nd6_nbr.c revision 1.47
1 /* $NetBSD: nd6_nbr.c,v 1.47 2003/06/27 08:41:09 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 1.47 2003/06/27 08:41:09 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, &im6o, NULL); 511 icmp6_ifstat_inc(ifp, ifs6_out_msg); 512 icmp6_ifstat_inc(ifp, ifs6_out_neighborsolicit); 513 icmp6stat.icp6s_outhist[ND_NEIGHBOR_SOLICIT]++; 514 515 if (ro.ro_rt) { /* we don't cache this route. */ 516 RTFREE(ro.ro_rt); 517 } 518 return; 519 520 bad: 521 if (ro.ro_rt) { 522 RTFREE(ro.ro_rt); 523 } 524 m_freem(m); 525 return; 526 } 527 528 /* 529 * Neighbor advertisement input handling. 530 * 531 * Based on RFC 2461 532 * Based on RFC 2462 (duplicated address detection) 533 * 534 * the following items are not implemented yet: 535 * - proxy advertisement delay rule (RFC2461 7.2.8, last paragraph, SHOULD) 536 * - anycast advertisement delay rule (RFC2461 7.2.7, SHOULD) 537 */ 538 void 539 nd6_na_input(m, off, icmp6len) 540 struct mbuf *m; 541 int off, icmp6len; 542 { 543 struct ifnet *ifp = m->m_pkthdr.rcvif; 544 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 545 struct nd_neighbor_advert *nd_na; 546 #if 0 547 struct in6_addr saddr6 = ip6->ip6_src; 548 #endif 549 struct in6_addr daddr6 = ip6->ip6_dst; 550 struct in6_addr taddr6; 551 int flags; 552 int is_router; 553 int is_solicited; 554 int is_override; 555 char *lladdr = NULL; 556 int lladdrlen = 0; 557 struct ifaddr *ifa; 558 struct llinfo_nd6 *ln; 559 struct rtentry *rt; 560 struct sockaddr_dl *sdl; 561 union nd_opts ndopts; 562 563 if (ip6->ip6_hlim != 255) { 564 nd6log((LOG_ERR, 565 "nd6_na_input: invalid hlim (%d) from %s to %s on %s\n", 566 ip6->ip6_hlim, ip6_sprintf(&ip6->ip6_src), 567 ip6_sprintf(&ip6->ip6_dst), if_name(ifp))); 568 goto bad; 569 } 570 571 IP6_EXTHDR_GET(nd_na, struct nd_neighbor_advert *, m, off, icmp6len); 572 if (nd_na == NULL) { 573 icmp6stat.icp6s_tooshort++; 574 return; 575 } 576 taddr6 = nd_na->nd_na_target; 577 flags = nd_na->nd_na_flags_reserved; 578 is_router = ((flags & ND_NA_FLAG_ROUTER) != 0); 579 is_solicited = ((flags & ND_NA_FLAG_SOLICITED) != 0); 580 is_override = ((flags & ND_NA_FLAG_OVERRIDE) != 0); 581 582 if (IN6_IS_SCOPE_LINKLOCAL(&taddr6)) 583 taddr6.s6_addr16[1] = htons(ifp->if_index); 584 585 if (IN6_IS_ADDR_MULTICAST(&taddr6)) { 586 nd6log((LOG_ERR, 587 "nd6_na_input: invalid target address %s\n", 588 ip6_sprintf(&taddr6))); 589 goto bad; 590 } 591 if (is_solicited && IN6_IS_ADDR_MULTICAST(&daddr6)) { 592 nd6log((LOG_ERR, 593 "nd6_na_input: a solicited adv is multicasted\n")); 594 goto bad; 595 } 596 597 icmp6len -= sizeof(*nd_na); 598 nd6_option_init(nd_na + 1, icmp6len, &ndopts); 599 if (nd6_options(&ndopts) < 0) { 600 nd6log((LOG_INFO, 601 "nd6_na_input: invalid ND option, ignored\n")); 602 /* nd6_options have incremented stats */ 603 goto freeit; 604 } 605 606 if (ndopts.nd_opts_tgt_lladdr) { 607 lladdr = (char *)(ndopts.nd_opts_tgt_lladdr + 1); 608 lladdrlen = ndopts.nd_opts_tgt_lladdr->nd_opt_len << 3; 609 } 610 611 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &taddr6); 612 613 /* 614 * Target address matches one of my interface address. 