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 ip6_moptions im6o; 387 int icmp6len; 388 int maxlen; 389 caddr_t mac; 390 struct route_in6 ro; 391 392 if (IN6_IS_ADDR_MULTICAST(taddr6)) 393 return; 394 395 /* estimate the size of message */ 396 maxlen = sizeof(*ip6) + sizeof(*nd_ns); 397 maxlen += (sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7; 398 if (max_linkhdr + maxlen >= MCLBYTES) { 399 #ifdef DIAGNOSTIC 400 printf("nd6_ns_output: max_linkhdr + maxlen >= MCLBYTES " 401 "(%d + %d > %d)\n", max_linkhdr, maxlen, MCLBYTES); 402 #endif 403 return; 404 } 405 406 MGETHDR(m, M_DONTWAIT, MT_DATA); 407 if (m && max_linkhdr + maxlen >= MHLEN) { 408 MCLGET(m, M_DONTWAIT); 409 if ((m->m_flags & M_EXT) == 0) { 410 m_free(m); 411 m = NULL; 412 } 413 } 414 if (m == NULL) 415 return; 416 m->m_pkthdr.rcvif = NULL; 417 418 bzero(&ro, sizeof(ro)); 419 420 if (daddr6 == NULL || IN6_IS_ADDR_MULTICAST(daddr6)) { 421 m->m_flags |= M_MCAST; 422 im6o.im6o_multicast_ifp = ifp; 423 im6o.im6o_multicast_hlim = 255; 424 im6o.im6o_multicast_loop = 0; 425 } 426 427 icmp6len = sizeof(*nd_ns); 428 m->m_pkthdr.len = m->m_len = sizeof(*ip6) + icmp6len; 429 m->m_data += max_linkhdr; /* or MH_ALIGN() equivalent? */ 430 431 /* fill neighbor solicitation packet */ 432 ip6 = mtod(m, struct ip6_hdr *); 433 ip6->ip6_flow = 0; 434 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 435 ip6->ip6_vfc |= IPV6_VERSION; 436 /* ip6->ip6_plen will be set later */ 437 ip6->ip6_nxt = IPPROTO_ICMPV6; 438 ip6->ip6_hlim = 255; 439 if (daddr6) 440 ip6->ip6_dst = *daddr6; 441 else { 442 ip6->ip6_dst.s6_addr16[0] = IPV6_ADDR_INT16_MLL; 443 ip6->ip6_dst.s6_addr16[1] = 0; 444 ip6->ip6_dst.s6_addr32[1] = 0; 445 ip6->ip6_dst.s6_addr32[2] = IPV6_ADDR_INT32_ONE; 446 ip6->ip6_dst.s6_addr32[3] = taddr6->s6_addr32[3]; 447 ip6->ip6_dst.s6_addr8[12] = 0xff; 448 if (in6_setscope(&ip6->ip6_dst, ifp, NULL) != 0) 449 goto bad; 450 } 451 if (!dad) { 452 struct ifaddr *ifa; 453 454 /* 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 in6_addr *hsrc; 470 471 hsrc = NULL; 472 if (ln != NULL) { 473 LLE_RLOCK(ln); 474 if (ln->la_hold != NULL) { 475 struct ip6_hdr *hip6; /* hold ip6 */ 476 477 /* 478 * assuming every packet in la_hold has the same IP 479 * header 480 */ 481 hip6 = mtod(ln->la_hold, struct ip6_hdr *); 482 /* XXX pullup? */ 483 if (sizeof(*hip6) < ln->la_hold->m_len) { 484 ip6->ip6_src = hip6->ip6_src; 485 hsrc = &hip6->ip6_src; 486 } 487 } 488 LLE_RUNLOCK(ln); 489 } 490 if (hsrc && (ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, 491 hsrc)) != NULL) { 492 /* ip6_src set already. */ 493 ifa_free(ifa); 494 } else { 495 int error; 496 struct sockaddr_in6 dst_sa; 497 struct in6_addr src_in; 498 499 bzero(&dst_sa, sizeof(dst_sa)); 500 dst_sa.sin6_family = AF_INET6; 501 dst_sa.sin6_len = sizeof(dst_sa); 502 dst_sa.sin6_addr = ip6->ip6_dst; 503 504 error = in6_selectsrc(&dst_sa, NULL, 505 NULL, &ro, NULL, NULL, &src_in); 506 if (error) { 507 char ip6buf[INET6_ADDRSTRLEN]; 508 nd6log((LOG_DEBUG, 509 "nd6_ns_output: source can't be " 510 "determined: dst=%s, error=%d\n", 511 ip6_sprintf(ip6buf, &dst_sa.sin6_addr), 512 error)); 513 goto bad; 514 } 515 ip6->ip6_src = src_in; 516 } 517 } else { 518 /* 519 * Source address for DAD packet must always be IPv6 520 * unspecified address. (0::0) 521 * We actually don't have to 0-clear the address (we did it 522 * above), but we do so here explicitly to make the intention 523 * clearer. 524 */ 525 bzero(&ip6->ip6_src, sizeof(ip6->ip6_src)); 526 } 527 nd_ns = (struct nd_neighbor_solicit *)(ip6 + 1); 528 nd_ns->nd_ns_type = ND_NEIGHBOR_SOLICIT; 529 nd_ns->nd_ns_code = 0; 530 nd_ns->nd_ns_reserved = 0; 531 nd_ns->nd_ns_target = *taddr6; 532 in6_clearscope(&nd_ns->nd_ns_target); /* XXX */ 533 534 /* 535 * Add source link-layer address option. 