nd6_nbr.c revision 185571
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: head/sys/netinet6/nd6_nbr.c 185571 2008-12-02 21:37:28Z bz $"); 34 35#include "opt_inet.h" 36#include "opt_inet6.h" 37#include "opt_ipsec.h" 38#include "opt_carp.h" 39#include "opt_mpath.h" 40 41#include <sys/param.h> 42#include <sys/systm.h> 43#include <sys/malloc.h> 44#include <sys/mbuf.h> 45#include <sys/socket.h> 46#include <sys/sockio.h> 47#include <sys/time.h> 48#include <sys/kernel.h> 49#include <sys/errno.h> 50#include <sys/syslog.h> 51#include <sys/queue.h> 52#include <sys/callout.h> 53#include <sys/vimage.h> 54 55#include <net/if.h> 56#include <net/if_types.h> 57#include <net/if_dl.h> 58#include <net/if_var.h> 59#include <net/route.h> 60#ifdef RADIX_MPATH 61#include <net/radix_mpath.h> 62#endif 63 64#include <netinet/in.h> 65#include <netinet/in_var.h> 66#include <netinet6/in6_var.h> 67#include <netinet6/in6_ifattach.h> 68#include <netinet/ip6.h> 69#include <netinet6/ip6_var.h> 70#include <netinet6/scope6_var.h> 71#include <netinet6/nd6.h> 72#include <netinet/icmp6.h> 73#include <netinet6/vinet6.h> 74 75#ifdef DEV_CARP 76#include <netinet/ip_carp.h> 77#endif 78 79#define SDL(s) ((struct sockaddr_dl *)s) 80 81struct dadq; 82static struct dadq *nd6_dad_find(struct ifaddr *); 83static void nd6_dad_starttimer(struct dadq *, int); 84static void nd6_dad_stoptimer(struct dadq *); 85static void nd6_dad_timer(struct ifaddr *); 86static void nd6_dad_ns_output(struct dadq *, struct ifaddr *); 87static void nd6_dad_ns_input(struct ifaddr *); 88static void nd6_dad_na_input(struct ifaddr *); 89 90#ifdef VIMAGE_GLOBALS 91int dad_ignore_ns; 92int dad_maxtry; 93#endif 94 95/* 96 * Input a Neighbor Solicitation Message. 97 * 98 * Based on RFC 2461 99 * Based on RFC 2462 (duplicate address detection) 100 */ 101void 102nd6_ns_input(struct mbuf *m, int off, int icmp6len) 103{ 104 INIT_VNET_INET6(curvnet); 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 union nd_opts ndopts; 118 struct sockaddr_dl *proxydl = NULL; 119 char ip6bufs[INET6_ADDRSTRLEN], ip6bufd[INET6_ADDRSTRLEN]; 120 121#ifndef PULLDOWN_TEST 122 IP6_EXTHDR_CHECK(m, off, icmp6len,); 123 nd_ns = (struct nd_neighbor_solicit *)((caddr_t)ip6 + off); 124#else 125 IP6_EXTHDR_GET(nd_ns, struct nd_neighbor_solicit *, m, off, icmp6len); 126 if (nd_ns == NULL) { 127 V_icmp6stat.icp6s_tooshort++; 128 return; 129 } 130#endif 131 ip6 = mtod(m, struct ip6_hdr *); /* adjust pointer for safety */ 132 taddr6 = nd_ns->nd_ns_target; 133 if (in6_setscope(&taddr6, ifp, NULL) != 0) 134 goto bad; 135 136 if (ip6->ip6_hlim != 255) { 137 nd6log((LOG_ERR, 138 "nd6_ns_input: invalid hlim (%d) from %s to %s on %s\n", 139 ip6->ip6_hlim, ip6_sprintf(ip6bufs, &ip6->ip6_src), 140 ip6_sprintf(ip6bufd, &ip6->ip6_dst), if_name(ifp))); 141 goto bad; 142 } 143 144 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) { 145 /* dst has to be a solicited node multicast address. */ 146 if (daddr6.s6_addr16[0] == IPV6_ADDR_INT16_MLL && 147 /* don't check ifindex portion */ 148 daddr6.s6_addr32[1] == 0 && 149 daddr6.s6_addr32[2] == IPV6_ADDR_INT32_ONE && 150 daddr6.s6_addr8[12] == 0xff) { 151 ; /* good */ 152 } else { 153 nd6log((LOG_INFO, "nd6_ns_input: bad DAD packet " 154 "(wrong ip6 dst)\n")); 155 goto bad; 156 } 157 } else if (!V_nd6_onlink_ns_rfc4861) { 158 struct sockaddr_in6 src_sa6; 159 160 /* 161 * According to recent IETF discussions, it is not a good idea 162 * to accept a NS from an address which would not be deemed 163 * to be a neighbor otherwise. This point is expected to be 164 * clarified in future revisions of the specification. 165 */ 166 bzero(&src_sa6, sizeof(src_sa6)); 167 src_sa6.sin6_family = AF_INET6; 168 src_sa6.sin6_len = sizeof(src_sa6); 169 src_sa6.sin6_addr = saddr6; 170 if (!nd6_is_addr_neighbor(&src_sa6, ifp)) { 171 nd6log((LOG_INFO, "nd6_ns_input: " 172 "NS packet from non-neighbor\n")); 173 goto bad; 174 } 175 } 176 177 if (IN6_IS_ADDR_MULTICAST(&taddr6)) { 178 nd6log((LOG_INFO, "nd6_ns_input: bad NS target (multicast)\n")); 179 goto bad; 180 } 181 182 icmp6len -= sizeof(*nd_ns); 183 nd6_option_init(nd_ns + 1, icmp6len, &ndopts); 184 if (nd6_options(&ndopts) < 0) { 185 nd6log((LOG_INFO, 186 "nd6_ns_input: invalid ND option, ignored\n")); 187 /* nd6_options have incremented stats */ 188 goto freeit; 189 } 190 191 if (ndopts.nd_opts_src_lladdr) { 192 lladdr = (char *)(ndopts.nd_opts_src_lladdr + 1); 193 lladdrlen = ndopts.nd_opts_src_lladdr->nd_opt_len << 3; 194 } 195 196 if (IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_src) && lladdr) { 197 nd6log((LOG_INFO, "nd6_ns_input: bad DAD packet " 198 "(link-layer address option)\n")); 199 goto bad; 200 } 201 202 /* 203 * Attaching target link-layer address to the NA? 204 * (RFC 2461 7.2.4) 205 * 206 * NS IP dst is unicast/anycast MUST NOT add 207 * NS IP dst is solicited-node multicast MUST add 208 * 209 * In implementation, we add target link-layer address by default. 210 * We do not add one in MUST NOT cases. 