1 /* $NetBSD: nd6_nbr.c,v 1.43 2002/09/23 05:51:16 simonb Exp $ */ 2 /* $KAME: nd6_nbr.c,v 1.61 2001/02/10 16:06:14 jinmei Exp $ */ 3 4 /* 5 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project. 6 * All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. Neither the name of the project nor the names of its contributors 17 * may be used to endorse or promote products derived from this software 18 * without specific prior written permission. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND 21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE 24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30 * SUCH DAMAGE. 31 */ 32 33 #include <sys/cdefs.h> 34 __KERNEL_RCSID(0, "$NetBSD: nd6_nbr.c,v 1.43 2002/09/23 05:51:16 simonb Exp $"); 35 36 #include "opt_inet.h" 37 #include "opt_ipsec.h" 38 39 #include <sys/param.h> 40 #include <sys/systm.h> 41 #include <sys/malloc.h> 42 #include <sys/mbuf.h> 43 #include <sys/socket.h> 44 #include <sys/sockio.h> 45 #include <sys/time.h> 46 #include <sys/kernel.h> 47 #include <sys/errno.h> 48 #include <sys/ioctl.h> 49 #include <sys/syslog.h> 50 #include <sys/queue.h> 51 #include <sys/callout.h> 52 53 #include <net/if.h> 54 #include <net/if_types.h> 55 #include <net/if_dl.h> 56 #include <net/route.h> 57 58 #include <netinet/in.h> 59 #include <netinet/in_var.h> 60 #include <netinet6/in6_var.h> 61 #include <netinet/ip6.h> 62 #include <netinet6/ip6_var.h> 63 #include <netinet6/nd6.h> 64 #include <netinet/icmp6.h> 65 66 #ifdef IPSEC 67 #include <netinet6/ipsec.h> 68 #endif 69 70 #include <net/net_osdep.h> 71 72 #define SDL(s) ((struct sockaddr_dl *)s) 73 74 struct dadq; 75 static struct dadq *nd6_dad_find __P((struct ifaddr *)); 76 static void nd6_dad_starttimer __P((struct dadq *, int)); 77 static void nd6_dad_stoptimer __P((struct dadq *)); 78 static void nd6_dad_timer __P((struct ifaddr *)); 79 static void nd6_dad_ns_output __P((struct dadq *, struct ifaddr *)); 80 static void nd6_dad_ns_input __P((struct ifaddr *)); 81 static void nd6_dad_na_input __P((struct ifaddr *)); 82 83 static int dad_ignore_ns = 0; /* ignore NS in DAD - specwise incorrect*/ 84 static int dad_maxtry = 15; /* max # of *tries* to transmit DAD packet */ 85 86 /* 87 * Input an Neighbor Solicitation Message. 88 * 89 * Based on RFC 2461 90 * Based on RFC 2462 (duplicated address detection) 91 */ 92 void 93 nd6_ns_input(m, off, icmp6len) 94 struct mbuf *m; 95 int off, icmp6len; 96 { 97 struct ifnet *ifp = m->m_pkthdr.rcvif; 98 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 99 struct nd_neighbor_solicit *nd_ns; 100 struct in6_addr saddr6 = ip6->ip6_src; 101 struct in6_addr daddr6 = ip6->ip6_dst; 102 struct in6_addr taddr6; 103 struct in6_addr myaddr6; 104 char *lladdr = NULL; 105 struct ifaddr *ifa; 106 int lladdrlen = 0; 107 int anycast = 0, proxy = 0, tentative = 0; 108 int router = ip6_forwarding; 109 int tlladdr; 110 union nd_opts ndopts; 111 struct sockaddr_dl *proxydl = NULL; 112 113 #ifndef PULLDOWN_TEST 114 IP6_EXTHDR_CHECK(m, off, icmp6len,); 115 nd_ns = (struct nd_neighbor_solicit *)((caddr_t)ip6 + off); 116 #else 117 IP6_EXTHDR_GET(nd_ns, struct nd_neighbor_solicit *, m, off, icmp6len); 118 if (nd_ns == NULL) { 119 icmp6stat.icp6s_tooshort++; 120 return; 121 } 122 #endif 123 ip6 = mtod(m, struct ip6_hdr *); /* adjust pointer for safety */ 124 taddr6 = nd_ns->nd_ns_target; 125 126 if (ip6->ip6_hlim != 255) { 127 nd6log((LOG_ERR, 128 "nd6_ns_input: invalid hlim (%d) from %s to %s on %s\n", 129 ip6->ip6_hlim, ip6_sprintf(&ip6->ip6_src), 130 ip6_sprintf(&ip6->ip6_dst), if_name(ifp))); 131 goto bad; 132 } 133 134 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) { 135 /* dst has to be solicited node multicast address. */ 136 /* don't check ifindex portion */ 137 if (daddr6.s6_addr16[0] == IPV6_ADDR_INT16_MLL && 138 daddr6.s6_addr32[1] == 0 && 139 daddr6.s6_addr32[2] == IPV6_ADDR_INT32_ONE && 140 daddr6.s6_addr8[12] == 0xff) { 141 ; /* good */ 142 } else { 143 nd6log((LOG_INFO, "nd6_ns_input: bad DAD packet " 144 "(wrong ip6 dst)\n")); 145 goto bad; 146 } 147 } 148 149 if (IN6_IS_ADDR_MULTICAST(&taddr6)) { 150 nd6log((LOG_INFO, "nd6_ns_input: bad NS target (multicast)\n")); 151 goto bad; 152 } 153 154 if (IN6_IS_SCOPE_LINKLOCAL(&taddr6)) 155 taddr6.s6_addr16[1] = htons(ifp->if_index); 156 157 icmp6len -= sizeof(*nd_ns); 158 nd6_option_init(nd_ns + 1, icmp6len, &ndopts); 159 if (nd6_options(&ndopts) < 0) { 160 nd6log((LOG_INFO, 161 "nd6_ns_input: invalid ND option, ignored\n")); 162 /* nd6_options have incremented stats */ 163 goto freeit; 164 } 165 166 if (ndopts.nd_opts_src_lladdr) { 167 lladdr = (char *)(ndopts.nd_opts_src_lladdr + 1); 168 lladdrlen = ndopts.nd_opts_src_lladdr->nd_opt_len << 3; 169 } 170 171 if (IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_src) && lladdr) { 172 nd6log((LOG_INFO, "nd6_ns_input: bad DAD packet " 173 "(link-layer address option)\n")); 174 goto bad; 175 } 176 177 /* 178 * Attaching target link-layer address to the NA? 179 * (RFC 2461 7.2.4) 180 * 181 * NS IP dst is unicast/anycast MUST NOT add 182 * NS IP dst is solicited-node multicast MUST add 183 * 184 * In implementation, we add target link-layer address by default. 