536 * 537 * spec implementation 538 * --- --- 539 * DAD packet MUST NOT do not add the option 540 * there's no link layer address: 541 * impossible do not add the option 542 * there's link layer address: 543 * Multicast NS MUST add one add the option 544 * Unicast NS SHOULD add one add the option 545 */ 546 if (!dad && (mac = nd6_ifptomac(ifp))) { 547 int optlen = sizeof(struct nd_opt_hdr) + ifp->if_addrlen; 548 struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)(nd_ns + 1); 549 /* 8 byte alignments... */ 550 optlen = (optlen + 7) & ~7; 551 552 m->m_pkthdr.len += optlen; 553 m->m_len += optlen; 554 icmp6len += optlen; 555 bzero((caddr_t)nd_opt, optlen); 556 nd_opt->nd_opt_type = ND_OPT_SOURCE_LINKADDR; 557 nd_opt->nd_opt_len = optlen >> 3; 558 bcopy(mac, (caddr_t)(nd_opt + 1), ifp->if_addrlen); 559 } 560 561 ip6->ip6_plen = htons((u_short)icmp6len); 562 nd_ns->nd_ns_cksum = 0; 563 nd_ns->nd_ns_cksum = 564 in6_cksum(m, IPPROTO_ICMPV6, sizeof(*ip6), icmp6len); 565 566 if (send_sendso_input_hook != NULL) { 567 mtag = m_tag_get(PACKET_TAG_ND_OUTGOING, 568 sizeof(unsigned short), M_NOWAIT); 569 if (mtag == NULL) 570 goto bad; 571 *(unsigned short *)(mtag + 1) = nd_ns->nd_ns_type; 572 m_tag_prepend(m, mtag); 573 } 574 575 ip6_output(m, NULL, &ro, dad ? IPV6_UNSPECSRC : 0, &im6o, NULL, NULL); 576 icmp6_ifstat_inc(ifp, ifs6_out_msg); 577 icmp6_ifstat_inc(ifp, ifs6_out_neighborsolicit); 578 ICMP6STAT_INC(icp6s_outhist[ND_NEIGHBOR_SOLICIT]); 579 580 if (ro.ro_rt) { /* we don't cache this route. */ 581 RTFREE(ro.ro_rt); 582 } 583 return; 584 585 bad: 586 if (ro.ro_rt) { 587 RTFREE(ro.ro_rt); 588 } 589 m_freem(m); 590 return; 591 } 592 593 /* 594 * Neighbor advertisement input handling. 595 * 596 * Based on RFC 2461 597 * Based on RFC 2462 (duplicate address detection) 598 * 599 * the following items are not implemented yet: 600 * - proxy advertisement delay rule (RFC2461 7.2.8, last paragraph, SHOULD) 601 * - anycast advertisement delay rule (RFC2461 7.2.7, SHOULD) 602 */ 603 void 604 nd6_na_input(struct mbuf *m, int off, int icmp6len) 605 { 606 struct ifnet *ifp = m->m_pkthdr.rcvif; 607 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 608 struct nd_neighbor_advert *nd_na; 609 struct in6_addr daddr6 = ip6->ip6_dst; 610 struct in6_addr taddr6; 611 int flags; 612 int is_router; 613 int is_solicited; 614 int is_override; 615 char *lladdr = NULL; 616 int lladdrlen = 0; 617 int checklink = 0; 618 struct ifaddr *ifa; 619 struct llentry *ln = NULL; 620 union nd_opts ndopts; 621 struct mbuf *chain = NULL; 622 struct m_tag *mtag; 623 struct sockaddr_in6 sin6; 624 char ip6bufs[INET6_ADDRSTRLEN], ip6bufd[INET6_ADDRSTRLEN]; 625 626 if (ip6->ip6_hlim != 255) { 627 nd6log((LOG_ERR, 628 "nd6_na_input: invalid hlim (%d) from %s to %s on %s\n", 629 ip6->ip6_hlim, ip6_sprintf(ip6bufs, &ip6->ip6_src), 630 ip6_sprintf(ip6bufd, &ip6->ip6_dst), if_name(ifp))); 631 goto bad; 632 } 633 634 #ifndef PULLDOWN_TEST 635 IP6_EXTHDR_CHECK(m, off, icmp6len,); 636 nd_na = (struct nd_neighbor_advert *)((caddr_t)ip6 + off); 637 #else 638 IP6_EXTHDR_GET(nd_na, struct nd_neighbor_advert *, m, off, icmp6len); 639 if (nd_na == NULL) { 640 ICMP6STAT_INC(icp6s_tooshort); 641 return; 642 } 643 #endif 644 645 flags = nd_na->nd_na_flags_reserved; 646 is_router = ((flags & ND_NA_FLAG_ROUTER) != 0); 647 is_solicited = ((flags & ND_NA_FLAG_SOLICITED) != 0); 648 is_override = ((flags & ND_NA_FLAG_OVERRIDE) != 0); 649 650 taddr6 = nd_na->nd_na_target; 651 if (in6_setscope(&taddr6, ifp, NULL)) 652 goto bad; /* XXX: impossible */ 653 654 if (IN6_IS_ADDR_MULTICAST(&taddr6)) { 655 nd6log((LOG_ERR, 656 "nd6_na_input: invalid target address %s\n", 657 ip6_sprintf(ip6bufs, &taddr6))); 658 goto bad; 659 } 660 if (IN6_IS_ADDR_MULTICAST(&daddr6)) 661 if (is_solicited) { 662 nd6log((LOG_ERR, 663 "nd6_na_input: a solicited adv is multicasted\n")); 664 goto bad; 665 } 666 667 icmp6len -= sizeof(*nd_na); 668 nd6_option_init(nd_na + 1, icmp6len, &ndopts); 669 if (nd6_options(&ndopts) < 0) { 670 nd6log((LOG_INFO, 671 "nd6_na_input: invalid ND option, ignored\n")); 672 /* nd6_options have incremented stats */ 673 goto freeit; 674 } 675 676 if (ndopts.nd_opts_tgt_lladdr) { 677 lladdr = (char *)(ndopts.nd_opts_tgt_lladdr + 1); 678 lladdrlen = ndopts.nd_opts_tgt_lladdr->nd_opt_len << 3; 679 } 680 681 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &taddr6); 682 683 /* 684 * Target address matches one of my interface address. 