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 static void nd6_na_output_fib(struct ifnet *, const struct in6_addr *, 89 const struct in6_addr *, u_long, int, struct sockaddr *, u_int); 90 91 VNET_DEFINE(int, dad_ignore_ns) = 0; /* ignore NS in DAD - specwise incorrect*/ 92 VNET_DEFINE(int, dad_maxtry) = 15; /* max # of *tries* to transmit DAD packet */ 93 #define V_dad_ignore_ns VNET(dad_ignore_ns) 94 #define V_dad_maxtry VNET(dad_maxtry) 95 96 /* 97 * Input a Neighbor Solicitation Message. 98 * 99 * Based on RFC 2461 100 * Based on RFC 2462 (duplicate address detection) 101 */ 102 void 103 nd6_ns_input(struct mbuf *m, int off, int icmp6len) 104 { 105 struct ifnet *ifp = m->m_pkthdr.rcvif; 106 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 107 struct nd_neighbor_solicit *nd_ns; 108 struct in6_addr saddr6 = ip6->ip6_src; 109 struct in6_addr daddr6 = ip6->ip6_dst; 110 struct in6_addr taddr6; 111 struct in6_addr myaddr6; 112 char *lladdr = NULL; 113 struct ifaddr *ifa = NULL; 114 int lladdrlen = 0; 115 int anycast = 0, proxy = 0, tentative = 0; 116 int tlladdr; 117 int rflag; 118 union nd_opts ndopts; 119 struct sockaddr_dl proxydl; 120 char ip6bufs[INET6_ADDRSTRLEN], ip6bufd[INET6_ADDRSTRLEN]; 121 122 rflag = (V_ip6_forwarding) ? ND_NA_FLAG_ROUTER : 0; 123 if (ND_IFINFO(ifp)->flags & ND6_IFF_ACCEPT_RTADV && V_ip6_norbit_raif) 124 rflag = 0; 125 #ifndef PULLDOWN_TEST 126 IP6_EXTHDR_CHECK(m, off, icmp6len,); 127 nd_ns = (struct nd_neighbor_solicit *)((caddr_t)ip6 + off); 128 #else 129 IP6_EXTHDR_GET(nd_ns, struct nd_neighbor_solicit *, m, off, icmp6len); 130 if (nd_ns == NULL) { 131 ICMP6STAT_INC(icp6s_tooshort); 132 return; 133 } 134 #endif 135 ip6 = mtod(m, struct ip6_hdr *); /* adjust pointer for safety */ 136 taddr6 = nd_ns->nd_ns_target; 137 if (in6_setscope(&taddr6, ifp, NULL) != 0) 138 goto bad; 139 140 if (ip6->ip6_hlim != 255) { 141 nd6log((LOG_ERR, 142 "nd6_ns_input: invalid hlim (%d) from %s to %s on %s\n", 143 ip6->ip6_hlim, ip6_sprintf(ip6bufs, &ip6->ip6_src), 144 ip6_sprintf(ip6bufd, &ip6->ip6_dst), if_name(ifp))); 145 goto bad; 146 } 147 148 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) { 149 /* dst has to be a solicited node multicast address. */ 150 if (daddr6.s6_addr16[0] == IPV6_ADDR_INT16_MLL && 151 /* don't check ifindex portion */ 152 daddr6.s6_addr32[1] == 0 && 153 daddr6.s6_addr32[2] == IPV6_ADDR_INT32_ONE && 154 daddr6.s6_addr8[12] == 0xff) { 155 ; /* good */ 156 } else { 157 nd6log((LOG_INFO, "nd6_ns_input: bad DAD packet " 158 "(wrong ip6 dst)\n")); 159 goto bad; 160 } 161 } else if (!V_nd6_onlink_ns_rfc4861) { 162 struct sockaddr_in6 src_sa6; 163 164 /* 165 * According to recent IETF discussions, it is not a good idea 166 * to accept a NS from an address which would not be deemed 167 * to be a neighbor otherwise. This point is expected to be 168 * clarified in future revisions of the specification. 169 */ 170 bzero(&src_sa6, sizeof(src_sa6)); 171 src_sa6.sin6_family = AF_INET6; 172 src_sa6.sin6_len = sizeof(src_sa6); 173 src_sa6.sin6_addr = saddr6; 174 if (nd6_is_addr_neighbor(&src_sa6, ifp) == 0) { 175 nd6log((LOG_INFO, "nd6_ns_input: " 176 "NS packet from non-neighbor\n")); 177 goto bad; 178 } 179 } 180 181 if (IN6_IS_ADDR_MULTICAST(&taddr6)) { 182 nd6log((LOG_INFO, "nd6_ns_input: bad NS target (multicast)\n")); 183 goto bad; 184 } 185 186 icmp6len -= sizeof(*nd_ns); 187 nd6_option_init(nd_ns + 1, icmp6len, &ndopts); 188 if (nd6_options(&ndopts) < 0) { 189 nd6log((LOG_INFO, 190 "nd6_ns_input: invalid ND option, ignored\n")); 191 /* nd6_options have incremented stats */ 192 goto freeit; 193 } 194 195 if (ndopts.nd_opts_src_lladdr) { 196 lladdr = (char *)(ndopts.nd_opts_src_lladdr + 1); 197 lladdrlen = ndopts.nd_opts_src_lladdr->nd_opt_len << 3; 198 } 199 200 if (IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_src) && lladdr) { 201 nd6log((LOG_INFO, "nd6_ns_input: bad DAD packet " 202 "(link-layer address option)\n")); 203 goto bad; 204 } 205 206 /* 207 * Attaching target link-layer address to the NA? 208 * (RFC 2461 7.2.4) 209 * 210 * NS IP dst is unicast/anycast MUST NOT add 211 * NS IP dst is solicited-node multicast MUST add 212 * 213 * In implementation, we add target link-layer address by default. 214 * We do not add one in MUST NOT cases. 215 */ 216 if (!IN6_IS_ADDR_MULTICAST(&daddr6)) 217 tlladdr = 0; 218 else 219 tlladdr = 1; 220 221 /* 222 * Target address (taddr6) must be either: 223 * (1) Valid unicast/anycast address for my receiving interface, 224 * (2) Unicast address for which I'm offering proxy service, or 225 * (3) "tentative" address on which DAD is being performed. 226 */ 227 /* (1) and (3) check. */ 228 if (ifp->if_carp) 229 ifa = (*carp_iamatch6_p)(ifp, &taddr6); 230 else 231 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &taddr6); 232 233 /* (2) check. */ 234 if (ifa == NULL) { 235 struct rtentry *rt; 236 struct sockaddr_in6 tsin6; 237 int need_proxy; 238 #ifdef RADIX_MPATH 239 struct route_in6 ro; 240 #endif 241 242 bzero(&tsin6, sizeof tsin6); 243 tsin6.sin6_len = sizeof(struct sockaddr_in6); 244 tsin6.sin6_family = AF_INET6; 245 tsin6.sin6_addr = taddr6; 246 247 /* Always use the default FIB. */ 248 #ifdef RADIX_MPATH 249 bzero(&ro, sizeof(ro)); 250 ro.ro_dst = tsin6; 251 rtalloc_mpath_fib((struct route *)&ro, RTF_ANNOUNCE, 252 RT_DEFAULT_FIB); 253 rt = ro.ro_rt; 254 #else 255 rt = in6_rtalloc1((struct sockaddr *)&tsin6, 0, 0, 256 RT_DEFAULT_FIB); 257 #endif 258 need_proxy = (rt && (rt->rt_flags & RTF_ANNOUNCE) != 0 && 259 rt->rt_gateway->sa_family == AF_LINK); 260 if (rt != NULL) { 261 /* 262 * Make a copy while we can be sure that rt_gateway 263 * is still stable before unlocking to avoid lock 264 * order problems. proxydl will only be used if 265 * proxy will be set in the next block. 