615 * 616 * If my address is tentative, this means that there's somebody 617 * already using the same address as mine. This indicates DAD failure. 618 * This is defined in RFC 2462. 619 * 620 * Otherwise, process as defined in RFC 2461. 621 */ 622 if (ifa 623 && (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_TENTATIVE)) { 624 nd6_dad_na_input(ifa); 625 goto freeit; 626 } 627 628 /* Just for safety, maybe unnecessary. */ 629 if (ifa) { 630 log(LOG_ERR, 631 "nd6_na_input: duplicate IP6 address %s\n", 632 ip6_sprintf(&taddr6)); 633 goto freeit; 634 } 635 636 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) { 637 nd6log((LOG_INFO, "nd6_na_input: lladdrlen mismatch for %s " 638 "(if %d, NA packet %d)\n", ip6_sprintf(&taddr6), 639 ifp->if_addrlen, lladdrlen - 2)); 640 goto bad; 641 } 642 643 /* 644 * If no neighbor cache entry is found, NA SHOULD silently be 645 * discarded. 646 */ 647 rt = nd6_lookup(&taddr6, 0, ifp); 648 if ((rt == NULL) || 649 ((ln = (struct llinfo_nd6 *)rt->rt_llinfo) == NULL) || 650 ((sdl = SDL(rt->rt_gateway)) == NULL)) 651 goto freeit; 652 653 if (ln->ln_state == ND6_LLINFO_INCOMPLETE) { 654 /* 655 * If the link-layer has address, and no lladdr option came, 656 * discard the packet. 657 */ 658 if (ifp->if_addrlen && !lladdr) 659 goto freeit; 660 661 /* 662 * Record link-layer address, and update the state. 663 */ 664 sdl->sdl_alen = ifp->if_addrlen; 665 bcopy(lladdr, LLADDR(sdl), ifp->if_addrlen); 666 if (is_solicited) { 667 ln->ln_state = ND6_LLINFO_REACHABLE; 668 ln->ln_byhint = 0; 669 if (!ND6_LLINFO_PERMANENT(ln)) { 670 nd6_llinfo_settimer(ln, 671 (long)ND_IFINFO(rt->rt_ifp)->reachable * hz); 672 } 673 } else { 674 ln->ln_state = ND6_LLINFO_STALE; 675 nd6_llinfo_settimer(ln, (long)nd6_gctimer * hz); 676 } 677 if ((ln->ln_router = is_router) != 0) { 678 /* 679 * This means a router's state has changed from 680 * non-reachable to probably reachable, and might 681 * affect the status of associated prefixes.. 682 */ 683 pfxlist_onlink_check(); 684 } 685 } else { 686 int llchange; 687 688 /* 689 * Check if the link-layer address has changed or not. 690 */ 691 if (!lladdr) 692 llchange = 0; 693 else { 694 if (sdl->sdl_alen) { 695 if (bcmp(lladdr, LLADDR(sdl), ifp->if_addrlen)) 696 llchange = 1; 697 else 698 llchange = 0; 699 } else 700 llchange = 1; 701 } 702 703 /* 704 * This is VERY complex. Look at it with care. 705 * 706 * override solicit lladdr llchange action 707 * (L: record lladdr) 708 * 709 * 0 0 n -- (2c) 710 * 0 0 y n (2b) L 711 * 0 0 y y (1) REACHABLE->STALE 712 * 0 1 n -- (2c) *->REACHABLE 713 * 0 1 y n (2b) L *->REACHABLE 714 * 0 1 y y (1) REACHABLE->STALE 715 * 1 0 n -- (2a) 716 * 1 0 y n (2a) L 717 * 1 0 y y (2a) L *->STALE 718 * 1 1 n -- (2a) *->REACHABLE 719 * 1 1 y n (2a) L *->REACHABLE 720 * 1 1 y y (2a) L *->REACHABLE 721 */ 722 if (!is_override && (lladdr && llchange)) { /* (1) */ 723 /* 724 * If state is REACHABLE, make it STALE. 