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sys/netinet6/nd6_nbr.c
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1 /* $NetBSD: nd6_nbr.c,v 1.65.8.1 2008/10/03 10:31:59 jdc 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 1.65.8.1 2008/10/03 10:31:59 jdc 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 <netinet6/in6_ifattach.h> 62 #include <netinet/ip6.h> 63 #include <netinet6/ip6_var.h> 64 #include <netinet6/scope6_var.h> 65 #include <netinet6/nd6.h> 66 #include <netinet/icmp6.h> 67 68 #ifdef IPSEC 69 #include <netinet6/ipsec.h> 70 #endif 71 72 #include "carp.h" 73 #if NCARP > 0 74 #include <netinet/ip_carp.h> 75 #endif 76 77 #include <net/net_osdep.h> 78 79 #define SDL(s) ((struct sockaddr_dl *)s) 80 81 struct dadq; 82 static struct dadq *nd6_dad_find __P((struct ifaddr *)); 83 static void nd6_dad_starttimer __P((struct dadq *, int)); 84 static void nd6_dad_stoptimer __P((struct dadq *)); 85 static void nd6_dad_timer __P((struct ifaddr *)); 86 static void nd6_dad_ns_output __P((struct dadq *, struct ifaddr *)); 87 static void nd6_dad_ns_input __P((struct ifaddr *)); 88 static void nd6_dad_na_input __P((struct ifaddr *)); 89 90 static int dad_ignore_ns = 0; /* ignore NS in DAD - specwise incorrect*/ 91 static int dad_maxtry = 15; /* max # of *tries* to transmit DAD packet */ 92 93 /* 94 * Input a Neighbor Solicitation Message. 95 * 96 * Based on RFC 2461 97 * Based on RFC 2462 (duplicate address detection) 98 */ 99 void 100 nd6_ns_input(m, off, icmp6len) 101 struct mbuf *m; 102 int off, icmp6len; 103 { 104 struct ifnet *ifp = m->m_pkthdr.rcvif; 105 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 106 struct nd_neighbor_solicit *nd_ns; 107 struct in6_addr saddr6 = ip6->ip6_src; 108 struct in6_addr daddr6 = ip6->ip6_dst; 109 struct in6_addr taddr6; 110 struct in6_addr myaddr6; 111 char *lladdr = NULL; 112 struct ifaddr *ifa; 113 int lladdrlen = 0; 114 int anycast = 0, proxy = 0, tentative = 0; 115 int router = ip6_forwarding; 116 int tlladdr; 117 union nd_opts ndopts; 118 struct sockaddr_dl *proxydl = NULL; 119 120 IP6_EXTHDR_GET(nd_ns, struct nd_neighbor_solicit *, m, off, icmp6len); 121 if (nd_ns == NULL) { 122 icmp6stat.icp6s_tooshort++; 123 return; 124 } 125 ip6 = mtod(m, struct ip6_hdr *); /* adjust pointer for safety */ 126 taddr6 = nd_ns->nd_ns_target; 127 if (in6_setscope(&taddr6, ifp, NULL) != 0) 128 goto bad; 129 130 if (ip6->ip6_hlim != 255) { 131 nd6log((LOG_ERR, 132 "nd6_ns_input: invalid hlim (%d) from %s to %s on %s\n", 133 ip6->ip6_hlim, ip6_sprintf(&ip6->ip6_src), 134 ip6_sprintf(&ip6->ip6_dst), if_name(ifp))); 135 goto bad; 136 } 137 138 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) { 139 /* dst has to be a solicited node multicast address. */ 140 /* don't check ifindex portion */ 141 if (daddr6.s6_addr16[0] == IPV6_ADDR_INT16_MLL && 142 daddr6.s6_addr32[1] == 0 && 143 daddr6.s6_addr32[2] == IPV6_ADDR_INT32_ONE && 144 daddr6.s6_addr8[12] == 0xff) { 145 ; /* good */ 146 } else { 147 nd6log((LOG_INFO, "nd6_ns_input: bad DAD packet " 148 "(wrong ip6 dst)\n")); 149 goto bad; 150 } 151 } else { 152 /* 153 * Make sure the source address is from a neighbor's address. 154 */ 155 if (in6ifa_ifplocaladdr(ifp, &saddr6) == NULL) { 156 nd6log((LOG_INFO, "nd6_ns_input: " 157 "NS packet from non-neighbor\n")); 158 goto bad; 159 } 160 } 161 162 163 if (IN6_IS_ADDR_MULTICAST(&taddr6)) { 164 nd6log((LOG_INFO, "nd6_ns_input: bad NS target (multicast)\n")); 165 goto bad; 166 } 167 168 icmp6len -= sizeof(*nd_ns); 169 nd6_option_init(nd_ns + 1, icmp6len, &ndopts); 170 if (nd6_options(&ndopts) < 0) { 171 nd6log((LOG_INFO, 172 "nd6_ns_input: invalid ND option, ignored\n")); 173 /* nd6_options have incremented stats */ 174 goto freeit; 175 } 176 177 if (ndopts.nd_opts_src_lladdr) { 178 lladdr = (char *)(ndopts.nd_opts_src_lladdr + 1); 179 lladdrlen = ndopts.nd_opts_src_lladdr->nd_opt_len << 3; 180 } 181 182 if (IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_src) && lladdr) { 183 nd6log((LOG_INFO, "nd6_ns_input: bad DAD packet " 184 "(link-layer address option)\n")); 185 goto bad; 186 } 187 188 /* 189 * Attaching target link-layer address to the NA? 190 * (RFC 2461 7.2.4) 191 * 192 * NS IP dst is multicast MUST add 193 * Otherwise MAY be omitted 194 * 195 * In this implementation, we omit the target link-layer address 196 * in the "MAY" case. 197 */ 198 #if 0 /* too much! */ 199 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &daddr6); 200 if (ifa && (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_ANYCAST)) 201 tlladdr = 0; 202 else 203 #endif 204 if (!IN6_IS_ADDR_MULTICAST(&daddr6)) 205 tlladdr = 0; 206 else 207 tlladdr = 1; 208 209 /* 210 * Target address (taddr6) must be either: 211 * (1) Valid unicast/anycast address for my receiving interface, 212 * (2) Unicast address for which I'm offering proxy service, or 213 * (3) "tentative" address on which DAD is being performed. 