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 #include <netinet/ip_carp.h> 76 #include <netinet6/send.h> 77 78 #define SDL(s) ((struct sockaddr_dl *)s) 79 80 struct dadq; 81 static struct dadq *nd6_dad_find(struct ifaddr *); 82 static void nd6_dad_starttimer(struct dadq *, int); 83 static void nd6_dad_stoptimer(struct dadq *); 84 static void nd6_dad_timer(struct dadq *); 85 static void nd6_dad_ns_output(struct dadq *, struct ifaddr *); 86 static void nd6_dad_ns_input(struct ifaddr *); 87 static void nd6_dad_na_input(struct ifaddr *); 88 89 VNET_DEFINE(int, dad_ignore_ns) = 0; /* ignore NS in DAD - specwise incorrect*/ 90 VNET_DEFINE(int, dad_maxtry) = 15; /* max # of *tries* to transmit DAD packet */ 91 #define V_dad_ignore_ns VNET(dad_ignore_ns) 92 #define V_dad_maxtry VNET(dad_maxtry) 93 94 /* 95 * Input a Neighbor Solicitation Message. 96 * 97 * Based on RFC 2461 98 * Based on RFC 2462 (duplicate address detection) 99 */ 100 void 101 nd6_ns_input(struct mbuf *m, int off, int icmp6len) 102 { 103 struct ifnet *ifp = m->m_pkthdr.rcvif; 104 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 105 struct nd_neighbor_solicit *nd_ns; 106 struct in6_addr saddr6 = ip6->ip6_src; 107 struct in6_addr daddr6 = ip6->ip6_dst; 108 struct in6_addr taddr6; 109 struct in6_addr myaddr6; 110 char *lladdr = NULL; 111 struct ifaddr *ifa = NULL; 112 int lladdrlen = 0; 113 int anycast = 0, proxy = 0, tentative = 0; 114 int tlladdr; 115 union nd_opts ndopts; 116 struct sockaddr_dl *proxydl = NULL; 117 char ip6bufs[INET6_ADDRSTRLEN], ip6bufd[INET6_ADDRSTRLEN]; 118 119 #ifndef PULLDOWN_TEST 120 IP6_EXTHDR_CHECK(m, off, icmp6len,); 121 nd_ns = (struct nd_neighbor_solicit *)((caddr_t)ip6 + off); 122 #else 123 IP6_EXTHDR_GET(nd_ns, struct nd_neighbor_solicit *, m, off, icmp6len); 124 if (nd_ns == NULL) { 125 ICMP6STAT_INC(icp6s_tooshort); 126 return; 127 } 128 #endif 129 ip6 = mtod(m, struct ip6_hdr *); /* adjust pointer for safety */ 130 taddr6 = nd_ns->nd_ns_target; 131 if (in6_setscope(&taddr6, ifp, NULL) != 0) 132 goto bad; 133 134 if (ip6->ip6_hlim != 255) { 135 nd6log((LOG_ERR, 136 "nd6_ns_input: invalid hlim (%d) from %s to %s on %s\n", 137 ip6->ip6_hlim, ip6_sprintf(ip6bufs, &ip6->ip6_src), 138 ip6_sprintf(ip6bufd, &ip6->ip6_dst), if_name(ifp))); 139 goto bad; 140 } 141 142 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) { 143 /* dst has to be a solicited node multicast address. */ 144 if (daddr6.s6_addr16[0] == IPV6_ADDR_INT16_MLL && 145 /* don't check ifindex portion */ 146 daddr6.s6_addr32[1] == 0 && 147 daddr6.s6_addr32[2] == IPV6_ADDR_INT32_ONE && 148 daddr6.s6_addr8[12] == 0xff) { 149 ; /* good */ 150 } else { 151 nd6log((LOG_INFO, "nd6_ns_input: bad DAD packet " 152 "(wrong ip6 dst)\n")); 153 goto bad; 154 } 155 } else if (!V_nd6_onlink_ns_rfc4861) { 156 struct sockaddr_in6 src_sa6; 157 158 /* 159 * According to recent IETF discussions, it is not a good idea 160 * to accept a NS from an address which would not be deemed 161 * to be a neighbor otherwise. This point is expected to be 162 * clarified in future revisions of the specification. 163 */ 164 bzero(&src_sa6, sizeof(src_sa6)); 165 src_sa6.sin6_family = AF_INET6; 166 src_sa6.sin6_len = sizeof(src_sa6); 167 src_sa6.sin6_addr = saddr6; 168 if (nd6_is_addr_neighbor(&src_sa6, ifp) == 0) { 169 nd6log((LOG_INFO, "nd6_ns_input: " 170 "NS packet from non-neighbor\n")); 171 goto bad; 172 } 173 } 174 175 if (IN6_IS_ADDR_MULTICAST(&taddr6)) { 176 nd6log((LOG_INFO, "nd6_ns_input: bad NS target (multicast)\n")); 177 goto bad; 178 } 179 180 icmp6len -= sizeof(*nd_ns); 181 nd6_option_init(nd_ns + 1, icmp6len, &ndopts); 182 if (nd6_options(&ndopts) < 0) { 183 nd6log((LOG_INFO, 184 "nd6_ns_input: invalid ND option, ignored\n")); 185 /* nd6_options have incremented stats */ 186 goto freeit; 187 } 188 189 if (ndopts.nd_opts_src_lladdr) { 190 lladdr = (char *)(ndopts.nd_opts_src_lladdr + 1); 191 lladdrlen = ndopts.nd_opts_src_lladdr->nd_opt_len << 3; 192 } 193 194 if (IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_src) && lladdr) { 195 nd6log((LOG_INFO, "nd6_ns_input: bad DAD packet " 196 "(link-layer address option)\n")); 197 goto bad; 198 } 199 200 /* 201 * Attaching target link-layer address to the NA? 202 * (RFC 2461 7.2.4) 203 * 204 * NS IP dst is unicast/anycast MUST NOT add 205 * NS IP dst is solicited-node multicast MUST add 206 * 207 * In implementation, we add target link-layer address by default. 208 * We do not add one in MUST NOT cases. 209 */ 210 if (!IN6_IS_ADDR_MULTICAST(&daddr6)) 211 tlladdr = 0; 212 else 213 tlladdr = 1; 214 215 /* 216 * Target address (taddr6) must be either: 217 * (1) Valid unicast/anycast address for my receiving interface, 218 * (2) Unicast address for which I'm offering proxy service, or 219 * (3) "tentative" address on which DAD is being performed. 