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_carp.h" 39 #include "opt_mpath.h" 40 41 #include <sys/param.h> 42 #include <sys/systm.h> 43 #include <sys/malloc.h> 44 #include <sys/mbuf.h> 45 #include <sys/socket.h> 46 #include <sys/sockio.h> 47 #include <sys/time.h> 48 #include <sys/kernel.h> 49 #include <sys/errno.h> 50 #include <sys/syslog.h> 51 #include <sys/queue.h> 52 #include <sys/callout.h> 53 #include <sys/vimage.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 <netinet6/in6_var.h> 67 #include <netinet6/in6_ifattach.h> 68 #include <netinet/ip6.h> 69 #include <netinet6/ip6_var.h> 70 #include <netinet6/scope6_var.h> 71 #include <netinet6/nd6.h> 72 #include <netinet/icmp6.h> 73 74 #ifdef DEV_CARP 75 #include <netinet/ip_carp.h> 76 #endif 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 ifaddr *); 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 #ifdef VIMAGE_GLOBALS 90 int dad_ignore_ns; 91 int dad_maxtry; 92 #endif 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 INIT_VNET_INET6(curvnet); 104 struct ifnet *ifp = m->m_pkthdr.rcvif; 105 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 106 struct nd_neighbor_solicit *nd_ns; 107 struct in6_addr saddr6 = ip6->ip6_src; 108 struct in6_addr daddr6 = ip6->ip6_dst; 109 struct in6_addr taddr6; 110 struct in6_addr myaddr6; 111 char *lladdr = NULL; 112 struct ifaddr *ifa = NULL; 113 int lladdrlen = 0; 114 int anycast = 0, proxy = 0, tentative = 0; 115 int tlladdr; 116 union nd_opts ndopts; 117 struct sockaddr_dl *proxydl = NULL; 118 char ip6bufs[INET6_ADDRSTRLEN], ip6bufd[INET6_ADDRSTRLEN]; 119 120 #ifndef PULLDOWN_TEST 121 IP6_EXTHDR_CHECK(m, off, icmp6len,); 122 nd_ns = (struct nd_neighbor_solicit *)((caddr_t)ip6 + off); 123 #else 124 IP6_EXTHDR_GET(nd_ns, struct nd_neighbor_solicit *, m, off, icmp6len); 125 if (nd_ns == NULL) { 126 V_icmp6stat.icp6s_tooshort++; 127 return; 128 } 129 #endif 130 ip6 = mtod(m, struct ip6_hdr *); /* adjust pointer for safety */ 131 taddr6 = nd_ns->nd_ns_target; 132 if (in6_setscope(&taddr6, ifp, NULL) != 0) 133 goto bad; 134 135 if (ip6->ip6_hlim != 255) { 136 nd6log((LOG_ERR, 137 "nd6_ns_input: invalid hlim (%d) from %s to %s on %s\n", 138 ip6->ip6_hlim, ip6_sprintf(ip6bufs, &ip6->ip6_src), 139 ip6_sprintf(ip6bufd, &ip6->ip6_dst), if_name(ifp))); 140 goto bad; 141 } 142 143 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) { 144 /* dst has to be a solicited node multicast address. */ 145 if (daddr6.s6_addr16[0] == IPV6_ADDR_INT16_MLL && 146 /* don't check ifindex portion */ 147 daddr6.s6_addr32[1] == 0 && 148 daddr6.s6_addr32[2] == IPV6_ADDR_INT32_ONE && 149 daddr6.s6_addr8[12] == 0xff) { 150 ; /* good */ 151 } else { 152 nd6log((LOG_INFO, "nd6_ns_input: bad DAD packet " 153 "(wrong ip6 dst)\n")); 154 goto bad; 155 } 156 } else if (!V_nd6_onlink_ns_rfc4861) { 157 struct sockaddr_in6 src_sa6; 158 159 /* 160 * According to recent IETF discussions, it is not a good idea 161 * to accept a NS from an address which would not be deemed 162 * to be a neighbor otherwise. This point is expected to be 163 * clarified in future revisions of the specification. 164 */ 165 bzero(&src_sa6, sizeof(src_sa6)); 166 src_sa6.sin6_family = AF_INET6; 167 src_sa6.sin6_len = sizeof(src_sa6); 168 src_sa6.sin6_addr = saddr6; 169 if (!nd6_is_addr_neighbor(&src_sa6, ifp)) { 170 nd6log((LOG_INFO, "nd6_ns_input: " 171 "NS packet from non-neighbor\n")); 172 goto bad; 173 } 174 } 175 176 if (IN6_IS_ADDR_MULTICAST(&taddr6)) { 177 nd6log((LOG_INFO, "nd6_ns_input: bad NS target (multicast)\n")); 178 goto bad; 179 } 180 181 icmp6len -= sizeof(*nd_ns); 182 nd6_option_init(nd_ns + 1, icmp6len, &ndopts); 183 if (nd6_options(&ndopts) < 0) { 184 nd6log((LOG_INFO, 185 "nd6_ns_input: invalid ND option, ignored\n")); 186 /* nd6_options have incremented stats */ 187 goto freeit; 188 } 189 190 if (ndopts.nd_opts_src_lladdr) { 191 lladdr = (char *)(ndopts.nd_opts_src_lladdr + 1); 192 lladdrlen = ndopts.nd_opts_src_lladdr->nd_opt_len << 3; 193 } 194 195 if (IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_src) && lladdr) { 196 nd6log((LOG_INFO, "nd6_ns_input: bad DAD packet " 197 "(link-layer address option)\n")); 198 goto bad; 199 } 200 201 /* 202 * Attaching target link-layer address to the NA? 203 * (RFC 2461 7.2.4) 204 * 205 * NS IP dst is unicast/anycast MUST NOT add 206 * NS IP dst is solicited-node multicast MUST add 207 * 208 * In implementation, we add target link-layer address by default. 209 * We do not add one in MUST NOT cases. 210 */ 211 if (!IN6_IS_ADDR_MULTICAST(&daddr6)) 212 tlladdr = 0; 213 else 214 tlladdr = 1; 215 216 /* 217 * Target address (taddr6) must be either: 218 * (1) Valid unicast/anycast address for my receiving interface, 219 * (2) Unicast address for which I'm offering proxy service, or 220 * (3) "tentative" address on which DAD is being performed. 