214 */ 215 /* (1) and (3) check. */ 216 #if NCARP > 0 217 if (ifp->if_carp && ifp->if_type != IFT_CARP) 218 ifa = carp_iamatch6(ifp->if_carp, &taddr6); 219 else 220 ifa = NULL; 221 if (!ifa) 222 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &taddr6); 223 #else 224 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &taddr6); 225 #endif 226 227 /* (2) check. */ 228 if (ifa == NULL) { 229 struct rtentry *rt; 230 struct sockaddr_in6 tsin6; 231 232 memset(&tsin6, 0, sizeof(tsin6)); 233 tsin6.sin6_len = sizeof(struct sockaddr_in6); 234 tsin6.sin6_family = AF_INET6; 235 tsin6.sin6_addr = taddr6; 236 237 rt = rtalloc1((struct sockaddr *)&tsin6, 0); 238 if (rt && (rt->rt_flags & RTF_ANNOUNCE) != 0 && 239 rt->rt_gateway->sa_family == AF_LINK) { 240 /* 241 * proxy NDP for single entry 242 */ 243 ifa = (struct ifaddr *)in6ifa_ifpforlinklocal(ifp, 244 IN6_IFF_NOTREADY|IN6_IFF_ANYCAST); 245 if (ifa) { 246 proxy = 1; 247 proxydl = SDL(rt->rt_gateway); 248 router = 0; /* XXX */ 249 } 250 } 251 if (rt) 252 rtfree(rt); 253 } 254 if (ifa == NULL) { 255 /* 256 * We've got an NS packet, and we don't have that address 257 * assigned for us. We MUST silently ignore it. 258 * See RFC2461 7.2.3. 259 */ 260 goto freeit; 261 } 262 myaddr6 = *IFA_IN6(ifa); 263 anycast = ((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_ANYCAST; 264 tentative = ((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_TENTATIVE; 265 if (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_DUPLICATED) 266 goto freeit; 267 268 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) { 269 nd6log((LOG_INFO, "nd6_ns_input: lladdrlen mismatch for %s " 270 "(if %d, NS packet %d)\n", 271 ip6_sprintf(&taddr6), ifp->if_addrlen, lladdrlen - 2)); 272 goto bad; 273 } 274 275 if (IN6_ARE_ADDR_EQUAL(&myaddr6, &saddr6)) { 276 nd6log((LOG_INFO, "nd6_ns_input: duplicate IP6 address %s\n", 277 ip6_sprintf(&saddr6))); 278 goto freeit; 279 } 280 281 /* 282 * We have neighbor solicitation packet, with target address equals to 283 * one of my tentative address. 284 * 285 * src addr how to process? 286 * --- --- 287 * multicast of course, invalid (rejected in ip6_input) 288 * unicast somebody is doing address resolution -> ignore 289 * unspec dup address detection 290 * 291 * The processing is defined in RFC 2462. 292 */ 293 if (tentative) { 294 /* 295 * If source address is unspecified address, it is for 296 * duplicate address detection. 297 * 298 * If not, the packet is for addess resolution; 299 * silently ignore it. 300 */ 301 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) 302 nd6_dad_ns_input(ifa); 303 304 goto freeit; 305 } 306 307 /* 308 * If the source address is unspecified address, entries must not 309 * be created or updated. 310 * It looks that sender is performing DAD. Output NA toward 311 * all-node multicast address, to tell the sender that I'm using 312 * the address. 313 * S bit ("solicited") must be zero. 314 */ 315 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) { 316 struct in6_addr in6_all; 317 318 in6_all = in6addr_linklocal_allnodes; 319 if (in6_setscope(&in6_all, ifp, NULL) != 0) 320 goto bad; 321 nd6_na_output(ifp, &in6_all, &taddr6, 322 ((anycast || proxy || !tlladdr) ? 0 : ND_NA_FLAG_OVERRIDE) | 323 (ip6_forwarding ? ND_NA_FLAG_ROUTER : 0), 324 tlladdr, (struct sockaddr *)proxydl); 325 goto freeit; 326 } 327 328 nd6_cache_lladdr(ifp, &saddr6, lladdr, lladdrlen, ND_NEIGHBOR_SOLICIT, 0); 329 330 nd6_na_output(ifp, &saddr6, &taddr6, 331 ((anycast || proxy || !tlladdr) ? 0 : ND_NA_FLAG_OVERRIDE) | 332 (router ? ND_NA_FLAG_ROUTER : 0) | ND_NA_FLAG_SOLICITED, 333 tlladdr, (struct sockaddr *)proxydl); 334 freeit: 335 m_freem(m); 336 return; 337 338 bad: 339 nd6log((LOG_ERR, "nd6_ns_input: src=%s\n", ip6_sprintf(&saddr6))); 340 nd6log((LOG_ERR, "nd6_ns_input: dst=%s\n", ip6_sprintf(&daddr6))); 341 nd6log((LOG_ERR, "nd6_ns_input: tgt=%s\n", ip6_sprintf(&taddr6))); 342 icmp6stat.icp6s_badns++; 343 m_freem(m); 344 } 345 346 /* 347 * Output a Neighbor Solicitation Message. Caller specifies: 348 * - ICMP6 header source IP6 address 349 * - ND6 header target IP6 address 350 * - ND6 header source datalink address 351 * 352 * Based on RFC 2461 353 * Based on RFC 2462 (duplicate address detection) 354 */ 355 void 356 nd6_ns_output(ifp, daddr6, taddr6, ln, dad) 357 struct ifnet *ifp; 358 const struct in6_addr *daddr6, *taddr6; 359 struct llinfo_nd6 *ln; /* for source address determination */ 360 int dad; /* duplicate address detection */ 361 { 362 struct mbuf *m; 363 struct ip6_hdr *ip6; 364 struct nd_neighbor_solicit *nd_ns; 365 struct in6_addr *src, src_in; 366 struct ip6_moptions im6o; 367 int icmp6len; 368 int maxlen; 369 caddr_t mac; 370 struct route_in6 ro; 371 372 bzero(&ro, sizeof(ro)); 373 374 if (IN6_IS_ADDR_MULTICAST(taddr6)) 375 return; 376 377 /* estimate the size of message */ 378 maxlen = sizeof(*ip6) + sizeof(*nd_ns); 379 maxlen += (sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7; 380 #ifdef DIAGNOSTIC 381 if (max_linkhdr + maxlen >= MCLBYTES) { 382 printf("nd6_ns_output: max_linkhdr + maxlen >= MCLBYTES " 383 "(%d + %d > %d)\n", max_linkhdr, maxlen, MCLBYTES); 384 panic("nd6_ns_output: insufficient MCLBYTES"); 385 /* NOTREACHED */ 386 } 387 #endif 388 389 MGETHDR(m, M_DONTWAIT, MT_DATA); 390 if (m && max_linkhdr + maxlen >= MHLEN) { 391 MCLGET(m, M_DONTWAIT); 392 if ((m->m_flags & M_EXT) == 0) { 393 m_free(m); 394 m = NULL; 395 } 396 } 397 if (m == NULL) 398 return; 399 m->m_pkthdr.rcvif = NULL; 400 401 if (daddr6 == NULL || IN6_IS_ADDR_MULTICAST(daddr6)) { 402 m->m_flags |= M_MCAST; 403 im6o.im6o_multicast_ifp = ifp; 404 im6o.im6o_multicast_hlim = 255; 405 im6o.im6o_multicast_loop = 0; 406 } 407 408 icmp6len = sizeof(*nd_ns); 409 m->m_pkthdr.len = m->m_len = sizeof(*ip6) + icmp6len; 410 m->m_data += max_linkhdr; /* or MH_ALIGN() equivalent? */ 411 412 /* fill neighbor solicitation packet */ 413 ip6 = mtod(m, struct ip6_hdr *); 414 ip6->ip6_flow = 0; 415 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 416 ip6->ip6_vfc |= IPV6_VERSION; 417 /* ip6->ip6_plen will be set later */ 418 ip6->ip6_nxt = IPPROTO_ICMPV6; 419 ip6->ip6_hlim = 255; 420 if (daddr6) 421 ip6->ip6_dst = *daddr6; 422 else { 423 ip6->ip6_dst.s6_addr16[0] = IPV6_ADDR_INT16_MLL; 424 ip6->ip6_dst.s6_addr16[1] = 0; 425 ip6->ip6_dst.s6_addr32[1] = 0; 426 ip6->ip6_dst.s6_addr32[2] = IPV6_ADDR_INT32_ONE; 427 ip6->ip6_dst.s6_addr32[3] = taddr6->s6_addr32[3]; 428 ip6->ip6_dst.s6_addr8[12] = 0xff; 429 if (in6_setscope(&ip6->ip6_dst, ifp, NULL) != 0) 430 goto bad; 431 } 432 if (!dad) { 433 /* 434 * RFC2461 7.2.2: 435 * "If the source address of the packet prompting the 436 * solicitation is the same as one of the addresses assigned 437 * to the outgoing interface, that address SHOULD be placed 438 * in the IP Source Address of the outgoing solicitation. 439 * Otherwise, any one of the addresses assigned to the 440 * interface should be used." 441 * 442 * We use the source address for the prompting packet 443 * (hsrc), if: 444 * - hsrc is given from the caller (by giving "ln"), and 445 * - hsrc belongs to the outgoing interface. 446 * Otherwise, we perform the source address selection as usual. 447 */ 448 struct ip6_hdr *hip6; /* hold ip6 */ 449 struct in6_addr *hsrc = NULL; 450 451 if (ln && ln->ln_hold) { 452 /* 453 * assuming every packet in ln_hold has the same IP 454 * header 455 */ 456 hip6 = mtod(ln->ln_hold, struct ip6_hdr *); 457 /* XXX pullup? */ 458 if (sizeof(*hip6) < ln->ln_hold->m_len) 459 hsrc = &hip6->ip6_src; 460 else 461 hsrc = NULL; 462 } 463 if (hsrc && in6ifa_ifpwithaddr(ifp, hsrc)) 464 src = hsrc; 465 else { 466 int error; 467 struct sockaddr_in6 dst_sa; 468 469 bzero(&dst_sa, sizeof(dst_sa)); 470 dst_sa.sin6_family = AF_INET6; 471 dst_sa.sin6_len = sizeof(dst_sa); 472 dst_sa.sin6_addr = ip6->ip6_dst; 473 474 src = in6_selectsrc(&dst_sa, NULL, 475 NULL, &ro, NULL, NULL, &error); 476 if (src == NULL) { 477 nd6log((LOG_DEBUG, 478 "nd6_ns_output: source can't be " 479 "determined: dst=%s, error=%d\n", 480 ip6_sprintf(&dst_sa.sin6_addr), error)); 481 goto bad; 482 } 483 } 484 } else { 485 /* 486 * Source address for DAD packet must always be IPv6 487 * unspecified address. (0::0) 488 * We actually don't have to 0-clear the address (we did it 489 * above), but we do so here explicitly to make the intention 490 * clearer. 491 */ 492 bzero(&src_in, sizeof(src_in)); 493 src = &src_in; 494 } 495 ip6->ip6_src = *src; 496 nd_ns = (struct nd_neighbor_solicit *)(ip6 + 1); 497 nd_ns->nd_ns_type = ND_NEIGHBOR_SOLICIT; 498 nd_ns->nd_ns_code = 0; 499 nd_ns->nd_ns_reserved = 0; 500 nd_ns->nd_ns_target = *taddr6; 501 in6_clearscope(&nd_ns->nd_ns_target); /* XXX */ 502 503 /* 504 * Add source link-layer address option. 505 * 506 * spec implementation 507 * --- --- 508 * DAD packet MUST NOT do not add the option 509 * there's no link layer address: 510 * impossible do not add the option 511 * there's link layer address: 512 * Multicast NS MUST add one add the option 513 * Unicast NS SHOULD add one add the option 514 */ 515 if (!dad && (mac = nd6_ifptomac(ifp))) { 516 int optlen = sizeof(struct nd_opt_hdr) + ifp->if_addrlen; 517 struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)(nd_ns + 1); 518 /* 8 byte alignments... */ 519 optlen = (optlen + 7) & ~7; 520 521 m->m_pkthdr.len += optlen; 522 m->m_len += optlen; 523 icmp6len += optlen; 524 bzero((caddr_t)nd_opt, optlen); 525 nd_opt->nd_opt_type = ND_OPT_SOURCE_LINKADDR; 526 nd_opt->nd_opt_len = optlen >> 3; 527 bcopy(mac, (caddr_t)(nd_opt + 1), ifp->if_addrlen); 528 } 529 530 ip6->ip6_plen = htons((u_int16_t)icmp6len); 531 nd_ns->nd_ns_cksum = 0; 532 nd_ns->nd_ns_cksum = 533 in6_cksum(m, IPPROTO_ICMPV6, sizeof(*ip6), icmp6len); 534 535 ip6_output(m, NULL, &ro, dad ? IPV6_UNSPECSRC : 0, &im6o, NULL, NULL); 536 icmp6_ifstat_inc(ifp, ifs6_out_msg); 537 icmp6_ifstat_inc(ifp, ifs6_out_neighborsolicit); 538 icmp6stat.icp6s_outhist[ND_NEIGHBOR_SOLICIT]++; 539 540 if (ro.ro_rt) { /* we don't cache this route. */ 541 RTFREE(ro.ro_rt); 542 } 543 return; 544 545 bad: 546 if (ro.ro_rt) { 547 RTFREE(ro.ro_rt); 548 } 549 m_freem(m); 550 return; 551 } 552 553 /* 554 * Neighbor advertisement input handling. 