220 */ 221 /* (1) and (3) check. */ 222 if (ifp->if_carp) 223 ifa = (*carp_iamatch6_p)(ifp, &taddr6); 224 if (ifa == NULL) 225 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &taddr6); 226 227 /* (2) check. */ 228 if (ifa == NULL) { 229 struct rtentry *rt; 230 struct sockaddr_in6 tsin6; 231 int need_proxy; 232 #ifdef RADIX_MPATH 233 struct route_in6 ro; 234 #endif 235 236 bzero(&tsin6, sizeof tsin6); 237 tsin6.sin6_len = sizeof(struct sockaddr_in6); 238 tsin6.sin6_family = AF_INET6; 239 tsin6.sin6_addr = taddr6; 240 241 #ifdef RADIX_MPATH 242 bzero(&ro, sizeof(ro)); 243 ro.ro_dst = tsin6; 244 rtalloc_mpath((struct route *)&ro, RTF_ANNOUNCE); 245 rt = ro.ro_rt; 246 #else 247 rt = rtalloc1((struct sockaddr *)&tsin6, 0, 0); 248 #endif 249 need_proxy = (rt && (rt->rt_flags & RTF_ANNOUNCE) != 0 && 250 rt->rt_gateway->sa_family == AF_LINK); 251 if (rt) 252 RTFREE_LOCKED(rt); 253 if (need_proxy) { 254 /* 255 * proxy NDP for single entry 256 */ 257 ifa = (struct ifaddr *)in6ifa_ifpforlinklocal(ifp, 258 IN6_IFF_NOTREADY|IN6_IFF_ANYCAST); 259 if (ifa) { 260 proxy = 1; 261 proxydl = SDL(rt->rt_gateway); 262 } 263 } 264 } 265 if (ifa == NULL) { 266 /* 267 * We've got an NS packet, and we don't have that adddress 268 * assigned for us. We MUST silently ignore it. 269 * See RFC2461 7.2.3. 270 */ 271 goto freeit; 272 } 273 myaddr6 = *IFA_IN6(ifa); 274 anycast = ((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_ANYCAST; 275 tentative = ((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_TENTATIVE; 276 if (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_DUPLICATED) 277 goto freeit; 278 279 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) { 280 nd6log((LOG_INFO, "nd6_ns_input: lladdrlen mismatch for %s " 281 "(if %d, NS packet %d)\n", 282 ip6_sprintf(ip6bufs, &taddr6), 283 ifp->if_addrlen, lladdrlen - 2)); 284 goto bad; 285 } 286 287 if (IN6_ARE_ADDR_EQUAL(&myaddr6, &saddr6)) { 288 nd6log((LOG_INFO, "nd6_ns_input: duplicate IP6 address %s\n", 289 ip6_sprintf(ip6bufs, &saddr6))); 290 goto freeit; 291 } 292 293 /* 294 * We have neighbor solicitation packet, with target address equals to 295 * one of my tentative address. 296 * 297 * src addr how to process? 298 * --- --- 299 * multicast of course, invalid (rejected in ip6_input) 300 * unicast somebody is doing address resolution -> ignore 301 * unspec dup address detection 302 * 303 * The processing is defined in RFC 2462. 304 */ 305 if (tentative) { 306 /* 307 * If source address is unspecified address, it is for 308 * duplicate address detection. 309 * 310 * If not, the packet is for addess resolution; 311 * silently ignore it. 312 */ 313 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) 314 nd6_dad_ns_input(ifa); 315 316 goto freeit; 317 } 318 319 /* 320 * If the source address is unspecified address, entries must not 321 * be created or updated. 322 * It looks that sender is performing DAD. Output NA toward 323 * all-node multicast address, to tell the sender that I'm using 324 * the address. 325 * S bit ("solicited") must be zero. 326 */ 327 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) { 328 struct in6_addr in6_all; 329 330 in6_all = in6addr_linklocal_allnodes; 331 if (in6_setscope(&in6_all, ifp, NULL) != 0) 332 goto bad; 333 nd6_na_output(ifp, &in6_all, &taddr6, 334 ((anycast || proxy || !tlladdr) ? 0 : ND_NA_FLAG_OVERRIDE) | 335 (V_ip6_forwarding ? ND_NA_FLAG_ROUTER : 0), 336 tlladdr, (struct sockaddr *)proxydl); 337 goto freeit; 338 } 339 340 nd6_cache_lladdr(ifp, &saddr6, lladdr, lladdrlen, 341 ND_NEIGHBOR_SOLICIT, 0); 342 343 nd6_na_output(ifp, &saddr6, &taddr6, 344 ((anycast || proxy || !tlladdr) ? 0 : ND_NA_FLAG_OVERRIDE) | 345 (V_ip6_forwarding ? ND_NA_FLAG_ROUTER : 0) | ND_NA_FLAG_SOLICITED, 346 tlladdr, (struct sockaddr *)proxydl); 347 freeit: 348 if (ifa != NULL) 349 ifa_free(ifa); 350 m_freem(m); 351 return; 352 353 bad: 354 nd6log((LOG_ERR, "nd6_ns_input: src=%s\n", 355 ip6_sprintf(ip6bufs, &saddr6))); 356 nd6log((LOG_ERR, "nd6_ns_input: dst=%s\n", 357 ip6_sprintf(ip6bufs, &daddr6))); 358 nd6log((LOG_ERR, "nd6_ns_input: tgt=%s\n", 359 ip6_sprintf(ip6bufs, &taddr6))); 360 ICMP6STAT_INC(icp6s_badns); 361 if (ifa != NULL) 362 ifa_free(ifa); 363 m_freem(m); 364 } 365 366 /* 367 * Output a Neighbor Solicitation Message. Caller specifies: 368 * - ICMP6 header source IP6 address 369 * - ND6 header target IP6 address 370 * - ND6 header source datalink address 371 * 372 * Based on RFC 2461 373 * Based on RFC 2462 (duplicate address detection) 374 * 375 * ln - for source address determination 376 * dad - duplicate address detection 377 */ 378 void 379 nd6_ns_output(struct ifnet *ifp, const struct in6_addr *daddr6, 380 const struct in6_addr *taddr6, struct llentry *ln, int dad) 381 { 382 struct mbuf *m; 383 struct m_tag *mtag; 384 struct ip6_hdr *ip6; 385 struct nd_neighbor_solicit *nd_ns; 386 struct in6_addr *src, src_in; 387 struct ip6_moptions im6o; 388 int icmp6len; 389 int maxlen; 390 caddr_t mac; 391 struct route_in6 ro; 392 393 bzero(&ro, sizeof(ro)); 394 395 if (IN6_IS_ADDR_MULTICAST(taddr6)) 396 return; 397 398 /* estimate the size of message */ 399 maxlen = sizeof(*ip6) + sizeof(*nd_ns); 400 maxlen += (sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7; 401 if (max_linkhdr + maxlen >= MCLBYTES) { 402 #ifdef DIAGNOSTIC 403 printf("nd6_ns_output: max_linkhdr + maxlen >= MCLBYTES " 404 "(%d + %d > %d)\n", max_linkhdr, maxlen, MCLBYTES); 405 #endif 406 return; 407 } 408 409 MGETHDR(m, M_DONTWAIT, MT_DATA); 410 if (m && max_linkhdr + maxlen >= MHLEN) { 411 MCLGET(m, M_DONTWAIT); 412 if ((m->m_flags & M_EXT) == 0) { 413 m_free(m); 414 m = NULL; 415 } 416 } 417 if (m == NULL) 418 return; 419 m->m_pkthdr.rcvif = NULL; 420 421 if (daddr6 == NULL || IN6_IS_ADDR_MULTICAST(daddr6)) { 422 m->m_flags |= M_MCAST; 423 im6o.im6o_multicast_ifp = ifp; 424 im6o.im6o_multicast_hlim = 255; 425 im6o.im6o_multicast_loop = 0; 426 } 427 428 icmp6len = sizeof(*nd_ns); 429 m->m_pkthdr.len = m->m_len = sizeof(*ip6) + icmp6len; 430 m->m_data += max_linkhdr; /* or MH_ALIGN() equivalent? */ 431 432 /* fill neighbor solicitation packet */ 433 ip6 = mtod(m, struct ip6_hdr *); 434 ip6->ip6_flow = 0; 435 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 436 ip6->ip6_vfc |= IPV6_VERSION; 437 /* ip6->ip6_plen will be set later */ 438 ip6->ip6_nxt = IPPROTO_ICMPV6; 439 ip6->ip6_hlim = 255; 440 if (daddr6) 441 ip6->ip6_dst = *daddr6; 442 else { 443 ip6->ip6_dst.s6_addr16[0] = IPV6_ADDR_INT16_MLL; 444 ip6->ip6_dst.s6_addr16[1] = 0; 445 ip6->ip6_dst.s6_addr32[1] = 0; 446 ip6->ip6_dst.s6_addr32[2] = IPV6_ADDR_INT32_ONE; 447 ip6->ip6_dst.s6_addr32[3] = taddr6->s6_addr32[3]; 448 ip6->ip6_dst.s6_addr8[12] = 0xff; 449 if (in6_setscope(&ip6->ip6_dst, ifp, NULL) != 0) 450 goto bad; 451 } 452 if (!dad) { 453 struct ifaddr *ifa; 454 455 /* 456 * RFC2461 7.2.2: 457 * "If the source address of the packet prompting the 458 * solicitation is the same as one of the addresses assigned 459 * to the outgoing interface, that address SHOULD be placed 460 * in the IP Source Address of the outgoing solicitation. 461 * Otherwise, any one of the addresses assigned to the 462 * interface should be used." 463 * 464 * We use the source address for the prompting packet 465 * (saddr6), if: 466 * - saddr6 is given from the caller (by giving "ln"), and 467 * - saddr6 belongs to the outgoing interface. 468 * Otherwise, we perform the source address selection as usual. 469 */ 470 struct ip6_hdr *hip6; /* hold ip6 */ 471 struct in6_addr *hsrc = NULL; 472 473 if ((ln != NULL) && ln->la_hold) { 474 /* 475 * assuming every packet in la_hold has the same IP 476 * header 477 */ 478 hip6 = mtod(ln->la_hold, struct ip6_hdr *); 479 /* XXX pullup? */ 480 if (sizeof(*hip6) < ln->la_hold->m_len) 481 hsrc = &hip6->ip6_src; 482 else 483 hsrc = NULL; 484 } 485 if (hsrc && (ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, 486 hsrc)) != NULL) { 487 src = hsrc; 488 ifa_free(ifa); 489 } else { 490 int error; 491 struct sockaddr_in6 dst_sa; 492 493 bzero(&dst_sa, sizeof(dst_sa)); 494 dst_sa.sin6_family = AF_INET6; 495 dst_sa.sin6_len = sizeof(dst_sa); 496 dst_sa.sin6_addr = ip6->ip6_dst; 497 498 error = in6_selectsrc(&dst_sa, NULL, 499 NULL, &ro, NULL, NULL, &src_in); 500 if (error) { 501 char ip6buf[INET6_ADDRSTRLEN]; 502 nd6log((LOG_DEBUG, 503 "nd6_ns_output: source can't be " 504 "determined: dst=%s, error=%d\n", 505 ip6_sprintf(ip6buf, &dst_sa.sin6_addr), 506 error)); 507 goto bad; 508 } 509 src = &src_in; 510 } 511 } else { 512 /* 513 * Source address for DAD packet must always be IPv6 514 * unspecified address. (0::0) 515 * We actually don't have to 0-clear the address (we did it 516 * above), but we do so here explicitly to make the intention 517 * clearer. 518 */ 519 bzero(&src_in, sizeof(src_in)); 520 src = &src_in; 521 } 522 ip6->ip6_src = *src; 523 nd_ns = (struct nd_neighbor_solicit *)(ip6 + 1); 524 nd_ns->nd_ns_type = ND_NEIGHBOR_SOLICIT; 525 nd_ns->nd_ns_code = 0; 526 nd_ns->nd_ns_reserved = 0; 527 nd_ns->nd_ns_target = *taddr6; 528 in6_clearscope(&nd_ns->nd_ns_target); /* XXX */ 529 530 /* 531 * Add source link-layer address option. 532 * 533 * spec implementation 534 * --- --- 535 * DAD packet MUST NOT do not add the option 536 * there's no link layer address: 537 * impossible do not add the option 538 * there's link layer address: 539 * Multicast NS MUST add one add the option 540 * Unicast NS SHOULD add one add the option 541 */ 542 if (!dad && (mac = nd6_ifptomac(ifp))) { 543 int optlen = sizeof(struct nd_opt_hdr) + ifp->if_addrlen; 544 struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)(nd_ns + 1); 545 /* 8 byte alignments... */ 546 optlen = (optlen + 7) & ~7; 547 548 m->m_pkthdr.len += optlen; 549 m->m_len += optlen; 550 icmp6len += optlen; 551 bzero((caddr_t)nd_opt, optlen); 552 nd_opt->nd_opt_type = ND_OPT_SOURCE_LINKADDR; 553 nd_opt->nd_opt_len = optlen >> 3; 554 bcopy(mac, (caddr_t)(nd_opt + 1), ifp->if_addrlen); 555 } 556 557 ip6->ip6_plen = htons((u_short)icmp6len); 558 nd_ns->nd_ns_cksum = 0; 559 nd_ns->nd_ns_cksum = 560 in6_cksum(m, IPPROTO_ICMPV6, sizeof(*ip6), icmp6len); 561 562 if (send_sendso_input_hook != NULL) { 563 mtag = m_tag_get(PACKET_TAG_ND_OUTGOING, 564 sizeof(unsigned short), M_NOWAIT); 565 if (mtag == NULL) 566 goto bad; 567 *(unsigned short *)(mtag + 1) = nd_ns->nd_ns_type; 568 m_tag_prepend(m, mtag); 569 } 570 571 ip6_output(m, NULL, &ro, dad ? IPV6_UNSPECSRC : 0, &im6o, NULL, NULL); 572 icmp6_ifstat_inc(ifp, ifs6_out_msg); 573 icmp6_ifstat_inc(ifp, ifs6_out_neighborsolicit); 574 ICMP6STAT_INC(icp6s_outhist[ND_NEIGHBOR_SOLICIT]); 575 576 if (ro.ro_rt) { /* we don't cache this route. */ 577 RTFREE(ro.ro_rt); 578 } 579 return; 580 581 bad: 582 if (ro.ro_rt) { 583 RTFREE(ro.ro_rt); 584 } 585 m_freem(m); 586 return; 587 } 588 589 /* 590 * Neighbor advertisement input handling. 