211 */ 212 if (!IN6_IS_ADDR_MULTICAST(&daddr6)) 213 tlladdr = 0; 214 else 215 tlladdr = 1; 216 217 /* 218 * Target address (taddr6) must be either: 219 * (1) Valid unicast/anycast address for my receiving interface, 220 * (2) Unicast address for which I'm offering proxy service, or 221 * (3) "tentative" address on which DAD is being performed. 222 */ 223 /* (1) and (3) check. */ 224#ifdef DEV_CARP 225 if (ifp->if_carp) 226 ifa = carp_iamatch6(ifp->if_carp, &taddr6); 227 if (ifa == NULL) 228 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &taddr6); 229#else 230 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &taddr6); 231#endif 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#ifdef RADIX_MPATH 248 bzero(&ro, sizeof(ro)); 249 ro.ro_dst = tsin6; 250 rtalloc_mpath((struct route *)&ro, RTF_ANNOUNCE); 251 rt = ro.ro_rt; 252#else 253 rt = rtalloc1((struct sockaddr *)&tsin6, 0, 0); 254#endif 255 need_proxy = (rt && (rt->rt_flags & RTF_ANNOUNCE) != 0 && 256 rt->rt_gateway->sa_family == AF_LINK); 257 if (rt) 258 rtfree(rt); 259 if (need_proxy) { 260 /* 261 * proxy NDP for single entry 262 */ 263 ifa = (struct ifaddr *)in6ifa_ifpforlinklocal(ifp, 264 IN6_IFF_NOTREADY|IN6_IFF_ANYCAST); 265 if (ifa) { 266 proxy = 1; 267 proxydl = SDL(rt->rt_gateway); 268 } 269 } 270 } 271 if (ifa == NULL) { 272 /* 273 * We've got an NS packet, and we don't have that adddress 274 * assigned for us. We MUST silently ignore it. 275 * See RFC2461 7.2.3. 276 */ 277 goto freeit; 278 } 279 myaddr6 = *IFA_IN6(ifa); 280 anycast = ((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_ANYCAST; 281 tentative = ((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_TENTATIVE; 282 if (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_DUPLICATED) 283 goto freeit; 284 285 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) { 286 nd6log((LOG_INFO, "nd6_ns_input: lladdrlen mismatch for %s " 287 "(if %d, NS packet %d)\n", 288 ip6_sprintf(ip6bufs, &taddr6), 289 ifp->if_addrlen, lladdrlen - 2)); 290 goto bad; 291 } 292 293 if (IN6_ARE_ADDR_EQUAL(&myaddr6, &saddr6)) { 294 nd6log((LOG_INFO, "nd6_ns_input: duplicate IP6 address %s\n", 295 ip6_sprintf(ip6bufs, &saddr6))); 296 goto freeit; 297 } 298 299 /* 300 * We have neighbor solicitation packet, with target address equals to 301 * one of my tentative address. 302 * 303 * src addr how to process? 304 * --- --- 305 * multicast of course, invalid (rejected in ip6_input) 306 * unicast somebody is doing address resolution -> ignore 307 * unspec dup address detection 308 * 309 * The processing is defined in RFC 2462. 310 */ 311 if (tentative) { 312 /* 313 * If source address is unspecified address, it is for 314 * duplicate address detection. 315 * 316 * If not, the packet is for addess resolution; 317 * silently ignore it. 318 */ 319 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) 320 nd6_dad_ns_input(ifa); 321 322 goto freeit; 323 } 324 325 /* 326 * If the source address is unspecified address, entries must not 327 * be created or updated. 328 * It looks that sender is performing DAD. Output NA toward 329 * all-node multicast address, to tell the sender that I'm using 330 * the address. 331 * S bit ("solicited") must be zero. 332 */ 333 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) { 334 struct in6_addr in6_all; 335 336 in6_all = in6addr_linklocal_allnodes; 337 if (in6_setscope(&in6_all, ifp, NULL) != 0) 338 goto bad; 339 nd6_na_output(ifp, &in6_all, &taddr6, 340 ((anycast || proxy || !tlladdr) ? 0 : ND_NA_FLAG_OVERRIDE) | 341 (V_ip6_forwarding ? ND_NA_FLAG_ROUTER : 0), 342 tlladdr, (struct sockaddr *)proxydl); 343 goto freeit; 344 } 345 346 nd6_cache_lladdr(ifp, &saddr6, lladdr, lladdrlen, 347 ND_NEIGHBOR_SOLICIT, 0); 348 349 nd6_na_output(ifp, &saddr6, &taddr6, 350 ((anycast || proxy || !tlladdr) ? 0 : ND_NA_FLAG_OVERRIDE) | 351 (V_ip6_forwarding ? ND_NA_FLAG_ROUTER : 0) | ND_NA_FLAG_SOLICITED, 352 tlladdr, (struct sockaddr *)proxydl); 353 freeit: 354 m_freem(m); 355 return; 356 357 bad: 358 nd6log((LOG_ERR, "nd6_ns_input: src=%s\n", 359 ip6_sprintf(ip6bufs, &saddr6))); 360 nd6log((LOG_ERR, "nd6_ns_input: dst=%s\n", 361 ip6_sprintf(ip6bufs, &daddr6))); 362 nd6log((LOG_ERR, "nd6_ns_input: tgt=%s\n", 363 ip6_sprintf(ip6bufs, &taddr6))); 364 V_icmp6stat.icp6s_badns++; 365 m_freem(m); 366} 367 368/* 369 * Output a Neighbor Solicitation Message. Caller specifies: 370 * - ICMP6 header source IP6 address 371 * - ND6 header target IP6 address 372 * - ND6 header source datalink address 373 * 374 * Based on RFC 2461 375 * Based on RFC 2462 (duplicate address detection) 376 * 377 * ln - for source address determination 378 * dad - duplicate address detection 379 */ 380void 381nd6_ns_output(struct ifnet *ifp, const struct in6_addr *daddr6, 382 const struct in6_addr *taddr6, struct llinfo_nd6 *ln, int dad) 383{ 384 INIT_VNET_INET6(ifp->if_vnet); 385 struct mbuf *m; 386 struct ip6_hdr *ip6; 387 struct nd_neighbor_solicit *nd_ns; 388 struct in6_addr *src, src_in; 389 struct ip6_moptions im6o; 390 int icmp6len; 391 int maxlen; 392 caddr_t mac; 393 struct route_in6 ro; 394 395 bzero(&ro, sizeof(ro)); 396 397 if (IN6_IS_ADDR_MULTICAST(taddr6)) 398 return; 399 400 /* estimate the size of message */ 401 maxlen = sizeof(*ip6) + sizeof(*nd_ns); 402 maxlen += (sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7; 