555 * 556 * Based on RFC 2461 557 * Based on RFC 2462 (duplicate address detection) 558 * 559 * the following items are not implemented yet: 560 * - proxy advertisement delay rule (RFC2461 7.2.8, last paragraph, SHOULD) 561 * - anycast advertisement delay rule (RFC2461 7.2.7, SHOULD) 562 */ 563 void 564 nd6_na_input(m, off, icmp6len) 565 struct mbuf *m; 566 int off, icmp6len; 567 { 568 struct ifnet *ifp = m->m_pkthdr.rcvif; 569 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 570 struct nd_neighbor_advert *nd_na; 571 struct in6_addr saddr6 = ip6->ip6_src; 572 struct in6_addr daddr6 = ip6->ip6_dst; 573 struct in6_addr taddr6; 574 int flags; 575 int is_router; 576 int is_solicited; 577 int is_override; 578 char *lladdr = NULL; 579 int lladdrlen = 0; 580 struct ifaddr *ifa; 581 struct llinfo_nd6 *ln; 582 struct rtentry *rt; 583 struct sockaddr_dl *sdl; 584 union nd_opts ndopts; 585 586 if (ip6->ip6_hlim != 255) { 587 nd6log((LOG_ERR, 588 "nd6_na_input: invalid hlim (%d) from %s to %s on %s\n", 589 ip6->ip6_hlim, ip6_sprintf(&ip6->ip6_src), 590 ip6_sprintf(&ip6->ip6_dst), if_name(ifp))); 591 goto bad; 592 } 593 594 IP6_EXTHDR_GET(nd_na, struct nd_neighbor_advert *, m, off, icmp6len); 595 if (nd_na == NULL) { 596 icmp6stat.icp6s_tooshort++; 597 return; 598 } 599 600 flags = nd_na->nd_na_flags_reserved; 601 is_router = ((flags & ND_NA_FLAG_ROUTER) != 0); 602 is_solicited = ((flags & ND_NA_FLAG_SOLICITED) != 0); 603 is_override = ((flags & ND_NA_FLAG_OVERRIDE) != 0); 604 605 taddr6 = nd_na->nd_na_target; 606 if (in6_setscope(&taddr6, ifp, NULL)) 607 return; /* XXX: impossible */ 608 609 if (IN6_IS_ADDR_MULTICAST(&taddr6)) { 610 nd6log((LOG_ERR, 611 "nd6_na_input: invalid target address %s\n", 612 ip6_sprintf(&taddr6))); 613 goto bad; 614 } 615 if (is_solicited && IN6_IS_ADDR_MULTICAST(&daddr6)) { 616 nd6log((LOG_ERR, 617 "nd6_na_input: a solicited adv is multicasted\n")); 618 goto bad; 619 } 620 621 icmp6len -= sizeof(*nd_na); 622 nd6_option_init(nd_na + 1, icmp6len, &ndopts); 623 if (nd6_options(&ndopts) < 0) { 624 nd6log((LOG_INFO, 625 "nd6_na_input: invalid ND option, ignored\n")); 626 /* nd6_options have incremented stats */ 627 goto freeit; 628 } 629 630 if (ndopts.nd_opts_tgt_lladdr) { 631 lladdr = (char *)(ndopts.nd_opts_tgt_lladdr + 1); 632 lladdrlen = ndopts.nd_opts_tgt_lladdr->nd_opt_len << 3; 633 } 634 635 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &taddr6); 636 637 /* 638 * Target address matches one of my interface address. 639 * 640 * If my address is tentative, this means that there's somebody 641 * already using the same address as mine. This indicates DAD failure. 642 * This is defined in RFC 2462. 643 * 644 * Otherwise, process as defined in RFC 2461. 645 */ 646 if (ifa 647 && (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_TENTATIVE)) { 648 nd6_dad_na_input(ifa); 649 goto freeit; 650 } 651 652 /* Just for safety, maybe unnecessary. */ 653 if (ifa) { 654 log(LOG_ERR, 655 "nd6_na_input: duplicate IP6 address %s\n", 656 ip6_sprintf(&taddr6)); 657 goto freeit; 658 } 659 /* 660 * Make sure the source address is from a neighbor's address. 661 */ 662 if (in6ifa_ifplocaladdr(ifp, &saddr6) == NULL) { 663 nd6log((LOG_INFO, "nd6_ns_input: " 664 "ND packet from non-neighbor\n")); 665 goto bad; 666 } 667 668 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) { 669 nd6log((LOG_INFO, "nd6_na_input: lladdrlen mismatch for %s " 670 "(if %d, NA packet %d)\n", ip6_sprintf(&taddr6), 671 ifp->if_addrlen, lladdrlen - 2)); 672 goto bad; 673 } 674 675 /* 676 * If no neighbor cache entry is found, NA SHOULD silently be 677 * discarded. 678 */ 679 rt = nd6_lookup(&taddr6, 0, ifp); 680 if ((rt == NULL) || 681 ((ln = (struct llinfo_nd6 *)rt->rt_llinfo) == NULL) || 682 ((sdl = SDL(rt->rt_gateway)) == NULL)) 683 goto freeit; 684 685 if (ln->ln_state == ND6_LLINFO_INCOMPLETE) { 686 /* 687 * If the link-layer has address, and no lladdr option came, 688 * discard the packet. 689 */ 690 if (ifp->if_addrlen && !lladdr) 691 goto freeit; 692 693 /* 694 * Record link-layer address, and update the state. 695 */ 696 sdl->sdl_alen = ifp->if_addrlen; 697 bcopy(lladdr, LLADDR(sdl), ifp->if_addrlen); 698 if (is_solicited) { 699 ln->ln_state = ND6_LLINFO_REACHABLE; 700 ln->ln_byhint = 0; 701 if (!ND6_LLINFO_PERMANENT(ln)) { 702 nd6_llinfo_settimer(ln, 703 (long)ND_IFINFO(rt->rt_ifp)->reachable * hz); 704 } 705 } else { 706 ln->ln_state = ND6_LLINFO_STALE; 707 nd6_llinfo_settimer(ln, (long)nd6_gctimer * hz); 708 } 709 if ((ln->ln_router = is_router) != 0) { 710 /* 711 * This means a router's state has changed from 712 * non-reachable to probably reachable, and might 713 * affect the status of associated prefixes.. 