nd6_nbr.c revision 1.51
1 /* $NetBSD: nd6_nbr.c,v 1.51 2003/09/05 23:20:48 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 1.51 2003/09/05 23:20:48 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_int16_t)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 ip6_output(m, NULL, &ro, dad ? IPV6_UNSPECSRC : 0, 507 &im6o, (struct socket *)NULL, NULL); 508 icmp6_ifstat_inc(ifp, ifs6_out_msg); 509 icmp6_ifstat_inc(ifp, ifs6_out_neighborsolicit); 510 icmp6stat.icp6s_outhist[ND_NEIGHBOR_SOLICIT]++; 511 512 if (ro.ro_rt) { /* we don't cache this route. */ 513 RTFREE(ro.ro_rt); 514 } 515 return; 516 517 bad: 518 if (ro.ro_rt) { 519 RTFREE(ro.ro_rt); 520 } 521 m_freem(m); 522 return; 523 } 524 525 /* 526 * Neighbor advertisement input handling. 527 * 528 * Based on RFC 2461 529 * Based on RFC 2462 (duplicated address detection) 530 * 531 * the following items are not implemented yet: 532 * - proxy advertisement delay rule (RFC2461 7.2.8, last paragraph, SHOULD) 533 * - anycast advertisement delay rule (RFC2461 7.2.7, SHOULD) 534 */ 535 void 536 nd6_na_input(m, off, icmp6len) 537 struct mbuf *m; 538 int off, icmp6len; 539 { 540 struct ifnet *ifp = m->m_pkthdr.rcvif; 541 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 542 struct nd_neighbor_advert *nd_na; 543 #if 0 544 struct in6_addr saddr6 = ip6->ip6_src; 545 #endif 546 struct in6_addr daddr6 = ip6->ip6_dst; 547 struct in6_addr taddr6; 548 int flags; 549 int is_router; 550 int is_solicited; 551 int is_override; 552 char *lladdr = NULL; 553 int lladdrlen = 0; 554 struct ifaddr *ifa; 555 struct llinfo_nd6 *ln; 556 struct rtentry *rt; 557 struct sockaddr_dl *sdl; 558 union nd_opts ndopts; 559 560 if (ip6->ip6_hlim != 255) { 561 nd6log((LOG_ERR, 562 "nd6_na_input: invalid hlim (%d) from %s to %s on %s\n", 563 ip6->ip6_hlim, ip6_sprintf(&ip6->ip6_src), 564 ip6_sprintf(&ip6->ip6_dst), if_name(ifp))); 565 goto bad; 566 } 567 568 IP6_EXTHDR_GET(nd_na, struct nd_neighbor_advert *, m, off, icmp6len); 569 if (nd_na == NULL) { 570 icmp6stat.icp6s_tooshort++; 571 return; 572 } 573 taddr6 = nd_na->nd_na_target; 574 flags = nd_na->nd_na_flags_reserved; 575 is_router = ((flags & ND_NA_FLAG_ROUTER) != 0); 576 is_solicited = ((flags & ND_NA_FLAG_SOLICITED) != 0); 577 is_override = ((flags & ND_NA_FLAG_OVERRIDE) != 0); 578 579 if (IN6_IS_SCOPE_LINKLOCAL(&taddr6)) 580 taddr6.s6_addr16[1] = htons(ifp->if_index); 581 582 if (IN6_IS_ADDR_MULTICAST(&taddr6)) { 583 nd6log((LOG_ERR, 584 "nd6_na_input: invalid target address %s\n", 585 ip6_sprintf(&taddr6))); 586 goto bad; 587 } 588 if (is_solicited && IN6_IS_ADDR_MULTICAST(&daddr6)) { 589 nd6log((LOG_ERR, 590 "nd6_na_input: a solicited adv is multicasted\n")); 591 goto bad; 592 } 593 594 icmp6len -= sizeof(*nd_na); 595 nd6_option_init(nd_na + 1, icmp6len, &ndopts); 596 if (nd6_options(&ndopts) < 0) { 597 nd6log((LOG_INFO, 598 "nd6_na_input: invalid ND option, ignored\n")); 599 /* nd6_options have incremented stats */ 600 goto freeit; 601 } 602 603 if (ndopts.nd_opts_tgt_lladdr) { 604 lladdr = (char *)(ndopts.nd_opts_tgt_lladdr + 1); 605 lladdrlen = ndopts.nd_opts_tgt_lladdr->nd_opt_len << 3; 606 } 607 608 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &taddr6); 609 610 /* 611 * Target address matches one of my interface address. 