nd6_nbr.c revision 1.46
1 /* $NetBSD: nd6_nbr.c,v 1.46 2003/06/24 07:54:48 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 1.46 2003/06/24 07:54:48 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 (ln->ln_expire) 670 ln->ln_expire = time.tv_sec + 671 ND_IFINFO(rt->rt_ifp)->reachable; 672 } else { 673 ln->ln_state = ND6_LLINFO_STALE; 674 ln->ln_expire = time.tv_sec + nd6_gctimer; 675 } 676 if ((ln->ln_router = is_router) != 0) { 677 /* 678 * This means a router's state has changed from 679 * non-reachable to probably reachable, and might 680 * affect the status of associated prefixes.. 681 */ 682 pfxlist_onlink_check(); 683 } 684 } else { 685 int llchange; 686 687 /* 688 * Check if the link-layer address has changed or not. 689 */ 690 if (!lladdr) 691 llchange = 0; 692 else { 693 if (sdl->sdl_alen) { 694 if (bcmp(lladdr, LLADDR(sdl), ifp->if_addrlen)) 695 llchange = 1; 696 else 697 llchange = 0; 698 } else 699 llchange = 1; 700 } 701 702 /* 703 * This is VERY complex. Look at it with care. 704 * 705 * override solicit lladdr llchange action 706 * (L: record lladdr) 707 * 708 * 0 0 n -- (2c) 709 * 0 0 y n (2b) L 710 * 0 0 y y (1) REACHABLE->STALE 711 * 0 1 n -- (2c) *->REACHABLE 712 * 0 1 y n (2b) L *->REACHABLE 713 * 0 1 y y (1) REACHABLE->STALE 714 * 1 0 n -- (2a) 715 * 1 0 y n (2a) L 716 * 1 0 y y (2a) L *->STALE 717 * 1 1 n -- (2a) *->REACHABLE 718 * 1 1 y n (2a) L *->REACHABLE 719 * 1 1 y y (2a) L *->REACHABLE 720 */ 721 if (!is_override && (lladdr && llchange)) { /* (1) */ 722 /* 723 * If state is REACHABLE, make it STALE. 724 * no other updates should be done. 725 */ 726 if (ln->ln_state == ND6_LLINFO_REACHABLE) { 727 ln->ln_state = ND6_LLINFO_STALE; 728 ln->ln_expire = time.tv_sec + nd6_gctimer; 729 } 730 goto freeit; 731 } else if (is_override /* (2a) */ 732 || (!is_override && (lladdr && !llchange)) /* (2b) */ 733 || !lladdr) { /* (2c) */ 734 /* 735 * Update link-local address, if any. 736 */ 737 if (lladdr) { 738 sdl->sdl_alen = ifp->if_addrlen; 739 bcopy(lladdr, LLADDR(sdl), ifp->if_addrlen); 740 } 741 742 /* 743 * If solicited, make the state REACHABLE. 744 * If not solicited and the link-layer address was 745 * changed, make it STALE. 746 */ 747 if (is_solicited) { 748 ln->ln_state = ND6_LLINFO_REACHABLE; 749 ln->ln_byhint = 0; 750 if (ln->ln_expire) { 751 ln->ln_expire = time.tv_sec + 752 ND_IFINFO(ifp)->reachable; 753 } 754 } else { 755 if (lladdr && llchange) { 756 ln->ln_state = ND6_LLINFO_STALE; 757 ln->ln_expire = time.tv_sec + nd6_gctimer; 758 } 759 } 760 } 761 762 if (ln->ln_router && !is_router) { 763 /* 764 * The peer dropped the router flag. 765 * Remove the sender from the Default Router List and 766 * update the Destination Cache entries. 767 */ 768 struct nd_defrouter *dr; 769 struct in6_addr *in6; 770 int s; 771 772 in6 = &((struct sockaddr_in6 *)rt_key(rt))->sin6_addr; 773 774 /* 775 * Lock to protect the default router list. 776 * XXX: this might be unnecessary, since this function 777 * is only called under the network software interrupt 778 * context. However, we keep it just for safety. 