nd6_nbr.c revision 1.34.6.1
1 /* $NetBSD: nd6_nbr.c,v 1.34.6.1 2003/10/02 20:30:08 tron 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 1.34.6.1 2003/10/02 20:30:08 tron 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 #include <netinet6/in6_pcb.h> 66 67 #ifdef IPSEC 68 #include <netinet6/ipsec.h> 69 #endif 70 71 #include <net/net_osdep.h> 72 73 #define SDL(s) ((struct sockaddr_dl *)s) 74 75 struct dadq; 76 static struct dadq *nd6_dad_find __P((struct ifaddr *)); 77 static void nd6_dad_starttimer __P((struct dadq *, int)); 78 static void nd6_dad_stoptimer __P((struct dadq *)); 79 static void nd6_dad_timer __P((struct ifaddr *)); 80 static void nd6_dad_ns_output __P((struct dadq *, struct ifaddr *)); 81 static void nd6_dad_ns_input __P((struct ifaddr *)); 82 static void nd6_dad_na_input __P((struct ifaddr *)); 83 84 static int dad_ignore_ns = 0; /* ignore NS in DAD - specwise incorrect*/ 85 static int dad_maxtry = 15; /* max # of *tries* to transmit DAD packet */ 86 87 /* 88 * Input an Neighbor Solicitation Message. 89 * 90 * Based on RFC 2461 91 * Based on RFC 2462 (duplicated address detection) 92 */ 93 void 94 nd6_ns_input(m, off, icmp6len) 95 struct mbuf *m; 96 int off, icmp6len; 97 { 98 struct ifnet *ifp = m->m_pkthdr.rcvif; 99 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 100 struct nd_neighbor_solicit *nd_ns; 101 struct in6_addr saddr6 = ip6->ip6_src; 102 struct in6_addr daddr6 = ip6->ip6_dst; 103 struct in6_addr taddr6; 104 struct in6_addr myaddr6; 105 char *lladdr = NULL; 106 struct ifaddr *ifa; 107 int lladdrlen = 0; 108 int anycast = 0, proxy = 0, tentative = 0; 109 int router = ip6_forwarding; 110 int tlladdr; 111 union nd_opts ndopts; 112 struct sockaddr_dl *proxydl = NULL; 113 114 #ifndef PULLDOWN_TEST 115 IP6_EXTHDR_CHECK(m, off, icmp6len,); 116 nd_ns = (struct nd_neighbor_solicit *)((caddr_t)ip6 + off); 117 #else 118 IP6_EXTHDR_GET(nd_ns, struct nd_neighbor_solicit *, m, off, icmp6len); 119 if (nd_ns == NULL) { 120 icmp6stat.icp6s_tooshort++; 121 return; 122 } 123 #endif 124 ip6 = mtod(m, struct ip6_hdr *); /* adjust pointer for safety */ 125 taddr6 = nd_ns->nd_ns_target; 126 127 if (ip6->ip6_hlim != 255) { 128 nd6log((LOG_ERR, 129 "nd6_ns_input: invalid hlim (%d) from %s to %s on %s\n", 130 ip6->ip6_hlim, ip6_sprintf(&ip6->ip6_src), 131 ip6_sprintf(&ip6->ip6_dst), if_name(ifp))); 132 goto bad; 133 } 134 135 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) { 136 /* dst has to be solicited node multicast address. */ 137 /* don't check ifindex portion */ 138 if (daddr6.s6_addr16[0] == IPV6_ADDR_INT16_MLL && 139 daddr6.s6_addr32[1] == 0 && 140 daddr6.s6_addr32[2] == IPV6_ADDR_INT32_ONE && 141 daddr6.s6_addr8[12] == 0xff) { 142 ; /* good */ 143 } else { 144 nd6log((LOG_INFO, "nd6_ns_input: bad DAD packet " 145 "(wrong ip6 dst)\n")); 146 goto bad; 147 } 148 } 149 150 if (IN6_IS_ADDR_MULTICAST(&taddr6)) { 151 nd6log((LOG_INFO, "nd6_ns_input: bad NS target (multicast)\n")); 152 goto bad; 153 } 154 155 if (IN6_IS_SCOPE_LINKLOCAL(&taddr6)) 156 taddr6.s6_addr16[1] = htons(ifp->if_index); 157 158 icmp6len -= sizeof(*nd_ns); 159 nd6_option_init(nd_ns + 1, icmp6len, &ndopts); 160 if (nd6_options(&ndopts) < 0) { 161 nd6log((LOG_INFO, 162 "nd6_ns_input: invalid ND option, ignored\n")); 163 /* nd6_options have incremented stats */ 164 goto freeit; 165 } 166 167 if (ndopts.nd_opts_src_lladdr) { 168 lladdr = (char *)(ndopts.nd_opts_src_lladdr + 1); 169 lladdrlen = ndopts.nd_opts_src_lladdr->nd_opt_len << 3; 170 } 171 172 if (IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_src) && lladdr) { 173 nd6log((LOG_INFO, "nd6_ns_input: bad DAD packet " 174 "(link-layer address option)\n")); 175 goto bad; 176 } 177 178 /* 179 * Attaching target link-layer address to the NA? 180 * (RFC 2461 7.2.4) 181 * 182 * NS IP dst is unicast/anycast MUST NOT add 183 * NS IP dst is solicited-node multicast MUST add 184 * 185 * In implementation, we add target link-layer address by default. 186 * We do not add one in MUST NOT cases. 187 */ 188 #if 0 /* too much! */ 189 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &daddr6); 190 if (ifa && (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_ANYCAST)) 191 tlladdr = 0; 192 else 193 #endif 194 if (!IN6_IS_ADDR_MULTICAST(&daddr6)) 195 tlladdr = 0; 196 else 197 tlladdr = 1; 198 199 /* 200 * Target address (taddr6) must be either: 201 * (1) Valid unicast/anycast address for my receiving interface, 202 * (2) Unicast address for which I'm offering proxy service, or 203 * (3) "tentative" address on which DAD is being performed. 