403 if (max_linkhdr + maxlen >= MCLBYTES) { 404#ifdef DIAGNOSTIC 405 printf("nd6_ns_output: max_linkhdr + maxlen >= MCLBYTES " 406 "(%d + %d > %d)\n", max_linkhdr, maxlen, MCLBYTES); 407#endif 408 return; 409 } 410 411 MGETHDR(m, M_DONTWAIT, MT_DATA); 412 if (m && max_linkhdr + maxlen >= MHLEN) { 413 MCLGET(m, M_DONTWAIT); 414 if ((m->m_flags & M_EXT) == 0) { 415 m_free(m); 416 m = NULL; 417 } 418 } 419 if (m == NULL) 420 return; 421 m->m_pkthdr.rcvif = NULL; 422 423 if (daddr6 == NULL || IN6_IS_ADDR_MULTICAST(daddr6)) { 424 m->m_flags |= M_MCAST; 425 im6o.im6o_multicast_ifp = ifp; 426 im6o.im6o_multicast_hlim = 255; 427 im6o.im6o_multicast_loop = 0; 428 } 429 430 icmp6len = sizeof(*nd_ns); 431 m->m_pkthdr.len = m->m_len = sizeof(*ip6) + icmp6len; 432 m->m_data += max_linkhdr; /* or MH_ALIGN() equivalent? */ 433 434 /* fill neighbor solicitation packet */ 435 ip6 = mtod(m, struct ip6_hdr *); 436 ip6->ip6_flow = 0; 437 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 438 ip6->ip6_vfc |= IPV6_VERSION; 439 /* ip6->ip6_plen will be set later */ 440 ip6->ip6_nxt = IPPROTO_ICMPV6; 441 ip6->ip6_hlim = 255; 442 if (daddr6) 443 ip6->ip6_dst = *daddr6; 444 else { 445 ip6->ip6_dst.s6_addr16[0] = IPV6_ADDR_INT16_MLL; 446 ip6->ip6_dst.s6_addr16[1] = 0; 447 ip6->ip6_dst.s6_addr32[1] = 0; 448 ip6->ip6_dst.s6_addr32[2] = IPV6_ADDR_INT32_ONE; 449 ip6->ip6_dst.s6_addr32[3] = taddr6->s6_addr32[3]; 450 ip6->ip6_dst.s6_addr8[12] = 0xff; 451 if (in6_setscope(&ip6->ip6_dst, ifp, NULL) != 0) 452 goto bad; 453 } 454 if (!dad) { 455 /* 456 * RFC2461 7.2.2: 457 * "If the source address of the packet prompting the 458 * solicitation is the same as one of the addresses assigned 459 * to the outgoing interface, that address SHOULD be placed 460 * in the IP Source Address of the outgoing solicitation. 461 * Otherwise, any one of the addresses assigned to the 462 * interface should be used." 463 * 464 * We use the source address for the prompting packet 465 * (saddr6), if: 466 * - saddr6 is given from the caller (by giving "ln"), and 467 * - saddr6 belongs to the outgoing interface. 468 * Otherwise, we perform the source address selection as usual. 469 */ 470 struct ip6_hdr *hip6; /* hold ip6 */ 471 struct in6_addr *hsrc = NULL; 472 473 if (ln && ln->ln_hold) { 474 /* 475 * assuming every packet in ln_hold has the same IP 476 * header 477 */ 478 hip6 = mtod(ln->ln_hold, struct ip6_hdr *); 479 /* XXX pullup? */ 480 if (sizeof(*hip6) < ln->ln_hold->m_len) 481 hsrc = &hip6->ip6_src; 482 else 483 hsrc = NULL; 484 } 485 if (hsrc && in6ifa_ifpwithaddr(ifp, hsrc)) 486 src = hsrc; 487 else { 488 int error; 489 struct sockaddr_in6 dst_sa; 490 491 bzero(&dst_sa, sizeof(dst_sa)); 492 dst_sa.sin6_family = AF_INET6; 493 dst_sa.sin6_len = sizeof(dst_sa); 494 dst_sa.sin6_addr = ip6->ip6_dst; 495 496 src = in6_selectsrc(&dst_sa, NULL, 497 NULL, &ro, NULL, NULL, &error); 498 if (src == NULL) { 499 char ip6buf[INET6_ADDRSTRLEN]; 500 nd6log((LOG_DEBUG, 501 "nd6_ns_output: source can't be " 502 "determined: dst=%s, error=%d\n", 503 ip6_sprintf(ip6buf, &dst_sa.sin6_addr), 504 error)); 505 goto bad; 506 } 507 } 508 } else { 509 /* 510 * Source address for DAD packet must always be IPv6 511 * unspecified address. (0::0) 512 * We actually don't have to 0-clear the address (we did it 513 * above), but we do so here explicitly to make the intention 514 * clearer. 515 */ 516 bzero(&src_in, sizeof(src_in)); 517 src = &src_in; 518 } 519 ip6->ip6_src = *src; 520 nd_ns = (struct nd_neighbor_solicit *)(ip6 + 1); 521 nd_ns->nd_ns_type = ND_NEIGHBOR_SOLICIT; 522 nd_ns->nd_ns_code = 0; 523 nd_ns->nd_ns_reserved = 0; 524 nd_ns->nd_ns_target = *taddr6; 525 in6_clearscope(&nd_ns->nd_ns_target); /* XXX */ 526 527 /* 528 * Add source link-layer address option. 529 * 530 * spec implementation 531 * --- --- 532 * DAD packet MUST NOT do not add the option 533 * there's no link layer address: 534 * impossible do not add the option 535 * there's link layer address: 536 * Multicast NS MUST add one add the option 537 * Unicast NS SHOULD add one add the option 538 */ 539 if (!dad && (mac = nd6_ifptomac(ifp))) { 540 int optlen = sizeof(struct nd_opt_hdr) + ifp->if_addrlen; 541 struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)(nd_ns + 1); 542 /* 8 byte alignments... */ 543 optlen = (optlen + 7) & ~7; 544 545 m->m_pkthdr.len += optlen; 546 m->m_len += optlen; 547 icmp6len += optlen; 548 bzero((caddr_t)nd_opt, optlen); 549 nd_opt->nd_opt_type = ND_OPT_SOURCE_LINKADDR; 550 nd_opt->nd_opt_len = optlen >> 3; 551 bcopy(mac, (caddr_t)(nd_opt + 1), ifp->if_addrlen); 552 } 553 554 ip6->ip6_plen = htons((u_short)icmp6len); 555 nd_ns->nd_ns_cksum = 0; 556 nd_ns->nd_ns_cksum = 557 in6_cksum(m, IPPROTO_ICMPV6, sizeof(*ip6), icmp6len); 558 559 ip6_output(m, NULL, &ro, dad ? IPV6_UNSPECSRC : 0, &im6o, NULL, NULL); 560 icmp6_ifstat_inc(ifp, ifs6_out_msg); 561 icmp6_ifstat_inc(ifp, ifs6_out_neighborsolicit); 562 V_icmp6stat.icp6s_outhist[ND_NEIGHBOR_SOLICIT]++; 563 564 if (ro.ro_rt) { /* we don't cache this route. */ 565 RTFREE(ro.ro_rt); 566 } 567 return; 568 569 bad: 570 if (ro.ro_rt) { 571 RTFREE(ro.ro_rt); 572 } 573 m_freem(m); 574 return; 575} 576 577/* 578 * Neighbor advertisement input handling. 