612 * 613 * If my address is tentative, this means that there's somebody 614 * already using the same address as mine. This indicates DAD failure. 615 * This is defined in RFC 2462. 616 * 617 * Otherwise, process as defined in RFC 2461. 618 */ 619 if (ifa 620 && (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_TENTATIVE)) { 621 nd6_dad_na_input(ifa); 622 goto freeit; 623 } 624 625 /* Just for safety, maybe unnecessary. */ 626 if (ifa) { 627 log(LOG_ERR, 628 "nd6_na_input: duplicate IP6 address %s\n", 629 ip6_sprintf(&taddr6)); 630 goto freeit; 631 } 632 633 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) { 634 nd6log((LOG_INFO, "nd6_na_input: lladdrlen mismatch for %s " 635 "(if %d, NA packet %d)\n", ip6_sprintf(&taddr6), 636 ifp->if_addrlen, lladdrlen - 2)); 637 goto bad; 638 } 639 640 /* 641 * If no neighbor cache entry is found, NA SHOULD silently be 642 * discarded. 643 */ 644 rt = nd6_lookup(&taddr6, 0, ifp); 645 if ((rt == NULL) || 646 ((ln = (struct llinfo_nd6 *)rt->rt_llinfo) == NULL) || 647 ((sdl = SDL(rt->rt_gateway)) == NULL)) 648 goto freeit; 649 650 if (ln->ln_state == ND6_LLINFO_INCOMPLETE) { 651 /* 652 * If the link-layer has address, and no lladdr option came, 653 * discard the packet. 654 */ 655 if (ifp->if_addrlen && !lladdr) 656 goto freeit; 657 658 /* 659 * Record link-layer address, and update the state. 660 */ 661 sdl->sdl_alen = ifp->if_addrlen; 662 bcopy(lladdr, LLADDR(sdl), ifp->if_addrlen); 663 if (is_solicited) { 664 ln->ln_state = ND6_LLINFO_REACHABLE; 665 ln->ln_byhint = 0; 666 if (!ND6_LLINFO_PERMANENT(ln)) { 667 nd6_llinfo_settimer(ln, 668 (long)ND_IFINFO(rt->rt_ifp)->reachable * hz); 669 } 670 } else { 671 ln->ln_state = ND6_LLINFO_STALE; 672 nd6_llinfo_settimer(ln, (long)nd6_gctimer * hz); 673 } 674 if ((ln->ln_router = is_router) != 0) { 675 /* 676 * This means a router's state has changed from 677 * non-reachable to probably reachable, and might 678 * affect the status of associated prefixes.. 679 */ 680 pfxlist_onlink_check(); 681 } 682 } else { 683 int llchange; 684 685 /* 686 * Check if the link-layer address has changed or not. 687 */ 688 if (!lladdr) 689 llchange = 0; 690 else { 691 if (sdl->sdl_alen) { 692 if (bcmp(lladdr, LLADDR(sdl), ifp->if_addrlen)) 693 llchange = 1; 694 else 695 llchange = 0; 696 } else 697 llchange = 1; 698 } 699 700 /* 701 * This is VERY complex. Look at it with care. 702 * 703 * override solicit lladdr llchange action 704 * (L: record lladdr) 705 * 706 * 0 0 n -- (2c) 707 * 0 0 y n (2b) L 708 * 0 0 y y (1) REACHABLE->STALE 709 * 0 1 n -- (2c) *->REACHABLE 710 * 0 1 y n (2b) L *->REACHABLE 711 * 0 1 y y (1) REACHABLE->STALE 712 * 1 0 n -- (2a) 713 * 1 0 y n (2a) L 714 * 1 0 y y (2a) L *->STALE 715 * 1 1 n -- (2a) *->REACHABLE 716 * 1 1 y n (2a) L *->REACHABLE 717 * 1 1 y y (2a) L *->REACHABLE 718 */ 719 if (!is_override && (lladdr && llchange)) { /* (1) */ 720 /* 721 * If state is REACHABLE, make it STALE. 