204 */ 205 /* (1) and (3) check. */ 206 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &taddr6); 207 208 /* (2) check. */ 209 if (!ifa) { 210 struct rtentry *rt; 211 struct sockaddr_in6 tsin6; 212 213 bzero(&tsin6, sizeof tsin6); 214 tsin6.sin6_len = sizeof(struct sockaddr_in6); 215 tsin6.sin6_family = AF_INET6; 216 tsin6.sin6_addr = taddr6; 217 218 rt = rtalloc1((struct sockaddr *)&tsin6, 0); 219 if (rt && (rt->rt_flags & RTF_ANNOUNCE) != 0 && 220 rt->rt_gateway->sa_family == AF_LINK) { 221 /* 222 * proxy NDP for single entry 223 */ 224 ifa = (struct ifaddr *)in6ifa_ifpforlinklocal(ifp, 225 IN6_IFF_NOTREADY|IN6_IFF_ANYCAST); 226 if (ifa) { 227 proxy = 1; 228 proxydl = SDL(rt->rt_gateway); 229 router = 0; /* XXX */ 230 } 231 } 232 if (rt) 233 rtfree(rt); 234 } 235 if (!ifa) { 236 /* 237 * We've got an NS packet, and we don't have that adddress 238 * assigned for us. We MUST silently ignore it. 239 * See RFC2461 7.2.3. 240 */ 241 goto freeit; 242 } 243 myaddr6 = *IFA_IN6(ifa); 244 anycast = ((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_ANYCAST; 245 tentative = ((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_TENTATIVE; 246 if (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_DUPLICATED) 247 goto freeit; 248 249 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) { 250 nd6log((LOG_INFO, "nd6_ns_input: lladdrlen mismatch for %s " 251 "(if %d, NS packet %d)\n", 252 ip6_sprintf(&taddr6), ifp->if_addrlen, lladdrlen - 2)); 253 goto bad; 254 } 255 256 if (IN6_ARE_ADDR_EQUAL(&myaddr6, &saddr6)) { 257 nd6log((LOG_INFO, "nd6_ns_input: duplicate IP6 address %s\n", 258 ip6_sprintf(&saddr6))); 259 goto freeit; 260 } 261 262 /* 263 * We have neighbor solicitation packet, with target address equals to 264 * one of my tentative address. 265 * 266 * src addr how to process? 267 * --- --- 268 * multicast of course, invalid (rejected in ip6_input) 269 * unicast somebody is doing address resolution -> ignore 270 * unspec dup address detection 271 * 272 * The processing is defined in RFC 2462. 273 */ 274 if (tentative) { 275 /* 276 * If source address is unspecified address, it is for 277 * duplicated address detection. 278 * 279 * If not, the packet is for addess resolution; 280 * silently ignore it. 281 */ 282 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) 283 nd6_dad_ns_input(ifa); 284 285 goto freeit; 286 } 287 288 /* 289 * If the source address is unspecified address, entries must not 290 * be created or updated. 291 * It looks that sender is performing DAD. Output NA toward 292 * all-node multicast address, to tell the sender that I'm using 293 * the address. 294 * S bit ("solicited") must be zero. 295 */ 296 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) { 297 saddr6 = in6addr_linklocal_allnodes; 298 saddr6.s6_addr16[1] = htons(ifp->if_index); 299 nd6_na_output(ifp, &saddr6, &taddr6, 300 ((anycast || proxy || !tlladdr) ? 0 : ND_NA_FLAG_OVERRIDE) | 301 (router ? ND_NA_FLAG_ROUTER : 0), 302 tlladdr, (struct sockaddr *)proxydl); 303 goto freeit; 304 } 305 306 nd6_cache_lladdr(ifp, &saddr6, lladdr, lladdrlen, ND_NEIGHBOR_SOLICIT, 0); 307 308 nd6_na_output(ifp, &saddr6, &taddr6, 309 ((anycast || proxy || !tlladdr) ? 0 : ND_NA_FLAG_OVERRIDE) | 310 (router ? ND_NA_FLAG_ROUTER : 0) | ND_NA_FLAG_SOLICITED, 311 tlladdr, (struct sockaddr *)proxydl); 312 freeit: 313 m_freem(m); 314 return; 315 316 bad: 317 nd6log((LOG_ERR, "nd6_ns_input: src=%s\n", ip6_sprintf(&saddr6))); 318 nd6log((LOG_ERR, "nd6_ns_input: dst=%s\n", ip6_sprintf(&daddr6))); 319 nd6log((LOG_ERR, "nd6_ns_input: tgt=%s\n", ip6_sprintf(&taddr6))); 320 icmp6stat.icp6s_badns++; 321 m_freem(m); 322 } 323 324 /* 325 * Output an Neighbor Solicitation Message. Caller specifies: 326 * - ICMP6 header source IP6 address 327 * - ND6 header target IP6 address 328 * - ND6 header source datalink address 329 * 330 * Based on RFC 2461 331 * Based on RFC 2462 (duplicated address detection) 332 */ 333 void 334 nd6_ns_output(ifp, daddr6, taddr6, ln, dad) 335 struct ifnet *ifp; 336 const struct in6_addr *daddr6, *taddr6; 337 struct llinfo_nd6 *ln; /* for source address determination */ 338 int dad; /* duplicated address detection */ 339 { 340 struct mbuf *m; 341 struct ip6_hdr *ip6; 342 struct nd_neighbor_solicit *nd_ns; 343 struct sockaddr_in6 src_sa, dst_sa; 344 struct ip6_moptions im6o; 345 int icmp6len; 346 int maxlen; 347 caddr_t mac; 348 struct route_in6 ro; 349 350 bzero(&ro, sizeof(ro)); 351 352 if (IN6_IS_ADDR_MULTICAST(taddr6)) 353 return; 354 355 /* estimate the size of message */ 356 maxlen = sizeof(*ip6) + sizeof(*nd_ns); 357 maxlen += (sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7; 358 #ifdef DIAGNOSTIC 359 if (max_linkhdr + maxlen >= MCLBYTES) { 360 printf("nd6_ns_output: max_linkhdr + maxlen >= MCLBYTES " 361 "(%d + %d > %d)\n", max_linkhdr, maxlen, MCLBYTES); 362 panic("nd6_ns_output: insufficient MCLBYTES"); 363 /* NOTREACHED */ 364 } 365 #endif 366 367 MGETHDR(m, M_DONTWAIT, MT_DATA); 368 if (m && max_linkhdr + maxlen >= MHLEN) { 369 MCLGET(m, M_DONTWAIT); 370 if ((m->m_flags & M_EXT) == 0) { 371 m_free(m); 372 m = NULL; 373 } 374 } 375 if (m == NULL) 376 return; 377 m->m_pkthdr.rcvif = NULL; 378 379 if (daddr6 == NULL || IN6_IS_ADDR_MULTICAST(daddr6)) { 380 m->m_flags |= M_MCAST; 381 im6o.im6o_multicast_ifp = ifp; 382 