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 int rflag; 116 union nd_opts ndopts; 117 struct sockaddr_dl proxydl; 118 char ip6bufs[INET6_ADDRSTRLEN], ip6bufd[INET6_ADDRSTRLEN]; 119 120 rflag = (V_ip6_forwarding) ? ND_NA_FLAG_ROUTER : 0; 121 if (ND_IFINFO(ifp)->flags & ND6_IFF_ACCEPT_RTADV && V_ip6_norbit_raif) 122 rflag = 0; 123 #ifndef PULLDOWN_TEST 124 IP6_EXTHDR_CHECK(m, off, icmp6len,); 125 nd_ns = (struct nd_neighbor_solicit *)((caddr_t)ip6 + off); 126 #else 127 IP6_EXTHDR_GET(nd_ns, struct nd_neighbor_solicit *, m, off, icmp6len); 128 if (nd_ns == NULL) { 129 ICMP6STAT_INC(icp6s_tooshort); 130 return; 131 } 132 #endif 133 ip6 = mtod(m, struct ip6_hdr *); /* adjust pointer for safety */ 134 taddr6 = nd_ns->nd_ns_target; 135 if (in6_setscope(&taddr6, ifp, NULL) != 0) 136 goto bad; 137 138 if (ip6->ip6_hlim != 255) { 139 nd6log((LOG_ERR, 140 "nd6_ns_input: invalid hlim (%d) from %s to %s on %s\n", 141 ip6->ip6_hlim, ip6_sprintf(ip6bufs, &ip6->ip6_src), 142 ip6_sprintf(ip6bufd, &ip6->ip6_dst), if_name(ifp))); 143 goto bad; 144 } 145 146 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) { 147 /* dst has to be a solicited node multicast address. */ 148 if (daddr6.s6_addr16[0] == IPV6_ADDR_INT16_MLL && 149 /* don't check ifindex portion */ 150 daddr6.s6_addr32[1] == 0 && 151 daddr6.s6_addr32[2] == IPV6_ADDR_INT32_ONE && 152 daddr6.s6_addr8[12] == 0xff) { 153 ; /* good */ 154 } else { 155 nd6log((LOG_INFO, "nd6_ns_input: bad DAD packet " 156 "(wrong ip6 dst)\n")); 157 goto bad; 158 } 159 } else if (!V_nd6_onlink_ns_rfc4861) { 160 struct sockaddr_in6 src_sa6; 161 162 /* 163 * According to recent IETF discussions, it is not a good idea 164 * to accept a NS from an address which would not be deemed 165 * to be a neighbor otherwise. This point is expected to be 166 * clarified in future revisions of the specification. 167 */ 168 bzero(&src_sa6, sizeof(src_sa6)); 169 src_sa6.sin6_family = AF_INET6; 170 src_sa6.sin6_len = sizeof(src_sa6); 171 src_sa6.sin6_addr = saddr6; 172 if (nd6_is_addr_neighbor(&src_sa6, ifp) == 0) { 173 nd6log((LOG_INFO, "nd6_ns_input: " 174 "NS packet from non-neighbor\n")); 175 goto bad; 176 } 177 } 178 179 if (IN6_IS_ADDR_MULTICAST(&taddr6)) { 180 nd6log((LOG_INFO, "nd6_ns_input: bad NS target (multicast)\n")); 181 goto bad; 182 } 183 184 icmp6len -= sizeof(*nd_ns); 185 nd6_option_init(nd_ns + 1, icmp6len, &ndopts); 186 if (nd6_options(&ndopts) < 0) { 187 nd6log((LOG_INFO, 188 "nd6_ns_input: invalid ND option, ignored\n")); 189 /* nd6_options have incremented stats */ 190 goto freeit; 191 } 192 193 if (ndopts.nd_opts_src_lladdr) { 194 lladdr = (char *)(ndopts.nd_opts_src_lladdr + 1); 195 lladdrlen = ndopts.nd_opts_src_lladdr->nd_opt_len << 3; 196 } 197 198 if (IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_src) && lladdr) { 199 nd6log((LOG_INFO, "nd6_ns_input: bad DAD packet " 200 "(link-layer address option)\n")); 201 goto bad; 202 } 203 204 /* 205 * Attaching target link-layer address to the NA? 206 * (RFC 2461 7.2.4) 207 * 208 * NS IP dst is unicast/anycast MUST NOT add 209 * NS IP dst is solicited-node multicast MUST add 210 * 211 * In implementation, we add target link-layer address by default. 212 * We do not add one in MUST NOT cases. 213 */ 214 if (!IN6_IS_ADDR_MULTICAST(&daddr6)) 215 tlladdr = 0; 216 else 217 tlladdr = 1; 218 219 /* 220 * Target address (taddr6) must be either: 221 * (1) Valid unicast/anycast address for my receiving interface, 222 * (2) Unicast address for which I'm offering proxy service, or 223 * (3) "tentative" address on which DAD is being performed. 224 */ 225 /* (1) and (3) check. */ 226 if (ifp->if_carp) 227 ifa = (*carp_iamatch6_p)(ifp, &taddr6); 228 else 229 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &taddr6); 230 231 /* (2) check. */ 232 if (ifa == NULL) { 233 struct rtentry *rt; 234 struct sockaddr_in6 tsin6; 235 int need_proxy; 236 #ifdef RADIX_MPATH 237 struct route_in6 ro; 238 #endif 239 240 bzero(&tsin6, sizeof tsin6); 241 tsin6.sin6_len = sizeof(struct sockaddr_in6); 242 tsin6.sin6_family = AF_INET6; 243 tsin6.sin6_addr = taddr6; 244 245 #ifdef RADIX_MPATH 246 bzero(&ro, sizeof(ro)); 247 ro.ro_dst = tsin6; 248 rtalloc_mpath((struct route *)&ro, RTF_ANNOUNCE); 249 rt = ro.ro_rt; 250 #else 251 rt = rtalloc1((struct sockaddr *)&tsin6, 0, 0); 252 #endif 253 need_proxy = (rt && (rt->rt_flags & RTF_ANNOUNCE) != 0 && 254 rt->rt_gateway->sa_family == AF_LINK); 255 if (rt != NULL) { 256 /* 257 * Make a copy while we can be sure that rt_gateway 258 * is still stable before unlocking to avoid lock 259 * order problems. proxydl will only be used if 260 * proxy will be set in the next block. 261 */ 262 if (need_proxy) 263 proxydl = *SDL(rt->rt_gateway); 264 RTFREE_LOCKED(rt); 265 } 266 if (need_proxy) { 267 /* 268 * proxy NDP for single entry 269 */ 270 ifa = (struct ifaddr *)in6ifa_ifpforlinklocal(ifp, 271 IN6_IFF_NOTREADY|IN6_IFF_ANYCAST); 272 if (ifa) 273 proxy = 1; 274 } 275 } 276 if (ifa == NULL) { 277 /* 278 * We've got an NS packet, and we don't have that adddress 279 * assigned for us. We MUST silently ignore it. 280 * See RFC2461 7.2.3. 