722 * no other updates should be done. 723 */ 724 if (ln->ln_state == ND6_LLINFO_REACHABLE) { 725 ln->ln_state = ND6_LLINFO_STALE; 726 nd6_llinfo_settimer(ln, (long)nd6_gctimer * hz); 727 } 728 goto freeit; 729 } else if (is_override /* (2a) */ 730 || (!is_override && (lladdr && !llchange)) /* (2b) */ 731 || !lladdr) { /* (2c) */ 732 /* 733 * Update link-local address, if any. 734 */ 735 if (lladdr) { 736 sdl->sdl_alen = ifp->if_addrlen; 737 bcopy(lladdr, LLADDR(sdl), ifp->if_addrlen); 738 } 739 740 /* 741 * If solicited, make the state REACHABLE. 742 * If not solicited and the link-layer address was 743 * changed, make it STALE. 744 */ 745 if (is_solicited) { 746 ln->ln_state = ND6_LLINFO_REACHABLE; 747 ln->ln_byhint = 0; 748 if (!ND6_LLINFO_PERMANENT(ln)) { 749 nd6_llinfo_settimer(ln, 750 (long)ND_IFINFO(ifp)->reachable * hz); 751 } 752 } else { 753 if (lladdr && llchange) { 754 ln->ln_state = ND6_LLINFO_STALE; 755 nd6_llinfo_settimer(ln, 756 (long)nd6_gctimer * hz); 757 } 758 } 759 } 760 761 if (ln->ln_router && !is_router) { 762 /* 763 * The peer dropped the router flag. 764 * Remove the sender from the Default Router List and 765 * update the Destination Cache entries. 766 */ 767 struct nd_defrouter *dr; 768 struct in6_addr *in6; 769 int s; 770 771 in6 = &((struct sockaddr_in6 *)rt_key(rt))->sin6_addr; 772 773 /* 774 * Lock to protect the default router list. 775 * XXX: this might be unnecessary, since this function 776 * is only called under the network software interrupt 777 * context. However, we keep it just for safety. 778 */ 779 s = splsoftnet(); 780 dr = defrouter_lookup(in6, rt->rt_ifp); 781 if (dr) 782 defrtrlist_del(dr); 783 else if (!ip6_forwarding) { 784 /* 785 * Even if the neighbor is not in the default 786 * router list, the neighbor may be used 787 * as a next hop for some destinations 788 * (e.g. redirect case). So we must 789 * call rt6_flush explicitly. 790 */ 791 rt6_flush(&ip6->ip6_src, rt->rt_ifp); 792 } 793 splx(s); 794 } 795 ln->ln_router = is_router; 796 } 797 rt->rt_flags &= ~RTF_REJECT; 798 ln->ln_asked = 0; 799 if (ln->ln_hold) { 800 /* 801 * we assume ifp is not a loopback here, so just set the 2nd 802 * argument as the 1st one. 803 */ 804 nd6_output(ifp, ifp, ln->ln_hold, 805 (struct sockaddr_in6 *)rt_key(rt), rt); 806 ln->ln_hold = NULL; 807 } 808 809 freeit: 810 m_freem(m); 811 return; 812 813 bad: 814 icmp6stat.icp6s_badna++; 815 m_freem(m); 816 } 817 818 /* 819 * Neighbor advertisement output handling. 820 * 821 * Based on RFC 2461 822 * 823 * the following items are not implemented yet: 824 * - proxy advertisement delay rule (RFC2461 7.2.8, last paragraph, SHOULD) 825 * - anycast advertisement delay rule (RFC2461 7.2.7, SHOULD) 826 */ 827 void 828 nd6_na_output(ifp, daddr6, taddr6, flags, tlladdr, sdl0) 829 struct ifnet *ifp; 830 const struct in6_addr *daddr6, *taddr6; 831 u_long flags; 832 int tlladdr; /* 1 if include target link-layer address */ 833 struct sockaddr *sdl0; /* sockaddr_dl (= proxy NA) or NULL */ 834 { 835 struct mbuf *m; 836 struct ip6_hdr *ip6; 837 struct nd_neighbor_advert *nd_na; 838 struct ip6_moptions im6o; 839 struct sockaddr_in6 src_sa, dst_sa; 840 struct in6_addr *src0; 841 int