1 /*- 2 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project. 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. Neither the name of the project nor the names of its contributors 14 * may be used to endorse or promote products derived from this software 15 * without specific prior written permission. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE 21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * SUCH DAMAGE. 28 * 29 * $KAME: nd6_nbr.c,v 1.86 2002/01/21 02:33:04 jinmei Exp $ 30 */ 31 32 #include <sys/cdefs.h> 33 __FBSDID("$FreeBSD$"); 34 35 #include "opt_inet.h" 36 #include "opt_inet6.h" 37 #include "opt_ipsec.h" 38 #include "opt_mpath.h" 39 40 #include <sys/param.h> 41 #include <sys/systm.h> 42 #include <sys/malloc.h> 43 #include <sys/lock.h> 44 #include <sys/rwlock.h> 45 #include <sys/mbuf.h> 46 #include <sys/socket.h> 47 #include <sys/sockio.h> 48 #include <sys/time.h> 49 #include <sys/kernel.h> 50 #include <sys/errno.h> 51 #include <sys/syslog.h> 52 #include <sys/queue.h> 53 #include <sys/callout.h> 54 55 #include <net/if.h> 56 #include <net/if_types.h> 57 #include <net/if_dl.h> 58 #include <net/if_var.h> 59 #include <net/route.h> 60 #ifdef RADIX_MPATH 61 #include <net/radix_mpath.h> 62 #endif 63 64 #include <netinet/in.h> 65 #include <netinet/in_var.h> 66 #include <net/if_llatbl.h> 67 #define L3_ADDR_SIN6(le) ((struct sockaddr_in6 *) L3_ADDR(le)) 68 #include <netinet6/in6_var.h> 69 #include <netinet6/in6_ifattach.h> 70 #include <netinet/ip6.h> 71 #include <netinet6/ip6_var.h> 72 #include <netinet6/scope6_var.h> 73 #include <netinet6/nd6.h> 74 #include <netinet/icmp6.h> 75 #include <netinet/ip_carp.h> 76 #include <netinet6/send.h> 77 78 #define SDL(s) ((struct sockaddr_dl *)s) 79 80 struct dadq; 81 static struct dadq *nd6_dad_find(struct ifaddr *); 82 static void nd6_dad_starttimer(struct dadq *, int); 83 static void nd6_dad_stoptimer(struct dadq *); 84 static void nd6_dad_timer(struct dadq *); 85 static void nd6_dad_ns_output(struct dadq *, struct ifaddr *); 86 static void nd6_dad_ns_input(struct ifaddr *); 87 static void nd6_dad_na_input(struct ifaddr *); 88 89 VNET_DEFINE(int, dad_ignore_ns) = 0; /* ignore NS in DAD - specwise incorrect*/ 90 VNET_DEFINE(int, dad_maxtry) = 15; /* max # of *tries* to transmit DAD packet */ 91 #define V_dad_ignore_ns VNET(dad_ignore_ns) 92 #define V_dad_maxtry VNET(dad_maxtry) 93 94 /* 95 * Input a Neighbor Solicitation Message. 96 * 97 * Based on RFC 2461 98 * Based on RFC 2462 (duplicate address detection) 99 */ 100 void 101 nd6_ns_input(struct mbuf *m, int off, int icmp6len) 102 { 103 struct ifnet *ifp = m->m_pkthdr.rcvif; 104 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 105 struct nd_neighbor_solicit *nd_ns; 106 struct in6_addr saddr6 = ip6->ip6_src; 107 struct in6_addr daddr6 = ip6->ip6_dst; 108 struct in6_addr taddr6; 109 struct in6_addr myaddr6; 110 char *lladdr = NULL; 111 struct ifaddr *ifa = NULL; 112 int lladdrlen = 0; 113 int anycast = 0, proxy = 0, tentative = 0; 114 int tlladdr; 115 union nd_opts ndopts; 116 struct sockaddr_dl proxydl; 117 char ip6bufs[INET6_ADDRSTRLEN], ip6bufd[INET6_ADDRSTRLEN]; 