725 * no other updates should be done. 726 */ 727 if (ln->ln_state == ND6_LLINFO_REACHABLE) { 728 ln->ln_state = ND6_LLINFO_STALE; 729 nd6_llinfo_settimer(ln, (long)nd6_gctimer * hz); 730 } 731 goto freeit; 732 } else if (is_override /* (2a) */ 733 || (!is_override && (lladdr && !llchange)) /* (2b) */ 734 || !lladdr) { /* (2c) */ 735 /* 736 * Update link-local address, if any. 737 */ 738 if (lladdr) { 739 sdl->sdl_alen = ifp->if_addrlen; 740 bcopy(lladdr, LLADDR(sdl), ifp->if_addrlen); 741 } 742 743 /* 744 * If solicited, make the state REACHABLE. 745 * If not solicited and the link-layer address was 746 * changed, make it STALE. 747 */ 748 if (is_solicited) { 749 ln->ln_state = ND6_LLINFO_REACHABLE; 750 ln->ln_byhint = 0; 751 if (!ND6_LLINFO_PERMANENT(ln)) { 752 nd6_llinfo_settimer(ln, 753 (long)ND_IFINFO(ifp)->reachable * hz); 754 } 755 } else { 756 if (lladdr && llchange) { 757 ln->ln_state = ND6_LLINFO_STALE; 758 nd6_llinfo_settimer(ln, 759 (long)nd6_gctimer * hz); 760 } 761 } 762 } 763 764 if (ln->ln_router && !is_router) { 765 /* 766 * The peer dropped the router flag. 767 * Remove the sender from the Default Router List and 768 * update the Destination Cache entries. 769 */ 770 struct nd_defrouter *dr; 771 struct in6_addr *in6; 772 int s; 773 774 in6 = &((struct sockaddr_in6 *)rt_key(rt))->sin6_addr; 775 776 /* 777 * Lock to protect the default router list. 778 * XXX: this might be unnecessary, since this function 779 * is only called under the network software interrupt 780 * context. However, we keep it just for safety. 781 */ 782 s = splsoftnet(); 783 dr = defrouter_lookup(in6, rt->rt_ifp); 784 if (dr) 785 defrtrlist_del(dr); 786 else if (!ip6_forwarding) { 787 /* 788 * Even if the neighbor is not in the default 789 * router list, the neighbor may be used 790 * as a next hop for some destinations 791 * (e.g. redirect case). So we must 792 * call rt6_flush explicitly. 793 */ 794 rt6_flush(&ip6->ip6_src, rt->rt_ifp); 795 } 796 splx(s); 797 } 798 ln->ln_router = is_router; 799 } 800 rt->rt_flags &= ~RTF_REJECT; 801 ln->ln_asked = 0; 802 if (ln->ln_hold) { 803 /* 804 * we assume ifp is not a loopback here, so just set the 2nd 805 * argument as the 1st one. 806 */ 807 nd6_output(ifp, ifp, ln->ln_hold, 808 (struct sockaddr_in6 *)rt_key(rt), rt); 809 ln->ln_hold = NULL; 810 } 811 812 freeit: 813 m_freem(m); 814 return; 815 816 bad: 817 icmp6stat.icp6s_badna++; 818 m_freem(m); 819 } 820 821 /* 822 * Neighbor advertisement output handling. 823 * 824 * Based on RFC 2461 825 * 826 * the following items are not implemented yet: 827 * - proxy advertisement delay rule (RFC2461 7.2.8, last paragraph, SHOULD) 828 * - anycast advertisement delay rule (RFC2461 7.2.7, SHOULD) 829 */ 830 void 831 nd6_na_output(ifp, daddr6, taddr6, flags, tlladdr, sdl0) 832 struct ifnet *ifp; 833 const struct in6_addr *daddr6, *taddr6; 834 u_long flags; 835 int tlladdr; /* 1 if include target link-layer address */ 836 struct sockaddr *sdl0; /* sockaddr_dl (= proxy NA) or NULL */ 837 { 838 struct mbuf *m; 839 struct ip6_hdr *ip6; 840 struct nd_neighbor_advert *nd_na; 841 struct ip6_moptions im6o; 842 struct sockaddr_in6 src_sa, dst_sa; 843 struct in6_addr *src0; 844 int icmp6len, maxlen, error; 845 caddr_t mac; 846 struct route_in6 ro; 847 848 mac = NULL; 849 bzero(&ro, sizeof(ro)); 850 851 /* estimate the size of message */ 852 