779 */ 780 s = splsoftnet(); 781 dr = defrouter_lookup(in6, rt->rt_ifp); 782 if (dr) 783 defrtrlist_del(dr); 784 else if (!ip6_forwarding) { 785 /* 786 * Even if the neighbor is not in the default 787 * router list, the neighbor may be used 788 * as a next hop for some destinations 789 * (e.g. redirect case). So we must 790 * call rt6_flush explicitly. 791 */ 792 rt6_flush(&ip6->ip6_src, rt->rt_ifp); 793 } 794 splx(s); 795 } 796 ln->ln_router = is_router; 797 } 798 rt->rt_flags &= ~RTF_REJECT; 799 ln->ln_asked = 0; 800 if (ln->ln_hold) { 801 /* 802 * we assume ifp is not a loopback here, so just set the 2nd 803 * argument as the 1st one. 804 */ 805 nd6_output(ifp, ifp, ln->ln_hold, 806 (struct sockaddr_in6 *)rt_key(rt), rt); 807 ln->ln_hold = NULL; 808 } 809 810 freeit: 811 m_freem(m); 812 return; 813 814 bad: 815 icmp6stat.icp6s_badna++; 816 m_freem(m); 817 } 818 819 /* 820 * Neighbor advertisement output handling. 821 * 822 * Based on RFC 2461 823 * 824 * the following items are not implemented yet: 825 * - proxy advertisement delay rule (RFC2461 7.2.8, last paragraph, SHOULD) 826 * - anycast advertisement delay rule (RFC2461 7.2.7, SHOULD) 827 */ 828 void 829 nd6_na_output(ifp, daddr6, taddr6, flags, tlladdr, sdl0) 830 struct ifnet *ifp; 831 const struct in6_addr *daddr6, *taddr6; 832 u_long flags; 833 int tlladdr; /* 1 if include target link-layer address */ 834 struct sockaddr *sdl0; /* sockaddr_dl (= proxy NA) or NULL */ 835 { 836 struct mbuf *m; 837 struct ip6_hdr *ip6; 838 struct nd_neighbor_advert *nd_na; 839 struct ip6_moptions im6o; 840 struct sockaddr_in6 src_sa, dst_sa; 841 struct in6_addr *src0; 842 int icmp6len, maxlen, error; 843 caddr_t mac; 844 struct route_in6 ro; 845 846 mac = NULL; 847 bzero(&ro, sizeof(ro)); 848 849 /* estimate the size of message */ 850 maxlen = sizeof(*ip6) + sizeof(*nd_na); 851 maxlen += (sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7; 852 #ifdef DIAGNOSTIC 853 if (max_linkhdr + maxlen >= MCLBYTES) { 854 printf("nd6_na_output: max_linkhdr + maxlen >= MCLBYTES " 855 "(%d + %d > %d)\n", max_linkhdr, maxlen, MCLBYTES); 856 panic("nd6_na_output: insufficient MCLBYTES"); 857 /* NOTREACHED */ 858 } 859 #endif 860 861 MGETHDR(m, M_DONTWAIT, MT_DATA); 862 if (m && max_linkhdr + maxlen >= MHLEN) { 863 MCLGET(m, M_DONTWAIT); 864 if ((m->m_flags & M_EXT) == 0) { 865 m_free(m); 866 m = NULL; 867 } 868 } 869 if (m == NULL) 870 return; 871 m->m_pkthdr.rcvif = NULL; 872 873 if (IN6_IS_ADDR_MULTICAST(daddr6)) { 874 m->m_flags |= M_MCAST; 875 im6o.im6o_multicast_ifp = ifp; 876 im6o.im6o_multicast_hlim = 255; 877 im6o.im6o_multicast_loop = 0; 878 } 879 880 icmp6len = sizeof(*nd_na); 881 m->m_pkthdr.len = m->m_len = sizeof(struct ip6_hdr) + icmp6len; 882 m->m_data += max_linkhdr; /* or MH_ALIGN() equivalent? */ 883 884 /* fill