118 119 #ifndef PULLDOWN_TEST 120 IP6_EXTHDR_CHECK(m, off, icmp6len,); 121 nd_ns = (struct nd_neighbor_solicit *)((caddr_t)ip6 + off); 122 #else 123 IP6_EXTHDR_GET(nd_ns, struct nd_neighbor_solicit *, m, off, icmp6len); 124 if (nd_ns == NULL) { 125 ICMP6STAT_INC(icp6s_tooshort); 126 return; 127 } 128 #endif 129 ip6 = mtod(m, struct ip6_hdr *); /* adjust pointer for safety */ 130 taddr6 = nd_ns->nd_ns_target; 131 if (in6_setscope(&taddr6, ifp, NULL) != 0) 132 goto bad; 133 134 if (ip6->ip6_hlim != 255) { 135 nd6log((LOG_ERR, 136 "nd6_ns_input: invalid hlim (%d) from %s to %s on %s\n", 137 ip6->ip6_hlim, ip6_sprintf(ip6bufs, &ip6->ip6_src), 138 ip6_sprintf(ip6bufd, &ip6->ip6_dst), if_name(ifp))); 139 goto bad; 140 } 141 142 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) { 143 /* dst has to be a solicited node multicast address. */ 144 if (daddr6.s6_addr16[0] == IPV6_ADDR_INT16_MLL && 145 /* don't check ifindex portion */ 146 daddr6.s6_addr32[1] == 0 && 147 daddr6.s6_addr32[2] == IPV6_ADDR_INT32_ONE && 148 daddr6.s6_addr8[12] == 0xff) { 149 ; /* good */ 150 } else { 151 nd6log((LOG_INFO, "nd6_ns_input: bad DAD packet " 152 "(wrong ip6 dst)\n")); 153 goto bad; 154 } 155 } else if (!V_nd6_onlink_ns_rfc4861) { 156 struct sockaddr_in6 src_sa6; 157 158 /* 159 * According to recent IETF discussions, it is not a good idea 160 * to accept a NS from an address which would not be deemed 161 * to be a neighbor otherwise. This point is expected to be 162 * clarified in future revisions of the specification. 163 */ 164 bzero(&src_sa6, sizeof(src_sa6)); 165 src_sa6.sin6_family = AF_INET6; 166 src_sa6.sin6_len = sizeof(src_sa6); 167 src_sa6.sin6_addr = saddr6; 168 if (nd6_is_addr_neighbor(&src_sa6, ifp) == 0) { 169 nd6log((LOG_INFO, "nd6_ns_input: " 170 "NS packet from non-neighbor\n")); 171 goto bad; 172 } 173 } 174 175 if (IN6_IS_ADDR_MULTICAST(&taddr6)) { 176 nd6log((LOG_INFO, "nd6_ns_input: bad NS target (multicast)\n")); 177 goto bad; 178 } 179 180 icmp6len -= sizeof(*nd_ns); 181 nd6_option_init(nd_ns + 1, icmp6len, &ndopts); 182 if (nd6_options(&ndopts) < 0) { 183 nd6log((LOG_INFO, 184 "nd6_ns_input: invalid ND option, ignored\n")); 185 /* nd6_options have incremented stats */ 186 goto freeit; 187 } 188 189 if (ndopts.nd_opts_src_lladdr) { 190 lladdr = (char *)(ndopts.nd_opts_src_lladdr + 1); 191 lladdrlen = ndopts.nd_opts_src_lladdr->nd_opt_len << 3; 192 } 193 194 if (IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_src) && lladdr) { 195 nd6log((LOG_INFO, "nd6_ns_input: bad DAD packet " 196 "(link-layer address option)\n")); 197 goto bad; 198 } 199 200 /* 201 * Attaching target link-layer address to the NA? 202 * (RFC 2461 7.2.4) 203 * 204 * NS IP dst is unicast/anycast MUST NOT add 205 * NS IP dst is solicited-node multicast MUST add 206 * 207 * In implementation, we add target link-layer address by default. 208 * We do not add one in MUST NOT cases. 209 */ 210 if (!IN6_IS_ADDR_MULTICAST(&daddr6)) 211 tlladdr = 0; 212 else 213 tlladdr = 1; 214 215 /* 216 * Target address (taddr6) must be either: 217 * (1) Valid unicast/anycast address for my receiving interface, 218 * (2) Unicast address for which I'm offering proxy service, or 219 * (3) "tentative" address on which DAD is being performed. 