maxlen = sizeof(*ip6) + sizeof(*nd_na); 853 maxlen += (sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7; 854 #ifdef DIAGNOSTIC 855 if (max_linkhdr + maxlen >= MCLBYTES) { 856 printf("nd6_na_output: max_linkhdr + maxlen >= MCLBYTES " 857 "(%d + %d > %d)\n", max_linkhdr, maxlen, MCLBYTES); 858 panic("nd6_na_output: insufficient MCLBYTES"); 859 /* NOTREACHED */ 860 } 861 #endif 862 863 MGETHDR(m, M_DONTWAIT, MT_DATA); 864 if (m && max_linkhdr + maxlen >= MHLEN) { 865 MCLGET(m, M_DONTWAIT); 866 if ((m->m_flags & M_EXT) == 0) { 867 m_free(m); 868 m = NULL; 869 } 870 } 871 if (m == NULL) 872 return; 873 m->m_pkthdr.rcvif = NULL; 874 875 if (IN6_IS_ADDR_MULTICAST(daddr6)) { 876 m->m_flags |= M_MCAST; 877 im6o.im6o_multicast_ifp = ifp; 878 im6o.im6o_multicast_hlim = 255; 879 im6o.im6o_multicast_loop = 0; 880 } 881 882 icmp6len = sizeof(*nd_na); 883 m->m_pkthdr.len = m->m_len = sizeof(struct ip6_hdr) + icmp6len; 884 m->m_data += max_linkhdr; /* or MH_ALIGN() equivalent? */ 885 886 /* fill neighbor advertisement packet */ 887 ip6 = mtod(m, struct ip6_hdr *); 888 ip6->ip6_flow = 0; 889 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 890 ip6->ip6_vfc |= IPV6_VERSION; 891 ip6->ip6_nxt = IPPROTO_ICMPV6; 892 ip6->ip6_hlim = 255; 893 bzero(&src_sa, sizeof(src_sa)); 894 bzero(&dst_sa, sizeof(dst_sa)); 895 src_sa.sin6_len = dst_sa.sin6_len = sizeof(struct sockaddr_in6); 896 src_sa.sin6_family = dst_sa.sin6_family = AF_INET6; 897 dst_sa.sin6_addr = *daddr6; 898 if (IN6_IS_ADDR_UNSPECIFIED(daddr6)) { 899 /* reply to DAD */ 900 dst_sa.sin6_addr.s6_addr16[0] = IPV6_ADDR_INT16_MLL; 901 dst_sa.sin6_addr.s6_addr16[1] = htons(ifp->if_index); 902 dst_sa.sin6_addr.s6_addr32[1] = 0; 903 dst_sa.sin6_addr.s6_addr32[2] = 0; 904 dst_sa.sin6_addr.s6_addr32[3] = IPV6_ADDR_INT32_ONE; 905 906 flags &= ~ND_NA_FLAG_SOLICITED; 907 } 908 ip6->ip6_dst = dst_sa.sin6_addr; 909 910 /* 911 * Select a source whose scope is the same as that of the dest. 912 */ 913 bcopy(&dst_sa, &ro.ro_dst, sizeof(dst_sa)); 914 src0 = in6_selectsrc(&dst_sa, NULL, NULL, &ro, NULL, &error); 915 if (src0 == NULL) { 916 nd6log((LOG_DEBUG, "nd6_na_output: source can't be " 917 "determined: dst=%s, error=%d\n", 918 ip6_sprintf(&dst_sa.sin6_addr), error)); 919 goto bad; 920 } 921 src_sa.sin6_addr = *src0; 922 ip6->ip6_src = src_sa.sin6_addr; 923 nd_na = (struct nd_neighbor_advert *)(ip6 + 1); 924 nd_na->nd_na_type = ND_NEIGHBOR_ADVERT; 925 nd_na->nd_na_code = 0; 926 nd_na->nd_na_target = *taddr6; 927 if (IN6_IS_SCOPE_LINKLOCAL(&nd_na->nd_na_target)) 928 nd_na->nd_na_target.s6_addr16[1] = 0; 929 930 /* 931 * "tlladdr" indicates NS's condition for adding tlladdr or not. 932 * see nd6_ns_input() for details. 933 * Basically, if NS packet is sent to unicast/anycast addr, 934 * target lladdr option SHOULD NOT be included. 935 */ 936 if (tlladdr) { 937 /* 938 * sdl0 != NULL indicates proxy NA. If we do proxy, use 939 * lladdr in sdl0. If we are not proxying (sending NA for 940 * my address) use lladdr configured for the interface. 