nd6_nbr.c revision 1.49
1 /* $NetBSD: nd6_nbr.c,v 1.49 2003/08/22 21:53:09 itojun 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 1.49 2003/08/22 21:53:09 itojun 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 IP6_EXTHDR_GET(nd_ns, struct nd_neighbor_solicit *, m, off, icmp6len); 114 if (nd_ns == NULL) { 115 icmp6stat.icp6s_tooshort++; 116 return; 117 } 118 ip6 = mtod(m, struct ip6_hdr *); /* adjust pointer for safety */ 119 taddr6 = nd_ns->nd_ns_target; 120 121 if (ip6->ip6_hlim != 255) { 122 nd6log((LOG_ERR, 123 "nd6_ns_input: invalid hlim (%d) from %s to %s on %s\n", 124 ip6->ip6_hlim, ip6_sprintf(&ip6->ip6_src), 125 ip6_sprintf(&ip6->ip6_dst), if_name(ifp))); 126 goto bad; 127 } 128 129 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) { 130 /* dst has to be solicited node multicast address. */ 131 /* don't check ifindex portion */ 132 if (daddr6.s6_addr16[0] == IPV6_ADDR_INT16_MLL && 133 daddr6.s6_addr32[1] == 0 && 134 daddr6.s6_addr32[2] == IPV6_ADDR_INT32_ONE && 135 daddr6.s6_addr8[12] == 0xff) { 136 ; /* good */ 137 } else { 138 nd6log((LOG_INFO, "nd6_ns_input: bad DAD packet " 139 "(wrong ip6 dst)\n")); 140 goto bad; 141 } 142 } 143 144 if (IN6_IS_ADDR_MULTICAST(&taddr6)) { 145 nd6log((LOG_INFO, "nd6_ns_input: bad NS target (multicast)\n")); 146 goto bad; 147 } 148 149 if (IN6_IS_SCOPE_LINKLOCAL(&taddr6)) 150 taddr6.s6_addr16[1] = htons(ifp->if_index); 151 152 icmp6len -= sizeof(*nd_ns); 153 nd6_option_init(nd_ns + 1, icmp6len, &ndopts); 154 if (nd6_options(&ndopts) < 0) { 155 nd6log((LOG_INFO, 156 "nd6_ns_input: invalid ND option, ignored\n")); 157 /* nd6_options have incremented stats */ 158 goto freeit; 159 } 160 161 if (ndopts.nd_opts_src_lladdr) { 162 lladdr = (char *)(ndopts.nd_opts_src_lladdr + 1); 163 lladdrlen = ndopts.nd_opts_src_lladdr->nd_opt_len << 3; 164 } 165 166 if (IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_src) && lladdr) { 167 nd6log((LOG_INFO, "nd6_ns_input: bad DAD packet " 168 "(link-layer address option)\n")); 169 goto bad; 170 } 171 172 /* 173 * Attaching target link-layer address to the NA? 174 * (RFC 2461 7.2.4) 175 * 176 * NS IP dst is unicast/anycast MUST NOT add 177 * NS IP dst is solicited-node multicast MUST add 178 * 179 * In implementation, we add target link-layer address by default. 180 * We do not add one in MUST NOT cases. 181 */ 182 #if 0 /* too much! */ 183 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &daddr6); 184 if (ifa && (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_ANYCAST)) 185 tlladdr = 0; 186 else 187 #endif 188 if (!IN6_IS_ADDR_MULTICAST(&daddr6)) 189 tlladdr = 0; 190 else 191 tlladdr = 1; 192 193 /* 194 * Target address (taddr6) must be either: 195 * (1) Valid unicast/anycast address for my receiving interface, 196 * (2) Unicast address for which I'm offering proxy service, or 197 * (3) "tentative" address on which DAD is being performed. 198 */ 199 /* (1) and (3) check. */ 200 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &taddr6); 201 202 /* (2) check. */ 203 if (!ifa) { 204 struct rtentry *rt; 205 struct sockaddr_in6 tsin6; 206 207 bzero(&tsin6, sizeof tsin6); 208 tsin6.sin6_len = sizeof(struct sockaddr_in6); 209 tsin6.sin6_family = AF_INET6; 210 tsin6.sin6_addr = taddr6; 211 212 rt = rtalloc1((struct sockaddr *)&tsin6, 0); 213 if (rt && (rt->rt_flags & RTF_ANNOUNCE) != 0 && 214 rt->rt_gateway->sa_family == AF_LINK) { 215 /* 216 * proxy NDP for single entry 217 */ 218 ifa = (struct ifaddr *)in6ifa_ifpforlinklocal(ifp, 219 IN6_IFF_NOTREADY|IN6_IFF_ANYCAST); 220 if (ifa) { 221 proxy = 1; 222 proxydl = SDL(rt->rt_gateway); 223 router = 0; /* XXX */ 224 } 225 } 226 if (rt) 227 rtfree(rt); 228 } 229 if (!ifa) { 230 /* 231 * We've got an NS packet, and we don't have that adddress 232 * assigned for us. We MUST silently ignore it. 233 * See RFC2461 7.2.3. 234 */ 235 goto freeit; 236 } 237 myaddr6 = *IFA_IN6(ifa); 238 anycast = ((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_ANYCAST; 239 tentative = ((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_TENTATIVE; 240 if (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_DUPLICATED) 241 goto freeit; 242 243 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) { 244 nd6log((LOG_INFO, "nd6_ns_input: lladdrlen mismatch for %s " 245 "(if %d, NS packet %d)\n", 246 ip6_sprintf(&taddr6), ifp->if_addrlen, lladdrlen - 2)); 247 goto bad; 248 } 249 250 if (IN6_ARE_ADDR_EQUAL(&myaddr6, &saddr6)) { 251 nd6log((LOG_INFO, "nd6_ns_input: duplicate IP6 address %s\n", 252 ip6_sprintf(&saddr6))); 253 goto freeit; 254 } 255 256 /* 257 * We have neighbor solicitation packet, with target address equals to 258 * one of my tentative address. 259 * 260 * src addr how to process? 