266 */ 267 if (need_proxy) 268 proxydl = *SDL(rt->rt_gateway); 269 RTFREE_LOCKED(rt); 270 } 271 if (need_proxy) { 272 /* 273 * proxy NDP for single entry 274 */ 275 ifa = (struct ifaddr *)in6ifa_ifpforlinklocal(ifp, 276 IN6_IFF_NOTREADY|IN6_IFF_ANYCAST); 277 if (ifa) 278 proxy = 1; 279 } 280 } 281 if (ifa == NULL) { 282 /* 283 * We've got an NS packet, and we don't have that adddress 284 * assigned for us. We MUST silently ignore it. 285 * See RFC2461 7.2.3. 286 */ 287 goto freeit; 288 } 289 myaddr6 = *IFA_IN6(ifa); 290 anycast = ((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_ANYCAST; 291 tentative = ((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_TENTATIVE; 292 if (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_DUPLICATED) 293 goto freeit; 294 295 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) { 296 nd6log((LOG_INFO, "nd6_ns_input: lladdrlen mismatch for %s " 297 "(if %d, NS packet %d)\n", 298 ip6_sprintf(ip6bufs, &taddr6), 299 ifp->if_addrlen, lladdrlen - 2)); 300 goto bad; 301 } 302 303 if (IN6_ARE_ADDR_EQUAL(&myaddr6, &saddr6)) { 304 nd6log((LOG_INFO, "nd6_ns_input: duplicate IP6 address %s\n", 305 ip6_sprintf(ip6bufs, &saddr6))); 306 goto freeit; 307 } 308 309 /* 310 * We have neighbor solicitation packet, with target address equals to 311 * one of my tentative address. 312 * 313 * src addr how to process? 314 * --- --- 315 * multicast of course, invalid (rejected in ip6_input) 316 * unicast somebody is doing address resolution -> ignore 317 * unspec dup address detection 318 * 319 * The processing is defined in RFC 2462. 320 */ 321 if (tentative) { 322 /* 323 * If source address is unspecified address, it is for 324 * duplicate address detection. 325 * 326 * If not, the packet is for addess resolution; 327 * silently ignore it. 328 */ 329 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) 330 nd6_dad_ns_input(ifa); 331 332 goto freeit; 333 } 334 335 /* 336 * If the source address is unspecified address, entries must not 337 * be created or updated. 338 * It looks that sender is performing DAD. Output NA toward 339 * all-node multicast address, to tell the sender that I'm using 340 * the address. 341 * S bit ("solicited") must be zero. 342 */ 343 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) { 344 struct in6_addr in6_all; 345 346 in6_all = in6addr_linklocal_allnodes; 347 if (in6_setscope(&in6_all, ifp, NULL) != 0) 348 goto bad; 349 nd6_na_output_fib(ifp, &in6_all, &taddr6, 350 ((anycast || proxy || !tlladdr) ? 0 : ND_NA_FLAG_OVERRIDE) | 351 rflag, tlladdr, proxy ? (struct sockaddr *)&proxydl : NULL, 352 M_GETFIB(m)); 353 goto freeit; 354 } 355 356 nd6_cache_lladdr(ifp, &saddr6, lladdr, lladdrlen, 357 ND_NEIGHBOR_SOLICIT, 0); 358 359 nd6_na_output_fib(ifp, &saddr6, &taddr6, 360 ((anycast || proxy || !tlladdr) ? 0 : ND_NA_FLAG_OVERRIDE) | 361 rflag | ND_NA_FLAG_SOLICITED, tlladdr, 362 proxy ? (struct sockaddr *)&proxydl : NULL, M_GETFIB(m)); 363 freeit: 364 if (ifa != NULL) 365 ifa_free(ifa); 366 m_freem(m); 367 return; 368 369 bad: 370 nd6log((LOG_ERR, "nd6_ns_input: src=%s\n", 371 ip6_sprintf(ip6bufs, &saddr6))); 372 nd6log((LOG_ERR, "nd6_ns_input: dst=%s\n", 373 ip6_sprintf(ip6bufs, &daddr6))); 374 nd6log((LOG_ERR, "nd6_ns_input: tgt=%s\n", 375 ip6_sprintf(ip6bufs, &taddr6))); 376 ICMP6STAT_INC(icp6s_badns); 377 if (ifa != NULL) 378 ifa_free(ifa); 379 m_freem(m); 380 } 381 382 /* 383 * Output a Neighbor Solicitation Message. Caller specifies: 384 * - ICMP6 header source IP6 address 385 * - ND6 header target IP6 address 386 * - ND6 header source datalink address 387 * 388 * Based on RFC 2461 389 * Based on RFC 2462 (duplicate address detection) 390 * 391 * ln - for source address determination 392 * dad - duplicate address detection 393 */ 394 void 395 nd6_ns_output(struct ifnet *ifp, const struct in6_addr *daddr6, 396 const struct in6_addr *taddr6, struct llentry *ln, int dad) 397 { 398 struct mbuf *m; 399 struct m_tag *mtag; 400 struct ip6_hdr *ip6; 401 struct nd_neighbor_solicit *nd_ns; 402 struct ip6_moptions im6o; 403 int icmp6len; 404 int maxlen; 405 caddr_t mac; 406 struct route_in6 ro; 407 408 if (IN6_IS_ADDR_MULTICAST(taddr6)) 409 return; 410 411 /* estimate the size of message */ 412 maxlen = sizeof(*ip6) + sizeof(*nd_ns); 413 maxlen += (sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7; 414 if (max_linkhdr + maxlen >= MCLBYTES) { 415 #ifdef DIAGNOSTIC 416 printf("nd6_ns_output: max_linkhdr + maxlen >= MCLBYTES " 417 "(%d + %d > %d)\n", max_linkhdr, maxlen, MCLBYTES); 418 #endif 419 return; 420 } 421 422 if (max_linkhdr + maxlen > MHLEN) 423 m = m_getcl(M_NOWAIT, MT_DATA, M_PKTHDR); 424 else 425 m = m_gethdr(M_NOWAIT, MT_DATA); 426 if (m == NULL) 427 return; 428 429 bzero(&ro, sizeof(ro)); 430 431 if (daddr6 == NULL || IN6_IS_ADDR_MULTICAST(daddr6)) { 432 m->m_flags |= M_MCAST; 433 im6o.im6o_multicast_ifp = ifp; 434 im6o.im6o_multicast_hlim = 255; 435 