185 * We do not add one in MUST NOT cases. 186 */ 187 #if 0 /* too much! */ 188 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &daddr6); 189 if (ifa && (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_ANYCAST)) 190 tlladdr = 0; 191 else 192 #endif 193 if (!IN6_IS_ADDR_MULTICAST(&daddr6)) 194 tlladdr = 0; 195 else 196 tlladdr = 1; 197 198 /* 199 * Target address (taddr6) must be either: 200 * (1) Valid unicast/anycast address for my receiving interface, 201 * (2) Unicast address for which I'm offering proxy service, or 202 * (3) "tentative" address on which DAD is being performed. 203 */ 204 /* (1) and (3) check. */ 205 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &taddr6); 206 207 /* (2) check. */ 208 if (!ifa) { 209 struct rtentry *rt; 210 struct sockaddr_in6 tsin6; 211 212 bzero(&tsin6, sizeof tsin6); 213 tsin6.sin6_len = sizeof(struct sockaddr_in6); 214 tsin6.sin6_family = AF_INET6; 215 tsin6.sin6_addr = taddr6; 216 217 rt = rtalloc1((struct sockaddr *)&tsin6, 0); 218 if (rt && (rt->rt_flags & RTF_ANNOUNCE) != 0 && 219 rt->rt_gateway->sa_family == AF_LINK) { 220 /* 221 * proxy NDP for single entry 222 */ 223 ifa = (struct ifaddr *)in6ifa_ifpforlinklocal(ifp, 224 IN6_IFF_NOTREADY|IN6_IFF_ANYCAST); 225 if (ifa) { 226 proxy = 1; 227 proxydl = SDL(rt->rt_gateway); 228 router = 0; /* XXX */ 229 } 230 } 231 if (rt) 232 rtfree(rt); 233 } 234 if (!ifa) { 235 /* 236 * We've got an NS packet, and we don't have that adddress 237 * assigned for us. We MUST silently ignore it. 238 * See RFC2461 7.2.3. 239 */ 240 goto freeit; 241 } 242 myaddr6 = *IFA_IN6(ifa); 243 anycast = ((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_ANYCAST; 244 tentative = ((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_TENTATIVE; 245 if (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_DUPLICATED) 246 goto freeit; 247 248 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) { 249 nd6log((LOG_INFO, "nd6_ns_input: lladdrlen mismatch for %s " 250 "(if %d, NS packet %d)\n", 251 ip6_sprintf(&taddr6), ifp->if_addrlen, lladdrlen - 2)); 252 goto bad; 253 } 254 255 if (IN6_ARE_ADDR_EQUAL(&myaddr6, &saddr6)) { 256 nd6log((LOG_INFO, "nd6_ns_input: duplicate IP6 address %s\n", 257 ip6_sprintf(&saddr6))); 258 goto freeit; 259 } 260 261 /* 262 * We have neighbor solicitation packet, with target address equals to 263 * one of my tentative address. 264 * 265 * src addr how to process? 266 * --- --- 267 * multicast of course, invalid (rejected in ip6_input) 268 * unicast somebody is doing address resolution -> ignore 269 * unspec dup address detection 270 * 271 * The processing is defined in RFC 2462. 272 */ 273 if (tentative) { 274 /* 275 * If source address is unspecified address, it is for 276 * duplicated address detection. 277 * 278 * If not, the packet is for addess resolution; 279 * silently ignore it. 280 */ 281 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) 282 nd6_dad_ns_input(ifa); 283 284 goto freeit; 285 } 286 287 /* 288 * If the source address is unspecified address, entries must not 289 * be created or updated. 290 * It looks that sender is performing DAD. Output NA toward 291 * all-node multicast address, to tell the sender that I'm using 292 * the address. 293 * S bit ("solicited") must be zero. 294 */ 295 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) { 296 saddr6 = in6addr_linklocal_allnodes; 297 saddr6.s6_addr16[1] = htons(ifp->if_index); 298 nd6_na_output(ifp, &saddr6, &taddr6, 299 ((anycast || proxy || !tlladdr) ? 0 : ND_NA_FLAG_OVERRIDE) | 300 (router ? ND_NA_FLAG_ROUTER : 0), 301 tlladdr, (struct sockaddr *)proxydl); 302 goto freeit; 303 } 304 305 nd6_cache_lladdr(ifp, &saddr6, lladdr, lladdrlen, ND_NEIGHBOR_SOLICIT, 0); 306 307 nd6_na_output(ifp, &saddr6, &taddr6, 308 ((anycast || proxy || !tlladdr) ? 0 : ND_NA_FLAG_OVERRIDE) | 309 (router ? ND_NA_FLAG_ROUTER : 0) | ND_NA_FLAG_SOLICITED, 310 tlladdr, (struct sockaddr *)proxydl); 311 freeit: 312 m_freem(m); 313 return; 314 315 bad: 316 nd6log((LOG_ERR, "nd6_ns_input: src=%s\n", ip6_sprintf(&saddr6))); 317 nd6log((LOG_ERR, "nd6_ns_input: dst=%s\n", ip6_sprintf(&daddr6))); 318 nd6log((LOG_ERR, "nd6_ns_input: tgt=%s\n", ip6_sprintf(&taddr6))); 319 icmp6stat.icp6s_badns++; 320 m_freem(m); 321 } 322 323 /* 324 * Output an Neighbor Solicitation Message. Caller specifies: 325 * - ICMP6 header source IP6 address 326 * - ND6 header target IP6 address 327 * - ND6 header source datalink address 328 * 329 * Based on RFC 2461 330 * Based on RFC 2462 (duplicated address detection) 331 */ 332 void 333 nd6_ns_output(ifp, daddr6, taddr6, ln, dad) 334 struct ifnet *ifp; 335 const struct in6_addr *daddr6, *taddr6; 336 struct llinfo_nd6 *ln; /* for source address determination */ 337 int dad; /* duplicated address detection */ 338 { 339 struct mbuf *m; 340 struct ip6_hdr *ip6; 341 struct nd_neighbor_solicit *nd_ns; 342 struct sockaddr_in6 src_sa, dst_sa; 343 struct ip6_moptions im6o; 344 int icmp6len; 345 int maxlen; 346 