1 /* $NetBSD: nd6_nbr.c,v 1.58 2005/12/11 12:25:02 christos 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 1.58 2005/12/11 12:25:02 christos 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 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(&dst_sa, sizeof(dst_sa)); 891 dst_sa.sin6_len = sizeof(struct sockaddr_in6); 892 dst_sa.sin6_family = AF_INET6; 893 dst_sa.sin6_addr = *daddr6; 894 if (IN6_IS_ADDR_UNSPECIFIED(daddr6)) { 895 /* reply to DAD */ 896 dst_sa.sin6_addr.s6_addr16[0] = IPV6_ADDR_INT16_MLL; 897 dst_sa.sin6_addr.s6_addr16[1] = htons(ifp->if_index); 898 dst_sa.sin6_addr.s6_addr32[1] = 0; 899 dst_sa.sin6_addr.s6_addr32[2] = 0; 900 dst_sa.sin6_addr.s6_addr32[3] = IPV6_ADDR_INT32_ONE; 901 902 flags &= ~ND_NA_FLAG_SOLICITED; 903 } 904 ip6->ip6_dst = dst_sa.sin6_addr; 905 906 /* 907 * Select a source whose scope is the same as that of the dest. 908 */ 909 bcopy(&dst_sa, &ro.ro_dst, sizeof(dst_sa)); 910 src0 = in6_selectsrc(&dst_sa, NULL, NULL, &ro, NULL, &error); 911 if (src0 == NULL) { 912 nd6log((LOG_DEBUG, "nd6_na_output: source can't be " 913 "determined: dst=%s, error=%d\n", 914 ip6_sprintf(&dst_sa.sin6_addr), error)); 915 goto bad; 916 } 917 ip6->ip6_src = *src0; 918 nd_na = (struct nd_neighbor_advert *)(ip6 + 1); 919 nd_na->nd_na_type = ND_NEIGHBOR_ADVERT; 920 nd_na->nd_na_code = 0; 921 nd_na->nd_na_target = *taddr6; 922 if (IN6_IS_SCOPE_LINKLOCAL(&nd_na->nd_na_target)) 923 nd_na->nd_na_target.s6_addr16[1] = 0; 924 925 /* 926 * "tlladdr" indicates NS's condition for adding tlladdr or not. 927 * see nd6_ns_input() for details. 928 * Basically, if NS packet is sent to unicast/anycast addr, 929 * target lladdr option SHOULD NOT be included. 930 */ 931 if (tlladdr) { 932 /* 933 * sdl0 != NULL indicates proxy NA. If we do proxy, use 934 * lladdr in sdl0. If we are not proxying (sending NA for 935 * my address) use lladdr configured for the interface. 936 */ 937 if (sdl0 == NULL) 938 mac = nd6_ifptomac(ifp); 939 else if (sdl0->sa_family == AF_LINK) { 940 struct sockaddr_dl *sdl; 941 sdl = (struct sockaddr_dl *)sdl0; 942 if (sdl->sdl_alen == ifp->if_addrlen) 943 mac = LLADDR(sdl); 944 } 945 } 946 if (tlladdr && mac) { 947 int optlen = sizeof(struct nd_opt_hdr) + ifp->if_addrlen; 948 struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)(nd_na + 1); 949 950 /* roundup to 8 bytes alignment! */ 951 optlen = (optlen + 7) & ~7; 952 953 m->m_pkthdr.len += optlen; 954 m->m_len += optlen; 955 icmp6len += optlen; 956 bzero((caddr_t)nd_opt, optlen); 957 nd_opt->nd_opt_type = ND_OPT_TARGET_LINKADDR; 958 nd_opt->nd_opt_len = optlen >> 3; 959 bcopy(mac, (caddr_t)(nd_opt + 1), ifp->if_addrlen); 960 } else 961 flags &= ~ND_NA_FLAG_OVERRIDE; 962 963 ip6->ip6_plen = htons((u_int16_t)icmp6len); 964 nd_na->nd_na_flags_reserved = flags; 965 nd_na->nd_na_cksum = 0; 966 nd_na->nd_na_cksum = 967 in6_cksum(m, IPPROTO_ICMPV6, sizeof(struct ip6_hdr), icmp6len); 968 969 ip6_output(m, NULL, NULL, 0, &im6o, (struct socket *)NULL, NULL); 970 971 icmp6_ifstat_inc(ifp, ifs6_out_msg); 972 icmp6_ifstat_inc(ifp, ifs6_out_neighboradvert); 973 icmp6stat.icp6s_outhist[ND_NEIGHBOR_ADVERT]++; 974 975 if (ro.ro_rt) { /* we don't cache this route. */ 976 RTFREE(ro.ro_rt); 977 } 978 return; 979 980 bad: 981 if (ro.ro_rt) { 982 RTFREE(ro.ro_rt); 983 } 984 m_freem(m); 985 return; 986 } 987 988 caddr_t 989 nd6_ifptomac(ifp) 990 struct ifnet *ifp; 991 { 992 switch (ifp->if_type) { 993 case IFT_ARCNET: 994 case IFT_ETHER: 995 case IFT_FDDI: 996 case IFT_IEEE1394: 997 case IFT_PROPVIRTUAL: 998 case IFT_L2VLAN: 999 case IFT_IEEE80211: 1000 return LLADDR(ifp->if_sadl); 1001 default: 1002 return NULL; 1003 } 1004 } 1005 1006 TAILQ_HEAD(dadq_head, dadq); 1007 struct dadq { 1008 TAILQ_ENTRY(dadq) dad_list; 1009 struct ifaddr *dad_ifa; 1010 int dad_count; /* max NS to send */ 1011 int dad_ns_tcount; /* # of trials to send NS */ 1012 int dad_ns_ocount; /* NS sent so far */ 1013 int dad_ns_icount; 1014 int dad_na_icount; 1015 struct callout dad_timer_ch; 1016 }; 1017 1018 static struct dadq_head dadq; 1019 static int dad_init = 0; 1020 1021 static struct dadq * 1022 nd6_dad_find(ifa) 1023 struct ifaddr *ifa; 1024 { 1025 struct dadq *dp; 1026 1027 for (dp = dadq.tqh_first; dp; dp = dp->dad_list.tqe_next) { 1028 if (dp->dad_ifa == ifa) 1029 return dp; 1030 } 1031 return NULL; 1032 } 1033 1034 static void 1035 nd6_dad_starttimer(dp, ticks) 1036 struct dadq *dp; 1037 int ticks; 1038 { 1039 1040 callout_reset(&dp->dad_timer_ch, ticks, 1041 (void (*) __P((void *)))nd6_dad_timer, (void *)dp->dad_ifa); 1042 } 1043 1044 static void 1045 nd6_dad_stoptimer(dp) 1046 struct dadq *dp; 1047 { 1048 1049 callout_stop(&dp->dad_timer_ch); 1050 } 1051 1052 /* 1053 * Start Duplicated Address Detection (DAD) for specified interface address. 1054 */ 1055 void 1056 nd6_dad_start(ifa, xtick) 1057 struct ifaddr *ifa; 1058 int *xtick; /* minimum delay ticks for IFF_UP event */ 1059 { 1060 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1061 struct dadq *dp; 1062 1063 if (!dad_init) { 1064 TAILQ_INIT(&dadq); 1065 dad_init++; 1066 } 1067 1068 /* 1069 * If we don't need DAD, don't do it. 1070 * There are several cases: 1071 * - DAD is disabled (ip6_dad_count == 0) 1072 * - the interface address is anycast 1073 */ 1074 if (!