im6o.im6o_multicast_hlim = 255; 383 im6o.im6o_multicast_loop = 0; 384 } 385 386 icmp6len = sizeof(*nd_ns); 387 m->m_pkthdr.len = m->m_len = sizeof(*ip6) + icmp6len; 388 m->m_data += max_linkhdr; /* or MH_ALIGN() equivalent? */ 389 390 /* fill neighbor solicitation packet */ 391 ip6 = mtod(m, struct ip6_hdr *); 392 ip6->ip6_flow = 0; 393 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 394 ip6->ip6_vfc |= IPV6_VERSION; 395 /* ip6->ip6_plen will be set later */ 396 ip6->ip6_nxt = IPPROTO_ICMPV6; 397 ip6->ip6_hlim = 255; 398 /* determine the source and destination addresses */ 399 bzero(&src_sa, sizeof(src_sa)); 400 bzero(&dst_sa, sizeof(dst_sa)); 401 src_sa.sin6_family = dst_sa.sin6_family = AF_INET6; 402 src_sa.sin6_len = dst_sa.sin6_len = sizeof(struct sockaddr_in6); 403 if (daddr6) 404 dst_sa.sin6_addr = *daddr6; 405 else { 406 dst_sa.sin6_addr.s6_addr16[0] = IPV6_ADDR_INT16_MLL; 407 dst_sa.sin6_addr.s6_addr16[1] = htons(ifp->if_index); 408 dst_sa.sin6_addr.s6_addr32[1] = 0; 409 dst_sa.sin6_addr.s6_addr32[2] = IPV6_ADDR_INT32_ONE; 410 dst_sa.sin6_addr.s6_addr32[3] = taddr6->s6_addr32[3]; 411 dst_sa.sin6_addr.s6_addr8[12] = 0xff; 412 } 413 ip6->ip6_dst = dst_sa.sin6_addr; 414 if (!dad) { 415 /* 416 * RFC2461 7.2.2: 417 * "If the source address of the packet prompting the 418 * solicitation is the same as one of the addresses assigned 419 * to the outgoing interface, that address SHOULD be placed 420 * in the IP Source Address of the outgoing solicitation. 421 * Otherwise, any one of the addresses assigned to the 422 * interface should be used." 423 * 424 * We use the source address for the prompting packet 425 * (saddr6), if: 426 * - saddr6 is given from the caller (by giving "ln"), and 427 * - saddr6 belongs to the outgoing interface. 428 * Otherwise, we perform the source address selection as usual. 429 */ 430 struct ip6_hdr *hip6; /* hold ip6 */ 431 struct in6_addr *saddr6; 432 433 if (ln && ln->ln_hold) { 434 hip6 = mtod(ln->ln_hold, struct ip6_hdr *); 435 /* XXX pullup? */ 436 if (sizeof(*hip6) < ln->ln_hold->m_len) 437 saddr6 = &hip6->ip6_src; 438 else 439 saddr6 = NULL; 440 } else 441 saddr6 = NULL; 442 if (saddr6 && in6ifa_ifpwithaddr(ifp, saddr6)) 443 src_sa.sin6_addr = *saddr6; 444 else { 445 struct in6_addr *src0; 446 int error; 447 448 bcopy(&dst_sa, &ro.ro_dst, sizeof(dst_sa)); 449 src0 = in6_selectsrc(&dst_sa, NULL, NULL, &ro, NULL, 450 &error); 451 if (src0 == NULL) { 452 nd6log((LOG_DEBUG, 453 "nd6_ns_output: source can't be " 454 "determined: dst=%s, error=%d\n", 455 ip6_sprintf(&dst_sa.sin6_addr), error)); 456 goto bad; 457 } 458 src_sa.sin6_addr = *src0; 459 } 460 } else { 461 /* 462 * Source address for DAD packet must always be IPv6 463 * unspecified address. (0::0) 464 * We actually don't have to 0-clear the address (we did it 465 * above), but we do so here explicitly to make the intention 466 * clearer. 467 */ 468 bzero(&src_sa.sin6_addr, sizeof(src_sa.sin6_addr)); 469 } 470 ip6->ip6_src = src_sa.sin6_addr; 471 nd_ns = (struct nd_neighbor_solicit *)(ip6 + 1); 472 nd_ns->nd_ns_type = ND_NEIGHBOR_SOLICIT; 473 nd_ns->nd_ns_code = 0; 474 nd_ns->nd_ns_reserved = 0; 475 nd_ns->nd_ns_target = *taddr6; 476 477 if (IN6_IS_SCOPE_LINKLOCAL(&nd_ns->nd_ns_target)) 478 nd_ns->nd_ns_target.s6_addr16[1] = 0; 479 480 /* 481 * Add source link-layer address option. 482 * 483 * spec implementation 484 * --- --- 485 * DAD packet MUST NOT do not add the option 486 * there's no link layer address: 487 * impossible do not add the option 488 * there's link layer address: 489 * Multicast NS MUST add one add the option 490 * Unicast NS SHOULD add one add the option 491 */ 492 if (!dad && (mac = nd6_ifptomac(ifp))) { 493 int optlen = sizeof(struct nd_opt_hdr) + ifp->if_addrlen; 494 struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)(nd_ns + 1); 495 /* 8 byte alignments... */ 496 optlen = (optlen + 7) & ~7; 497 498 m->m_pkthdr.len += optlen; 499 m->m_len += optlen; 500 icmp6len += optlen; 501 bzero((caddr_t)nd_opt, optlen); 502 nd_opt->nd_opt_type = ND_OPT_SOURCE_LINKADDR; 503 nd_opt->nd_opt_len = optlen >> 3; 504 bcopy(mac, (caddr_t)(nd_opt + 1), ifp->if_addrlen); 505 } 506 507 ip6->ip6_plen = htons((u_short)icmp6len); 508 nd_ns->nd_ns_cksum = 0; 509 nd_ns->nd_ns_cksum = 510 in6_cksum(m, IPPROTO_ICMPV6, sizeof(*ip6), icmp6len); 511 512 #ifdef IPSEC 513 /* Don't lookup socket */ 514 (void)ipsec_setsocket(m, NULL); 515 #endif 516 ip6_output(m, NULL, &ro, dad ? IPV6_UNSPECSRC : 0, &im6o, NULL); 517 icmp6_ifstat_inc(ifp, ifs6_out_msg); 518 icmp6_ifstat_inc(ifp, ifs6_out_neighborsolicit); 519 icmp6stat.icp6s_outhist[ND_NEIGHBOR_SOLICIT]++; 520 521 if (ro.ro_rt) { /* we don't cache this route. */ 522 RTFREE(ro.ro_rt); 523 } 524 return; 525 526 bad: 527 if (ro.ro_rt) { 528 RTFREE(ro.ro_rt); 529 } 530 m_freem(m); 531 return; 532 } 533 534 /* 535 * Neighbor advertisement input handling. 