685 * 686 * If my address is tentative, this means that there's somebody 687 * already using the same address as mine. This indicates DAD failure. 688 * This is defined in RFC 2462. 689 * 690 * Otherwise, process as defined in RFC 2461. 691 */ 692 if (ifa 693 && (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_TENTATIVE)) { 694 ifa_free(ifa); 695 nd6_dad_na_input(ifa); 696 goto freeit; 697 } 698 699 /* Just for safety, maybe unnecessary. */ 700 if (ifa) { 701 ifa_free(ifa); 702 log(LOG_ERR, 703 "nd6_na_input: duplicate IP6 address %s\n", 704 ip6_sprintf(ip6bufs, &taddr6)); 705 goto freeit; 706 } 707 708 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) { 709 nd6log((LOG_INFO, "nd6_na_input: lladdrlen mismatch for %s " 710 "(if %d, NA packet %d)\n", ip6_sprintf(ip6bufs, &taddr6), 711 ifp->if_addrlen, lladdrlen - 2)); 712 goto bad; 713 } 714 715 /* 716 * If no neighbor cache entry is found, NA SHOULD silently be 717 * discarded. 718 */ 719 IF_AFDATA_LOCK(ifp); 720 ln = nd6_lookup(&taddr6, LLE_EXCLUSIVE, ifp); 721 IF_AFDATA_UNLOCK(ifp); 722 if (ln == NULL) { 723 goto freeit; 724 } 725 726 if (ln->ln_state == ND6_LLINFO_INCOMPLETE) { 727 /* 728 * If the link-layer has address, and no lladdr option came, 729 * discard the packet. 730 */ 731 if (ifp->if_addrlen && lladdr == NULL) { 732 goto freeit; 733 } 734 735 /* 736 * Record link-layer address, and update the state. 737 */ 738 bcopy(lladdr, &ln->ll_addr, ifp->if_addrlen); 739 ln->la_flags |= LLE_VALID; 740 if (is_solicited) { 741 ln->ln_state = ND6_LLINFO_REACHABLE; 742 ln->ln_byhint = 0; 743 if (!ND6_LLINFO_PERMANENT(ln)) { 744 nd6_llinfo_settimer_locked(ln, 745 (long)ND_IFINFO(ln->lle_tbl->llt_ifp)->reachable * hz); 746 } 747 } else { 748 ln->ln_state = ND6_LLINFO_STALE; 749 nd6_llinfo_settimer_locked(ln, (long)V_nd6_gctimer * hz); 750 } 751 if ((ln->ln_router = is_router) != 0) { 752 /* 753 * This means a router's state has changed from 754 * non-reachable to probably reachable, and might 755 * affect the status of associated prefixes.. 756 */ 757 checklink = 1; 758 } 759 } else { 760 int llchange; 761 762 /* 763 * Check if the link-layer address has changed or not. 764 */ 765 if (lladdr == NULL) 766 llchange = 0; 767 else { 768 if (ln->la_flags & LLE_VALID) { 769 if (bcmp(lladdr, &ln->ll_addr, ifp->if_addrlen)) 770 llchange = 1; 771 else 772 llchange = 0; 773 } else 774 llchange = 1; 775 } 776 777 /* 778 * This is VERY complex. Look at it with care. 779 * 780 * override solicit lladdr llchange action 781 * (L: record lladdr) 782 * 783 * 0 0 n -- (2c) 784 * 0 0 y n (2b) L 785 * 0 0 y y (1) REACHABLE->STALE 786 * 0 1 n -- (2c) *->REACHABLE 787 * 0 1 y n (2b) L *->REACHABLE 788 * 0 1 y y (1) REACHABLE->STALE 789 * 1 0 n -- (2a) 790 * 1 0 y n (2a) L 791 * 1 0 y y (2a) L *->STALE 792 * 1 1 n -- (2a) *->REACHABLE 793 * 1 1 y n (2a) L *->REACHABLE 794 * 1 1 y y (2a) L *->REACHABLE 795 */ 796 if (!is_override && (lladdr != NULL && llchange)) { /* (1) */ 797 /* 798 * If state is REACHABLE, make it STALE. 799 * no other updates should be done. 800 */ 801 if (ln->ln_state == ND6_LLINFO_REACHABLE) { 802 ln->ln_state = ND6_LLINFO_STALE; 803 nd6_llinfo_settimer_locked(ln, (long)V_nd6_gctimer * hz); 804 } 805 goto freeit; 806 } else if (is_override /* (2a) */ 807 || (!is_override && (lladdr != NULL && !llchange)) /* (2b) */ 808 || lladdr == NULL) { /* (2c) */ 809 /* 810 * Update link-local address, if any. 811 */ 812 if (lladdr != NULL) { 813 bcopy(lladdr, &ln->ll_addr, ifp->if_addrlen); 814 ln->la_flags |= LLE_VALID; 815 } 816 817 /* 818 * If solicited, make the state REACHABLE. 819 * If not solicited and the link-layer address was 820 * changed, make it STALE. 