icmp6len, maxlen, error; 842 caddr_t mac; 843 struct route_in6 ro; 844 845 mac = NULL; 846 bzero(&ro, sizeof(ro)); 847 848 /* estimate the size of message */ 849 maxlen = sizeof(*ip6) + sizeof(*nd_na); 850 maxlen += (sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7; 851 #ifdef DIAGNOSTIC 852 if (max_linkhdr + maxlen >= MCLBYTES) { 853 printf("nd6_na_output: max_linkhdr + maxlen >= MCLBYTES " 854 "(%d + %d > %d)\n", max_linkhdr, maxlen, MCLBYTES); 855 panic("nd6_na_output: insufficient MCLBYTES"); 856 /* NOTREACHED */ 857 } 858 #endif 859 860 MGETHDR(m, M_DONTWAIT, MT_DATA); 861 if (m && max_linkhdr + maxlen >= MHLEN) { 862 MCLGET(m, M_DONTWAIT); 863 if ((m->m_flags & M_EXT) == 0) { 864 m_free(m); 865 m = NULL; 866 } 867 } 868 if (m == NULL) 869 return; 870 m->m_pkthdr.rcvif = NULL; 871 872 if (IN6_IS_ADDR_MULTICAST(daddr6)) { 873 m->m_flags |= M_MCAST; 874 im6o.im6o_multicast_ifp = ifp; 875 im6o.im6o_multicast_hlim = 255; 876 im6o.im6o_multicast_loop = 0; 877 } 878 879 icmp6len = sizeof(*nd_na); 880 m->m_pkthdr.len = m->m_len = sizeof(struct ip6_hdr) + icmp6len; 881 m->m_data += max_linkhdr; /* or MH_ALIGN() equivalent? */ 882 883 /* fill neighbor advertisement packet */ 884 ip6 = mtod(m, struct ip6_hdr *); 885 ip6->ip6_flow = 0; 886 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 887 ip6->ip6_vfc |= IPV6_VERSION; 888 ip6->ip6_nxt = IPPROTO_ICMPV6; 889 ip6->ip6_hlim = 255; 890 bzero(&src_sa, sizeof(src_sa)); 891 bzero(&dst_sa, sizeof(dst_sa)); 892 src_sa.sin6_len = dst_sa.sin6_len = sizeof(struct sockaddr_in6); 893 src_sa.sin6_family = dst_sa.sin6_family = AF_INET6; 894 dst_sa.sin6_addr = *daddr6; 895 if (IN6_IS_ADDR_UNSPECIFIED(daddr6)) { 896 /* reply to DAD */ 897 dst_sa.sin6_addr.s6_addr16[0] = IPV6_ADDR_INT16_MLL; 898 dst_sa.sin6_addr.s6_addr16[1] = htons(ifp->if_index); 899 dst_sa.sin6_addr.s6_addr32[1] = 0; 900 dst_sa.sin6_addr.s6_addr32[2] = 0; 901 dst_sa.sin6_addr.s6_addr32[3] = IPV6_ADDR_INT32_ONE; 902 903 flags &= ~ND_NA_FLAG_SOLICITED; 904 } 905 ip6->ip6_dst = dst_sa.sin6_addr; 906 907 /* 908 * Select a source whose scope is the same as that of the dest. 909 */ 910 bcopy(&dst_sa, &ro.ro_dst, sizeof(dst_sa)); 911 src0 = in6_selectsrc(&dst_sa, NULL, NULL, &ro, NULL, &error); 912 if (src0 == NULL) { 913 nd6log((LOG_DEBUG, "nd6_na_output: source can't be " 914 "determined: dst=%s, error=%d\n", 915 ip6_sprintf(&dst_sa.sin6_addr), error)); 916 goto bad; 917 } 918 src_sa.sin6_addr = *src0; 919 ip6->ip6_src = src_sa.sin6_addr; 920 nd_na = (struct nd_neighbor_advert *)(ip6 + 1); 921 nd_na->nd_na_type = ND_NEIGHBOR_ADVERT; 922 nd_na->nd_na_code = 0; 923 nd_na->nd_na_target = *taddr6; 924 if (IN6_IS_SCOPE_LINKLOCAL(&nd_na->nd_na_target)) 925 nd_na->nd_na_target.s6_addr16[1] = 0; 926 927 /* 928 * "tlladdr" indicates NS's condition for adding tlladdr or not. 929 * see nd6_ns_input() for details. 930 * Basically, if NS packet is sent to unicast/anycast addr, 931 * target lladdr option SHOULD NOT be included. 932 */ 933 if (tlladdr) { 934 /* 935 * sdl0 != NULL indicates proxy NA. If we do proxy, use 936 * lladdr in sdl0. If we are not proxying (sending NA for 937 * my address) use lladdr configured for the interface. 