261 * --- --- 262 * multicast of course, invalid (rejected in ip6_input) 263 * unicast somebody is doing address resolution -> ignore 264 * unspec dup address detection 265 * 266 * The processing is defined in RFC 2462. 267 */ 268 if (tentative) { 269 /* 270 * If source address is unspecified address, it is for 271 * duplicated address detection. 272 * 273 * If not, the packet is for addess resolution; 274 * silently ignore it. 275 */ 276 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) 277 nd6_dad_ns_input(ifa); 278 279 goto freeit; 280 } 281 282 /* 283 * If the source address is unspecified address, entries must not 284 * be created or updated. 285 * It looks that sender is performing DAD. Output NA toward 286 * all-node multicast address, to tell the sender that I'm using 287 * the address. 288 * S bit ("solicited") must be zero. 289 */ 290 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) { 291 saddr6 = in6addr_linklocal_allnodes; 292 saddr6.s6_addr16[1] = htons(ifp->if_index); 293 nd6_na_output(ifp, &saddr6, &taddr6, 294 ((anycast || proxy || !tlladdr) ? 0 : ND_NA_FLAG_OVERRIDE) | 295 (router ? ND_NA_FLAG_ROUTER : 0), 296 tlladdr, (struct sockaddr *)proxydl); 297 goto freeit; 298 } 299 300 nd6_cache_lladdr(ifp, &saddr6, lladdr, lladdrlen, ND_NEIGHBOR_SOLICIT, 0); 301 302 nd6_na_output(ifp, &saddr6, &taddr6, 303 ((anycast || proxy || !tlladdr) ? 0 : ND_NA_FLAG_OVERRIDE) | 304 (router ? ND_NA_FLAG_ROUTER : 0) | ND_NA_FLAG_SOLICITED, 305 tlladdr, (struct sockaddr *)proxydl); 306 freeit: 307 m_freem(m); 308 return; 309 310 bad: 311 nd6log((LOG_ERR, "nd6_ns_input: src=%s\n", ip6_sprintf(&saddr6))); 312 nd6log((LOG_ERR, "nd6_ns_input: dst=%s\n", ip6_sprintf(&daddr6))); 313 nd6log((LOG_ERR, "nd6_ns_input: tgt=%s\n", ip6_sprintf(&taddr6))); 314 icmp6stat.icp6s_badns++; 315 m_freem(m); 316 } 317 318 /* 319 * Output an Neighbor Solicitation Message. Caller specifies: 320 * - ICMP6 header source IP6 address 321 * - ND6 header target IP6 address 322 * - ND6 header source datalink address 323 * 324 * Based on RFC 2461 325 * Based on RFC 2462 (duplicated address detection) 326 */ 327 void 328 nd6_ns_output(ifp, daddr6, taddr6, ln, dad) 329 struct ifnet *ifp; 330 const struct in6_addr *daddr6, *taddr6; 331 struct llinfo_nd6 *ln; /* for source address determination */ 332 int dad; /* duplicated address detection */ 333 { 334 struct mbuf *m; 335 struct ip6_hdr *ip6; 336 struct nd_neighbor_solicit *nd_ns; 337 struct sockaddr_in6 src_sa, dst_sa; 338 struct ip6_moptions im6o; 339 int icmp6len; 340 int maxlen; 341 caddr_t mac; 342 struct route_in6 ro; 343 344 bzero(&ro, sizeof(ro)); 345 346 if (IN6_IS_ADDR_MULTICAST(taddr6)) 347 return; 348 349 /* estimate the size of message */ 350 maxlen = sizeof(*ip6) + sizeof(*nd_ns); 351 maxlen += (sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7; 352 #ifdef DIAGNOSTIC 353 if (max_linkhdr + maxlen >= MCLBYTES) { 354 printf("nd6_ns_output: max_linkhdr + maxlen >= MCLBYTES " 355 "(%d + %d > %d)\n", max_linkhdr, maxlen, MCLBYTES); 356 panic("nd6_ns_output: insufficient MCLBYTES"); 357 /* NOTREACHED */ 358 } 359 #endif 360 361 MGETHDR(m, M_DONTWAIT, MT_DATA); 362 if (m && max_linkhdr + maxlen >= MHLEN) { 363 MCLGET(m, M_DONTWAIT); 364 if ((m->m_flags & M_EXT) == 0) { 365 m_free(m); 366 m = NULL; 367 } 368 } 369 if (m == NULL) 370 return; 371 m->m_pkthdr.rcvif = NULL; 372 373 if (daddr6 == NULL || IN6_IS_ADDR_MULTICAST(daddr6)) { 374 m->m_flags |= M_MCAST; 375 im6o.im6o_multicast_ifp = ifp; 376 im6o.im6o_multicast_hlim = 255; 377 im6o.im6o_multicast_loop = 0; 378 } 379 380 icmp6len = sizeof(*nd_ns); 381 m->m_pkthdr.len = m->m_len = sizeof(*ip6) + icmp6len; 382 m->m_data += max_linkhdr; /* or MH_ALIGN() equivalent? */ 383 384 /* fill neighbor solicitation packet */ 385 ip6 = mtod(m, struct ip6_hdr *); 386 ip6->ip6_flow = 0; 387 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 388 ip6->ip6_vfc |= IPV6_VERSION; 389 /* ip6->ip6_plen will be set later */ 390 ip6->ip6_nxt = IPPROTO_ICMPV6; 391 ip6->ip6_hlim = 255; 392 /* determine the source and destination addresses */ 393 bzero(&src_sa, sizeof(src_sa)); 394 bzero(&dst_sa, sizeof(dst_sa)); 395 src_sa.sin6_family = dst_sa.sin6_family = AF_INET6; 396 src_sa.sin6_len = dst_sa.sin6_len = sizeof(struct sockaddr_in6); 397 if (daddr6) 398 dst_sa.sin6_addr = *daddr6; 399 else { 400 dst_sa.sin6_addr.s6_addr16[0] = IPV6_ADDR_INT16_MLL; 401 dst_sa.sin6_addr.s6_addr16[1] = htons(ifp->if_index); 402 dst_sa.sin6_addr.s6_addr32[1] = 0; 403 dst_sa.sin6_addr.s6_addr32[2] = IPV6_ADDR_INT32_ONE; 404 dst_sa.sin6_addr.s6_addr32[3] = taddr6->s6_addr32[3]; 405 dst_sa.sin6_addr.s6_addr8[12] = 0xff; 406 } 407 ip6->ip6_dst = dst_sa.sin6_addr; 408 if (!dad) { 409 /* 410 * RFC2461 7.2.2: 411 * "If the source address of the packet prompting the 412 * solicitation is the same as one of the addresses assigned 413 * to the outgoing interface, that address SHOULD be placed 414 * in the IP Source Address of the outgoing solicitation. 