536 * 537 * Based on RFC 2461 538 long time_second = time.tv_sec; 539 * Based on RFC 2462 (duplicated address detection) 540 * 541 * the following items are not implemented yet: 542 * - proxy advertisement delay rule (RFC2461 7.2.8, last paragraph, SHOULD) 543 * - anycast advertisement delay rule (RFC2461 7.2.7, SHOULD) 544 */ 545 void 546 nd6_na_input(m, off, icmp6len) 547 struct mbuf *m; 548 int off, icmp6len; 549 { 550 struct ifnet *ifp = m->m_pkthdr.rcvif; 551 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 552 struct nd_neighbor_advert *nd_na; 553 #if 0 554 struct in6_addr saddr6 = ip6->ip6_src; 555 #endif 556 struct in6_addr daddr6 = ip6->ip6_dst; 557 struct in6_addr taddr6; 558 int flags; 559 int is_router; 560 int is_solicited; 561 int is_override; 562 char *lladdr = NULL; 563 int lladdrlen = 0; 564 struct ifaddr *ifa; 565 struct llinfo_nd6 *ln; 566 struct rtentry *rt; 567 struct sockaddr_dl *sdl; 568 union nd_opts ndopts; 569 long time_second = time.tv_sec; 570 571 if (ip6->ip6_hlim != 255) { 572 nd6log((LOG_ERR, 573 "nd6_na_input: invalid hlim (%d) from %s to %s on %s\n", 574 ip6->ip6_hlim, ip6_sprintf(&ip6->ip6_src), 575 ip6_sprintf(&ip6->ip6_dst), if_name(ifp))); 576 goto bad; 577 } 578 579 #ifndef PULLDOWN_TEST 580 IP6_EXTHDR_CHECK(m, off, icmp6len,); 581 nd_na = (struct nd_neighbor_advert *)((caddr_t)ip6 + off); 582 #else 583 IP6_EXTHDR_GET(nd_na, struct nd_neighbor_advert *, m, off, icmp6len); 584 if (nd_na == NULL) { 585 icmp6stat.icp6s_tooshort++; 586 return; 587 } 588 #endif 589 taddr6 = nd_na->nd_na_target; 590 flags = nd_na->nd_na_flags_reserved; 591 is_router = ((flags & ND_NA_FLAG_ROUTER) != 0); 592 is_solicited = ((flags & ND_NA_FLAG_SOLICITED) != 0); 593 is_override = ((flags & ND_NA_FLAG_OVERRIDE) != 0); 594 595 if (IN6_IS_SCOPE_LINKLOCAL(&taddr6)) 596 taddr6.s6_addr16[1] = htons(ifp->if_index); 597 598 if (IN6_IS_ADDR_MULTICAST(&taddr6)) { 599 nd6log((LOG_ERR, 600 "nd6_na_input: invalid target address %s\n", 601 ip6_sprintf(&taddr6))); 602 goto bad; 603 } 604 if (is_solicited && IN6_IS_ADDR_MULTICAST(&daddr6)) { 605 nd6log((LOG_ERR, 606 "nd6_na_input: a solicited adv is multicasted\n")); 607 goto bad; 608 } 609 610 icmp6len -= sizeof(*nd_na); 611 nd6_option_init(nd_na + 1, icmp6len, &ndopts); 612 if (nd6_options(&ndopts) < 0) { 613 nd6log((LOG_INFO, 614 "nd6_na_input: invalid ND option, ignored\n")); 615 /* nd6_options have incremented stats */ 616 goto freeit; 617 } 618 619 if (ndopts.nd_opts_tgt_lladdr) { 620 lladdr = (char *)(ndopts.nd_opts_tgt_lladdr + 1); 621 lladdrlen = ndopts.nd_opts_tgt_lladdr->nd_opt_len << 3; 622 } 623 624 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &taddr6); 625 626 /* 627 * Target address matches one of my interface address. 628 * 629 * If my address is tentative, this means that there's somebody 630 * already using the same address as mine. This indicates DAD failure. 631 * This is defined in RFC 2462. 632 * 633 * Otherwise, process as defined in RFC 2461. 634 */ 635 if (ifa 636 && (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_TENTATIVE)) { 637 nd6_dad_na_input(ifa); 638 goto freeit; 639 } 640 641 /* Just for safety, maybe unnecessary. */ 642 if (ifa) { 643 log(LOG_ERR, 644 "nd6_na_input: duplicate IP6 address %s\n", 645 ip6_sprintf(&taddr6)); 646 goto freeit; 647 } 648 649 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) { 650 nd6log((LOG_INFO, "nd6_na_input: lladdrlen mismatch for %s " 651 "(if %d, NA packet %d)\n", ip6_sprintf(&taddr6), 652 ifp->if_addrlen, lladdrlen - 2)); 653 goto bad; 654 } 655 656 /* 657 * If no neighbor cache entry is found, NA SHOULD silently be 658 * discarded. 659 */ 660 rt = nd6_lookup(&taddr6, 0, ifp); 661 if ((rt == NULL) || 662 ((ln = (struct llinfo_nd6 *)rt->rt_llinfo) == NULL) || 663 ((sdl = SDL(rt->rt_gateway)) == NULL)) 664 goto freeit; 665 666 if (ln->ln_state == ND6_LLINFO_INCOMPLETE) { 667 /* 668 * If the link-layer has address, and no lladdr option came, 669 * discard the packet. 670 */ 671 if (ifp->if_addrlen && !lladdr) 672 goto freeit; 673 674 /* 675 * Record link-layer address, and update the state. 676 */ 677 sdl->sdl_alen = ifp->if_addrlen; 678 bcopy(lladdr, LLADDR(sdl), ifp->if_addrlen); 679 if (is_solicited) { 680 ln->ln_state = ND6_LLINFO_REACHABLE; 681 ln->ln_byhint = 0; 682 if (ln->ln_expire) 683 ln->ln_expire = time_second + 684 nd_ifinfo[rt->rt_ifp->if_index].reachable; 685 } else { 686 ln->ln_state = ND6_LLINFO_STALE; 687 ln->ln_expire = time_second + nd6_gctimer; 688 } 689 if ((ln->ln_router = is_router) != 0) { 690 /* 691 * This means a router's state has changed from 692 * non-reachable to probably reachable, and might 693 * affect the status of associated prefixes.. 