938 */ 939 if (sdl0 == NULL) 940 mac = nd6_ifptomac(ifp); 941 else if (sdl0->sa_family == AF_LINK) { 942 struct sockaddr_dl *sdl; 943 sdl = (struct sockaddr_dl *)sdl0; 944 if (sdl->sdl_alen == ifp->if_addrlen) 945 mac = LLADDR(sdl); 946 } 947 } 948 if (tlladdr && mac) { 949 int optlen = sizeof(struct nd_opt_hdr) + ifp->if_addrlen; 950 struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)(nd_na + 1); 951 952 /* roundup to 8 bytes alignment! */ 953 optlen = (optlen + 7) & ~7; 954 955 m->m_pkthdr.len += optlen; 956 m->m_len += optlen; 957 icmp6len += optlen; 958 bzero((caddr_t)nd_opt, optlen); 959 nd_opt->nd_opt_type = ND_OPT_TARGET_LINKADDR; 960 nd_opt->nd_opt_len = optlen >> 3; 961 bcopy(mac, (caddr_t)(nd_opt + 1), ifp->if_addrlen); 962 } else 963 flags &= ~ND_NA_FLAG_OVERRIDE; 964 965 ip6->ip6_plen = htons((u_int16_t)icmp6len); 966 nd_na->nd_na_flags_reserved = flags; 967 nd_na->nd_na_cksum = 0; 968 nd_na->nd_na_cksum = 969 in6_cksum(m, IPPROTO_ICMPV6, sizeof(struct ip6_hdr), icmp6len); 970 971 ip6_output(m, NULL, NULL, 0, &im6o, (struct socket *)NULL, NULL); 972 973 icmp6_ifstat_inc(ifp, ifs6_out_msg); 974 icmp6_ifstat_inc(ifp, ifs6_out_neighboradvert); 975 icmp6stat.icp6s_outhist[ND_NEIGHBOR_ADVERT]++; 976 977 if (ro.ro_rt) { /* we don't cache this route. */ 978 RTFREE(ro.ro_rt); 979 } 980 return; 981 982 bad: 983 if (ro.ro_rt) { 984 RTFREE(ro.ro_rt); 985 } 986 m_freem(m); 987 return; 988 } 989 990 caddr_t 991 nd6_ifptomac(ifp) 992 struct ifnet *ifp; 993 { 994 switch (ifp->if_type) { 995 case IFT_ARCNET: 996 case IFT_ETHER: 997 case IFT_FDDI: 998 case IFT_IEEE1394: 999 case IFT_PROPVIRTUAL: 1000 case IFT_L2VLAN: 1001 case IFT_IEEE80211: 1002 return LLADDR(ifp->if_sadl); 1003 default: 1004 return NULL; 1005 } 1006 } 1007 1008 TAILQ_HEAD(dadq_head, dadq); 1009 struct dadq { 1010 TAILQ_ENTRY(dadq) dad_list; 1011 struct ifaddr *dad_ifa; 1012 int dad_count; /* max NS to send */ 1013 int dad_ns_tcount; /* # of trials to send NS */ 1014 int dad_ns_ocount; /* NS sent so far */ 1015 int dad_ns_icount; 1016 int dad_na_icount; 1017 struct callout dad_timer_ch; 1018 }; 1019 1020 static struct dadq_head dadq; 1021 static int dad_init = 0; 1022 1023 static struct dadq * 1024 nd6_dad_find(ifa) 1025 struct ifaddr *ifa; 1026 { 1027 struct dadq *dp; 1028 1029 for (dp = dadq.tqh_first; dp; dp = dp->dad_list.tqe_next) { 1030 if (dp->dad_ifa == ifa) 1031 return dp; 1032 } 1033 return NULL; 1034 } 1035 1036 static void 1037 nd6_dad_starttimer(dp, ticks) 1038 struct dadq *dp; 1039 int ticks; 1040 { 1041 1042 callout_reset(&dp->dad_timer_ch, ticks, 1043 (void (*) __P((void *)))nd6_dad_timer, (void *)dp->dad_ifa); 1044 } 1045 1046 static void 1047 nd6_dad_stoptimer(dp) 1048 struct dadq *dp; 1049 { 1050 1051 callout_stop(&dp->dad_timer_ch); 1052 } 1053 1054 /* 1055 * Start Duplicated Address Detection (DAD) for specified interface address. 