(ia->ia6_flags & IN6_IFF_TENTATIVE)) { 1075 log(LOG_DEBUG, 1076 "nd6_dad_start: called with non-tentative address " 1077 "%s(%s)\n", 1078 ip6_sprintf(&ia->ia_addr.sin6_addr), 1079 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1080 return; 1081 } 1082 if (ia->ia6_flags & IN6_IFF_ANYCAST) { 1083 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1084 return; 1085 } 1086 if (!ip6_dad_count) { 1087 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1088 return; 1089 } 1090 if (!ifa->ifa_ifp) 1091 panic("nd6_dad_start: ifa->ifa_ifp == NULL"); 1092 if (!(ifa->ifa_ifp->if_flags & IFF_UP)) 1093 return; 1094 if (nd6_dad_find(ifa) != NULL) { 1095 /* DAD already in progress */ 1096 return; 1097 } 1098 1099 dp = malloc(sizeof(*dp), M_IP6NDP, M_NOWAIT); 1100 if (dp == NULL) { 1101 log(LOG_ERR, "nd6_dad_start: memory allocation failed for " 1102 "%s(%s)\n", 1103 ip6_sprintf(&ia->ia_addr.sin6_addr), 1104 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1105 return; 1106 } 1107 bzero(dp, sizeof(*dp)); 1108 callout_init(&dp->dad_timer_ch); 1109 TAILQ_INSERT_TAIL(&dadq, (struct dadq *)dp, dad_list); 1110 1111 nd6log((LOG_DEBUG, "%s: starting DAD for %s\n", if_name(ifa->ifa_ifp), 1112 ip6_sprintf(&ia->ia_addr.sin6_addr))); 1113 1114 /* 1115 * Send NS packet for DAD, ip6_dad_count times. 1116 * Note that we must delay the first transmission, if this is the 1117 * first packet to be sent from the interface after interface 1118 * (re)initialization. 1119 */ 1120 dp->dad_ifa = ifa; 1121 IFAREF(ifa); /* just for safety */ 1122 dp->dad_count = ip6_dad_count; 1123 dp->dad_ns_icount = dp->dad_na_icount = 0; 1124 dp->dad_ns_ocount = dp->dad_ns_tcount = 0; 1125 if (xtick == NULL) { 1126 nd6_dad_ns_output(dp, ifa); 1127 nd6_dad_starttimer(dp, 1128 (long)ND_IFINFO(ifa->ifa_ifp)->retrans * hz / 1000); 1129 } else { 1130 int ntick; 1131 1132 if (*xtick == 0) 1133 ntick = arc4random() % (MAX_RTR_SOLICITATION_DELAY * hz); 1134 else 1135 ntick = *xtick + arc4random() % (hz / 2); 1136 *xtick = ntick; 1137 nd6_dad_starttimer(dp, ntick); 1138 } 1139 } 1140 1141 /* 1142 * terminate DAD unconditionally. used for address removals. 1143 */ 1144 void 1145 nd6_dad_stop(ifa) 1146 struct ifaddr *ifa; 1147 { 1148 struct dadq *dp; 1149 1150 if (!dad_init) 1151 return; 1152 dp = nd6_dad_find(ifa); 1153 if (!dp) { 1154 /* DAD wasn't started yet */ 1155 return; 1156 } 1157 1158 nd6_dad_stoptimer(dp); 1159 1160 TAILQ_REMOVE(&dadq, (struct dadq *)dp, dad_list); 1161 free(dp, M_IP6NDP); 1162 dp = NULL; 1163 IFAFREE(ifa); 1164 } 1165 1166 static void 1167 nd6_dad_timer(ifa) 1168 struct ifaddr *ifa; 1169 { 1170 int s; 1171 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1172 struct dadq *dp; 1173 1174 s = splsoftnet(); /* XXX */ 1175 1176 /* Sanity check */ 1177 if (ia == NULL) { 1178 log(LOG_ERR, "nd6_dad_timer: called with null parameter\n"); 1179 goto done; 1180 } 1181 dp = nd6_dad_find(ifa); 1182 if (dp == NULL) { 1183 log(LOG_ERR, "nd6_dad_timer: DAD structure not found\n"); 1184 goto done; 1185 } 1186 if (ia->ia6_flags & IN6_IFF_DUPLICATED) { 1187 log(LOG_ERR, "nd6_dad_timer: called with duplicated address " 1188 "%s(%s)\n", 1189 ip6_sprintf(&ia->ia_addr.sin6_addr), 1190 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1191 goto done; 1192 } 1193 if ((ia->ia6_flags & IN6_IFF_TENTATIVE) == 0) { 1194 log(LOG_ERR, "nd6_dad_timer: called with non-tentative 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 1201 /* timeouted with IFF_{RUNNING,UP} check */ 1202 if (dp->dad_ns_tcount > dad_maxtry) { 1203 nd6log((LOG_INFO, "%s: could not run DAD, driver problem?\n", 1204 if_name(ifa->ifa_ifp))); 1205 1206 TAILQ_REMOVE(&dadq, (struct dadq *)dp, dad_list); 1207 free(dp, M_IP6NDP); 1208 dp = NULL; 1209 IFAFREE(ifa); 1210 goto done; 1211 } 1212 1213 /* Need more checks? */ 1214 if (dp->dad_ns_ocount < dp->dad_count) { 1215 /* 1216 * We have more NS to go. Send NS packet for DAD. 1217 */ 1218 nd6_dad_ns_output(dp, ifa); 1219 nd6_dad_starttimer(dp, 1220 (long)ND_IFINFO(ifa->ifa_ifp)->retrans * hz / 1000); 1221 } else { 1222 /* 1223 * We have transmitted sufficient number of DAD packets. 1224 * See what we've got. 1225 */ 1226 int duplicate; 1227 1228 duplicate = 0; 1229 1230 if (dp->dad_na_icount) { 1231 /* 1232 * the check is in nd6_dad_na_input(), 1233 * but just in case 1234 */ 1235 duplicate++; 1236 } 1237 1238 if (dp->dad_ns_icount) { 1239 /* We've seen NS, means DAD has failed. */ 1240 duplicate++; 1241 } 1242 1243 if (duplicate) { 1244 /* (*dp) will be freed in nd6_dad_duplicated() */ 1245 dp = NULL; 1246 nd6_dad_duplicated(ifa); 1247 } else { 1248 /* 1249 * We are done with DAD. No NA came, no NS came. 1250 * duplicated address found. 1251 */ 1252 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1253 1254 nd6log((LOG_DEBUG, 1255 "%s: DAD complete for %s - no duplicates found\n", 1256 if_name(ifa->ifa_ifp), 1257 ip6_sprintf(&ia->ia_addr.sin6_addr))); 1258 1259 TAILQ_REMOVE(&dadq, (struct dadq *)dp, dad_list); 1260 free(dp, M_IP6NDP); 1261 dp = NULL; 1262 IFAFREE(ifa); 1263 } 1264 } 1265 1266 done: 1267 splx(s); 1268 } 1269 1270 void 1271 nd6_dad_duplicated(ifa) 1272 struct ifaddr *ifa; 1273 { 1274 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1275 struct dadq *dp; 1276 1277 dp = nd6_dad_find(ifa); 1278 if (dp == NULL) { 1279 log(LOG_ERR, "nd6_dad_duplicated: DAD structure not found\n"); 1280 return; 1281 } 1282 1283 log(LOG_ERR, "%s: DAD detected duplicate IPv6 address %s: " 1284 "NS in/out=%d/%d, NA in=%d\n", 1285 if_name(ifa->ifa_ifp), ip6_sprintf(&ia->ia_addr.sin6_addr), 1286 dp->dad_ns_icount, dp->dad_ns_ocount, dp->dad_na_icount); 