caddr_t mac; 347 struct route_in6 ro; 348 349 bzero(&ro, sizeof(ro)); 350 351 if (IN6_IS_ADDR_MULTICAST(taddr6)) 352 return; 353 354 /* estimate the size of message */ 355 maxlen = sizeof(*ip6) + sizeof(*nd_ns); 356 maxlen += (sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7; 357 #ifdef DIAGNOSTIC 358 if (max_linkhdr + maxlen >= MCLBYTES) { 359 printf("nd6_ns_output: max_linkhdr + maxlen >= MCLBYTES " 360 "(%d + %d > %d)\n", max_linkhdr, maxlen, MCLBYTES); 361 panic("nd6_ns_output: insufficient MCLBYTES"); 362 /* NOTREACHED */ 363 } 364 #endif 365 366 MGETHDR(m, M_DONTWAIT, MT_DATA); 367 if (m && max_linkhdr + maxlen >= MHLEN) { 368 MCLGET(m, M_DONTWAIT); 369 if ((m->m_flags & M_EXT) == 0) { 370 m_free(m); 371 m = NULL; 372 } 373 } 374 if (m == NULL) 375 return; 376 m->m_pkthdr.rcvif = NULL; 377 378 if (daddr6 == NULL || IN6_IS_ADDR_MULTICAST(daddr6)) { 379 m->m_flags |= M_MCAST; 380 im6o.im6o_multicast_ifp = ifp; 381 im6o.im6o_multicast_hlim = 255; 382 im6o.im6o_multicast_loop = 0; 383 } 384 385 icmp6len = sizeof(*nd_ns); 386 m->m_pkthdr.len = m->m_len = sizeof(*ip6) + icmp6len; 387 m->m_data += max_linkhdr; /* or MH_ALIGN() equivalent? */ 388 389 /* fill neighbor solicitation packet */ 390 ip6 = mtod(m, struct ip6_hdr *); 391 ip6->ip6_flow = 0; 392 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 393 ip6->ip6_vfc |= IPV6_VERSION; 394 /* ip6->ip6_plen will be set later */ 395 ip6->ip6_nxt = IPPROTO_ICMPV6; 396 ip6->ip6_hlim = 255; 397 /* determine the source and destination addresses */ 398 bzero(&src_sa, sizeof(src_sa)); 399 bzero(&dst_sa, sizeof(dst_sa)); 400 src_sa.sin6_family = dst_sa.sin6_family = AF_INET6; 401 src_sa.sin6_len = dst_sa.sin6_len = sizeof(struct sockaddr_in6); 402 if (daddr6) 403 dst_sa.sin6_addr = *daddr6; 404 else { 405 dst_sa.sin6_addr.s6_addr16[0] = IPV6_ADDR_INT16_MLL; 406 dst_sa.sin6_addr.s6_addr16[1] = htons(ifp->if_index); 407 dst_sa.sin6_addr.s6_addr32[1] = 0; 408 dst_sa.sin6_addr.s6_addr32[2] = IPV6_ADDR_INT32_ONE; 409 dst_sa.sin6_addr.s6_addr32[3] = taddr6->s6_addr32[3]; 410 dst_sa.sin6_addr.s6_addr8[12] = 0xff; 411 } 412 ip6->ip6_dst = dst_sa.sin6_addr; 413 if (!dad) { 414 /* 415 * RFC2461 7.2.2: 416 * "If the source address of the packet prompting the 417 * solicitation is the same as one of the addresses assigned 418 * to the outgoing interface, that address SHOULD be placed 419 * in the IP Source Address of the outgoing solicitation. 420 * Otherwise, any one of the addresses assigned to the 421 * interface should be used." 422 * 423 * We use the source address for the prompting packet 424 * (saddr6), if: 425 * - saddr6 is given from the caller (by giving "ln"), and 426 * - saddr6 belongs to the outgoing interface. 427 * Otherwise, we perform the source address selection as usual. 428 */ 429 struct ip6_hdr *hip6; /* hold ip6 */ 430 struct in6_addr *saddr6; 431 432 if (ln && ln->ln_hold) { 433 hip6 = mtod(ln->ln_hold, struct ip6_hdr *); 434 /* XXX pullup? */ 435 if (sizeof(*hip6) < ln->ln_hold->m_len) 436 saddr6 = &hip6->ip6_src; 437 else 438 saddr6 = NULL; 439 } else 440 saddr6 = NULL; 441 if (saddr6 && in6ifa_ifpwithaddr(ifp, saddr6)) 442 src_sa.sin6_addr = *saddr6; 443 else { 444 struct in6_addr *src0; 445 int error; 446 447 bcopy(&dst_sa, &ro.ro_dst, sizeof(dst_sa)); 448 src0 = in6_selectsrc(&dst_sa, NULL, NULL, &ro, NULL, 449 &error); 450 if (src0 == NULL) { 451 nd6log((LOG_DEBUG, 452 "nd6_ns_output: source can't be " 453 "determined: dst=%s, error=%d\n", 454 ip6_sprintf(&dst_sa.sin6_addr), error)); 455 goto bad; 456 } 457 src_sa.sin6_addr = *src0; 458 } 459 } else { 460 /* 461 * Source address for DAD packet must always be IPv6 462 * unspecified address. (0::0) 463 * We actually don't have to 0-clear the address (we did it 464 * above), but we do so here explicitly to make the intention 465 * clearer. 466 */ 467 bzero(&src_sa.sin6_addr, sizeof(src_sa.sin6_addr)); 468 } 469 ip6->ip6_src = src_sa.sin6_addr; 470 nd_ns = (struct nd_neighbor_solicit *)(ip6 + 1); 471 nd_ns->nd_ns_type = ND_NEIGHBOR_SOLICIT; 472 nd_ns->nd_ns_code = 0; 473 nd_ns->nd_ns_reserved = 0; 474 nd_ns->nd_ns_target = *taddr6; 475 476 if (IN6_IS_SCOPE_LINKLOCAL(&nd_ns->nd_ns_target)) 477 nd_ns->nd_ns_target.s6_addr16[1] = 0; 478 479 /* 480 * Add source link-layer address option. 481 * 482 * spec implementation 483 * --- --- 484 * DAD packet MUST NOT do not add the option 485 * there's no link layer address: 486 * impossible do not add the option 487 * there's link layer address: 488 * Multicast NS MUST add one add the option 489 * Unicast NS SHOULD add one add the option 490 */ 491 if (!dad && (mac = nd6_ifptomac(ifp))) { 492 int optlen = sizeof(struct nd_opt_hdr) + ifp->if_addrlen; 493 struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)(nd_ns + 1); 494 /* 8 byte alignments... */ 495 optlen = (optlen + 7) & ~7; 496 497 m->m_pkthdr.len += optlen; 498 m->m_len += optlen; 499 icmp6len += optlen; 500 bzero((caddr_t)nd_opt, optlen); 501 nd_opt->nd_opt_type = ND_OPT_SOURCE_LINKADDR; 502 nd_opt->nd_opt_len = optlen >> 3; 503 bcopy(mac, (caddr_t)(nd_opt + 1), ifp->if_addrlen); 504 } 505 506 ip6->ip6_plen = htons((u_short)icmp6len); 507 nd_ns->nd_ns_cksum = 0; 508 nd_ns->nd_ns_cksum = 509 in6_cksum(m, IPPROTO_ICMPV6, sizeof(*ip6), icmp6len); 510 511 #ifdef IPSEC 512 /* Don't lookup socket */ 513 (void)ipsec_setsocket(m, NULL); 514 #endif 515 ip6_output(m, NULL, &ro, dad ? IPV6_UNSPECSRC : 0, &im6o, NULL); 516 icmp6_ifstat_inc(ifp, ifs6_out_msg); 517 icmp6_ifstat_inc(ifp, ifs6_out_neighborsolicit); 518 icmp6stat.icp6s_outhist[ND_NEIGHBOR_SOLICIT]++; 519 520 if (ro.ro_rt) { /* we don't cache this route. */ 521 RTFREE(ro.ro_rt); 522 } 523 return; 524 525 bad: 526 if (ro.ro_rt) { 527 RTFREE(ro.ro_rt); 528 } 529 m_freem(m); 530 return; 531 } 532 533 /* 534 * Neighbor advertisement input handling. 