579 * 580 * Based on RFC 2461 581 * Based on RFC 2462 (duplicate address detection) 582 * 583 * the following items are not implemented yet: 584 * - proxy advertisement delay rule (RFC2461 7.2.8, last paragraph, SHOULD) 585 * - anycast advertisement delay rule (RFC2461 7.2.7, SHOULD) 586 */ 587void 588nd6_na_input(struct mbuf *m, int off, int icmp6len) 589{ 590 INIT_VNET_INET6(curvnet); 591 struct ifnet *ifp = m->m_pkthdr.rcvif; 592 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 593 struct nd_neighbor_advert *nd_na; 594 struct in6_addr daddr6 = ip6->ip6_dst; 595 struct in6_addr taddr6; 596 int flags; 597 int is_router; 598 int is_solicited; 599 int is_override; 600 char *lladdr = NULL; 601 int lladdrlen = 0; 602 struct ifaddr *ifa; 603 struct llinfo_nd6 *ln; 604 struct rtentry *rt; 605 struct sockaddr_dl *sdl; 606 union nd_opts ndopts; 607 char ip6bufs[INET6_ADDRSTRLEN], ip6bufd[INET6_ADDRSTRLEN]; 608 609 if (ip6->ip6_hlim != 255) { 610 nd6log((LOG_ERR, 611 "nd6_na_input: invalid hlim (%d) from %s to %s on %s\n", 612 ip6->ip6_hlim, ip6_sprintf(ip6bufs, &ip6->ip6_src), 613 ip6_sprintf(ip6bufd, &ip6->ip6_dst), if_name(ifp))); 614 goto bad; 615 } 616 617#ifndef PULLDOWN_TEST 618 IP6_EXTHDR_CHECK(m, off, icmp6len,); 619 nd_na = (struct nd_neighbor_advert *)((caddr_t)ip6 + off); 620#else 621 IP6_EXTHDR_GET(nd_na, struct nd_neighbor_advert *, m, off, icmp6len); 622 if (nd_na == NULL) { 623 V_icmp6stat.icp6s_tooshort++; 624 return; 625 } 626#endif 627 628 flags = nd_na->nd_na_flags_reserved; 629 is_router = ((flags & ND_NA_FLAG_ROUTER) != 0); 630 is_solicited = ((flags & ND_NA_FLAG_SOLICITED) != 0); 631 is_override = ((flags & ND_NA_FLAG_OVERRIDE) != 0); 632 633 taddr6 = nd_na->nd_na_target; 634 if (in6_setscope(&taddr6, ifp, NULL)) 635 goto bad; /* XXX: impossible */ 636 637 if (IN6_IS_ADDR_MULTICAST(&taddr6)) { 638 nd6log((LOG_ERR, 639 "nd6_na_input: invalid target address %s\n", 640 ip6_sprintf(ip6bufs, &taddr6))); 641 goto bad; 642 } 643 if (IN6_IS_ADDR_MULTICAST(&daddr6)) 644 if (is_solicited) { 645 nd6log((LOG_ERR, 646 "nd6_na_input: a solicited adv is multicasted\n")); 647 goto bad; 648 } 649 650 icmp6len -= sizeof(*nd_na); 651 nd6_option_init(nd_na + 1, icmp6len, &ndopts); 652 if (nd6_options(&ndopts) < 0) { 653 nd6log((LOG_INFO, 654 "nd6_na_input: invalid ND option, ignored\n")); 655 /* nd6_options have incremented stats */ 656 goto freeit; 657 } 658 659 if (ndopts.nd_opts_tgt_lladdr) { 660 lladdr = (char *)(ndopts.nd_opts_tgt_lladdr + 1); 661 lladdrlen = ndopts.nd_opts_tgt_lladdr->nd_opt_len << 3; 662 } 663 664 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &taddr6); 665 666 /* 667 * Target address matches one of my interface address. 668 * 669 * If my address is tentative, this means that there's somebody 670 * already using the same address as mine. This indicates DAD failure. 671 * This is defined in RFC 2462. 672 * 673 * Otherwise, process as defined in RFC 2461. 674 */ 675 if (ifa 676 && (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_TENTATIVE)) { 677 nd6_dad_na_input(ifa); 678 goto freeit; 679 } 680 681 /* Just for safety, maybe unnecessary. */ 682 if (ifa) { 683 log(LOG_ERR, 684 "nd6_na_input: duplicate IP6 address %s\n", 685 ip6_sprintf(ip6bufs, &taddr6)); 686 goto freeit; 687 } 688 689 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) { 690 nd6log((LOG_INFO, "nd6_na_input: lladdrlen mismatch for %s " 691 "(if %d, NA packet %d)\n", ip6_sprintf(ip6bufs, &taddr6), 692 ifp->if_addrlen, lladdrlen - 2)); 693 goto bad; 694 } 695 696 /* 697 * If no neighbor cache entry is found, NA SHOULD silently be 698 * discarded. 699 */ 700 rt = nd6_lookup(&taddr6, 0, ifp); 701 if ((rt == NULL) || 702 ((ln = (struct llinfo_nd6 *)rt->rt_llinfo) == NULL) || 703 ((sdl = SDL(rt->rt_gateway)) == NULL)) 704 goto freeit; 705 706 if (ln->ln_state == ND6_LLINFO_INCOMPLETE) { 707 /* 708 * If the link-layer has address, and no lladdr option came, 709 * discard the packet. 710 */ 711 if (ifp->if_addrlen && lladdr == NULL) 712 goto freeit; 713 714 /* 715 * Record link-layer address, and update the state. 716 */ 717 sdl->sdl_alen = ifp->if_addrlen; 718 bcopy(lladdr, LLADDR(sdl), ifp->if_addrlen); 719 if (is_solicited) { 720 ln->ln_state = ND6_LLINFO_REACHABLE; 721 ln->ln_byhint = 0; 722 if (!ND6_LLINFO_PERMANENT(ln)) { 723 nd6_llinfo_settimer(ln, 724 (long)ND_IFINFO(rt->rt_ifp)->reachable * hz); 725 } 726 } else { 727 ln->ln_state = ND6_LLINFO_STALE; 728 nd6_llinfo_settimer(ln, (long)V_nd6_gctimer * hz); 729 } 730 if ((ln->ln_router = is_router) != 0) { 731 /* 732 * This means a router's state has changed from 733 * non-reachable to probably reachable, and might 734 * affect the status of associated prefixes.. 