941 */ 942 if (sdl0 == NULL) 943 mac = nd6_ifptomac(ifp); 944 else if (sdl0->sa_family == AF_LINK) { 945 struct sockaddr_dl *sdl; 946 sdl = (struct sockaddr_dl *)sdl0; 947 if (sdl->sdl_alen == ifp->if_addrlen) 948 mac = LLADDR(sdl); 949 } 950 } 951 if (tlladdr && mac) { 952 int optlen = sizeof(struct nd_opt_hdr) + ifp->if_addrlen; 953 struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)(nd_na + 1); 954 955 /* roundup to 8 bytes alignment! */ 956 optlen = (optlen + 7) & ~7; 957 958 m->m_pkthdr.len += optlen; 959 m->m_len += optlen; 960 icmp6len += optlen; 961 bzero((caddr_t)nd_opt, optlen); 962 nd_opt->nd_opt_type = ND_OPT_TARGET_LINKADDR; 963 nd_opt->nd_opt_len = optlen >> 3; 964 bcopy(mac, (caddr_t)(nd_opt + 1), ifp->if_addrlen); 965 } else 966 flags &= ~ND_NA_FLAG_OVERRIDE; 967 968 ip6->ip6_plen = htons((u_short)icmp6len); 969 nd_na->nd_na_flags_reserved = flags; 970 nd_na->nd_na_cksum = 0; 971 nd_na->nd_na_cksum = 972 in6_cksum(m, IPPROTO_ICMPV6, sizeof(struct ip6_hdr), icmp6len); 973 974 #ifdef IPSEC 975 /* Don't lookup socket */ 976 (void)ipsec_setsocket(m, NULL); 977 #endif 978 ip6_output(m, NULL, NULL, 0, &im6o, NULL); 979 980 icmp6_ifstat_inc(ifp, ifs6_out_msg); 981 icmp6_ifstat_inc(ifp, ifs6_out_neighboradvert); 982 icmp6stat.icp6s_outhist[ND_NEIGHBOR_ADVERT]++; 983 984 if (ro.ro_rt) { /* we don't cache this route. */ 985 RTFREE(ro.ro_rt); 986 } 987 return; 988 989 bad: 990 if (ro.ro_rt) { 991 RTFREE(ro.ro_rt); 992 } 993 m_freem(m); 994 return; 995 } 996 997 caddr_t 998 nd6_ifptomac(ifp) 999 struct ifnet *ifp; 1000 { 1001 switch (ifp->if_type) { 1002 case IFT_ARCNET: 1003 case IFT_ETHER: 1004 case IFT_FDDI: 1005 case IFT_IEEE1394: 1006 case IFT_PROPVIRTUAL: 1007 case IFT_L2VLAN: 1008 case IFT_IEEE80211: 1009 return LLADDR(ifp->if_sadl); 1010 default: 1011 return NULL; 1012 } 1013 } 1014 1015 TAILQ_HEAD(dadq_head, dadq); 1016 struct dadq { 1017 TAILQ_ENTRY(dadq) dad_list; 1018 struct ifaddr *dad_ifa; 1019 int dad_count; /* max NS to send */ 1020 int dad_ns_tcount; /* # of trials to send NS */ 1021 int dad_ns_ocount; /* NS sent so far */ 1022 int dad_ns_icount; 1023 int dad_na_icount; 1024 struct callout dad_timer_ch; 1025 }; 1026 1027 static struct dadq_head dadq; 1028 static int dad_init = 0; 1029 1030 static struct dadq * 1031 nd6_dad_find(ifa) 1032 struct ifaddr *ifa; 1033 { 1034 struct dadq *dp; 1035 1036 for (dp = dadq.tqh_first; dp; dp = dp->dad_list.tqe_next) { 1037 if (dp->dad_ifa == ifa) 1038 return dp; 1039 } 1040 return NULL; 1041 } 1042 1043 static void 1044 nd6_dad_starttimer(dp, ticks) 1045 struct dadq *dp; 1046 int ticks; 1047 { 1048 1049 callout_reset(&dp->dad_timer_ch, ticks, 1050 (void (*) __P((void *)))nd6_dad_timer, (void *)dp->dad_ifa); 1051 } 1052 1053 static void 1054 nd6_dad_stoptimer(dp) 1055 struct dadq *dp; 1056 { 1057 1058 callout_stop(&dp->dad_timer_ch); 1059 } 1060 1061 /* 1062 * Start Duplicated Address Detection (DAD) for specified interface address. 1063 */ 1064 void 1065 nd6_dad_start(ifa, tick) 1066 struct ifaddr *ifa; 1067 int *tick; /* minimum delay ticks for IFF_UP event */ 1068 { 1069 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1070 struct dadq *dp; 1071 1072 if (!dad_init) { 1073 TAILQ_INIT(&dadq); 1074 dad_init++; 1075 } 1076 1077 /* 1078 * If we don't need DAD, don't do it. 1079 * There are several cases: 1080 * - DAD is disabled (ip6_dad_count == 0) 1081 * - the interface address is anycast 1082 */ 1083 if (!