694 */ 695 pfxlist_onlink_check(); 696 } 697 } else { 698 int llchange; 699 700 /* 701 * Check if the link-layer address has changed or not. 702 */ 703 if (!lladdr) 704 llchange = 0; 705 else { 706 if (sdl->sdl_alen) { 707 if (bcmp(lladdr, LLADDR(sdl), ifp->if_addrlen)) 708 llchange = 1; 709 else 710 llchange = 0; 711 } else 712 llchange = 1; 713 } 714 715 /* 716 * This is VERY complex. Look at it with care. 717 * 718 * override solicit lladdr llchange action 719 * (L: record lladdr) 720 * 721 * 0 0 n -- (2c) 722 * 0 0 y n (2b) L 723 * 0 0 y y (1) REACHABLE->STALE 724 * 0 1 n -- (2c) *->REACHABLE 725 * 0 1 y n (2b) L *->REACHABLE 726 * 0 1 y y (1) REACHABLE->STALE 727 * 1 0 n -- (2a) 728 * 1 0 y n (2a) L 729 * 1 0 y y (2a) L *->STALE 730 * 1 1 n -- (2a) *->REACHABLE 731 * 1 1 y n (2a) L *->REACHABLE 732 * 1 1 y y (2a) L *->REACHABLE 733 */ 734 if (!is_override && (lladdr && llchange)) { /* (1) */ 735 /* 736 * If state is REACHABLE, make it STALE. 737 * no other updates should be done. 738 */ 739 if (ln->ln_state == ND6_LLINFO_REACHABLE) { 740 ln->ln_state = ND6_LLINFO_STALE; 741 ln->ln_expire = time_second + nd6_gctimer; 742 } 743 goto freeit; 744 } else if (is_override /* (2a) */ 745 || (!is_override && (lladdr && !llchange)) /* (2b) */ 746 || !lladdr) { /* (2c) */ 747 /* 748 * Update link-local address, if any. 749 */ 750 if (lladdr) { 751 sdl->sdl_alen = ifp->if_addrlen; 752 bcopy(lladdr, LLADDR(sdl), ifp->if_addrlen); 753 } 754 755 /* 756 * If solicited, make the state REACHABLE. 757 * If not solicited and the link-layer address was 758 * changed, make it STALE. 759 */ 760 if (is_solicited) { 761 ln->ln_state = ND6_LLINFO_REACHABLE; 762 ln->ln_byhint = 0; 763 if (ln->ln_expire) { 764 ln->ln_expire = time_second + 765 nd_ifinfo[ifp->if_index].reachable; 766 } 767 } else { 768 if (lladdr && llchange) { 769 ln->ln_state = ND6_LLINFO_STALE; 770 ln->ln_expire = time_second + nd6_gctimer; 771 } 772 } 773 } 774 775 if (ln->ln_router && !is_router) { 776 /* 777 * The peer dropped the router flag. 778 * Remove the sender from the Default Router List and 779 * update the Destination Cache entries. 780 */ 781 struct nd_defrouter *dr; 782 struct in6_addr *in6; 783 int s; 784 785 in6 = &((struct sockaddr_in6 *)rt_key(rt))->sin6_addr; 786 787 /* 788 * Lock to protect the default router list. 789 * XXX: this might be unnecessary, since this function 790 * is only called under the network software interrupt 791 * context. However, we keep it just for safety. 792 */ 793 s = splsoftnet(); 794 dr = defrouter_lookup(in6, rt->rt_ifp); 795 if (dr) 796 defrtrlist_del(dr); 797 else if (!ip6_forwarding && ip6_accept_rtadv) { 798 /* 799 * Even if the neighbor is not in the default 800 * router list, the neighbor may be used 801 * as a next hop for some destinations 802 * (e.g. redirect case). So we must 803 * call rt6_flush explicitly. 804 */ 805 rt6_flush(&ip6->ip6_src, rt->rt_ifp); 806 } 807 splx(s); 808 } 809 ln->ln_router = is_router; 810 } 811 rt->rt_flags &= ~RTF_REJECT; 812 ln->ln_asked = 0; 813 if (ln->ln_hold) { 814 /* 815 * we assume ifp is not a loopback here, so just set the 2nd 816 * argument as the 1st one. 817 */ 818 nd6_output(ifp, ifp, ln->ln_hold, 819 (struct sockaddr_in6 *)rt_key(rt), rt); 820 ln->ln_hold = NULL; 821 } 822 823 freeit: 824 m_freem(m); 825 return; 826 827 bad: 828 icmp6stat.icp6s_badna++; 829 m_freem(m); 830 } 831 832 /* 833 * Neighbor advertisement output handling. 834 * 835 * Based on RFC 2461 836 * 837 * the following items are not implemented yet: 838 * - proxy advertisement delay rule (RFC2461 7.2.8, last paragraph, SHOULD) 839 * - anycast advertisement delay rule (RFC2461 7.2.7, SHOULD) 840 */ 841 void 842 nd6_na_output(ifp, daddr6, taddr6, flags, tlladdr, sdl0) 843 struct ifnet *ifp; 844 const struct in6_addr *daddr6, *taddr6; 845 u_long flags; 846 int tlladdr; /* 1 if include target link-layer address */ 847 struct sockaddr *sdl0; /* sockaddr_dl (= proxy NA) or NULL */ 848 { 849 struct mbuf *m; 850 struct ip6_hdr *ip6; 851 struct nd_neighbor_advert *nd_na; 852 struct ip6_moptions im6o; 853 struct sockaddr_in6 src_sa, dst_sa; 854 struct in6_addr *src0; 855 int icmp6len, maxlen, error; 856 caddr_t mac; 857 struct route_in6 ro; 858 859 mac = NULL; 860 bzero(&ro, sizeof(ro)); 861 862 /* estimate the size of message */ 863 maxlen = sizeof(*ip6) + sizeof(*nd_na); 864 maxlen += (sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7; 865 #ifdef DIAGNOSTIC 866 if (max_linkhdr + maxlen >= MCLBYTES) { 867 printf("nd6_na_output: max_linkhdr + maxlen >= MCLBYTES " 868 "(%d + %d > %d)\n", max_linkhdr, maxlen, MCLBYTES); 869 panic("nd6_na_output: insufficient MCLBYTES"); 870 /* NOTREACHED */ 871 } 872 #endif 873 874 MGETHDR(m, M_DONTWAIT, MT_DATA); 875 if (m && max_linkhdr + maxlen >= MHLEN) { 876 MCLGET(m, M_DONTWAIT); 877 if ((m->m_flags & M_EXT) == 0) { 878 m_free(m); 879 m = NULL; 880 } 881 } 882 if (m == NULL) 883 return; 884 m->m_pkthdr.rcvif = NULL; 885 886 if (IN6_IS_ADDR_MULTICAST(daddr6)) { 887 m->m_flags |= M_MCAST; 888 im6o.im6o_multicast_ifp = ifp; 889 im6o.im6o_multicast_hlim = 255; 890 im6o.im6o_multicast_loop = 0; 891 } 892 893 icmp6len = sizeof(*nd_na); 894 m->m_pkthdr.len = m->m_len = sizeof(struct ip6_hdr) + icmp6len; 895 