535 * 536 * Based on RFC 2461 537 * Based on RFC 2462 (duplicated address detection) 538 * 539 * the following items are not implemented yet: 540 * - proxy advertisement delay rule (RFC2461 7.2.8, last paragraph, SHOULD) 541 * - anycast advertisement delay rule (RFC2461 7.2.7, SHOULD) 542 */ 543 void 544 nd6_na_input(m, off, icmp6len) 545 struct mbuf *m; 546 int off, icmp6len; 547 { 548 struct ifnet *ifp = m->m_pkthdr.rcvif; 549 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 550 struct nd_neighbor_advert *nd_na; 551 #if 0 552 struct in6_addr saddr6 = ip6->ip6_src; 553 #endif 554 struct in6_addr daddr6 = ip6->ip6_dst; 555 struct in6_addr taddr6; 556 int flags; 557 int is_router; 558 int is_solicited; 559 int is_override; 560 char *lladdr = NULL; 561 int lladdrlen = 0; 562 struct ifaddr *ifa; 563 struct llinfo_nd6 *ln; 564 struct rtentry *rt; 565 struct sockaddr_dl *sdl; 566 union nd_opts ndopts; 567 long time_second = time.tv_sec; 568 569 if (ip6->ip6_hlim != 255) { 570 nd6log((LOG_ERR, 571 "nd6_na_input: invalid hlim (%d) from %s to %s on %s\n", 572 ip6->ip6_hlim, ip6_sprintf(&ip6->ip6_src), 573 ip6_sprintf(&ip6->ip6_dst), if_name(ifp))); 574 goto bad; 575 } 576 577 #ifndef PULLDOWN_TEST 578 IP6_EXTHDR_CHECK(m, off, icmp6len,); 579 nd_na = (struct nd_neighbor_advert *)((caddr_t)ip6 + off); 580 #else 581 IP6_EXTHDR_GET(nd_na, struct nd_neighbor_advert *, m, off, icmp6len); 582 if (nd_na == NULL) { 583 icmp6stat.icp6s_tooshort++; 584 return; 585 } 586 #endif 587 taddr6 = nd_na->nd_na_target; 588 flags = nd_na->nd_na_flags_reserved; 589 is_router = ((flags & ND_NA_FLAG_ROUTER) != 0); 590 is_solicited = ((flags & ND_NA_FLAG_SOLICITED) != 0); 591 is_override = ((flags & ND_NA_FLAG_OVERRIDE) != 0); 592 593 if (IN6_IS_SCOPE_LINKLOCAL(&taddr6)) 594 taddr6.s6_addr16[1] = htons(ifp->if_index); 595 596 if (IN6_IS_ADDR_MULTICAST(&taddr6)) { 597 nd6log((LOG_ERR, 598 "nd6_na_input: invalid target address %s\n", 599 ip6_sprintf(&taddr6))); 600 goto bad; 601 } 602 if (is_solicited && IN6_IS_ADDR_MULTICAST(&daddr6)) { 603 nd6log((LOG_ERR, 604 "nd6_na_input: a solicited adv is multicasted\n")); 605 goto bad; 606 } 607 608 icmp6len -= sizeof(*nd_na); 609 nd6_option_init(nd_na + 1, icmp6len, &ndopts); 610 if (nd6_options(&ndopts) < 0) { 611 nd6log((LOG_INFO, 612 "nd6_na_input: invalid ND option, ignored\n")); 613 /* nd6_options have incremented stats */ 614 goto freeit; 615 } 616 617 if (ndopts.nd_opts_tgt_lladdr) { 618 lladdr = (char *)(ndopts.nd_opts_tgt_lladdr + 1); 619 lladdrlen = ndopts.nd_opts_tgt_lladdr->nd_opt_len << 3; 620 } 621 622 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &taddr6); 623 624 /* 625 * Target address matches one of my interface address. 626 * 627 * If my address is tentative, this means that there's somebody 628 * already using the same address as mine. This indicates DAD failure. 629 * This is defined in RFC 2462. 630 * 631 * Otherwise, process as defined in RFC 2461. 632 */ 633 if (ifa 634 && (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_TENTATIVE)) { 635 nd6_dad_na_input(ifa); 636 goto freeit; 637 } 638 639 /* Just for safety, maybe unnecessary. */ 640 if (ifa) { 641 log(LOG_ERR, 642 "nd6_na_input: duplicate IP6 address %s\n", 643 ip6_sprintf(&taddr6)); 644 goto freeit; 645 } 646 647 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) { 648 nd6log((LOG_INFO, "nd6_na_input: lladdrlen mismatch for %s " 649 "(if %d, NA packet %d)\n", ip6_sprintf(&taddr6), 650 ifp->if_addrlen, lladdrlen - 2)); 651 goto bad; 652 } 653 654 /* 655 * If no neighbor cache entry is found, NA SHOULD silently be 656 * discarded. 657 */ 658 rt = nd6_lookup(&taddr6, 0, ifp); 659 if ((rt == NULL) || 660 ((ln = (struct llinfo_nd6 *)rt->rt_llinfo) == NULL) || 661 ((sdl = SDL(rt->rt_gateway)) == NULL)) 662 goto freeit; 663 664 if (ln->ln_state == ND6_LLINFO_INCOMPLETE) { 665 /* 666 * If the link-layer has address, and no lladdr option came, 667 * discard the packet. 668 */ 669 if (ifp->if_addrlen && !lladdr) 670 goto freeit; 671 672 /* 673 * Record link-layer address, and update the state. 