821 */ 822 if (is_solicited) { 823 ln->ln_state = ND6_LLINFO_REACHABLE; 824 ln->ln_byhint = 0; 825 if (!ND6_LLINFO_PERMANENT(ln)) { 826 nd6_llinfo_settimer_locked(ln, 827 (long)ND_IFINFO(ifp)->reachable * hz); 828 } 829 } else { 830 if (lladdr != NULL && llchange) { 831 ln->ln_state = ND6_LLINFO_STALE; 832 nd6_llinfo_settimer_locked(ln, 833 (long)V_nd6_gctimer * hz); 834 } 835 } 836 } 837 838 if (ln->ln_router && !is_router) { 839 /* 840 * The peer dropped the router flag. 841 * Remove the sender from the Default Router List and 842 * update the Destination Cache entries. 843 */ 844 struct nd_defrouter *dr; 845 struct in6_addr *in6; 846 847 in6 = &L3_ADDR_SIN6(ln)->sin6_addr; 848 849 /* 850 * Lock to protect the default router list. 851 * XXX: this might be unnecessary, since this function 852 * is only called under the network software interrupt 853 * context. However, we keep it just for safety. 854 */ 855 dr = defrouter_lookup(in6, ln->lle_tbl->llt_ifp); 856 if (dr) 857 defrtrlist_del(dr); 858 else if (!V_ip6_forwarding) { 859 /* 860 * Even if the neighbor is not in the default 861 * router list, the neighbor may be used 862 * as a next hop for some destinations 863 * (e.g. redirect case). So we must 864 * call rt6_flush explicitly. 865 */ 866 rt6_flush(&ip6->ip6_src, ifp); 867 } 868 } 869 ln->ln_router = is_router; 870 } 871 /* XXX - QL 872 * Does this matter? 873 * rt->rt_flags &= ~RTF_REJECT; 874 */ 875 ln->la_asked = 0; 876 if (ln->la_hold) { 877 struct mbuf *m_hold, *m_hold_next; 878 879 /* 880 * reset the la_hold in advance, to explicitly 881 * prevent a la_hold lookup in nd6_output() 882 * (wouldn't happen, though...) 883 */ 884 for (m_hold = ln->la_hold, ln->la_hold = NULL; 885 m_hold; m_hold = m_hold_next) { 886 m_hold_next = m_hold->m_nextpkt; 887 m_hold->m_nextpkt = NULL; 888 /* 889 * we assume ifp is not a loopback here, so just set 890 * the 2nd argument as the 1st one. 891 */ 892 893 if (send_sendso_input_hook != NULL) { 894 mtag = m_tag_get(PACKET_TAG_ND_OUTGOING, 895 sizeof(unsigned short), M_NOWAIT); 896 if (mtag == NULL) 897 goto bad; 898 m_tag_prepend(m, mtag); 899 } 900 901 nd6_output_lle(ifp, ifp, m_hold, L3_ADDR_SIN6(ln), NULL, ln, &chain); 902 } 903 } 904 freeit: 905 if (ln != NULL) { 906 if (chain) 907 memcpy(&sin6, L3_ADDR_SIN6(ln), sizeof(sin6)); 908 LLE_WUNLOCK(ln); 909 910 if (chain) 911 nd6_output_flush(ifp, ifp, chain, &sin6, NULL); 912 } 913 if (checklink) 914 pfxlist_onlink_check(); 915 916 m_freem(m); 917 return; 918 919 bad: 920 if (ln != NULL) 921 LLE_WUNLOCK(ln); 922 923 ICMP6STAT_INC(icp6s_badna); 924 m_freem(m); 925 } 926 927 /* 928 * Neighbor advertisement output handling. 929 * 930 * Based on RFC 2461 931 * 932 * the following items are not implemented yet: 933 * - proxy advertisement delay rule (RFC2461 7.2.8, last paragraph, SHOULD) 934 * - anycast advertisement delay rule (RFC2461 7.2.7, SHOULD) 935 * 936 * tlladdr - 1 if include target link-layer address 937 * sdl0 - sockaddr_dl (= proxy NA) or NULL 938 */ 939 void 940 nd6_na_output(struct ifnet *ifp, const struct in6_addr *daddr6_0, 941 const struct in6_addr *taddr6, u_long flags, int tlladdr, 942 struct sockaddr *sdl0) 943 { 944 struct mbuf *m; 945 struct m_tag *mtag; 946 struct ip6_hdr *ip6; 947 struct nd_neighbor_advert *nd_na; 948 struct ip6_moptions im6o; 949 struct in6_addr src, daddr6; 950 struct sockaddr_in6 dst_sa; 951 int icmp6len, maxlen, error; 952 caddr_t mac = NULL; 953 struct route_in6 ro; 954 955 bzero(&ro, sizeof(ro)); 956 957 daddr6 = *daddr6_0; /* make a local copy for modification */ 958 959 /* estimate the size of message */ 960 maxlen = sizeof(*ip6) + sizeof(*nd_na); 961 maxlen += (sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7; 962 if (max_linkhdr + maxlen >= MCLBYTES) { 963 #ifdef DIAGNOSTIC 964 printf("nd6_na_output: max_linkhdr + maxlen >= MCLBYTES " 965 "(%d + %d > %d)\n", max_linkhdr, maxlen, MCLBYTES); 966 #endif 967 return; 968 } 969 970 MGETHDR(m, M_DONTWAIT, MT_DATA); 971 if (m && max_linkhdr + maxlen >= MHLEN) { 