im6o.im6o_multicast_loop = 0; 436 } 437 438 icmp6len = sizeof(*nd_ns); 439 m->m_pkthdr.len = m->m_len = sizeof(*ip6) + icmp6len; 440 m->m_data += max_linkhdr; /* or MH_ALIGN() equivalent? */ 441 442 /* fill neighbor solicitation packet */ 443 ip6 = mtod(m, struct ip6_hdr *); 444 ip6->ip6_flow = 0; 445 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 446 ip6->ip6_vfc |= IPV6_VERSION; 447 /* ip6->ip6_plen will be set later */ 448 ip6->ip6_nxt = IPPROTO_ICMPV6; 449 ip6->ip6_hlim = 255; 450 if (daddr6) 451 ip6->ip6_dst = *daddr6; 452 else { 453 ip6->ip6_dst.s6_addr16[0] = IPV6_ADDR_INT16_MLL; 454 ip6->ip6_dst.s6_addr16[1] = 0; 455 ip6->ip6_dst.s6_addr32[1] = 0; 456 ip6->ip6_dst.s6_addr32[2] = IPV6_ADDR_INT32_ONE; 457 ip6->ip6_dst.s6_addr32[3] = taddr6->s6_addr32[3]; 458 ip6->ip6_dst.s6_addr8[12] = 0xff; 459 if (in6_setscope(&ip6->ip6_dst, ifp, NULL) != 0) 460 goto bad; 461 } 462 if (!dad) { 463 struct ifaddr *ifa; 464 465 /* 466 * RFC2461 7.2.2: 467 * "If the source address of the packet prompting the 468 * solicitation is the same as one of the addresses assigned 469 * to the outgoing interface, that address SHOULD be placed 470 * in the IP Source Address of the outgoing solicitation. 471 * Otherwise, any one of the addresses assigned to the 472 * interface should be used." 473 * 474 * We use the source address for the prompting packet 475 * (saddr6), if: 476 * - saddr6 is given from the caller (by giving "ln"), and 477 * - saddr6 belongs to the outgoing interface. 478 * Otherwise, we perform the source address selection as usual. 479 */ 480 struct in6_addr *hsrc; 481 482 hsrc = NULL; 483 if (ln != NULL) { 484 LLE_RLOCK(ln); 485 if (ln->la_hold != NULL) { 486 struct ip6_hdr *hip6; /* hold ip6 */ 487 488 /* 489 * assuming every packet in la_hold has the same IP 490 * header 491 */ 492 hip6 = mtod(ln->la_hold, struct ip6_hdr *); 493 /* XXX pullup? */ 494 if (sizeof(*hip6) < ln->la_hold->m_len) { 495 ip6->ip6_src = hip6->ip6_src; 496 hsrc = &hip6->ip6_src; 497 } 498 } 499 LLE_RUNLOCK(ln); 500 } 501 if (hsrc && (ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, 502 hsrc)) != NULL) { 503 /* ip6_src set already. */ 504 ifa_free(ifa); 505 } else { 506 int error; 507 struct sockaddr_in6 dst_sa; 508 struct in6_addr src_in; 509 struct ifnet *oifp; 510 511 bzero(&dst_sa, sizeof(dst_sa)); 512 dst_sa.sin6_family = AF_INET6; 513 dst_sa.sin6_len = sizeof(dst_sa); 514 dst_sa.sin6_addr = ip6->ip6_dst; 515 516 oifp = ifp; 517 error = in6_selectsrc(&dst_sa, NULL, 518 NULL, &ro, NULL, &oifp, &src_in); 519 if (error) { 520 char ip6buf[INET6_ADDRSTRLEN]; 521 nd6log((LOG_DEBUG, 522 "nd6_ns_output: source can't be " 523 "determined: dst=%s, error=%d\n", 524 ip6_sprintf(ip6buf, &dst_sa.sin6_addr), 525 error)); 526 goto bad; 527 } 528 ip6->ip6_src = src_in; 529 } 530 } else { 531 /* 532 * Source address for DAD packet must always be IPv6 533 * unspecified address. (0::0) 534 * We actually don't have to 0-clear the address (we did it 535 * above), but we do so here explicitly to make the intention 536 * clearer. 537 */ 538 bzero(&ip6->ip6_src, sizeof(ip6->ip6_src)); 539 } 540 nd_ns = (struct nd_neighbor_solicit *)(ip6 + 1); 541 nd_ns->nd_ns_type = ND_NEIGHBOR_SOLICIT; 542 nd_ns->nd_ns_code = 0; 543 nd_ns->nd_ns_reserved = 0; 544 nd_ns->nd_ns_target = *taddr6; 545 in6_clearscope(&nd_ns->nd_ns_target); /* XXX */ 546 547 /* 548 * Add source link-layer address option. 549 * 550 * spec implementation 551 * --- --- 552 * DAD packet MUST NOT do not add the option 553 * there's no link layer address: 554 * impossible do not add the option 555 * there's link layer address: 556 * Multicast NS MUST add one add the option 557 * Unicast NS SHOULD add one add the option 558 */ 559 if (!dad && (mac = nd6_ifptomac(ifp))) { 560 int optlen = sizeof(struct nd_opt_hdr) + ifp->if_addrlen; 561 struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)(nd_ns + 1); 562 /* 8 byte alignments... */ 563 optlen = (optlen + 7) & ~7; 564 565 m->m_pkthdr.len += optlen; 566 m->m_len += optlen; 567 icmp6len += optlen; 568 bzero((caddr_t)nd_opt, optlen); 569 nd_opt->nd_opt_type = ND_OPT_SOURCE_LINKADDR; 570 nd_opt->nd_opt_len = optlen >> 3; 571 bcopy(mac, (caddr_t)(nd_opt + 1), ifp->if_addrlen); 572 } 573 574 ip6->ip6_plen = htons((u_short)icmp6len); 575 nd_ns->nd_ns_cksum = 0; 576 nd_ns->nd_ns_cksum = 577 in6_cksum(m, IPPROTO_ICMPV6, sizeof(*ip6), icmp6len); 578 579 if (send_sendso_input_hook != NULL) { 580 mtag = m_tag_get(PACKET_TAG_ND_OUTGOING, 581 sizeof(unsigned short), M_NOWAIT); 582 if (mtag == NULL) 583 goto bad; 584 *(unsigned short *)(mtag + 1) = nd_ns->nd_ns_type; 585 m_tag_prepend(m, mtag); 586 } 587 588 ip6_output(m, NULL, &ro, dad ? IPV6_UNSPECSRC : 0, &im6o, NULL, NULL); 589 icmp6_ifstat_inc(ifp, ifs6_out_msg); 590 icmp6_ifstat_inc(ifp, ifs6_out_neighborsolicit); 591 ICMP6STAT_INC(icp6s_outhist[ND_NEIGHBOR_SOLICIT]); 592 593 /* We don't cache this route. */ 594 RO_RTFREE(&ro); 595 596 return; 597 598 bad: 599 if (ro.ro_rt) { 600 RTFREE(ro.ro_rt); 601 } 602 m_freem(m); 603 return; 604 } 605 606 /* 607 * Neighbor advertisement input handling. 