOULD) 912 * - anycast advertisement delay rule (RFC2461 7.2.7, SHOULD) 913 * 914 * tlladdr - 1 if include target link-layer address 915 * sdl0 - sockaddr_dl (= proxy NA) or NULL 916 */ 917 void 918 nd6_na_output(struct ifnet *ifp, const struct in6_addr *daddr6_0, 919 const struct in6_addr *taddr6, u_long flags, int tlladdr, 920 struct sockaddr *sdl0) 921 { 922 struct mbuf *m; 923 struct ip6_hdr *ip6; 924 struct nd_neighbor_advert *nd_na; 925 struct ip6_moptions im6o; 926 struct in6_addr src, daddr6; 927 struct sockaddr_in6 dst_sa; 928 int icmp6len, maxlen, error; 929 caddr_t mac = NULL; 930 struct route_in6 ro; 931 932 bzero(&ro, sizeof(ro)); 933 934 daddr6 = *daddr6_0; /* make a local copy for modification */ 935 936 /* estimate the size of message */ 937 maxlen = sizeof(*ip6) + sizeof(*nd_na); 938 maxlen += (sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7; 939 if (max_linkhdr + maxlen >= MCLBYTES) { 940 #ifdef DIAGNOSTIC 941 printf("nd6_na_output: max_linkhdr + maxlen >= MCLBYTES " 942 "(%d + %d > %d)\n", max_linkhdr, maxlen, MCLBYTES); 943 #endif 944 return; 945 } 946 947 MGETHDR(m, M_DONTWAIT, MT_DATA); 948 if (m && max_linkhdr + maxlen >= MHLEN) { 949 MCLGET(m, M_DONTWAIT); 950 if ((m->m_flags & M_EXT) == 0) { 951 m_free(m); 952 m = NULL; 953 } 954 } 955 if (m == NULL) 956 return; 957 m->m_pkthdr.rcvif = NULL; 958 959 if (IN6_IS_ADDR_MULTICAST(&daddr6)) { 960 m->m_flags |= M_MCAST; 961 im6o.im6o_multicast_ifp = ifp; 962 im6o.im6o_multicast_hlim = 255; 963 im6o.im6o_multicast_loop = 0; 964 } 965 966 icmp6len = sizeof(*nd_na); 967 m->m_pkthdr.len = m->m_len = sizeof(struct ip6_hdr) + icmp6len; 968 m->m_data += max_linkhdr; /* or MH_ALIGN() equivalent? */ 969 970 /* fill neighbor advertisement packet */ 971 ip6 = mtod(m, struct ip6_hdr *); 972 ip6->ip6_flow = 0; 973 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 974 ip6->ip6_vfc |= IPV6_VERSION; 975 ip6->ip6_nxt = IPPROTO_ICMPV6; 976 ip6->ip6_hlim = 255; 977 if (IN6_IS_ADDR_UNSPECIFIED(&daddr6)) { 978 /* reply to DAD */ 979 daddr6.s6_addr16[0] = IPV6_ADDR_INT16_MLL; 980 daddr6.s6_addr16[1] = 0; 981 daddr6.s6_addr32[1] = 0; 982 daddr6.s6_addr32[2] = 0; 983 daddr6.s6_addr32[3] = IPV6_ADDR_INT32_ONE; 984 if (in6_setscope(&daddr6, ifp, NULL)) 985 goto bad; 986 987 flags &= ~ND_NA_FLAG_SOLICITED; 988 } 989 ip6->ip6_dst = daddr6; 990 bzero(&dst_sa, sizeof(struct sockaddr_in6)); 991 dst_sa.sin6_family = AF_INET6; 992 dst_sa.sin6_len = sizeof(struct sockaddr_in6); 993 dst_sa.sin6_addr = daddr6; 994 995 /* 996 * Select a source whose scope is the same as that of the dest. 997 */ 998 bcopy(&dst_sa, &ro.ro_dst, sizeof(dst_sa)); 999 error = in6_selectsrc(&dst_sa, NULL, NULL, &ro, NULL, NULL, &src); 1000 if (error) { 1001 char ip6buf[INET6_ADDRSTRLEN]; 1002 nd6log((LOG_DEBUG, "nd6_na_output: source can't