714 */ 715 pfxlist_onlink_check(); 716 } 717 } else { 718 int llchange; 719 720 /* 721 * Check if the link-layer address has changed or not. 722 */ 723 if (lladdr == NULL) 724 llchange = 0; 725 else { 726 if (sdl->sdl_alen) { 727 if (bcmp(lladdr, LLADDR(sdl), ifp->if_addrlen)) 728 llchange = 1; 729 else 730 llchange = 0; 731 } else 732 llchange = 1; 733 } 734 735 /* 736 * This is VERY complex. Look at it with care. 737 * 738 * override solicit lladdr llchange action 739 * (L: record lladdr) 740 * 741 * 0 0 n -- (2c) 742 * 0 0 y n (2b) L 743 * 0 0 y y (1) REACHABLE->STALE 744 * 0 1 n -- (2c) *->REACHABLE 745 * 0 1 y n (2b) L *->REACHABLE 746 * 0 1 y y (1) REACHABLE->STALE 747 * 1 0 n -- (2a) 748 * 1 0 y n (2a) L 749 * 1 0 y y (2a) L *->STALE 750 * 1 1 n -- (2a) *->REACHABLE 751 * 1 1 y n (2a) L *->REACHABLE 752 * 1 1 y y (2a) L *->REACHABLE 753 */ 754 if (!is_override && lladdr != NULL && llchange) { /* (1) */ 755 /* 756 * If state is REACHABLE, make it STALE. 757 * no other updates should be done. 758 */ 759 if (ln->ln_state == ND6_LLINFO_REACHABLE) { 760 ln->ln_state = ND6_LLINFO_STALE; 761 nd6_llinfo_settimer(ln, (long)nd6_gctimer * hz); 762 } 763 goto freeit; 764 } else if (is_override /* (2a) */ 765 || (!is_override && lladdr != NULL && !llchange) /* (2b) */ 766 || lladdr == NULL) { /* (2c) */ 767 /* 768 * Update link-local address, if any. 769 */ 770 if (lladdr != NULL) { 771 sdl->sdl_alen = ifp->if_addrlen; 772 bcopy(lladdr, LLADDR(sdl), ifp->if_addrlen); 773 } 774 775 /* 776 * If solicited, make the state REACHABLE. 777 * If not solicited and the link-layer address was 778 * changed, make it STALE. 779 */ 780 if (is_solicited) { 781 ln->ln_state = ND6_LLINFO_REACHABLE; 782 ln->ln_byhint = 0; 783 if (!ND6_LLINFO_PERMANENT(ln)) { 784 nd6_llinfo_settimer(ln, 785 (long)ND_IFINFO(ifp)->reachable * hz); 786 } 787 } else { 788 if (lladdr && llchange) { 789 ln->ln_state = ND6_LLINFO_STALE; 790 nd6_llinfo_settimer(ln, 791 (long)nd6_gctimer * hz); 792 } 793 } 794 } 795 796 if (ln->ln_router && !is_router) { 797 /* 798 * The peer dropped the router flag. 799 * Remove the sender from the Default Router List and 800 * update the Destination Cache entries. 801 */ 802 struct nd_defrouter *dr; 803 struct in6_addr *in6; 804 int s; 805 806 in6 = &((struct sockaddr_in6 *)rt_key(rt))->sin6_addr; 807 808 /* 809 * Lock to protect the default router list. 810 * XXX: this might be unnecessary, since this function 811 * is only called under the network software interrupt 812 * context. However, we keep it just for safety. 813 */ 814 s = splsoftnet(); 815 dr = defrouter_lookup(in6, rt->rt_ifp); 816 if (dr) 817 defrtrlist_del(dr); 818 else if (!ip6_forwarding) { 819 /* 820 * Even if the neighbor is not in the default 821 * router list, the neighbor may be used 822 * as a next hop for some destinations 823 * (e.g. redirect case). So we must 824 * call rt6_flush explicitly. 825 */ 826 rt6_flush(&ip6->ip6_src, rt->rt_ifp); 827 } 828 splx(s); 829 } 830 ln->ln_router = is_router; 831 } 832 rt->rt_flags &= ~RTF_REJECT; 833 ln->ln_asked = 0; 834 if (ln->ln_hold) { 835 struct mbuf *m_hold, *m_hold_next; 836 837 for (m_hold = ln->ln_hold; m_hold; m_hold = m_hold_next) { 838 struct mbuf *mpkt = NULL; 839 840 m_hold_next = m_hold->m_nextpkt; 841 mpkt = m_copym(m_hold, 0, M_COPYALL, M_DONTWAIT); 842 if (mpkt == NULL) { 843 m_freem(m_hold); 844 break; 845 } 846 mpkt->m_nextpkt = NULL; 847 /* 848 * we assume ifp is not a loopback here, so just set 849 * the 2nd argument as the 1st one. 850 */ 851 nd6_output(ifp, ifp, mpkt, 852 (struct sockaddr_in6 *)rt_key(rt), rt); 853 } 854 ln->ln_hold = NULL; 855 } 856 857 freeit: 858 m_freem(m); 859 return; 860 861 bad: 862 icmp6stat.icp6s_badna++; 863 m_freem(m); 864 } 865 866 /* 867 * Neighbor advertisement output handling. 868 * 869 * Based on RFC 2461 870 * 871 * the following items are not implemented yet: 872 * - proxy advertisement delay rule (RFC2461 7.2.8, last paragraph, SHOULD) 873 * - anycast advertisement delay rule (RFC2461 7.2.7, SHOULD) 874 */ 875 void 876 nd6_na_output(ifp, daddr6_0, taddr6, flags, tlladdr, sdl0) 877 struct ifnet *ifp; 878 const struct in6_addr *daddr6_0, *taddr6; 879 u_long flags; 880 int tlladdr; /* 1 if include target link-layer address */ 881 struct sockaddr *sdl0; /* sockaddr_dl (= proxy NA) or NULL */ 882 { 883 struct mbuf *m; 884 struct ip6_hdr *ip6; 885 struct nd_neighbor_advert *nd_na; 886 struct ip6_moptions im6o; 887 struct sockaddr_in6 dst_sa; 888 struct in6_addr *src, daddr6; 889 int icmp6len, maxlen, error; 890 caddr_t mac; 891 struct route_in6 ro; 892 893 mac = NULL; 894 bzero(&ro, sizeof(ro)); 895 896 daddr6 = *daddr6_0; /* make a local copy for modification */ 897 898 /* estimate the size of message */ 899 maxlen = sizeof(*ip6) + sizeof(*nd_na); 900 maxlen += (sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7; 901 #ifdef DIAGNOSTIC 902 if (max_linkhdr + maxlen >= MCLBYTES) { 903 printf("nd6_na_output: max_linkhdr + maxlen >= MCLBYTES " 904 "(%d + %d > %d)\n", max_linkhdr, maxlen, MCLBYTES); 905 panic("nd6_na_output: insufficient MCLBYTES"); 906 /* NOTREACHED */ 907 } 908 #endif 909 910 MGETHDR(m, M_DONTWAIT, MT_DATA); 911 if (m && max_linkhdr + maxlen >= MHLEN) { 912 MCLGET(m, M_DONTWAIT); 913 if ((m->m_flags & M_EXT) == 0) { 914 m_free(m); 915 m = NULL; 916 } 917 } 918 if (m == NULL) 919 return; 920 m->m_pkthdr.rcvif = NULL; 921 922 if (IN6_IS_ADDR_MULTICAST(&daddr6)) { 923 m->m_flags |= M_MCAST; 924 im6o.im6o_multicast_ifp = ifp; 925 im6o.im6o_multicast_hlim = 255; 926 im6o.im6o_multicast_loop = 0; 927 } 928 929 icmp6len = sizeof(*nd_na); 930 m->m_pkthdr.len = m->m_len = sizeof(struct ip6_hdr) + icmp6len; 931 m->m_data += max_linkhdr; /* or MH_ALIGN() equivalent? */ 932 933 /* fill neighbor advertisement packet */ 934 ip6 = mtod(m, struct ip6_hdr *); 935 ip6->ip6_flow = 0; 936 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 937 ip6->ip6_vfc |= IPV6_VERSION; 938 ip6->ip6_nxt = IPPROTO_ICMPV6; 939 ip6->ip6_hlim = 255; 940 if (IN6_IS_ADDR_UNSPECIFIED(&daddr6)) { 941 /* reply to DAD */ 942 daddr6.s6_addr16[0] = IPV6_ADDR_INT16_MLL; 943 daddr6.s6_addr16[1] = 0; 944 daddr6.s6_addr32[1] = 0; 945 daddr6.s6_addr32[2] = 0; 946 daddr6.s6_addr32[3] = IPV6_ADDR_INT32_ONE; 947 if (in6_setscope(&daddr6, ifp, NULL)) 948 goto bad; 949 950 flags &= ~ND_NA_FLAG_SOLICITED; 951 } 952 ip6->ip6_dst = daddr6; 953 bzero(&dst_sa, sizeof(struct sockaddr_in6)); 954 dst_sa.sin6_family = AF_INET6; 955 dst_sa.sin6_len = sizeof(struct sockaddr_in6); 956 dst_sa.sin6_addr = daddr6; 957 958 /* 959 * Select a source whose scope is the same as that of the dest. 960 */ 961 bcopy(&dst_sa, &ro.ro_dst, sizeof(dst_sa)); 962 src = in6_selectsrc(&dst_sa, NULL, NULL, &ro, NULL, NULL, &error); 963 if (src == NULL) { 964 nd6log((LOG_DEBUG, "nd6_na_output: source can't be " 965 "determined: dst=%s, error=%d\n", 966 ip6_sprintf(&dst_sa.sin6_addr), error)); 967 goto bad; 968 } 969 ip6->ip6_src = *src; 970 nd_na = (struct nd_neighbor_advert *)(ip6 + 1); 971 nd_na->nd_na_type = ND_NEIGHBOR_ADVERT; 972 nd_na->nd_na_code = 0; 973 nd_na->nd_na_target = *taddr6; 974 in6_clearscope(&nd_na->nd_na_target); /* XXX */ 975 976 /* 977 * "tlladdr" indicates NS's condition for adding tlladdr or not. 978 * see nd6_ns_input() for details. 979 * Basically, if NS packet is sent to unicast/anycast addr, 980 * target lladdr option SHOULD NOT be included. 981 */ 982 if (tlladdr) { 983 /* 984 * sdl0 != NULL indicates proxy NA. If we do proxy, use 985 * lladdr in sdl0. If we are not proxying (sending NA for 986 * my address) use lladdr configured for the interface. 987 */ 988 if (sdl0 == NULL) 989 mac = nd6_ifptomac(ifp); 990 else if (sdl0->sa_family == AF_LINK) { 991 struct sockaddr_dl *sdl; 992 sdl = (struct sockaddr_dl *)sdl0; 993 if (sdl->sdl_alen == ifp->if_addrlen) 994 mac = LLADDR(sdl); 995 } 996 } 997 if (tlladdr && mac) { 998 int optlen = sizeof(struct nd_opt_hdr) + ifp->if_addrlen; 999 struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)(nd_na + 1); 1000 1001 /* roundup to 8 bytes alignment! */ 1002 optlen = (optlen + 7) & ~7; 1003 1004 m->m_pkthdr.len += optlen; 1005 m->m_len += optlen; 1006 icmp6len += optlen; 1007 bzero((caddr_t)nd_opt, optlen); 1008 nd_opt->nd_opt_type = ND_OPT_TARGET_LINKADDR; 1009 nd_opt->nd_opt_len = optlen >> 3; 1010 bcopy(mac, (caddr_t)(nd_opt + 1), ifp->if_addrlen); 1011 } else 1012 flags &= ~ND_NA_FLAG_OVERRIDE; 1013 1014 ip6->ip6_plen = htons((u_int16_t)icmp6len); 1015 nd_na->nd_na_flags_reserved = flags; 1016 nd_na->nd_na_cksum = 0; 1017 nd_na->nd_na_cksum = 1018 in6_cksum(m, IPPROTO_ICMPV6, sizeof(struct ip6_hdr), icmp6len); 1019 1020 ip6_output(m, NULL, NULL, 0, &im6o, (struct socket *)NULL, NULL); 1021 1022 icmp6_ifstat_inc(ifp, ifs6_out_msg); 1023 icmp6_ifstat_inc(ifp, ifs6_out_neighboradvert); 1024 icmp6stat.icp6s_outhist[ND_NEIGHBOR_ADVERT]++; 1025 1026 if (ro.ro_rt) { /* we don't cache this route. */ 1027 RTFREE(ro.ro_rt); 1028 } 1029 return; 1030 1031 bad: 1032 if (ro.ro_rt) { 1033 RTFREE(ro.ro_rt); 1034 } 1035 m_freem(m); 1036 return; 1037 } 1038 1039 caddr_t 1040 nd6_ifptomac(ifp) 1041 struct ifnet *ifp; 1042 { 1043 switch (ifp->if_type) { 1044 case IFT_ARCNET: 1045 case IFT_ETHER: 1046 case IFT_FDDI: 1047 case IFT_IEEE1394: 1048 case IFT_PROPVIRTUAL: 1049 case IFT_CARP: 1050 case IFT_L2VLAN: 1051 case IFT_IEEE80211: 1052 return LLADDR(ifp->if_sadl); 1053 default: 1054 return NULL; 1055 } 1056 } 1057 1058 TAILQ_HEAD(dadq_head, dadq); 1059 struct dadq { 1060 TAILQ_ENTRY(dadq) dad_list; 1061 struct ifaddr *dad_ifa; 1062 int dad_count; /* max NS to send */ 1063 int dad_ns_tcount; /* # of trials to send NS */ 1064 int dad_ns_ocount; /* NS sent so far */ 1065 int dad_ns_icount; 1066 int dad_na_icount; 1067 struct callout dad_timer_ch; 1068 }; 1069 1070 static struct dadq_head dadq; 1071 static int dad_init = 0; 1072 1073 static struct dadq * 1074 nd6_dad_find(ifa) 1075 struct ifaddr *ifa; 1076 { 1077 struct dadq *dp; 1078 1079 for (dp = dadq.tqh_first; dp; dp = dp->dad_list.tqe_next) { 1080 if (dp->dad_ifa == ifa) 1081 return dp; 1082 } 1083 return NULL; 1084 } 1085 1086 static void 1087 nd6_dad_starttimer(dp, ticks) 1088 struct dadq *dp; 1089 int ticks; 1090 { 1091 1092 callout_reset(&dp->dad_timer_ch, ticks, 1093 (void (*) __P((void *)))nd6_dad_timer, (void *)dp->dad_ifa); 1094 } 1095 1096 static void 1097 nd6_dad_stoptimer(dp) 1098 struct dadq *dp; 1099 { 1100 1101 callout_stop(&dp->dad_timer_ch); 1102 } 1103 1104 /* 1105 * Start Duplicate Address Detection (DAD) for specified interface address. 