neighbor advertisement packet */ 885 ip6 = mtod(m, struct ip6_hdr *); 886 ip6->ip6_flow = 0; 887 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 888 ip6->ip6_vfc |= IPV6_VERSION; 889 ip6->ip6_nxt = IPPROTO_ICMPV6; 890 ip6->ip6_hlim = 255; 891 bzero(&src_sa, sizeof(src_sa)); 892 bzero(&dst_sa, sizeof(dst_sa)); 893 src_sa.sin6_len = dst_sa.sin6_len = sizeof(struct sockaddr_in6); 894 src_sa.sin6_family = dst_sa.sin6_family = AF_INET6; 895 dst_sa.sin6_addr = *daddr6; 896 if (IN6_IS_ADDR_UNSPECIFIED(daddr6)) { 897 /* reply to DAD */ 898 dst_sa.sin6_addr.s6_addr16[0] = IPV6_ADDR_INT16_MLL; 899 dst_sa.sin6_addr.s6_addr16[1] = htons(ifp->if_index); 900 dst_sa.sin6_addr.s6_addr32[1] = 0; 901 dst_sa.sin6_addr.s6_addr32[2] = 0; 902 dst_sa.sin6_addr.s6_addr32[3] = IPV6_ADDR_INT32_ONE; 903 904 flags &= ~ND_NA_FLAG_SOLICITED; 905 } 906 ip6->ip6_dst = dst_sa.sin6_addr; 907 908 /* 909 * Select a source whose scope is the same as that of the dest. 910 */ 911 bcopy(&dst_sa, &ro.ro_dst, sizeof(dst_sa)); 912 src0 = in6_selectsrc(&dst_sa, NULL, NULL, &ro, NULL, &error); 913 if (src0 == NULL) { 914 nd6log((LOG_DEBUG, "nd6_na_output: source can't be " 915 "determined: dst=%s, error=%d\n", 916 ip6_sprintf(&dst_sa.sin6_addr), error)); 917 goto bad; 918 } 919 src_sa.sin6_addr = *src0; 920 ip6->ip6_src = src_sa.sin6_addr; 921 nd_na = (struct nd_neighbor_advert *)(ip6 + 1); 922 nd_na->nd_na_type = ND_NEIGHBOR_ADVERT; 923 nd_na->nd_na_code = 0; 924 nd_na->nd_na_target = *taddr6; 925 if (IN6_IS_SCOPE_LINKLOCAL(&nd_na->nd_na_target)) 926 nd_na->nd_na_target.s6_addr16[1] = 0; 927 928 /* 929 * "tlladdr" indicates NS's condition for adding tlladdr or not. 930 * see nd6_ns_input() for details. 931 * Basically, if NS packet is sent to unicast/anycast addr, 932 * target lladdr option SHOULD NOT be included. 933 */ 934 if (tlladdr) { 935 /* 936 * sdl0 != NULL indicates proxy NA. If we do proxy, use 937 * lladdr in sdl0. If we are not proxying (sending NA for 938 * my address) use lladdr configured for the interface. 939 */ 940 if (sdl0 == NULL) 941 mac = nd6_ifptomac(ifp); 942 else if (sdl0->sa_family == AF_LINK) { 943 struct sockaddr_dl *sdl; 944 sdl = (struct sockaddr_dl *)sdl0; 945 if (sdl->sdl_alen == ifp->if_addrlen) 946 mac = LLADDR(sdl); 947 } 948 } 949 if (tlladdr && mac) { 950 int optlen = sizeof(struct nd_opt_hdr) + ifp->if_addrlen; 951 struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)(nd_na + 1); 952 953 /* roundup to 8 bytes alignment! */ 954 optlen = (optlen + 7) & ~7; 955 956 m->m_pkthdr.len += optlen; 957 m->m_len += optlen; 958 icmp6len += optlen; 959 bzero((caddr_t)nd_opt, optlen); 960 nd_opt->nd_opt_type = ND_OPT_TARGET_LINKADDR; 961 nd_opt->nd_opt_len = optlen >> 3; 962 bcopy(mac, (caddr_t)(nd_opt + 1), ifp->if_addrlen); 963 } else 964 flags &= ~ND_NA_FLAG_OVERRIDE; 965 966 ip6->ip6_plen = htons((u_short)icmp6len); 967 nd_na->nd_na_flags_reserved = flags; 968 nd_na->nd_na_cksum = 0; 969 nd_na->nd_na_cksum = 970 in6_cksum(m, IPPROTO_ICMPV6, sizeof(struct ip6_hdr), icmp6len); 971 972 #ifdef IPSEC 973 /* Don't lookup socket */ 974 (void)ipsec_setsocket(m, NULL); 975 #endif 976 ip6_output(m, NULL, NULL, 0, &im6o, NULL); 977 978 icmp6_ifstat_inc(ifp, ifs6_out_msg); 979 icmp6_ifstat_inc(ifp, ifs6_out_neighboradvert); 980 icmp6stat.icp6s_outhist[ND_NEIGHBOR_ADVERT]++; 981 982 if (ro.ro_rt) { /* we don't cache this route. */ 983 RTFREE(ro.ro_rt); 984 } 985 return; 986 987 bad: 988 if (ro.ro_rt) { 989 RTFREE(ro.ro_rt); 990 } 991 m_freem(m); 992 return; 993 } 994 995 caddr_t 996 nd6_ifptomac(ifp) 997 struct ifnet *ifp; 998 { 999 switch (ifp->if_type) { 1000 case IFT_ARCNET: 1001 case IFT_ETHER: 1002 case IFT_FDDI: 1003 case IFT_IEEE1394: 1004 case IFT_PROPVIRTUAL: 1005 case IFT_L2VLAN: 1006 case IFT_IEEE80211: 1007 return LLADDR(ifp->if_sadl); 1008 default: 1009 return NULL; 1010 } 1011 } 1012 1013 TAILQ_HEAD(dadq_head, dadq); 1014 struct dadq { 1015 TAILQ_ENTRY(dadq) dad_list; 1016 struct ifaddr *dad_ifa; 1017 int dad_count; /* max NS to send */ 1018 int dad_ns_tcount; /* # of trials to send NS */ 1019 int dad_ns_ocount; /* NS sent so far */ 1020 int dad_ns_icount; 1021 int dad_na_icount; 1022 struct callout dad_timer_ch; 1023 }; 1024 1025 static struct dadq_head dadq; 1026 static int dad_init = 0; 1027 1028 static struct dadq * 1029 nd6_dad_find(ifa) 1030 struct ifaddr *ifa; 1031 { 1032 struct dadq *dp; 1033 1034 for (dp = dadq.tqh_first; dp; dp = dp->dad_list.tqe_next) { 1035 if (dp->dad_ifa == ifa) 1036 return dp; 1037 } 1038 return NULL; 1039 } 1040 1041 static void 1042 nd6_dad_starttimer(dp, ticks) 1043 struct dadq *dp; 1044 int ticks; 1045 { 1046 1047 callout_reset(&dp->dad_timer_ch, ticks, 1048 (void (*) __P((void *)))nd6_dad_timer, (void *)dp->dad_ifa); 1049 } 1050 1051 static void 1052 nd6_dad_stoptimer(dp) 1053 struct dadq *dp; 1054 { 1055 1056 callout_stop(&dp->dad_timer_ch); 1057 } 1058 1059 /* 1060 * Start Duplicated Address Detection (DAD) for specified interface address. 1061 */ 1062 void 1063 nd6_dad_start(ifa, tick) 1064 struct ifaddr *ifa; 1065 int *tick; /* minimum delay ticks for IFF_UP event */ 1066 { 1067 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1068 struct dadq *dp; 1069 1070 if (!dad_init) { 1071 TAILQ_INIT(&dadq); 1072 dad_init++; 1073 } 1074 1075 /* 1076 * If we don't need DAD, don't do it. 1077 * There are several cases: 1078 * - DAD is disabled (ip6_dad_count == 0) 1079 * - the interface address is anycast 1080 */ 1081 if (!(ia->ia6_flags & IN6_IFF_TENTATIVE)) { 1082 log(LOG_DEBUG, 1083 "nd6_dad_start: called with non-tentative address " 1084 "%s(%s)\n", 1085 ip6_sprintf(&ia->ia_addr.sin6_addr), 1086 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1087 return; 1088 } 1089 if (ia->ia6_flags & IN6_IFF_ANYCAST) { 1090 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1091 return; 1092 } 1093 if (!ip6_dad_count) { 1094 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1095 return; 1096 } 1097 if (!ifa->ifa_ifp) 1098 panic("nd6_dad_start: ifa->ifa_ifp == NULL"); 1099 if (!