220 */ 221 /* (1) and (3) check. */ 222 if (ifp->if_carp) 223 ifa = (*carp_iamatch6_p)(ifp, &taddr6); 224 if (ifa == NULL) 225 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &taddr6); 226 227 /* (2) check. */ 228 if (ifa == NULL) { 229 struct rtentry *rt; 230 struct sockaddr_in6 tsin6; 231 int need_proxy; 232 #ifdef RADIX_MPATH 233 struct route_in6 ro; 234 #endif 235 236 bzero(&tsin6, sizeof tsin6); 237 tsin6.sin6_len = sizeof(struct sockaddr_in6); 238 tsin6.sin6_family = AF_INET6; 239 tsin6.sin6_addr = taddr6; 240 241 #ifdef RADIX_MPATH 242 bzero(&ro, sizeof(ro)); 243 ro.ro_dst = tsin6; 244 rtalloc_mpath((struct route *)&ro, RTF_ANNOUNCE); 245 rt = ro.ro_rt; 246 #else 247 rt = rtalloc1((struct sockaddr *)&tsin6, 0, 0); 248 #endif 249 need_proxy = (rt && (rt->rt_flags & RTF_ANNOUNCE) != 0 && 250 rt->rt_gateway->sa_family == AF_LINK); 251 if (rt != NULL) { 252 /* 253 * Make a copy while we can be sure that rt_gateway 254 * is still stable before unlocking to avoid lock 255 * order problems. proxydl will only be used if 256 * proxy will be set in the next block. 257 */ 258 if (need_proxy) 259 proxydl = *SDL(rt->rt_gateway); 260 RTFREE_LOCKED(rt); 261 } 262 if (need_proxy) { 263 /* 264 * proxy NDP for single entry 265 */ 266 ifa = (struct ifaddr *)in6ifa_ifpforlinklocal(ifp, 267 IN6_IFF_NOTREADY|IN6_IFF_ANYCAST); 268 if (ifa) 269 proxy = 1; 270 } 271 } 272 if (ifa == NULL) { 273 /* 274 * We've got an NS packet, and we don't have that adddress 275 * assigned for us. We MUST silently ignore it. 276 * See RFC2461 7.2.3. 277 */ 278 goto freeit; 279 } 280 myaddr6 = *IFA_IN6(ifa); 281 anycast = ((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_ANYCAST; 282 tentative = ((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_TENTATIVE; 283 if (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_DUPLICATED) 284 goto freeit; 285 286 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) { 287 nd6log((LOG_INFO, "nd6_ns_input: lladdrlen mismatch for %s " 288 "(if %d, NS packet %d)\n", 289 ip6_sprintf(ip6bufs, &taddr6), 290 ifp->if_addrlen, lladdrlen - 2)); 291 goto bad; 292 } 293 294 if (IN6_ARE_ADDR_EQUAL(&myaddr6, &saddr6)) { 295 nd6log((LOG_INFO, "nd6_ns_input: duplicate IP6 address %s\n", 296 ip6_sprintf(ip6bufs, &saddr6))); 297 goto freeit; 298 } 299 300 /* 301 * We have neighbor solicitation packet, with target address equals to 302 * one of my tentative address. 303 * 304 * src addr how to process? 305 * --- --- 306 * multicast of course, invalid (rejected in ip6_input) 307 * unicast somebody is doing address resolution -> ignore 308 * unspec dup address detection 309 * 310 * The processing is defined in RFC 2462. 311 */ 312 if (tentative) { 313 /* 314 * If source address is unspecified address, it is for 315 * duplicate address detection. 316 * 317 * If not, the packet is for addess resolution; 318 * silently ignore it. 319 */ 320 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) 321 nd6_dad_ns_input(ifa); 322 323 goto freeit; 324 } 325 326 /* 327 * If the source address is unspecified address, entries must not 328 * be created or updated. 