281 */ 282 goto freeit; 283 } 284 myaddr6 = *IFA_IN6(ifa); 285 anycast = ((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_ANYCAST; 286 tentative = ((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_TENTATIVE; 287 if (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_DUPLICATED) 288 goto freeit; 289 290 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) { 291 nd6log((LOG_INFO, "nd6_ns_input: lladdrlen mismatch for %s " 292 "(if %d, NS packet %d)\n", 293 ip6_sprintf(ip6bufs, &taddr6), 294 ifp->if_addrlen, lladdrlen - 2)); 295 goto bad; 296 } 297 298 if (IN6_ARE_ADDR_EQUAL(&myaddr6, &saddr6)) { 299 nd6log((LOG_INFO, "nd6_ns_input: duplicate IP6 address %s\n", 300 ip6_sprintf(ip6bufs, &saddr6))); 301 goto freeit; 302 } 303 304 /* 305 * We have neighbor solicitation packet, with target address equals to 306 * one of my tentative address. 307 * 308 * src addr how to process? 309 * --- --- 310 * multicast of course, invalid (rejected in ip6_input) 311 * unicast somebody is doing address resolution -> ignore 312 * unspec dup address detection 313 * 314 * The processing is defined in RFC 2462. 315 */ 316 if (tentative) { 317 /* 318 * If source address is unspecified address, it is for 319 * duplicate address detection. 320 * 321 * If not, the packet is for addess resolution; 322 * silently ignore it. 323 */ 324 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) 325 nd6_dad_ns_input(ifa); 326 327 goto freeit; 328 } 329 330 /* 331 * If the source address is unspecified address, entries must not 332 * be created or updated. 333 * It looks that sender is performing DAD. Output NA toward 334 * all-node multicast address, to tell the sender that I'm using 335 * the address. 336 * S bit ("solicited") must be zero. 337 */ 338 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) { 339 struct in6_addr in6_all; 340 341 in6_all = in6addr_linklocal_allnodes; 342 if (in6_setscope(&in6_all, ifp, NULL) != 0) 343 goto bad; 344 nd6_na_output(ifp, &in6_all, &taddr6, 345 ((anycast || proxy || !tlladdr) ? 0 : ND_NA_FLAG_OVERRIDE) | 346 rflag, tlladdr, proxy ? (struct sockaddr *)&proxydl : NULL); 347 goto freeit; 348 } 349 350 nd6_cache_lladdr(ifp, &saddr6, lladdr, lladdrlen, 351 ND_NEIGHBOR_SOLICIT, 0); 352 353 nd6_na_output(ifp, &saddr6, &taddr6, 354 ((anycast || proxy || !tlladdr) ? 0 : ND_NA_FLAG_OVERRIDE) | 355 rflag | ND_NA_FLAG_SOLICITED, tlladdr, 356 proxy ? (struct sockaddr *)&proxydl : NULL); 357 freeit: 358 if (ifa != NULL) 359 ifa_free(ifa); 360 m_freem(m); 361 return; 362 363 bad: 364 nd6log((LOG_ERR, "nd6_ns_input: src=%s\n", 365 ip6_sprintf(ip6bufs, &saddr6))); 366 nd6log((LOG_ERR, "nd6_ns_input: dst=%s\n", 367 ip6_sprintf(ip6bufs, &daddr6))); 368 nd6log((LOG_ERR, "nd6_ns_input: tgt=%s\n", 369 ip6_sprintf(ip6bufs, &taddr6))); 370 ICMP6STAT_INC(icp6s_badns); 371 if (ifa != NULL) 372 ifa_free(ifa); 373 m_freem(m); 374 } 375 376 /* 377 * Output a Neighbor Solicitation Message. Caller specifies: 378 * - ICMP6 header source IP6 address 379 * - ND6 header target IP6 address 380 * - ND6 header source datalink address 381 * 382 * Based on RFC 2461 383 * Based on RFC 2462 (duplicate address detection) 384 * 385 * ln - for source address determination 386 * dad - duplicate address detection 387 */ 388 void 389 nd6_ns_output(struct ifnet *ifp, const struct in6_addr *daddr6, 390 const struct in6_addr *taddr6, struct llentry *ln, int dad) 391 { 392 struct mbuf *m; 393 struct m_tag *mtag; 394 struct ip6_hdr *ip6; 395 struct nd_neighbor_solicit *nd_ns; 396 struct ip6_moptions im6o; 397 int icmp6len; 398 int maxlen; 399 caddr_t mac; 400 struct route_in6 ro; 401 402 if (IN6_IS_ADDR_MULTICAST(taddr6)) 403 return; 404 405 /* estimate the size of message */ 406 maxlen = sizeof(*ip6) + sizeof(*nd_ns); 407 maxlen += (sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7; 408 if (max_linkhdr + maxlen >= MCLBYTES) { 409 #ifdef DIAGNOSTIC 410 printf("nd6_ns_output: max_linkhdr + maxlen >= MCLBYTES " 411 "(%d + %d > %d)\n", max_linkhdr, maxlen, MCLBYTES); 412 #endif 413 return; 414 } 415 416 MGETHDR(m, M_DONTWAIT, MT_DATA); 417 if (m && max_linkhdr + maxlen >= MHLEN) { 418 MCLGET(m, M_DONTWAIT); 419 if ((m->m_flags & M_EXT) == 0) { 420 m_free(m); 421 m = NULL; 422 } 423 } 424 if (m == NULL) 425 return; 426 m->m_pkthdr.rcvif = NULL; 427 428 bzero(&ro, sizeof(ro)); 429 430 if (daddr6 == NULL || IN6_IS_ADDR_MULTICAST(daddr6)) { 431 m->m_flags |= M_MCAST; 432 im6o.im6o_multicast_ifp = ifp; 433 im6o.im6o_multicast_hlim = 255; 434 im6o.im6o_multicast_loop = 0; 435 } 436 437 icmp6len = sizeof(*nd_ns); 438 m->m_pkthdr.len = m->m_len = sizeof(*ip6) + icmp6len; 439 m->m_data += max_linkhdr; /* or MH_ALIGN() equivalent? */ 440 441 /* fill neighbor solicitation packet */ 442 ip6 = mtod(m, struct ip6_hdr *); 443 ip6->ip6_flow = 0; 444 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 445 ip6->ip6_vfc |= IPV6_VERSION; 446 /* ip6->ip6_plen will be set later */ 447 ip6->ip6_nxt = IPPROTO_ICMPV6; 448 ip6->ip6_hlim = 255; 449 if (daddr6) 450 ip6->ip6_dst = *daddr6; 451 else { 452 ip6->ip6_dst.s6_addr16[0] = IPV6_ADDR_INT16_MLL; 453 ip6->ip6_dst.s6_addr16[1] = 0; 454 ip6->ip6_dst.s6_addr32[1] = 0; 455 ip6->ip6_dst.s6_addr32[2] = IPV6_ADDR_INT32_ONE; 456 ip6->ip6_dst.s6_addr32[3] = taddr6->s6_addr32[3]; 457 ip6->ip6_dst.s6_addr8[12] = 0xff; 458 if (in6_setscope(&ip6->ip6_dst, ifp, NULL) != 0) 459 goto bad; 460 } 461 if (!dad) { 462 struct ifaddr *ifa; 463 464 /* 465 * RFC2461 7.2.2: 466 * "If the source address of the packet prompting the 467 * solicitation is the same as one of the addresses assigned 468 * to the outgoing interface, that address SHOULD be placed 469 * in the IP Source Address of the outgoing solicitation. 