(ifa->ifa_ifp->if_flags & IFF_UP)) 1100 return; 1101 if (nd6_dad_find(ifa) != NULL) { 1102 /* DAD already in progress */ 1103 return; 1104 } 1105 1106 dp = malloc(sizeof(*dp), M_IP6NDP, M_NOWAIT); 1107 if (dp == NULL) { 1108 log(LOG_ERR, "nd6_dad_start: memory allocation failed for " 1109 "%s(%s)\n", 1110 ip6_sprintf(&ia->ia_addr.sin6_addr), 1111 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1112 return; 1113 } 1114 bzero(dp, sizeof(*dp)); 1115 callout_init(&dp->dad_timer_ch); 1116 TAILQ_INSERT_TAIL(&dadq, (struct dadq *)dp, dad_list); 1117 1118 nd6log((LOG_DEBUG, "%s: starting DAD for %s\n", if_name(ifa->ifa_ifp), 1119 ip6_sprintf(&ia->ia_addr.sin6_addr))); 1120 1121 /* 1122 * Send NS packet for DAD, ip6_dad_count times. 1123 * Note that we must delay the first transmission, if this is the 1124 * first packet to be sent from the interface after interface 1125 * (re)initialization. 1126 */ 1127 dp->dad_ifa = ifa; 1128 IFAREF(ifa); /* just for safety */ 1129 dp->dad_count = ip6_dad_count; 1130 dp->dad_ns_icount = dp->dad_na_icount = 0; 1131 dp->dad_ns_ocount = dp->dad_ns_tcount = 0; 1132 if (tick == NULL) { 1133 nd6_dad_ns_output(dp, ifa); 1134 nd6_dad_starttimer(dp, 1135 ND6_RETRANS_SEC(ND_IFINFO(ifa->ifa_ifp)->retrans) * hz); 1136 } else { 1137 int ntick; 1138 1139 if (*tick == 0) 1140 ntick = arc4random() % (MAX_RTR_SOLICITATION_DELAY * hz); 1141 else 1142 ntick = *tick + arc4random() % (hz / 2); 1143 *tick = ntick; 1144 nd6_dad_starttimer(dp, ntick); 1145 } 1146 } 1147 1148 /* 1149 * terminate DAD unconditionally. used for address removals. 1150 */ 1151 void 1152 nd6_dad_stop(ifa) 1153 struct ifaddr *ifa; 1154 { 1155 struct dadq *dp; 1156 1157 if (!dad_init) 1158 return; 1159 dp = nd6_dad_find(ifa); 1160 if (!dp) { 1161 /* DAD wasn't started yet */ 1162 return; 1163 } 1164 1165 nd6_dad_stoptimer(dp); 1166 1167 TAILQ_REMOVE(&dadq, (struct dadq *)dp, dad_list); 1168 free(dp, M_IP6NDP); 1169 dp = NULL; 1170 IFAFREE(ifa); 1171 } 1172 1173 static void 1174 nd6_dad_timer(ifa) 1175 struct ifaddr *ifa; 1176 { 1177 int s; 1178 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1179 struct dadq *dp; 1180 1181 s = splsoftnet(); /* XXX */ 1182 1183 /* Sanity check */ 1184 if (ia == NULL) { 1185 log(LOG_ERR, "nd6_dad_timer: called with null parameter\n"); 1186 goto done; 1187 } 1188 dp = nd6_dad_find(ifa); 1189 if (dp == NULL) { 1190 log(LOG_ERR, "nd6_dad_timer: DAD structure not found\n"); 1191 goto done; 1192 } 1193 if (ia->ia6_flags & IN6_IFF_DUPLICATED) { 1194 log(LOG_ERR, "nd6_dad_timer: called with duplicated address " 1195 "%s(%s)\n", 1196 ip6_sprintf(&ia->ia_addr.sin6_addr), 1197 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1198 goto done; 1199 } 1200 if ((ia->ia6_flags & IN6_IFF_TENTATIVE) == 0) { 1201 log(LOG_ERR, "nd6_dad_timer: called with non-tentative address " 1202 "%s(%s)\n", 1203 ip6_sprintf(&ia->ia_addr.sin6_addr), 1204 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1205 goto done; 1206 } 1207 1208 /* timeouted with IFF_{RUNNING,UP} check */ 1209 if (dp->dad_ns_tcount > dad_maxtry) { 1210 nd6log((LOG_INFO, "%s: could not run DAD, driver problem?