591 * 592 * Based on RFC 2461 593 * Based on RFC 2462 (duplicate address detection) 594 * 595 * the following items are not implemented yet: 596 * - proxy advertisement delay rule (RFC2461 7.2.8, last paragraph, SHOULD) 597 * - anycast advertisement delay rule (RFC2461 7.2.7, SHOULD) 598 */ 599 void 600 nd6_na_input(struct mbuf *m, int off, int icmp6len) 601 { 602 struct ifnet *ifp = m->m_pkthdr.rcvif; 603 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 604 struct nd_neighbor_advert *nd_na; 605 struct in6_addr daddr6 = ip6->ip6_dst; 606 struct in6_addr taddr6; 607 int flags; 608 int is_router; 609 int is_solicited; 610 int is_override; 611 char *lladdr = NULL; 612 int lladdrlen = 0; 613 int checklink = 0; 614 struct ifaddr *ifa; 615 struct llentry *ln = NULL; 616 union nd_opts ndopts; 617 struct mbuf *chain = NULL; 618 struct m_tag *mtag; 619 struct sockaddr_in6 sin6; 620 char ip6bufs[INET6_ADDRSTRLEN], ip6bufd[INET6_ADDRSTRLEN]; 621 622 if (ip6->ip6_hlim != 255) { 623 nd6log((LOG_ERR, 624 "nd6_na_input: invalid hlim (%d) from %s to %s on %s\n", 625 ip6->ip6_hlim, ip6_sprintf(ip6bufs, &ip6->ip6_src), 626 ip6_sprintf(ip6bufd, &ip6->ip6_dst), if_name(ifp))); 627 goto bad; 628 } 629 630 #ifndef PULLDOWN_TEST 631 IP6_EXTHDR_CHECK(m, off, icmp6len,); 632 nd_na = (struct nd_neighbor_advert *)((caddr_t)ip6 + off); 633 #else 634 IP6_EXTHDR_GET(nd_na, struct nd_neighbor_advert *, m, off, icmp6len); 635 if (nd_na == NULL) { 636 ICMP6STAT_INC(icp6s_tooshort); 637 return; 638 } 639 #endif 640 641 flags = nd_na->nd_na_flags_reserved; 642 is_router = ((flags & ND_NA_FLAG_ROUTER) != 0); 643 is_solicited = ((flags & ND_NA_FLAG_SOLICITED) != 0); 644 is_override = ((flags & ND_NA_FLAG_OVERRIDE) != 0); 645 646 taddr6 = nd_na->nd_na_target; 647 if (in6_setscope(&taddr6, ifp, NULL)) 648 goto bad; /* XXX: impossible */ 649 650 if (IN6_IS_ADDR_MULTICAST(&taddr6)) { 651 nd6log((LOG_ERR, 652 "nd6_na_input: invalid target address %s\n", 653 ip6_sprintf(ip6bufs, &taddr6))); 654 goto bad; 655 } 656 if (IN6_IS_ADDR_MULTICAST(&daddr6)) 657 if (is_solicited) { 658 nd6log((LOG_ERR, 659 "nd6_na_input: a solicited adv is multicasted\n")); 660 goto bad; 661 } 662 663 icmp6len -= sizeof(*nd_na); 664 nd6_option_init(nd_na + 1, icmp6len, &ndopts); 665 if (nd6_options(&ndopts) < 0) { 666 nd6log((LOG_INFO, 667 "nd6_na_input: invalid ND option, ignored\n")); 668 /* nd6_options have incremented stats */ 669 goto freeit; 670 } 671 672 if (ndopts.nd_opts_tgt_lladdr) { 673 lladdr = (char *)(ndopts.nd_opts_tgt_lladdr + 1); 674 lladdrlen = ndopts.nd_opts_tgt_lladdr->nd_opt_len << 3; 675 } 676 677 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &taddr6); 678 679 /* 680 * Target address matches one of my interface address. 681 * 682 * If my address is tentative, this means that there's somebody 683 * already using the same address as mine. This indicates DAD failure. 684 * This is defined in RFC 2462. 685 * 686 * Otherwise, process as defined in RFC 2461. 687 */ 688 if (ifa 689 && (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_TENTATIVE)) { 690 ifa_free(ifa); 691 nd6_dad_na_input(ifa); 692 goto freeit; 693 } 694 695 /* Just for safety, maybe unnecessary. */ 696 if (ifa) { 697 ifa_free(ifa); 698 log(LOG_ERR, 699 "nd6_na_input: duplicate IP6 address %s\n", 700 ip6_sprintf(ip6bufs, &taddr6)); 701 goto freeit; 702 } 703 704 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) { 705 nd6log((LOG_INFO, "nd6_na_input: lladdrlen mismatch for %s " 706 "(if %d, NA packet %d)\n", ip6_sprintf(ip6bufs, &taddr6), 707 ifp->if_addrlen, lladdrlen - 2)); 708 goto bad; 709 } 710 711 /* 712 * If no neighbor cache entry is found, NA SHOULD silently be 713 * discarded. 714 */ 715 IF_AFDATA_LOCK(ifp); 716 ln = nd6_lookup(&taddr6, LLE_EXCLUSIVE, ifp); 717 IF_AFDATA_UNLOCK(ifp); 718 if (ln == NULL) { 719 goto freeit; 720 } 721 722 if (ln->ln_state == ND6_LLINFO_INCOMPLETE) { 723 /* 724 * If the link-layer has address, and no lladdr option came, 725 * discard the packet. 726 */ 727 if (ifp->if_addrlen && lladdr == NULL) { 728 goto freeit; 729 } 730 731 /* 732 * Record link-layer address, and update the state. 733 */ 734 bcopy(lladdr, &ln->ll_addr, ifp->if_addrlen); 735 ln->la_flags |= LLE_VALID; 736 if (is_solicited) { 737 ln->ln_state = ND6_LLINFO_REACHABLE; 738 ln->ln_byhint = 0; 739 if (!ND6_LLINFO_PERMANENT(ln)) { 740 nd6_llinfo_settimer_locked(ln, 741 (long)ND_IFINFO(ln->lle_tbl->llt_ifp)->reachable * hz); 742 } 743 } else { 744 ln->ln_state = ND6_LLINFO_STALE; 745 nd6_llinfo_settimer_locked(ln, (long)V_nd6_gctimer * hz); 746 } 747 if ((ln->ln_router = is_router) != 0) { 748 /* 749 * This means a router's state has changed from 750 * non-reachable to probably reachable, and might 751 * affect the status of associated prefixes.. 752 */ 753 checklink = 1; 754 } 755 } else { 756 int llchange; 757 758 /* 759 * Check if the link-layer address has changed or not. 760 */ 761 if (lladdr == NULL) 762 llchange = 0; 763 else { 764 if (ln->la_flags & LLE_VALID) { 765 if (bcmp(lladdr, &ln->ll_addr, ifp->if_addrlen)) 766 llchange = 1; 767 else 768 llchange = 0; 769 } else 770 llchange = 1; 771 } 772 773 /* 774 * This is VERY complex. Look at it with care. 775 * 776 * override solicit lladdr llchange action 777 * (L: record lladdr) 778 * 779 * 0 0 n -- (2c) 780 * 0 0 y n (2b) L 781 * 0 0 y y (1) REACHABLE->STALE 782 * 0 1 n -- (2c) *->REACHABLE 783 * 0 1 y n (2b) L *->REACHABLE 784 * 0 1 y y (1) REACHABLE->STALE 785 * 1 0 n -- (2a) 786 * 1 0 y n (2a) L 787 * 1 0 y y (2a) L *->STALE 788 * 1 1 n -- (2a) *->REACHABLE 789 * 1 1 y n (2a) L *->REACHABLE 790 * 1 1 y y (2a) L *->REACHABLE 791 */ 792 if (!is_override && (lladdr != NULL && llchange)) { /* (1) */ 793 /* 794 * If state is REACHABLE, make it STALE. 