735 */ 736 pfxlist_onlink_check(); 737 } 738 } else { 739 int llchange; 740 741 /* 742 * Check if the link-layer address has changed or not. 743 */ 744 if (lladdr == NULL) 745 llchange = 0; 746 else { 747 if (sdl->sdl_alen) { 748 if (bcmp(lladdr, LLADDR(sdl), ifp->if_addrlen)) 749 llchange = 1; 750 else 751 llchange = 0; 752 } else 753 llchange = 1; 754 } 755 756 /* 757 * This is VERY complex. Look at it with care. 758 * 759 * override solicit lladdr llchange action 760 * (L: record lladdr) 761 * 762 * 0 0 n -- (2c) 763 * 0 0 y n (2b) L 764 * 0 0 y y (1) REACHABLE->STALE 765 * 0 1 n -- (2c) *->REACHABLE 766 * 0 1 y n (2b) L *->REACHABLE 767 * 0 1 y y (1) REACHABLE->STALE 768 * 1 0 n -- (2a) 769 * 1 0 y n (2a) L 770 * 1 0 y y (2a) L *->STALE 771 * 1 1 n -- (2a) *->REACHABLE 772 * 1 1 y n (2a) L *->REACHABLE 773 * 1 1 y y (2a) L *->REACHABLE 774 */ 775 if (!is_override && (lladdr != NULL && llchange)) { /* (1) */ 776 /* 777 * If state is REACHABLE, make it STALE. 778 * no other updates should be done. 779 */ 780 if (ln->ln_state == ND6_LLINFO_REACHABLE) { 781 ln->ln_state = ND6_LLINFO_STALE; 782 nd6_llinfo_settimer(ln, (long)V_nd6_gctimer * hz); 783 } 784 goto freeit; 785 } else if (is_override /* (2a) */ 786 || (!is_override && (lladdr != NULL && !llchange)) /* (2b) */ 787 || lladdr == NULL) { /* (2c) */ 788 /* 789 * Update link-local address, if any. 790 */ 791 if (lladdr != NULL) { 792 sdl->sdl_alen = ifp->if_addrlen; 793 bcopy(lladdr, LLADDR(sdl), ifp->if_addrlen); 794 } 795 796 /* 797 * If solicited, make the state REACHABLE. 798 * If not solicited and the link-layer address was 799 * changed, make it STALE. 800 */ 801 if (is_solicited) { 802 ln->ln_state = ND6_LLINFO_REACHABLE; 803 ln->ln_byhint = 0; 804 if (!ND6_LLINFO_PERMANENT(ln)) { 805 nd6_llinfo_settimer(ln, 806 (long)ND_IFINFO(ifp)->reachable * hz); 807 } 808 } else { 809 if (lladdr != NULL && llchange) { 810 ln->ln_state = ND6_LLINFO_STALE; 811 nd6_llinfo_settimer(ln, 812 (long)V_nd6_gctimer * hz); 813 } 814 } 815 } 816 817 if (ln->ln_router && !is_router) { 818 /* 819 * The peer dropped the router flag. 820 * Remove the sender from the Default Router List and 821 * update the Destination Cache entries. 822 */ 823 struct nd_defrouter *dr; 824 struct in6_addr *in6; 825 int s; 826 827 in6 = &((struct sockaddr_in6 *)rt_key(rt))->sin6_addr; 828 829 /* 830 * Lock to protect the default router list. 831 * XXX: this might be unnecessary, since this function 832 * is only called under the network software interrupt 833 * context. However, we keep it just for safety. 834 */ 835 s = splnet(); 836 dr = defrouter_lookup(in6, ifp); 837 if (dr) 838 defrtrlist_del(dr); 839 else if (!V_ip6_forwarding) { 840 /* 841 * Even if the neighbor is not in the default 842 * router list, the neighbor may be used 843 * as a next hop for some destinations 844 * (e.g. redirect case). So we must 845 * call rt6_flush explicitly. 846 */ 847 rt6_flush(&ip6->ip6_src, ifp); 848 } 849 splx(s); 850 } 851 ln->ln_router = is_router; 852 } 853 rt->rt_flags &= ~RTF_REJECT; 854 ln->ln_asked = 0; 855 if (ln->ln_hold) { 856 struct mbuf *m_hold, *m_hold_next; 857 858 /* 859 * reset the ln_hold in advance, to explicitly 860 * prevent a ln_hold lookup in nd6_output() 861 * (wouldn't happen, though...) 862 */ 863 for (m_hold = ln->ln_hold; 864 m_hold; m_hold = m_hold_next) { 865 m_hold_next = m_hold->m_nextpkt; 866 m_hold->m_nextpkt = NULL; 867 /* 868 * we assume ifp is not a loopback here, so just set 869 * the 2nd argument as the 1st one. 870 */ 871 nd6_output(ifp, ifp, m_hold, 872 (struct sockaddr_in6 *)rt_key(rt), rt); 873 } 874 ln->ln_hold = NULL; 875 } 876 877 freeit: 878 m_freem(m); 879 return; 880 881 bad: 882 V_icmp6stat.icp6s_badna++; 883 m_freem(m); 884} 885 886/* 887 * Neighbor advertisement output handling. 888 * 889 * Based on RFC 2461 890 * 891 * the following items are not implemented yet: 892 * - proxy advertisement delay rule (RFC2461 7.2.8, last paragraph, SHOULD) 893 * - anycast advertisement delay rule (RFC2461 7.2.7, SHOULD) 894 * 895 * tlladdr - 1 if include target link-layer address 896 * sdl0 - sockaddr_dl (= proxy NA) or NULL 897 */ 898void 899nd6_na_output(struct ifnet *ifp, const struct in6_addr *daddr6_0, 900 const struct in6_addr *taddr6, u_long flags, int tlladdr, 901 struct sockaddr *sdl0) 902{ 903 INIT_VNET_INET6(ifp->if_vnet); 904 struct mbuf *m; 905 struct ip6_hdr *ip6; 906 struct nd_neighbor_advert *nd_na; 907 struct ip6_moptions im6o; 908 struct in6_addr *src, daddr6; 909 struct sockaddr_in6 dst_sa; 910 int icmp6len, maxlen, error; 911 caddr_t mac = NULL; 912 struct route_in6 ro; 913 914 bzero(&ro, sizeof(ro)); 915 916 daddr6 = *daddr6_0; /* make a local copy for modification */ 917 918 /* estimate the size of message */ 919 maxlen = sizeof(*ip6) + sizeof(*nd_na); 920 maxlen += (sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7; 921 if (max_linkhdr + maxlen >= MCLBYTES) { 922#ifdef DIAGNOSTIC 923 printf("nd6_na_output: max_linkhdr + maxlen >= MCLBYTES " 924 "(%d + %d > %d)\n", max_linkhdr, maxlen, MCLBYTES); 925#endif 926 return; 927 } 928 929 MGETHDR(m, M_DONTWAIT, MT_DATA); 930 if (m && max_linkhdr + maxlen >= MHLEN) { 931 MCLGET(m, M_DONTWAIT); 932 if ((m->m_flags & M_EXT) == 0) { 933 m_free(m); 934 m = NULL; 935 } 936 } 937 if (m == NULL) 938 return; 939 m->m_pkthdr.rcvif = NULL; 940 941 if (IN6_IS_ADDR_MULTICAST(&daddr6)) { 942 m->m_flags |= M_MCAST; 943 im6o.im6o_multicast_ifp = ifp; 944 im6o.im6o_multicast_hlim = 255; 945 im6o.im6o_multicast_loop = 0; 946 } 947 948 icmp6len = sizeof(*nd_na); 949 m->m_pkthdr.len = m->m_len = sizeof(struct ip6_hdr) + icmp6len; 950 m->m_data += max_linkhdr; /* or MH_ALIGN() equivalent? */ 951 952 /* fill neighbor advertisement packet */ 953 ip6 = mtod(m, struct ip6_hdr *); 954 ip6->ip6_flow = 0; 955 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 956 ip6->ip6_vfc |= IPV6_VERSION; 957 ip6->ip6_nxt = IPPROTO_ICMPV6; 958 ip6->ip6_hlim = 255; 959 if (IN6_IS_ADDR_UNSPECIFIED(&daddr6)) { 960 /* reply to DAD */ 961 daddr6.s6_addr16[0] = IPV6_ADDR_INT16_MLL; 962 daddr6.s6_addr16[1] = 0; 963 daddr6.s6_addr32[1] = 0; 964 daddr6.s6_addr32[2] = 0; 965 daddr6.s6_addr32[3] = IPV6_ADDR_INT32_ONE; 966 if (in6_setscope(&daddr6, ifp, NULL)) 967 goto bad; 968 969 flags &= ~ND_NA_FLAG_SOLICITED; 970 } 971 ip6->ip6_dst = daddr6; 972 bzero(&dst_sa, sizeof(struct sockaddr_in6)); 973 dst_sa.sin6_family = AF_INET6; 974 dst_sa.sin6_len = sizeof(struct sockaddr_in6); 975 dst_sa.sin6_addr = daddr6; 976 977 /* 978 * Select a source whose scope is the same as that of the dest. 979 */ 980 bcopy(&dst_sa, &ro.ro_dst, sizeof(dst_sa)); 981 src = in6_selectsrc(&dst_sa, NULL, NULL, &ro, NULL, NULL, &error); 982 if (src == NULL) { 983 char ip6buf[INET6_ADDRSTRLEN]; 984 nd6log((LOG_DEBUG, "nd6_na_output: source can't be " 985 "determined: dst=%s, error=%d\n", 986 ip6_sprintf(ip6buf, &dst_sa.sin6_addr), error)); 987 goto bad; 988 } 989 ip6->ip6_src = *src; 990 nd_na = (struct nd_neighbor_advert *)(ip6 + 1); 991 nd_na->nd_na_type = ND_NEIGHBOR_ADVERT; 992 nd_na->nd_na_code = 0; 993 nd_na->nd_na_target = *taddr6; 994 in6_clearscope(&nd_na->nd_na_target); /* XXX */ 995 996 /* 997 * "tlladdr" indicates NS's condition for adding tlladdr or not. 998 * see nd6_ns_input() for details. 999 * Basically, if NS packet is sent to unicast/anycast addr, 1000 * target lladdr option SHOULD NOT be included. 1001 */ 1002 if (tlladdr) { 1003 /* 1004 * sdl0 != NULL indicates proxy NA. If we do proxy, use 1005 * lladdr in sdl0. If we are not proxying (sending NA for 1006 * my address) use lladdr configured for the interface. 1007 */ 1008 if (sdl0 == NULL) { 1009#ifdef DEV_CARP 1010 if (ifp->if_carp) 1011 mac = carp_macmatch6(ifp->if_carp, m, taddr6); 1012 if (mac == NULL) 1013 mac = nd6_ifptomac(ifp); 1014#else 1015 mac = nd6_ifptomac(ifp); 1016#endif 1017 } else if (sdl0->sa_family == AF_LINK) { 1018 struct sockaddr_dl *sdl; 1019 sdl = (struct sockaddr_dl *)sdl0; 1020 if (sdl->sdl_alen == ifp->if_addrlen) 1021 mac = LLADDR(sdl); 1022 } 1023 } 1024 if (tlladdr && mac) { 1025 int optlen = sizeof(struct nd_opt_hdr) + ifp->if_addrlen; 1026 struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)(nd_na + 1); 1027 1028 /* roundup to 8 bytes alignment! */ 1029 optlen = (optlen + 7) & ~7; 1030 1031 m->m_pkthdr.len += optlen; 1032 m->m_len += optlen; 1033 icmp6len += optlen; 1034 bzero((caddr_t)nd_opt, optlen); 1035 nd_opt->nd_opt_type = ND_OPT_TARGET_LINKADDR; 1036 nd_opt->nd_opt_len = optlen >> 3; 1037 bcopy(mac, (caddr_t)(nd_opt + 1), ifp->if_addrlen); 1038 } else 1039 flags &= ~ND_NA_FLAG_OVERRIDE; 1040 1041 ip6->ip6_plen = htons((u_short)icmp6len); 1042 nd_na->nd_na_flags_reserved = flags; 1043 nd_na->nd_na_cksum = 0; 1044 nd_na->nd_na_cksum = 1045 in6_cksum(m, IPPROTO_ICMPV6, sizeof(struct ip6_hdr), icmp6len); 1046 1047 ip6_output(m, NULL, &ro, 0, &im6o, NULL, NULL); 1048 icmp6_ifstat_inc(ifp, ifs6_out_msg); 1049 icmp6_ifstat_inc(ifp, ifs6_out_neighboradvert); 1050 V_icmp6stat.icp6s_outhist[ND_NEIGHBOR_ADVERT]++; 1051 1052 if (ro.ro_rt) { /* we don't cache this route. */ 1053 RTFREE(ro.ro_rt); 1054 } 1055 return; 1056 1057 bad: 1058 if (ro.ro_rt) { 1059 RTFREE(ro.ro_rt); 1060 } 1061 m_freem(m); 1062 return; 1063} 1064 1065caddr_t 1066nd6_ifptomac(struct ifnet *ifp) 1067{ 1068 switch (ifp->if_type) { 1069 case IFT_ARCNET: 1070 case IFT_ETHER: 1071 case IFT_FDDI: 1072 case IFT_IEEE1394: 1073#ifdef IFT_L2VLAN 1074 case IFT_L2VLAN: 1075#endif 1076#ifdef IFT_IEEE80211 1077 case IFT_IEEE80211: 1078#endif 1079#ifdef IFT_CARP 1080 case IFT_CARP: 1081#endif 1082 case IFT_BRIDGE: 1083 case IFT_ISO88025: 1084 return IF_LLADDR(ifp); 1085 default: 1086 return NULL; 1087 } 1088} 1089 1090TAILQ_HEAD(dadq_head, dadq); 1091struct dadq { 1092 TAILQ_ENTRY(dadq) dad_list; 1093 struct ifaddr *dad_ifa; 1094 int dad_count; /* max NS to send */ 1095 int dad_ns_tcount; /* # of trials to send NS */ 1096 int dad_ns_ocount; /* NS sent so far */ 1097 int dad_ns_icount; 1098 int dad_na_icount; 1099 struct callout dad_timer_ch; 1100}; 1101 1102#ifdef VIMAGE_GLOBALS 1103static struct dadq_head dadq; 1104int dad_init; 1105#endif 1106 1107static struct dadq * 1108nd6_dad_find(struct ifaddr *ifa) 1109{ 1110 INIT_VNET_INET6(curvnet); 1111 struct dadq *dp; 1112 1113 for (dp = V_dadq.tqh_first; dp; dp = dp->dad_list.tqe_next) { 1114 if (dp->dad_ifa == ifa) 1115 return dp; 1116 } 1117 return NULL; 1118} 1119 1120static void 1121nd6_dad_starttimer(struct dadq *dp, int ticks) 1122{ 1123 1124 callout_reset(&dp->dad_timer_ch, ticks, 1125 (void (*)(void *))nd6_dad_timer, (void *)dp->dad_ifa); 1126} 1127 1128static void 1129nd6_dad_stoptimer(struct dadq *dp) 1130{ 1131 1132 callout_stop(&dp->dad_timer_ch); 1133} 1134 1135/* 1136 * Start Duplicate Address Detection (DAD) for specified interface address. 