470 * Otherwise, any one of the addresses assigned to the 471 * interface should be used." 472 * 473 * We use the source address for the prompting packet 474 * (saddr6), if: 475 * - saddr6 is given from the caller (by giving "ln"), and 476 * - saddr6 belongs to the outgoing interface. 477 * Otherwise, we perform the source address selection as usual. 478 */ 479 struct in6_addr *hsrc; 480 481 hsrc = NULL; 482 if (ln != NULL) { 483 LLE_RLOCK(ln); 484 if (ln->la_hold != NULL) { 485 struct ip6_hdr *hip6; /* hold ip6 */ 486 487 /* 488 * assuming every packet in la_hold has the same IP 489 * header 490 */ 491 hip6 = mtod(ln->la_hold, struct ip6_hdr *); 492 /* XXX pullup? */ 493 if (sizeof(*hip6) < ln->la_hold->m_len) { 494 ip6->ip6_src = hip6->ip6_src; 495 hsrc = &hip6->ip6_src; 496 } 497 } 498 LLE_RUNLOCK(ln); 499 } 500 if (hsrc && (ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, 501 hsrc)) != NULL) { 502 /* ip6_src set already. */ 503 ifa_free(ifa); 504 } else { 505 int error; 506 struct sockaddr_in6 dst_sa; 507 struct in6_addr src_in; 508 509 bzero(&dst_sa, sizeof(dst_sa)); 510 dst_sa.sin6_family = AF_INET6; 511 dst_sa.sin6_len = sizeof(dst_sa); 512 dst_sa.sin6_addr = ip6->ip6_dst; 513 514 error = in6_selectsrc(&dst_sa, NULL, 515 NULL, &ro, NULL, NULL, &src_in); 516 if (error) { 517 char ip6buf[INET6_ADDRSTRLEN]; 518 nd6log((LOG_DEBUG, 519 "nd6_ns_output: source can't be " 520 "determined: dst=%s, error=%d\n", 521 ip6_sprintf(ip6buf, &dst_sa.sin6_addr), 522 error)); 523 goto bad; 524 } 525 ip6->ip6_src = src_in; 526 } 527 } else { 528 /* 529 * Source address for DAD packet must always be IPv6 530 * unspecified address. (0::0) 531 * We actually don't have to 0-clear the address (we did it 532 * above), but we do so here explicitly to make the intention 533 * clearer. 534 */ 535 bzero(&ip6->ip6_src, sizeof(ip6->ip6_src)); 536 } 537 nd_ns = (struct nd_neighbor_solicit *)(ip6 + 1); 538 nd_ns->nd_ns_type = ND_NEIGHBOR_SOLICIT; 539 nd_ns->nd_ns_code = 0; 540 nd_ns->nd_ns_reserved = 0; 541 nd_ns->nd_ns_target = *taddr6; 542 in6_clearscope(&nd_ns->nd_ns_target); /* XXX */ 543 544 /* 545 * Add source link-layer address option. 546 * 547 * spec implementation 548 * --- --- 549 * DAD packet MUST NOT do not add the option 550 * there's no link layer address: 551 * impossible do not add the option 552 * there's link layer address: 553 * Multicast NS MUST add one add the option 554 * Unicast NS SHOULD add one add the option 555 */ 556 if (!dad && (mac = nd6_ifptomac(ifp))) { 557 int optlen = sizeof(struct nd_opt_hdr) + ifp->if_addrlen; 558 struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)(nd_ns + 1); 559 /* 8 byte alignments... */ 560 optlen = (optlen + 7) & ~7; 561 562 m->m_pkthdr.len += optlen; 563 m->m_len += optlen; 564 icmp6len += optlen; 565 bzero((caddr_t)nd_opt, optlen); 566 nd_opt->nd_opt_type = ND_OPT_SOURCE_LINKADDR; 567 nd_opt->nd_opt_len = optlen >> 3; 568 bcopy(mac, (caddr_t)(nd_opt + 1), ifp->if_addrlen); 569 } 570 571 ip6->ip6_plen = htons((u_short)icmp6len); 572 nd_ns->nd_ns_cksum = 0; 573 nd_ns->nd_ns_cksum = 574 in6_cksum(m, IPPROTO_ICMPV6, sizeof(*ip6), icmp6len); 575 576 if (send_sendso_input_hook != NULL) { 577 mtag = m_tag_get(PACKET_TAG_ND_OUTGOING, 578 sizeof(unsigned short), M_NOWAIT); 579 if (mtag == NULL) 580 goto bad; 581 *(unsigned short *)(mtag + 1) = nd_ns->nd_ns_type; 582 m_tag_prepend(m, mtag); 583 } 584 585 ip6_output(m, NULL, &ro, dad ? IPV6_UNSPECSRC : 0, &im6o, NULL, NULL); 586 icmp6_ifstat_inc(ifp, ifs6_out_msg); 587 icmp6_ifstat_inc(ifp, ifs6_out_neighborsolicit); 588 ICMP6STAT_INC(icp6s_outhist[ND_NEIGHBOR_SOLICIT]); 589 590 if (ro.ro_rt) { /* we don't cache this route. */ 591 RTFREE(ro.ro_rt); 592 } 593 return; 594 595 bad: 596 if (ro.ro_rt) { 597 RTFREE(ro.ro_rt); 598 } 599 m_freem(m); 600 return; 601 } 602 603 /* 604 * Neighbor advertisement input handling. 605 * 606 * Based on RFC 2461 607 * Based on RFC 2462 (duplicate address detection) 608 * 609 * the following items are not implemented yet: 610 * - proxy advertisement delay rule (RFC2461 7.2.8, last paragraph, SHOULD) 611 * - anycast advertisement delay rule (RFC2461 7.2.7, SHOULD) 612 */ 613 void 614 nd6_na_input(struct mbuf *m, int off, int icmp6len) 615 { 616 struct ifnet *ifp = m->m_pkthdr.rcvif; 617 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 618 struct nd_neighbor_advert *nd_na; 619 struct in6_addr daddr6 = ip6->ip6_dst; 620 struct in6_addr taddr6; 621 int flags; 622 int is_router; 623 int is_solicited; 624 int is_override; 625 char *lladdr = NULL; 626 int lladdrlen = 0; 627 int checklink = 0; 628 struct ifaddr *ifa; 629 struct llentry *ln = NULL; 630 union nd_opts