795 * no other updates should be done. 796 */ 797 if (ln->ln_state == ND6_LLINFO_REACHABLE) { 798 ln->ln_state = ND6_LLINFO_STALE; 799 nd6_llinfo_settimer_locked(ln, (long)V_nd6_gctimer * hz); 800 } 801 goto freeit; 802 } else if (is_override /* (2a) */ 803 || (!is_override && (lladdr != NULL && !llchange)) /* (2b) */ 804 || lladdr == NULL) { /* (2c) */ 805 /* 806 * Update link-local address, if any. 807 */ 808 if (lladdr != NULL) { 809 bcopy(lladdr, &ln->ll_addr, ifp->if_addrlen); 810 ln->la_flags |= LLE_VALID; 811 } 812 813 /* 814 * If solicited, make the state REACHABLE. 815 * If not solicited and the link-layer address was 816 * changed, make it STALE. 817 */ 818 if (is_solicited) { 819 ln->ln_state = ND6_LLINFO_REACHABLE; 820 ln->ln_byhint = 0; 821 if (!ND6_LLINFO_PERMANENT(ln)) { 822 nd6_llinfo_settimer_locked(ln, 823 (long)ND_IFINFO(ifp)->reachable * hz); 824 } 825 } else { 826 if (lladdr != NULL && llchange) { 827 ln->ln_state = ND6_LLINFO_STALE; 828 nd6_llinfo_settimer_locked(ln, 829 (long)V_nd6_gctimer * hz); 830 } 831 } 832 } 833 834 if (ln->ln_router && !is_router) { 835 /* 836 * The peer dropped the router flag. 837 * Remove the sender from the Default Router List and 838 * update the Destination Cache entries. 839 */ 840 struct nd_defrouter *dr; 841 struct in6_addr *in6; 842 843 in6 = &L3_ADDR_SIN6(ln)->sin6_addr; 844 845 /* 846 * Lock to protect the default router list. 847 * XXX: this might be unnecessary, since this function 848 * is only called under the network software interrupt 849 * context. However, we keep it just for safety. 850 */ 851 dr = defrouter_lookup(in6, ln->lle_tbl->llt_ifp); 852 if (dr) 853 defrtrlist_del(dr); 854 else if (!V_ip6_forwarding) { 855 /* 856 * Even if the neighbor is not in the default 857 * router list, the neighbor may be used 858 * as a next hop for some destinations 859 * (e.g. redirect case). So we must 860 * call rt6_flush explicitly. 861 */ 862 rt6_flush(&ip6->ip6_src, ifp); 863 } 864 } 865 ln->ln_router = is_router; 866 } 867 /* XXX - QL 868 * Does this matter? 869 * rt->rt_flags &= ~RTF_REJECT; 870 */ 871 ln->la_asked = 0; 872 if (ln->la_hold) { 873 struct mbuf *m_hold, *m_hold_next; 874 875 /* 876 * reset the la_hold in advance, to explicitly 877 * prevent a la_hold lookup in nd6_output() 878 * (wouldn't happen, though...) 879 */ 880 for (m_hold = ln->la_hold, ln->la_hold = NULL; 881 m_hold; m_hold = m_hold_next) { 882 m_hold_next = m_hold->m_nextpkt; 883 m_hold->m_nextpkt = NULL; 884 /* 885 * we assume ifp is not a loopback here, so just set 886 * the 2nd argument as the 1st one. 887 */ 888 889 if (send_sendso_input_hook != NULL) { 890 mtag = m_tag_get(PACKET_TAG_ND_OUTGOING, 891 sizeof(unsigned short), M_NOWAIT); 892 if (mtag == NULL) 893 goto bad; 894 m_tag_prepend(m, mtag); 895 } 896 897 nd6_output_lle(ifp, ifp, m_hold, L3_ADDR_SIN6(ln), NULL, ln, &chain); 898 } 899 } 900 freeit: 901 if (ln != NULL) { 902 if (chain) 903 memcpy(&sin6, L3_ADDR_SIN6(ln), sizeof(sin6)); 904 LLE_WUNLOCK(ln); 905 906 if (chain) 907 nd6_output_flush(ifp, ifp, chain, &sin6, NULL); 908 } 909 if (checklink) 910 pfxlist_onlink_check(); 911 912 m_freem(m); 913 return; 914 915 bad: 916 if (ln != NULL) 917 LLE_WUNLOCK(ln); 918 919 ICMP6STAT_INC(icp6s_badna); 920 m_freem(m); 921 } 922 923 /* 924 * Neighbor advertisement output handling. 925 * 926 * Based on RFC 2461 927 * 928 * the following items are not implemented yet: 929 * - proxy advertisement delay rule (RFC2461 7.2.8, last paragraph, SHOULD) 930 * - anycast advertisement delay rule (RFC2461 7.2.7, SHOULD) 931 * 932 * tlladdr - 1 if include target link-layer address 933 * sdl0 - sockaddr_dl (= proxy NA) or NULL 934 */ 935 void 936 nd6_na_output(struct ifnet *ifp, const struct in6_addr *daddr6_0, 937 const struct in6_addr *taddr6, u_long flags, int tlladdr, 938 struct sockaddr *sdl0) 939 { 940 struct mbuf *m; 941 struct m_tag *mtag; 942 struct ip6_hdr *ip6; 943 struct nd_neighbor_advert *nd_na; 944 struct ip6_moptions im6o; 945 struct in6_addr src, daddr6; 946 struct sockaddr_in6 dst_sa; 947 int icmp6len, maxlen, error; 948 caddr_t mac = NULL; 949 struct route_in6 ro; 950 951 bzero(&ro, sizeof(ro)); 952 953 daddr6 = *daddr6_0; /* make a local copy for modification */ 954 955 /* estimate the size of message */ 956 maxlen = sizeof(*ip6) + sizeof(*nd_na); 957 maxlen += (sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7; 958 if (max_linkhdr + maxlen >= MCLBYTES) { 959 #ifdef DIAGNOSTIC 960 printf("nd6_na_output: max_linkhdr + maxlen >= MCLBYTES " 961 "(%d + %d > %d)\n", max_linkhdr, maxlen, MCLBYTES); 962 #endif 963 return; 964 } 965 966 MGETHDR(m, M_DONTWAIT, MT_DATA); 967 if (m && max_linkhdr + maxlen >= MHLEN) { 968 MCLGET(m, M_DONTWAIT); 969 if ((m->m_flags & M_EXT) == 0) { 970 m_free(m); 971 m = NULL; 972 } 973 } 974 