1137 */ 1138void 1139nd6_dad_start(struct ifaddr *ifa, int delay) 1140{ 1141 INIT_VNET_INET6(curvnet); 1142 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1143 struct dadq *dp; 1144 char ip6buf[INET6_ADDRSTRLEN]; 1145 1146 if (!V_dad_init) { 1147 TAILQ_INIT(&V_dadq); 1148 V_dad_init++; 1149 } 1150 1151 /* 1152 * If we don't need DAD, don't do it. 1153 * There are several cases: 1154 * - DAD is disabled (ip6_dad_count == 0) 1155 * - the interface address is anycast 1156 */ 1157 if (!(ia->ia6_flags & IN6_IFF_TENTATIVE)) { 1158 log(LOG_DEBUG, 1159 "nd6_dad_start: called with non-tentative address " 1160 "%s(%s)\n", 1161 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr), 1162 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1163 return; 1164 } 1165 if (ia->ia6_flags & IN6_IFF_ANYCAST) { 1166 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1167 return; 1168 } 1169 if (!V_ip6_dad_count) { 1170 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1171 return; 1172 } 1173 if (ifa->ifa_ifp == NULL) 1174 panic("nd6_dad_start: ifa->ifa_ifp == NULL"); 1175 if (!(ifa->ifa_ifp->if_flags & IFF_UP)) { 1176 return; 1177 } 1178 if (nd6_dad_find(ifa) != NULL) { 1179 /* DAD already in progress */ 1180 return; 1181 } 1182 1183 dp = malloc(sizeof(*dp), M_IP6NDP, M_NOWAIT); 1184 if (dp == NULL) { 1185 log(LOG_ERR, "nd6_dad_start: memory allocation failed for " 1186 "%s(%s)\n", 1187 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr), 1188 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1189 return; 1190 } 1191 bzero(dp, sizeof(*dp)); 1192 callout_init(&dp->dad_timer_ch, 0); 1193 TAILQ_INSERT_TAIL(&V_dadq, (struct dadq *)dp, dad_list); 1194 1195 nd6log((LOG_DEBUG, "%s: starting DAD for %s\n", if_name(ifa->ifa_ifp), 1196 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr))); 1197 1198 /* 1199 * Send NS packet for DAD, ip6_dad_count times. 1200 * Note that we must delay the first transmission, if this is the 1201 * first packet to be sent from the interface after interface 1202 * (re)initialization. 1203 */ 1204 dp->dad_ifa = ifa; 1205 IFAREF(ifa); /* just for safety */ 1206 dp->dad_count = V_ip6_dad_count; 1207 dp->dad_ns_icount = dp->dad_na_icount = 0; 1208 dp->dad_ns_ocount = dp->dad_ns_tcount = 0; 1209 if (delay == 0) { 1210 nd6_dad_ns_output(dp, ifa); 1211 nd6_dad_starttimer(dp, 1212 (long)ND_IFINFO(ifa->ifa_ifp)->retrans * hz / 1000); 1213 } else { 1214 nd6_dad_starttimer(dp, delay); 1215 } 1216} 1217 1218/* 1219 * terminate DAD unconditionally. used for address removals. 1220 */ 1221void 1222nd6_dad_stop(struct ifaddr *ifa) 1223{ 1224 INIT_VNET_INET6(curvnet); 1225 struct dadq *dp; 1226 1227 if (!V_dad_init) 1228 return; 1229 dp = nd6_dad_find(ifa); 1230 if (!dp) { 1231 /* DAD wasn't started yet */ 1232 return; 1233 } 1234 1235 nd6_dad_stoptimer(dp); 1236 1237 TAILQ_REMOVE(&V_dadq, (struct dadq *)dp, dad_list); 1238 free(dp, M_IP6NDP); 1239 dp = NULL; 1240 IFAFREE(ifa); 1241} 1242 1243static void 1244nd6_dad_timer(struct ifaddr *ifa) 1245{ 1246 CURVNET_SET(dp->dad_vnet); 1247 INIT_VNET_INET6(curvnet); 1248 int s; 1249 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1250 struct dadq *dp; 1251 char ip6buf[INET6_ADDRSTRLEN]; 1252 1253 s = splnet(); /* XXX */ 1254 1255 /* Sanity check */ 1256 if (ia == NULL) { 1257 log(LOG_ERR, "nd6_dad_timer: called with null parameter\n"); 1258 goto done; 1259 } 1260 dp = nd6_dad_find(ifa); 1261 if (dp == NULL) { 1262 log(LOG_ERR, "nd6_dad_timer: DAD structure not found\n"); 1263 goto done; 1264 } 1265 if (ia->ia6_flags & IN6_IFF_DUPLICATED) { 1266 log(LOG_ERR, "nd6_dad_timer: called with duplicated address " 1267 "%s(%s)\n", 1268 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr), 1269 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1270 goto done; 1271 } 1272 if ((ia->ia6_flags & IN6_IFF_TENTATIVE) == 0) { 1273 log(LOG_ERR, "nd6_dad_timer: called with non-tentative address " 1274 "%s(%s)\n", 1275 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr), 1276 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1277 goto done; 1278 } 1279 1280 /* timeouted with IFF_{RUNNING,UP} check */ 1281 if (dp->dad_ns_tcount > V_dad_maxtry) { 1282 nd6log((LOG_INFO, "%s: could not run DAD, driver problem?\n", 1283 if_name(ifa->ifa_ifp))); 1284 1285 TAILQ_REMOVE(&V_dadq, (struct dadq *)dp, dad_list); 1286 free(dp, M_IP6NDP); 1287 dp = NULL; 1288 IFAFREE(ifa); 1289 goto done; 1290 } 1291 1292 /* Need more checks? */ 1293 if (dp->dad_ns_ocount < dp->dad_count) { 1294 /* 1295 * We have more NS to go. Send NS packet for DAD. 1296 */ 1297 nd6_dad_ns_output(dp, ifa); 1298 nd6_dad_starttimer(dp, 1299 (long)ND_IFINFO(ifa->ifa_ifp)->retrans * hz / 1000); 1300 } else { 1301 /* 1302 * We have transmitted sufficient number of DAD packets. 