\n", 1211 if_name(ifa->ifa_ifp))); 1212 1213 TAILQ_REMOVE(&dadq, (struct dadq *)dp, dad_list); 1214 free(dp, M_IP6NDP); 1215 dp = NULL; 1216 IFAFREE(ifa); 1217 goto done; 1218 } 1219 1220 /* Need more checks? */ 1221 if (dp->dad_ns_ocount < dp->dad_count) { 1222 /* 1223 * We have more NS to go. Send NS packet for DAD. 1224 */ 1225 nd6_dad_ns_output(dp, ifa); 1226 nd6_dad_starttimer(dp, 1227 ND6_RETRANS_SEC(ND_IFINFO(ifa->ifa_ifp)->retrans) * hz); 1228 } else { 1229 /* 1230 * We have transmitted sufficient number of DAD packets. 1231 * See what we've got. 1232 */ 1233 int duplicate; 1234 1235 duplicate = 0; 1236 1237 if (dp->dad_na_icount) { 1238 /* 1239 * the check is in nd6_dad_na_input(), 1240 * but just in case 1241 */ 1242 duplicate++; 1243 } 1244 1245 if (dp->dad_ns_icount) { 1246 #if 0 /* heuristics */ 1247 /* 1248 * if 1249 * - we have sent many(?) DAD NS, and 1250 * - the number of NS we sent equals to the 1251 * number of NS we've got, and 1252 * - we've got no NA 1253 * we may have a faulty network card/driver which 1254 * loops back multicasts to myself. 1255 */ 1256 if (3 < dp->dad_count 1257 && dp->dad_ns_icount == dp->dad_count 1258 && dp->dad_na_icount == 0) { 1259 log(LOG_INFO, "DAD questionable for %s(%s): " 1260 "network card loops back multicast?\n", 1261 ip6_sprintf(&ia->ia_addr.sin6_addr), 1262 if_name(ifa->ifa_ifp)); 1263 /* XXX consider it a duplicate or not? */ 1264 /* duplicate++; */ 1265 } else { 1266 /* We've seen NS, means DAD has failed. */ 1267 duplicate++; 1268 } 1269 #else 1270 /* We've seen NS, means DAD has failed. */ 1271 duplicate++; 1272 #endif 1273 } 1274 1275 if (duplicate) { 1276 /* (*dp) will be freed in nd6_dad_duplicated() */ 1277 dp = NULL; 1278 nd6_dad_duplicated(ifa); 1279 } else { 1280 /* 1281 * We are done with DAD. No NA came, no NS came. 1282 * duplicated address found. 1283 */ 1284 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1285 1286 nd6log((LOG_DEBUG, 1287 "%s: DAD complete for %s - no duplicates found\n", 1288 if_name(ifa->ifa_ifp), 1289 ip6_sprintf(&ia->ia_addr.sin6_addr))); 1290 1291 TAILQ_REMOVE(&dadq, (struct dadq *)dp, dad_list); 1292 free(dp, M_IP6NDP); 1293 dp = NULL; 1294 IFAFREE(ifa); 1295 } 1296 } 1297 1298 done: 1299 splx(s); 1300 } 1301 1302 void 1303 nd6_dad_duplicated(ifa) 1304 struct ifaddr *ifa; 1305 { 1306 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1307 struct dadq *dp; 1308 1309 dp = nd6_dad_find(ifa); 1310 if (dp == NULL) { 1311 log(LOG_ERR, "nd6_dad_duplicated: DAD structure not found\n"); 1312 return; 1313 } 1314 1315 log(LOG_ERR, "%s: DAD detected duplicate IPv6 address %s: " 1316 "NS in/out=%d/%d, NA