972 MCLGET(m, M_DONTWAIT); 973 if ((m->m_flags & M_EXT) == 0) { 974 m_free(m); 975 m = NULL; 976 } 977 } 978 if (m == NULL) 979 return; 980 m->m_pkthdr.rcvif = NULL; 981 982 if (IN6_IS_ADDR_MULTICAST(&daddr6)) { 983 m->m_flags |= M_MCAST; 984 im6o.im6o_multicast_ifp = ifp; 985 im6o.im6o_multicast_hlim = 255; 986 im6o.im6o_multicast_loop = 0; 987 } 988 989 icmp6len = sizeof(*nd_na); 990 m->m_pkthdr.len = m->m_len = sizeof(struct ip6_hdr) + icmp6len; 991 m->m_data += max_linkhdr; /* or MH_ALIGN() equivalent? */ 992 993 /* fill neighbor advertisement packet */ 994 ip6 = mtod(m, struct ip6_hdr *); 995 ip6->ip6_flow = 0; 996 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 997 ip6->ip6_vfc |= IPV6_VERSION; 998 ip6->ip6_nxt = IPPROTO_ICMPV6; 999 ip6->ip6_hlim = 255; 1000 if (IN6_IS_ADDR_UNSPECIFIED(&daddr6)) { 1001 /* reply to DAD */ 1002 daddr6.s6_addr16[0] = IPV6_ADDR_INT16_MLL; 1003 daddr6.s6_addr16[1] = 0; 1004 daddr6.s6_addr32[1] = 0; 1005 daddr6.s6_addr32[2] = 0; 1006 daddr6.s6_addr32[3] = IPV6_ADDR_INT32_ONE; 1007 if (in6_setscope(&daddr6, ifp, NULL)) 1008 goto bad; 1009 1010 flags &= ~ND_NA_FLAG_SOLICITED; 1011 } 1012 ip6->ip6_dst = daddr6; 1013 bzero(&dst_sa, sizeof(struct sockaddr_in6)); 1014 dst_sa.sin6_family = AF_INET6; 1015 dst_sa.sin6_len = sizeof(struct sockaddr_in6); 1016 dst_sa.sin6_addr = daddr6; 1017 1018 /* 1019 * Select a source whose scope is the same as that of the dest. 1020 */ 1021 bcopy(&dst_sa, &ro.ro_dst, sizeof(dst_sa)); 1022 error = in6_selectsrc(&dst_sa, NULL, NULL, &ro, NULL, NULL, &src); 1023 if (error) { 1024 char ip6buf[INET6_ADDRSTRLEN]; 1025 nd6log((LOG_DEBUG, "nd6_na_output: source can't be " 1026 "determined: dst=%s, error=%d\n", 1027 ip6_sprintf(ip6buf, &dst_sa.sin6_addr), error)); 1028 goto bad; 1029 } 1030 ip6->ip6_src = src; 1031 nd_na = (struct nd_neighbor_advert *)(ip6 + 1); 1032 nd_na->nd_na_type = ND_NEIGHBOR_ADVERT; 1033 nd_na->nd_na_code = 0; 1034 nd_na->nd_na_target = *taddr6; 1035 in6_clearscope(&nd_na->nd_na_target); /* XXX */ 1036 1037 /* 1038 * "tlladdr" indicates NS's condition for adding tlladdr or not. 1039 * see nd6_ns_input() for details. 1040 * Basically, if NS packet is sent to unicast/anycast addr, 1041 * target lladdr option SHOULD NOT be included. 1042 */ 1043 if (tlladdr) { 1044 /* 1045 * sdl0 != NULL indicates proxy NA. If we do proxy, use 1046 * lladdr in sdl0. If we are not proxying (sending NA for 1047 * my address) use lladdr configured for the interface. 1048 */ 1049 if (sdl0 == NULL) { 1050 if (ifp->if_carp) 1051 mac = (*carp_macmatch6_p)(ifp, m, taddr6); 1052 if (mac == NULL) 1053 mac = nd6_ifptomac(ifp); 1054 } else if (sdl0->sa_family == AF_LINK) { 1055 struct sockaddr_dl *sdl; 1056 sdl = (struct sockaddr_dl *)sdl0; 1057 if (sdl->sdl_alen == ifp->if_addrlen) 1058 mac = LLADDR(sdl); 1059 } 1060 } 1061 if (tlladdr && mac) { 1062 int optlen = sizeof(struct nd_opt_hdr) + ifp->if_addrlen; 1063 struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)(nd_na + 1); 1064 1065 /* roundup to 8 bytes alignment! */ 1066 optlen = (optlen + 7) & ~7; 1067 1068 m->m_pkthdr.len += optlen; 1069 m->m_len += optlen; 1070 icmp6len += optlen; 1071 bzero((caddr_t)nd_opt, optlen); 1072 nd_opt->nd_opt_type = ND_OPT_TARGET_LINKADDR; 1073 nd_opt->nd_opt_len = optlen >> 3; 1074 bcopy(mac, (caddr_t)(nd_opt + 1), ifp->if_addrlen); 1075 } else 1076 flags &= ~ND_NA_FLAG_OVERRIDE; 1077 1078 ip6->ip6_plen = htons((u_short)icmp6len); 1079 nd_na->nd_na_flags_reserved = flags; 1080 nd_na->nd_na_cksum = 0; 1081 nd_na->nd_na_cksum = 1082 in6_cksum(m, IPPROTO_ICMPV6, sizeof(struct ip6_hdr), icmp6len); 1083 1084 if (send_sendso_input_hook != NULL) { 1085 mtag = m_tag_get(PACKET_TAG_ND_OUTGOING, 1086 sizeof(unsigned short), M_NOWAIT); 1087 if (mtag == NULL) 1088 goto bad; 1089 *(unsigned short *)(mtag + 1) = nd_na->nd_na_type; 1090 m_tag_prepend(m, mtag); 1091 } 1092 1093 ip6_output(m, NULL, &ro, 0, &im6o, NULL, NULL); 1094 icmp6_ifstat_inc(ifp, ifs6_out_msg); 1095 