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 MGETHDR(m, M_DONTWAIT, MT_DATA); 423 if (m && max_linkhdr + maxlen >= MHLEN) { 424 MCLGET(m, M_DONTWAIT); 425 if ((m->m_flags & M_EXT) == 0) { 426 m_free(m); 427 m = NULL; 428 } 429 } 430 if (m == NULL) 431 return; 432 m->m_pkthdr.rcvif = NULL; 433 434 bzero(&ro, sizeof(ro)); 435 436 if (daddr6 == NULL || IN6_IS_ADDR_MULTICAST(daddr6)) { 437 m->m_flags |= M_MCAST; 438 im6o.im6o_multicast_ifp = ifp; 439 im6o.im6o_multicast_hlim = 255; 440 im6o.im6o_multicast_loop = 0; 441 } 442 443 icmp6len = sizeof(*nd_ns); 444 m->m_pkthdr.len = m->m_len = sizeof(*ip6) + icmp6len; 445 m->m_data += max_linkhdr; /* or MH_ALIGN() equivalent? */ 446 447 /* fill neighbor solicitation packet */ 448 ip6 = mtod(m, struct ip6_hdr *); 449 ip6->ip6_flow = 0; 450 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 451 ip6->ip6_vfc |= IPV6_VERSION; 452 /* ip6->ip6_plen will be set later */ 453 ip6->ip6_nxt = IPPROTO_ICMPV6; 454 ip6->ip6_hlim = 255; 455 if (daddr6) 456 ip6->ip6_dst = *daddr6; 457 else { 458 ip6->ip6_dst.s6_addr16[0] = IPV6_ADDR_INT16_MLL; 459 ip6->ip6_dst.s6_addr16[1] = 0; 460 ip6->ip6_dst.s6_addr32[1] = 0; 461 ip6->ip6_dst.s6_addr32[2] = IPV6_ADDR_INT32_ONE; 462 ip6->ip6_dst.s6_addr32[3] = taddr6->s6_addr32[3]; 463 ip6->ip6_dst.s6_addr8[12] = 0xff; 464 if (in6_setscope(&ip6->ip6_dst, ifp, NULL) != 0) 465 goto bad; 466 } 467 if (!dad) { 468 struct ifaddr *ifa; 469 470 /* 471 * RFC2461 7.2.2: 472 * "If the source address of the packet prompting the 473 * solicitation is the same as one of the addresses assigned 474 * to the outgoing interface, that address SHOULD be placed 475 * in the IP Source Address of the outgoing solicitation. 476 * Otherwise, any one of the addresses assigned to the 477 * interface should be used." 478 * 479 * We use the source address for the prompting packet 480 * (saddr6), if: 481 * - saddr6 is given from the caller (by giving "ln"), and 482 * - saddr6 belongs to the outgoing interface. 483 * Otherwise, we perform the source address selection as usual. 484 */ 485 struct in6_addr *hsrc; 486 487 hsrc = NULL; 488 if (ln != NULL) { 489 LLE_RLOCK(ln); 490 if (ln->la_hold != NULL) { 491 struct ip6_hdr *hip6; /* hold ip6 */ 492 493 /* 494 * assuming every packet in la_hold has the same IP 495 * header 496 */ 497 hip6 = mtod(ln->la_hold, struct ip6_hdr *); 498 /* XXX pullup? */ 499 if (sizeof(*hip6) < ln->la_hold->m_len) { 500 ip6->ip6_src = hip6->ip6_src; 501 hsrc = &hip6->ip6_src; 502 } 503 } 504 LLE_RUNLOCK(ln); 505 } 506 if (hsrc && (ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, 507 hsrc)) != NULL) { 508 /* ip6_src set already. */ 509 ifa_free(ifa); 510 } else { 511 int error; 512 struct sockaddr_in6 dst_sa; 513 struct in6_addr src_in; 514 struct ifnet *oifp; 515 516 bzero(&dst_sa, sizeof(dst_sa)); 517 dst_sa.sin6_family = AF_INET6; 518 dst_sa.sin6_len = sizeof(dst_sa); 519 dst_sa.sin6_addr = ip6->ip6_dst; 520 521 oifp = ifp; 522 error = in6_selectsrc(&dst_sa, NULL, 523 NULL, &ro, NULL, &oifp, &src_in); 524 if (error) { 525 char ip6buf[INET6_ADDRSTRLEN]; 526 nd6log((LOG_DEBUG, 527 "nd6_ns_output: source can't be " 528 "determined: dst=%s, error=%d\n", 529 ip6_sprintf(ip6buf, &dst_sa.sin6_addr), 530 error)); 531 goto bad; 532 } 533 ip6->ip6_src = src_in; 534 } 535 } else { 536 /* 537 * Source address for DAD packet must always be IPv6 538 * unspecified address. (0::0) 539 * We actually don't have to 0-clear the address (we did it 540 * above), but we do so here explicitly to make the intention 541 * clearer. 542 */ 543 bzero(&ip6->ip6_src, sizeof(ip6->ip6_src)); 544 } 545 nd_ns = (struct nd_neighbor_solicit *)(ip6 + 1); 546 nd_ns->nd_ns_type = ND_NEIGHBOR_SOLICIT; 547 nd_ns->nd_ns_code = 0; 548 nd_ns->nd_ns_reserved = 0; 549 nd_ns->nd_ns_target = *taddr6; 550 in6_clearscope(&nd_ns->nd_ns_target); /* XXX */ 551 552 /* 553 * Add source link-layer address option. 