221 */ 222 /* (1) and (3) check. */ 223 #ifdef DEV_CARP 224 if (ifp->if_carp) 225 ifa = carp_iamatch6(ifp->if_carp, &taddr6); 226 if (ifa == NULL) 227 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &taddr6); 228 #else 229 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &taddr6); 230 #endif 231 232 /* (2) check. */ 233 if (ifa == NULL) { 234 struct rtentry *rt; 235 struct sockaddr_in6 tsin6; 236 int need_proxy; 237 #ifdef RADIX_MPATH 238 struct route_in6 ro; 239 #endif 240 241 bzero(&tsin6, sizeof tsin6); 242 tsin6.sin6_len = sizeof(struct sockaddr_in6); 243 tsin6.sin6_family = AF_INET6; 244 tsin6.sin6_addr = taddr6; 245 246 #ifdef RADIX_MPATH 247 bzero(&ro, sizeof(ro)); 248 ro.ro_dst = tsin6; 249 rtalloc_mpath((struct route *)&ro, RTF_ANNOUNCE); 250 rt = ro.ro_rt; 251 #else 252 rt = rtalloc1((struct sockaddr *)&tsin6, 0, 0); 253 #endif 254 need_proxy = (rt && (rt->rt_flags & RTF_ANNOUNCE) != 0 && 255 rt->rt_gateway->sa_family == AF_LINK); 256 if (rt) 257 rtfree(rt); 258 if (need_proxy) { 259 /* 260 * proxy NDP for single entry 261 */ 262 ifa = (struct ifaddr *)in6ifa_ifpforlinklocal(ifp, 263 IN6_IFF_NOTREADY|IN6_IFF_ANYCAST); 264 if (ifa) { 265 proxy = 1; 266 proxydl = SDL(rt->rt_gateway); 267 } 268 } 269 } 270 if (ifa == NULL) { 271 /* 272 * We've got an NS packet, and we don't have that adddress 273 * assigned for us. We MUST silently ignore it. 274 * See RFC2461 7.2.3. 275 */ 276 goto freeit; 277 } 278 myaddr6 = *IFA_IN6(ifa); 279 anycast = ((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_ANYCAST; 280 tentative = ((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_TENTATIVE; 281 if (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_DUPLICATED) 282 goto freeit; 283 284 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) { 285 nd6log((LOG_INFO, "nd6_ns_input: lladdrlen mismatch for %s " 286 "(if %d, NS packet %d)\n", 287 ip6_sprintf(ip6bufs, &taddr6), 288 ifp->if_addrlen, lladdrlen - 2)); 289 goto bad; 290 } 291 292 if (IN6_ARE_ADDR_EQUAL(&myaddr6, &saddr6)) { 293 nd6log((LOG_INFO, "nd6_ns_input: duplicate IP6 address %s\n", 294 ip6_sprintf(ip6bufs, &saddr6))); 295 goto freeit; 296 } 297 298 /* 299 * We have neighbor solicitation packet, with target address equals to 300 * one of my tentative address. 301 * 302 * src addr how to process? 303 * --- --- 304 * multicast of course, invalid (rejected in ip6_input) 305 * unicast somebody is doing address resolution -> ignore 306 * unspec dup address detection 307 * 308 * The processing is defined in RFC 2462. 309 */ 310 if (tentative) { 311 /* 312 * If source address is unspecified address, it is for 313 * duplicate address detection. 314 * 315 * If not, the packet is for addess resolution; 316 * silently ignore it. 317 */ 318 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) 319 nd6_dad_ns_input(ifa); 320 321 goto freeit; 322 } 323 324 /* 325 * If the source address is unspecified address, entries must not 326 * be created or updated. 327 * It looks that sender is performing DAD. Output NA toward 328 * all-node multicast address, to tell the sender that I'm using 329 * the address. 330 * S bit ("solicited") must be zero. 331 */ 332 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) { 333 struct in6_addr in6_all; 334 335 in6_all = in6addr_linklocal_allnodes; 336 if (in6_setscope(&in6_all, ifp, NULL) != 0) 337 goto bad; 338 nd6_na_output(ifp, &in6_all, &taddr6, 339 ((anycast || proxy || !tlladdr) ? 0 : ND_NA_FLAG_OVERRIDE) | 340 (V_ip6_forwarding ? ND_NA_FLAG_ROUTER : 0), 341 tlladdr, (struct sockaddr *)proxydl); 342 goto freeit; 343 } 344 345 nd6_cache_lladdr(ifp, &saddr6, lladdr, lladdrlen, 346 ND_NEIGHBOR_SOLICIT, 0); 347 348 nd6_na_output(ifp, &saddr6, &taddr6, 349 ((anycast || proxy || !tlladdr) ? 0 : ND_NA_FLAG_OVERRIDE) | 350 (V_ip6_forwarding ? ND_NA_FLAG_ROUTER : 0) | ND_NA_FLAG_SOLICITED, 351 tlladdr, (struct sockaddr *)proxydl); 352 freeit: 353 m_freem(m); 354 return; 355 356 bad: 357 nd6log((LOG_ERR, "nd6_ns_input: src=%s\n", 358 ip6_sprintf(ip6bufs, &saddr6))); 359 nd6log((LOG_ERR, "nd6_ns_input: dst=%s\n", 360 ip6_sprintf(ip6bufs, &daddr6))); 361 nd6log((LOG_ERR, "nd6_ns_input: tgt=%s\n", 362 ip6_sprintf(ip6bufs, &taddr6))); 363 V_icmp6stat.icp6s_badns++; 364 m_freem(m); 365 } 366 367 /* 368 * Output a Neighbor Solicitation Message. Caller specifies: 369 * - ICMP6 header source IP6 address 370 * - ND6 header target IP6 address 371 * - ND6 header source datalink address 372 * 373 * Based on RFC 2461 374 * Based on RFC 2462 (duplicate address detection) 375 * 376 * ln - for source address determination 377 * dad - duplicate address detection 378 */ 379 void 380 nd6_ns_output(struct ifnet *ifp, const struct in6_addr *daddr6, 381 const struct in6_addr *taddr6, struct llinfo_nd6 *ln, int dad) 382 { 383 INIT_VNET_INET6(ifp->if_vnet); 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 /* 455 * RFC2461 7.2.2: 456 * "If the source address of the packet prompting the 457 * solicitation is the same as one of the addresses assigned 458 * to the outgoing interface, that address SHOULD be placed 459 * in the IP Source Address of the outgoing solicitation. 