(ia->ia6_flags & IN6_IFF_TENTATIVE)) { 1084 log(LOG_DEBUG, 1085 "nd6_dad_start: called with non-tentative address " 1086 "%s(%s)\n", 1087 ip6_sprintf(&ia->ia_addr.sin6_addr), 1088 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1089 return; 1090 } 1091 if (ia->ia6_flags & IN6_IFF_ANYCAST) { 1092 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1093 return; 1094 } 1095 if (!ip6_dad_count) { 1096 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1097 return; 1098 } 1099 if (!ifa->ifa_ifp) 1100 panic("nd6_dad_start: ifa->ifa_ifp == NULL"); 1101 if (!(ifa->ifa_ifp->if_flags & IFF_UP)) 1102 return; 1103 if (nd6_dad_find(ifa) != NULL) { 1104 /* DAD already in progress */ 1105 return; 1106 } 1107 1108 dp = malloc(sizeof(*dp), M_IP6NDP, M_NOWAIT); 1109 if (dp == NULL) { 1110 log(LOG_ERR, "nd6_dad_start: memory allocation failed for " 1111 "%s(%s)\n", 1112 ip6_sprintf(&ia->ia_addr.sin6_addr), 1113 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1114 return; 1115 } 1116 bzero(dp, sizeof(*dp)); 1117 callout_init(&dp->dad_timer_ch); 1118 TAILQ_INSERT_TAIL(&dadq, (struct dadq *)dp, dad_list); 1119 1120 nd6log((LOG_DEBUG, "%s: starting DAD for %s\n", if_name(ifa->ifa_ifp), 1121 ip6_sprintf(&ia->ia_addr.sin6_addr))); 1122 1123 /* 1124 * Send NS packet for DAD, ip6_dad_count times. 1125 * Note that we must delay the first transmission, if this is the 1126 * first packet to be sent from the interface after interface 1127 * (re)initialization. 1128 */ 1129 dp->dad_ifa = ifa; 1130 IFAREF(ifa); /* just for safety */ 1131 dp->dad_count = ip6_dad_count; 1132 dp->dad_ns_icount = dp->dad_na_icount = 0; 1133 dp->dad_ns_ocount = dp->dad_ns_tcount = 0; 1134 if (tick == NULL) { 1135 nd6_dad_ns_output(dp, ifa); 1136 nd6_dad_starttimer(dp, 1137 (long)ND_IFINFO(ifa->ifa_ifp)->retrans * hz / 1000); 1138 } else { 1139 int ntick; 1140 1141 if (*tick == 0) 1142 ntick = arc4random() % (MAX_RTR_SOLICITATION_DELAY * hz); 1143 else 1144 ntick = *tick + arc4random() % (hz / 2); 1145 *tick = ntick; 1146 nd6_dad_starttimer(dp, ntick); 1147 } 1148 } 1149 1150 /* 1151 * terminate DAD unconditionally. used for address removals. 1152 */ 1153 void 1154 nd6_dad_stop(ifa) 1155 struct ifaddr *ifa; 1156 { 1157 struct dadq *dp; 1158 1159 if (!dad_init) 1160 return; 1161 dp = nd6_dad_find(ifa); 1162 if (!dp) { 1163 /* DAD wasn't started yet */ 1164 return; 1165 } 1166 1167 nd6_dad_stoptimer(dp); 1168 1169 TAILQ_REMOVE(&dadq, (struct dadq *)dp, dad_list); 1170 free(dp, M_IP6NDP); 1171 dp = NULL; 1172 IFAFREE(ifa); 1173 } 1174 1175 static void 1176 nd6_dad_timer(ifa) 1177 struct ifaddr *ifa; 1178 { 1179 int s; 1180 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1181 struct dadq *dp; 1182 1183 s = splsoftnet(); /* XXX */ 1184 1185 /* Sanity check */ 1186 if (ia == NULL) { 1187 log(LOG_ERR, "nd6_dad_timer: called with null parameter\n"); 1188 goto done; 1189 } 1190 dp = nd6_dad_find(ifa); 1191 if (dp == NULL) { 1192 log(LOG_ERR, "nd6_dad_timer: DAD structure