1056 */ 1057 void 1058 nd6_dad_start(ifa, tick) 1059 struct ifaddr *ifa; 1060 int *tick; /* minimum delay ticks for IFF_UP event */ 1061 { 1062 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1063 struct dadq *dp; 1064 1065 if (!dad_init) { 1066 TAILQ_INIT(&dadq); 1067 dad_init++; 1068 } 1069 1070 /* 1071 * If we don't need DAD, don't do it. 1072 * There are several cases: 1073 * - DAD is disabled (ip6_dad_count == 0) 1074 * - the interface address is anycast 1075 */ 1076 if (!(ia->ia6_flags & IN6_IFF_TENTATIVE)) { 1077 log(LOG_DEBUG, 1078 "nd6_dad_start: called with non-tentative address " 1079 "%s(%s)\n", 1080 ip6_sprintf(&ia->ia_addr.sin6_addr), 1081 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1082 return; 1083 } 1084 if (ia->ia6_flags & IN6_IFF_ANYCAST) { 1085 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1086 return; 1087 } 1088 if (!ip6_dad_count) { 1089 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1090 return; 1091 } 1092 if (!ifa->ifa_ifp) 1093 panic("nd6_dad_start: ifa->ifa_ifp == NULL"); 1094 if (!(ifa->ifa_ifp->if_flags & IFF_UP)) 1095 return; 1096 if (nd6_dad_find(ifa) != NULL) { 1097 /* DAD already in progress */ 1098 return; 1099 } 1100 1101 dp = malloc(sizeof(*dp), M_IP6NDP, M_NOWAIT); 1102 if (dp == NULL) { 1103 log(LOG_ERR, "nd6_dad_start: memory allocation failed for " 1104 "%s(%s)\n", 1105 ip6_sprintf(&ia->ia_addr.sin6_addr), 1106 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1107 return; 1108 } 1109 bzero(dp, sizeof(*dp)); 1110 callout_init(&dp->dad_timer_ch); 1111 TAILQ_INSERT_TAIL(&dadq, (struct dadq *)dp, dad_list); 1112 1113 nd6log((LOG_DEBUG, "%s: starting DAD for %s\n", if_name(ifa->ifa_ifp), 1114 ip6_sprintf(&ia->ia_addr.sin6_addr))); 1115 1116 /* 1117 * Send NS packet for DAD, ip6_dad_count times. 1118 * Note that we must delay the first transmission, if this is the 1119 * first packet to be sent from the interface after interface 1120 * (re)initialization. 1121 */ 1122 dp->dad_ifa = ifa; 1123 IFAREF(ifa); /* just for safety */ 1124 dp->dad_count = ip6_dad_count; 1125 dp->dad_ns_icount = dp->dad_na_icount = 0; 1126 dp->dad_ns_ocount = dp->dad_ns_tcount = 0; 1127 if (tick == NULL) { 1128 nd6_dad_ns_output(dp, ifa); 1129 nd6_dad_starttimer(dp, 1130 (long)ND_IFINFO(ifa->ifa_ifp)->retrans * hz / 1000); 1131 } else { 1132 int ntick; 1133 1134 if (*tick == 0) 1135 ntick = arc4random() % (MAX_RTR_SOLICITATION_DELAY * hz); 1136 else 1137 ntick = *tick + arc4random() % (hz / 2); 1138 *tick = ntick; 1139 nd6_dad_starttimer(dp, ntick); 1140 } 1141 } 1142 1143 /* 1144 * terminate DAD unconditionally. used for address removals. 1145 */ 1146 void 1147 nd6_dad_stop(ifa) 1148 struct ifaddr *ifa; 1149 { 1150 struct dadq *dp; 1151 1152 if (!dad_init) 1153 return; 1154 dp = nd6_dad_find(ifa); 1155 if (!dp) { 1156 /* DAD wasn't started yet */ 1157 return; 1158 } 1159 1160 nd6_dad_stoptimer(dp); 1161 1162 TAILQ_REMOVE(&dadq, (struct dadq *)dp, dad_list); 1163 free(dp, M_IP6NDP); 1164 dp = NULL; 1165 IFAFREE(ifa); 1166 } 1167 1168 static void 1169 nd6_dad_timer(ifa) 1170 struct ifaddr *ifa; 1171 { 1172 int s; 1173 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1174 struct dadq *dp; 1175 1176 s = splsoftnet(); /* XXX */ 1177 1178 /* Sanity check */ 1179 if (ia == NULL) { 1180 log(LOG_ERR, "nd6_dad_timer: called with null parameter\n"); 1181 goto done; 1182 } 1183 dp = nd6_dad_find(ifa); 1184 if (dp == NULL) { 1185 log(LOG_ERR, "nd6_dad_timer: DAD structure not found\n"); 1186 goto done; 1187 } 1188 if (ia->ia6_flags & IN6_IFF_DUPLICATED) { 1189 log(LOG_ERR, "nd6_dad_timer: called with duplicated address " 1190 "%s(%s)\n", 1191 ip6_sprintf(&ia->ia_addr.sin6_addr), 1192 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1193 goto done; 1194 } 1195 if ((ia->ia6_flags & IN6_IFF_TENTATIVE) == 0) { 1196 log(LOG_ERR, "nd6_dad_timer: called with non-tentative 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 1203 /* timeouted with IFF_{RUNNING,UP} check */ 1204 if (dp->dad_ns_tcount > dad_maxtry) { 1205 nd6log((LOG_INFO, "%s: could not run DAD, driver problem?\n", 1206 if_name(ifa->ifa_ifp))); 1207 1208 TAILQ_REMOVE(&dadq, (struct dadq *)dp, dad_list); 1209 free(dp, M_IP6NDP); 1210 dp = NULL; 1211 IFAFREE(ifa); 1212 goto done; 1213 } 1214 1215 /* Need more checks? */ 1216 if (dp->dad_ns_ocount < dp->dad_count) { 1217 /* 1218 * We have more NS to go. Send NS packet for DAD. 1219 */ 1220 nd6_dad_ns_output(dp, ifa); 1221 nd6_dad_starttimer(dp, 1222 (long)ND_IFINFO(ifa->ifa_ifp)->retrans * hz / 1000); 1223 } else { 1224 /* 1225 * We have transmitted sufficient number of DAD packets. 1226 * See what we've got. 1227 */ 1228 int duplicate; 1229 1230 duplicate = 0; 1231 1232 if (dp->dad_na_icount) { 1233 /* 1234 * the check is in nd6_dad_na_input(), 1235 * but just in case 1236 */ 1237 duplicate++; 1238 } 1239 1240 if (dp->dad_ns_icount) { 1241 #if 0 /* heuristics */ 1242 /* 1243 * if 1244 * - we have sent many(?) DAD NS, and 1245 * - the number of NS we sent equals to the 1246 * number of NS we've got, and 1247 * - we've got no NA 1248 * we may have a faulty network card/driver which 1249 * loops back multicasts to myself. 1250 */ 1251 if (3 < dp->dad_count 1252 && dp->dad_ns_icount == dp->dad_count 1253 && dp->dad_na_icount == 0) { 1254 log(LOG_INFO, "DAD questionable for %s(%s): " 1255 "network card loops back multicast?\n", 1256 ip6_sprintf(&ia->ia_addr.sin6_addr), 1257 if_name(ifa->ifa_ifp)); 1258 /* XXX consider it a duplicate or not? */ 1259 /* duplicate++; */ 1260 } else { 1261 /* We've seen NS, means DAD has failed. */ 1262 duplicate++; 1263 } 1264 #else 1265 /* We've seen NS, means DAD has failed. */ 1266 duplicate++; 1267 #endif 1268 } 1269 1270 if (duplicate) { 1271 /* (*dp) will be freed in nd6_dad_duplicated() */ 1272 dp = NULL; 1273 nd6_dad_duplicated(ifa); 1274 } else { 1275 /* 1276 * We are done with DAD. No NA came, no NS came. 1277 * duplicated address found. 1278 */ 1279 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1280 1281 nd6log((LOG_DEBUG, 1282 "%s: DAD complete for %s - no duplicates found\n", 1283 if_name(ifa->ifa_ifp), 1284 ip6_sprintf(&ia->ia_addr.sin6_addr))); 1285 1286 TAILQ_REMOVE(&dadq, (struct dadq *)dp, dad_list); 1287 free(dp, M_IP6NDP); 1288 dp = NULL; 1289 IFAFREE(ifa); 1290 } 1291 } 1292 1293 done: 1294 splx(s); 1295 } 1296 1297 void 1298 nd6_dad_duplicated(ifa) 1299 struct ifaddr *ifa; 1300 { 1301 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1302 struct dadq *dp; 1303 1304 dp = nd6_dad_find(ifa); 1305 