be " 1003 "determined: dst=%s, error=%d\n", 1004 ip6_sprintf(ip6buf, &dst_sa.sin6_addr), error)); 1005 goto bad; 1006 } 1007 ip6->ip6_src = src; 1008 nd_na = (struct nd_neighbor_advert *)(ip6 + 1); 1009 nd_na->nd_na_type = ND_NEIGHBOR_ADVERT; 1010 nd_na->nd_na_code = 0; 1011 nd_na->nd_na_target = *taddr6; 1012 in6_clearscope(&nd_na->nd_na_target); /* XXX */ 1013 1014 /* 1015 * "tlladdr" indicates NS's condition for adding tlladdr or not. 1016 * see nd6_ns_input() for details. 1017 * Basically, if NS packet is sent to unicast/anycast addr, 1018 * target lladdr option SHOULD NOT be included. 1019 */ 1020 if (tlladdr) { 1021 /* 1022 * sdl0 != NULL indicates proxy NA. If we do proxy, use 1023 * lladdr in sdl0. If we are not proxying (sending NA for 1024 * my address) use lladdr configured for the interface. 1025 */ 1026 if (sdl0 == NULL) { 1027 if (ifp->if_carp) 1028 mac = (*carp_macmatch6_p)(ifp, m, taddr6); 1029 if (mac == NULL) 1030 mac = nd6_ifptomac(ifp); 1031 } else if (sdl0->sa_family == AF_LINK) { 1032 struct sockaddr_dl *sdl; 1033 sdl = (struct sockaddr_dl *)sdl0; 1034 if (sdl->sdl_alen == ifp->if_addrlen) 1035 mac = LLADDR(sdl); 1036 } 1037 } 1038 if (tlladdr && mac) { 1039 int optlen = sizeof(struct nd_opt_hdr) + ifp->if_addrlen; 1040 struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)(nd_na + 1); 1041 1042 /* roundup to 8 bytes alignment! */ 1043 optlen = (optlen + 7) & ~7; 1044 1045 m->m_pkthdr.len += optlen; 1046 m->m_len += optlen; 1047 icmp6len += optlen; 1048 bzero((caddr_t)nd_opt, optlen); 1049 nd_opt->nd_opt_type = ND_OPT_TARGET_LINKADDR; 1050 nd_opt->nd_opt_len = optlen >> 3; 1051 bcopy(mac, (caddr_t)(nd_opt + 1), ifp->if_addrlen); 1052 } else 1053 flags &= ~ND_NA_FLAG_OVERRIDE; 1054 1055 ip6->ip6_plen = htons((u_short)icmp6len); 1056 nd_na->nd_na_flags_reserved = flags; 1057 nd_na->nd_na_cksum = 0; 1058 nd_na->nd_na_cksum = 1059 in6_cksum(m, IPPROTO_ICMPV6, sizeof(struct ip6_hdr), icmp6len); 1060 1061 ip6_output(m, NULL, &ro, 0, &im6o, NULL, NULL); 1062 icmp6_ifstat_inc(ifp, ifs6_out_msg); 1063 icmp6_ifstat_inc(ifp, ifs6_out_neighboradvert); 1064 ICMP6STAT_INC(icp6s_outhist[ND_NEIGHBOR_ADVERT]); 1065 1066 if (ro.ro_rt) { /* we don't cache this route. */ 1067 RTFREE(ro.ro_rt); 1068 } 1069 return; 1070 1071 bad: 1072 if (ro.ro_rt) { 1073 RTFREE(ro.ro_rt); 1074 } 1075 m_freem(m); 1076 return; 1077 } 1078 1079 caddr_t 1080 nd6_ifptomac(struct ifnet *ifp) 1081 { 1082 switch (ifp->if_type) { 1083 case IFT_ARCNET: 1084 case IFT_ETHER: 1085 case IFT_FDDI: 1086 case IFT_IEEE1394: 1087 #ifdef IFT_L2VLAN 1088 case IFT_L2VLAN: 1089 #endif 1090 #ifdef IFT_IEEE80211 1091 case IFT_IEEE80211: 1092 #endif 1093 #ifdef IFT_CARP 1094 case IFT_CARP: 1095 #endif 1096 case IFT_BRIDGE: 1097 case IFT_ISO88025: 1098 return IF_LLADDR(ifp); 1099 default: 1100 