1106 */ 1107 void 1108 nd6_dad_start(ifa, xtick) 1109 struct ifaddr *ifa; 1110 int xtick; /* minimum delay ticks for IFF_UP event */ 1111 { 1112 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1113 struct dadq *dp; 1114 1115 if (!dad_init) { 1116 TAILQ_INIT(&dadq); 1117 dad_init++; 1118 } 1119 1120 /* 1121 * If we don't need DAD, don't do it. 1122 * There are several cases: 1123 * - DAD is disabled (ip6_dad_count == 0) 1124 * - the interface address is anycast 1125 */ 1126 if (!(ia->ia6_flags & IN6_IFF_TENTATIVE)) { 1127 log(LOG_DEBUG, 1128 "nd6_dad_start: called with non-tentative address " 1129 "%s(%s)\n", 1130 ip6_sprintf(&ia->ia_addr.sin6_addr), 1131 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1132 return; 1133 } 1134 if (ia->ia6_flags & IN6_IFF_ANYCAST) { 1135 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1136 return; 1137 } 1138 if (!ip6_dad_count) { 1139 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1140 return; 1141 } 1142 if (ifa->ifa_ifp == NULL) 1143 panic("nd6_dad_start: ifa->ifa_ifp == NULL"); 1144 if (!(ifa->ifa_ifp->if_flags & IFF_UP)) 1145 return; 1146 if (nd6_dad_find(ifa) != NULL) { 1147 /* DAD already in progress */ 1148 return; 1149 } 1150 1151 dp = malloc(sizeof(*dp), M_IP6NDP, M_NOWAIT); 1152 if (dp == NULL) { 1153 log(LOG_ERR, "nd6_dad_start: memory allocation failed for " 1154 "%s(%s)\n", 1155 ip6_sprintf(&ia->ia_addr.sin6_addr), 1156 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1157 return; 1158 } 1159 bzero(dp, sizeof(*dp)); 1160 callout_init(&dp->dad_timer_ch); 1161 TAILQ_INSERT_TAIL(&dadq, (struct dadq *)dp, dad_list); 1162 1163 nd6log((LOG_DEBUG, "%s: starting DAD for %s\n", if_name(ifa->ifa_ifp), 1164 ip6_sprintf(&ia->ia_addr.sin6_addr))); 1165 1166 /* 1167 * Send NS packet for DAD, ip6_dad_count times. 1168 * Note that we must delay the first transmission, if this is the 1169 * first packet to be sent from the interface after interface 1170 * (re)initialization. 1171 */ 1172 dp->dad_ifa = ifa; 1173 IFAREF(ifa); /* just for safety */ 1174 dp->dad_count = ip6_dad_count; 1175 dp->dad_ns_icount = dp->dad_na_icount = 0; 1176 dp->dad_ns_ocount = dp->dad_ns_tcount = 0; 1177 if (xtick == 0) { 1178 nd6_dad_ns_output(dp, ifa); 1179 nd6_dad_starttimer(dp, 1180 (long)ND_IFINFO(ifa->ifa_ifp)->retrans * hz / 1000); 1181 } else 1182 nd6_dad_starttimer(dp, xtick); 1183 } 1184 1185 /* 1186 * terminate DAD unconditionally. used for address removals. 1187 */ 1188 void 1189 nd6_dad_stop(ifa) 1190 struct ifaddr *ifa; 1191 { 1192 struct dadq *dp; 1193 1194 if (!dad_init) 1195 return; 1196 dp = nd6_dad_find(ifa); 1197 if (dp == NULL) { 1198 /* DAD wasn't started yet */ 1199 return; 1200 } 1201 1202 nd6_dad_stoptimer(dp); 1203 1204 TAILQ_REMOVE(&dadq, (struct dadq *)dp, dad_list); 1205 free(dp, M_IP6NDP); 1206 dp = NULL; 1207 IFAFREE(ifa); 1208 } 1209 1210 static void 1211 nd6_dad_timer(ifa) 1212 struct ifaddr *ifa; 1213 { 1214 int s; 1215 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1216 struct dadq *dp; 1217 1218 s = splsoftnet(); /* XXX */ 1219 1220 /* Sanity check */ 1221 if (ia == NULL) { 1222 log(LOG_ERR, "nd6_dad_timer: called with null parameter\n"); 1223 goto done; 1224 } 1225 dp = nd6_dad_find(ifa); 1226 if (dp == NULL) { 1227 log(LOG_ERR, "nd6_dad_timer: DAD structure not found\n"); 1228 goto done; 1229 } 1230 if (ia->ia6_flags & IN6_IFF_DUPLICATED) { 1231 log(LOG_ERR, "nd6_dad_timer: called with duplicate address " 1232 "%s(%s)\n", 1233 ip6_sprintf(&ia->ia_addr.sin6_addr), 1234 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1235 goto done; 1236 } 1237 if ((ia->ia6_flags & IN6_IFF_TENTATIVE) == 0) { 1238 log(LOG_ERR, "nd6_dad_timer: called with non-tentative address " 1239 "%s(%s)\n", 1240 ip6_sprintf(&ia->ia_addr.sin6_addr), 1241 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1242 goto done; 1243 } 1244 1245 /* timeouted with IFF_{RUNNING,UP} check */ 1246 if (dp->dad_ns_tcount > dad_maxtry) { 1247 nd6log((LOG_INFO, "%s: could not run DAD, driver problem?\n", 1248 if_name(ifa->ifa_ifp))); 1249 1250 TAILQ_REMOVE(&dadq, (struct dadq *)dp, dad_list); 1251 free(dp, M_IP6NDP); 1252 dp = NULL; 1253 IFAFREE(ifa); 1254 goto done; 1255 } 1256 1257 /* Need more checks? */ 1258 if (dp->dad_ns_ocount < dp->dad_count) { 1259 /* 1260 * We have more NS to go. Send NS packet for DAD. 1261 */ 1262 nd6_dad_ns_output(dp, ifa); 1263 nd6_dad_starttimer(dp, 1264 (long)ND_IFINFO(ifa->ifa_ifp)->retrans * hz / 1000); 1265 } else { 1266 /* 1267 * We have transmitted sufficient number of DAD packets. 