415 * Otherwise, any one of the addresses assigned to the 416 * interface should be used." 417 * 418 * We use the source address for the prompting packet 419 * (saddr6), if: 420 * - saddr6 is given from the caller (by giving "ln"), and 421 * - saddr6 belongs to the outgoing interface. 422 * Otherwise, we perform the source address selection as usual. 423 */ 424 struct ip6_hdr *hip6; /* hold ip6 */ 425 struct in6_addr *saddr6; 426 427 if (ln && ln->ln_hold) { 428 hip6 = mtod(ln->ln_hold, struct ip6_hdr *); 429 /* XXX pullup? */ 430 if (sizeof(*hip6) < ln->ln_hold->m_len) 431 saddr6 = &hip6->ip6_src; 432 else 433 saddr6 = NULL; 434 } else 435 saddr6 = NULL; 436 if (saddr6 && in6ifa_ifpwithaddr(ifp, saddr6)) 437 src_sa.sin6_addr = *saddr6; 438 else { 439 struct in6_addr *src0; 440 int error; 441 442 bcopy(&dst_sa, &ro.ro_dst, sizeof(dst_sa)); 443 src0 = in6_selectsrc(&dst_sa, NULL, NULL, &ro, NULL, 444 &error); 445 if (src0 == NULL) { 446 nd6log((LOG_DEBUG, 447 "nd6_ns_output: source can't be " 448 "determined: dst=%s, error=%d\n", 449 ip6_sprintf(&dst_sa.sin6_addr), error)); 450 goto bad; 451 } 452 src_sa.sin6_addr = *src0; 453 } 454 } else { 455 /* 456 * Source address for DAD packet must always be IPv6 457 * unspecified address. (0::0) 458 * We actually don't have to 0-clear the address (we did it 459 * above), but we do so here explicitly to make the intention 460 * clearer. 461 */ 462 bzero(&src_sa.sin6_addr, sizeof(src_sa.sin6_addr)); 463 } 464 ip6->ip6_src = src_sa.sin6_addr; 465 nd_ns = (struct nd_neighbor_solicit *)(ip6 + 1); 466 nd_ns->nd_ns_type = ND_NEIGHBOR_SOLICIT; 467 nd_ns->nd_ns_code = 0; 468 nd_ns->nd_ns_reserved = 0; 469 nd_ns->nd_ns_target = *taddr6; 470 471 if (IN6_IS_SCOPE_LINKLOCAL(&nd_ns->nd_ns_target)) 472 nd_ns->nd_ns_target.s6_addr16[1] = 0; 473 474 /* 475 * Add source link-layer address option. 476 * 477 * spec implementation 478 * --- --- 479 * DAD packet MUST NOT do not add the option 480 * there's no link layer address: 481 * impossible do not add the option 482 * there's link layer address: 483 * Multicast NS MUST add one add the option 484 * Unicast NS SHOULD add one add the option 485 */ 486 if (!dad && (mac = nd6_ifptomac(ifp))) { 487 int optlen = sizeof(struct nd_opt_hdr) + ifp->if_addrlen; 488 struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)(nd_ns + 1); 489 /* 8 byte alignments... */ 490 optlen = (optlen + 7) & ~7; 491 492 m->m_pkthdr.len += optlen; 493 m->m_len += optlen; 494 icmp6len += optlen; 495 bzero((caddr_t)nd_opt, optlen); 496 nd_opt->nd_opt_type = ND_OPT_SOURCE_LINKADDR; 497 nd_opt->nd_opt_len = optlen >> 3; 498 bcopy(mac, (caddr_t)(nd_opt + 1), ifp->if_addrlen); 499 } 500 501 ip6->ip6_plen = htons((u_short)icmp6len); 502 nd_ns->nd_ns_cksum = 0; 503 nd_ns->nd_ns_cksum = 504 in6_cksum(m, IPPROTO_ICMPV6, sizeof(*ip6), icmp6len); 505 506 #ifdef IPSEC 507 /* Don't lookup socket */ 508 (void)ipsec_setsocket(m, NULL); 509 #endif 510 ip6_output(m, NULL, &ro, dad ? IPV6_UNSPECSRC : 0, 511 &im6o, (struct socket *)NULL, NULL); 512 icmp6_ifstat_inc(ifp, ifs6_out_msg); 513 icmp6_ifstat_inc(ifp, ifs6_out_neighborsolicit); 514 icmp6stat.icp6s_outhist[ND_NEIGHBOR_SOLICIT]++; 515 516 if (ro.ro_rt) { /* we don't cache this route. */ 517 RTFREE(ro.ro_rt); 518 } 519 return; 520 521 bad: 522 if (ro.ro_rt) { 523 RTFREE(ro.ro_rt); 524 } 525 m_freem(m); 526 return; 527 } 528 529 /* 530 * Neighbor advertisement input handling. 531 * 532 * Based on RFC 2461 533 * Based on RFC 2462 (duplicated address detection) 534 * 535 * the following items are not implemented yet: 536 * - proxy advertisement delay rule (RFC2461 7.2.8, last paragraph, SHOULD) 537 * - anycast advertisement delay rule (RFC2461 7.2.7, SHOULD) 538 */ 539 void 540 nd6_na_input(m, off, icmp6len) 541 struct mbuf *m; 542 int off, icmp6len; 543 { 544 struct ifnet *ifp = m->m_pkthdr.rcvif; 545 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 546 struct nd_neighbor_advert *nd_na; 547 #if 0 548 struct in6_addr saddr6 = ip6->ip6_src; 549 #endif 550 struct in6_addr daddr6 = ip6->ip6_dst; 551 struct in6_addr taddr6; 552 int flags; 553 int is_router; 554 int is_solicited; 555 int is_override; 556 char *lladdr = NULL; 557 int lladdrlen = 0; 558 struct ifaddr *ifa; 559 struct llinfo_nd6 *ln; 560 struct rtentry *rt; 561 struct sockaddr_dl *sdl; 562 union nd_opts ndopts; 563 564 if (ip6->ip6_hlim != 255) { 565 nd6log((LOG_ERR, 566 "nd6_na_input: invalid hlim (%d) from %s to %s on %s\n", 567 ip6->ip6_hlim, ip6_sprintf(&ip6->ip6_src), 568 ip6_sprintf(&ip6->ip6_dst), if_name(ifp))); 569 goto bad; 570 } 571 572 IP6_EXTHDR_GET(nd_na, struct nd_neighbor_advert *, m, off, icmp6len); 573 if (nd_na == NULL) { 574 icmp6stat.icp6s_tooshort++; 575 return; 576 } 577 taddr6 = nd_na->nd_na_target; 578 flags = nd_na->nd_na_flags_reserved; 579 is_router = ((flags & ND_NA_FLAG_ROUTER) != 0); 580 is_solicited = ((flags & ND_NA_FLAG_SOLICITED) != 0); 581 is_override = ((flags & ND_NA_FLAG_OVERRIDE) != 0); 582 583 if (IN6_IS_SCOPE_LINKLOCAL(&taddr6)) 584 taddr6.s6_addr16[1] = htons(ifp->if_index); 585 586 if (IN6_IS_ADDR_MULTICAST(&taddr6)) { 587 nd6log((LOG_ERR, 588 "nd6_na_input: invalid target address %s\n", 589 ip6_sprintf(&taddr6))); 590 goto bad; 591 } 592 if (is_solicited && IN6_IS_ADDR_MULTICAST(&daddr6)) { 593 nd6log((LOG_ERR, 594 "nd6_na_input: a solicited adv is multicasted\n")); 595 goto bad; 596 } 597 598 icmp6len -= sizeof(*nd_na); 599 nd6_option_init(nd_na + 1, icmp6len, &ndopts); 600 if (nd6_options(&ndopts) < 0) { 601 nd6log((LOG_INFO, 602 "nd6_na_input: invalid ND option, ignored\n")); 603 /* nd6_options have incremented stats */ 604 goto freeit; 605 } 606 607 if (ndopts.nd_opts_tgt_lladdr) { 608 lladdr = (char *)(ndopts.nd_opts_tgt_lladdr + 1); 609 lladdrlen = ndopts.nd_opts_tgt_lladdr->nd_opt_len << 3; 610 } 611 612 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &taddr6); 613 614 /* 615 * Target address matches one of my interface address. 616 * 617 * If my address is tentative, this means that there's somebody 618 * already using the same address as mine. This indicates DAD failure. 619 * This is defined in RFC 2462. 620 * 621 * Otherwise, process as defined in RFC 2461. 622 */ 623 if (ifa 624 && (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_TENTATIVE)) { 625 nd6_dad_na_input(ifa); 626 goto freeit; 627 } 628 629 /* Just for safety, maybe unnecessary. */ 630 if (ifa) { 631 log(LOG_ERR, 632 "nd6_na_input: duplicate IP6 address %s\n", 633 ip6_sprintf(&taddr6)); 634 goto freeit; 635 } 636 637 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) { 638 nd6log((LOG_INFO, "nd6_na_input: lladdrlen mismatch for %s " 639 "(if %d, NA packet %d)\n", ip6_sprintf(&taddr6), 640 ifp->if_addrlen, lladdrlen - 2)); 641 goto bad; 642 } 643 644 /* 645 * If no neighbor cache entry is found, NA SHOULD silently be 646 * discarded. 647 */ 648 rt = nd6_lookup(&taddr6, 0, ifp); 649 if ((rt == NULL) || 650 ((ln = (struct llinfo_nd6 *)rt->rt_llinfo) == NULL) || 651 ((sdl = SDL(rt->rt_gateway)) == NULL)) 652 goto freeit; 653 654 if (ln->ln_state == ND6_LLINFO_INCOMPLETE) { 655 /* 656 * If the link-layer has address, and no lladdr option came, 657 * discard the packet. 658 */ 659 if (ifp->if_addrlen && !lladdr) 660 goto freeit; 661 662 /* 663 * Record link-layer address, and update the state. 664 */ 665 sdl->sdl_alen = ifp->if_addrlen; 666 bcopy(lladdr, LLADDR(sdl), ifp->if_addrlen); 667 if (is_solicited) { 668 ln->ln_state = ND6_LLINFO_REACHABLE; 669 ln->ln_byhint = 0; 670 if (!ND6_LLINFO_PERMANENT(ln)) { 671 nd6_llinfo_settimer(ln, 672 (long)ND_IFINFO(rt->rt_ifp)->reachable * hz); 673 } 674 } else { 675 ln->ln_state = ND6_LLINFO_STALE; 676 nd6_llinfo_settimer(ln, (long)nd6_gctimer * hz); 677 } 678 if ((ln->ln_router = is_router) != 0) { 679 /* 680 * This means a router's state has changed from 681 * non-reachable to probably reachable, and might 682 * affect the status of associated prefixes.. 683 */ 684 pfxlist_onlink_check(); 685 } 686 } else { 687 int llchange; 688 689 /* 690 * Check if the link-layer address has changed or not. 691 */ 692 if (!lladdr) 693 llchange = 0; 694 else { 695 if (sdl->sdl_alen) { 696 if (bcmp(lladdr, LLADDR(sdl), ifp->if_addrlen)) 697 llchange = 1; 698 else 699 llchange = 0; 700 } else 701 llchange = 1; 702 } 703 704 /* 705 * This is VERY complex. Look at it with care. 706 * 707 * override solicit lladdr llchange action 708 * (L: record lladdr) 709 * 710 * 0 0 n -- (2c) 711 * 0 0 y n (2b) L 712 * 0 0 y y (1) REACHABLE->STALE 713 * 0 1 n -- (2c) *->REACHABLE 714 * 0 1 y n (2b) L *->REACHABLE 715 * 0 1 y y (1) REACHABLE->STALE 716 * 1 0 n -- (2a) 717 * 1 0 y n (2a) L 718 * 1 0 y y (2a) L *->STALE 719 * 1 1 n -- (2a) *->REACHABLE 720 * 1 1 y n (2a) L *->REACHABLE 721 * 1 1 y y (2a) L *->REACHABLE 722 */ 723 if (!is_override && (lladdr && llchange)) { /* (1) */ 724 /* 725 * If state is REACHABLE, make it STALE. 