674 */ 675 sdl->sdl_alen = ifp->if_addrlen; 676 bcopy(lladdr, LLADDR(sdl), ifp->if_addrlen); 677 if (is_solicited) { 678 ln->ln_state = ND6_LLINFO_REACHABLE; 679 ln->ln_byhint = 0; 680 if (ln->ln_expire) 681 ln->ln_expire = time_second + 682 ND_IFINFO(rt->rt_ifp)->reachable; 683 } else { 684 ln->ln_state = ND6_LLINFO_STALE; 685 ln->ln_expire = time_second + nd6_gctimer; 686 } 687 if ((ln->ln_router = is_router) != 0) { 688 /* 689 * This means a router's state has changed from 690 * non-reachable to probably reachable, and might 691 * affect the status of associated prefixes.. 692 */ 693 pfxlist_onlink_check(); 694 } 695 } else { 696 int llchange; 697 698 /* 699 * Check if the link-layer address has changed or not. 700 */ 701 if (!lladdr) 702 llchange = 0; 703 else { 704 if (sdl->sdl_alen) { 705 if (bcmp(lladdr, LLADDR(sdl), ifp->if_addrlen)) 706 llchange = 1; 707 else 708 llchange = 0; 709 } else 710 llchange = 1; 711 } 712 713 /* 714 * This is VERY complex. Look at it with care. 715 * 716 * override solicit lladdr llchange action 717 * (L: record lladdr) 718 * 719 * 0 0 n -- (2c) 720 * 0 0 y n (2b) L 721 * 0 0 y y (1) REACHABLE->STALE 722 * 0 1 n -- (2c) *->REACHABLE 723 * 0 1 y n (2b) L *->REACHABLE 724 * 0 1 y y (1) REACHABLE->STALE 725 * 1 0 n -- (2a) 726 * 1 0 y n (2a) L 727 * 1 0 y y (2a) L *->STALE 728 * 1 1 n -- (2a) *->REACHABLE 729 * 1 1 y n (2a) L *->REACHABLE 730 * 1 1 y y (2a) L *->REACHABLE 731 */ 732 if (!is_override && (lladdr && llchange)) { /* (1) */ 733 /* 734 * If state is REACHABLE, make it STALE. 735 * no other updates should be done. 736 */ 737 if (ln->ln_state == ND6_LLINFO_REACHABLE) { 738 ln->ln_state = ND6_LLINFO_STALE; 739 ln->ln_expire = time_second + nd6_gctimer; 740 } 741 goto freeit; 742 } else if (is_override /* (2a) */ 743 || (!is_override && (lladdr && !llchange)) /* (2b) */ 744 || !lladdr) { /* (2c) */ 745 /* 746 * Update link-local address, if any. 747 */ 748 if (lladdr) { 749 sdl->sdl_alen = ifp->if_addrlen; 750 bcopy(lladdr, LLADDR(sdl), ifp->if_addrlen); 751 } 752 753 /* 754 * If solicited, make the state REACHABLE. 755 * If not solicited and the link-layer address was 756 * changed, make it STALE. 757 */ 758 if (is_solicited) { 759 ln->ln_state = ND6_LLINFO_REACHABLE; 760 ln->ln_byhint = 0; 761 if (ln->ln_expire) { 762 ln->ln_expire = time_second + 763 ND_IFINFO(ifp)->reachable; 764 } 765 } else { 766 if (lladdr && llchange) { 767 ln->ln_state = ND6_LLINFO_STALE; 768 ln->ln_expire = time_second + nd6_gctimer; 769 } 770 } 771 } 772 773 if (ln->ln_router && !is_router) { 774 /* 775 * The peer dropped the router flag. 776 * Remove the sender from the Default Router List and 777 * update the Destination Cache entries. 778 */ 779 struct nd_defrouter *dr; 780 struct in6_addr *in6; 781 int s; 782 783 in6 = &((struct sockaddr_in6 *)rt_key(rt))->sin6_addr; 784 785 /* 786 * Lock to protect the default router list. 787 * XXX: this might be unnecessary, since this function 788 * is only called under the network software interrupt 789 * context. However, we keep it just for safety. 790 */ 791 s = splsoftnet(); 792 dr = defrouter_lookup(in6, rt->rt_ifp); 793 if (dr) 794 defrtrlist_del(dr); 795 else if (!ip6_forwarding && ip6_accept_rtadv) { 796 /* 797 * Even if the neighbor is not in the default 798 * router list, the neighbor may be used 799 * as a next hop for some destinations 800 * (e.g. redirect case). So we must 801 * call rt6_flush explicitly. 802 */ 803 rt6_flush(&ip6->ip6_src, rt->rt_ifp); 804 } 805 splx(s); 806 } 807 ln->ln_router = is_router; 808 } 809 rt->rt_flags &= ~RTF_REJECT; 810 ln->ln_asked = 0; 811 if (ln->ln_hold) { 812 /* 813 * we assume ifp is not a loopback here, so just set the 2nd 814 * argument as the 1st one. 815 */ 816 nd6_output(ifp, ifp, ln->ln_hold, 817 (struct sockaddr_in6 *)rt_key(rt), rt); 818 ln->ln_hold = NULL; 819 } 820 821 freeit: 822 m_freem(m); 823 return; 824 825 bad: 826 icmp6stat.icp6s_badna++; 827 m_freem(m); 828 } 829 830 /* 831 * Neighbor advertisement output handling. 832 * 833 * Based on RFC 2461 834 * 835 * the following items are not implemented yet: 836 * - proxy advertisement delay rule (RFC2461 7.2.8, last paragraph, SHOULD) 837 * - anycast advertisement delay rule (RFC2461 7.2.7, SHOULD) 838 */ 839 void 840 nd6_na_output(ifp, daddr6, taddr6, flags, tlladdr, sdl0) 841 struct ifnet *ifp; 842 const struct in6_addr *daddr6, *taddr6; 843 u_long flags; 844 int tlladdr; /* 1 if include target link-layer address */ 845 struct sockaddr *sdl0; /* sockaddr_dl (= proxy NA) or NULL */ 846 { 847 struct mbuf *m; 848 struct ip6_hdr *ip6; 849 struct nd_neighbor_advert *nd_na; 850 struct ip6_moptions im6o; 851 struct sockaddr_in6 src_sa, dst_sa; 852 struct in6_addr *src0; 853 int icmp6len, maxlen, error; 854 caddr_t mac; 855 struct route_in6 ro; 856 857 mac = NULL; 858 bzero(&ro, sizeof(ro)); 859 860 /* estimate the size of message */ 861 maxlen = sizeof(*ip6) + sizeof(*nd_na); 862 maxlen += (sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7; 863 #ifdef DIAGNOSTIC 864 if (max_linkhdr + maxlen >= MCLBYTES) { 865 printf("nd6_na_output: max_linkhdr + maxlen >= MCLBYTES " 866 "(%d + %d > %d)\n", max_linkhdr, maxlen, MCLBYTES); 867 panic("nd6_na_output: insufficient MCLBYTES"); 868 /* NOTREACHED */ 869 } 870 #endif 871 872 MGETHDR(m, M_DONTWAIT, MT_DATA); 873 if (m && max_linkhdr + maxlen >= MHLEN) { 874 MCLGET(m, M_DONTWAIT); 875 if ((m->m_flags & M_EXT) == 0) { 876 m_free(m); 877 m = NULL; 878 } 879 } 880 if (m == NULL) 881 return; 882 m->m_pkthdr.rcvif = NULL; 883 884 if (IN6_IS_ADDR_MULTICAST(daddr6)) { 885 m->m_flags |= M_MCAST; 886 im6o.im6o_multicast_ifp = ifp; 887 im6o.im6o_multicast_hlim = 255; 888 im6o.im6o_multicast_loop = 0; 889 } 890 891 icmp6len = sizeof(*nd_na); 892 m->m_pkthdr.len = m->m_len = sizeof(struct ip6_hdr) + icmp6len; 893 m->m_data += max_linkhdr; /* or MH_ALIGN() equivalent? */ 894 895 /* fill neighbor advertisement packet */ 896 ip6 = mtod(m, struct ip6_hdr *); 897 ip6->ip6_flow = 0; 898 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 899 ip6->ip6_vfc |= IPV6_VERSION; 900 ip6->ip6_nxt = IPPROTO_ICMPV6; 901 ip6->ip6_hlim = 255; 902 bzero(&src_sa, sizeof(src_sa)); 903 bzero(&dst_sa, sizeof(dst_sa)); 904 src_sa.sin6_len = dst_sa.sin6_len = sizeof(struct sockaddr_in6); 905 src_sa.sin6_family = dst_sa.sin6_family = AF_INET6; 906 dst_sa.sin6_addr = *daddr6; 907 if (IN6_IS_ADDR_UNSPECIFIED(daddr6)) { 908 /* reply to DAD */ 909 dst_sa.sin6_addr.s6_addr16[0] = IPV6_ADDR_INT16_MLL; 910 dst_sa.sin6_addr.s6_addr16[1] = htons(ifp->if_index); 911 dst_sa.sin6_addr.s6_addr32[1] = 0; 912 dst_sa.sin6_addr.s6_addr32[2] = 0; 913 dst_sa.sin6_addr.s6_addr32[3] = IPV6_ADDR_INT32_ONE; 914 915 flags &= ~ND_NA_FLAG_SOLICITED; 916 } 917 ip6->ip6_dst = dst_sa.sin6_addr; 918 919 /* 920 * Select a source whose scope is the same as that of the dest. 921 */ 922 bcopy(&dst_sa, &ro.ro_dst, sizeof(dst_sa)); 923 src0 = in6_selectsrc(&dst_sa, NULL, NULL, &ro, NULL, &error); 924 if (src0 == NULL) { 925 nd6log((LOG_DEBUG, "nd6_na_output: source can't be " 926 "determined: dst=%s, error=%d\n", 927 ip6_sprintf(&dst_sa.sin6_addr), error)); 928 goto bad; 929 } 930 src_sa.sin6_addr = *src0; 931 ip6->ip6_src = src_sa.sin6_addr; 932 nd_na = (struct nd_neighbor_advert *)(ip6 + 1); 933 nd_na->nd_na_type = ND_NEIGHBOR_ADVERT; 934 nd_na->nd_na_code = 0; 935 nd_na->nd_na_target = *taddr6; 936 if (IN6_IS_SCOPE_LINKLOCAL(&nd_na->nd_na_target)) 937 nd_na->nd_na_target.s6_addr16[1] = 0; 938 939 /* 940 * "tlladdr" indicates NS's condition for adding tlladdr or not. 941 * see nd6_ns_input() for details. 942 * Basically, if NS packet is sent to unicast/anycast addr, 943 * target lladdr option SHOULD NOT be included. 944 */ 945 if (tlladdr) { 946 /* 947 * sdl0 != NULL indicates proxy NA. If we do proxy, use 948 * lladdr in sdl0. If we are not proxying (sending NA for 949 * my address) use lladdr configured for the interface. 950 */ 951 if (sdl0 == NULL) 952 mac = nd6_ifptomac(ifp); 953 else if (sdl0->sa_family == AF_LINK) { 954 struct sockaddr_dl *sdl; 955 sdl = (struct sockaddr_dl *)sdl0; 956 if (sdl->sdl_alen == ifp->if_addrlen) 957 mac = LLADDR(sdl); 958 } 959 } 960 if (tlladdr && mac) { 961 int optlen = sizeof(struct nd_opt_hdr) + ifp->if_addrlen; 962 struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)(nd_na + 1); 963 964 /* roundup to 8 bytes alignment! */ 965 optlen = (optlen + 7) & ~7; 966 967 m->m_pkthdr.len += optlen; 968 m->m_len += optlen; 969 icmp6len += optlen; 970 bzero((caddr_t)nd_opt, optlen); 971 nd_opt->nd_opt_type = ND_OPT_TARGET_LINKADDR; 972 nd_opt->nd_opt_len = optlen >> 3; 973 bcopy(mac, (caddr_t)(nd_opt + 1), ifp->if_addrlen); 974 } else 975 flags &= ~ND_NA_FLAG_OVERRIDE; 976 977 ip6->ip6_plen = htons((u_short)icmp6len); 978 nd_na->nd_na_flags_reserved = flags; 979 nd_na->nd_na_cksum = 0; 980 nd_na->nd_na_cksum = 981 in6_cksum(m, IPPROTO_ICMPV6, sizeof(struct ip6_hdr), icmp6len); 982 983 #ifdef IPSEC 984 /* Don't lookup socket */ 985 (void)ipsec_setsocket(m, NULL); 986 #endif 987 ip6_output(m, NULL, NULL, 0, &im6o, NULL); 988 989 icmp6_ifstat_inc(ifp, ifs6_out_msg); 990 icmp6_ifstat_inc(ifp, ifs6_out_neighboradvert); 991 icmp6stat.icp6s_outhist[ND_NEIGHBOR_ADVERT]++; 992 993 if (ro.ro_rt) { /* we don't cache this route. */ 994 RTFREE(ro.ro_rt); 995 } 996 return; 997 998 bad: 999 if (ro.ro_rt) { 1000 RTFREE(ro.ro_rt); 1001 } 1002 m_freem(m); 1003 return; 1004 } 1005 1006 caddr_t 1007 nd6_ifptomac(ifp) 1008 struct ifnet *ifp; 1009 { 1010 switch (ifp->if_type) { 1011 case IFT_ARCNET: 1012 case IFT_ETHER: 1013 case IFT_FDDI: 1014 case IFT_IEEE1394: 1015 case IFT_PROPVIRTUAL: 1016 case IFT_L2VLAN: 1017 case IFT_IEEE80211: 1018 return LLADDR(ifp->if_sadl); 1019 default: 1020 return NULL; 1021 } 1022 } 1023 1024 TAILQ_HEAD(dadq_head, dadq); 1025 struct dadq { 1026 TAILQ_ENTRY(dadq) dad_list; 1027 struct ifaddr *dad_ifa; 1028 int dad_count; /* max NS to send */ 1029 int dad_ns_tcount; /* # of trials to send NS */ 1030 int dad_ns_ocount; /* NS sent so far */ 1031 int dad_ns_icount; 1032 int dad_na_icount; 1033 struct callout dad_timer_ch; 1034 }; 1035 1036 static struct dadq_head dadq; 1037 static int dad_init = 0; 1038 1039 static struct dadq * 1040 nd6_dad_find(ifa) 1041 struct ifaddr *ifa; 1042 { 1043 struct dadq *dp; 1044 1045 for (dp = dadq.tqh_first; dp; dp = dp->dad_list.tqe_next) { 1046 if (dp->dad_ifa == ifa) 1047 return dp; 1048 } 1049 return NULL; 1050 } 1051 1052 static void 1053 nd6_dad_starttimer(dp, ticks) 1054 struct dadq *dp; 1055 int ticks; 1056 { 1057 1058 callout_reset(&dp->dad_timer_ch, ticks, 1059 (void (*) __P((void *)))nd6_dad_timer, (void *)dp->dad_ifa); 1060 } 1061 1062 static void 1063 nd6_dad_stoptimer(dp) 1064 struct dadq *dp; 1065 { 1066 1067 callout_stop(&dp->dad_timer_ch); 1068 } 1069 1070 /* 1071 * Start Duplicated Address Detection (DAD) for specified interface address. 