608 * 609 * Based on RFC 2461 610 * Based on RFC 2462 (duplicate address detection) 611 * 612 * the following items are not implemented yet: 613 * - proxy advertisement delay rule (RFC2461 7.2.8, last paragraph, SHOULD) 614 * - anycast advertisement delay rule (RFC2461 7.2.7, SHOULD) 615 */ 616 void 617 nd6_na_input(struct mbuf *m, int off, int icmp6len) 618 { 619 struct ifnet *ifp = m->m_pkthdr.rcvif; 620 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 621 struct nd_neighbor_advert *nd_na; 622 struct in6_addr daddr6 = ip6->ip6_dst; 623 struct in6_addr taddr6; 624 int flags; 625 int is_router; 626 int is_solicited; 627 int is_override; 628 char *lladdr = NULL; 629 int lladdrlen = 0; 630 int checklink = 0; 631 struct ifaddr *ifa; 632 struct llentry *ln = NULL; 633 union nd_opts ndopts; 634 struct mbuf *chain = NULL; 635 struct m_tag *mtag; 636 struct sockaddr_in6 sin6; 637 char ip6bufs[INET6_ADDRSTRLEN], ip6bufd[INET6_ADDRSTRLEN]; 638 639 if (ip6->ip6_hlim != 255) { 640 nd6log((LOG_ERR, 641 "nd6_na_input: invalid hlim (%d) from %s to %s on %s\n", 642 ip6->ip6_hlim, ip6_sprintf(ip6bufs, &ip6->ip6_src), 643 ip6_sprintf(ip6bufd, &ip6->ip6_dst), if_name(ifp))); 644 goto bad; 645 } 646 647 #ifndef PULLDOWN_TEST 648 IP6_EXTHDR_CHECK(m, off, icmp6len,); 649 nd_na = (struct nd_neighbor_advert *)((caddr_t)ip6 + off); 650 #else 651 IP6_EXTHDR_GET(nd_na, struct nd_neighbor_advert *, m, off, icmp6len); 652 if (nd_na == NULL) { 653 ICMP6STAT_INC(icp6s_tooshort); 654 return; 655 } 656 #endif 657 658 flags = nd_na->nd_na_flags_reserved; 659 is_router = ((flags & ND_NA_FLAG_ROUTER) != 0); 660 is_solicited = ((flags & ND_NA_FLAG_SOLICITED) != 0); 661 is_override = ((flags & ND_NA_FLAG_OVERRIDE) != 0); 662 663 taddr6 = nd_na->nd_na_target; 664 if (in6_setscope(&taddr6, ifp, NULL)) 665 goto bad; /* XXX: impossible */ 666 667 if (IN6_IS_ADDR_MULTICAST(&taddr6)) { 668 nd6log((LOG_ERR, 669 "nd6_na_input: invalid target address %s\n", 670 ip6_sprintf(ip6bufs, &taddr6))); 671 goto bad; 672 } 673 if (IN6_IS_ADDR_MULTICAST(&daddr6)) 674 if (is_solicited) { 675 nd6log((LOG_ERR, 676 "nd6_na_input: a solicited adv is multicasted\n")); 677 goto bad; 678 } 679 680 icmp6len -= sizeof(*nd_na); 681 nd6_option_init(nd_na + 1, icmp6len, &ndopts); 682 if (nd6_options(&ndopts) < 0) { 683 nd6log((LOG_INFO, 684 "nd6_na_input: invalid ND option, ignored\n")); 685 /* nd6_options have incremented stats */ 686 goto freeit; 687 } 688 689 if (ndopts.nd_opts_tgt_lladdr) { 690 lladdr = (char *)(ndopts.nd_opts_tgt_lladdr + 1); 691 lladdrlen = ndopts.nd_opts_tgt_lladdr->nd_opt_len << 3; 692 } 693 694 /* 695 * This effectively disables the DAD check on a non-master CARP 696 * address. 697 */ 698 if (ifp->if_carp) 699 ifa = (*carp_iamatch6_p)(ifp, &taddr6); 700 else 701 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &taddr6); 702 703 /* 704 * Target address matches one of my interface address. 705 * 706 * If my address is tentative, this means that there's somebody 707 * already using the same address as mine. This indicates DAD failure. 708 * This is defined in RFC 2462. 709 * 710 * Otherwise, process as defined in RFC 2461. 711 */ 712 if (ifa 713 && (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_TENTATIVE)) { 714 ifa_free(ifa); 715 nd6_dad_na_input(ifa); 716 goto freeit; 717 } 718 719 /* Just for safety, maybe unnecessary. */ 720 if (ifa) { 721 ifa_free(ifa); 722 log(LOG_ERR, 723 "nd6_na_input: duplicate IP6 address %s\n", 724 ip6_sprintf(ip6bufs, &taddr6)); 725 goto freeit; 726 } 727 728 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) { 729 nd6log((LOG_INFO, "nd6_na_input: lladdrlen mismatch for %s " 730 "(if %d, NA packet %d)\n", ip6_sprintf(ip6bufs, &taddr6), 731 ifp->if_addrlen, lladdrlen - 2)); 732 goto bad; 733 } 734 735 /* 736 * If no neighbor cache entry is found, NA SHOULD silently be 737 * discarded. 738 */ 739 IF_AFDATA_LOCK(ifp); 740 ln = nd6_lookup(&taddr6, LLE_EXCLUSIVE, ifp); 741 IF_AFDATA_UNLOCK(ifp); 742 if (ln == NULL) { 743 goto freeit; 744 } 745 746 if (ln->ln_state == ND6_LLINFO_INCOMPLETE) { 747 /* 748 * If the link-layer has address, and no lladdr option came, 749 * discard the packet. 750 */ 751 if (ifp->if_addrlen && lladdr == NULL) { 752 goto freeit; 753 } 754 755 /* 756 * Record link-layer address, and update the state. 757 */ 758 bcopy(lladdr, &ln->ll_addr, ifp->if_addrlen); 759 ln->la_flags |= LLE_VALID; 760 EVENTHANDLER_INVOKE(lle_event, ln, LLENTRY_RESOLVED); 761 if (is_solicited) { 762 ln->ln_state = ND6_LLINFO_REACHABLE; 763 ln->ln_byhint = 0; 764 if (!ND6_LLINFO_PERMANENT(ln)) { 765 nd6_llinfo_settimer_locked(ln, 766 (long)ND_IFINFO(ln->lle_tbl->llt_ifp)->reachable * hz); 767 } 768 } else { 769 ln->ln_state = ND6_LLINFO_STALE; 770 nd6_llinfo_settimer_locked(ln, (long)V_nd6_gctimer * hz); 771 } 772 if ((ln->ln_router = is_router) != 0) { 773 /* 774 * This means a router's state has changed from 775 * non-reachable to probably reachable, and might 776 * affect the status of associated prefixes.. 777 */ 778 checklink = 1; 779 } 780 } else { 781 int llchange; 782 783 /* 784 * Check if the link-layer address has changed or not. 785 */ 786 if (lladdr == NULL) 787 llchange = 0; 788 else { 789 if (ln->la_flags & LLE_VALID) { 790 if (bcmp(lladdr, &ln->ll_addr, ifp->if_addrlen)) 791 llchange = 1; 792 else 793 llchange = 0; 794 } else 795 llchange = 1; 796 } 797 798 /* 799 * This is VERY complex. Look at it with care. 800 * 801 * override solicit lladdr llchange action 802 * (L: record lladdr) 803 * 804 * 0 0 n -- (2c) 805 * 0 0 y n (2b) L 806 * 0 0 y y (1) REACHABLE->STALE 807 * 0 1 n -- (2c) *->REACHABLE 808 * 0 1 y n (2b) L *->REACHABLE 809 * 0 1 y y (1) REACHABLE->STALE 810 * 1 0 n -- (2a) 811 * 1 0 y n (2a) L 812 * 1 0 y y (2a) L *->STALE 813 * 1 1 n -- (2a) *->REACHABLE 814 * 1 1 y n (2a) L *->REACHABLE 815 * 1 1 y y (2a) L *->REACHABLE 816 */ 817 if (!is_override && (lladdr != NULL && llchange)) { /* (1) */ 818 /* 819 * If state is REACHABLE, make it STALE. 