return NULL; 1101 } 1102 } 1103 1104 struct dadq { 1105 TAILQ_ENTRY(dadq) dad_list; 1106 struct ifaddr *dad_ifa; 1107 int dad_count; /* max NS to send */ 1108 int dad_ns_tcount; /* # of trials to send NS */ 1109 int dad_ns_ocount; /* NS sent so far */ 1110 int dad_ns_icount; 1111 int dad_na_icount; 1112 struct callout dad_timer_ch; 1113 struct vnet *dad_vnet; 1114 }; 1115 1116 static VNET_DEFINE(TAILQ_HEAD(, dadq), dadq); 1117 VNET_DEFINE(int, dad_init) = 0; 1118 #define V_dadq VNET(dadq) 1119 #define V_dad_init VNET(dad_init) 1120 1121 static struct dadq * 1122 nd6_dad_find(struct ifaddr *ifa) 1123 { 1124 struct dadq *dp; 1125 1126 for (dp = V_dadq.tqh_first; dp; dp = dp->dad_list.tqe_next) { 1127 if (dp->dad_ifa == ifa) 1128 return dp; 1129 } 1130 return NULL; 1131 } 1132 1133 static void 1134 nd6_dad_starttimer(struct dadq *dp, int ticks) 1135 { 1136 1137 callout_reset(&dp->dad_timer_ch, ticks, 1138 (void (*)(void *))nd6_dad_timer, (void *)dp); 1139 } 1140 1141 static void 1142 nd6_dad_stoptimer(struct dadq *dp) 1143 { 1144 1145 callout_stop(&dp->dad_timer_ch); 1146 } 1147 1148 /* 1149 * Start Duplicate Address Detection (DAD) for specified interface address. 1150 */ 1151 void 1152 nd6_dad_start(struct ifaddr *ifa, int delay) 1153 { 1154 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1155 struct dadq *dp; 1156 char ip6buf[INET6_ADDRSTRLEN]; 1157 1158 if (!V_dad_init) { 1159 TAILQ_INIT(&V_dadq); 1160 V_dad_init++; 1161 } 1162 1163 /* 1164 * If we don't need DAD, don't do it. 1165 * There are several cases: 1166 * - DAD is disabled (ip6_dad_count == 0) 1167 * - the interface address is anycast 1168 */ 1169 if (!(ia->ia6_flags & IN6_IFF_TENTATIVE)) { 1170 log(LOG_DEBUG, 1171 "nd6_dad_start: called with non-tentative address " 1172 "%s(%s)\n", 1173 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr), 1174 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1175 return; 1176 } 1177 if (ia->ia6_flags & IN6_IFF_ANYCAST) { 1178 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1179 return; 1180 } 1181 if (!V_ip6_dad_count) { 1182 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1183 return; 1184 } 1185 if (ifa->ifa_ifp == NULL) 1186 panic("nd6_dad_start: ifa->ifa_ifp == NULL"); 1187 if (!(ifa->ifa_ifp->if_flags & IFF_UP)) { 1188 return; 1189 } 1190 if (ND_IFINFO(ifa->ifa_ifp)->flags & ND6_IFF_IFDISABLED) 1191 return; 1192 if (nd6_dad_find(ifa) != NULL) { 1193 /* DAD already in progress */ 1194 return; 1195 } 1196 1197 dp = malloc(sizeof(*dp), M_IP6NDP, M_NOWAIT); 1198 if (dp == NULL) { 1199 log(LOG_ERR, "nd6_dad_start: memory allocation failed for " 1200 "%s(%s)\n", 1201 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr), 1202 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1203 return; 1204 } 1205 bzero(dp, sizeof(*dp)); 1206 callout_init(&dp->dad_timer_ch, 0); 1207 #ifdef VIMAGE 1208 dp->dad_vnet = curvnet; 1209 #endif 1210 TAILQ_INSERT_TAIL(&V_dadq, (struct dadq *)dp, dad_list); 1211 1212 nd6log((LOG_DEBUG, "%s: starting DAD for %s\n", if_name(ifa->ifa_ifp), 1213 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr))); 1214 1215 /* 1216 * Send NS packet for DAD, ip6_dad_count times. 