icmp6_ifstat_inc(ifp, ifs6_out_neighboradvert); 1096 ICMP6STAT_INC(icp6s_outhist[ND_NEIGHBOR_ADVERT]); 1097 1098 if (ro.ro_rt) { /* we don't cache this route. */ 1099 RTFREE(ro.ro_rt); 1100 } 1101 return; 1102 1103 bad: 1104 if (ro.ro_rt) { 1105 RTFREE(ro.ro_rt); 1106 } 1107 m_freem(m); 1108 return; 1109 } 1110 1111 caddr_t 1112 nd6_ifptomac(struct ifnet *ifp) 1113 { 1114 switch (ifp->if_type) { 1115 case IFT_ARCNET: 1116 case IFT_ETHER: 1117 case IFT_FDDI: 1118 case IFT_IEEE1394: 1119 #ifdef IFT_L2VLAN 1120 case IFT_L2VLAN: 1121 #endif 1122 #ifdef IFT_IEEE80211 1123 case IFT_IEEE80211: 1124 #endif 1125 #ifdef IFT_CARP 1126 case IFT_CARP: 1127 #endif 1128 case IFT_BRIDGE: 1129 case IFT_ISO88025: 1130 return IF_LLADDR(ifp); 1131 default: 1132 return NULL; 1133 } 1134 } 1135 1136 struct dadq { 1137 TAILQ_ENTRY(dadq) dad_list; 1138 struct ifaddr *dad_ifa; 1139 int dad_count; /* max NS to send */ 1140 int dad_ns_tcount; /* # of trials to send NS */ 1141 int dad_ns_ocount; /* NS sent so far */ 1142 int dad_ns_icount; 1143 int dad_na_icount; 1144 struct callout dad_timer_ch; 1145 struct vnet *dad_vnet; 1146 }; 1147 1148 static VNET_DEFINE(TAILQ_HEAD(, dadq), dadq); 1149 VNET_DEFINE(int, dad_init) = 0; 1150 #define V_dadq VNET(dadq) 1151 #define V_dad_init VNET(dad_init) 1152 1153 static struct dadq * 1154 nd6_dad_find(struct ifaddr *ifa) 1155 { 1156 struct dadq *dp; 1157 1158 for (dp = V_dadq.tqh_first; dp; dp = dp->dad_list.tqe_next) { 1159 if (dp->dad_ifa == ifa) 1160 return dp; 1161 } 1162 return NULL; 1163 } 1164 1165 static void 1166 nd6_dad_starttimer(struct dadq *dp, int ticks) 1167 { 1168 1169 callout_reset(&dp->dad_timer_ch, ticks, 1170 (void (*)(void *))nd6_dad_timer, (void *)dp); 1171 } 1172 1173 static void 1174 nd6_dad_stoptimer(struct dadq *dp) 1175 { 1176 1177 callout_stop(&dp->dad_timer_ch); 1178 } 1179 1180 /* 1181 * Start Duplicate Address Detection (DAD) for specified interface address. 1182 */ 1183 void 1184 nd6_dad_start(struct ifaddr *ifa, int delay) 1185 { 1186 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1187 struct dadq *dp; 1188 char ip6buf[INET6_ADDRSTRLEN]; 1189 1190 if (!V_dad_init) { 1191 TAILQ_INIT(&V_dadq); 1192 V_dad_init++; 1193 } 1194 1195 /* 1196 * If we don't need DAD, don't do it. 1197 * There are several cases: 1198 * - DAD is disabled (ip6_dad_count == 0) 1199 * - the interface address is anycast 1200 */ 1201 if (!(ia->ia6_flags & IN6_IFF_TENTATIVE)) { 1202 log(LOG_DEBUG, 1203 "nd6_dad_start: called with non-tentative address " 1204 "%s(%s)\n", 1205 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr), 1206 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1207 return; 1208 } 1209 if (ia->ia6_flags & IN6_IFF_ANYCAST) { 1210 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1211 return; 1212 } 1213 if (!V_ip6_dad_count) { 1214 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1215 return; 1216 } 1217 if (ifa->ifa_ifp == NULL) 1218 panic("nd6_dad_start: ifa->ifa_ifp == NULL"); 1219 if (!(ifa->ifa_ifp->if_flags & IFF_UP)) { 1220 return; 1221 } 1222 if (ND_IFINFO(ifa->ifa_ifp)->flags & ND6_IFF_IFDISABLED) 1223 return; 1224 if (nd6_dad_find(ifa) != NULL) { 1225 /* DAD already in progress */ 1226 return; 1227 } 1228 1229 dp = malloc(sizeof(*dp), M_IP6NDP, M_NOWAIT); 1230 if (dp == NULL) { 1231 log(LOG_ERR, "nd6_dad_start: memory allocation failed for " 1232 "%s(%s)\n", 1233 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr), 1234 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1235 return; 1236 } 1237 bzero(dp, sizeof(*dp)); 1238 callout_init(&dp->dad_timer_ch, 0); 1239 #ifdef VIMAGE 1240 dp->dad_vnet = curvnet; 1241 #endif 1242 TAILQ_INSERT_TAIL(&V_dadq, (struct dadq *)dp, dad_list); 1243 1244 nd6log((LOG_DEBUG, "%s: starting DAD for %s\n", if_name(ifa->ifa_ifp), 1245 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr))); 1246 1247 /* 1248 * Send NS packet for DAD, ip6_dad_count times. 1249 * Note that we must delay the first transmission, if this is the 1250 * first packet to be sent from the interface after interface 1251 * (re)initialization. 