1072 */ 1073 void 1074 nd6_dad_start(ifa, tick) 1075 struct ifaddr *ifa; 1076 int *tick; /* minimum delay ticks for IFF_UP event */ 1077 { 1078 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1079 struct dadq *dp; 1080 1081 if (!dad_init) { 1082 TAILQ_INIT(&dadq); 1083 dad_init++; 1084 } 1085 1086 /* 1087 * If we don't need DAD, don't do it. 1088 * There are several cases: 1089 * - DAD is disabled (ip6_dad_count == 0) 1090 * - the interface address is anycast 1091 */ 1092 if (!(ia->ia6_flags & IN6_IFF_TENTATIVE)) { 1093 log(LOG_DEBUG, 1094 "nd6_dad_start: called with non-tentative address " 1095 "%s(%s)\n", 1096 ip6_sprintf(&ia->ia_addr.sin6_addr), 1097 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1098 return; 1099 } 1100 if (ia->ia6_flags & IN6_IFF_ANYCAST) { 1101 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1102 return; 1103 } 1104 if (!ip6_dad_count) { 1105 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1106 return; 1107 } 1108 if (!ifa->ifa_ifp) 1109 panic("nd6_dad_start: ifa->ifa_ifp == NULL"); 1110 if (!(ifa->ifa_ifp->if_flags & IFF_UP)) 1111 return; 1112 if (nd6_dad_find(ifa) != NULL) { 1113 /* DAD already in progress */ 1114 return; 1115 } 1116 1117 dp = malloc(sizeof(*dp), M_IP6NDP, M_NOWAIT); 1118 if (dp == NULL) { 1119 log(LOG_ERR, "nd6_dad_start: memory allocation failed for " 1120 "%s(%s)\n", 1121 ip6_sprintf(&ia->ia_addr.sin6_addr), 1122 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1123 return; 1124 } 1125 bzero(dp, sizeof(*dp)); 1126 callout_init(&dp->dad_timer_ch); 1127 TAILQ_INSERT_TAIL(&dadq, (struct dadq *)dp, dad_list); 1128 1129 nd6log((LOG_DEBUG, "%s: starting DAD for %s\n", if_name(ifa->ifa_ifp), 1130 ip6_sprintf(&ia->ia_addr.sin6_addr))); 1131 1132 /* 1133 * Send NS packet for DAD, ip6_dad_count times. 1134 * Note that we must delay the first transmission, if this is the 1135 * first packet to be sent from the interface after interface 1136 * (re)initialization. 1137 */ 1138 dp->dad_ifa = ifa; 1139 IFAREF(ifa); /* just for safety */ 1140 dp->dad_count = ip6_dad_count; 1141 dp->dad_ns_icount = dp->dad_na_icount = 0; 1142 dp->dad_ns_ocount = dp->dad_ns_tcount = 0; 1143 if (tick == NULL) { 1144 nd6_dad_ns_output(dp, ifa); 1145 nd6_dad_starttimer(dp, 1146 ND6_RETRANS_SEC(ND_IFINFO(ifa->ifa_ifp)->retrans) * hz); 1147 } else { 1148 int ntick; 1149 1150 if (*tick == 0) 1151 ntick = arc4random() % (MAX_RTR_SOLICITATION_DELAY * hz); 1152 else 1153 ntick = *tick + arc4random() % (hz / 2); 1154 *tick = ntick; 1155 nd6_dad_starttimer(dp, ntick); 1156 } 1157 } 1158 1159 /* 1160 * terminate DAD unconditionally. used for address removals. 1161 */ 1162 void 1163 nd6_dad_stop(ifa) 1164 struct ifaddr *ifa; 1165 { 1166 struct dadq *dp; 1167 1168 if (!dad_init) 1169 return; 1170 dp = nd6_dad_find(ifa); 1171 if (!dp) { 1172 /* DAD wasn't started yet */ 1173 return; 1174 } 1175 1176 nd6_dad_stoptimer(dp); 1177 1178 TAILQ_REMOVE(&dadq, (struct dadq *)dp, dad_list); 1179 free(dp, M_IP6NDP); 1180 dp = NULL; 1181 IFAFREE(ifa); 1182 } 1183 1184 static void 1185 nd6_dad_timer(ifa) 1186 struct ifaddr *ifa; 1187 { 1188 int s; 1189 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1190 struct dadq *dp; 1191 1192 s = splsoftnet(); /* XXX */ 1193 1194 /* Sanity check */ 1195 if (ia == NULL) { 1196 log(LOG_ERR, "nd6_dad_timer: called with null parameter\n"); 1197 goto done; 1198 } 1199 dp = nd6_dad_find(ifa); 1200 if (dp == NULL) { 1201 log(LOG_ERR, "nd6_dad_timer: DAD structure not found\n"); 1202 goto done; 1203 } 1204 if (ia->ia6_flags & IN6_IFF_DUPLICATED) { 1205 log(LOG_ERR, "nd6_dad_timer: called with duplicated address " 1206 "%s(%s)\n", 1207 ip6_sprintf(&ia->ia_addr.sin6_addr), 1208 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1209 goto done; 1210 } 1211 if ((ia->ia6_flags & IN6_IFF_TENTATIVE) == 0) { 1212 log(LOG_ERR, "nd6_dad_timer: called with non-tentative address " 1213 "%s(%s)\n", 1214 ip6_sprintf(&ia->ia_addr.sin6_addr), 1215 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1216 goto done; 1217 } 1218 1219 /* timeouted with IFF_{RUNNING,UP} check */ 1220 if (dp->dad_ns_tcount > dad_maxtry) { 1221 nd6log((LOG_INFO, "%s: could not run DAD, driver problem?\n", 1222 if_name(ifa->ifa_ifp))); 1223 1224 TAILQ_REMOVE(&dadq, (struct dadq *)dp, dad_list); 1225 free(dp, M_IP6NDP); 1226 dp = NULL; 1227 IFAFREE(ifa); 1228 goto done; 1229 } 1230 1231 /* Need more checks? */ 1232 if (dp->dad_ns_ocount < dp->dad_count) { 1233 /* 1234 * We have more NS to go. Send NS packet for DAD. 1235 */ 1236 nd6_dad_ns_output(dp, ifa); 1237 nd6_dad_starttimer(dp, 1238 ND6_RETRANS_SEC(ND_IFINFO(ifa->ifa_ifp)->retrans) * hz); 1239 } else { 1240 /* 1241 * We have transmitted sufficient number of DAD packets. 