if (m == NULL) 975 return; 976 m->m_pkthdr.rcvif = NULL; 977 978 if (IN6_IS_ADDR_MULTICAST(&daddr6)) { 979 m->m_flags |= M_MCAST; 980 im6o.im6o_multicast_ifp = ifp; 981 im6o.im6o_multicast_hlim = 255; 982 im6o.im6o_multicast_loop = 0; 983 } 984 985 icmp6len = sizeof(*nd_na); 986 m->m_pkthdr.len = m->m_len = sizeof(struct ip6_hdr) + icmp6len; 987 m->m_data += max_linkhdr; /* or MH_ALIGN() equivalent? */ 988 989 /* fill neighbor advertisement packet */ 990 ip6 = mtod(m, struct ip6_hdr *); 991 ip6->ip6_flow = 0; 992 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 993 ip6->ip6_vfc |= IPV6_VERSION; 994 ip6->ip6_nxt = IPPROTO_ICMPV6; 995 ip6->ip6_hlim = 255; 996 if (IN6_IS_ADDR_UNSPECIFIED(&daddr6)) { 997 /* reply to DAD */ 998 daddr6.s6_addr16[0] = IPV6_ADDR_INT16_MLL; 999 daddr6.s6_addr16[1] = 0; 1000 daddr6.s6_addr32[1] = 0; 1001 daddr6.s6_addr32[2] = 0; 1002 daddr6.s6_addr32[3] = IPV6_ADDR_INT32_ONE; 1003 if (in6_setscope(&daddr6, ifp, NULL)) 1004 goto bad; 1005 1006 flags &= ~ND_NA_FLAG_SOLICITED; 1007 } 1008 ip6->ip6_dst = daddr6; 1009 bzero(&dst_sa, sizeof(struct sockaddr_in6)); 1010 dst_sa.sin6_family = AF_INET6; 1011 dst_sa.sin6_len = sizeof(struct sockaddr_in6); 1012 dst_sa.sin6_addr = daddr6; 1013 1014 /* 1015 * Select a source whose scope is the same as that of the dest. 1016 */ 1017 bcopy(&dst_sa, &ro.ro_dst, sizeof(dst_sa)); 1018 error = in6_selectsrc(&dst_sa, NULL, NULL, &ro, NULL, NULL, &src); 1019 if (error) { 1020 char ip6buf[INET6_ADDRSTRLEN]; 1021 nd6log((LOG_DEBUG, "nd6_na_output: source can't be " 1022 "determined: dst=%s, error=%d\n", 1023 ip6_sprintf(ip6buf, &dst_sa.sin6_addr), error)); 1024 goto bad; 1025 } 1026 ip6->ip6_src = src; 1027 nd_na = (struct nd_neighbor_advert *)(ip6 + 1); 1028 nd_na->nd_na_type = ND_NEIGHBOR_ADVERT; 1029 nd_na->nd_na_code = 0; 1030 nd_na->nd_na_target = *taddr6; 1031 in6_clearscope(&nd_na->nd_na_target); /* XXX */ 1032 1033 /* 1034 * "tlladdr" indicates NS's condition for adding tlladdr or not. 1035 * see nd6_ns_input() for details. 1036 * Basically, if NS packet is sent to unicast/anycast addr, 1037 * target lladdr option SHOULD NOT be included. 1038 */ 1039 if (tlladdr) { 1040 /* 1041 * sdl0 != NULL indicates proxy NA. If we do proxy, use 1042 * lladdr in sdl0. If we are not proxying (sending NA for 1043 * my address) use lladdr configured for the interface. 1044 */ 1045 if (sdl0 == NULL) { 1046 if (ifp->if_carp) 1047 mac = (*carp_macmatch6_p)(ifp, m, taddr6); 1048 if (mac == NULL) 1049 mac = nd6_ifptomac(ifp); 1050 } else if (sdl0->sa_family == AF_LINK) { 1051 struct sockaddr_dl *sdl; 1052 sdl = (struct sockaddr_dl *)sdl0; 1053 if (sdl->sdl_alen == ifp->if_addrlen) 1054 mac = LLADDR(sdl); 1055 } 1056 } 1057 if (tlladdr && mac) { 1058 int optlen = sizeof(struct nd_opt_hdr) + ifp->if_addrlen; 1059 struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)(nd_na + 1); 1060 1061 /* roundup to 8 bytes alignment! */ 1062 optlen = (optlen + 7) & ~7; 1063 1064 m->m_pkthdr.len += optlen; 1065 m->m_len += optlen; 1066 icmp6len += optlen; 1067 bzero((caddr_t)nd_opt, optlen); 1068 nd_opt->nd_opt_type = ND_OPT_TARGET_LINKADDR; 1069 nd_opt->nd_opt_len = optlen >> 3; 1070 bcopy(mac, (caddr_t)(nd_opt + 1), ifp->if_addrlen); 1071 } else 1072 flags &= ~ND_NA_FLAG_OVERRIDE; 1073 1074 ip6->ip6_plen = htons((u_short)icmp6len); 1075 nd_na->nd_na_flags_reserved = flags; 1076 nd_na->nd_na_cksum = 0; 1077 nd_na->nd_na_cksum = 1078 in6_cksum(m, IPPROTO_ICMPV6, sizeof(struct ip6_hdr), icmp6len); 1079 1080 if (send_sendso_input_hook != NULL) { 1081 mtag = m_tag_get(PACKET_TAG_ND_OUTGOING, 1082 sizeof(unsigned short), M_NOWAIT); 1083 if (mtag == NULL) 1084 goto bad; 1085 *(unsigned short *)(mtag + 1) = nd_na->nd_na_type; 1086 m_tag_prepend(m, mtag); 1087 } 1088 1089 ip6_output(m, NULL, &ro, 0, &im6o, NULL, NULL); 1090 icmp6_ifstat_inc(ifp, ifs6_out_msg); 1091 icmp6_ifstat_inc(ifp, ifs6_out_neighboradvert); 1092 ICMP6STAT_INC(icp6s_outhist[ND_NEIGHBOR_ADVERT]); 1093 1094 if (ro.ro_rt) { /* we don't cache this route. */ 1095 RTFREE(ro.ro_rt); 1096 } 1097 return; 1098 1099 bad: 1100 if (ro.ro_rt) { 1101 RTFREE(ro.ro_rt); 1102 } 1103 m_freem(m); 1104 return; 1105 } 1106 1107 caddr_t 1108 nd6_ifptomac(struct ifnet *ifp) 1109 { 1110 switch (ifp->if_type) { 1111 case IFT_ARCNET: 1112 case IFT_ETHER: 1113 case IFT_FDDI: 1114 case IFT_IEEE1394: 1115 #ifdef IFT_L2VLAN 1116 case IFT_L2VLAN: 1117 #endif 1118 #ifdef IFT_IEEE80211 1119 case IFT_IEEE80211: 1120 #endif 1121 #ifdef IFT_CARP 1122 case IFT_CARP: 1123 #endif 1124 case IFT_BRIDGE: 1125 case IFT_ISO88025: 1126 return IF_LLADDR(ifp); 1127 default: 1128 return NULL; 1129 } 1130 } 1131 1132 struct dadq { 1133 TAILQ_ENTRY(dadq) dad_list; 1134 struct ifaddr *dad_ifa; 1135 int dad_count; /* max NS to send */ 1136 int dad_ns_tcount; /* # of trials to send NS */ 1137 int dad_ns_ocount; /* NS sent so far */ 1138 int dad_ns_icount; 1139 int dad_na_icount; 1140 struct callout dad_timer_ch; 1141 struct vnet *dad_vnet; 1142 }; 1143 1144 static VNET_DEFINE(TAILQ_HEAD(, dadq), dadq); 1145 VNET_DEFINE(int, dad_init) = 0; 1146 #define V_dadq VNET(dadq) 1147 #define V_dad_init VNET(dad_init) 1148 1149 static struct dadq * 1150 nd6_dad_find(struct ifaddr *ifa) 1151 { 1152 struct dadq *dp; 1153 1154 for (dp = V_dadq.tqh_first; dp; dp = dp->dad_list.tqe_next) { 1155 if (dp->dad_ifa == ifa) 1156 return dp; 1157 } 1158 return NULL; 1159 } 1160 1161 static void 1162 nd6_dad_starttimer(struct dadq *dp, int ticks) 1163 { 1164 1165 callout_reset(&dp->dad_timer_ch, ticks, 1166 (void (*)(void *))nd6_dad_timer, (void *)dp); 1167 } 1168 1169 static void 1170 nd6_dad_stoptimer(struct dadq *dp) 1171 { 1172 1173 callout_stop(&dp->dad_timer_ch); 1174 } 1175 1176 /* 1177 * Start Duplicate Address Detection (DAD) for specified interface address. 