ndopts; 631 struct mbuf *chain = NULL; 632 struct m_tag *mtag; 633 struct sockaddr_in6 sin6; 634 char ip6bufs[INET6_ADDRSTRLEN], ip6bufd[INET6_ADDRSTRLEN]; 635 636 if (ip6->ip6_hlim != 255) { 637 nd6log((LOG_ERR, 638 "nd6_na_input: invalid hlim (%d) from %s to %s on %s\n", 639 ip6->ip6_hlim, ip6_sprintf(ip6bufs, &ip6->ip6_src), 640 ip6_sprintf(ip6bufd, &ip6->ip6_dst), if_name(ifp))); 641 goto bad; 642 } 643 644 #ifndef PULLDOWN_TEST 645 IP6_EXTHDR_CHECK(m, off, icmp6len,); 646 nd_na = (struct nd_neighbor_advert *)((caddr_t)ip6 + off); 647 #else 648 IP6_EXTHDR_GET(nd_na, struct nd_neighbor_advert *, m, off, icmp6len); 649 if (nd_na == NULL) { 650 ICMP6STAT_INC(icp6s_tooshort); 651 return; 652 } 653 #endif 654 655 flags = nd_na->nd_na_flags_reserved; 656 is_router = ((flags & ND_NA_FLAG_ROUTER) != 0); 657 is_solicited = ((flags & ND_NA_FLAG_SOLICITED) != 0); 658 is_override = ((flags & ND_NA_FLAG_OVERRIDE) != 0); 659 660 taddr6 = nd_na->nd_na_target; 661 if (in6_setscope(&taddr6, ifp, NULL)) 662 goto bad; /* XXX: impossible */ 663 664 if (IN6_IS_ADDR_MULTICAST(&taddr6)) { 665 nd6log((LOG_ERR, 666 "nd6_na_input: invalid target address %s\n", 667 ip6_sprintf(ip6bufs, &taddr6))); 668 goto bad; 669 } 670 if (IN6_IS_ADDR_MULTICAST(&daddr6)) 671 if (is_solicited) { 672 nd6log((LOG_ERR, 673 "nd6_na_input: a solicited adv is multicasted\n")); 674 goto bad; 675 } 676 677 icmp6len -= sizeof(*nd_na); 678 nd6_option_init(nd_na + 1, icmp6len, &ndopts); 679 if (nd6_options(&ndopts) < 0) { 680 nd6log((LOG_INFO, 681 "nd6_na_input: invalid ND option, ignored\n")); 682 /* nd6_options have incremented stats */ 683 goto freeit; 684 } 685 686 if (ndopts.nd_opts_tgt_lladdr) { 687 lladdr = (char *)(ndopts.nd_opts_tgt_lladdr + 1); 688 lladdrlen = ndopts.nd_opts_tgt_lladdr->nd_opt_len << 3; 689 } 690 691 /* 692 * This effectively disables the DAD check on a non-master CARP 693 * address. 694 */ 695 if (ifp->if_carp) 696 ifa = (*carp_iamatch6_p)(ifp, &taddr6); 697 else 698 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &taddr6); 699 700 /* 701 * Target address matches one of my interface address. 702 * 703 * If my address is tentative, this means that there's somebody 704 * already using the same address as mine. This indicates DAD failure. 705 * This is defined in RFC 2462. 706 * 707 * Otherwise, process as defined in RFC 2461. 708 */ 709 if (ifa 710 && (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_TENTATIVE)) { 711 ifa_free(ifa); 712 nd6_dad_na_input(ifa); 713 goto freeit; 714 } 715 716 /* Just for safety, maybe unnecessary. */ 717 if (ifa) { 718 ifa_free(ifa); 719 log(LOG_ERR, 720 "nd6_na_input: duplicate IP6 address %s\n", 721 ip6_sprintf(ip6bufs, &taddr6)); 722 goto freeit; 723 } 724 725 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) { 726 nd6log((LOG_INFO, "nd6_na_input: lladdrlen mismatch for %s " 727 "(if %d, NA packet %d)\n", ip6_sprintf(ip6bufs, &taddr6), 728 ifp->if_addrlen, lladdrlen - 2)); 729 goto bad; 730 } 731 732 /* 733 * If no neighbor cache entry is found, NA SHOULD silently be 734 * discarded. 735 */ 736 IF_AFDATA_LOCK(ifp); 737 ln = nd6_lookup(&taddr6, LLE_EXCLUSIVE, ifp); 738 IF_AFDATA_UNLOCK(ifp); 739 if (ln == NULL) { 740 goto freeit; 741 } 742 743 if (ln->ln_state == ND6_LLINFO_INCOMPLETE) { 744 /* 745 * If the link-layer has address, and no lladdr option came, 746 * discard the packet. 747 */ 748 if (ifp->if_addrlen && lladdr == NULL) { 749 goto freeit; 750 } 751 752 /* 753 * Record link-layer address, and update the state. 754 */ 755 bcopy(lladdr, &ln->ll_addr, ifp->if_addrlen); 756 ln->la_flags |= LLE_VALID; 757 if (is_solicited) { 758 ln->ln_state = ND6_LLINFO_REACHABLE; 759 ln->ln_byhint = 0; 760 if (!ND6_LLINFO_PERMANENT(ln)) { 761 nd6_llinfo_settimer_locked(ln, 762 (long)ND_IFINFO(ln->lle_tbl->llt_ifp)->reachable * hz); 763 } 764 } else { 765 ln->ln_state = ND6_LLINFO_STALE; 766 nd6_llinfo_settimer_locked(ln, (long)V_nd6_gctimer * hz); 767 } 768 if ((ln->ln_router = is_router) != 0) { 769 /* 770 * This means a router's state has changed from 771 * non-reachable to probably reachable, and might 772 * affect the status of associated prefixes.. 773 */ 774 checklink = 1; 775 } 776 } else { 777 int llchange; 778 779 /* 780 * Check if the link-layer address has changed or not. 781 */ 782 if (lladdr == NULL) 783 llchange = 0; 784 else { 785 if (ln->la_flags & LLE_VALID) { 786 if (bcmp(lladdr, &ln->ll_addr, ifp->if_addrlen)) 787 llchange = 1; 788 else 789 llchange = 0; 790 } else 791 llchange = 1; 792 } 793 794 /* 795 * This is VERY complex. Look at it with care. 796 * 797 * override solicit lladdr llchange action 798 * (L: record lladdr) 799 * 800 * 0 0 n -- (2c) 801 * 0 0 y n (2b) L 802 * 0 0 y y (1) REACHABLE->STALE 803 * 0 1 n -- (2c) *->REACHABLE 804 * 0 1 y n (2b) L *->REACHABLE 805 * 0 1 y y (1) REACHABLE->STALE 806 * 1 0 n -- (2a) 807 * 1 0 y n (2a) L 808 * 1 0 y y (2a) L *->STALE 809 * 1 1 n -- (2a) *->REACHABLE 810 * 1 1 y n (2a) L *->REACHABLE 811 * 1 1 y y (2a) L *->REACHABLE 812 */ 813 if (!is_override && (lladdr != NULL && llchange)) { /* (1) */ 814 /* 815 * If state is REACHABLE, make it STALE. 