m->m_data += max_linkhdr; /* or MH_ALIGN() equivalent? */ 896 897 /* fill neighbor advertisement packet */ 898 ip6 = mtod(m, struct ip6_hdr *); 899 ip6->ip6_flow = 0; 900 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 901 ip6->ip6_vfc |= IPV6_VERSION; 902 ip6->ip6_nxt = IPPROTO_ICMPV6; 903 ip6->ip6_hlim = 255; 904 bzero(&src_sa, sizeof(src_sa)); 905 bzero(&dst_sa, sizeof(dst_sa)); 906 src_sa.sin6_len = dst_sa.sin6_len = sizeof(struct sockaddr_in6); 907 src_sa.sin6_family = dst_sa.sin6_family = AF_INET6; 908 dst_sa.sin6_addr = *daddr6; 909 if (IN6_IS_ADDR_UNSPECIFIED(daddr6)) { 910 /* reply to DAD */ 911 dst_sa.sin6_addr.s6_addr16[0] = IPV6_ADDR_INT16_MLL; 912 dst_sa.sin6_addr.s6_addr16[1] = htons(ifp->if_index); 913 dst_sa.sin6_addr.s6_addr32[1] = 0; 914 dst_sa.sin6_addr.s6_addr32[2] = 0; 915 dst_sa.sin6_addr.s6_addr32[3] = IPV6_ADDR_INT32_ONE; 916 917 flags &= ~ND_NA_FLAG_SOLICITED; 918 } 919 ip6->ip6_dst = dst_sa.sin6_addr; 920 921 /* 922 * Select a source whose scope is the same as that of the dest. 923 */ 924 bcopy(&dst_sa, &ro.ro_dst, sizeof(dst_sa)); 925 src0 = in6_selectsrc(&dst_sa, NULL, NULL, &ro, NULL, &error); 926 if (src0 == NULL) { 927 nd6log((LOG_DEBUG, "nd6_na_output: source can't be " 928 "determined: dst=%s, error=%d\n", 929 ip6_sprintf(&dst_sa.sin6_addr), error)); 930 goto bad; 931 } 932 src_sa.sin6_addr = *src0; 933 ip6->ip6_src = src_sa.sin6_addr; 934 nd_na = (struct nd_neighbor_advert *)(ip6 + 1); 935 nd_na->nd_na_type = ND_NEIGHBOR_ADVERT; 936 nd_na->nd_na_code = 0; 937 nd_na->nd_na_target = *taddr6; 938 if (IN6_IS_SCOPE_LINKLOCAL(&nd_na->nd_na_target)) 939 nd_na->nd_na_target.s6_addr16[1] = 0; 940 941 /* 942 * "tlladdr" indicates NS's condition for adding tlladdr or not. 943 * see nd6_ns_input() for details. 944 * Basically, if NS packet is sent to unicast/anycast addr, 945 * target lladdr option SHOULD NOT be included. 946 */ 947 if (tlladdr) { 948 /* 949 * sdl0 != NULL indicates proxy NA. If we do proxy, use 950 * lladdr in sdl0. If we are not proxying (sending NA for 951 * my address) use lladdr configured for the interface. 952 */ 953 if (sdl0 == NULL) 954 mac = nd6_ifptomac(ifp); 955 else if (sdl0->sa_family == AF_LINK) { 956 struct sockaddr_dl *sdl; 957 sdl = (struct sockaddr_dl *)sdl0; 958 if (sdl->sdl_alen == ifp->if_addrlen) 959 mac = LLADDR(sdl); 960 } 961 } 962 if (tlladdr && mac) { 963 int optlen = sizeof(struct nd_opt_hdr) + ifp->if_addrlen; 964 struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)(nd_na + 1); 965 966 /* roundup to 8 bytes alignment! */ 967 optlen = (optlen + 7) & ~7; 968 969 m->m_pkthdr.len += optlen; 970 m->m_len += optlen; 971 icmp6len += optlen; 972 bzero((caddr_t)nd_opt, optlen); 973 nd_opt->nd_opt_type = ND_OPT_TARGET_LINKADDR; 974 nd_opt->nd_opt_len = optlen >> 3; 975 bcopy(mac, (caddr_t)(nd_opt + 1), ifp->if_addrlen); 976 } else 977 flags &= ~ND_NA_FLAG_OVERRIDE; 978 979 ip6->ip6_plen = htons((u_short)icmp6len); 980 nd_na->nd_na_flags_reserved = flags; 981 nd_na->nd_na_cksum = 0; 982 nd_na->nd_na_cksum = 983 in6_cksum(m, IPPROTO_ICMPV6, sizeof(struct ip6_hdr), icmp6len); 984 985 #ifdef IPSEC 986 /* Don't lookup socket */ 987 (void)ipsec_setsocket(m, NULL); 988 #endif 989 ip6_output(m, NULL, NULL, 0, &im6o, NULL); 990 991 icmp6_ifstat_inc(ifp, ifs6_out_msg); 992 icmp6_ifstat_inc(ifp, ifs6_out_neighboradvert); 993 icmp6stat.icp6s_outhist[ND_NEIGHBOR_ADVERT]++; 994 995 if (ro.ro_rt) { /* we don't cache this route. */ 996 RTFREE(ro.ro_rt); 997 } 998 return; 999 1000 bad: 1001 if (ro.ro_rt) { 1002 RTFREE(ro.ro_rt); 1003 } 1004 m_freem(m); 1005 return; 1006 } 1007 1008 caddr_t 1009 nd6_ifptomac(ifp) 1010 struct ifnet *ifp; 1011 { 1012 switch (ifp->if_type) { 1013 case IFT_ARCNET: 1014 case IFT_ETHER: 1015 case IFT_FDDI: 1016 case IFT_IEEE1394: 1017 case IFT_PROPVIRTUAL: 1018 case IFT_L2VLAN: 1019 case IFT_IEEE80211: 1020 return LLADDR(ifp->if_sadl); 1021 break; 1022 default: 1023 return NULL; 1024 } 1025 } 1026 1027 TAILQ_HEAD(dadq_head, dadq); 1028 struct dadq { 1029 TAILQ_ENTRY(dadq) dad_list; 1030 struct ifaddr *dad_ifa; 1031 int dad_count; /* max NS to send */ 1032 int dad_ns_tcount; /* # of trials to send NS */ 1033 int dad_ns_ocount; /* NS sent so far */ 1034 int dad_ns_icount; 1035 int dad_na_icount; 1036 struct callout dad_timer_ch; 1037 }; 1038 1039 static struct dadq_head dadq; 1040 static int dad_init = 0; 1041 1042 static struct dadq * 1043 nd6_dad_find(ifa) 1044 struct ifaddr *ifa; 1045 { 1046 struct dadq *dp; 1047 1048 for (dp = dadq.tqh_first; dp; dp = dp->dad_list.tqe_next) { 1049 if (dp->dad_ifa == ifa) 1050 return dp; 1051 } 1052 return NULL; 1053 } 1054 1055 static void 1056 nd6_dad_starttimer(dp, ticks) 1057 struct dadq *dp; 1058 int ticks; 1059 { 1060 1061 callout_reset(&dp->dad_timer_ch, ticks, 1062 (void (*) __P((void *)))nd6_dad_timer, (void *)dp->dad_ifa); 1063 } 1064 1065 static void 1066 nd6_dad_stoptimer(dp) 1067 struct dadq *dp; 1068 { 1069 1070 callout_stop(&dp->dad_timer_ch); 1071 } 1072 1073 /* 1074 * Start Duplicated Address Detection (DAD) for specified interface address. 