1252 */ 1253 dp->dad_ifa = ifa; 1254 ifa_ref(ifa); /* just for safety */ 1255 dp->dad_count = V_ip6_dad_count; 1256 dp->dad_ns_icount = dp->dad_na_icount = 0; 1257 dp->dad_ns_ocount = dp->dad_ns_tcount = 0; 1258 if (delay == 0) { 1259 nd6_dad_ns_output(dp, ifa); 1260 nd6_dad_starttimer(dp, 1261 (long)ND_IFINFO(ifa->ifa_ifp)->retrans * hz / 1000); 1262 } else { 1263 nd6_dad_starttimer(dp, delay); 1264 } 1265 } 1266 1267 /* 1268 * terminate DAD unconditionally. used for address removals. 1269 */ 1270 void 1271 nd6_dad_stop(struct ifaddr *ifa) 1272 { 1273 struct dadq *dp; 1274 1275 if (!V_dad_init) 1276 return; 1277 dp = nd6_dad_find(ifa); 1278 if (!dp) { 1279 /* DAD wasn't started yet */ 1280 return; 1281 } 1282 1283 nd6_dad_stoptimer(dp); 1284 1285 TAILQ_REMOVE(&V_dadq, (struct dadq *)dp, dad_list); 1286 free(dp, M_IP6NDP); 1287 dp = NULL; 1288 ifa_free(ifa); 1289 } 1290 1291 static void 1292 nd6_dad_timer(struct dadq *dp) 1293 { 1294 CURVNET_SET(dp->dad_vnet); 1295 int s; 1296 struct ifaddr *ifa = dp->dad_ifa; 1297 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1298 char ip6buf[INET6_ADDRSTRLEN]; 1299 1300 s = splnet(); /* XXX */ 1301 1302 /* Sanity check */ 1303 if (ia == NULL) { 1304 log(LOG_ERR, "nd6_dad_timer: called with null parameter\n"); 1305 goto done; 1306 } 1307 if (ia->ia6_flags & IN6_IFF_DUPLICATED) { 1308 log(LOG_ERR, "nd6_dad_timer: called with duplicated address " 1309 "%s(%s)\n", 1310 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr), 1311 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1312 goto done; 1313 } 1314 if ((ia->ia6_flags & IN6_IFF_TENTATIVE) == 0) { 1315 log(LOG_ERR, "nd6_dad_timer: called with non-tentative address " 1316 "%s(%s)\n", 1317 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr), 1318 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1319 goto done; 1320 } 1321 1322 /* timeouted with IFF_{RUNNING,UP} check */ 1323 if (dp->dad_ns_tcount > V_dad_maxtry) { 1324 nd6log((LOG_INFO, "%s: could not run DAD, driver problem?\n", 1325 if_name(ifa->ifa_ifp))); 1326 1327 TAILQ_REMOVE(&V_dadq, (struct dadq *)dp, dad_list); 1328 free(dp, M_IP6NDP); 1329 dp = NULL; 1330 ifa_free(ifa); 1331 goto done; 1332 } 1333 1334 /* Need more checks? */ 1335 if (dp->dad_ns_ocount < dp->dad_count) { 1336 /* 1337 * We have more NS to go. Send NS packet for DAD. 1338 */ 1339 nd6_dad_ns_output(dp, ifa); 1340 nd6_dad_starttimer(dp, 1341 (long)ND_IFINFO(ifa->ifa_ifp)->retrans * hz / 1000); 1342 } else { 1343 /* 1344 * We have transmitted sufficient number of DAD packets. 1345 * See what we've got. 1346 */ 1347 int duplicate; 1348 1349 duplicate = 0; 1350 1351 if (dp->dad_na_icount) { 1352 /* 1353 * the check is in nd6_dad_na_input(), 1354 * but just in case 1355 */ 1356 duplicate++; 1357 } 1358 1359 if (dp->dad_ns_icount) { 1360 /* We've seen NS, means DAD has failed. */ 1361 duplicate++; 1362 } 1363 1364 if (duplicate) { 1365 /* (*dp) will be freed in nd6_dad_duplicated() */ 1366 dp = NULL; 1367 nd6_dad_duplicated(ifa); 1368 } else { 1369 /* 1370 * We are done with DAD. No NA came, no NS came. 1371 * No duplicate address found. 1372 */ 1373 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1374 1375 nd6log((LOG_DEBUG, 1376 "%s: DAD complete for %s - no duplicates found\n", 1377 if_name(ifa->ifa_ifp), 1378 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr))); 1379 1380 TAILQ_REMOVE(&V_dadq, (struct dadq *)dp, dad_list); 1381 free(dp, M_IP6NDP); 1382 dp = NULL; 1383 ifa_free(ifa); 1384 } 1385 } 1386 1387 done: 1388 splx(s); 1389 CURVNET_RESTORE(); 1390 } 1391 1392 void 1393 nd6_dad_duplicated(struct ifaddr *ifa) 1394 { 1395 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1396 struct ifnet *ifp; 1397 struct dadq *dp; 1398 char ip6buf[INET6_ADDRSTRLEN]; 1399 1400 dp = nd6_dad_find(ifa); 1401 if (dp == NULL) { 1402 log(LOG_ERR, "nd6_dad_duplicated: DAD structure not found\n"); 1403 return; 1404 } 