554 * 555 * spec implementation 556 * --- --- 557 * DAD packet MUST NOT do not add the option 558 * there's no link layer address: 559 * impossible do not add the option 560 * there's link layer address: 561 * Multicast NS MUST add one add the option 562 * Unicast NS SHOULD add one add the option 563 */ 564 if (!dad && (mac = nd6_ifptomac(ifp))) { 565 int optlen = sizeof(struct nd_opt_hdr) + ifp->if_addrlen; 566 struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)(nd_ns + 1); 567 /* 8 byte alignments... */ 568 optlen = (optlen + 7) & ~7; 569 570 m->m_pkthdr.len += optlen; 571 m->m_len += optlen; 572 icmp6len += optlen; 573 bzero((caddr_t)nd_opt, optlen); 574 nd_opt->nd_opt_type = ND_OPT_SOURCE_LINKADDR; 575 nd_opt->nd_opt_len = optlen >> 3; 576 bcopy(mac, (caddr_t)(nd_opt + 1), ifp->if_addrlen); 577 } 578 579 ip6->ip6_plen = htons((u_short)icmp6len); 580 nd_ns->nd_ns_cksum = 0; 581 nd_ns->nd_ns_cksum = 582 in6_cksum(m, IPPROTO_ICMPV6, sizeof(*ip6), icmp6len); 583 584 if (send_sendso_input_hook != NULL) { 585 mtag = m_tag_get(PACKET_TAG_ND_OUTGOING, 586 sizeof(unsigned short), M_NOWAIT); 587 if (mtag == NULL) 588 goto bad; 589 *(unsigned short *)(mtag + 1) = nd_ns->nd_ns_type; 590 m_tag_prepend(m, mtag); 591 } 592 593 ip6_output(m, NULL, &ro, dad ? IPV6_UNSPECSRC : 0, &im6o, NULL, NULL); 594 icmp6_ifstat_inc(ifp, ifs6_out_msg); 595 icmp6_ifstat_inc(ifp, ifs6_out_neighborsolicit); 596 ICMP6STAT_INC(icp6s_outhist[ND_NEIGHBOR_SOLICIT]); 597 598 /* We don't cache this route. */ 599 RO_RTFREE(&ro); 600 601 return; 602 603 bad: 604 if (ro.ro_rt) { 605 RTFREE(ro.ro_rt); 606 } 607 m_freem(m); 608 return; 609 } 610 611 /* 612 * Neighbor advertisement input handling. 613 * 614 * Based on RFC 2461 615 * Based on RFC 2462 (duplicate address detection) 616 * 617 * the following items are not implemented yet: 618 * - proxy advertisement delay rule (RFC2461 7.2.8, last paragraph, SHOULD) 619 * - anycast advertisement delay rule (RFC2461 7.2.7, SHOULD) 620 */ 621 void 622 nd6_na_input(struct mbuf *m, int off, int icmp6len) 623 { 624 struct ifnet *ifp = m->m_pkthdr.rcvif; 625 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 626 struct nd_neighbor_advert *nd_na; 627 struct in6_addr daddr6 = ip6->ip6_dst; 628 struct in6_addr taddr6; 629 int flags; 630 int is_router; 631 int is_solicited; 632 int is_override; 633 char *lladdr = NULL; 634 int lladdrlen = 0; 635 int checklink = 0; 636 struct ifaddr *ifa; 637 struct llentry *ln = NULL; 638 union nd_opts ndopts; 639 struct mbuf *chain = NULL; 640 struct m_tag *mtag; 641 struct sockaddr_in6 sin6; 642 char ip6bufs[INET6_ADDRSTRLEN], ip6bufd[INET6_ADDRSTRLEN]; 643 644 if (ip6->ip6_hlim != 255) { 645 nd6log((LOG_ERR, 646 "nd6_na_input: invalid hlim (%d) from %s to %s on %s\n", 647 ip6->ip6_hlim, ip6_sprintf(ip6bufs, &ip6->ip6_src), 648 ip6_sprintf(ip6bufd, &ip6->ip6_dst), if_name(ifp))); 649 goto bad; 650 } 651 652 #ifndef PULLDOWN_TEST 653 IP6_EXTHDR_CHECK(m, off, icmp6len,); 654 nd_na = (struct nd_neighbor_advert *)((caddr_t)ip6 + off); 655 #else 656 IP6_EXTHDR_GET(nd_na, struct nd_neighbor_advert *, m, off, icmp6len); 657 if (nd_na == NULL) { 658 ICMP6STAT_INC(icp6s_tooshort); 659 return; 660 } 661 #endif 662 663 flags = nd_na->nd_na_flags_reserved; 664 is_router = ((flags & ND_NA_FLAG_ROUTER) != 0); 665 is_solicited = ((flags & ND_NA_FLAG_SOLICITED) != 0); 666 is_override = ((flags & ND_NA_FLAG_OVERRIDE) != 0); 667 668 taddr6 = nd_na->nd_na_target; 669 if (in6_setscope(&taddr6, ifp, NULL)) 670 goto bad; /* XXX: impossible */ 671 672 if (IN6_IS_ADDR_MULTICAST(&taddr6)) { 673 nd6log((LOG_ERR, 674 "nd6_na_input: invalid target address %s\n", 675 ip6_sprintf(ip6bufs, &taddr6))); 676 goto bad; 677 } 678 if (IN6_IS_ADDR_MULTICAST(&daddr6)) 679 if (is_solicited) { 680 nd6log((LOG_ERR, 681 "nd6_na_input: a solicited adv is multicasted\n")); 682 goto bad; 683 } 684 685 icmp6len -= sizeof(*nd_na); 686 nd6_option_init(nd_na + 1, icmp6len, &ndopts); 687 if (nd6_options(&ndopts) < 0) { 688 nd6log((LOG_INFO, 689 "nd6_na_input: invalid ND option, ignored\n")); 690 /* nd6_options have incremented stats */ 691 goto freeit; 692 } 693 694 if (ndopts.nd_opts_tgt_lladdr) { 695 lladdr = (char *)(ndopts.nd_opts_tgt_lladdr + 1); 696 lladdrlen = ndopts.nd_opts_tgt_lladdr->nd_opt_len << 3; 697 } 698 699 /* 700 * This effectively disables the DAD check on a non-master CARP 701 * address. 