1178 */ 1179 void 1180 nd6_dad_start(struct ifaddr *ifa, int delay) 1181 { 1182 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1183 struct dadq *dp; 1184 char ip6buf[INET6_ADDRSTRLEN]; 1185 1186 if (!V_dad_init) { 1187 TAILQ_INIT(&V_dadq); 1188 V_dad_init++; 1189 } 1190 1191 /* 1192 * If we don't need DAD, don't do it. 1193 * There are several cases: 1194 * - DAD is disabled (ip6_dad_count == 0) 1195 * - the interface address is anycast 1196 */ 1197 if (!(ia->ia6_flags & IN6_IFF_TENTATIVE)) { 1198 log(LOG_DEBUG, 1199 "nd6_dad_start: called with non-tentative address " 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 if (ia->ia6_flags & IN6_IFF_ANYCAST) { 1206 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1207 return; 1208 } 1209 if (!V_ip6_dad_count) { 1210 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1211 return; 1212 } 1213 if (ifa->ifa_ifp == NULL) 1214 panic("nd6_dad_start: ifa->ifa_ifp == NULL"); 1215 if (!(ifa->ifa_ifp->if_flags & IFF_UP)) { 1216 return; 1217 } 1218 if (ND_IFINFO(ifa->ifa_ifp)->flags & ND6_IFF_IFDISABLED) 1219 return; 1220 if (nd6_dad_find(ifa) != NULL) { 1221 /* DAD already in progress */ 1222 return; 1223 } 1224 1225 dp = malloc(sizeof(*dp), M_IP6NDP, M_NOWAIT); 1226 if (dp == NULL) { 1227 log(LOG_ERR, "nd6_dad_start: memory allocation failed for " 1228 "%s(%s)\n", 1229 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr), 1230 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1231 return; 1232 } 1233 bzero(dp, sizeof(*dp)); 1234 callout_init(&dp->dad_timer_ch, 0); 1235 #ifdef VIMAGE 1236 dp->dad_vnet = curvnet; 1237 #endif 1238 TAILQ_INSERT_TAIL(&V_dadq, (struct dadq *)dp, dad_list); 1239 1240 nd6log((LOG_DEBUG, "%s: starting DAD for %s\n", if_name(ifa->ifa_ifp), 1241 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr))); 1242 1243 /* 1244 * Send NS packet for DAD, ip6_dad_count times. 1245 * Note that we must delay the first transmission, if this is the 1246 * first packet to be sent from the interface after interface 1247 * (re)initialization. 1248 */ 1249 dp->dad_ifa = ifa; 1250 ifa_ref(ifa); /* just for safety */ 1251 dp->dad_count = V_ip6_dad_count; 1252 dp->dad_ns_icount = dp->dad_na_icount = 0; 1253 dp->dad_ns_ocount = dp->dad_ns_tcount = 0; 1254 if (delay == 0) { 1255 nd6_dad_ns_output(dp, ifa); 1256 nd6_dad_starttimer(dp, 1257 (long)ND_IFINFO(ifa->ifa_ifp)->retrans * hz / 1000); 1258 } else { 1259 nd6_dad_starttimer(dp, delay); 1260 } 1261 } 1262 1263 /* 1264 * terminate DAD unconditionally. used for address removals. 1265 */ 1266 void 1267 nd6_dad_stop(struct ifaddr *ifa) 1268 { 1269 struct dadq *dp; 1270 1271 if (!V_dad_init) 1272 return; 1273 dp = nd6_dad_find(ifa); 1274 if (!dp) { 1275 /* DAD wasn't started yet */ 1276 return; 1277 } 1278 1279 nd6_dad_stoptimer(dp); 1280 1281 TAILQ_REMOVE(&V_dadq, (struct dadq *)dp, dad_list); 1282 free(dp, M_IP6NDP); 1283 dp = NULL; 1284 ifa_free(ifa); 1285 } 1286 1287 static void 1288 nd6_dad_timer(struct dadq *dp) 1289 { 1290 CURVNET_SET(dp->dad_vnet); 1291 int s; 1292 struct ifaddr *ifa = dp->dad_ifa; 1293 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1294 char ip6buf[INET6_ADDRSTRLEN]; 1295 1296 s = splnet(); /* XXX */ 1297 1298 /* Sanity check */ 1299 if (ia == NULL) { 1300 log(LOG_ERR, "nd6_dad_timer: called with null parameter\n"); 1301 goto done; 1302 } 1303 if (ia->ia6_flags & IN6_IFF_DUPLICATED) { 1304 log(LOG_ERR, "nd6_dad_timer: called with duplicated address " 1305 "%s(%s)\n", 1306 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr), 1307 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1308 goto done; 1309 } 1310 if ((ia->ia6_flags & IN6_IFF_TENTATIVE) == 0) { 1311 log(LOG_ERR, "nd6_dad_timer: called with non-tentative address " 1312 "%s(%s)\n", 1313 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr), 1314 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1315 goto done; 1316 } 1317 1318 /* timeouted with IFF_{RUNNING,UP} check */ 1319 if (dp->dad_ns_tcount > V_dad_maxtry) { 1320 nd6log((LOG_INFO, "%s: could not run DAD, driver problem?\n", 1321 if_name(ifa->ifa_ifp))); 1322 1323 TAILQ_REMOVE(&V_dadq, (struct dadq *)dp, dad_list); 1324 free(dp, M_IP6NDP); 1325 dp = NULL; 1326 ifa_free(ifa); 1327 goto done; 1328 } 1329 1330 /* Need more checks? */ 1331 if (dp->dad_ns_ocount < dp->dad_count) { 1332 /* 1333 * We have more NS to go. Send NS packet for DAD. 1334 */ 1335 nd6_dad_ns_output(dp, ifa); 1336 nd6_dad_starttimer(dp, 1337 (long)ND_IFINFO(ifa->ifa_ifp)->retrans * hz / 1000); 1338 } else { 1339 /* 1340 * We have transmitted sufficient number of DAD packets. 