726 * no other updates should be done. 727 */ 728 if (ln->ln_state == ND6_LLINFO_REACHABLE) { 729 ln->ln_state = ND6_LLINFO_STALE; 730 nd6_llinfo_settimer(ln, (long)nd6_gctimer * hz); 731 } 732 goto freeit; 733 } else if (is_override /* (2a) */ 734 || (!is_override && (lladdr && !llchange)) /* (2b) */ 735 || !lladdr) { /* (2c) */ 736 /* 737 * Update link-local address, if any. 738 */ 739 if (lladdr) { 740 sdl->sdl_alen = ifp->if_addrlen; 741 bcopy(lladdr, LLADDR(sdl), ifp->if_addrlen); 742 } 743 744 /* 745 * If solicited, make the state REACHABLE. 746 * If not solicited and the link-layer address was 747 * changed, make it STALE. 748 */ 749 if (is_solicited) { 750 ln->ln_state = ND6_LLINFO_REACHABLE; 751 ln->ln_byhint = 0; 752 if (!ND6_LLINFO_PERMANENT(ln)) { 753 nd6_llinfo_settimer(ln, 754 (long)ND_IFINFO(ifp)->reachable * hz); 755 } 756 } else { 757 if (lladdr && llchange) { 758 ln->ln_state = ND6_LLINFO_STALE; 759 nd6_llinfo_settimer(ln, 760 (long)nd6_gctimer * hz); 761 } 762 } 763 } 764 765 if (ln->ln_router && !is_router) { 766 /* 767 * The peer dropped the router flag. 768 * Remove the sender from the Default Router List and 769 * update the Destination Cache entries. 770 */ 771 struct nd_defrouter *dr; 772 struct in6_addr *in6; 773 int s; 774 775 in6 = &((struct sockaddr_in6 *)rt_key(rt))->sin6_addr; 776 777 /* 778 * Lock to protect the default router list. 779 * XXX: this might be unnecessary, since this function 780 * is only called under the network software interrupt 781 * context. However, we keep it just for safety. 782 */ 783 s = splsoftnet(); 784 dr = defrouter_lookup(in6, rt->rt_ifp); 785 if (dr) 786 defrtrlist_del(dr); 787 else if (!ip6_forwarding) { 788 /* 789 * Even if the neighbor is not in the default 790 * router list, the neighbor may be used 791 * as a next hop for some destinations 792 * (e.g. redirect case). So we must 793 * call rt6_flush explicitly. 794 */ 795 rt6_flush(&ip6->ip6_src, rt->rt_ifp); 796 } 797 splx(s); 798 } 799 ln->ln_router = is_router; 800 } 801 rt->rt_flags &= ~RTF_REJECT; 802 ln->ln_asked = 0; 803 if (ln->ln_hold) { 804 /* 805 * we assume ifp is not a loopback here, so just set the 2nd 806 * argument as the 1st one. 807 */ 808 nd6_output(ifp, ifp, ln->ln_hold, 809 (struct sockaddr_in6 *)rt_key(rt), rt); 810 ln->ln_hold = NULL; 811 } 812 813 freeit: 814 m_freem(m); 815 return; 816 817 bad: 818 icmp6stat.icp6s_badna++; 819 m_freem(m); 820 } 821 822 /* 823 * Neighbor advertisement output handling. 824 * 825 * Based on RFC 2461 826 * 827 * the following items are not implemented yet: 828 * - proxy advertisement delay rule (RFC2461 7.2.8, last paragraph, SHOULD) 829 * - anycast advertisement delay rule (RFC2461 7.2.7, SHOULD) 830 */ 831 void 832 nd6_na_output(ifp, daddr6, taddr6, flags, tlladdr, sdl0) 833 struct ifnet *ifp; 834 const struct in6_addr *daddr6, *taddr6; 835 u_long flags; 836 int tlladdr; /* 1 if include target link-layer address */ 837 struct sockaddr *sdl0; /* sockaddr_dl (= proxy NA) or NULL */ 838 { 839 struct mbuf *m; 840 struct ip6_hdr *ip6; 841 struct nd_neighbor_advert *nd_na; 842 struct ip6_moptions im6o; 843 struct sockaddr_in6 src_sa, dst_sa; 844 struct in6_addr *src0; 845 int icmp6len, maxlen, error; 846 caddr_t mac; 847 struct route_in6 ro; 848 849 mac = NULL; 850 bzero(&ro, sizeof(ro)); 851 852 /* estimate the size of message */ 853 maxlen = sizeof(*ip6) + sizeof(*nd_na); 854 maxlen += (sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7; 855 #ifdef DIAGNOSTIC 856 if (max_linkhdr + maxlen >= MCLBYTES) { 857 printf("nd6_na_output: max_linkhdr + maxlen >= MCLBYTES " 858 "(%d + %d > %d)\n", max_linkhdr, maxlen, MCLBYTES); 859 panic("nd6_na_output: insufficient MCLBYTES"); 860 /* NOTREACHED */ 861 } 862 #endif 863 864 MGETHDR(m, M_DONTWAIT, MT_DATA); 865 if (m && max_linkhdr + maxlen >= MHLEN) { 866 MCLGET(m, M_DONTWAIT); 867 if ((m->m_flags & M_EXT) == 0) { 868 m_free(m); 869 m = NULL; 870 } 871 } 872 if (m == NULL) 873 return; 874 m->m_pkthdr.rcvif = NULL; 875 876 if (IN6_IS_ADDR_MULTICAST(daddr6)) { 877 m->m_flags |= M_MCAST; 878 im6o.im6o_multicast_ifp = ifp; 879 im6o.im6o_multicast_hlim = 255; 880 im6o.im6o_multicast_loop = 0; 881 } 882 883 icmp6len = sizeof(*nd_na); 884 m->m_pkthdr.len = m->m_len = sizeof(struct ip6_hdr) + icmp6len; 885 m->m_data += max_linkhdr; /* or MH_ALIGN() equivalent? */ 886 887 /* fill neighbor advertisement packet */ 888 ip6 = mtod(m, struct ip6_hdr *); 889 ip6->ip6_flow = 0; 890 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 891 ip6->ip6_vfc |= IPV6_VERSION; 892 ip6->ip6_nxt = IPPROTO_ICMPV6; 893 ip6->ip6_hlim = 255; 894 bzero(&src_sa, sizeof(src_sa)); 895 bzero(&dst_sa, sizeof(dst_sa)); 896 src_sa.sin6_len = dst_sa.sin6_len = sizeof(struct sockaddr_in6); 897 src_sa.sin6_family = dst_sa.sin6_family = AF_INET6; 898 dst_sa.sin6_addr = *daddr6; 899 if (IN6_IS_ADDR_UNSPECIFIED(daddr6)) { 900 /* reply to DAD */ 901 dst_sa.sin6_addr.s6_addr16[0] = IPV6_ADDR_INT16_MLL; 902 