in=%d\n", 1317 if_name(ifa->ifa_ifp), ip6_sprintf(&ia->ia_addr.sin6_addr), 1318 dp->dad_ns_icount, dp->dad_ns_ocount, dp->dad_na_icount); 1319 1320 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1321 ia->ia6_flags |= IN6_IFF_DUPLICATED; 1322 1323 /* We are done with DAD, with duplicated address found. (failure) */ 1324 nd6_dad_stoptimer(dp); 1325 1326 log(LOG_ERR, "%s: DAD complete for %s - duplicate found\n", 1327 if_name(ifa->ifa_ifp), ip6_sprintf(&ia->ia_addr.sin6_addr)); 1328 log(LOG_ERR, "%s: manual intervention required\n", 1329 if_name(ifa->ifa_ifp)); 1330 1331 TAILQ_REMOVE(&dadq, (struct dadq *)dp, dad_list); 1332 free(dp, M_IP6NDP); 1333 dp = NULL; 1334 IFAFREE(ifa); 1335 } 1336 1337 static void 1338 nd6_dad_ns_output(dp, ifa) 1339 struct dadq *dp; 1340 struct ifaddr *ifa; 1341 { 1342 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1343 struct ifnet *ifp = ifa->ifa_ifp; 1344 1345 dp->dad_ns_tcount++; 1346 if ((ifp->if_flags & IFF_UP) == 0) { 1347 #if 0 1348 printf("%s: interface down?\n", if_name(ifp)); 1349 #endif 1350 return; 1351 } 1352 if ((ifp->if_flags & IFF_RUNNING) == 0) { 1353 #if 0 1354 printf("%s: interface not running?\n", if_name(ifp)); 1355 #endif 1356 return; 1357 } 1358 1359 dp->dad_ns_ocount++; 1360 nd6_ns_output(ifp, NULL, &ia->ia_addr.sin6_addr, NULL, 1); 1361 } 1362 1363 static void 1364 nd6_dad_ns_input(ifa) 1365 struct ifaddr *ifa; 1366 { 1367 struct in6_ifaddr *ia; 1368 struct ifnet *ifp; 1369 const struct in6_addr *taddr6; 1370 struct dadq *dp; 1371 int duplicate; 1372 1373 if (!ifa) 1374 panic("ifa == NULL in nd6_dad_ns_input"); 1375 1376 ia = (struct in6_ifaddr *)ifa; 1377 ifp = ifa->ifa_ifp; 1378 taddr6 = &ia->ia_addr.sin6_addr; 1379 duplicate = 0; 1380 dp = nd6_dad_find(ifa); 1381 1382 /* Quickhack - completely ignore DAD NS packets */ 1383 if (dad_ignore_ns) { 1384 nd6log((LOG_INFO, 1385 "nd6_dad_ns_input: ignoring DAD NS packet for " 1386 "address %s(%s)\n", ip6_sprintf(taddr6), 1387 if_name(ifa->ifa_ifp))); 1388 return; 1389 } 1390 1391 /* 1392 * if I'm yet to start DAD, someone else started using this address 1393 * first. I have a duplicate and you win. 1394 */ 1395 if (!dp || dp->dad_ns_ocount == 0) 1396 duplicate++; 1397 1398 /* XXX more checks for loopback situation - see nd6_dad_timer too */ 1399 1400 if (duplicate) { 1401 dp = NULL; /* will be freed in nd6_dad_duplicated() */ 1402 nd6_dad_duplicated(ifa); 1403 } else { 1404 /* 1405 * not sure if I got a duplicate. 1406 * increment ns count and see what happens. 1407 */ 1408 if (dp) 1409 dp->dad_ns_icount++; 1410 } 1411 } 1412 1413 static void 1414 nd6_dad_na_input(ifa) 1415 struct ifaddr *ifa; 1416 { 1417 struct dadq *dp; 1418 1419 if (!ifa) 1420 panic("ifa == NULL in nd6_dad_na_input"); 1421 1422 dp = nd6_dad_find(ifa); 1423 if (dp) 1424 dp->dad_na_icount++; 1425 1426 /* remove the address. */ 1427 nd6_dad_duplicated(ifa); 1428 } 1429
Indexes created Mon Sep 29 21:09:56 GMT 2025