1075 */ 1076 void 1077 nd6_dad_start(ifa, tick) 1078 struct ifaddr *ifa; 1079 int *tick; /* minimum delay ticks for IFF_UP event */ 1080 { 1081 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1082 struct dadq *dp; 1083 1084 if (!dad_init) { 1085 TAILQ_INIT(&dadq); 1086 dad_init++; 1087 } 1088 1089 /* 1090 * If we don't need DAD, don't do it. 1091 * There are several cases: 1092 * - DAD is disabled (ip6_dad_count == 0) 1093 * - the interface address is anycast 1094 */ 1095 if (!(ia->ia6_flags & IN6_IFF_TENTATIVE)) { 1096 log(LOG_DEBUG, 1097 "nd6_dad_start: called with non-tentative address " 1098 "%s(%s)\n", 1099 ip6_sprintf(&ia->ia_addr.sin6_addr), 1100 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1101 return; 1102 } 1103 if (ia->ia6_flags & IN6_IFF_ANYCAST) { 1104 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1105 return; 1106 } 1107 if (!ip6_dad_count) { 1108 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1109 return; 1110 } 1111 if (!ifa->ifa_ifp) 1112 panic("nd6_dad_start: ifa->ifa_ifp == NULL"); 1113 if (!(ifa->ifa_ifp->if_flags & IFF_UP)) 1114 return; 1115 if (nd6_dad_find(ifa) != NULL) { 1116 /* DAD already in progress */ 1117 return; 1118 } 1119 1120 dp = malloc(sizeof(*dp), M_IP6NDP, M_NOWAIT); 1121 if (dp == NULL) { 1122 log(LOG_ERR, "nd6_dad_start: memory allocation failed for " 1123 "%s(%s)\n", 1124 ip6_sprintf(&ia->ia_addr.sin6_addr), 1125 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1126 return; 1127 } 1128 bzero(dp, sizeof(*dp)); 1129 callout_init(&dp->dad_timer_ch); 1130 TAILQ_INSERT_TAIL(&dadq, (struct dadq *)dp, dad_list); 1131 1132 nd6log((LOG_DEBUG, "%s: starting DAD for %s\n", if_name(ifa->ifa_ifp), 1133 ip6_sprintf(&ia->ia_addr.sin6_addr))); 1134 1135 /* 1136 * Send NS packet for DAD, ip6_dad_count times. 1137 * Note that we must delay the first transmission, if this is the 1138 * first packet to be sent from the interface after interface 1139 * (re)initialization. 1140 */ 1141 dp->dad_ifa = ifa; 1142 IFAREF(ifa); /* just for safety */ 1143 dp->dad_count = ip6_dad_count; 1144 dp->dad_ns_icount = dp->dad_na_icount = 0; 1145 dp->dad_ns_ocount = dp->dad_ns_tcount = 0; 1146 if (tick == NULL) { 1147 nd6_dad_ns_output(dp, ifa); 1148 nd6_dad_starttimer(dp, 1149 nd_ifinfo[ifa->ifa_ifp->if_index].retrans * hz / 1000); 1150 } else { 1151 int ntick; 1152 1153 if (*tick == 0) 1154 ntick = random() % (MAX_RTR_SOLICITATION_DELAY * hz); 1155 else 1156 ntick = *tick + random() % (hz / 2); 1157 *tick = ntick; 1158 nd6_dad_starttimer(dp, ntick); 1159 } 1160 } 1161 1162 /* 1163 * terminate DAD unconditionally. used for address removals. 1164 */ 1165 void 1166 nd6_dad_stop(ifa) 1167 struct ifaddr *ifa; 1168 { 1169 struct dadq *dp; 1170 1171 if (!dad_init) 1172 return; 1173 dp = nd6_dad_find(ifa); 1174 if (!dp) { 1175 /* DAD wasn't started yet */ 1176 return; 1177 } 1178 1179 nd6_dad_stoptimer(dp); 1180 1181 TAILQ_REMOVE(&dadq, (struct dadq *)dp, dad_list); 1182 free(dp, M_IP6NDP); 1183 dp = NULL; 1184 IFAFREE(ifa); 1185 } 1186 1187 static void 1188 nd6_dad_timer(ifa) 1189 struct ifaddr *ifa; 1190 { 1191 int s; 1192 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1193 struct dadq *dp; 1194 1195 s = splsoftnet(); /* XXX */ 1196 1197 /* Sanity check */ 1198 if (ia == NULL) { 1199 log(LOG_ERR, "nd6_dad_timer: called with null parameter\n"); 1200 goto done; 1201 } 1202 dp = nd6_dad_find(ifa); 1203 if (dp == NULL) { 1204 log(LOG_ERR, "nd6_dad_timer: DAD structure not found\n"); 1205 goto done; 1206 } 1207 if (ia->ia6_flags & IN6_IFF_DUPLICATED) { 1208 log(LOG_ERR, "nd6_dad_timer: called with duplicated address " 1209 "%s(%s)\n", 1210 ip6_sprintf(&ia->ia_addr.sin6_addr), 1211 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1212 goto done; 1213 } 1214 if ((ia->ia6_flags & IN6_IFF_TENTATIVE) == 0) { 1215 log(LOG_ERR, "nd6_dad_timer: called with non-tentative address " 1216 "%s(%s)\n", 1217 ip6_sprintf(&ia->ia_addr.sin6_addr), 1218 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1219 goto done; 1220 } 1221 1222 /* timeouted with IFF_{RUNNING,UP} check */ 1223 if (dp->dad_ns_tcount > dad_maxtry) { 1224 nd6log((LOG_INFO, "%s: could not run DAD, driver problem?\n", 1225 if_name(ifa->ifa_ifp))); 1226 1227 TAILQ_REMOVE(&dadq, (struct dadq *)dp, dad_list); 1228 free(dp, M_IP6NDP); 1229 dp = NULL; 1230 IFAFREE(ifa); 1231 goto done; 1232 } 1233 1234 /* Need more checks? */ 1235 if (dp->dad_ns_ocount < dp->dad_count) { 1236 /* 1237 * We have more NS to go. Send NS packet for DAD. 1238 */ 1239 nd6_dad_ns_output(dp, ifa); 1240 nd6_dad_starttimer(dp, 1241 nd_ifinfo[ifa->ifa_ifp->if_index].retrans * hz / 1000); 1242 } else { 1243 /* 1244 * We have transmitted sufficient number of DAD packets. 