dst_sa.sin6_addr.s6_addr16[1] = htons(ifp->if_index); 903 dst_sa.sin6_addr.s6_addr32[1] = 0; 904 dst_sa.sin6_addr.s6_addr32[2] = 0; 905 dst_sa.sin6_addr.s6_addr32[3] = IPV6_ADDR_INT32_ONE; 906 907 flags &= ~ND_NA_FLAG_SOLICITED; 908 } 909 ip6->ip6_dst = dst_sa.sin6_addr; 910 911 /* 912 * Select a source whose scope is the same as that of the dest. 913 */ 914 bcopy(&dst_sa, &ro.ro_dst, sizeof(dst_sa)); 915 src0 = in6_selectsrc(&dst_sa, NULL, NULL, &ro, NULL, &error); 916 if (src0 == NULL) { 917 nd6log((LOG_DEBUG, "nd6_na_output: source can't be " 918 "determined: dst=%s, error=%d\n", 919 ip6_sprintf(&dst_sa.sin6_addr), error)); 920 goto bad; 921 } 922 src_sa.sin6_addr = *src0; 923 ip6->ip6_src = src_sa.sin6_addr; 924 nd_na = (struct nd_neighbor_advert *)(ip6 + 1); 925 nd_na->nd_na_type = ND_NEIGHBOR_ADVERT; 926 nd_na->nd_na_code = 0; 927 nd_na->nd_na_target = *taddr6; 928 if (IN6_IS_SCOPE_LINKLOCAL(&nd_na->nd_na_target)) 929 nd_na->nd_na_target.s6_addr16[1] = 0; 930 931 /* 932 * "tlladdr" indicates NS's condition for adding tlladdr or not. 933 * see nd6_ns_input() for details. 934 * Basically, if NS packet is sent to unicast/anycast addr, 935 * target lladdr option SHOULD NOT be included. 936 */ 937 if (tlladdr) { 938 /* 939 * sdl0 != NULL indicates proxy NA. If we do proxy, use 940 * lladdr in sdl0. If we are not proxying (sending NA for 941 * my address) use lladdr configured for the interface. 942 */ 943 if (sdl0 == NULL) 944 mac = nd6_ifptomac(ifp); 945 else if (sdl0->sa_family == AF_LINK) { 946 struct sockaddr_dl *sdl; 947 sdl = (struct sockaddr_dl *)sdl0; 948 if (sdl->sdl_alen == ifp->if_addrlen) 949 mac = LLADDR(sdl); 950 } 951 } 952 if (tlladdr && mac) { 953 int optlen = sizeof(struct nd_opt_hdr) + ifp->if_addrlen; 954 struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)(nd_na + 1); 955 956 /* roundup to 8 bytes alignment! */ 957 optlen = (optlen + 7) & ~7; 958 959 m->m_pkthdr.len += optlen; 960 m->m_len += optlen; 961 icmp6len += optlen; 962 bzero((caddr_t)nd_opt, optlen); 963 nd_opt->nd_opt_type = ND_OPT_TARGET_LINKADDR; 964 nd_opt->nd_opt_len = optlen >> 3; 965 bcopy(mac, (caddr_t)(nd_opt + 1), ifp->if_addrlen); 966 } else 967 flags &= ~ND_NA_FLAG_OVERRIDE; 968 969 ip6->ip6_plen = htons((u_short)icmp6len); 970 nd_na->nd_na_flags_reserved = flags; 971 nd_na->nd_na_cksum = 0; 972 nd_na->nd_na_cksum = 973 in6_cksum(m, IPPROTO_ICMPV6, sizeof(struct ip6_hdr), icmp6len); 974 975 #ifdef IPSEC 976 /* Don't lookup socket */ 977 (void)ipsec_setsocket(m, NULL); 978 #endif 979 ip6_output(m, NULL, NULL, 0, &im6o, (struct socket *)NULL, NULL); 980 981 icmp6_ifstat_inc(ifp, ifs6_out_msg); 982 icmp6_ifstat_inc(ifp, ifs6_out_neighboradvert); 983 icmp6stat.icp6s_outhist[ND_NEIGHBOR_ADVERT]++; 984 985 if (ro.ro_rt) { /* we don't cache this route. */ 986 RTFREE(ro.ro_rt); 987 } 988 return; 989 990 bad: 991 if (ro.ro_rt) { 992 RTFREE(ro.ro_rt); 993 } 994 m_freem(m); 995 return; 996 } 997 998 caddr_t 999 nd6_ifptomac(ifp) 1000 struct ifnet *ifp; 1001 { 1002 switch (ifp->if_type) { 1003 case IFT_ARCNET: 1004 case IFT_ETHER: 1005 case IFT_FDDI: 1006 case IFT_IEEE1394: 1007 case IFT_PROPVIRTUAL: 1008 case IFT_L2VLAN: 1009 case IFT_IEEE80211: 1010 return LLADDR(ifp->if_sadl); 1011 default: 1012 return NULL; 1013 } 1014 } 1015 1016 TAILQ_HEAD(dadq_head, dadq); 1017 struct dadq { 1018 TAILQ_ENTRY(dadq) dad_list; 1019 struct ifaddr *dad_ifa; 1020 int dad_count; /* max NS to send */ 1021 int dad_ns_tcount; /* # of trials to send NS */ 1022 int dad_ns_ocount; /* NS sent so far */ 1023 int dad_ns_icount; 1024 int dad_na_icount; 1025 struct callout dad_timer_ch; 1026 }; 1027 1028 static struct dadq_head dadq; 1029 static int dad_init = 0; 1030 1031 static struct dadq * 1032 nd6_dad_find(ifa) 1033 struct ifaddr *ifa; 1034 { 1035 struct dadq *dp; 1036 1037 for (dp = dadq.tqh_first; dp; dp = dp->dad_list.tqe_next) { 1038 if (dp->dad_ifa == ifa) 1039 return dp; 1040 } 1041 return NULL; 1042 } 1043 1044 static void 1045 nd6_dad_starttimer(dp, ticks) 1046 struct dadq *dp; 1047 int ticks; 1048 { 1049 1050 callout_reset(&dp->dad_timer_ch, ticks, 1051 (void (*) __P((void *)))nd6_dad_timer, (void *)dp->dad_ifa); 1052 } 1053 1054 static void 1055 nd6_dad_stoptimer(dp) 1056 struct dadq *dp; 1057 { 1058 1059 callout_stop(&dp->dad_timer_ch); 1060 } 1061 1062 /* 1063 * Start Duplicated Address Detection (DAD) for specified interface address. 1064 */ 1065 void 1066 nd6_dad_start(ifa, tick) 1067 struct ifaddr *ifa; 1068 int *tick; /* minimum delay ticks for IFF_UP event */ 1069 { 1070 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1071 struct dadq *dp; 1072 1073 if (!dad_init) { 1074 TAILQ_INIT(&dadq); 1075 dad_init++; 1076 } 1077 1078 /* 1079 * If we don't need DAD, don't do it. 1080 * There are several cases: 1081 * - DAD is disabled (ip6_dad_count == 0) 1082 * - the interface address is anycast 1083 */ 1084 if (!