816 * no other updates should be done. 817 */ 818 if (ln->ln_state == ND6_LLINFO_REACHABLE) { 819 ln->ln_state = ND6_LLINFO_STALE; 820 nd6_llinfo_settimer_locked(ln, (long)V_nd6_gctimer * hz); 821 } 822 goto freeit; 823 } else if (is_override /* (2a) */ 824 || (!is_override && (lladdr != NULL && !llchange)) /* (2b) */ 825 || lladdr == NULL) { /* (2c) */ 826 /* 827 * Update link-local address, if any. 828 */ 829 if (lladdr != NULL) { 830 bcopy(lladdr, &ln->ll_addr, ifp->if_addrlen); 831 ln->la_flags |= LLE_VALID; 832 } 833 834 /* 835 * If solicited, make the state REACHABLE. 836 * If not solicited and the link-layer address was 837 * changed, make it STALE. 838 */ 839 if (is_solicited) { 840 ln->ln_state = ND6_LLINFO_REACHABLE; 841 ln->ln_byhint = 0; 842 if (!ND6_LLINFO_PERMANENT(ln)) { 843 nd6_llinfo_settimer_locked(ln, 844 (long)ND_IFINFO(ifp)->reachable * hz); 845 } 846 } else { 847 if (lladdr != NULL && llchange) { 848 ln->ln_state = ND6_LLINFO_STALE; 849 nd6_llinfo_settimer_locked(ln, 850 (long)V_nd6_gctimer * hz); 851 } 852 } 853 } 854 855 if (ln->ln_router && !is_router) { 856 /* 857 * The peer dropped the router flag. 858 * Remove the sender from the Default Router List and 859 * update the Destination Cache entries. 860 */ 861 struct nd_defrouter *dr; 862 struct in6_addr *in6; 863 864 in6 = &L3_ADDR_SIN6(ln)->sin6_addr; 865 866 /* 867 * Lock to protect the default router list. 868 * XXX: this might be unnecessary, since this function 869 * is only called under the network software interrupt 870 * context. However, we keep it just for safety. 871 */ 872 dr = defrouter_lookup(in6, ln->lle_tbl->llt_ifp); 873 if (dr) 874 defrtrlist_del(dr); 875 else if (ND_IFINFO(ln->lle_tbl->llt_ifp)->flags & 876 ND6_IFF_ACCEPT_RTADV) { 877 /* 878 * Even if the neighbor is not in the default 879 * router list, the neighbor may be used 880 * as a next hop for some destinations 881 * (e.g. redirect case). So we must 882 * call rt6_flush explicitly. 883 */ 884 rt6_flush(&ip6->ip6_src, ifp); 885 } 886 } 887 ln->ln_router = is_router; 888 } 889 /* XXX - QL 890 * Does this matter? 891 * rt->rt_flags &= ~RTF_REJECT; 892 */ 893 ln->la_asked = 0; 894 if (ln->la_hold) { 895 struct mbuf *m_hold, *m_hold_next; 896 897 /* 898 * reset the la_hold in advance, to explicitly 899 * prevent a la_hold lookup in nd6_output() 900 * (wouldn't happen, though...) 901 */ 902 for (m_hold = ln->la_hold, ln->la_hold = NULL; 903 m_hold; m_hold = m_hold_next) { 904 m_hold_next = m_hold->m_nextpkt; 905 m_hold->m_nextpkt = NULL; 906 /* 907 * we assume ifp is not a loopback here, so just set 908 * the 2nd argument as the 1st one. 909 */ 910 911 if (send_sendso_input_hook != NULL) { 912 mtag = m_tag_get(PACKET_TAG_ND_OUTGOING, 913 sizeof(unsigned short), M_NOWAIT); 914 if (mtag == NULL) 915 goto bad; 916 m_tag_prepend(m, mtag); 917 } 918 919 nd6_output_lle(ifp, ifp, m_hold, L3_ADDR_SIN6(ln), NULL, ln, &chain); 920 } 921 } 922 freeit: 923 if (ln != NULL) { 924 if (chain) 925 memcpy(&sin6, L3_ADDR_SIN6(ln), sizeof(sin6)); 926 LLE_WUNLOCK(ln); 927 928 if (chain) 929 nd6_output_flush(ifp, ifp, chain, &sin6, NULL); 930 } 931 if (checklink) 932 pfxlist_onlink_check(); 933 934 m_freem(m); 935 return; 936 937 bad: 938 if (ln != NULL) 939 LLE_WUNLOCK(ln); 940 941 ICMP6STAT_INC(icp6s_badna); 942 m_freem(m); 943 } 944 945 /* 946 * Neighbor advertisement output handling. 947 * 948 * Based on RFC 2461 949 * 950 * the following items are not implemented yet: 951 * - proxy advertisement delay rule (RFC2461 7.2.8, last paragraph, SHOULD) 952 * - anycast advertisement delay rule (RFC2461 7.2.7, SHOULD) 953 * 954 * tlladdr - 1 if include target link-layer address 955 * sdl0 - sockaddr_dl (= proxy NA) or NULL 956 */ 957 void 958 nd6_na_output(struct ifnet *ifp, const struct in6_addr *daddr6_0, 959 const struct in6_addr *taddr6, u_long flags, int tlladdr, 960 struct sockaddr *sdl0) 961 { 962 struct mbuf *m; 963 struct m_tag *mtag; 964 struct ip6_hdr *ip6; 965 struct nd_neighbor_advert *nd_na; 966 struct ip6_moptions im6o; 967 struct in6_addr src, daddr6; 968 struct sockaddr_in6 dst_sa; 969 int icmp6len, maxlen, error; 970 caddr_t mac = NULL; 971 struct route_in6 ro; 972 973 bzero(&ro, sizeof(ro)); 974 975 daddr6 = *daddr6_0; /* make a local copy for modification */ 976 977 /* estimate the size of message */ 978 maxlen = sizeof(*ip6) + sizeof(*nd_na); 979 maxlen += (sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7; 980 if (max_linkhdr + maxlen >= MCLBYTES) { 981 #ifdef DIAGNOSTIC 982 printf("nd6_na_output: max_linkhdr + maxlen >= MCLBYTES " 983 "(%d + %d > %d)\n", max_linkhdr, maxlen, MCLBYTES); 984 #endif 985 return; 986 } 987 988 MGETHDR(m, M_DONTWAIT, MT_DATA); 989 if (m && max_linkhdr + maxlen >= MHLEN) { 990 MCLGET(m, M_DONTWAIT); 991 if ((m->m_flags & M_EXT) == 0) { 992 m_free(m); 993 m = NULL; 994 } 995 } 996 if (m == NULL) 997 return; 998 m->m_pkthdr.rcvif = NULL; 999 1000 if (IN6_IS_ADDR_MULTICAST(&daddr6)) { 1001 m->m_flags |= M_MCAST; 1002 im6o.im6o_multicast_ifp = ifp; 1003 im6o.im6o_multicast_hlim = 255; 1004 im6o.im6o_multicast_loop = 0; 1005 } 1006 1007 icmp6len = sizeof(*nd_na); 1008 m->m_pkthdr.len = m->m_len = sizeof(struct ip6_hdr) + icmp6len; 