if (dp == NULL) { 1306 log(LOG_ERR, "nd6_dad_duplicated: DAD structure not found\n"); 1307 return; 1308 } 1309 1310 log(LOG_ERR, "%s: DAD detected duplicate IPv6 address %s: " 1311 "NS in/out=%d/%d, NA in=%d\n", 1312 if_name(ifa->ifa_ifp), ip6_sprintf(&ia->ia_addr.sin6_addr), 1313 dp->dad_ns_icount, dp->dad_ns_ocount, dp->dad_na_icount); 1314 1315 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1316 ia->ia6_flags |= IN6_IFF_DUPLICATED; 1317 1318 /* We are done with DAD, with duplicated address found. (failure) */ 1319 nd6_dad_stoptimer(dp); 1320 1321 log(LOG_ERR, "%s: DAD complete for %s - duplicate found\n", 1322 if_name(ifa->ifa_ifp), ip6_sprintf(&ia->ia_addr.sin6_addr)); 1323 log(LOG_ERR, "%s: manual intervention required\n", 1324 if_name(ifa->ifa_ifp)); 1325 1326 TAILQ_REMOVE(&dadq, (struct dadq *)dp, dad_list); 1327 free(dp, M_IP6NDP); 1328 dp = NULL; 1329 IFAFREE(ifa); 1330 } 1331 1332 static void 1333 nd6_dad_ns_output(dp, ifa) 1334 struct dadq *dp; 1335 struct ifaddr *ifa; 1336 { 1337 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1338 struct ifnet *ifp = ifa->ifa_ifp; 1339 1340 dp->dad_ns_tcount++; 1341 if ((ifp->if_flags & IFF_UP) == 0) { 1342 #if 0 1343 printf("%s: interface down?\n", if_name(ifp)); 1344 #endif 1345 return; 1346 } 1347 if ((ifp->if_flags & IFF_RUNNING) == 0) { 1348 #if 0 1349 printf("%s: interface not running?\n", if_name(ifp)); 1350 #endif 1351 return; 1352 } 1353 1354 dp->dad_ns_ocount++; 1355 nd6_ns_output(ifp, NULL, &ia->ia_addr.sin6_addr, NULL, 1); 1356 } 1357 1358 static void 1359 nd6_dad_ns_input(ifa) 1360 struct ifaddr *ifa; 1361 { 1362 struct in6_ifaddr *ia; 1363 struct ifnet *ifp; 1364 const struct in6_addr *taddr6; 1365 struct dadq *dp; 1366 int duplicate; 1367 1368 if (!ifa) 1369 panic("ifa == NULL in nd6_dad_ns_input"); 1370 1371 ia = (struct in6_ifaddr *)ifa; 1372 ifp = ifa->ifa_ifp; 1373 taddr6 = &ia->ia_addr.sin6_addr; 1374 duplicate = 0; 1375 dp = nd6_dad_find(ifa); 1376 1377 /* Quickhack - completely ignore DAD NS packets */ 1378 if (dad_ignore_ns) { 1379 nd6log((LOG_INFO, 1380 "nd6_dad_ns_input: ignoring DAD NS packet for " 1381 "address %s(%s)\n", ip6_sprintf(taddr6), 1382 if_name(ifa->ifa_ifp))); 1383 return; 1384 } 1385 1386 /* 1387 * if I'm yet to start DAD, someone else started using this address 1388 * first. I have a duplicate and you win. 1389 */ 1390 if (!dp || dp->dad_ns_ocount == 0) 1391 duplicate++; 1392 1393 /* XXX more checks for loopback situation - see nd6_dad_timer too */ 1394 1395 if (duplicate) { 1396 dp = NULL; /* will be freed in nd6_dad_duplicated() */ 1397 nd6_dad_duplicated(ifa); 1398 } else { 1399 /* 1400 * not sure if I got a duplicate. 1401 * increment ns count and see what happens. 1402 */ 1403 if (dp) 1404 dp->dad_ns_icount++; 1405 } 1406 } 1407 1408 static void 1409 nd6_dad_na_input(ifa) 1410 struct ifaddr *ifa; 1411 { 1412 struct dadq *dp; 1413 1414 if (!ifa) 1415 panic("ifa == NULL in nd6_dad_na_input"); 1416 1417 dp = nd6_dad_find(ifa); 1418 if (dp) 1419 dp->dad_na_icount++; 1420 1421 /* remove the address. */ 1422 nd6_dad_duplicated(ifa); 1423 } 1424
Indexes created Sat Sep 27 22:09:54 GMT 2025