(ia->ia6_flags & IN6_IFF_TENTATIVE)) { 1085 log(LOG_DEBUG, 1086 "nd6_dad_start: called with non-tentative address " 1087 "%s(%s)\n", 1088 ip6_sprintf(&ia->ia_addr.sin6_addr), 1089 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1090 return; 1091 } 1092 if (ia->ia6_flags & IN6_IFF_ANYCAST) { 1093 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1094 return; 1095 } 1096 if (!ip6_dad_count) { 1097 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1098 return; 1099 } 1100 if (!ifa->ifa_ifp) 1101 panic("nd6_dad_start: ifa->ifa_ifp == NULL"); 1102 if (!(ifa->ifa_ifp->if_flags & IFF_UP)) 1103 return; 1104 if (nd6_dad_find(ifa) != NULL) { 1105 /* DAD already in progress */ 1106 return; 1107 } 1108 1109 dp = malloc(sizeof(*dp), M_IP6NDP, M_NOWAIT); 1110 if (dp == NULL) { 1111 log(LOG_ERR, "nd6_dad_start: memory allocation failed for " 1112 "%s(%s)\n", 1113 ip6_sprintf(&ia->ia_addr.sin6_addr), 1114 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1115 return; 1116 } 1117 bzero(dp, sizeof(*dp)); 1118 callout_init(&dp->dad_timer_ch); 1119 TAILQ_INSERT_TAIL(&dadq, (struct dadq *)dp, dad_list); 1120 1121 nd6log((LOG_DEBUG, "%s: starting DAD for %s\n", if_name(ifa->ifa_ifp), 1122 ip6_sprintf(&ia->ia_addr.sin6_addr))); 1123 1124 /* 1125 * Send NS packet for DAD, ip6_dad_count times. 1126 * Note that we must delay the first transmission, if this is the 1127 * first packet to be sent from the interface after interface 1128 * (re)initialization. 1129 */ 1130 dp->dad_ifa = ifa; 1131 IFAREF(ifa); /* just for safety */ 1132 dp->dad_count = ip6_dad_count; 1133 dp->dad_ns_icount = dp->dad_na_icount = 0; 1134 dp->dad_ns_ocount = dp->dad_ns_tcount = 0; 1135 if (tick == NULL) { 1136 nd6_dad_ns_output(dp, ifa); 1137 nd6_dad_starttimer(dp, 1138 (long)ND_IFINFO(ifa->ifa_ifp)->retrans * hz / 1000); 1139 } else { 1140 int ntick; 1141 1142 if (*tick == 0) 1143 ntick = arc4random() % (MAX_RTR_SOLICITATION_DELAY * hz); 1144 else 1145 ntick = *tick + arc4random() % (hz / 2); 1146 *tick = ntick; 1147 nd6_dad_starttimer(dp, ntick); 1148 } 1149 } 1150 1151 /* 1152 * terminate DAD unconditionally. used for address removals. 1153 */ 1154 void 1155 nd6_dad_stop(ifa) 1156 struct ifaddr *ifa; 1157 { 1158 struct dadq *dp; 1159 1160 if (!dad_init) 1161 return; 1162 dp = nd6_dad_find(ifa); 1163 if (!dp) { 1164 /* DAD wasn't started yet */ 1165 return; 1166 } 1167 1168 nd6_dad_stoptimer(dp); 1169 1170 TAILQ_REMOVE(&dadq, (struct dadq *)dp, dad_list); 1171 free(dp, M_IP6NDP); 1172 dp = NULL; 1173 IFAFREE(ifa); 1174 } 1175 1176 static void 1177 nd6_dad_timer(ifa) 1178 struct ifaddr *ifa; 1179 { 1180 int s; 1181 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1182 struct dadq *dp; 1183 1184 s = splsoftnet(); /* XXX */ 1185 1186 /* Sanity check */ 1187 if (ia == NULL) { 1188 log(LOG_ERR, "nd6_dad_timer: called with null parameter\n"); 1189 goto done; 1190 } 1191 dp = nd6_dad_find(ifa); 1192 if (dp == NULL) { 1193 log(LOG_ERR, "nd6_dad_timer: DAD structure not found\n"); 1194 goto done; 1195 } 1196 if (ia->ia6_flags & IN6_IFF_DUPLICATED) { 1197 log(LOG_ERR, "nd6_dad_timer: called with duplicated address " 1198 "%s(%s)\n", 1199 ip6_sprintf(&ia->ia_addr.sin6_addr), 1200 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1201 goto done; 1202 } 1203 if ((ia->ia6_flags & IN6_IFF_TENTATIVE) == 0) { 1204 log(LOG_ERR, "nd6_dad_timer: called with non-tentative address " 1205 "%s(%s)\n", 1206 ip6_sprintf(&ia->ia_addr.sin6_addr), 1207 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1208 goto done; 1209 } 1210 1211 /* timeouted with IFF_{RUNNING,UP} check */ 1212 if (dp->dad_ns_tcount > dad_maxtry) { 1213 nd6log((LOG_INFO, "%s: could not run DAD, driver problem?\n", 1214 if_name(ifa->ifa_ifp))); 1215 1216 TAILQ_REMOVE(&dadq, (struct dadq *)dp, dad_list); 1217 free(dp, M_IP6NDP); 1218 dp = NULL; 1219 IFAFREE(ifa); 1220 goto done; 1221 } 1222 1223 /* Need more checks? */ 1224 if (dp->dad_ns_ocount < dp->dad_count) { 1225 /* 1226 * We have more NS to go. Send NS packet for DAD. 1227 */ 1228 nd6_dad_ns_output(dp, ifa); 1229 nd6_dad_starttimer(dp, 1230 (long)ND_IFINFO(ifa->ifa_ifp)->retrans * hz / 1000); 1231 } else { 1232 /* 1233 * We have transmitted sufficient number of DAD packets. 1234 * See what we've got. 1235 */ 1236 int duplicate; 1237 1238 duplicate = 0; 1239 1240 if (dp->dad_na_icount) { 1241 /* 1242 * the check is in nd6_dad_na_input(), 1243 * but just in case 1244 */ 1245 duplicate++; 1246 } 1247 1248 if (dp->dad_ns_icount) { 1249 #if 0 /* heuristics */ 1250 /* 1251 * if 1252 * - we have sent many(?) DAD NS, and 1253 * - the number of NS we sent equals to the 1254 * number of NS we've got, and 1255 * - we've got no NA 1256 * we may have a faulty network card/driver which 1257 * loops back multicasts to myself. 