460 * Otherwise, any one of the addresses assigned to the 461 * interface should be used." 462 * 463 * We use the source address for the prompting packet 464 * (saddr6), if: 465 * - saddr6 is given from the caller (by giving "ln"), and 466 * - saddr6 belongs to the outgoing interface. 467 * Otherwise, we perform the source address selection as usual. 468 */ 469 struct ip6_hdr *hip6; /* hold ip6 */ 470 struct in6_addr *hsrc = NULL; 471 472 if (ln && ln->ln_hold) { 473 /* 474 * assuming every packet in ln_hold has the same IP 475 * header 476 */ 477 hip6 = mtod(ln->ln_hold, struct ip6_hdr *); 478 /* XXX pullup? */ 479 if (sizeof(*hip6) < ln->ln_hold->m_len) 480 hsrc = &hip6->ip6_src; 481 else 482 hsrc = NULL; 483 } 484 if (hsrc && in6ifa_ifpwithaddr(ifp, hsrc)) 485 src = hsrc; 486 else { 487 int error; 488 struct sockaddr_in6 dst_sa; 489 490 bzero(&dst_sa, sizeof(dst_sa)); 491 dst_sa.sin6_family = AF_INET6; 492 dst_sa.sin6_len = sizeof(dst_sa); 493 dst_sa.sin6_addr = ip6->ip6_dst; 494 495 src = in6_selectsrc(&dst_sa, NULL, 496 NULL, &ro, NULL, NULL, &error); 497 if (src == NULL) { 498 char ip6buf[INET6_ADDRSTRLEN]; 499 nd6log((LOG_DEBUG, 500 "nd6_ns_output: source can't be " 501 "determined: dst=%s, error=%d\n", 502 ip6_sprintf(ip6buf, &dst_sa.sin6_addr), 503 error)); 504 goto bad; 505 } 506 } 507 } else { 508 /* 509 * Source address for DAD packet must always be IPv6 510 * unspecified address. (0::0) 511 * We actually don't have to 0-clear the address (we did it 512 * above), but we do so here explicitly to make the intention 513 * clearer. 514 */ 515 bzero(&src_in, sizeof(src_in)); 516 src = &src_in; 517 } 518 ip6->ip6_src = *src; 519 nd_ns = (struct nd_neighbor_solicit *)(ip6 + 1); 520 nd_ns->nd_ns_type = ND_NEIGHBOR_SOLICIT; 521 nd_ns->nd_ns_code = 0; 522 nd_ns->nd_ns_reserved = 0; 523 nd_ns->nd_ns_target = *taddr6; 524 in6_clearscope(&nd_ns->nd_ns_target); /* XXX */ 525 526 /* 527 * Add source link-layer address option. 528 * 529 * spec implementation 530 * --- --- 531 * DAD packet MUST NOT do not add the option 532 * there's no link layer address: 533 * impossible do not add the option 534 * there's link layer address: 535 * Multicast NS MUST add one add the option 536 * Unicast NS SHOULD add one add the option 537 */ 538 if (!dad && (mac = nd6_ifptomac(ifp))) { 539 int optlen = sizeof(struct nd_opt_hdr) + ifp->if_addrlen; 540 struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)(nd_ns + 1); 541 /* 8 byte alignments... */ 542 optlen = (optlen + 7) & ~7; 543 544 m->m_pkthdr.len += optlen; 545 m->m_len += optlen; 546 icmp6len += optlen; 547 bzero((caddr_t)nd_opt, optlen); 548 nd_opt->nd_opt_type = ND_OPT_SOURCE_LINKADDR; 549 nd_opt->nd_opt_len = optlen >> 3; 550 bcopy(mac, (caddr_t)(nd_opt + 1), ifp->if_addrlen); 551 } 552 553 ip6->ip6_plen = htons((u_short)icmp6len); 554 nd_ns->nd_ns_cksum = 0; 555 nd_ns->nd_ns_cksum = 556 in6_cksum(m, IPPROTO_ICMPV6, sizeof(*ip6), icmp6len); 557 558 ip6_output(m, NULL, &ro, dad ? IPV6_UNSPECSRC : 0, &im6o, NULL, NULL); 559 icmp6_ifstat_inc(ifp, ifs6_out_msg); 560 icmp6_ifstat_inc(ifp, ifs6_out_neighborsolicit); 561 V_icmp6stat.icp6s_outhist[ND_NEIGHBOR_SOLICIT]++; 562 563 if (ro.ro_rt) { /* we don't cache this route. */ 564 RTFREE(ro.ro_rt); 565 } 566 return; 567 568 bad: 569 if (ro.ro_rt) { 570 RTFREE(ro.ro_rt); 571 } 572 m_freem(m); 573 return; 574 } 575 576 /* 577 * Neighbor advertisement input handling. 578 * 579 * Based on RFC 2461 580 * Based on RFC 2462 (duplicate address detection) 581 * 582 * the following items are not implemented yet: 583 * - proxy advertisement delay rule (RFC2461 7.2.8, last paragraph, SHOULD) 584 * - anycast advertisement delay rule (RFC2461 7.2.7, SHOULD) 585 */ 586 void 587 nd6_na_input(struct mbuf *m, int off, int icmp6len) 588 { 589 INIT_VNET_INET6(curvnet); 590 struct ifnet *ifp = m->m_pkthdr.rcvif; 591 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 592 struct nd_neighbor_advert *nd_na; 593 struct in6_addr daddr6 = ip6->ip6_dst; 594 struct in6_addr taddr6; 595 int flags; 596 int is_router; 597 int is_solicited; 598 int is_override; 599 char *lladdr = NULL; 600 int lladdrlen = 0; 601 struct ifaddr *ifa; 602 struct llinfo_nd6 *ln; 603 struct rtentry *rt; 604 struct sockaddr_dl *sdl; 605 union nd_opts ndopts; 606 char ip6bufs[INET6_ADDRSTRLEN], ip6bufd[INET6_ADDRSTRLEN]; 607 608 if (ip6->ip6_hlim != 255) { 609 nd6log((LOG_ERR, 610 "nd6_na_input: invalid hlim (%d) from %s to %s on %s\n", 611 ip6->ip6_hlim, ip6_sprintf(ip6bufs, &ip6->ip6_src), 612 ip6_sprintf(ip6bufd, &ip6->ip6_dst), if_name(ifp))); 613 goto bad; 614 } 615 616 #ifndef PULLDOWN_TEST 617 IP6_EXTHDR_CHECK(m, off, icmp6len,); 618 nd_na = (struct nd_neighbor_advert *)((caddr_t)ip6 + off); 619 #else 620 IP6_EXTHDR_GET(nd_na, struct nd_neighbor_advert *, m, off, icmp6len); 621 if (nd_na == NULL) { 622 V_icmp6stat.icp6s_tooshort++; 623 return; 624 } 625 #endif 626 627 flags = nd_na->nd_na_flags_reserved; 628 is_router = ((flags & ND_NA_FLAG_ROUTER) != 0); 629 is_solicited = ((flags & ND_NA_FLAG_SOLICITED) != 0); 630 is_override = ((flags & ND_NA_FLAG_OVERRIDE) != 0); 631 632 taddr6 = nd_na->nd_na_target; 633 if (in6_setscope(&taddr6, ifp, NULL)) 634 goto bad; /* XXX: impossible */ 635 636 if (IN6_IS_ADDR_MULTICAST(&taddr6)) { 637 nd6log((LOG_ERR, 638 "nd6_na_input: invalid target address %s\n", 639 ip6_sprintf(ip6bufs, &taddr6))); 640 goto bad; 641 } 642 if (IN6_IS_ADDR_MULTICAST(&daddr6)) 643 if (is_solicited) { 644 nd6log((LOG_ERR, 645 "nd6_na_input: a solicited adv is multicasted\n")); 646 goto bad; 647 } 648 649 icmp6len -= sizeof(*nd_na); 650 nd6_option_init(nd_na + 1, icmp6len, &ndopts); 651 if (nd6_options(&ndopts) < 0) { 652 nd6log((LOG_INFO, 653 "nd6_na_input: invalid ND option, ignored\n")); 654 /* nd6_options have incremented stats */ 655 goto freeit; 656 } 657 658 if (ndopts.nd_opts_tgt_lladdr) { 659 lladdr = (char *)(ndopts.nd_opts_tgt_lladdr + 1); 660 lladdrlen = ndopts.nd_opts_tgt_lladdr->nd_opt_len << 3; 661 } 662 663 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &taddr6); 664 665 /* 666 * Target address matches one of my interface address. 667 * 668 * If my address is tentative, this means that there's somebody 669 * already using the same address as mine. This indicates DAD failure. 670 * This is defined in RFC 2462. 671 * 672 * Otherwise, process as defined in RFC 2461. 673 */ 674 if (ifa 675 && (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_TENTATIVE)) { 676 nd6_dad_na_input(ifa); 677 goto freeit; 678 } 679 680 /* Just for safety, maybe unnecessary. */ 681 if (ifa) { 682 log(LOG_ERR, 683 "nd6_na_input: duplicate IP6 address %s\n", 684 ip6_sprintf(ip6bufs, &taddr6)); 685 goto freeit; 686 } 687 688 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) { 689 nd6log((LOG_INFO, "nd6_na_input: lladdrlen mismatch for %s " 690 "(if %d, NA packet %d)\n", ip6_sprintf(ip6bufs, &taddr6), 691 ifp->if_addrlen, lladdrlen - 2)); 692 goto bad; 693 } 694 695 /* 696 * If no neighbor cache entry is found, NA SHOULD silently be 697 * discarded. 698 */ 699 rt = nd6_lookup(&taddr6, 0, ifp); 700 if ((rt == NULL) || 701 ((ln = (struct llinfo_nd6 *)rt->rt_llinfo) == NULL) || 702 ((sdl = SDL(rt->rt_gateway)) == NULL)) 703 goto freeit; 704 705 if (ln->ln_state == ND6_LLINFO_INCOMPLETE) { 706 /* 707 * If the link-layer has address, and no lladdr option came, 708 * discard the packet. 709 */ 710 if (ifp->if_addrlen && lladdr == NULL) 711 goto freeit; 712 713 /* 714 * Record link-layer address, and update the state. 715 */ 716 sdl->sdl_alen = ifp->if_addrlen; 717 bcopy(lladdr, LLADDR(sdl), ifp->if_addrlen); 718 if (is_solicited) { 719 ln->ln_state = ND6_LLINFO_REACHABLE; 720 ln->ln_byhint = 0; 721 if (!ND6_LLINFO_PERMANENT(ln)) { 722 nd6_llinfo_settimer(ln, 723 (long)ND_IFINFO(rt->rt_ifp)->reachable * hz); 724 } 725 } else { 726 ln->ln_state = ND6_LLINFO_STALE; 727 nd6_llinfo_settimer(ln, (long)V_nd6_gctimer * hz); 728 } 729 if ((ln->ln_router = is_router) != 0) { 730 /* 731 * This means a router's state has changed from 732 * non-reachable to probably reachable, and might 733 * affect the status of associated prefixes.. 734 */ 735 pfxlist_onlink_check(); 736 } 737 } else { 738 int llchange; 739 740 /* 741 * Check if the link-layer address has changed or not. 742 */ 743 if (lladdr == NULL) 744 llchange = 0; 745 else { 746 if (sdl->sdl_alen) { 747 if (bcmp(lladdr, LLADDR(sdl), ifp->if_addrlen)) 748 llchange = 1; 749 else 750 llchange = 0; 751 } else 752 llchange = 1; 753 } 754 755 /* 756 * This is VERY complex. Look at it with care. 757 * 758 * override solicit lladdr llchange action 759 * (L: record lladdr) 760 * 761 * 0 0 n -- (2c) 762 * 0 0 y n (2b) L 763 * 0 0 y y (1) REACHABLE->STALE 764 * 0 1 n -- (2c) *->REACHABLE 765 * 0 1 y n (2b) L *->REACHABLE 766 * 0 1 y y (1) REACHABLE->STALE 767 * 1 0 n -- (2a) 768 * 1 0 y n (2a) L 769 * 1 0 y y (2a) L *->STALE 770 * 1 1 n -- (2a) *->REACHABLE 771 * 1 1 y n (2a) L *->REACHABLE 772 * 1 1 y y (2a) L *->REACHABLE 773 */ 774 if (!is_override && (lladdr != NULL && llchange)) { /* (1) */ 775 /* 776 * If state is REACHABLE, make it STALE. 777 * no other updates should be done. 778 */ 779 if (ln->ln_state == ND6_LLINFO_REACHABLE) { 780 ln->ln_state = ND6_LLINFO_STALE; 781 nd6_llinfo_settimer(ln, (long)V_nd6_gctimer * hz); 782 } 783 goto freeit; 784 } else if (is_override /* (2a) */ 785 || (!is_override && (lladdr != NULL && !llchange)) /* (2b) */ 786 || lladdr == NULL) { /* (2c) */ 787 /* 788 * Update link-local address, if any. 789 */ 790 if (lladdr != NULL) { 791 sdl->sdl_alen = ifp->if_addrlen; 792 bcopy(lladdr, LLADDR(sdl), ifp->if_addrlen); 793 } 794 795 /* 796 * If solicited, make the state REACHABLE. 