1009 m->m_data += max_linkhdr; /* or MH_ALIGN() equivalent? */ 1010 1011 /* fill neighbor advertisement packet */ 1012 ip6 = mtod(m, struct ip6_hdr *); 1013 ip6->ip6_flow = 0; 1014 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 1015 ip6->ip6_vfc |= IPV6_VERSION; 1016 ip6->ip6_nxt = IPPROTO_ICMPV6; 1017 ip6->ip6_hlim = 255; 1018 if (IN6_IS_ADDR_UNSPECIFIED(&daddr6)) { 1019 /* reply to DAD */ 1020 daddr6.s6_addr16[0] = IPV6_ADDR_INT16_MLL; 1021 daddr6.s6_addr16[1] = 0; 1022 daddr6.s6_addr32[1] = 0; 1023 daddr6.s6_addr32[2] = 0; 1024 daddr6.s6_addr32[3] = IPV6_ADDR_INT32_ONE; 1025 if (in6_setscope(&daddr6, ifp, NULL)) 1026 goto bad; 1027 1028 flags &= ~ND_NA_FLAG_SOLICITED; 1029 } 1030 ip6->ip6_dst = daddr6; 1031 bzero(&dst_sa, sizeof(struct sockaddr_in6)); 1032 dst_sa.sin6_family = AF_INET6; 1033 dst_sa.sin6_len = sizeof(struct sockaddr_in6); 1034 dst_sa.sin6_addr = daddr6; 1035 1036 /* 1037 * Select a source whose scope is the same as that of the dest. 1038 */ 1039 bcopy(&dst_sa, &ro.ro_dst, sizeof(dst_sa)); 1040 error = in6_selectsrc(&dst_sa, NULL, NULL, &ro, NULL, NULL, &src); 1041 if (error) { 1042 char ip6buf[INET6_ADDRSTRLEN]; 1043 nd6log((LOG_DEBUG, "nd6_na_output: source can't be " 1044 "determined: dst=%s, error=%d\n", 1045 ip6_sprintf(ip6buf, &dst_sa.sin6_addr), error)); 1046 goto bad; 1047 } 1048 ip6->ip6_src = src; 1049 nd_na = (struct nd_neighbor_advert *)(ip6 + 1); 1050 nd_na->nd_na_type = ND_NEIGHBOR_ADVERT; 1051 nd_na->nd_na_code = 0; 1052 nd_na->nd_na_target = *taddr6; 1053 in6_clearscope(&nd_na->nd_na_target); /* XXX */ 1054 1055 /* 1056 * "tlladdr" indicates NS's condition for adding tlladdr or not. 1057 * see nd6_ns_input() for details. 1058 * Basically, if NS packet is sent to unicast/anycast addr, 1059 * target lladdr option SHOULD NOT be included. 1060 */ 1061 if (tlladdr) { 1062 /* 1063 * sdl0 != NULL indicates proxy NA. If we do proxy, use 1064 * lladdr in sdl0. If we are not proxying (sending NA for 1065 * my address) use lladdr configured for the interface. 1066 */ 1067 if (sdl0 == NULL) { 1068 if (ifp->if_carp) 1069 mac = (*carp_macmatch6_p)(ifp, m, taddr6); 1070 if (mac == NULL) 1071 mac = nd6_ifptomac(ifp); 1072 } else if (sdl0->sa_family == AF_LINK) { 1073 struct sockaddr_dl *sdl; 1074 sdl = (struct sockaddr_dl *)sdl0; 1075 if (sdl->sdl_alen == ifp->if_addrlen) 1076 mac = LLADDR(sdl); 1077 } 1078 } 1079 if (tlladdr && mac) { 1080 int optlen = sizeof(struct nd_opt_hdr) + ifp->if_addrlen; 1081 struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)(nd_na + 1); 1082 1083 /* roundup to 8 bytes alignment! */ 1084 optlen = (optlen + 7) & ~7; 1085 1086 m->m_pkthdr.len += optlen; 1087 m->m_len += optlen; 1088 icmp6len += optlen; 1089 bzero((caddr_t)nd_opt, optlen); 1090 nd_opt->nd_opt_type = ND_OPT_TARGET_LINKADDR; 1091 nd_opt->nd_opt_len = optlen >> 3; 1092 bcopy(mac, (caddr_t)(nd_opt + 1), ifp->if_addrlen); 1093 } else 1094 flags &= ~ND_NA_FLAG_OVERRIDE; 1095 1096 ip6->ip6_plen = htons((u_short)icmp6len); 1097 nd_na->nd_na_flags_reserved = flags; 1098 nd_na->nd_na_cksum = 0; 1099 nd_na->nd_na_cksum = 1100 in6_cksum(m, IPPROTO_ICMPV6, sizeof(struct ip6_hdr), icmp6len); 1101 1102 if (send_sendso_input_hook != NULL) { 1103 mtag = m_tag_get(PACKET_TAG_ND_OUTGOING, 1104 sizeof(unsigned short), M_NOWAIT); 1105 if (mtag == NULL) 1106 goto bad; 1107 *(unsigned short *)(mtag + 1) = nd_na->nd_na_type; 1108 m_tag_prepend(m, mtag); 1109 } 1110 1111 ip6_output(m, NULL, &ro, 0, &im6o, NULL, NULL); 1112 icmp6_ifstat_inc(ifp, ifs6_out_msg); 1113 icmp6_ifstat_inc(ifp, ifs6_out_neighboradvert); 1114 ICMP6STAT_INC(icp6s_outhist[ND_NEIGHBOR_ADVERT]); 1115 1116 if (ro.ro_rt) { /* we don't cache this route. */ 1117 RTFREE(ro.ro_rt); 1118 } 1119 return; 1120 1121 bad: 1122 if (ro.ro_rt) { 1123 RTFREE(ro.ro_rt); 1124 } 1125 m_freem(m); 1126 return; 1127 } 1128 1129 caddr_t 1130 nd6_ifptomac(struct ifnet *ifp) 1131 { 1132 switch (ifp->if_type) { 1133 case IFT_ARCNET: 1134 case IFT_ETHER: 1135 case IFT_FDDI: 1136 case IFT_IEEE1394: 1137 #ifdef IFT_L2VLAN 1138 case IFT_L2VLAN: 1139 #endif 1140 #ifdef IFT_IEEE80211 1141 case IFT_IEEE80211: 1142 #endif 1143 case IFT_INFINIBAND: 1144 case IFT_BRIDGE: 1145 case IFT_ISO88025: 1146 return IF_LLADDR(ifp); 1147 default: 1148 return NULL; 1149 } 1150 } 1151 1152 struct dadq { 1153 TAILQ_ENTRY(dadq) dad_list; 1154 struct ifaddr *dad_ifa; 1155 int dad_count; /* max NS to send */ 1156 int dad_ns_tcount; /* # of trials to send NS */ 1157 int dad_ns_ocount; /* NS sent so far */ 1158 int dad_ns_icount; 1159 int dad_na_icount; 1160 struct callout dad_timer_ch; 1161 struct vnet *dad_vnet; 1162 }; 1163 1164 static VNET_DEFINE(TAILQ_HEAD(, dadq), dadq); 1165 VNET_DEFINE(int, dad_init) = 0; 1166 #define V_dadq VNET(dadq) 1167 #define V_dad_init VNET(dad_init) 1168 1169 static struct dadq * 1170 nd6_dad_find(struct ifaddr *ifa) 1171 { 1172 struct dadq *dp; 1173 1174 TAILQ_FOREACH(dp, &V_dadq, dad_list) 1175 if (dp->dad_ifa == ifa) 1176 return (dp); 1177 1178 return (NULL); 1179 } 1180 1181 static void 1182 nd6_dad_starttimer(struct dadq *dp, int ticks) 1183 { 1184 1185 callout_reset(&dp->dad_timer_ch, ticks, 1186 (void (*)(void *))nd6_dad_timer, (void *)dp); 1187 } 1188 1189 static void 1190 nd6_dad_stoptimer(struct dadq *dp) 1191 { 1192 1193 callout_stop(&dp->dad_timer_ch); 1194 } 1195 1196 /* 1197 * Start Duplicate Address Detection (DAD) for specified interface address. 