1258 */ 1259 if (3 < dp->dad_count 1260 && dp->dad_ns_icount == dp->dad_count 1261 && dp->dad_na_icount == 0) { 1262 log(LOG_INFO, "DAD questionable for %s(%s): " 1263 "network card loops back multicast?\n", 1264 ip6_sprintf(&ia->ia_addr.sin6_addr), 1265 if_name(ifa->ifa_ifp)); 1266 /* XXX consider it a duplicate or not? */ 1267 /* duplicate++; */ 1268 } else { 1269 /* We've seen NS, means DAD has failed. */ 1270 duplicate++; 1271 } 1272 #else 1273 /* We've seen NS, means DAD has failed. */ 1274 duplicate++; 1275 #endif 1276 } 1277 1278 if (duplicate) { 1279 /* (*dp) will be freed in nd6_dad_duplicated() */ 1280 dp = NULL; 1281 nd6_dad_duplicated(ifa); 1282 } else { 1283 /* 1284 * We are done with DAD. No NA came, no NS came. 1285 * duplicated address found. 1286 */ 1287 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1288 1289 nd6log((LOG_DEBUG, 1290 "%s: DAD complete for %s - no duplicates found\n", 1291 if_name(ifa->ifa_ifp), 1292 ip6_sprintf(&ia->ia_addr.sin6_addr))); 1293 1294 TAILQ_REMOVE(&dadq, (struct dadq *)dp, dad_list); 1295 free(dp, M_IP6NDP); 1296 dp = NULL; 1297 IFAFREE(ifa); 1298 } 1299 } 1300 1301 done: 1302 splx(s); 1303 } 1304 1305 void 1306 nd6_dad_duplicated(ifa) 1307 struct ifaddr *ifa; 1308 { 1309 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1310 struct dadq *dp; 1311 1312 dp = nd6_dad_find(ifa); 1313 if (dp == NULL) { 1314 log(LOG_ERR, "nd6_dad_duplicated: DAD structure not found\n"); 1315 return; 1316 } 1317 1318 log(LOG_ERR, "%s: DAD detected duplicate IPv6 address %s: " 1319 "NS in/out=%d/%d, NA in=%d\n", 1320 if_name(ifa->ifa_ifp), ip6_sprintf(&ia->ia_addr.sin6_addr), 1321 dp->dad_ns_icount, dp->dad_ns_ocount, dp->dad_na_icount); 1322 1323 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1324 ia->ia6_flags |= IN6_IFF_DUPLICATED; 1325 1326 /* We are done with DAD, with duplicated address found. (failure) */ 1327 nd6_dad_stoptimer(dp); 1328 1329 log(LOG_ERR, "%s: DAD complete for %s - duplicate found\n", 1330 if_name(ifa->ifa_ifp), ip6_sprintf(&ia->ia_addr.sin6_addr)); 1331 log(LOG_ERR, "%s: manual intervention required\n", 1332 if_name(ifa->ifa_ifp)); 1333 1334 TAILQ_REMOVE(&dadq, (struct dadq *)dp, dad_list); 1335 free(dp, M_IP6NDP); 1336 dp = NULL; 1337 IFAFREE(ifa); 1338 } 1339 1340 static void 1341 nd6_dad_ns_output(dp, ifa) 1342 struct dadq *dp; 1343 struct ifaddr *ifa; 1344 { 1345 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1346 struct ifnet *ifp = ifa->ifa_ifp; 1347 1348 dp->dad_ns_tcount++; 1349 if ((ifp->if_flags & IFF_UP) == 0) { 1350 #if 0 1351 printf("%s: interface down?\n", if_name(ifp)); 1352 #endif 1353 return; 1354 } 1355 if ((ifp->if_flags & IFF_RUNNING) == 0) { 1356 #if 0 1357 printf("%s: interface not running?\n", if_name(ifp)); 1358 #endif 1359 return; 1360 } 1361 1362 dp->dad_ns_ocount++; 1363 nd6_ns_output(ifp, NULL, &ia->ia_addr.sin6_addr, NULL, 1); 1364 } 1365 1366 static void 1367 nd6_dad_ns_input(ifa) 1368 struct ifaddr *ifa; 1369 { 1370 struct in6_ifaddr *ia; 1371 struct ifnet *ifp; 1372 const struct in6_addr *taddr6; 1373 struct dadq *dp; 1374 int duplicate; 1375 1376 if (!ifa) 1377 panic("ifa == NULL in nd6_dad_ns_input"); 1378 1379 ia = (struct in6_ifaddr *)ifa; 1380 ifp = ifa->ifa_ifp; 1381 taddr6 = &ia->ia_addr.sin6_addr; 1382 duplicate = 0; 1383 dp = nd6_dad_find(ifa); 1384 1385 /* Quickhack - completely ignore DAD NS packets */ 1386 if (dad_ignore_ns) { 1387 nd6log((LOG_INFO, 1388 "nd6_dad_ns_input: ignoring DAD NS packet for " 1389 "address %s(%s)\n", ip6_sprintf(taddr6), 1390 if_name(ifa->ifa_ifp))); 1391 return; 1392 } 1393 1394 /* 1395 * if I'm yet to start DAD, someone else started using this address 1396 * first. I have a duplicate and you win. 1397 */ 1398 if (!dp || dp->dad_ns_ocount == 0) 1399 duplicate++; 1400 1401 /* XXX more checks for loopback situation - see nd6_dad_timer too */ 1402 1403 if (duplicate) { 1404 dp = NULL; /* will be freed in nd6_dad_duplicated() */ 1405 nd6_dad_duplicated(ifa); 1406 } else { 1407 /* 1408 * not sure if I got a duplicate. 1409 * increment ns count and see what happens. 1410 */ 1411 if (dp) 1412 dp->dad_ns_icount++; 1413 } 1414 } 1415 1416 static void 1417 nd6_dad_na_input(ifa) 1418 struct ifaddr *ifa; 1419 { 1420 struct dadq *dp; 1421 1422 if (!ifa) 1423 panic("ifa == NULL in nd6_dad_na_input"); 1424 1425 dp = nd6_dad_find(ifa); 1426 if (dp) 1427 dp->dad_na_icount++; 1428 1429 /* remove the address. */ 1430 nd6_dad_duplicated(ifa); 1431 } 1432
Indexes created Sun Oct 26 13:09:57 GMT 2025