797 * If not solicited and the link-layer address was 798 * changed, make it STALE. 799 */ 800 if (is_solicited) { 801 ln->ln_state = ND6_LLINFO_REACHABLE; 802 ln->ln_byhint = 0; 803 if (!ND6_LLINFO_PERMANENT(ln)) { 804 nd6_llinfo_settimer(ln, 805 (long)ND_IFINFO(ifp)->reachable * hz); 806 } 807 } else { 808 if (lladdr != NULL && llchange) { 809 ln->ln_state = ND6_LLINFO_STALE; 810 nd6_llinfo_settimer(ln, 811 (long)V_nd6_gctimer * hz); 812 } 813 } 814 } 815 816 if (ln->ln_router && !is_router) { 817 /* 818 * The peer dropped the router flag. 819 * Remove the sender from the Default Router List and 820 * update the Destination Cache entries. 821 */ 822 struct nd_defrouter *dr; 823 struct in6_addr *in6; 824 int s; 825 826 in6 = &((struct sockaddr_in6 *)rt_key(rt))->sin6_addr; 827 828 /* 829 * Lock to protect the default router list. 830 * XXX: this might be unnecessary, since this function 831 * is only called under the network software interrupt 832 * context. However, we keep it just for safety. 833 */ 834 s = splnet(); 835 dr = defrouter_lookup(in6, ifp); 836 if (dr) 837 defrtrlist_del(dr); 838 else if (!V_ip6_forwarding) { 839 /* 840 * Even if the neighbor is not in the default 841 * router list, the neighbor may be used 842 * as a next hop for some destinations 843 * (e.g. redirect case). So we must 844 * call rt6_flush explicitly. 845 */ 846 rt6_flush(&ip6->ip6_src, ifp); 847 } 848 splx(s); 849 } 850 ln->ln_router = is_router; 851 } 852 rt->rt_flags &= ~RTF_REJECT; 853 ln->ln_asked = 0; 854 if (ln->ln_hold) { 855 struct mbuf *m_hold, *m_hold_next; 856 857 /* 858 * reset the ln_hold in advance, to explicitly 859 * prevent a ln_hold lookup in nd6_output() 860 * (wouldn't happen, though...) 861 */ 862 for (m_hold = ln->ln_hold; 863 m_hold; m_hold = m_hold_next) { 864 m_hold_next = m_hold->m_nextpkt; 865 m_hold->m_nextpkt = NULL; 866 /* 867 * we assume ifp is not a loopback here, so just set 868 * the 2nd argument as the 1st one. 869 */ 870 nd6_output(ifp, ifp, m_hold, 871 (struct sockaddr_in6 *)rt_key(rt), rt); 872 } 873 ln->ln_hold = NULL; 874 } 875 876 freeit: 877 m_freem(m); 878 return; 879 880 bad: 881 V_icmp6stat.icp6s_badna++; 882 m_freem(m); 883 } 884 885 /* 886 * Neighbor advertisement output handling. 887 * 888 * Based on RFC 2461 889 * 890 * the following items are not implemented yet: 891 * - proxy advertisement delay rule (RFC2461 7.2.8, last paragraph, SHOULD) 892 * - anycast advertisement delay rule (RFC2461 7.2.7, SHOULD) 893 * 894 * tlladdr - 1 if include target link-layer address 895 * sdl0 - sockaddr_dl (= proxy NA) or NULL 896 */ 897 void 898 nd6_na_output(struct ifnet *ifp, const struct in6_addr *daddr6_0, 899 const struct in6_addr *taddr6, u_long flags, int tlladdr, 900 struct sockaddr *sdl0) 901 { 902 INIT_VNET_INET6(ifp->if_vnet); 903 struct mbuf *m; 904 struct ip6_hdr *ip6; 905 struct nd_neighbor_advert *nd_na; 906 struct ip6_moptions im6o; 907 struct in6_addr *src, daddr6; 908 struct sockaddr_in6 dst_sa; 909 int icmp6len, maxlen, error; 910 caddr_t mac = NULL; 911 struct route_in6 ro; 912 913 bzero(&ro, sizeof(ro)); 914 915 daddr6 = *daddr6_0; /* make a local copy for modification */ 916 917 /* estimate the size of message */ 918 maxlen = sizeof(*ip6) + sizeof(*nd_na); 919 maxlen += (sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7; 920 if (max_linkhdr + maxlen >= MCLBYTES) { 921 #ifdef DIAGNOSTIC 922 printf("nd6_na_output: max_linkhdr + maxlen >= MCLBYTES " 923 "(%d + %d > %d)\n", max_linkhdr, maxlen, MCLBYTES); 924 #endif 925 return; 926 } 927 928 MGETHDR(m, M_DONTWAIT, MT_DATA); 929 if (m && max_linkhdr + maxlen >= MHLEN) { 930 MCLGET(m, M_DONTWAIT); 931 if ((m->m_flags & M_EXT) == 0) { 932 m_free(m); 933 m = NULL; 934 } 935 } 936 if (m == NULL) 937 return; 938 m->m_pkthdr.rcvif = NULL; 939 940 if (IN6_IS_ADDR_MULTICAST(&daddr6)) { 941 m->m_flags |= M_MCAST; 942 im6o.im6o_multicast_ifp = ifp; 943 im6o.im6o_multicast_hlim = 255; 944 im6o.im6o_multicast_loop = 0; 945 } 946 947 icmp6len = sizeof(*nd_na); 948 m->m_pkthdr.len = m->m_len = sizeof(struct ip6_hdr) + icmp6len; 949 m->m_data += max_linkhdr; /* or MH_ALIGN() equivalent? */ 950 951 /* fill neighbor advertisement packet */ 952 ip6 = mtod(m, struct ip6_hdr *); 953 ip6->ip6_flow = 0; 954 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 955 ip6->ip6_vfc |= IPV6_VERSION; 956 ip6->ip6_nxt = IPPROTO_ICMPV6; 957 ip6->ip6_hlim = 255; 958 if (IN6_IS_ADDR_UNSPECIFIED(&daddr6)) { 959 /* reply to DAD */ 960 daddr6.s6_addr16[0] = IPV6_ADDR_INT16_MLL; 961 daddr6.s6_addr16[1] = 0; 962 daddr6.s6_addr32[1] = 0; 963 daddr6.s6_addr32[2] = 0; 964 daddr6.s6_addr32[3] = IPV6_ADDR_INT32_ONE; 965 if (in6_setscope(&daddr6, ifp, NULL)) 966 goto bad; 967 968 flags &= ~ND_NA_FLAG_SOLICITED; 969 } 970 ip6->ip6_dst = daddr6; 971 bzero(&dst_sa, sizeof(struct