1198 */ 1199 void 1200 nd6_dad_start(struct ifaddr *ifa, int delay) 1201 { 1202 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1203 struct dadq *dp; 1204 char ip6buf[INET6_ADDRSTRLEN]; 1205 1206 if (!V_dad_init) { 1207 TAILQ_INIT(&V_dadq); 1208 V_dad_init++; 1209 } 1210 1211 /* 1212 * If we don't need DAD, don't do it. 1213 * There are several cases: 1214 * - DAD is disabled (ip6_dad_count == 0) 1215 * - the interface address is anycast 1216 */ 1217 if (!(ia->ia6_flags & IN6_IFF_TENTATIVE)) { 1218 log(LOG_DEBUG, 1219 "nd6_dad_start: called with non-tentative address " 1220 "%s(%s)\n", 1221 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr), 1222 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1223 return; 1224 } 1225 if (ia->ia6_flags & IN6_IFF_ANYCAST) { 1226 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1227 return; 1228 } 1229 if (!V_ip6_dad_count) { 1230 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1231 return; 1232 } 1233 if (ifa->ifa_ifp == NULL) 1234 panic("nd6_dad_start: ifa->ifa_ifp == NULL"); 1235 if (!(ifa->ifa_ifp->if_flags & IFF_UP)) { 1236 return; 1237 } 1238 if (ND_IFINFO(ifa->ifa_ifp)->flags & ND6_IFF_IFDISABLED) 1239 return; 1240 if (nd6_dad_find(ifa) != NULL) { 1241 /* DAD already in progress */ 1242 return; 1243 } 1244 1245 dp = malloc(sizeof(*dp), M_IP6NDP, M_NOWAIT); 1246 if (dp == NULL) { 1247 log(LOG_ERR, "nd6_dad_start: memory allocation failed for " 1248 "%s(%s)\n", 1249 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr), 1250 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1251 return; 1252 } 1253 bzero(dp, sizeof(*dp)); 1254 callout_init(&dp->dad_timer_ch, 0); 1255 #ifdef VIMAGE 1256 dp->dad_vnet = curvnet; 1257 #endif 1258 TAILQ_INSERT_TAIL(&V_dadq, (struct dadq *)dp, dad_list); 1259 1260 nd6log((LOG_DEBUG, "%s: starting DAD for %s\n", if_name(ifa->ifa_ifp), 1261 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr))); 1262 1263 /* 1264 * Send NS packet for DAD, ip6_dad_count times. 1265 * Note that we must delay the first transmission, if this is the 1266 * first packet to be sent from the interface after interface 1267 * (re)initialization. 1268 */ 1269 dp->dad_ifa = ifa; 1270 ifa_ref(ifa); /* just for safety */ 1271 dp->dad_count = V_ip6_dad_count; 1272 dp->dad_ns_icount = dp->dad_na_icount = 0; 1273 dp->dad_ns_ocount = dp->dad_ns_tcount = 0; 1274 if (delay == 0) { 1275 nd6_dad_ns_output(dp, ifa); 1276 nd6_dad_starttimer(dp, 1277 (long)ND_IFINFO(ifa->ifa_ifp)->retrans * hz / 1000); 1278 } else { 1279 nd6_dad_starttimer(dp, delay); 1280 } 1281 } 1282 1283 /* 1284 * terminate DAD unconditionally. used for address removals. 1285 */ 1286 void 1287 nd6_dad_stop(struct ifaddr *ifa) 1288 { 1289 struct dadq *dp; 1290 1291 if (!V_dad_init) 1292 return; 1293 dp = nd6_dad_find(ifa); 1294 if (!dp) { 1295 /* DAD wasn't started yet */ 1296 return; 1297 } 1298 1299 nd6_dad_stoptimer(dp); 1300 1301 TAILQ_REMOVE(&V_dadq, (struct dadq *)dp, dad_list); 1302 free(dp, M_IP6NDP); 1303 dp = NULL; 1304 ifa_free(ifa); 1305 } 1306 1307 static void 1308 nd6_dad_timer(struct dadq *dp) 1309 { 1310 CURVNET_SET(dp->dad_vnet); 1311 int s; 1312 struct ifaddr *ifa = dp->dad_ifa; 1313 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1314 char ip6buf[INET6_ADDRSTRLEN]; 1315 1316 s = splnet(); /* XXX */ 1317 1318 /* Sanity check */ 1319 if (ia == NULL) { 1320 log(LOG_ERR, "nd6_dad_timer: called with null parameter\n"); 1321 goto done; 1322 } 1323 if (ia->ia6_flags & IN6_IFF_DUPLICATED) { 1324 log(LOG_ERR, "nd6_dad_timer: called with duplicated address " 1325 "%s(%s)\n", 1326 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr), 1327 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1328 goto done; 1329 } 1330 if ((ia->ia6_flags & IN6_IFF_TENTATIVE) == 0) { 1331 log(LOG_ERR, "nd6_dad_timer: called with non-tentative address " 1332 "%s(%s)\n", 1333 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr), 1334 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1335 goto done; 1336 } 1337 1338 /* timeouted with IFF_{RUNNING,UP} check */ 1339 if (dp->dad_ns_tcount > V_dad_maxtry) { 1340 nd6log((LOG_INFO, "%s: could not run DAD, driver problem?\n", 1341 if_name(ifa->ifa_ifp))); 1342 1343 TAILQ_REMOVE(&V_dadq, (struct dadq *)dp, dad_list); 1344 free(dp, M_IP6NDP); 1345 dp = NULL; 1346 ifa_free(ifa); 1347 goto done; 1348 } 1349 1350 /* Need more checks? */ 1351 if (dp->dad_ns_ocount < dp->dad_count) { 1352 /* 1353 * We have more NS to go. Send NS packet for DAD. 1354 */ 1355 nd6_dad_ns_output(dp, ifa); 1356 nd6_dad_starttimer(dp, 1357 (long)ND_IFINFO(ifa->ifa_ifp)->retrans * hz / 1000); 1358 } else { 1359 /* 1360 * We have transmitted sufficient number of DAD packets. 