820 * no other updates should be done. 821 */ 822 if (ln->ln_state == ND6_LLINFO_REACHABLE) { 823 ln->ln_state = ND6_LLINFO_STALE; 824 nd6_llinfo_settimer_locked(ln, (long)V_nd6_gctimer * hz); 825 } 826 goto freeit; 827 } else if (is_override /* (2a) */ 828 || (!is_override && (lladdr != NULL && !llchange)) /* (2b) */ 829 || lladdr == NULL) { /* (2c) */ 830 /* 831 * Update link-local address, if any. 832 */ 833 if (lladdr != NULL) { 834 bcopy(lladdr, &ln->ll_addr, ifp->if_addrlen); 835 ln->la_flags |= LLE_VALID; 836 EVENTHANDLER_INVOKE(lle_event, ln, 837 LLENTRY_RESOLVED); 838 } 839 840 /* 841 * If solicited, make the state REACHABLE. 842 * If not solicited and the link-layer address was 843 * changed, make it STALE. 844 */ 845 if (is_solicited) { 846 ln->ln_state = ND6_LLINFO_REACHABLE; 847 ln->ln_byhint = 0; 848 if (!ND6_LLINFO_PERMANENT(ln)) { 849 nd6_llinfo_settimer_locked(ln, 850 (long)ND_IFINFO(ifp)->reachable * hz); 851 } 852 } else { 853 if (lladdr != NULL && llchange) { 854 ln->ln_state = ND6_LLINFO_STALE; 855 nd6_llinfo_settimer_locked(ln, 856 (long)V_nd6_gctimer * hz); 857 } 858 } 859 } 860 861 if (ln->ln_router && !is_router) { 862 /* 863 * The peer dropped the router flag. 864 * Remove the sender from the Default Router List and 865 * update the Destination Cache entries. 866 */ 867 struct nd_defrouter *dr; 868 struct in6_addr *in6; 869 870 in6 = &L3_ADDR_SIN6(ln)->sin6_addr; 871 872 /* 873 * Lock to protect the default router list. 874 * XXX: this might be unnecessary, since this function 875 * is only called under the network software interrupt 876 * context. However, we keep it just for safety. 877 */ 878 dr = defrouter_lookup(in6, ln->lle_tbl->llt_ifp); 879 if (dr) 880 defrtrlist_del(dr); 881 else if (ND_IFINFO(ln->lle_tbl->llt_ifp)->flags & 882 ND6_IFF_ACCEPT_RTADV) { 883 /* 884 * Even if the neighbor is not in the default 885 * router list, the neighbor may be used 886 * as a next hop for some destinations 887 * (e.g. redirect case). So we must 888 * call rt6_flush explicitly. 889 */ 890 rt6_flush(&ip6->ip6_src, ifp); 891 } 892 } 893 ln->ln_router = is_router; 894 } 895 /* XXX - QL 896 * Does this matter? 897 * rt->rt_flags &= ~RTF_REJECT; 898 */ 899 ln->la_asked = 0; 900 if (ln->la_hold) { 901 struct mbuf *m_hold, *m_hold_next; 902 903 /* 904 * reset the la_hold in advance, to explicitly 905 * prevent a la_hold lookup in nd6_output() 906 * (wouldn't happen, though...) 907 */ 908 for (m_hold = ln->la_hold, ln->la_hold = NULL; 909 m_hold; m_hold = m_hold_next) { 910 m_hold_next = m_hold->m_nextpkt; 911 m_hold->m_nextpkt = NULL; 912 /* 913 * we assume ifp is not a loopback here, so just set 914 * the 2nd argument as the 1st one. 915 */ 916 917 if (send_sendso_input_hook != NULL) { 918 mtag = m_tag_get(PACKET_TAG_ND_OUTGOING, 919 sizeof(unsigned short), M_NOWAIT); 920 if (mtag == NULL) 921 goto bad; 922 m_tag_prepend(m, mtag); 923 } 924 925 nd6_output_lle(ifp, ifp, m_hold, L3_ADDR_SIN6(ln), NULL, ln, &chain); 926 } 927 } 928 freeit: 929 if (ln != NULL) { 930 if (chain) 931 memcpy(&sin6, L3_ADDR_SIN6(ln), sizeof(sin6)); 932 LLE_WUNLOCK(ln); 933 934 if (chain) 935 nd6_output_flush(ifp, ifp, chain, &sin6, NULL); 936 } 937 if (checklink) 938 pfxlist_onlink_check(); 939 940 m_freem(m); 941 return; 942 943 bad: 944 if (ln != NULL) 945 LLE_WUNLOCK(ln); 946 947 ICMP6STAT_INC(icp6s_badna); 948 m_freem(m); 949 } 950 951 /* 952 * Neighbor advertisement output handling. 953 * 954 * Based on RFC 2461 955 * 956 * the following items are not implemented yet: 957 * - proxy advertisement delay rule (RFC2461 7.2.8, last paragraph, SHOULD) 958 * - anycast advertisement delay rule (RFC2461 7.2.7, SHOULD) 959 * 960 * tlladdr - 1 if include target link-layer address 961 * sdl0 - sockaddr_dl (= proxy NA) or NULL 962 */ 963 static void 964 nd6_na_output_fib(struct ifnet *ifp, const struct in6_addr *daddr6_0, 965 const struct in6_addr *taddr6, u_long flags, int tlladdr, 966 struct sockaddr *sdl0, u_int fibnum) 967 { 968 struct mbuf *m; 969 struct m_tag *mtag; 970 struct ifnet *oifp; 971 struct ip6_hdr *ip6; 972 struct nd_neighbor_advert *nd_na; 973 struct ip6_moptions im6o; 974 struct in6_addr src, daddr6; 975 struct sockaddr_in6 dst_sa; 976 int icmp6len, maxlen, error; 977 caddr_t mac = NULL; 978 struct route_in6 ro; 979 980 bzero(&ro, sizeof(ro)); 981 982 daddr6 = *daddr6_0; /* make a local copy for modification */ 983 984 /* estimate the size of message */ 985 maxlen = sizeof(*ip6) + sizeof(*nd_na); 986 maxlen += (sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7; 987 if (max_linkhdr + maxlen >= MCLBYTES) { 988 #ifdef DIAGNOSTIC 989 printf("nd6_na_output: max_linkhdr + maxlen >= MCLBYTES " 990 "(%d + %d > %d)\n", max_linkhdr, maxlen, MCLBYTES); 991 #endif 992 return; 993 } 994 995 if (max_linkhdr + maxlen > MHLEN) 996 m = m_getcl(M_NOWAIT, MT_DATA, M_PKTHDR); 997 else 998 m = m_gethdr(M_NOWAIT, MT_DATA); 999 if (m == NULL) 1000 return; 1001 M_SETFIB(m, fibnum); 1002 