sockaddr_in6)); 972 dst_sa.sin6_family = AF_INET6; 973 dst_sa.sin6_len = sizeof(struct sockaddr_in6); 974 dst_sa.sin6_addr = daddr6; 975 976 /* 977 * Select a source whose scope is the same as that of the dest. 978 */ 979 bcopy(&dst_sa, &ro.ro_dst, sizeof(dst_sa)); 980 src = in6_selectsrc(&dst_sa, NULL, NULL, &ro, NULL, NULL, &error); 981 if (src == NULL) { 982 char ip6buf[INET6_ADDRSTRLEN]; 983 nd6log((LOG_DEBUG, "nd6_na_output: source can't be " 984 "determined: dst=%s, error=%d\n", 985 ip6_sprintf(ip6buf, &dst_sa.sin6_addr), error)); 986 goto bad; 987 } 988 ip6->ip6_src = *src; 989 nd_na = (struct nd_neighbor_advert *)(ip6 + 1); 990 nd_na->nd_na_type = ND_NEIGHBOR_ADVERT; 991 nd_na->nd_na_code = 0; 992 nd_na->nd_na_target = *taddr6; 993 in6_clearscope(&nd_na->nd_na_target); /* XXX */ 994 995 /* 996 * "tlladdr" indicates NS's condition for adding tlladdr or not. 997 * see nd6_ns_input() for details. 998 * Basically, if NS packet is sent to unicast/anycast addr, 999 * target lladdr option SHOULD NOT be included. 1000 */ 1001 if (tlladdr) { 1002 /* 1003 * sdl0 != NULL indicates proxy NA. If we do proxy, use 1004 * lladdr in sdl0. If we are not proxying (sending NA for 1005 * my address) use lladdr configured for the interface. 1006 */ 1007 if (sdl0 == NULL) { 1008 #ifdef DEV_CARP 1009 if (ifp->if_carp) 1010 mac = carp_macmatch6(ifp->if_carp, m, taddr6); 1011 if (mac == NULL) 1012 mac = nd6_ifptomac(ifp); 1013 #else 1014 mac = nd6_ifptomac(ifp); 1015 #endif 1016 } else if (sdl0->sa_family == AF_LINK) { 1017 struct sockaddr_dl *sdl; 1018 sdl = (struct sockaddr_dl *)sdl0; 1019 if (sdl->sdl_alen == ifp->if_addrlen) 1020 mac = LLADDR(sdl); 1021 } 1022 } 1023 if (tlladdr && mac) { 1024 int optlen = sizeof(struct nd_opt_hdr) + ifp->if_addrlen; 1025 struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)(nd_na + 1); 1026 1027 /* roundup to 8 bytes alignment! */ 1028 optlen = (optlen + 7) & ~7; 1029 1030 m->m_pkthdr.len += optlen; 1031 m->m_len += optlen; 1032 icmp6len += optlen; 1033 bzero((caddr_t)nd_opt, optlen); 1034 nd_opt->nd_opt_type = ND_OPT_TARGET_LINKADDR; 1035 nd_opt->nd_opt_len = optlen >> 3; 1036 bcopy(mac, (caddr_t)(nd_opt + 1), ifp->if_addrlen); 1037 } else 1038 flags &= ~ND_NA_FLAG_OVERRIDE; 1039 1040 ip6->ip6_plen = htons((u_short)icmp6len); 1041 nd_na->nd_na_flags_reserved = flags; 1042 nd_na->nd_na_cksum = 0; 1043 nd_na->nd_na_cksum = 1044 in6_cksum(m, IPPROTO_ICMPV6, sizeof(struct ip6_hdr), icmp6len); 1045 1046 ip6_output(m, NULL, &ro, 0, &im6o, NULL, NULL); 1047 icmp6_ifstat_inc(ifp, ifs6_out_msg); 1048 icmp6_ifstat_inc(ifp, ifs6_out_neighboradvert); 1049 V_icmp6stat.icp6s_outhist[ND_NEIGHBOR_ADVERT]++; 1050 1051 if (ro.ro_rt) { /* we don't cache this route. */ 1052 RTFREE(ro.ro_rt); 1053 } 1054 return; 1055 1056 bad: 1057 if (ro.ro_rt) { 1058 RTFREE(ro.ro_rt); 1059 } 1060 m_freem(m); 1061 return; 1062 } 1063 1064 caddr_t 1065 nd6_ifptomac(struct ifnet *ifp) 1066 { 1067 switch (ifp->if_type) { 1068 case IFT_ARCNET: 1069 case IFT_ETHER: 1070 case IFT_FDDI: 1071 case IFT_IEEE1394: 1072 #ifdef IFT_L2VLAN 1073 case IFT_L2VLAN: 1074 #endif 1075 #ifdef IFT_IEEE80211 1076 case IFT_IEEE80211: 1077 #endif 1078 #ifdef IFT_CARP 1079 case IFT_CARP: 1080 #endif 1081 case IFT_BRIDGE: 1082 case IFT_ISO88025: 1083 return IF_LLADDR(ifp); 1084 default: 1085 return NULL; 1086 } 1087 } 1088 1089 TAILQ_HEAD(dadq_head, dadq); 1090 struct dadq { 1091 TAILQ_ENTRY(dadq) dad_list; 1092 struct ifaddr *dad_ifa; 1093 int dad_count; /* max NS to send */ 1094 int dad_ns_tcount; /* # of trials to send NS */ 1095 int dad_ns_ocount; /* NS sent so far */ 1096 int dad_ns_icount; 1097 int dad_na_icount; 1098 struct callout dad_timer_ch; 1099 }; 1100 1101 #ifdef VIMAGE_GLOBALS 1102 static struct dadq_head dadq; 1103 int dad_init; 1104 #endif 1105 1106 static struct dadq * 1107 nd6_dad_find(struct ifaddr *ifa) 1108 { 1109 INIT_VNET_INET6(curvnet); 1110 struct dadq *dp; 1111 1112 for (dp = V_dadq.tqh_first; dp; dp = dp->dad_list.tqe_next) { 1113 if (dp->dad_ifa == ifa) 1114 return dp; 1115 } 1116 return NULL; 1117 } 1118 1119 static void 1120 nd6_dad_starttimer(struct dadq *dp, int ticks) 1121 { 1122 1123 callout_reset(&dp->dad_timer_ch, ticks, 1124 (void (*)(void *))nd6_dad_timer, (void *)dp->dad_ifa); 1125 } 1126 1127 static void 1128 nd6_dad_stoptimer(struct dadq *dp) 1129 { 1130 1131 callout_stop(&dp->dad_timer_ch); 1132 } 1133 1134 /* 1135 * Start Duplicate Address Detection (DAD) for specified interface address. 1136 */ 1137 void 1138 nd6_dad_start(struct ifaddr *ifa, int delay) 1139 { 1140 INIT_VNET_INET6(curvnet); 1141 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1142 struct dadq *dp; 1143 char ip6buf[INET6_ADDRSTRLEN]; 1144 1145 if (!V_dad_init) { 1146 TAILQ_INIT(&V_dadq); 1147 V_dad_init++; 1148 } 1149 1150 /* 1151 * If we don't need DAD, don't do it. 1152 * There are several cases: 1153 * - DAD is disabled (ip6_dad_count == 0) 1154 * - the interface address is anycast 1155 */ 1156 if (!