not found\n"); 1193 goto done; 1194 } 1195 if (ia->ia6_flags & IN6_IFF_DUPLICATED) { 1196 log(LOG_ERR, "nd6_dad_timer: called with duplicated address " 1197 "%s(%s)\n", 1198 ip6_sprintf(&ia->ia_addr.sin6_addr), 1199 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1200 goto done; 1201 } 1202 if ((ia->ia6_flags & IN6_IFF_TENTATIVE) == 0) { 1203 log(LOG_ERR, "nd6_dad_timer: called with non-tentative address " 1204 "%s(%s)\n", 1205 ip6_sprintf(&ia->ia_addr.sin6_addr), 1206 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1207 goto done; 1208 } 1209 1210 /* timeouted with IFF_{RUNNING,UP} check */ 1211 if (dp->dad_ns_tcount > dad_maxtry) { 1212 nd6log((LOG_INFO, "%s: could not run DAD, driver problem?\n", 1213 if_name(ifa->ifa_ifp))); 1214 1215 TAILQ_REMOVE(&dadq, (struct dadq *)dp, dad_list); 1216 free(dp, M_IP6NDP); 1217 dp = NULL; 1218 IFAFREE(ifa); 1219 goto done; 1220 } 1221 1222 /* Need more checks? */ 1223 if (dp->dad_ns_ocount < dp->dad_count) { 1224 /* 1225 * We have more NS to go. Send NS packet for DAD. 1226 */ 1227 nd6_dad_ns_output(dp, ifa); 1228 nd6_dad_starttimer(dp, 1229 (long)ND_IFINFO(ifa->ifa_ifp)->retrans * hz / 1000); 1230 } else { 1231 /* 1232 * We have transmitted sufficient number of DAD packets. 1233 * See what we've got. 1234 */ 1235 int duplicate; 1236 1237 duplicate = 0; 1238 1239 if (dp->dad_na_icount) { 1240 /* 1241 * the check is in nd6_dad_na_input(), 1242 * but just in case 1243 */ 1244 duplicate++; 1245 } 1246 1247 if (dp->dad_ns_icount) { 1248 #if 0 /* heuristics */ 1249 /* 1250 * if 1251 * - we have sent many(?) DAD NS, and 1252 * - the number of NS we sent equals to the 1253 * number of NS we've got, and 1254 * - we've got no NA 1255 * we may have a faulty network card/driver which 1256 * loops back multicasts to myself. 1257 */ 1258 if (3 < dp->dad_count 1259 && dp->dad_ns_icount == dp->dad_count 1260 && dp->dad_na_icount == 0) { 1261 log(LOG_INFO, "DAD questionable for %s(%s): " 1262 "network card loops back multicast?\n", 1263 ip6_sprintf(&ia->ia_addr.sin6_addr), 1264 if_name(ifa->ifa_ifp)); 1265 /* XXX consider it a duplicate or not? */ 1266 /* duplicate++; */ 1267 } else { 1268 /* We've seen NS, means DAD has failed. */ 1269 duplicate++; 1270 } 1271 #else 1272 /* We've seen NS, means DAD has failed. */ 1273 duplicate++; 1274 #endif 1275 } 1276 1277 if (duplicate) { 1278 /* (*dp) will be freed in nd6_dad_duplicated() */ 1279 dp = NULL; 1280 nd6_dad_duplicated(ifa); 1281 } else { 1282 /* 1283 * We are done with DAD. No NA came, no NS came. 1284 * duplicated address found. 1285 */ 1286 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1287 1288 nd6log((LOG_DEBUG, 1289 "%s: DAD complete for %s - no duplicates found\n", 1290 if_name(ifa->ifa_ifp), 1291 ip6_sprintf(&ia->ia_addr.sin6_addr))); 1292 1293 TAILQ_REMOVE(&dadq, (struct dadq *)dp, dad_list); 1294 free(dp, M_IP6NDP); 1295 dp = NULL; 1296 IFAFREE(ifa); 1297 } 1298 } 1299 1300 done: 1301 splx(s); 1302 } 1303 1304 void 1305 nd6_dad_duplicated(ifa) 1306 struct ifaddr *ifa; 1307 { 1308 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1309 struct dadq *dp; 1310 1311 dp = nd6_dad_find(ifa); 