1003 if (IN6_IS_ADDR_MULTICAST(&daddr6)) { 1004 m->m_flags |= M_MCAST; 1005 im6o.im6o_multicast_ifp = ifp; 1006 im6o.im6o_multicast_hlim = 255; 1007 im6o.im6o_multicast_loop = 0; 1008 } 1009 1010 icmp6len = sizeof(*nd_na); 1011 m->m_pkthdr.len = m->m_len = sizeof(struct ip6_hdr) + icmp6len; 1012 m->m_data += max_linkhdr; /* or MH_ALIGN() equivalent? */ 1013 1014 /* fill neighbor advertisement packet */ 1015 ip6 = mtod(m, struct ip6_hdr *); 1016 ip6->ip6_flow = 0; 1017 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 1018 ip6->ip6_vfc |= IPV6_VERSION; 1019 ip6->ip6_nxt = IPPROTO_ICMPV6; 1020 ip6->ip6_hlim = 255; 1021 if (IN6_IS_ADDR_UNSPECIFIED(&daddr6)) { 1022 /* reply to DAD */ 1023 daddr6.s6_addr16[0] = IPV6_ADDR_INT16_MLL; 1024 daddr6.s6_addr16[1] = 0; 1025 daddr6.s6_addr32[1] = 0; 1026 daddr6.s6_addr32[2] = 0; 1027 daddr6.s6_addr32[3] = IPV6_ADDR_INT32_ONE; 1028 if (in6_setscope(&daddr6, ifp, NULL)) 1029 goto bad; 1030 1031 flags &= ~ND_NA_FLAG_SOLICITED; 1032 } 1033 ip6->ip6_dst = daddr6; 1034 bzero(&dst_sa, sizeof(struct sockaddr_in6)); 1035 dst_sa.sin6_family = AF_INET6; 1036 dst_sa.sin6_len = sizeof(struct sockaddr_in6); 1037 dst_sa.sin6_addr = daddr6; 1038 1039 /* 1040 * Select a source whose scope is the same as that of the dest. 1041 */ 1042 bcopy(&dst_sa, &ro.ro_dst, sizeof(dst_sa)); 1043 oifp = ifp; 1044 error = in6_selectsrc(&dst_sa, NULL, NULL, &ro, NULL, &oifp, &src); 1045 if (error) { 1046 char ip6buf[INET6_ADDRSTRLEN]; 1047 nd6log((LOG_DEBUG, "nd6_na_output: source can't be " 1048 "determined: dst=%s, error=%d\n", 1049 ip6_sprintf(ip6buf, &dst_sa.sin6_addr), error)); 1050 goto bad; 1051 } 1052 ip6->ip6_src = src; 1053 nd_na = (struct nd_neighbor_advert *)(ip6 + 1); 1054 nd_na->nd_na_type = ND_NEIGHBOR_ADVERT; 1055 nd_na->nd_na_code = 0; 1056 nd_na->nd_na_target = *taddr6; 1057 in6_clearscope(&nd_na->nd_na_target); /* XXX */ 1058 1059 /* 1060 * "tlladdr" indicates NS's condition for adding tlladdr or not. 1061 * see nd6_ns_input() for details. 1062 * Basically, if NS packet is sent to unicast/anycast addr, 1063 * target lladdr option SHOULD NOT be included. 1064 */ 1065 if (tlladdr) { 1066 /* 1067 * sdl0 != NULL indicates proxy NA. If we do proxy, use 1068 * lladdr in sdl0. If we are not proxying (sending NA for 1069 * my address) use lladdr configured for the interface. 1070 */ 1071 if (sdl0 == NULL) { 1072 if (ifp->if_carp) 1073 mac = (*carp_macmatch6_p)(ifp, m, taddr6); 1074 if (mac == NULL) 1075 mac = nd6_ifptomac(ifp); 1076 } else if (sdl0->sa_family == AF_LINK) { 1077 struct sockaddr_dl *sdl; 1078 sdl = (struct sockaddr_dl *)sdl0; 1079 if (sdl->sdl_alen == ifp->if_addrlen) 1080 mac = LLADDR(sdl); 1081 } 1082 } 1083 if (tlladdr && mac) { 1084 int optlen = sizeof(struct nd_opt_hdr) + ifp->if_addrlen; 1085 struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)(nd_na + 1); 1086 1087 /* roundup to 8 bytes alignment! */ 1088 optlen = (optlen + 7) & ~7; 1089 1090 m->m_pkthdr.len += optlen; 1091 m->m_len += optlen; 1092 icmp6len += optlen; 1093 bzero((caddr_t)nd_opt, optlen); 1094 nd_opt->nd_opt_type = ND_OPT_TARGET_LINKADDR; 1095 nd_opt->nd_opt_len = optlen >> 3; 1096 bcopy(mac, (caddr_t)(nd_opt + 1), ifp->if_addrlen); 1097 } else 1098 flags &= ~ND_NA_FLAG_OVERRIDE; 1099 1100 ip6->ip6_plen = htons((u_short)icmp6len); 1101 nd_na->nd_na_flags_reserved = flags; 1102 nd_na->nd_na_cksum = 0; 1103 nd_na->nd_na_cksum = 1104 in6_cksum(m, IPPROTO_ICMPV6, sizeof(struct ip6_hdr), icmp6len); 1105 1106 if (send_sendso_input_hook != NULL) { 1107 mtag = m_tag_get(PACKET_TAG_ND_OUTGOING, 1108 sizeof(unsigned short), M_NOWAIT); 1109 if (mtag == NULL) 1110 goto bad; 1111 *(unsigned short *)(mtag + 1) = nd_na->nd_na_type; 1112 m_tag_prepend(m, mtag); 1113 } 1114 1115 ip6_output(m, NULL, &ro, 0, &im6o, NULL, NULL); 1116 icmp6_ifstat_inc(ifp, ifs6_out_msg); 1117 icmp6_ifstat_inc(ifp, ifs6_out_neighboradvert); 1118 ICMP6STAT_INC(icp6s_outhist[ND_NEIGHBOR_ADVERT]); 1119 1120 /* We don't cache this route. */ 1121 RO_RTFREE(&ro); 1122 1123 return; 1124 1125 bad: 1126 if (ro.ro_rt) { 1127 RTFREE(ro.ro_rt); 1128 } 1129 m_freem(m); 1130 return; 1131 } 1132 1133 #ifndef BURN_BRIDGES 1134 void 1135 nd6_na_output(struct ifnet *ifp, const struct in6_addr *daddr6_0, 1136 const struct in6_addr *taddr6, u_long flags, int tlladdr, 1137 struct sockaddr *sdl0) 1138 { 1139 1140 nd6_na_output_fib(ifp, daddr6_0, taddr6, flags, tlladdr, sdl0, 1141 RT_DEFAULT_FIB); 1142 } 1143 #endif 1144 1145 caddr_t 1146 nd6_ifptomac(struct ifnet *ifp) 1147 { 1148 switch (ifp->if_type) { 1149 case IFT_ARCNET: 1150 case IFT_ETHER: 1151 case IFT_FDDI: 1152 case IFT_IEEE1394: 1153 #ifdef IFT_L2VLAN 1154 case IFT_L2VLAN: 1155 #endif 1156 #ifdef IFT_IEEE80211 1157 case IFT_IEEE80211: 1158 #endif 1159 case IFT_INFINIBAND: 1160 case IFT_BRIDGE: 1161 case IFT_ISO88025: 1162 return IF_LLADDR(ifp); 1163 default: 1164 return NULL; 1165 } 1166 } 1167 1168 struct dadq { 1169 TAILQ_ENTRY(dadq) dad_list; 1170 struct ifaddr *dad_ifa; 1171 int dad_count; /* max NS to send */ 1172 int dad_ns_tcount; /* # of trials to send NS */ 1173 int dad_ns_ocount; /* NS sent so far */ 1174 int dad_ns_icount; 1175 int dad_na_icount; 1176 struct callout dad_timer_ch; 1177 struct vnet *dad_vnet; 1178 }; 1179 1180 static VNET_DEFINE(TAILQ_HEAD(, dadq), dadq); 1181 VNET_DEFINE(int, dad_init) = 0; 1182 #define V_dadq VNET(dadq) 1183 #define V_dad_init VNET(dad_init) 1184 1185 static struct dadq * 1186 nd6_dad_find(struct ifaddr *ifa) 1187 { 1188 struct dadq *dp; 1189 1190 TAILQ_FOREACH(dp, &V_dadq, dad_list) 1191 if (dp->dad_ifa == ifa) 1192 return (dp); 1193 1194 return (NULL); 1195 } 1196 1197 static void 1198 nd6_dad_starttimer(struct dadq *dp, int ticks) 1199 { 1200 1201 callout_reset(&dp->dad_timer_ch, ticks, 1202 (void (*)(void *))nd6_dad_timer, (void *)dp); 1203 } 1204 1205 static void 1206 nd6_dad_stoptimer(struct dadq *dp) 1207 { 1208 1209 callout_stop(&dp->dad_timer_ch); 1210 } 1211 1212 /* 1213 * Start Duplicate Address Detection (DAD) for specified interface address. 