1405 1406 log(LOG_ERR, "%s: DAD detected duplicate IPv6 address %s: " 1407 "NS in/out=%d/%d, NA in=%d\n", 1408 if_name(ifa->ifa_ifp), ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr), 1409 dp->dad_ns_icount, dp->dad_ns_ocount, dp->dad_na_icount); 1410 1411 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1412 ia->ia6_flags |= IN6_IFF_DUPLICATED; 1413 1414 /* We are done with DAD, with duplicate address found. (failure) */ 1415 nd6_dad_stoptimer(dp); 1416 1417 ifp = ifa->ifa_ifp; 1418 log(LOG_ERR, "%s: DAD complete for %s - duplicate found\n", 1419 if_name(ifp), ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr)); 1420 log(LOG_ERR, "%s: manual intervention required\n", 1421 if_name(ifp)); 1422 1423 /* 1424 * If the address is a link-local address formed from an interface 1425 * identifier based on the hardware address which is supposed to be 1426 * uniquely assigned (e.g., EUI-64 for an Ethernet interface), IP 1427 * operation on the interface SHOULD be disabled. 1428 * [RFC 4862, Section 5.4.5] 1429 */ 1430 if (IN6_IS_ADDR_LINKLOCAL(&ia->ia_addr.sin6_addr)) { 1431 struct in6_addr in6; 1432 1433 /* 1434 * To avoid over-reaction, we only apply this logic when we are 1435 * very sure that hardware addresses are supposed to be unique. 1436 */ 1437 switch (ifp->if_type) { 1438 case IFT_ETHER: 1439 case IFT_FDDI: 1440 case IFT_ATM: 1441 case IFT_IEEE1394: 1442 #ifdef IFT_IEEE80211 1443 case IFT_IEEE80211: 1444 #endif 1445 in6 = ia->ia_addr.sin6_addr; 1446 if (in6_get_hw_ifid(ifp, &in6) == 0 && 1447 IN6_ARE_ADDR_EQUAL(&ia->ia_addr.sin6_addr, &in6)) { 1448 ND_IFINFO(ifp)->flags |= ND6_IFF_IFDISABLED; 1449 log(LOG_ERR, "%s: possible hardware address " 1450 "duplication detected, disable IPv6\n", 1451 if_name(ifp)); 1452 } 1453 break; 1454 } 1455 } 1456 1457 TAILQ_REMOVE(&V_dadq, (struct dadq *)dp, dad_list); 1458 free(dp, M_IP6NDP); 1459 dp = NULL; 1460 ifa_free(ifa); 1461 } 1462 1463 static void 1464 nd6_dad_ns_output(struct dadq *dp, struct ifaddr *ifa) 1465 { 1466 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1467 struct ifnet *ifp = ifa->ifa_ifp; 1468 1469 dp->dad_ns_tcount++; 1470 if ((ifp->if_flags & IFF_UP) == 0) { 1471 return; 1472 } 1473 if ((ifp->if_drv_flags & IFF_DRV_RUNNING) == 0) { 1474 return; 1475 } 1476 1477 dp->dad_ns_ocount++; 1478 nd6_ns_output(ifp, NULL, &ia->ia_addr.sin6_addr, NULL, 1); 1479 } 1480 1481 static void 1482 nd6_dad_ns_input(struct ifaddr *ifa) 1483 { 1484 struct in6_ifaddr *ia; 1485 struct ifnet *ifp; 1486 const struct in6_addr *taddr6; 1487 struct dadq *dp; 1488 int duplicate; 1489 1490 if (ifa == NULL) 1491 panic("ifa == NULL in nd6_dad_ns_input"); 1492 1493 ia = (struct in6_ifaddr *)ifa; 1494 ifp = ifa->ifa_ifp; 1495 taddr6 = &ia->ia_addr.sin6_addr; 1496 duplicate = 0; 1497 dp = nd6_dad_find(ifa); 1498 1499 /* Quickhack - completely ignore DAD NS packets */ 1500 if (V_dad_ignore_ns) { 1501 char ip6buf[INET6_ADDRSTRLEN]; 1502 nd6log((LOG_INFO, 1503 "nd6_dad_ns_input: ignoring DAD NS packet for " 1504 "address %s(%s)\n", ip6_sprintf(ip6buf, taddr6), 1505 if_name(ifa->ifa_ifp))); 1506 return; 1507 } 1508 1509 /* 1510 * if I'm yet to start DAD, someone else started using this address 1511 * first. I have a duplicate and you win. 1512 */ 1513 if (dp == NULL || dp->dad_ns_ocount == 0) 1514 duplicate++; 1515 1516 /* XXX more checks for loopback situation - see nd6_dad_timer too */ 1517 1518 if (duplicate) { 1519 dp = NULL; /* will be freed in nd6_dad_duplicated() */ 1520 nd6_dad_duplicated(ifa); 1521 } else { 1522 /* 1523 * not sure if I got a duplicate. 1524 * increment ns count and see what happens. 1525 */ 1526 if (dp) 1527 dp->dad_ns_icount++; 1528 } 1529 } 1530 1531 static void 1532 nd6_dad_na_input(struct ifaddr *ifa) 1533 { 1534 struct dadq *dp; 1535 1536 if (ifa == NULL) 1537 panic("ifa == NULL in nd6_dad_na_input"); 1538 1539 dp = nd6_dad_find(ifa); 1540 if (dp) 1541 dp->dad_na_icount++; 1542 1543 /* remove the address. */ 1544 nd6_dad_duplicated(ifa); 1545 } 1546