1287 1288 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1289 ia->ia6_flags |= IN6_IFF_DUPLICATED; 1290 1291 /* We are done with DAD, with duplicated address found. (failure) */ 1292 nd6_dad_stoptimer(dp); 1293 1294 log(LOG_ERR, "%s: DAD complete for %s - duplicate found\n", 1295 if_name(ifa->ifa_ifp), ip6_sprintf(&ia->ia_addr.sin6_addr)); 1296 log(LOG_ERR, "%s: manual intervention required\n", 1297 if_name(ifa->ifa_ifp)); 1298 1299 TAILQ_REMOVE(&dadq, (struct dadq *)dp, dad_list); 1300 free(dp, M_IP6NDP); 1301 dp = NULL; 1302 IFAFREE(ifa); 1303 } 1304 1305 static void 1306 nd6_dad_ns_output(dp, ifa) 1307 struct dadq *dp; 1308 struct ifaddr *ifa; 1309 { 1310 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1311 struct ifnet *ifp = ifa->ifa_ifp; 1312 1313 dp->dad_ns_tcount++; 1314 if ((ifp->if_flags & IFF_UP) == 0) { 1315 #if 0 1316 printf("%s: interface down?\n", if_name(ifp)); 1317 #endif 1318 return; 1319 } 1320 if ((ifp->if_flags & IFF_RUNNING) == 0) { 1321 #if 0 1322 printf("%s: interface not running?\n", if_name(ifp)); 1323 #endif 1324 return; 1325 } 1326 1327 dp->dad_ns_ocount++; 1328 nd6_ns_output(ifp, NULL, &ia->ia_addr.sin6_addr, NULL, 1); 1329 } 1330 1331 static void 1332 nd6_dad_ns_input(ifa) 1333 struct ifaddr *ifa; 1334 { 1335 struct in6_ifaddr *ia; 1336 const struct in6_addr *taddr6; 1337 struct dadq *dp; 1338 int duplicate; 1339 1340 if (!ifa) 1341 panic("ifa == NULL in nd6_dad_ns_input"); 1342 1343 ia = (struct in6_ifaddr *)ifa; 1344 taddr6 = &ia->ia_addr.sin6_addr; 1345 duplicate = 0; 1346 dp = nd6_dad_find(ifa); 1347 1348 /* Quickhack - completely ignore DAD NS packets */ 1349 if (dad_ignore_ns) { 1350 nd6log((LOG_INFO, 1351 "nd6_dad_ns_input: ignoring DAD NS packet for " 1352 "address %s(%s)\n", ip6_sprintf(taddr6), 1353 if_name(ifa->ifa_ifp))); 1354 return; 1355 } 1356 1357 /* 1358 * if I'm yet to start DAD, someone else started using this address 1359 * first. I have a duplicate and you win. 1360 */ 1361 if (!dp || dp->dad_ns_ocount == 0) 1362 duplicate++; 1363 1364 /* XXX more checks for loopback situation - see nd6_dad_timer too */ 1365 1366 if (duplicate) { 1367 dp = NULL; /* will be freed in nd6_dad_duplicated() */ 1368 nd6_dad_duplicated(ifa); 1369 } else { 1370 /* 1371 * not sure if I got a duplicate. 1372 * increment ns count and see what happens. 1373 */ 1374 if (dp) 1375 dp->dad_ns_icount++; 1376 } 1377 } 1378 1379 static void 1380 nd6_dad_na_input(ifa) 1381 struct ifaddr *ifa; 1382 { 1383 struct dadq *dp; 1384 1385 if (!ifa) 1386 panic("ifa == NULL in nd6_dad_na_input"); 1387 1388 dp = nd6_dad_find(ifa); 1389 if (dp) 1390 dp->dad_na_icount++; 1391 1392 /* remove the address. */ 1393 nd6_dad_duplicated(ifa); 1394 } 1395