702 */ 703 if (ifp->if_carp) 704 ifa = (*carp_iamatch6_p)(ifp, &taddr6); 705 else 706 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &taddr6); 707 708 /* 709 * Target address matches one of my interface address. 710 * 711 * If my address is tentative, this means that there's somebody 712 * already using the same address as mine. This indicates DAD failure. 713 * This is defined in RFC 2462. 714 * 715 * Otherwise, process as defined in RFC 2461. 716 */ 717 if (ifa 718 && (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_TENTATIVE)) { 719 ifa_free(ifa); 720 nd6_dad_na_input(ifa); 721 goto freeit; 722 } 723 724 /* Just for safety, maybe unnecessary. */ 725 if (ifa) { 726 ifa_free(ifa); 727 log(LOG_ERR, 728 "nd6_na_input: duplicate IP6 address %s\n", 729 ip6_sprintf(ip6bufs, &taddr6)); 730 goto freeit; 731 } 732 733 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) { 734 nd6log((LOG_INFO, "nd6_na_input: lladdrlen mismatch for %s " 735 "(if %d, NA packet %d)\n", ip6_sprintf(ip6bufs, &taddr6), 736 ifp->if_addrlen, lladdrlen - 2)); 737 goto bad; 738 } 739 740 /* 741 * If no neighbor cache entry is found, NA SHOULD silently be 742 * discarded. 743 */ 744 IF_AFDATA_LOCK(ifp); 745 ln = nd6_lookup(&taddr6, LLE_EXCLUSIVE, ifp); 746 IF_AFDATA_UNLOCK(ifp); 747 if (ln == NULL) { 748 goto freeit; 749 } 750 751 if (ln->ln_state == ND6_LLINFO_INCOMPLETE) { 752 /* 753 * If the link-layer has address, and no lladdr option came, 754 * discard the packet. 755 */ 756 if (ifp->if_addrlen && lladdr == NULL) { 757 goto freeit; 758 } 759 760 /* 761 * Record link-layer address, and update the state. 762 */ 763 bcopy(lladdr, &ln->ll_addr, ifp->if_addrlen); 764 ln->la_flags |= LLE_VALID; 765 if (is_solicited) { 766 ln->ln_state = ND6_LLINFO_REACHABLE; 767 ln->ln_byhint = 0; 768 if (!ND6_LLINFO_PERMANENT(ln)) { 769 nd6_llinfo_settimer_locked(ln, 770 (long)ND_IFINFO(ln->lle_tbl->llt_ifp)->reachable * hz); 771 } 772 } else { 773 ln->ln_state = ND6_LLINFO_STALE; 774 nd6_llinfo_settimer_locked(ln, (long)V_nd6_gctimer * hz); 775 } 776 if ((ln->ln_router = is_router) != 0) { 777 /* 778 * This means a router's state has changed from 779 * non-reachable to probably reachable, and might 780 * affect the status of associated prefixes.. 781 */ 782 checklink = 1; 783 } 784 } else { 785 int llchange; 786 787 /* 788 * Check if the link-layer address has changed or not. 789 */ 790 if (lladdr == NULL) 791 llchange = 0; 792 else { 793 if (ln->la_flags & LLE_VALID) { 794 if (bcmp(lladdr, &ln->ll_addr, ifp->if_addrlen)) 795 llchange = 1; 796 else 797 llchange = 0; 798 } else 799 llchange = 1; 800 } 801 802 /* 803 * This is VERY complex. Look at it with care. 804 * 805 * override solicit lladdr llchange action 806 * (L: record lladdr) 807 * 808 * 0 0 n -- (2c) 809 * 0 0 y n (2b) L 810 * 0 0 y y (1) REACHABLE->STALE 811 * 0 1 n -- (2c) *->REACHABLE 812 * 0 1 y n (2b) L *->REACHABLE 813 * 0 1 y y (1) REACHABLE->STALE 814 * 1 0 n -- (2a) 815 * 1 0 y n (2a) L 816 * 1 0 y y (2a) L *->STALE 817 * 1 1 n -- (2a) *->REACHABLE 818 * 1 1 y n (2a) L *->REACHABLE 819 * 1 1 y y (2a) L *->REACHABLE 820 */ 821 if (!is_override && (lladdr != NULL && llchange)) { /* (1) */ 822 /* 823 * If state is REACHABLE, make it STALE. 824 * no other updates should be done. 825 */ 826 if (ln->ln_state == ND6_LLINFO_REACHABLE) { 827 ln->ln_state = ND6_LLINFO_STALE; 828 nd6_llinfo_settimer_locked(ln, (long)V_nd6_gctimer * hz); 829 } 830 goto freeit; 831 } else if (is_override /* (2a) */ 832 || (!is_override && (lladdr != NULL && !llchange)) /* (2b) */ 833 || lladdr == NULL) { /* (2c) */ 834 /* 835 * Update link-local address, if any. 836 */ 837 if (lladdr != NULL) { 838 bcopy(lladdr, &ln->ll_addr, ifp->if_addrlen); 839 ln->la_flags |= LLE_VALID; 840 } 841 842 /* 843 * If solicited, make the state REACHABLE. 844 * If not solicited and the link-layer address was 845 * changed, make it STALE. 