1214 */ 1215 void 1216 nd6_dad_start(struct ifaddr *ifa, int delay) 1217 { 1218 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1219 struct dadq *dp; 1220 char ip6buf[INET6_ADDRSTRLEN]; 1221 1222 if (!V_dad_init) { 1223 TAILQ_INIT(&V_dadq); 1224 V_dad_init++; 1225 } 1226 1227 /* 1228 * If we don't need DAD, don't do it. 1229 * There are several cases: 1230 * - DAD is disabled (ip6_dad_count == 0) 1231 * - the interface address is anycast 1232 */ 1233 if (!(ia->ia6_flags & IN6_IFF_TENTATIVE)) { 1234 log(LOG_DEBUG, 1235 "nd6_dad_start: called with non-tentative address " 1236 "%s(%s)\n", 1237 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr), 1238 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1239 return; 1240 } 1241 if (ia->ia6_flags & IN6_IFF_ANYCAST) { 1242 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1243 return; 1244 } 1245 if (!V_ip6_dad_count) { 1246 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1247 return; 1248 } 1249 if (ifa->ifa_ifp == NULL) 1250 panic("nd6_dad_start: ifa->ifa_ifp == NULL"); 1251 if (!(ifa->ifa_ifp->if_flags & IFF_UP)) { 1252 return; 1253 } 1254 if (ND_IFINFO(ifa->ifa_ifp)->flags & ND6_IFF_IFDISABLED) 1255 return; 1256 if (nd6_dad_find(ifa) != NULL) { 1257 /* DAD already in progress */ 1258 return; 1259 } 1260 1261 dp = malloc(sizeof(*dp), M_IP6NDP, M_NOWAIT); 1262 if (dp == NULL) { 1263 log(LOG_ERR, "nd6_dad_start: memory allocation failed for " 1264 "%s(%s)\n", 1265 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr), 1266 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1267 return; 1268 } 1269 bzero(dp, sizeof(*dp)); 1270 callout_init(&dp->dad_timer_ch, 0); 1271 #ifdef VIMAGE 1272 dp->dad_vnet = curvnet; 1273 #endif 1274 TAILQ_INSERT_TAIL(&V_dadq, (struct dadq *)dp, dad_list); 1275 1276 nd6log((LOG_DEBUG, "%s: starting DAD for %s\n", if_name(ifa->ifa_ifp), 1277 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr))); 1278 1279 /* 1280 * Send NS packet for DAD, ip6_dad_count times. 1281 * Note that we must delay the first transmission, if this is the 1282 * first packet to be sent from the interface after interface 1283 * (re)initialization. 1284 */ 1285 dp->dad_ifa = ifa; 1286 ifa_ref(ifa); /* just for safety */ 1287 dp->dad_count = V_ip6_dad_count; 1288 dp->dad_ns_icount = dp->dad_na_icount = 0; 1289 dp->dad_ns_ocount = dp->dad_ns_tcount = 0; 1290 if (delay == 0) { 1291 nd6_dad_ns_output(dp, ifa); 1292 nd6_dad_starttimer(dp, 1293 (long)ND_IFINFO(ifa->ifa_ifp)->retrans * hz / 1000); 1294 } else { 1295 nd6_dad_starttimer(dp, delay); 1296 } 1297 } 1298 1299 /* 1300 * terminate DAD unconditionally. used for address removals. 1301 */ 1302 void 1303 nd6_dad_stop(struct ifaddr *ifa) 1304 { 1305 struct dadq *dp; 1306 1307 if (!V_dad_init) 1308 return; 1309 dp = nd6_dad_find(ifa); 1310 if (!dp) { 1311 /* DAD wasn't started yet */ 1312 return; 1313 } 1314 1315 nd6_dad_stoptimer(dp); 1316 1317 TAILQ_REMOVE(&V_dadq, (struct dadq *)dp, dad_list); 1318 free(dp, M_IP6NDP); 1319 dp = NULL; 1320 ifa_free(ifa); 1321 } 1322 1323 static void 1324 nd6_dad_timer(struct dadq *dp) 1325 { 1326 CURVNET_SET(dp->dad_vnet); 1327 struct ifaddr *ifa = dp->dad_ifa; 1328 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1329 char ip6buf[INET6_ADDRSTRLEN]; 1330 1331 /* Sanity check */ 1332 if (ia == NULL) { 1333 log(LOG_ERR, "nd6_dad_timer: called with null parameter\n"); 1334 goto done; 1335 } 1336 if (ia->ia6_flags & IN6_IFF_DUPLICATED) { 1337 log(LOG_ERR, "nd6_dad_timer: called with duplicated address " 1338 "%s(%s)\n", 1339 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr), 1340 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1341 goto done; 1342 } 1343 if ((ia->ia6_flags & IN6_IFF_TENTATIVE) == 0) { 1344 log(LOG_ERR, "nd6_dad_timer: called with non-tentative address " 1345 "%s(%s)\n", 1346 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr), 1347 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1348 goto done; 1349 } 1350 1351 /* timeouted with IFF_{RUNNING,UP} check */ 1352 if (dp->dad_ns_tcount > V_dad_maxtry) { 1353 nd6log((LOG_INFO, "%s: could not run DAD, driver problem?\n", 1354 if_name(ifa->ifa_ifp))); 1355 1356 TAILQ_REMOVE(&V_dadq, (struct dadq *)dp, dad_list); 1357 free(dp, M_IP6NDP); 1358 dp = NULL; 1359 ifa_free(ifa); 1360 goto done; 1361 } 1362 1363 /* Need more checks? */ 1364 if (dp->dad_ns_ocount < dp->dad_count) { 1365 /* 1366 * We have more NS to go. Send NS packet for DAD. 1367 */ 1368 nd6_dad_ns_output(dp, ifa); 1369 nd6_dad_starttimer(dp, 1370 (long)ND_IFINFO(ifa->ifa_ifp)->retrans * hz / 1000); 1371 } else { 1372 /* 1373 * We have transmitted sufficient number of DAD packets. 