(ia->ia6_flags & IN6_IFF_TENTATIVE)) { 1157 log(LOG_DEBUG, 1158 "nd6_dad_start: called with non-tentative address " 1159 "%s(%s)\n", 1160 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr), 1161 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1162 return; 1163 } 1164 if (ia->ia6_flags & IN6_IFF_ANYCAST) { 1165 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1166 return; 1167 } 1168 if (!V_ip6_dad_count) { 1169 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1170 return; 1171 } 1172 if (ifa->ifa_ifp == NULL) 1173 panic("nd6_dad_start: ifa->ifa_ifp == NULL"); 1174 if (!(ifa->ifa_ifp->if_flags & IFF_UP)) { 1175 return; 1176 } 1177 if (nd6_dad_find(ifa) != NULL) { 1178 /* DAD already in progress */ 1179 return; 1180 } 1181 1182 dp = malloc(sizeof(*dp), M_IP6NDP, M_NOWAIT); 1183 if (dp == NULL) { 1184 log(LOG_ERR, "nd6_dad_start: memory allocation failed for " 1185 "%s(%s)\n", 1186 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr), 1187 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1188 return; 1189 } 1190 bzero(dp, sizeof(*dp)); 1191 callout_init(&dp->dad_timer_ch, 0); 1192 TAILQ_INSERT_TAIL(&V_dadq, (struct dadq *)dp, dad_list); 1193 1194 nd6log((LOG_DEBUG, "%s: starting DAD for %s\n", if_name(ifa->ifa_ifp), 1195 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr))); 1196 1197 /* 1198 * Send NS packet for DAD, ip6_dad_count times. 1199 * Note that we must delay the first transmission, if this is the 1200 * first packet to be sent from the interface after interface 1201 * (re)initialization. 1202 */ 1203 dp->dad_ifa = ifa; 1204 IFAREF(ifa); /* just for safety */ 1205 dp->dad_count = V_ip6_dad_count; 1206 dp->dad_ns_icount = dp->dad_na_icount = 0; 1207 dp->dad_ns_ocount = dp->dad_ns_tcount = 0; 1208 if (delay == 0) { 1209 nd6_dad_ns_output(dp, ifa); 1210 nd6_dad_starttimer(dp, 1211 (long)ND_IFINFO(ifa->ifa_ifp)->retrans * hz / 1000); 1212 } else { 1213 nd6_dad_starttimer(dp, delay); 1214 } 1215 } 1216 1217 /* 1218 * terminate DAD unconditionally. used for address removals. 1219 */ 1220 void 1221 nd6_dad_stop(struct ifaddr *ifa) 1222 { 1223 INIT_VNET_INET6(curvnet); 1224 struct dadq *dp; 1225 1226 if (!V_dad_init) 1227 return; 1228 dp = nd6_dad_find(ifa); 1229 if (!dp) { 1230 /* DAD wasn't started yet */ 1231 return; 1232 } 1233 1234 nd6_dad_stoptimer(dp); 1235 1236 TAILQ_REMOVE(&V_dadq, (struct dadq *)dp, dad_list); 1237 free(dp, M_IP6NDP); 1238 dp = NULL; 1239 IFAFREE(ifa); 1240 } 1241 1242 static void 1243 nd6_dad_timer(struct ifaddr *ifa) 1244 { 1245 CURVNET_SET(dp->dad_vnet); 1246 INIT_VNET_INET6(curvnet); 1247 int s; 1248 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1249 struct dadq *dp; 1250 char ip6buf[INET6_ADDRSTRLEN]; 1251 1252 s = splnet(); /* XXX */ 1253 1254 /* Sanity check */ 1255 if (ia == NULL) { 1256 log(LOG_ERR, "nd6_dad_timer: called with null parameter\n"); 1257 goto done; 1258 } 1259 dp = nd6_dad_find(ifa); 1260 if (dp == NULL) { 1261 log(LOG_ERR, "nd6_dad_timer: DAD structure not found\n"); 1262 goto done; 1263 } 1264 if (ia->ia6_flags & IN6_IFF_DUPLICATED) { 1265 log(LOG_ERR, "nd6_dad_timer: called with duplicated address " 1266 "%s(%s)\n", 1267 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr), 1268 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1269 goto done; 1270 } 1271 if ((ia->ia6_flags & IN6_IFF_TENTATIVE) == 0) { 1272 log(LOG_ERR, "nd6_dad_timer: called with non-tentative address " 1273 "%s(%s)\n", 1274 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr), 1275 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1276 goto done; 1277 } 1278 1279 /* timeouted with IFF_{RUNNING,UP} check */ 1280 if (dp->dad_ns_tcount > V_dad_maxtry) { 1281 nd6log((LOG_INFO, "%s: could not run DAD, driver problem?\n", 1282 if_name(ifa->ifa_ifp))); 1283 1284 TAILQ_REMOVE(&V_dadq, (struct dadq *)dp, dad_list); 1285 free(dp, M_IP6NDP); 1286 dp = NULL; 1287 IFAFREE(ifa); 1288 goto done; 1289 } 1290 1291 /* Need more checks? */ 1292 if (dp->dad_ns_ocount < dp->dad_count) { 1293 /* 1294 * We have more NS to go. Send NS packet for DAD. 1295 */ 1296 nd6_dad_ns_output(dp, ifa); 1297 nd6_dad_starttimer(dp, 1298 (long)ND_IFINFO(ifa->ifa_ifp)->retrans * hz / 1000); 1299 } else { 1300 /* 1301 * We have transmitted sufficient number of DAD packets. 1302 * See what we've got. 1303 */ 1304 int duplicate; 1305 1306 duplicate = 0; 1307 1308 if (dp->dad_na_icount) { 1309 /* 1310 * the check is in nd6_dad_na_input(), 1311 * but just in case 1312 */ 1313 duplicate++; 1314 } 1315 1316 if (dp->dad_ns_icount) { 1317 /* We've seen NS, means DAD has failed. */ 1318 duplicate++; 1319 } 1320 1321 if (duplicate) { 1322 /* (*dp) will be freed in nd6_dad_duplicated() */ 1323 dp = NULL; 1324 nd6_dad_duplicated(ifa); 1325 } else { 1326 /* 1327 * We are done with DAD. No NA came, no NS came. 1328 * No duplicate address found. 