846 */ 847 if (is_solicited) { 848 ln->ln_state = ND6_LLINFO_REACHABLE; 849 ln->ln_byhint = 0; 850 if (!ND6_LLINFO_PERMANENT(ln)) { 851 nd6_llinfo_settimer_locked(ln, 852 (long)ND_IFINFO(ifp)->reachable * hz); 853 } 854 } else { 855 if (lladdr != NULL && llchange) { 856 ln->ln_state = ND6_LLINFO_STALE; 857 nd6_llinfo_settimer_locked(ln, 858 (long)V_nd6_gctimer * hz); 859 } 860 } 861 } 862 863 if (ln->ln_router && !is_router) { 864 /* 865 * The peer dropped the router flag. 866 * Remove the sender from the Default Router List and 867 * update the Destination Cache entries. 868 */ 869 struct nd_defrouter *dr; 870 struct in6_addr *in6; 871 872 in6 = &L3_ADDR_SIN6(ln)->sin6_addr; 873 874 /* 875 * Lock to protect the default router list. 876 * XXX: this might be unnecessary, since this function 877 * is only called under the network software interrupt 878 * context. However, we keep it just for safety. 879 */ 880 dr = defrouter_lookup(in6, ln->lle_tbl->llt_ifp); 881 if (dr) 882 defrtrlist_del(dr); 883 else if (ND_IFINFO(ln->lle_tbl->llt_ifp)->flags & 884 ND6_IFF_ACCEPT_RTADV) { 885 /* 886 * Even if the neighbor is not in the default 887 * router list, the neighbor may be used 888 * as a next hop for some destinations 889 * (e.g. redirect case). So we must 890 * call rt6_flush explicitly. 891 */ 892 rt6_flush(&ip6->ip6_src, ifp); 893 } 894 } 895 ln->ln_router = is_router; 896 } 897 /* XXX - QL 898 * Does this matter? 899 * rt->rt_flags &= ~RTF_REJECT; 900 */ 901 ln->la_asked = 0; 902 if (ln->la_hold) { 903 struct mbuf *m_hold, *m_hold_next; 904 905 /* 906 * reset the la_hold in advance, to explicitly 907 * prevent a la_hold lookup in nd6_output() 908 * (wouldn't happen, though...) 909 */ 910 for (m_hold = ln->la_hold, ln->la_hold = NULL; 911 m_hold; m_hold = m_hold_next) { 912 m_hold_next = m_hold->m_nextpkt; 913 m_hold->m_nextpkt = NULL; 914 /* 915 * we assume ifp is not a loopback here, so just set 916 * the 2nd argument as the 1st one. 917 */ 918 919 if (send_sendso_input_hook != NULL) { 920 mtag = m_tag_get(PACKET_TAG_ND_OUTGOING, 921 sizeof(unsigned short), M_NOWAIT); 922 if (mtag == NULL) 923 goto bad; 924 m_tag_prepend(m, mtag); 925 } 926 927 nd6_output_lle(ifp, ifp, m_hold, L3_ADDR_SIN6(ln), NULL, ln, &chain); 928 } 929 } 930 freeit: 931 if (ln != NULL) { 932 if (chain) 933 memcpy(&sin6, L3_ADDR_SIN6(ln), sizeof(sin6)); 934 LLE_WUNLOCK(ln); 935 936 if (chain) 937 nd6_output_flush(ifp, ifp, chain, &sin6, NULL); 938 } 939 if (checklink) 940 pfxlist_onlink_check(); 941 942 m_freem(m); 943 return; 944 945 bad: 946 if (ln != NULL) 947 LLE_WUNLOCK(ln); 948 949 ICMP6STAT_INC(icp6s_badna); 950 m_freem(m); 951 } 952 953 /* 954 * Neighbor advertisement output handling. 955 * 956 * Based on RFC 2461 957 * 958 * the following items are not implemented yet: 959 * - proxy advertisement delay rule (RFC2461 7.2.8, last paragraph, SHOULD) 960 * - anycast advertisement delay rule (RFC2461 7.2.7, SHOULD) 961 * 962 * tlladdr - 1 if include target link-layer address 963 * sdl0 - sockaddr_dl (= proxy NA) or NULL 964 */ 965 static void 966 nd6_na_output_fib(struct ifnet *ifp, const struct in6_addr *daddr6_0, 967 const struct in6_addr *taddr6, u_long flags, int tlladdr, 968 struct sockaddr *sdl0, u_int fibnum) 969 { 970 struct mbuf *m; 971 struct m_tag *mtag; 972 struct ifnet *oifp; 973 struct ip6_hdr *ip6; 974 struct nd_neighbor_advert *nd_na; 975 struct ip6_moptions im6o; 976 struct in6_addr src, daddr6; 977 struct sockaddr_in6 dst_sa; 978 int icmp6len, maxlen, error; 979 caddr_t mac = NULL; 980 struct route_in6 ro; 981 982 bzero(&ro, sizeof(ro)); 983 984 daddr6 = *daddr6_0; /* make a local copy for modification */ 985 986 /* estimate the size of message */ 987 maxlen = sizeof(*ip6) + sizeof(*nd_na); 988 maxlen += (sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7; 989 if (max_linkhdr + maxlen >= MCLBYTES) { 990 #ifdef DIAGNOSTIC 991 printf("nd6_na_output: max_linkhdr + maxlen >= MCLBYTES " 992 "(%d + %d > %d)\n", max_linkhdr, maxlen, MCLBYTES); 993 #endif 994 return; 995 } 996 997 MGETHDR(m, M_DONTWAIT, MT_DATA); 998 if (m && max_linkhdr + maxlen >= MHLEN) { 999 MCLGET(m, M_DONTWAIT); 1000 if ((m->m_flags & M_EXT) == 0) { 1001 m_free(m); 1002 m = NULL; 1003 } 1004 } 1005 if (m == NULL) 1006 return; 1007 m->m_pkthdr.rcvif = NULL; 1008 M_SETFIB(m, fibnum); 1009 1010 if (IN6_IS_ADDR_MULTICAST(&daddr6)) { 1011 m->m_flags |= M_MCAST; 1012 im6o.im6o_multicast_ifp = ifp; 1013 im6o.im6o_multicast_hlim = 255; 1014 im6o.im6o_multicast_loop = 0; 1015 } 1016 1017 icmp6len = sizeof(*nd_na); 1018 m->m_pkthdr.len = m->m_len = sizeof(struct ip6_hdr) + icmp6len; 1019 m->m_data += max_linkhdr; /* or MH_ALIGN() equivalent? */ 1020 1021 /* fill neighbor advertisement packet */ 1022 ip6 = mtod(m, struct ip6_hdr *); 1023 ip6->ip6_flow = 0; 1024 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 1025 ip6->ip6_vfc |= IPV6_VERSION; 1026 ip6->ip6_nxt = IPPROTO_ICMPV6; 1027 ip6->ip6_hlim = 255; 1028 if (IN6_IS_ADDR_UNSPECIFIED(&daddr6)) { 1029 /* reply to DAD */ 1030 daddr6.s6_addr16[0] = IPV6_ADDR_INT16_MLL; 1031 daddr6.s6_addr16[1] = 0; 1032 daddr6.s6_addr32[1] = 0; 1033 daddr6.s6_addr32[2] = 0; 1034 daddr6.s6_addr32[3] = IPV6_ADDR_INT32_ONE; 1035 if (in6_setscope(&daddr6, ifp, NULL)) 1036 goto bad; 1037 1038 flags &= ~ND_NA_FLAG_SOLICITED; 1039 } 1040 ip6->ip6_dst = daddr6; 1041 bzero(&dst_sa, sizeof(struct sockaddr_in6)); 1042 dst_sa.sin6_family = AF_INET6; 1043 dst_sa.sin6_len = sizeof(struct sockaddr_in6); 1044 dst_sa.sin6_addr = daddr6; 1045 1046 /* 1047 * Select a source whose scope is the same as that of the dest. 1048 */ 1049 bcopy(&dst_sa, &ro.ro_dst, sizeof(dst_sa)); 1050 oifp = ifp; 1051 error = in6_selectsrc(&dst_sa, NULL, NULL, &ro, NULL, &oifp, &src); 1052 if (error) { 1053 char ip6buf[INET6_ADDRSTRLEN]; 1054 nd6log((LOG_DEBUG, "nd6_na_output: source can't be " 1055 "determined: dst=%s, error=%d\n", 1056 ip6_sprintf(ip6buf, &dst_sa.sin6_addr), error)); 1057 goto bad; 1058 } 1059 ip6->ip6_src = src; 1060 nd_na = (struct nd_neighbor_advert *)(ip6 + 1); 1061 nd_na->nd_na_type = ND_NEIGHBOR_ADVERT; 1062 nd_na->nd_na_code = 0; 1063 nd_na->nd_na_target = *taddr6; 1064 in6_clearscope(&nd_na->nd_na_target); /* XXX */ 1065 1066 /* 1067 * "tlladdr" indicates NS's condition for adding tlladdr or not. 1068 * see nd6_ns_input() for details. 1069 * Basically, if NS packet is sent to unicast/anycast addr, 1070 * target lladdr option SHOULD NOT be included. 1071 */ 1072 if (tlladdr) { 1073 /* 1074 * sdl0 != NULL indicates proxy NA. If we do proxy, use 1075 * lladdr in sdl0. If we are not proxying (sending NA for 1076 * my address) use lladdr configured for the interface. 1077 */ 1078 if (sdl0 == NULL) { 1079 if (ifp->if_carp) 1080 mac = (*carp_macmatch6_p)(ifp, m, taddr6); 1081 if (mac == NULL) 1082 mac = nd6_ifptomac(ifp); 1083 } else if (sdl0->sa_family == AF_LINK) { 1084 struct sockaddr_dl *sdl; 1085 sdl = (struct sockaddr_dl *)sdl0; 1086 if (sdl->sdl_alen == ifp->if_addrlen) 1087 mac = LLADDR(sdl); 1088 } 1089 } 1090 if (tlladdr && mac) { 1091 int optlen = sizeof(struct nd_opt_hdr) + ifp->if_addrlen; 1092 struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)(nd_na + 1); 1093 1094 /* roundup to 8 bytes alignment! */ 1095 optlen = (optlen + 7) & ~7; 1096 1097 m->m_pkthdr.len += optlen; 1098 m->m_len += optlen; 1099 icmp6len += optlen; 1100 bzero((caddr_t)nd_opt, optlen); 1101 nd_opt->nd_opt_type = ND_OPT_TARGET_LINKADDR; 1102 nd_opt->nd_opt_len = optlen >> 3; 1103 bcopy(mac, (caddr_t)(nd_opt + 1), ifp->if_addrlen); 1104 } else 1105 flags &= ~ND_NA_FLAG_OVERRIDE; 1106 1107 ip6->ip6_plen = htons((u_short)icmp6len); 1108 nd_na->nd_na_flags_reserved = flags; 1109 nd_na->nd_na_cksum = 0; 1110 nd_na->nd_na_cksum = 1111 in6_cksum(m, IPPROTO_ICMPV6, sizeof(struct ip6_hdr), icmp6len); 1112 1113 if (send_sendso_input_hook != NULL) { 1114 mtag = m_tag_get(PACKET_TAG_ND_OUTGOING, 1115 sizeof(unsigned short), M_NOWAIT); 1116 if (mtag == NULL) 1117 goto bad; 1118 *(unsigned short *)(mtag + 1) = nd_na->nd_na_type; 1119 m_tag_prepend(m, mtag); 1120 } 1121 1122 ip6_output(m, NULL, &ro, 