1245 * See what we've got. 1246 */ 1247 int duplicate; 1248 1249 duplicate = 0; 1250 1251 if (dp->dad_na_icount) { 1252 /* 1253 * the check is in nd6_dad_na_input(), 1254 * but just in case 1255 */ 1256 duplicate++; 1257 } 1258 1259 if (dp->dad_ns_icount) { 1260 #if 0 /* heuristics */ 1261 /* 1262 * if 1263 * - we have sent many(?) DAD NS, and 1264 * - the number of NS we sent equals to the 1265 * number of NS we've got, and 1266 * - we've got no NA 1267 * we may have a faulty network card/driver which 1268 * loops back multicasts to myself. 1269 */ 1270 if (3 < dp->dad_count 1271 && dp->dad_ns_icount == dp->dad_count 1272 && dp->dad_na_icount == 0) { 1273 log(LOG_INFO, "DAD questionable for %s(%s): " 1274 "network card loops back multicast?\n", 1275 ip6_sprintf(&ia->ia_addr.sin6_addr), 1276 if_name(ifa->ifa_ifp)); 1277 /* XXX consider it a duplicate or not? */ 1278 /* duplicate++; */ 1279 } else { 1280 /* We've seen NS, means DAD has failed. */ 1281 duplicate++; 1282 } 1283 #else 1284 /* We've seen NS, means DAD has failed. */ 1285 duplicate++; 1286 #endif 1287 } 1288 1289 if (duplicate) { 1290 /* (*dp) will be freed in nd6_dad_duplicated() */ 1291 dp = NULL; 1292 nd6_dad_duplicated(ifa); 1293 } else { 1294 /* 1295 * We are done with DAD. No NA came, no NS came. 1296 * duplicated address found. 1297 */ 1298 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1299 1300 nd6log((LOG_DEBUG, 1301 "%s: DAD complete for %s - no duplicates found\n", 1302 if_name(ifa->ifa_ifp), 1303 ip6_sprintf(&ia->ia_addr.sin6_addr))); 1304 1305 TAILQ_REMOVE(&dadq, (struct dadq *)dp, dad_list); 1306 free(dp, M_IP6NDP); 1307 dp = NULL; 1308 IFAFREE(ifa); 1309 } 1310 } 1311 1312 done: 1313 splx(s); 1314 } 1315 1316 void 1317 nd6_dad_duplicated(ifa) 1318 struct ifaddr *ifa; 1319 { 1320 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1321 struct dadq *dp; 1322 1323 dp = nd6_dad_find(ifa); 1324 if (dp == NULL) { 1325 log(LOG_ERR, "nd6_dad_duplicated: DAD structure not found\n"); 1326 return; 1327 } 1328 1329 log(LOG_ERR, "%s: DAD detected duplicate IPv6 address %s: " 1330 "NS in/out=%d/%d, NA in=%d\n", 1331 if_name(ifa->ifa_ifp), ip6_sprintf(&ia->ia_addr.sin6_addr), 1332 dp->dad_ns_icount, dp->dad_ns_ocount, dp->dad_na_icount); 1333 1334 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1335 ia->ia6_flags |= IN6_IFF_DUPLICATED; 1336 1337 /* We are done with DAD, with duplicated address found. (failure) */ 1338 nd6_dad_stoptimer(dp); 1339 1340 log(LOG_ERR, "%s: DAD complete for %s - duplicate found\n", 1341 if_name(ifa->ifa_ifp), ip6_sprintf(&ia->ia_addr.sin6_addr)); 1342 log(LOG_ERR, "%s: manual intervention required\n", 1343 if_name(ifa->ifa_ifp)); 1344 1345 TAILQ_REMOVE(&dadq, (struct dadq *)dp, dad_list); 1346 free(dp, M_IP6NDP); 1347 dp = NULL; 1348 IFAFREE(ifa); 1349 } 1350 1351 static void 1352 nd6_dad_ns_output(dp, ifa) 1353 struct dadq *dp; 1354 struct ifaddr *ifa; 1355 { 1356 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1357 struct ifnet *ifp = ifa->ifa_ifp; 1358 1359 dp->dad_ns_tcount++; 1360 if ((ifp->if_flags & IFF_UP) == 0) { 1361 #if 0 1362 printf("%s: interface down?\n", if_name(ifp)); 1363 #endif 1364 return; 1365 } 1366 if ((ifp->if_flags & IFF_RUNNING) == 0) { 1367 #if 0 1368 printf("%s: interface not running?\n", if_name(ifp)); 1369 #endif 1370 return; 1371 } 1372 1373 dp->dad_ns_ocount++; 1374 nd6_ns_output(ifp, NULL, &ia->ia_addr.sin6_addr, NULL, 1); 1375 } 1376 1377 static void 1378 nd6_dad_ns_input(ifa) 1379 struct ifaddr *ifa; 1380 { 1381 struct in6_ifaddr *ia; 1382 struct ifnet *ifp; 1383 const struct in6_addr *taddr6; 1384 struct dadq *dp; 1385 int duplicate; 1386 1387 if (!ifa) 1388 panic("ifa == NULL in nd6_dad_ns_input"); 1389 1390 ia = (struct in6_ifaddr *)ifa; 1391 ifp = ifa->ifa_ifp; 1392 taddr6 = &ia->ia_addr.sin6_addr; 1393 duplicate = 0; 1394 dp = nd6_dad_find(ifa); 1395 1396 /* Quickhack - completely ignore DAD NS packets */ 1397 if (dad_ignore_ns) { 1398 nd6log((LOG_INFO, 1399 "nd6_dad_ns_input: ignoring DAD NS packet for " 1400 "address %s(%s)\n", ip6_sprintf(taddr6), 1401 if_name(ifa->ifa_ifp))); 1402 return; 1403 } 1404 1405 /* 1406 * if I'm yet to start DAD, someone else started using this address 1407 * first. I have a duplicate and you win. 1408 */ 1409 if (!dp || dp->dad_ns_ocount == 0) 1410 duplicate++; 1411 1412 /* XXX more checks for loopback situation - see nd6_dad_timer too */ 1413 1414 if (duplicate) { 1415 dp = NULL; /* will be freed in nd6_dad_duplicated() */ 1416 nd6_dad_duplicated(ifa); 1417 } else { 1418 /* 1419 * not sure if I got a duplicate. 1420 * increment ns count and see what happens. 1421 */ 1422 if (dp) 1423 dp->dad_ns_icount++; 1424 } 1425 } 1426 1427 static void 1428 nd6_dad_na_input(ifa) 1429 struct ifaddr *ifa; 1430 { 1431 struct dadq *dp; 1432 1433 if (!ifa) 1434 panic("ifa == NULL in nd6_dad_na_input"); 1435 1436 dp = nd6_dad_find(ifa); 1437 if (dp) 1438 dp->dad_na_icount++; 1439 1440 /* remove the address. */ 1441 nd6_dad_duplicated(ifa); 1442 } 1443
Indexes created Mon Oct 27 04:09:48 GMT 2025