1329 */ 1330 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1331 1332 nd6log((LOG_DEBUG, 1333 "%s: DAD complete for %s - no duplicates found\n", 1334 if_name(ifa->ifa_ifp), 1335 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr))); 1336 1337 TAILQ_REMOVE(&V_dadq, (struct dadq *)dp, dad_list); 1338 free(dp, M_IP6NDP); 1339 dp = NULL; 1340 IFAFREE(ifa); 1341 } 1342 } 1343 1344 done: 1345 splx(s); 1346 CURVNET_RESTORE(); 1347 } 1348 1349 void 1350 nd6_dad_duplicated(struct ifaddr *ifa) 1351 { 1352 INIT_VNET_INET6(curvnet); 1353 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1354 struct ifnet *ifp; 1355 struct dadq *dp; 1356 char ip6buf[INET6_ADDRSTRLEN]; 1357 1358 dp = nd6_dad_find(ifa); 1359 if (dp == NULL) { 1360 log(LOG_ERR, "nd6_dad_duplicated: DAD structure not found\n"); 1361 return; 1362 } 1363 1364 log(LOG_ERR, "%s: DAD detected duplicate IPv6 address %s: " 1365 "NS in/out=%d/%d, NA in=%d\n", 1366 if_name(ifa->ifa_ifp), ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr), 1367 dp->dad_ns_icount, dp->dad_ns_ocount, dp->dad_na_icount); 1368 1369 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1370 ia->ia6_flags |= IN6_IFF_DUPLICATED; 1371 1372 /* We are done with DAD, with duplicate address found. (failure) */ 1373 nd6_dad_stoptimer(dp); 1374 1375 ifp = ifa->ifa_ifp; 1376 log(LOG_ERR, "%s: DAD complete for %s - duplicate found\n", 1377 if_name(ifp), ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr)); 1378 log(LOG_ERR, "%s: manual intervention required\n", 1379 if_name(ifp)); 1380 1381 /* 1382 * If the address is a link-local address formed from an interface 1383 * identifier based on the hardware address which is supposed to be 1384 * uniquely assigned (e.g., EUI-64 for an Ethernet interface), IP 1385 * operation on the interface SHOULD be disabled. 1386 * [rfc2462bis-03 Section 5.4.5] 1387 */ 1388 if (IN6_IS_ADDR_LINKLOCAL(&ia->ia_addr.sin6_addr)) { 1389 struct in6_addr in6; 1390 1391 /* 1392 * To avoid over-reaction, we only apply this logic when we are 1393 * very sure that hardware addresses are supposed to be unique. 1394 */ 1395 switch (ifp->if_type) { 1396 case IFT_ETHER: 1397 case IFT_FDDI: 1398 case IFT_ATM: 1399 case IFT_IEEE1394: 1400 #ifdef IFT_IEEE80211 1401 case IFT_IEEE80211: 1402 #endif 1403 in6 = ia->ia_addr.sin6_addr; 1404 if (in6_get_hw_ifid(ifp, &in6) == 0 && 1405 IN6_ARE_ADDR_EQUAL(&ia->ia_addr.sin6_addr, &in6)) { 1406 ND_IFINFO(ifp)->flags |= ND6_IFF_IFDISABLED; 1407 log(LOG_ERR, "%s: possible hardware address " 1408 "duplication detected, disable IPv6\n", 1409 if_name(ifp)); 1410 } 1411 break; 1412 } 1413 } 1414 1415 TAILQ_REMOVE(&V_dadq, (struct dadq *)dp, dad_list); 1416 free(dp, M_IP6NDP); 1417 dp = NULL; 1418 IFAFREE(ifa); 1419 } 1420 1421 static void 1422 nd6_dad_ns_output(struct dadq *dp, struct ifaddr *ifa) 1423 { 1424 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1425 struct ifnet *ifp = ifa->ifa_ifp; 1426 1427 dp->dad_ns_tcount++; 1428 if ((ifp->if_flags & IFF_UP) == 0) { 1429 return; 1430 } 1431 if ((ifp->if_drv_flags & IFF_DRV_RUNNING) == 0) { 1432 return; 1433 } 1434 1435 dp->dad_ns_ocount++; 1436 nd6_ns_output(ifp, NULL, &ia->ia_addr.sin6_addr, NULL, 1); 1437 } 1438 1439 static void 1440 nd6_dad_ns_input(struct ifaddr *ifa) 1441 { 1442 INIT_VNET_INET6(curvnet); 1443 struct in6_ifaddr *ia; 1444 struct ifnet *ifp; 1445 const struct in6_addr *taddr6; 1446 struct dadq *dp; 1447 int duplicate; 1448 1449 if (ifa == NULL) 1450 panic("ifa == NULL in nd6_dad_ns_input"); 1451 1452 ia = (struct in6_ifaddr *)ifa; 1453 ifp = ifa->ifa_ifp; 1454 taddr6 = &ia->ia_addr.sin6_addr; 1455 duplicate = 0; 1456 dp = nd6_dad_find(ifa); 1457 1458 /* Quickhack - completely ignore DAD NS packets */ 1459 if (V_dad_ignore_ns) { 1460 char ip6buf[INET6_ADDRSTRLEN]; 1461 nd6log((LOG_INFO, 1462 "nd6_dad_ns_input: ignoring DAD NS packet for " 1463 "address %s(%s)\n", ip6_sprintf(ip6buf, taddr6), 1464 if_name(ifa->ifa_ifp))); 1465 return; 1466 } 1467 1468 /* 1469 * if I'm yet to start DAD, someone else started using this address 1470 * first. I have a duplicate and you win. 1471 */ 1472 if (dp == NULL || dp->dad_ns_ocount == 0) 1473 duplicate++; 1474 1475 /* XXX more checks for loopback situation - see nd6_dad_timer too */ 1476 1477 if (duplicate) { 1478 dp = NULL; /* will be freed in nd6_dad_duplicated() */ 1479 nd6_dad_duplicated(ifa); 1480 } else { 1481 /* 1482 * not sure if I got a duplicate. 1483 * increment ns count and see what happens. 1484 */ 1485 if (dp) 1486 dp->dad_ns_icount++; 1487 } 1488 } 1489 1490 static void 1491 nd6_dad_na_input(struct ifaddr *ifa) 1492 { 1493 struct dadq *dp; 1494 1495 if (ifa == NULL) 1496 panic("ifa == NULL in nd6_dad_na_input"); 1497 1498 dp = nd6_dad_find(ifa); 1499 if (dp) 1500 dp->dad_na_icount++; 1501 1502 /* remove the address. */ 1503 nd6_dad_duplicated(ifa); 1504 } 1505