1303 * See what we've got. 1304 */ 1305 int duplicate; 1306 1307 duplicate = 0; 1308 1309 if (dp->dad_na_icount) { 1310 /* 1311 * the check is in nd6_dad_na_input(), 1312 * but just in case 1313 */ 1314 duplicate++; 1315 } 1316 1317 if (dp->dad_ns_icount) { 1318 /* We've seen NS, means DAD has failed. */ 1319 duplicate++; 1320 } 1321 1322 if (duplicate) { 1323 /* (*dp) will be freed in nd6_dad_duplicated() */ 1324 dp = NULL; 1325 nd6_dad_duplicated(ifa); 1326 } else { 1327 /* 1328 * We are done with DAD. No NA came, no NS came. 1329 * No duplicate address found. 1330 */ 1331 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1332 1333 nd6log((LOG_DEBUG, 1334 "%s: DAD complete for %s - no duplicates found\n", 1335 if_name(ifa->ifa_ifp), 1336 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr))); 1337 1338 TAILQ_REMOVE(&V_dadq, (struct dadq *)dp, dad_list); 1339 free(dp, M_IP6NDP); 1340 dp = NULL; 1341 IFAFREE(ifa); 1342 } 1343 } 1344 1345done: 1346 splx(s); 1347 CURVNET_RESTORE(); 1348} 1349 1350void 1351nd6_dad_duplicated(struct ifaddr *ifa) 1352{ 1353 INIT_VNET_INET6(curvnet); 1354 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1355 struct ifnet *ifp; 1356 struct dadq *dp; 1357 char ip6buf[INET6_ADDRSTRLEN]; 1358 1359 dp = nd6_dad_find(ifa); 1360 if (dp == NULL) { 1361 log(LOG_ERR, "nd6_dad_duplicated: DAD structure not found\n"); 1362 return; 1363 } 1364 1365 log(LOG_ERR, "%s: DAD detected duplicate IPv6 address %s: " 1366 "NS in/out=%d/%d, NA in=%d\n", 1367 if_name(ifa->ifa_ifp), ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr), 1368 dp->dad_ns_icount, dp->dad_ns_ocount, dp->dad_na_icount); 1369 1370 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1371 ia->ia6_flags |= IN6_IFF_DUPLICATED; 1372 1373 /* We are done with DAD, with duplicate address found. (failure) */ 1374 nd6_dad_stoptimer(dp); 1375 1376 ifp = ifa->ifa_ifp; 1377 log(LOG_ERR, "%s: DAD complete for %s - duplicate found\n", 1378 if_name(ifp), ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr)); 1379 log(LOG_ERR, "%s: manual intervention required\n", 1380 if_name(ifp)); 1381 1382 /* 1383 * If the address is a link-local address formed from an interface 1384 * identifier based on the hardware address which is supposed to be 1385 * uniquely assigned (e.g., EUI-64 for an Ethernet interface), IP 1386 * operation on the interface SHOULD be disabled. 1387 * [rfc2462bis-03 Section 5.4.5] 1388 */ 1389 if (IN6_IS_ADDR_LINKLOCAL(&ia->ia_addr.sin6_addr)) { 1390 struct in6_addr in6; 1391 1392 /* 1393 * To avoid over-reaction, we only apply this logic when we are 1394 * very sure that hardware addresses are supposed to be unique. 1395 */ 1396 switch (ifp->if_type) { 1397 case IFT_ETHER: 1398 case IFT_FDDI: 1399 case IFT_ATM: 1400 case IFT_IEEE1394: 1401#ifdef IFT_IEEE80211 1402 case IFT_IEEE80211: 1403#endif 1404 in6 = ia->ia_addr.sin6_addr; 1405 if (in6_get_hw_ifid(ifp, &in6) == 0 && 1406 IN6_ARE_ADDR_EQUAL(&ia->ia_addr.sin6_addr, &in6)) { 1407 ND_IFINFO(ifp)->flags |= ND6_IFF_IFDISABLED; 1408 log(LOG_ERR, "%s: possible hardware address " 1409 "duplication detected, disable IPv6\n", 1410 if_name(ifp)); 1411 } 1412 break; 1413 } 1414 } 1415 1416 TAILQ_REMOVE(&V_dadq, (struct dadq *)dp, dad_list); 1417 free(dp, M_IP6NDP); 1418 dp = NULL; 1419 IFAFREE(ifa); 1420} 1421 1422static void 1423nd6_dad_ns_output(struct dadq *dp, struct ifaddr *ifa) 1424{ 1425 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1426 struct ifnet *ifp = ifa->ifa_ifp; 1427 1428 dp->dad_ns_tcount++; 1429 if ((ifp->if_flags & IFF_UP) == 0) { 1430 return; 1431 } 1432 if ((ifp->if_drv_flags & IFF_DRV_RUNNING) == 0) { 1433 return; 1434 } 1435 1436 dp->dad_ns_ocount++; 1437 nd6_ns_output(ifp, NULL, &ia->ia_addr.sin6_addr, NULL, 1); 1438} 1439 1440static void 1441nd6_dad_ns_input(struct ifaddr *ifa) 1442{ 1443 INIT_VNET_INET6(curvnet); 1444 struct in6_ifaddr *ia; 1445 struct ifnet *ifp; 1446 const struct in6_addr *taddr6; 1447 struct dadq *dp; 1448 int duplicate; 1449 1450 if (ifa == NULL) 1451 panic("ifa == NULL in nd6_dad_ns_input"); 1452 1453 ia = (struct in6_ifaddr *)ifa; 1454 ifp = ifa->ifa_ifp; 1455 taddr6 = &ia->ia_addr.sin6_addr; 1456 duplicate = 0; 1457 dp = nd6_dad_find(ifa); 1458 1459 /* Quickhack - completely ignore DAD NS packets */ 1460 if (V_dad_ignore_ns) { 1461 char ip6buf[INET6_ADDRSTRLEN]; 1462 nd6log((LOG_INFO, 1463 "nd6_dad_ns_input: ignoring DAD NS packet for " 1464 "address %s(%s)\n", ip6_sprintf(ip6buf, taddr6), 1465 if_name(ifa->ifa_ifp))); 1466 return; 1467 } 1468 1469 /* 1470 * if I'm yet to start DAD, someone else started using this address 1471 * first. I have a duplicate and you win. 1472 */ 1473 if (dp == NULL || dp->dad_ns_ocount == 0) 1474 duplicate++; 1475 1476 /* XXX more checks for loopback situation - see nd6_dad_timer too */ 1477 1478 if (duplicate) { 1479 dp = NULL; /* will be freed in nd6_dad_duplicated() */ 1480 nd6_dad_duplicated(ifa); 1481 } else { 1482 /* 1483 * not sure if I got a duplicate. 1484 * increment ns count and see what happens. 1485 */ 1486 if (dp) 1487 dp->dad_ns_icount++; 1488 } 1489} 1490 1491static void 1492nd6_dad_na_input(struct ifaddr *ifa) 1493{ 1494 struct dadq *dp; 1495 1496 if (ifa == NULL) 1497 panic("ifa == NULL in nd6_dad_na_input"); 1498 1499 dp = nd6_dad_find(ifa); 1500 if (dp) 1501 dp->dad_na_icount++; 1502 1503 /* remove the address. */ 1504 nd6_dad_duplicated(ifa); 1505} 1506