0, &im6o, NULL, NULL); 1123 icmp6_ifstat_inc(ifp, ifs6_out_msg); 1124 icmp6_ifstat_inc(ifp, ifs6_out_neighboradvert); 1125 ICMP6STAT_INC(icp6s_outhist[ND_NEIGHBOR_ADVERT]); 1126 1127 /* We don't cache this route. */ 1128 RO_RTFREE(&ro); 1129 1130 return; 1131 1132 bad: 1133 if (ro.ro_rt) { 1134 RTFREE(ro.ro_rt); 1135 } 1136 m_freem(m); 1137 return; 1138 } 1139 1140 #ifndef BURN_BRIDGES 1141 void 1142 nd6_na_output(struct ifnet *ifp, const struct in6_addr *daddr6_0, 1143 const struct in6_addr *taddr6, u_long flags, int tlladdr, 1144 struct sockaddr *sdl0) 1145 { 1146 1147 nd6_na_output_fib(ifp, daddr6_0, taddr6, flags, tlladdr, sdl0, 1148 RT_DEFAULT_FIB); 1149 } 1150 #endif 1151 1152 caddr_t 1153 nd6_ifptomac(struct ifnet *ifp) 1154 { 1155 switch (ifp->if_type) { 1156 case IFT_ARCNET: 1157 case IFT_ETHER: 1158 case IFT_FDDI: 1159 case IFT_IEEE1394: 1160 #ifdef IFT_L2VLAN 1161 case IFT_L2VLAN: 1162 #endif 1163 #ifdef IFT_IEEE80211 1164 case IFT_IEEE80211: 1165 #endif 1166 case IFT_INFINIBAND: 1167 case IFT_BRIDGE: 1168 case IFT_ISO88025: 1169 return IF_LLADDR(ifp); 1170 default: 1171 return NULL; 1172 } 1173 } 1174 1175 struct dadq { 1176 TAILQ_ENTRY(dadq) dad_list; 1177 struct ifaddr *dad_ifa; 1178 int dad_count; /* max NS to send */ 1179 int dad_ns_tcount; /* # of trials to send NS */ 1180 int dad_ns_ocount; /* NS sent so far */ 1181 int dad_ns_icount; 1182 int dad_na_icount; 1183 struct callout dad_timer_ch; 1184 struct vnet *dad_vnet; 1185 }; 1186 1187 static VNET_DEFINE(TAILQ_HEAD(, dadq), dadq); 1188 VNET_DEFINE(int, dad_init) = 0; 1189 #define V_dadq VNET(dadq) 1190 #define V_dad_init VNET(dad_init) 1191 1192 static struct dadq * 1193 nd6_dad_find(struct ifaddr *ifa) 1194 { 1195 struct dadq *dp; 1196 1197 TAILQ_FOREACH(dp, &V_dadq, dad_list) 1198 if (dp->dad_ifa == ifa) 1199 return (dp); 1200 1201 return (NULL); 1202 } 1203 1204 static void 1205 nd6_dad_starttimer(struct dadq *dp, int ticks) 1206 { 1207 1208 callout_reset(&dp->dad_timer_ch, ticks, 1209 (void (*)(void *))nd6_dad_timer, (void *)dp); 1210 } 1211 1212 static void 1213 nd6_dad_stoptimer(struct dadq *dp) 1214 { 1215 1216 callout_stop(&dp->dad_timer_ch); 1217 } 1218 1219 /* 1220 * Start Duplicate Address Detection (DAD) for specified interface address. 1221 */ 1222 void 1223 nd6_dad_start(struct ifaddr *ifa, int delay) 1224 { 1225 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1226 struct dadq *dp; 1227 char ip6buf[INET6_ADDRSTRLEN]; 1228 1229 if (!V_dad_init) { 1230 TAILQ_INIT(&V_dadq); 1231 V_dad_init++; 1232 } 1233 1234 /* 1235 * If we don't need DAD, don't do it. 1236 * There are several cases: 1237 * - DAD is disabled (ip6_dad_count == 0) 1238 * - the interface address is anycast 1239 */ 1240 if (!(ia->ia6_flags & IN6_IFF_TENTATIVE)) { 1241 log(LOG_DEBUG, 1242 "nd6_dad_start: called with non-tentative address " 1243 "%s(%s)\n", 1244 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr), 1245 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1246 return; 1247 } 1248 if (ia->ia6_flags & IN6_IFF_ANYCAST) { 1249 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1250 return; 1251 } 1252 if (!V_ip6_dad_count) { 1253 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1254 return; 1255 } 1256 if (ifa->ifa_ifp == NULL) 1257 panic("nd6_dad_start: ifa->ifa_ifp == NULL"); 1258 if (!(ifa->ifa_ifp->if_flags & IFF_UP)) { 1259 return; 1260 } 1261 if (ND_IFINFO(ifa->ifa_ifp)->flags & ND6_IFF_IFDISABLED) 1262 return; 1263 if (nd6_dad_find(ifa) != NULL) { 1264 /* DAD already in progress */ 1265 return; 1266 } 1267 1268 dp = malloc(sizeof(*dp), M_IP6NDP, M_NOWAIT); 1269 if (dp == NULL) { 1270 log(LOG_ERR, "nd6_dad_start: memory allocation failed for " 1271 "%s(%s)\n", 1272 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr), 1273 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1274 return; 1275 } 1276 bzero(dp, sizeof(*dp)); 1277 callout_init(&dp->dad_timer_ch, 0); 1278 #ifdef VIMAGE 1279 dp->dad_vnet = curvnet; 1280 #endif 1281 TAILQ_INSERT_TAIL(&V_dadq, (struct dadq *)dp, dad_list); 1282 1283 nd6log((LOG_DEBUG, "%s: starting DAD for %s\n", if_name(ifa->ifa_ifp), 1284 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr))); 1285 1286 /* 1287 * Send NS packet for DAD, ip6_dad_count times. 