1312 if (dp == NULL) { 1313 log(LOG_ERR, "nd6_dad_duplicated: DAD structure not found\n"); 1314 return; 1315 } 1316 1317 log(LOG_ERR, "%s: DAD detected duplicate IPv6 address %s: " 1318 "NS in/out=%d/%d, NA in=%d\n", 1319 if_name(ifa->ifa_ifp), ip6_sprintf(&ia->ia_addr.sin6_addr), 1320 dp->dad_ns_icount, dp->dad_ns_ocount, dp->dad_na_icount); 1321 1322 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1323 ia->ia6_flags |= IN6_IFF_DUPLICATED; 1324 1325 /* We are done with DAD, with duplicated address found. (failure) */ 1326 nd6_dad_stoptimer(dp); 1327 1328 log(LOG_ERR, "%s: DAD complete for %s - duplicate found\n", 1329 if_name(ifa->ifa_ifp), ip6_sprintf(&ia->ia_addr.sin6_addr)); 1330 log(LOG_ERR, "%s: manual intervention required\n", 1331 if_name(ifa->ifa_ifp)); 1332 1333 TAILQ_REMOVE(&dadq, (struct dadq *)dp, dad_list); 1334 free(dp, M_IP6NDP); 1335 dp = NULL; 1336 IFAFREE(ifa); 1337 } 1338 1339 static void 1340 nd6_dad_ns_output(dp, ifa) 1341 struct dadq *dp; 1342 struct ifaddr *ifa; 1343 { 1344 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1345 struct ifnet *ifp = ifa->ifa_ifp; 1346 1347 dp->dad_ns_tcount++; 1348 if ((ifp->if_flags & IFF_UP) == 0) { 1349 #if 0 1350 printf("%s: interface down?\n", if_name(ifp)); 1351 #endif 1352 return; 1353 } 1354 if ((ifp->if_flags & IFF_RUNNING) == 0) { 1355 #if 0 1356 printf("%s: interface not running?\n", if_name(ifp)); 1357 #endif 1358 return; 1359 } 1360 1361 dp->dad_ns_ocount++; 1362 nd6_ns_output(ifp, NULL, &ia->ia_addr.sin6_addr, NULL, 1); 1363 } 1364 1365 static void 1366 nd6_dad_ns_input(ifa) 1367 struct ifaddr *ifa; 1368 { 1369 struct in6_ifaddr *ia; 1370 struct ifnet *ifp; 1371 const struct in6_addr *taddr6; 1372 struct dadq *dp; 1373 int duplicate; 1374 1375 if (!ifa) 1376 panic("ifa == NULL in nd6_dad_ns_input"); 1377 1378 ia = (struct in6_ifaddr *)ifa; 1379 ifp = ifa->ifa_ifp; 1380 taddr6 = &ia->ia_addr.sin6_addr; 1381 duplicate = 0; 1382 dp = nd6_dad_find(ifa); 1383 1384 /* Quickhack - completely ignore DAD NS packets */ 1385 if (dad_ignore_ns) { 1386 nd6log((LOG_INFO, 1387 "nd6_dad_ns_input: ignoring DAD NS packet for " 1388 "address %s(%s)\n", ip6_sprintf(taddr6), 1389 if_name(ifa->ifa_ifp))); 1390 return; 1391 } 1392 1393 /* 1394 * if I'm yet to start DAD, someone else started using this address 1395 * first. I have a duplicate and you win. 1396 */ 1397 if (!dp || dp->dad_ns_ocount == 0) 1398 duplicate++; 1399 1400 /* XXX more checks for loopback situation - see nd6_dad_timer too */ 1401 1402 if (duplicate) { 1403 dp = NULL; /* will be freed in nd6_dad_duplicated() */ 1404 nd6_dad_duplicated(ifa); 1405 } else { 1406 /* 1407 * not sure if I got a duplicate. 1408 * increment ns count and see what happens. 1409 */ 1410 if (dp) 1411 dp->dad_ns_icount++; 1412 } 1413 } 1414 1415 static void 1416 nd6_dad_na_input(ifa) 1417 struct ifaddr *ifa; 1418 { 1419 struct dadq *dp; 1420 1421 if (!ifa) 1422 panic("ifa == NULL in nd6_dad_na_input"); 1423 1424 dp = nd6_dad_find(ifa); 1425 if (dp) 1426 dp->dad_na_icount++; 1427 1428 /* remove the address. */ 1429 nd6_dad_duplicated(ifa); 1430 } 1431
Indexes created Tue Sep 30 11:09:46 GMT 2025