1374 * See what we've got. 1375 */ 1376 int duplicate; 1377 1378 duplicate = 0; 1379 1380 if (dp->dad_na_icount) { 1381 /* 1382 * the check is in nd6_dad_na_input(), 1383 * but just in case 1384 */ 1385 duplicate++; 1386 } 1387 1388 if (dp->dad_ns_icount) { 1389 /* We've seen NS, means DAD has failed. */ 1390 duplicate++; 1391 } 1392 1393 if (duplicate) { 1394 /* (*dp) will be freed in nd6_dad_duplicated() */ 1395 dp = NULL; 1396 nd6_dad_duplicated(ifa); 1397 } else { 1398 /* 1399 * We are done with DAD. No NA came, no NS came. 1400 * No duplicate address found. 1401 */ 1402 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1403 1404 nd6log((LOG_DEBUG, 1405 "%s: DAD complete for %s - no duplicates found\n", 1406 if_name(ifa->ifa_ifp), 1407 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr))); 1408 1409 TAILQ_REMOVE(&V_dadq, (struct dadq *)dp, dad_list); 1410 free(dp, M_IP6NDP); 1411 dp = NULL; 1412 ifa_free(ifa); 1413 } 1414 } 1415 1416 done: 1417 CURVNET_RESTORE(); 1418 } 1419 1420 void 1421 nd6_dad_duplicated(struct ifaddr *ifa) 1422 { 1423 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1424 struct ifnet *ifp; 1425 struct dadq *dp; 1426 char ip6buf[INET6_ADDRSTRLEN]; 1427 1428 dp = nd6_dad_find(ifa); 1429 if (dp == NULL) { 1430 log(LOG_ERR, "nd6_dad_duplicated: DAD structure not found\n"); 1431 return; 1432 } 1433 1434 log(LOG_ERR, "%s: DAD detected duplicate IPv6 address %s: " 1435 "NS in/out=%d/%d, NA in=%d\n", 1436 if_name(ifa->ifa_ifp), ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr), 1437 dp->dad_ns_icount, dp->dad_ns_ocount, dp->dad_na_icount); 1438 1439 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1440 ia->ia6_flags |= IN6_IFF_DUPLICATED; 1441 1442 /* We are done with DAD, with duplicate address found. (failure) */ 1443 nd6_dad_stoptimer(dp); 1444 1445 ifp = ifa->ifa_ifp; 1446 log(LOG_ERR, "%s: DAD complete for %s - duplicate found\n", 1447 if_name(ifp), ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr)); 1448 log(LOG_ERR, "%s: manual intervention required\n", 1449 if_name(ifp)); 1450 1451 /* 1452 * If the address is a link-local address formed from an interface 1453 * identifier based on the hardware address which is supposed to be 1454 * uniquely assigned (e.g., EUI-64 for an Ethernet interface), IP 1455 * operation on the interface SHOULD be disabled. 1456 * [RFC 4862, Section 5.4.5] 1457 */ 1458 if (IN6_IS_ADDR_LINKLOCAL(&ia->ia_addr.sin6_addr)) { 1459 struct in6_addr in6; 1460 1461 /* 1462 * To avoid over-reaction, we only apply this logic when we are 1463 * very sure that hardware addresses are supposed to be unique. 1464 */ 1465 switch (ifp->if_type) { 1466 case IFT_ETHER: 1467 case IFT_FDDI: 1468 case IFT_ATM: 1469 case IFT_IEEE1394: 1470 #ifdef IFT_IEEE80211 1471 case IFT_IEEE80211: 1472 #endif 1473 case IFT_INFINIBAND: 1474 in6 = ia->ia_addr.sin6_addr; 1475 if (in6_get_hw_ifid(ifp, &in6) == 0 && 1476 IN6_ARE_ADDR_EQUAL(&ia->ia_addr.sin6_addr, &in6)) { 1477 ND_IFINFO(ifp)->flags |= ND6_IFF_IFDISABLED; 1478 log(LOG_ERR, "%s: possible hardware address " 1479 "duplication detected, disable IPv6\n", 1480 if_name(ifp)); 1481 } 1482 break; 1483 } 1484 } 1485 1486 TAILQ_REMOVE(&V_dadq, (struct dadq *)dp, dad_list); 1487 free(dp, M_IP6NDP); 1488 dp = NULL; 1489 ifa_free(ifa); 1490 } 1491 1492 static void 1493 nd6_dad_ns_output(struct dadq *dp, struct ifaddr *ifa) 1494 { 1495 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1496 struct ifnet *ifp = ifa->ifa_ifp; 1497 1498 dp->dad_ns_tcount++; 1499 if ((ifp->if_flags & IFF_UP) == 0) { 1500 return; 1501 } 1502 if ((ifp->if_drv_flags & IFF_DRV_RUNNING) == 0) { 1503 return; 1504 } 1505 1506 dp->dad_ns_ocount++; 1507 nd6_ns_output(ifp, NULL, &ia->ia_addr.sin6_addr, NULL, 1); 1508 } 1509 1510 static void 1511 nd6_dad_ns_input(struct ifaddr *ifa) 1512 { 1513 struct in6_ifaddr *ia; 1514 struct ifnet *ifp; 1515 const struct in6_addr *taddr6; 1516 struct dadq *dp; 1517 int duplicate; 1518 1519 if (ifa == NULL) 1520 panic("ifa == NULL in nd6_dad_ns_input"); 1521 1522 ia = (struct in6_ifaddr *)ifa; 1523 ifp = ifa->ifa_ifp; 1524 taddr6 = &ia->ia_addr.sin6_addr; 1525 duplicate = 0; 1526 dp = nd6_dad_find(ifa); 1527 1528 /* Quickhack - completely ignore DAD NS packets */ 1529 if (V_dad_ignore_ns) { 1530 char ip6buf[INET6_ADDRSTRLEN]; 1531 nd6log((LOG_INFO, 1532 "nd6_dad_ns_input: ignoring DAD NS packet for " 1533 "address %s(%s)\n", ip6_sprintf(ip6buf, taddr6), 1534 if_name(ifa->ifa_ifp))); 1535 return; 1536 } 1537 1538 /* 1539 * if I'm yet to start DAD, someone else started using this address 1540 * first. I have a duplicate and you win. 1541 */ 1542 if (dp == NULL || dp->dad_ns_ocount == 0) 1543 duplicate++; 1544 1545 /* XXX more checks for loopback situation - see nd6_dad_timer too */ 1546 1547 if (duplicate) { 1548 dp = NULL; /* will be freed in nd6_dad_duplicated() */ 1549 nd6_dad_duplicated(ifa); 1550 } else { 1551 /* 1552 * not sure if I got a duplicate. 1553 * increment ns count and see what happens. 1554 */ 1555 if (dp) 1556 dp->dad_ns_icount++; 1557 } 1558 } 1559 1560 static void 1561 nd6_dad_na_input(struct ifaddr *ifa) 1562 { 1563 struct dadq *dp; 1564 1565 if (ifa == NULL) 1566 panic("ifa == NULL in nd6_dad_na_input"); 1567 1568 dp = nd6_dad_find(ifa); 1569 if (dp) 1570 dp->dad_na_icount++; 1571 1572 /* remove the address. */ 1573 nd6_dad_duplicated(ifa); 1574 } 1575