1242 * See what we've got. 1243 */ 1244 int duplicate; 1245 1246 duplicate = 0; 1247 1248 if (dp->dad_na_icount) { 1249 /* 1250 * the check is in nd6_dad_na_input(), 1251 * but just in case 1252 */ 1253 duplicate++; 1254 } 1255 1256 if (dp->dad_ns_icount) { 1257 #if 0 /* heuristics */ 1258 /* 1259 * if 1260 * - we have sent many(?) DAD NS, and 1261 * - the number of NS we sent equals to the 1262 * number of NS we've got, and 1263 * - we've got no NA 1264 * we may have a faulty network card/driver which 1265 * loops back multicasts to myself. 1266 */ 1267 if (3 < dp->dad_count 1268 && dp->dad_ns_icount == dp->dad_count 1269 && dp->dad_na_icount == 0) { 1270 log(LOG_INFO, "DAD questionable for %s(%s): " 1271 "network card loops back multicast?\n", 1272 ip6_sprintf(&ia->ia_addr.sin6_addr), 1273 if_name(ifa->ifa_ifp)); 1274 /* XXX consider it a duplicate or not? */ 1275 /* duplicate++; */ 1276 } else { 1277 /* We've seen NS, means DAD has failed. */ 1278 duplicate++; 1279 } 1280 #else 1281 /* We've seen NS, means DAD has failed. */ 1282 duplicate++; 1283 #endif 1284 } 1285 1286 if (duplicate) { 1287 /* (*dp) will be freed in nd6_dad_duplicated() */ 1288 dp = NULL; 1289 nd6_dad_duplicated(ifa); 1290 } else { 1291 /* 1292 * We are done with DAD. No NA came, no NS came. 1293 * duplicated address found. 1294 */ 1295 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1296 1297 nd6log((LOG_DEBUG, 1298 "%s: DAD complete for %s - no duplicates found\n", 1299 if_name(ifa->ifa_ifp), 1300 ip6_sprintf(&ia->ia_addr.sin6_addr))); 1301 1302 TAILQ_REMOVE(&dadq, (struct dadq *)dp, dad_list); 1303 free(dp, M_IP6NDP); 1304 dp = NULL; 1305 IFAFREE(ifa); 1306 } 1307 } 1308 1309 done: 1310 splx(s); 1311 } 1312 1313 void 1314 nd6_dad_duplicated(ifa) 1315 struct ifaddr *ifa; 1316 { 1317 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1318 struct dadq *dp; 1319 1320 dp = nd6_dad_find(ifa); 1321 if (dp == NULL) { 1322 log(LOG_ERR, "nd6_dad_duplicated: DAD structure not found\n"); 1323 return; 1324 } 1325 1326 log(LOG_ERR, "%s: DAD detected duplicate IPv6 address %s: " 1327 "NS in/out=%d/%d, NA in=%d\n", 1328 if_name(ifa->ifa_ifp), ip6_sprintf(&ia->ia_addr.sin6_addr), 1329 dp->dad_ns_icount, dp->dad_ns_ocount, dp->dad_na_icount); 1330 1331 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1332 ia->ia6_flags |= IN6_IFF_DUPLICATED; 1333 1334 /* We are done with DAD, with duplicated address found. (failure) */ 1335 nd6_dad_stoptimer(dp); 1336 1337 log(LOG_ERR, "%s: DAD complete for %s - duplicate found\n", 1338 if_name(ifa->ifa_ifp), ip6_sprintf(&ia->ia_addr.sin6_addr)); 1339 log(LOG_ERR, "%s: manual intervention required\n", 1340 if_name(ifa->ifa_ifp)); 1341 1342 TAILQ_REMOVE(&dadq, (struct dadq *)dp, dad_list); 1343 free(dp, M_IP6NDP); 1344 dp = NULL; 1345 IFAFREE(ifa); 1346 } 1347 1348 static void 1349 nd6_dad_ns_output(dp, ifa) 1350 struct dadq *dp; 1351 struct ifaddr *ifa; 1352 { 1353 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1354 struct ifnet *ifp = ifa->ifa_ifp; 1355 1356 dp->dad_ns_tcount++; 1357 if ((ifp->if_flags & IFF_UP) == 0) { 1358 #if 0 1359 printf("%s: interface down?\n", if_name(ifp)); 1360 #endif 1361 return; 1362 } 1363 if ((ifp->if_flags & IFF_RUNNING) == 0) { 1364 #if 0 1365 printf("%s: interface not running?\n", if_name(ifp)); 1366 #endif 1367 return; 1368 } 1369 1370 dp->dad_ns_ocount++; 1371 nd6_ns_output(ifp, NULL, &ia->ia_addr.sin6_addr, NULL, 1); 1372 } 1373 1374 static void 1375 nd6_dad_ns_input(ifa) 1376 struct ifaddr *ifa; 1377 { 1378 struct in6_ifaddr *ia; 1379 struct ifnet *ifp; 1380 const struct in6_addr *taddr6; 1381 struct dadq *dp; 1382 int duplicate; 1383 1384 if (!ifa) 1385 panic("ifa == NULL in nd6_dad_ns_input"); 1386 1387 ia = (struct in6_ifaddr *)ifa; 1388 ifp = ifa->ifa_ifp; 1389 taddr6 = &ia->ia_addr.sin6_addr; 1390 duplicate = 0; 1391 dp = nd6_dad_find(ifa); 1392 1393 /* Quickhack - completely ignore DAD NS packets */ 1394 if (dad_ignore_ns) { 1395 nd6log((LOG_INFO, 1396 "nd6_dad_ns_input: ignoring DAD NS packet for " 1397 "address %s(%s)\n", ip6_sprintf(taddr6), 1398 if_name(ifa->ifa_ifp))); 1399 return; 1400 } 1401 1402 /* 1403 * if I'm yet to start DAD, someone else started using this address 1404 * first. I have a duplicate and you win. 1405 */ 1406 if (!dp || dp->dad_ns_ocount == 0) 1407 duplicate++; 1408 1409 /* XXX more checks for loopback situation - see nd6_dad_timer too */ 1410 1411 if (duplicate) { 1412 dp = NULL; /* will be freed in nd6_dad_duplicated() */ 1413 nd6_dad_duplicated(ifa); 1414 } else { 1415 /* 1416 * not sure if I got a duplicate. 1417 * increment ns count and see what happens. 1418 */ 1419 if (dp) 1420 dp->dad_ns_icount++; 1421 } 1422 } 1423 1424 static void 1425 nd6_dad_na_input(ifa) 1426 struct ifaddr *ifa; 1427 { 1428 struct dadq *dp; 1429 1430 if (!ifa) 1431 panic("ifa == NULL in nd6_dad_na_input"); 1432 1433 dp = nd6_dad_find(ifa); 1434 if (dp) 1435 dp->dad_na_icount++; 1436 1437 /* remove the address. */ 1438 nd6_dad_duplicated(ifa); 1439 } 1440