1217 * Note that we must delay the first transmission, if this is the 1218 * first packet to be sent from the interface after interface 1219 * (re)initialization. 1220 */ 1221 dp->dad_ifa = ifa; 1222 ifa_ref(ifa); /* just for safety */ 1223 dp->dad_count = V_ip6_dad_count; 1224 dp->dad_ns_icount = dp->dad_na_icount = 0; 1225 dp->dad_ns_ocount = dp->dad_ns_tcount = 0; 1226 if (delay == 0) { 1227 nd6_dad_ns_output(dp, ifa); 1228 nd6_dad_starttimer(dp, 1229 (long)ND_IFINFO(ifa->ifa_ifp)->retrans * hz / 1000); 1230 } else { 1231 nd6_dad_starttimer(dp, delay); 1232 } 1233 } 1234 1235 /* 1236 * terminate DAD unconditionally. used for address removals. 1237 */ 1238 void 1239 nd6_dad_stop(struct ifaddr *ifa) 1240 { 1241 struct dadq *dp; 1242 1243 if (!V_dad_init) 1244 return; 1245 dp = nd6_dad_find(ifa); 1246 if (!dp) { 1247 /* DAD wasn't started yet */ 1248 return; 1249 } 1250 1251 nd6_dad_stoptimer(dp); 1252 1253 TAILQ_REMOVE(&V_dadq, (struct dadq *)dp, dad_list); 1254 free(dp, M_IP6NDP); 1255 dp = NULL; 1256 ifa_free(ifa); 1257 } 1258 1259 static void 1260 nd6_dad_timer(struct dadq *dp) 1261 { 1262 CURVNET_SET(dp->dad_vnet); 1263 int s; 1264 struct ifaddr *ifa = dp->dad_ifa; 1265 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1266 char ip6buf[INET6_ADDRSTRLEN]; 1267 1268 s = splnet(); /* XXX */ 1269 1270 /* Sanity check */ 1271 if (ia == NULL) { 1272 log(LOG_ERR, "nd6_dad_timer: called with null parameter\n"); 1273 goto done; 1274 } 1275 if (ia->ia6_flags & IN6_IFF_DUPLICATED) { 1276 log(LOG_ERR, "nd6_dad_timer: called with duplicated address " 1277 "%s(%s)\n", 1278 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr), 1279 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1280 goto done; 1281 } 1282 if ((ia->ia6_flags & IN6_IFF_TENTATIVE) == 0) { 1283 log(LOG_ERR, "nd6_dad_timer: called with non-tentative address " 1284 "%s(%s)\n", 1285 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr), 1286 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1287 goto done; 1288 } 1289 1290 /* timeouted with IFF_{RUNNING,UP} check */ 1291 if (dp->dad_ns_tcount > V_dad_maxtry) { 1292 nd6log((LOG_INFO, "%s: could not run DAD, driver problem?\n", 1293 if_name(ifa->ifa_ifp))); 1294 1295 TAILQ_REMOVE(&V_dadq, (struct dadq *)dp, dad_list); 1296 free(dp, M_IP6NDP); 1297 dp = NULL; 1298 ifa_free(ifa); 1299 goto done; 1300 } 1301 1302 /* Need more checks? */ 1303 if (dp->dad_ns_ocount < dp->dad_count) { 1304 /* 1305 * We have more NS to go. Send NS packet for DAD. 1306 */ 1307 nd6_dad_ns_output(dp, ifa); 1308 nd6_dad_starttimer(dp, 1309 (long)ND_IFINFO(ifa->ifa_ifp)->retrans * hz / 1000); 1310 } else { 1311 /* 1312 * We have transmitted sufficient number of DAD packets. 