1268 * See what we've got. 1269 */ 1270 int duplicate; 1271 1272 duplicate = 0; 1273 1274 if (dp->dad_na_icount) { 1275 /* 1276 * the check is in nd6_dad_na_input(), 1277 * but just in case 1278 */ 1279 duplicate++; 1280 } 1281 1282 if (dp->dad_ns_icount) { 1283 /* We've seen NS, means DAD has failed. */ 1284 duplicate++; 1285 } 1286 1287 if (duplicate) { 1288 /* (*dp) will be freed in nd6_dad_duplicated() */ 1289 dp = NULL; 1290 nd6_dad_duplicated(ifa); 1291 } else { 1292 /* 1293 * We are done with DAD. No NA came, no NS came. 1294 * No duplicate address found. 1295 */ 1296 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1297 1298 nd6log((LOG_DEBUG, 1299 "%s: DAD complete for %s - no duplicates found\n", 1300 if_name(ifa->ifa_ifp), 1301 ip6_sprintf(&ia->ia_addr.sin6_addr))); 1302 1303 TAILQ_REMOVE(&dadq, (struct dadq *)dp, dad_list); 1304 free(dp, M_IP6NDP); 1305 dp = NULL; 1306 IFAFREE(ifa); 1307 } 1308 } 1309 1310 done: 1311 splx(s); 1312 } 1313 1314 void 1315 nd6_dad_duplicated(ifa) 1316 struct ifaddr *ifa; 1317 { 1318 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1319 struct ifnet *ifp; 1320 struct dadq *dp; 1321 1322 dp = nd6_dad_find(ifa); 1323 if (dp == NULL) { 1324 log(LOG_ERR, "nd6_dad_duplicated: DAD structure not found\n"); 1325 return; 1326 } 1327 1328 ifp = ifa->ifa_ifp; 1329 log(LOG_ERR, "%s: DAD detected duplicate IPv6 address %s: " 1330 "NS in/out=%d/%d, NA in=%d\n", 1331 if_name(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(ifp), ip6_sprintf(&ia->ia_addr.sin6_addr)); 1342 log(LOG_ERR, "%s: manual intervention required\n", 1343 if_name(ifp)); 1344 1345 /* 1346 * If the address is a link-local address formed from an interface 1347 * identifier based on the hardware address which is supposed to be 1348 * uniquely assigned (e.g., EUI-64 for an Ethernet interface), IP 1349 * operation on the interface SHOULD be disabled. 1350 * [rfc2462bis-03 Section 5.4.5] 1351 */ 1352 if (IN6_IS_ADDR_LINKLOCAL(&ia->ia_addr.sin6_addr)) { 1353 struct in6_addr in6; 1354 1355 /* 1356 * To avoid over-reaction, we only apply this logic when we are 1357 * very sure that hardware addresses are supposed to be unique. 1358 */ 1359 switch (ifp->if_type) { 1360 case IFT_ETHER: 1361 case IFT_FDDI: 1362 case IFT_ATM: 1363 case IFT_IEEE1394: 1364 #ifdef IFT_IEEE80211 1365 case IFT_IEEE80211: 1366 #endif 1367 in6 = ia->ia_addr.sin6_addr; 1368 if (in6_get_hw_ifid(ifp, &in6) == 0 && 1369 IN6_ARE_ADDR_EQUAL(&ia->ia_addr.sin6_addr, &in6)) { 1370 ND_IFINFO(ifp)->flags |= ND6_IFF_IFDISABLED; 1371 log(LOG_ERR, "%s: possible hardware address " 1372 "duplication detected, disable IPv6\n", 1373 if_name(ifp)); 1374 } 1375 break; 1376 } 1377 } 1378 1379 TAILQ_REMOVE(&dadq, (struct dadq *)dp, dad_list); 1380 free(dp, M_IP6NDP); 1381 dp = NULL; 1382 IFAFREE(ifa); 1383 } 1384 1385 static void 1386 nd6_dad_ns_output(dp, ifa) 1387 struct dadq *dp; 1388 struct ifaddr *ifa; 1389 { 1390 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1391 struct ifnet *ifp = ifa->ifa_ifp; 1392 1393 dp->dad_ns_tcount++; 1394 if ((ifp->if_flags & IFF_UP) == 0) { 1395 #if 0 1396 printf("%s: interface down?\n", if_name(ifp)); 1397 #endif 1398 return; 1399 } 1400 if ((ifp->if_flags & IFF_RUNNING) == 0) { 1401 #if 0 1402 printf("%s: interface not running?\n", if_name(ifp)); 1403 #endif 1404 return; 1405 } 1406 1407 dp->dad_ns_tcount = 0; 1408 dp->dad_ns_ocount++; 1409 nd6_ns_output(ifp, NULL, &ia->ia_addr.sin6_addr, NULL, 1); 1410 } 1411 1412 static void 1413 nd6_dad_ns_input(ifa) 1414 struct ifaddr *ifa; 1415 { 1416 struct in6_ifaddr *ia; 1417 const struct in6_addr *taddr6; 1418 struct dadq *dp; 1419 int duplicate; 1420 1421 if (ifa == NULL) 1422 panic("ifa == NULL in nd6_dad_ns_input"); 1423 1424 ia = (struct in6_ifaddr *)ifa; 1425 taddr6 = &ia->ia_addr.sin6_addr; 1426 duplicate = 0; 1427 dp = nd6_dad_find(ifa); 1428 1429 /* Quickhack - completely ignore DAD NS packets */ 1430 if (dad_ignore_ns) { 1431 nd6log((LOG_INFO, 1432 "nd6_dad_ns_input: ignoring DAD NS packet for " 1433 "address %s(%s)\n", ip6_sprintf(taddr6), 1434 if_name(ifa->ifa_ifp))); 1435 return; 1436 } 1437 1438 /* 1439 * if I'm yet to start DAD, someone else started using this address 1440 * first. I have a duplicate and you win. 1441 */ 1442 if (dp == NULL || dp->dad_ns_ocount == 0) 1443 duplicate++; 1444 1445 /* XXX more checks for loopback situation - see nd6_dad_timer too */ 1446 1447 if (duplicate) { 1448 dp = NULL; /* will be freed in nd6_dad_duplicated() */ 1449 nd6_dad_duplicated(ifa); 1450 } else { 1451 /* 1452 * not sure if I got a duplicate. 1453 * increment ns count and see what happens. 1454 */ 1455 if (dp) 1456 dp->dad_ns_icount++; 1457 } 1458 } 1459 1460 static void 1461 nd6_dad_na_input(ifa) 1462 struct ifaddr *ifa; 1463 { 1464 struct dadq *dp; 1465 1466 if (ifa == NULL) 1467 panic("ifa == NULL in nd6_dad_na_input"); 1468 1469 dp = nd6_dad_find(ifa); 1470 if (dp) 1471 dp->dad_na_icount++; 1472 1473 /* remove the address. */ 1474 nd6_dad_duplicated(ifa); 1475 }
Cache object: e0ebfdf73d8d791cc04b347a5cec5057
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