1341 * See what we've got. 1342 */ 1343 int duplicate; 1344 1345 duplicate = 0; 1346 1347 if (dp->dad_na_icount) { 1348 /* 1349 * the check is in nd6_dad_na_input(), 1350 * but just in case 1351 */ 1352 duplicate++; 1353 } 1354 1355 if (dp->dad_ns_icount) { 1356 /* We've seen NS, means DAD has failed. */ 1357 duplicate++; 1358 } 1359 1360 if (duplicate) { 1361 /* (*dp) will be freed in nd6_dad_duplicated() */ 1362 dp = NULL; 1363 nd6_dad_duplicated(ifa); 1364 } else { 1365 /* 1366 * We are done with DAD. No NA came, no NS came. 1367 * No duplicate address found. 1368 */ 1369 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1370 1371 nd6log((LOG_DEBUG, 1372 "%s: DAD complete for %s - no duplicates found\n", 1373 if_name(ifa->ifa_ifp), 1374 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr))); 1375 1376 TAILQ_REMOVE(&V_dadq, (struct dadq *)dp, dad_list); 1377 free(dp, M_IP6NDP); 1378 dp = NULL; 1379 ifa_free(ifa); 1380 } 1381 } 1382 1383 done: 1384 splx(s); 1385 CURVNET_RESTORE(); 1386 } 1387 1388 void 1389 nd6_dad_duplicated(struct ifaddr *ifa) 1390 { 1391 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1392 struct ifnet *ifp; 1393 struct dadq *dp; 1394 char ip6buf[INET6_ADDRSTRLEN]; 1395 1396 dp = nd6_dad_find(ifa); 1397 if (dp == NULL) { 1398 log(LOG_ERR, "nd6_dad_duplicated: DAD structure not found\n"); 1399 return; 1400 } 1401 1402 log(LOG_ERR, "%s: DAD detected duplicate IPv6 address %s: " 1403 "NS in/out=%d/%d, NA in=%d\n", 1404 if_name(ifa->ifa_ifp), ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr), 1405 dp->dad_ns_icount, dp->dad_ns_ocount, dp->dad_na_icount); 1406 1407 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1408 ia->ia6_flags |= IN6_IFF_DUPLICATED; 1409 1410 /* We are done with DAD, with duplicate address found. (failure) */ 1411 nd6_dad_stoptimer(dp); 1412 1413 ifp = ifa->ifa_ifp; 1414 log(LOG_ERR, "%s: DAD complete for %s - duplicate found\n", 1415 if_name(ifp), ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr)); 1416 log(LOG_ERR, "%s: manual intervention required\n", 1417 if_name(ifp)); 1418 1419 /* 1420 * If the address is a link-local address formed from an interface 1421 * identifier based on the hardware address which is supposed to be 1422 * uniquely assigned (e.g., EUI-64 for an Ethernet interface), IP 1423 * operation on the interface SHOULD be disabled. 1424 * [RFC 4862, Section 5.4.5] 1425 */ 1426 if (IN6_IS_ADDR_LINKLOCAL(&ia->ia_addr.sin6_addr)) { 1427 struct in6_addr in6; 1428 1429 /* 1430 * To avoid over-reaction, we only apply this logic when we are 1431 * very sure that hardware addresses are supposed to be unique. 1432 */ 1433 switch (ifp->if_type) { 1434 case IFT_ETHER: 1435 case IFT_FDDI: 1436 case IFT_ATM: 1437 case IFT_IEEE1394: 1438 #ifdef IFT_IEEE80211 1439 case IFT_IEEE80211: 1440 #endif 1441 in6 = ia->ia_addr.sin6_addr; 1442 if (in6_get_hw_ifid(ifp, &in6) == 0 && 1443 IN6_ARE_ADDR_EQUAL(&ia->ia_addr.sin6_addr, &in6)) { 1444 ND_IFINFO(ifp)->flags |= ND6_IFF_IFDISABLED; 1445 log(LOG_ERR, "%s: possible hardware address " 1446 "duplication detected, disable IPv6\n", 1447 if_name(ifp)); 1448 } 1449 break; 1450 } 1451 } 1452 1453 TAILQ_REMOVE(&V_dadq, (struct dadq *)dp, dad_list); 1454 free(dp, M_IP6NDP); 1455 dp = NULL; 1456 ifa_free(ifa); 1457 } 1458 1459 static void 1460 nd6_dad_ns_output(struct dadq *dp, struct ifaddr *ifa) 1461 { 1462 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1463 struct ifnet *ifp = ifa->ifa_ifp; 1464 1465 dp->dad_ns_tcount++; 1466 if ((ifp->if_flags & IFF_UP) == 0) { 1467 return; 1468 } 1469 if ((ifp->if_drv_flags & IFF_DRV_RUNNING) == 0) { 1470 return; 1471 } 1472 1473 dp->dad_ns_ocount++; 1474 nd6_ns_output(ifp, NULL, &ia->ia_addr.sin6_addr, NULL, 1); 1475 } 1476 1477 static void 1478 nd6_dad_ns_input(struct ifaddr *ifa) 1479 { 1480 struct in6_ifaddr *ia; 1481 struct ifnet *ifp; 1482 const struct in6_addr *taddr6; 1483 struct dadq *dp; 1484 int duplicate; 1485 1486 if (ifa == NULL) 1487 panic("ifa == NULL in nd6_dad_ns_input"); 1488 1489 ia = (struct in6_ifaddr *)ifa; 1490 ifp = ifa->ifa_ifp; 1491 taddr6 = &ia->ia_addr.sin6_addr; 1492 duplicate = 0; 1493 dp = nd6_dad_find(ifa); 1494 1495 /* Quickhack - completely ignore DAD NS packets */ 1496 if (V_dad_ignore_ns) { 1497 char ip6buf[INET6_ADDRSTRLEN]; 1498 nd6log((LOG_INFO, 1499 "nd6_dad_ns_input: ignoring DAD NS packet for " 1500 "address %s(%s)\n", ip6_sprintf(ip6buf, taddr6), 1501 if_name(ifa->ifa_ifp))); 1502 return; 1503 } 1504 1505 /* 1506 * if I'm yet to start DAD, someone else started using this address 1507 * first. I have a duplicate and you win. 1508 */ 1509 if (dp == NULL || dp->dad_ns_ocount == 0) 1510 duplicate++; 1511 1512 /* XXX more checks for loopback situation - see nd6_dad_timer too */ 1513 1514 if (duplicate) { 1515 dp = NULL; /* will be freed in nd6_dad_duplicated() */ 1516 nd6_dad_duplicated(ifa); 1517 } else { 1518 /* 1519 * not sure if I got a duplicate. 1520 * increment ns count and see what happens. 1521 */ 1522 if (dp) 1523 dp->dad_ns_icount++; 1524 } 1525 } 1526 1527 static void 1528 nd6_dad_na_input(struct ifaddr *ifa) 1529 { 1530 struct dadq *dp; 1531 1532 if (ifa == NULL) 1533 panic("ifa == NULL in nd6_dad_na_input"); 1534 1535 dp = nd6_dad_find(ifa); 1536 if (dp) 1537 dp->dad_na_icount++; 1538 1539 /* remove the address. */ 1540 nd6_dad_duplicated(ifa); 1541 } 1542