1313 * See what we've got. 1314 */ 1315 int duplicate; 1316 1317 duplicate = 0; 1318 1319 if (dp->dad_na_icount) { 1320 /* 1321 * the check is in nd6_dad_na_input(), 1322 * but just in case 1323 */ 1324 duplicate++; 1325 } 1326 1327 if (dp->dad_ns_icount) { 1328 /* We've seen NS, means DAD has failed. */ 1329 duplicate++; 1330 } 1331 1332 if (duplicate) { 1333 /* (*dp) will be freed in nd6_dad_duplicated() */ 1334 dp = NULL; 1335 nd6_dad_duplicated(ifa); 1336 } else { 1337 /* 1338 * We are done with DAD. No NA came, no NS came. 1339 * No duplicate address found. 1340 */ 1341 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1342 1343 nd6log((LOG_DEBUG, 1344 "%s: DAD complete for %s - no duplicates found\n", 1345 if_name(ifa->ifa_ifp), 1346 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr))); 1347 1348 TAILQ_REMOVE(&V_dadq, (struct dadq *)dp, dad_list); 1349 free(dp, M_IP6NDP); 1350 dp = NULL; 1351 ifa_free(ifa); 1352 } 1353 } 1354 1355 done: 1356 splx(s); 1357 CURVNET_RESTORE(); 1358 } 1359 1360 void 1361 nd6_dad_duplicated(struct ifaddr *ifa) 1362 { 1363 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1364 struct ifnet *ifp; 1365 struct dadq *dp; 1366 char ip6buf[INET6_ADDRSTRLEN]; 1367 1368 dp = nd6_dad_find(ifa); 1369 if (dp == NULL) { 1370 log(LOG_ERR, "nd6_dad_duplicated: DAD structure not found\n"); 1371 return; 1372 } 1373 1374 log(LOG_ERR, "%s: DAD detected duplicate IPv6 address %s: " 1375 "NS in/out=%d/%d, NA in=%d\n", 1376 if_name(ifa->ifa_ifp), ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr), 1377 dp->dad_ns_icount, dp->dad_ns_ocount, dp->dad_na_icount); 1378 1379 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1380 ia->ia6_flags |= IN6_IFF_DUPLICATED; 1381 1382 /* We are done with DAD, with duplicate address found. (failure) */ 1383 nd6_dad_stoptimer(dp); 1384 1385 ifp = ifa->ifa_ifp; 1386 log(LOG_ERR, "%s: DAD complete for %s - duplicate found\n", 1387 if_name(ifp), ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr)); 1388 log(LOG_ERR, "%s: manual intervention required\n", 1389 if_name(ifp)); 1390 1391 /* 1392 * If the address is a link-local address formed from an interface 1393 * identifier based on the hardware address which is supposed to be 1394 * uniquely assigned (e.g., EUI-64 for an Ethernet interface), IP 1395 * operation on the interface SHOULD be disabled. 1396 * [RFC 4862, Section 5.4.5] 1397 */ 1398 if (IN6_IS_ADDR_LINKLOCAL(&ia->ia_addr.sin6_addr)) { 1399 struct in6_addr in6; 1400 1401 /* 1402 * To avoid over-reaction, we only apply this logic when we are 1403 * very sure that hardware addresses are supposed to be unique. 