1288 * Note that we must delay the first transmission, if this is the 1289 * first packet to be sent from the interface after interface 1290 * (re)initialization. 1291 */ 1292 dp->dad_ifa = ifa; 1293 ifa_ref(ifa); /* just for safety */ 1294 dp->dad_count = V_ip6_dad_count; 1295 dp->dad_ns_icount = dp->dad_na_icount = 0; 1296 dp->dad_ns_ocount = dp->dad_ns_tcount = 0; 1297 if (delay == 0) { 1298 nd6_dad_ns_output(dp, ifa); 1299 nd6_dad_starttimer(dp, 1300 (long)ND_IFINFO(ifa->ifa_ifp)->retrans * hz / 1000); 1301 } else { 1302 nd6_dad_starttimer(dp, delay); 1303 } 1304 } 1305 1306 /* 1307 * terminate DAD unconditionally. used for address removals. 1308 */ 1309 void 1310 nd6_dad_stop(struct ifaddr *ifa) 1311 { 1312 struct dadq *dp; 1313 1314 if (!V_dad_init) 1315 return; 1316 dp = nd6_dad_find(ifa); 1317 if (!dp) { 1318 /* DAD wasn't started yet */ 1319 return; 1320 } 1321 1322 nd6_dad_stoptimer(dp); 1323 1324 TAILQ_REMOVE(&V_dadq, (struct dadq *)dp, dad_list); 1325 free(dp, M_IP6NDP); 1326 dp = NULL; 1327 ifa_free(ifa); 1328 } 1329 1330 static void 1331 nd6_dad_timer(struct dadq *dp) 1332 { 1333 CURVNET_SET(dp->dad_vnet); 1334 struct ifaddr *ifa = dp->dad_ifa; 1335 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1336 char ip6buf[INET6_ADDRSTRLEN]; 1337 1338 /* Sanity check */ 1339 if (ia == NULL) { 1340 log(LOG_ERR, "nd6_dad_timer: called with null parameter\n"); 1341 goto done; 1342 } 1343 if (ia->ia6_flags & IN6_IFF_DUPLICATED) { 1344 log(LOG_ERR, "nd6_dad_timer: called with duplicated 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 if ((ia->ia6_flags & IN6_IFF_TENTATIVE) == 0) { 1351 log(LOG_ERR, "nd6_dad_timer: called with non-tentative address " 1352 "%s(%s)\n", 1353 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr), 1354 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1355 goto done; 1356 } 1357 1358 /* timeouted with IFF_{RUNNING,UP} check */ 1359 if (dp->dad_ns_tcount > V_dad_maxtry) { 1360 nd6log((LOG_INFO, "%s: could not run DAD, driver problem?\n", 1361 if_name(ifa->ifa_ifp))); 1362 1363 TAILQ_REMOVE(&V_dadq, (struct dadq *)dp, dad_list); 1364 free(dp, M_IP6NDP); 1365 dp = NULL; 1366 ifa_free(ifa); 1367 goto done; 1368 } 1369 1370 /* Need more checks? */ 1371 if (dp->dad_ns_ocount < dp->dad_count) { 1372 /* 1373 * We have more NS to go. Send NS packet for DAD. 1374 */ 1375 nd6_dad_ns_output(dp, ifa); 1376 nd6_dad_starttimer(dp, 1377 (long)ND_IFINFO(ifa->ifa_ifp)->retrans * hz / 1000); 1378 } else { 1379 /* 1380 * We have transmitted sufficient number of DAD packets. 1381 * See what we've got. 1382 */ 1383 int duplicate; 1384 1385 duplicate = 0; 1386 1387 if (dp->dad_na_icount) { 1388 /* 1389 * the check is in nd6_dad_na_input(), 1390 * but just in case 1391 */ 1392 duplicate++; 1393 } 1394 1395 if (dp->dad_ns_icount) { 1396 /* We've seen NS, means DAD has failed. */ 1397 duplicate++; 1398 } 1399 1400 if (duplicate) { 1401 /* (*dp) will be freed in nd6_dad_duplicated() */ 1402 dp = NULL; 1403 nd6_dad_duplicated(ifa); 1404 } else { 1405 /* 1406 * We are done with DAD. No NA came, no NS came. 1407 * No duplicate address found. 1408 */ 1409 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1410 1411 nd6log((LOG_DEBUG, 1412 "%s: DAD complete for %s - no duplicates found\n", 1413 if_name(ifa->ifa_ifp), 1414 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr))); 1415 1416 TAILQ_REMOVE(&V_dadq, (struct dadq *)dp, dad_list); 1417 free(dp, M_IP6NDP); 1418 dp = NULL; 1419 ifa_free(ifa); 1420 } 1421 } 1422 1423 done: 1424 CURVNET_RESTORE(); 1425 } 1426 1427 void 1428 nd6_dad_duplicated(struct ifaddr *ifa) 1429 { 1430 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1431 struct ifnet *ifp; 1432 struct dadq *dp; 1433 char ip6buf[INET6_ADDRSTRLEN]; 1434 1435 dp = nd6_dad_find(ifa); 1436 if (dp == NULL) { 1437 log(LOG_ERR, "nd6_dad_duplicated: DAD structure