1361 * See what we've got. 1362 */ 1363 int duplicate; 1364 1365 duplicate = 0; 1366 1367 if (dp->dad_na_icount) { 1368 /* 1369 * the check is in nd6_dad_na_input(), 1370 * but just in case 1371 */ 1372 duplicate++; 1373 } 1374 1375 if (dp->dad_ns_icount) { 1376 /* We've seen NS, means DAD has failed. */ 1377 duplicate++; 1378 } 1379 1380 if (duplicate) { 1381 /* (*dp) will be freed in nd6_dad_duplicated() */ 1382 dp = NULL; 1383 nd6_dad_duplicated(ifa); 1384 } else { 1385 /* 1386 * We are done with DAD. No NA came, no NS came. 1387 * No duplicate address found. 1388 */ 1389 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1390 1391 nd6log((LOG_DEBUG, 1392 "%s: DAD complete for %s - no duplicates found\n", 1393 if_name(ifa->ifa_ifp), 1394 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr))); 1395 1396 TAILQ_REMOVE(&V_dadq, (struct dadq *)dp, dad_list); 1397 free(dp, M_IP6NDP); 1398 dp = NULL; 1399 ifa_free(ifa); 1400 } 1401 } 1402 1403 done: 1404 splx(s); 1405 CURVNET_RESTORE(); 1406 } 1407 1408 void 1409 nd6_dad_duplicated(struct ifaddr *ifa) 1410 { 1411 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1412 struct ifnet *ifp; 1413 struct dadq *dp; 1414 char ip6buf[INET6_ADDRSTRLEN]; 1415 1416 dp = nd6_dad_find(ifa); 1417 if (dp == NULL) { 1418 log(LOG_ERR, "nd6_dad_duplicated: DAD structure not found\n"); 1419 return; 1420 } 1421 1422 log(LOG_ERR, "%s: DAD detected duplicate IPv6 address %s: " 1423 "NS in/out=%d/%d, NA in=%d\n", 1424 if_name(ifa->ifa_ifp), ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr), 1425 dp->dad_ns_icount, dp->dad_ns_ocount, dp->dad_na_icount); 1426 1427 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1428 ia->ia6_flags |= IN6_IFF_DUPLICATED; 1429 1430 /* We are done with DAD, with duplicate address found. (failure) */ 1431 nd6_dad_stoptimer(dp); 1432 1433 ifp = ifa->ifa_ifp; 1434 log(LOG_ERR, "%s: DAD complete for %s - duplicate found\n", 1435 if_name(ifp), ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr)); 1436 log(LOG_ERR, "%s: manual intervention required\n", 1437 if_name(ifp)); 1438 1439 /* 1440 * If the address is a link-local address formed from an interface 1441 * identifier based on the hardware address which is supposed to be 1442 * uniquely assigned (e.g., EUI-64 for an Ethernet interface), IP 1443 * operation on the interface SHOULD be disabled. 1444 * [RFC 4862, Section 5.4.5] 1445 */ 1446 if (IN6_IS_ADDR_LINKLOCAL(&ia->ia_addr.sin6_addr)) { 1447 struct in6_addr in6; 1448 1449 /* 1450 * To avoid over-reaction, we only apply this logic when we are 1451 * very sure that hardware addresses are supposed to be unique. 1452 */ 1453 switch (ifp->if_type) { 1454 case IFT_ETHER: 1455 case IFT_FDDI: 1456 case IFT_ATM: 1457 case IFT_IEEE1394: 1458 #ifdef IFT_IEEE80211 1459 case IFT_IEEE80211: 1460 #endif 1461 case IFT_INFINIBAND: 1462 in6 = ia->ia_addr.sin6_addr; 1463 if (in6_get_hw_ifid(ifp, &in6) == 0 && 1464 IN6_ARE_ADDR_EQUAL(&ia->ia_addr.sin6_addr, &in6)) { 1465 ND_IFINFO(ifp)->flags |= ND6_IFF_IFDISABLED; 1466 log(LOG_ERR, "%s: possible hardware address " 1467 "duplication detected, disable IPv6\n", 1468 if_name(ifp)); 1469 } 1470 break; 1471 } 1472 } 1473 1474 TAILQ_REMOVE(&V_dadq, (struct dadq *)dp, dad_list); 1475 free(dp, M_IP6NDP); 1476 dp = NULL; 1477 ifa_free(ifa); 1478 } 1479 1480 static void 1481 nd6_dad_ns_output(struct dadq *dp, struct ifaddr *ifa) 1482 { 1483 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1484 struct ifnet *ifp = ifa->ifa_ifp; 1485 1486 dp->dad_ns_tcount++; 1487 if ((ifp->if_flags & IFF_UP) == 0) { 1488 return; 1489 } 1490 if ((ifp->if_drv_flags & IFF_DRV_RUNNING) == 0) { 1491 return; 1492 } 1493 1494 dp->dad_ns_ocount++; 1495 nd6_ns_output(ifp, NULL, &ia->ia_addr.sin6_addr, NULL, 1); 1496 } 1497 1498 static void 1499 nd6_dad_ns_input(struct ifaddr *ifa) 1500 { 1501 struct in6_ifaddr *ia; 1502 struct ifnet *ifp; 1503 const struct in6_addr *taddr6; 1504 struct dadq *dp; 1505 int duplicate; 1506 1507 if (ifa == NULL) 1508 panic("ifa == NULL in nd6_dad_ns_input"); 1509 1510 ia = (struct in6_ifaddr *)ifa; 1511 ifp = ifa->ifa_ifp; 1512 taddr6 = &ia->ia_addr.sin6_addr; 1513 duplicate = 0; 1514 dp = nd6_dad_find(ifa); 1515 1516 /* Quickhack - completely ignore DAD NS packets */ 1517 if (V_dad_ignore_ns) { 1518 char ip6buf[INET6_ADDRSTRLEN]; 1519 nd6log((LOG_INFO, 1520 "nd6_dad_ns_input: ignoring DAD NS packet for " 1521 "address %s(%s)\n", ip6_sprintf(ip6buf, taddr6), 1522 if_name(ifa->ifa_ifp))); 1523 return; 1524 } 1525 1526 /* 1527 * if I'm yet to start DAD, someone else started using this address 1528 * first. I have a duplicate and you win. 1529 */ 1530 if (dp == NULL || dp->dad_ns_ocount == 0) 1531 duplicate++; 1532 1533 /* XXX more checks for loopback situation - see nd6_dad_timer too */ 1534 1535 if (duplicate) { 1536 dp = NULL; /* will be freed in nd6_dad_duplicated() */ 1537 nd6_dad_duplicated(ifa); 1538 } else { 1539 /* 1540 * not sure if I got a duplicate. 1541 * increment ns count and see what happens. 1542 */ 1543 if (dp) 1544 dp->dad_ns_icount++; 1545 } 1546 } 1547 1548 static void 1549 nd6_dad_na_input(struct ifaddr *ifa) 1550 { 1551 struct dadq *dp; 1552 1553 if (ifa == NULL) 1554 panic("ifa == NULL in nd6_dad_na_input"); 1555 1556 dp = nd6_dad_find(ifa); 1557 if (dp) 1558 dp->dad_na_icount++; 1559 1560 /* remove the address. */ 1561 nd6_dad_duplicated(ifa); 1562 } 1563