1404 */ 1405 switch (ifp->if_type) { 1406 case IFT_ETHER: 1407 case IFT_FDDI: 1408 case IFT_ATM: 1409 case IFT_IEEE1394: 1410 #ifdef IFT_IEEE80211 1411 case IFT_IEEE80211: 1412 #endif 1413 in6 = ia->ia_addr.sin6_addr; 1414 if (in6_get_hw_ifid(ifp, &in6) == 0 && 1415 IN6_ARE_ADDR_EQUAL(&ia->ia_addr.sin6_addr, &in6)) { 1416 ND_IFINFO(ifp)->flags |= ND6_IFF_IFDISABLED; 1417 log(LOG_ERR, "%s: possible hardware address " 1418 "duplication detected, disable IPv6\n", 1419 if_name(ifp)); 1420 } 1421 break; 1422 } 1423 } 1424 1425 TAILQ_REMOVE(&V_dadq, (struct dadq *)dp, dad_list); 1426 free(dp, M_IP6NDP); 1427 dp = NULL; 1428 ifa_free(ifa); 1429 } 1430 1431 static void 1432 nd6_dad_ns_output(struct dadq *dp, struct ifaddr *ifa) 1433 { 1434 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1435 struct ifnet *ifp = ifa->ifa_ifp; 1436 1437 dp->dad_ns_tcount++; 1438 if ((ifp->if_flags & IFF_UP) == 0) { 1439 return; 1440 } 1441 if ((ifp->if_drv_flags & IFF_DRV_RUNNING) == 0) { 1442 return; 1443 } 1444 1445 dp->dad_ns_ocount++; 1446 nd6_ns_output(ifp, NULL, &ia->ia_addr.sin6_addr, NULL, 1); 1447 } 1448 1449 static void 1450 nd6_dad_ns_input(struct ifaddr *ifa) 1451 { 1452 struct in6_ifaddr *ia; 1453 struct ifnet *ifp; 1454 const struct in6_addr *taddr6; 1455 struct dadq *dp; 1456 int duplicate; 1457 1458 if (ifa == NULL) 1459 panic("ifa == NULL in nd6_dad_ns_input"); 1460 1461 ia = (struct in6_ifaddr *)ifa; 1462 ifp = ifa->ifa_ifp; 1463 taddr6 = &ia->ia_addr.sin6_addr; 1464 duplicate = 0; 1465 dp = nd6_dad_find(ifa); 1466 1467 /* Quickhack - completely ignore DAD NS packets */ 1468 if (V_dad_ignore_ns) { 1469 char ip6buf[INET6_ADDRSTRLEN]; 1470 nd6log((LOG_INFO, 1471 "nd6_dad_ns_input: ignoring DAD NS packet for " 1472 "address %s(%s)\n", ip6_sprintf(ip6buf, taddr6), 1473 if_name(ifa->ifa_ifp))); 1474 return; 1475 } 1476 1477 /* 1478 * if I'm yet to start DAD, someone else started using this address 1479 * first. I have a duplicate and you win. 1480 */ 1481 if (dp == NULL || dp->dad_ns_ocount == 0) 1482 duplicate++; 1483 1484 /* XXX more checks for loopback situation - see nd6_dad_timer too */ 1485 1486 if (duplicate) { 1487 dp = NULL; /* will be freed in nd6_dad_duplicated() */ 1488 nd6_dad_duplicated(ifa); 1489 } else { 1490 /* 1491 * not sure if I got a duplicate. 1492 * increment ns count and see what happens. 1493 */ 1494 if (dp) 1495 dp->dad_ns_icount++; 1496 } 1497 } 1498 1499 static void 1500 nd6_dad_na_input(struct ifaddr *ifa) 1501 { 1502 struct dadq *dp; 1503 1504 if (ifa == NULL) 1505 panic("ifa == NULL in nd6_dad_na_input"); 1506 1507 dp = nd6_dad_find(ifa); 1508 if (dp) 1509 dp->dad_na_icount++; 1510 1511 /* remove the address. */ 1512 nd6_dad_duplicated(ifa); 1513 } 1514