not found\n"); 1438 return; 1439 } 1440 1441 log(LOG_ERR, "%s: DAD detected duplicate IPv6 address %s: " 1442 "NS in/out=%d/%d, NA in=%d\n", 1443 if_name(ifa->ifa_ifp), ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr), 1444 dp->dad_ns_icount, dp->dad_ns_ocount, dp->dad_na_icount); 1445 1446 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1447 ia->ia6_flags |= IN6_IFF_DUPLICATED; 1448 1449 /* We are done with DAD, with duplicate address found. (failure) */ 1450 nd6_dad_stoptimer(dp); 1451 1452 ifp = ifa->ifa_ifp; 1453 log(LOG_ERR, "%s: DAD complete for %s - duplicate found\n", 1454 if_name(ifp), ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr)); 1455 log(LOG_ERR, "%s: manual intervention required\n", 1456 if_name(ifp)); 1457 1458 /* 1459 * If the address is a link-local address formed from an interface 1460 * identifier based on the hardware address which is supposed to be 1461 * uniquely assigned (e.g., EUI-64 for an Ethernet interface), IP 1462 * operation on the interface SHOULD be disabled. 1463 * [RFC 4862, Section 5.4.5] 1464 */ 1465 if (IN6_IS_ADDR_LINKLOCAL(&ia->ia_addr.sin6_addr)) { 1466 struct in6_addr in6; 1467 1468 /* 1469 * To avoid over-reaction, we only apply this logic when we are 1470 * very sure that hardware addresses are supposed to be unique. 1471 */ 1472 switch (ifp->if_type) { 1473 case IFT_ETHER: 1474 case IFT_FDDI: 1475 case IFT_ATM: 1476 case IFT_IEEE1394: 1477 #ifdef IFT_IEEE80211 1478 case IFT_IEEE80211: 1479 #endif 1480 case IFT_INFINIBAND: 1481 in6 = ia->ia_addr.sin6_addr; 1482 if (in6_get_hw_ifid(ifp, &in6) == 0 && 1483 IN6_ARE_ADDR_EQUAL(&ia->ia_addr.sin6_addr, &in6)) { 1484 ND_IFINFO(ifp)->flags |= ND6_IFF_IFDISABLED; 1485 log(LOG_ERR, "%s: possible hardware address " 1486 "duplication detected, disable IPv6\n", 1487 if_name(ifp)); 1488 } 1489 break; 1490 } 1491 } 1492 1493 TAILQ_REMOVE(&V_dadq, (struct dadq *)dp, dad_list); 1494 free(dp, M_IP6NDP); 1495 dp = NULL; 1496 ifa_free(ifa); 1497 } 1498 1499 static void 1500 nd6_dad_ns_output(struct dadq *dp, struct ifaddr *ifa) 1501 { 1502 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1503 struct ifnet *ifp = ifa->ifa_ifp; 1504 1505 dp->dad_ns_tcount++; 1506 if ((ifp->if_flags & IFF_UP) == 0) { 1507 return; 1508 } 1509 if ((ifp->if_drv_flags & IFF_DRV_RUNNING) == 0) { 1510 return; 1511 } 1512 1513 dp->dad_ns_ocount++; 1514 nd6_ns_output(ifp, NULL, &ia->ia_addr.sin6_addr, NULL, 1); 1515 } 1516 1517 static void 1518 nd6_dad_ns_input(struct ifaddr *ifa) 1519 { 1520 struct in6_ifaddr *ia; 1521 struct ifnet *ifp; 1522 const struct in6_addr *taddr6; 1523 struct dadq *dp; 1524 int duplicate; 1525 1526 if (ifa == NULL) 1527 panic("ifa == NULL in nd6_dad_ns_input"); 1528 1529 ia = (struct in6_ifaddr *)ifa; 1530 ifp = ifa->ifa_ifp; 1531 taddr6 = &ia->ia_addr.sin6_addr; 1532 duplicate = 0; 1533 dp = nd6_dad_find(ifa); 1534 1535 /* Quickhack - completely ignore DAD NS packets */ 1536 if (V_dad_ignore_ns) { 1537 char ip6buf[INET6_ADDRSTRLEN]; 1538 nd6log((LOG_INFO, 1539 "nd6_dad_ns_input: ignoring DAD NS packet for " 1540 "address %s(%s)\n", ip6_sprintf(ip6buf, taddr6), 1541 if_name(ifa->ifa_ifp))); 1542 return; 1543 } 1544 1545 /* 1546 * if I'm yet to start DAD, someone else started using this address 1547 * first. I have a duplicate and you win. 1548 */ 1549 if (dp == NULL || dp->dad_ns_ocount == 0) 1550 duplicate++; 1551 1552 /* XXX more checks for loopback situation - see nd6_dad_timer too */ 1553 1554 if (duplicate) { 1555 dp = NULL; /* will be freed in nd6_dad_duplicated() */ 1556 nd6_dad_duplicated(ifa); 1557 } else { 1558 /* 1559 * not sure if I got a duplicate. 1560 * increment ns count and see what happens. 1561 */ 1562 if (dp) 1563 dp->dad_ns_icount++; 1564 } 1565 } 1566 1567 static void 1568 nd6_dad_na_input(struct ifaddr *ifa) 1569 { 1570 struct dadq *dp; 1571 1572 if (ifa == NULL) 1573 panic("ifa == NULL in nd6_dad_na_input"); 1574 1575 dp = nd6_dad_find(ifa); 1576 if (dp) 1577 dp->dad_na_icount++; 1578 1579 /* remove the address. */ 1580 nd6_dad_duplicated(ifa); 1581 } 1582