329 * It looks that sender is performing DAD. Output NA toward 330 * all-node multicast address, to tell the sender that I'm using 331 * the address. 332 * S bit ("solicited") must be zero. 333 */ 334 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) { 335 struct in6_addr in6_all; 336 337 in6_all = in6addr_linklocal_allnodes; 338 if (in6_setscope(&in6_all, ifp, NULL) != 0) 339 goto bad; 340 nd6_na_output(ifp, &in6_all, &taddr6, 341 ((anycast || proxy || !tlladdr) ? 0 : ND_NA_FLAG_OVERRIDE) | 342 (V_ip6_forwarding ? ND_NA_FLAG_ROUTER : 0), 343 tlladdr, proxy ? (struct sockaddr *)&proxydl : NULL); 344 goto freeit; 345 } 346 347 nd6_cache_lladdr(ifp, &saddr6, lladdr, lladdrlen, 348 ND_NEIGHBOR_SOLICIT, 0); 349 350 nd6_na_output(ifp, &saddr6, &taddr6, 351 ((anycast || proxy || !tlladdr) ? 0 : ND_NA_FLAG_OVERRIDE) | 352 (V_ip6_forwarding ? ND_NA_FLAG_ROUTER : 0) | ND_NA_FLAG_SOLICITED, 353 tlladdr, proxy ? (struct sockaddr *)&proxydl : NULL); 354 freeit: 355 if (ifa != NULL) 356 ifa_free(ifa); 357 m_freem(m); 358 return; 359 360 bad: 361 nd6log((LOG_ERR, "nd6_ns_input: src=%s\n", 362 ip6_sprintf(ip6bufs, &saddr6))); 363 nd6log((LOG_ERR, "nd6_ns_input: dst=%s\n", 364 ip6_sprintf(ip6bufs, &daddr6))); 365 nd6log((LOG_ERR, "nd6_ns_input: tgt=%s\n", 366 ip6_sprintf(ip6bufs, &taddr6))); 367 ICMP6STAT_INC(icp6s_badns); 368 if (ifa != NULL) 369 ifa_free(ifa); 370 m_freem(m); 371 } 372 373 /* 374 * Output a Neighbor Solicitation Message. Caller specifies: 375 * - ICMP6 header source IP6 address 376 * - ND6 header target IP6 address 377 * - ND6 header source datalink address 378 * 379 * Based on RFC 2461 380 * Based on RFC 2462 (duplicate address detection) 381 * 382 * ln - for source address determination 383 * dad - duplicate address detection 384 */ 385 void 386 nd6_ns_output(struct ifnet *ifp, const struct in6_addr *daddr6, 387 const struct in6_addr *taddr6, struct llentry *ln, int dad) 388 { 389 struct mbuf *m; 390 struct m_tag *mtag; 391 struct ip6_hdr *ip6; 392 struct nd_neighbor_solicit *nd_ns; 393 struct ip6_moptions im6o; 394 int icmp6len; 395 int maxlen; 396 caddr_t mac; 397 struct route_in6 ro; 398 399 if (IN6_IS_ADDR_MULTICAST(taddr6)) 400 return; 401 402 /* estimate the size of message */ 403 maxlen = sizeof(*ip6) + sizeof(*nd_ns); 404 maxlen += (sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7; 405 if (max_linkhdr + maxlen >= MCLBYTES) { 406 #ifdef DIAGNOSTIC 407 printf("nd6_ns_output: max_linkhdr + maxlen >= MCLBYTES " 408 "(%d + %d > %d)\n", max_linkhdr, maxlen, MCLBYTES); 409 #endif 410 return; 411 } 412 413 MGETHDR(m, M_DONTWAIT, MT_DATA); 414 if (m && max_linkhdr + maxlen >= MHLEN) { 415 MCLGET(m, M_DONTWAIT); 416 if ((m->m_flags & M_EXT) == 0) { 417 m_free(m); 418 m = NULL; 419 } 420 } 421 if (m == NULL) 422 return; 423 m->m_pkthdr.rcvif = NULL; 424 425 bzero(&ro, sizeof(ro)); 426 427 if (daddr6 == NULL || IN6_IS_ADDR_MULTICAST(daddr6)) { 428 m->m_flags |= M_MCAST; 429 im6o.im6o_multicast_ifp = ifp; 430 im6o.im6o_multicast_hlim = 255; 431 im6o.im6o_multicast_loop = 0; 432 } 433 434 icmp6len = sizeof(*nd_ns); 435 m->m_pkthdr.len = m->m_len = sizeof(*ip6) + icmp6len; 436 m->m_data += max_linkhdr; /* or MH_ALIGN() equivalent? */ 437 438 /* fill neighbor solicitation packet */ 439 ip6 = mtod(m, struct ip6_hdr *); 440 ip6->ip6_flow = 0; 441 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 442 ip6->ip6_vfc |= IPV6_VERSION; 443 /* ip6->ip6_plen will be set later */ 444 ip6->ip6_nxt = IPPROTO_ICMPV6; 445 ip6->ip6_hlim = 255; 446 if (daddr6) 447 ip6->ip6_dst = *daddr6; 448 else { 449 ip6->ip6_dst.s6_addr16[0] = IPV6_ADDR_INT16_MLL; 450 ip6->ip6_dst.s6_addr16[1] = 0; 451 ip6->ip6_dst.s6_addr32[1] = 0; 452 ip6->ip6_dst.s6_addr32[2] = IPV6_ADDR_INT32_ONE; 453 ip6->ip6_dst.s6_addr32[3] = taddr6->s6_addr32[3]; 454 ip6->ip6_dst.s6_addr8[12] = 0xff; 455 if (in6_setscope(&ip6->ip6_dst, ifp, NULL) != 0) 456 goto bad; 457 } 458 if (!dad) { 459 struct ifaddr *ifa; 460 461 /* 462 * RFC2461 7.2.2: 463 * "If the source address of the packet prompting the 464 * solicitation is the same as one of the addresses assigned 465 * to the outgoing interface, that address SHOULD be placed 466 * in the IP Source Address of the outgoing solicitation. 467 * Otherwise, any one of the addresses assigned to the 468 * interface should be used." 469 * 470 * We use the source address for the prompting packet 471 * (saddr6), if: 472 * - saddr6 is given from the caller (by giving "ln"), and 473 * - saddr6 belongs to the outgoing interface. 474 * Otherwise, we perform the source address selection as usual. 475 */ 476 struct in6_addr *hsrc; 477 478 hsrc = NULL; 479 if (ln != NULL) { 480 LLE_RLOCK(ln); 481 if (ln->la_hold != NULL) { 482 struct ip6_hdr *hip6; /* hold ip6 */ 483 484 /* 485 * assuming every packet in la_hold has the same IP 486 * header 487 */ 488 hip6 = mtod(ln->la_hold, struct ip6_hdr *); 489 /* XXX pullup? */ 490 if (sizeof(*hip6) < ln->la_hold->m_len) { 491 ip6->ip6_src = hip6->ip6_src; 492 hsrc = &hip6->ip6_src; 493 } 494 } 495 LLE_RUNLOCK(ln); 496 } 497 if (hsrc && (ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, 498 hsrc)) != NULL) { 499 /* ip6_src set already. */ 500 ifa_free(ifa); 501 } else { 502 int error; 503 struct sockaddr_in6 dst_sa; 504 struct in6_addr src_in; 505 506 bzero(&dst_sa, sizeof(dst_sa)); 507 dst_sa.sin6_family = AF_INET6; 508 dst_sa.sin6_len = sizeof(dst_sa); 509 dst_sa.sin6_addr = ip6->ip6_dst; 510 511 error = in6_selectsrc(&dst_sa, NULL, 512 NULL, &ro, NULL, NULL, &src_in); 513 if (error) { 514 char ip6buf[INET6_ADDRSTRLEN]; 515 nd6log((LOG_DEBUG, 516 "nd6_ns_output: source can't be " 517 "determined: dst=%s, error=%d\n", 518 ip6_sprintf(ip6buf, &dst_sa.sin6_addr), 519 error)); 520 goto bad; 521 } 522 ip6->ip6_src = src_in; 523 } 524 } else { 525 /* 526 * Source address for DAD packet must always be IPv6 527 * unspecified address. (0::0) 528 * We actually don't have to 0-clear the address (we did it 529 * above), but we do so here explicitly to make the intention 530 * clearer. 531 */ 532 bzero(&ip6->ip6_src, sizeof(ip6->ip6_src)); 533 } 534 nd_ns = (struct nd_neighbor_solicit *)(ip6 + 1); 535 nd_ns->nd_ns_type = ND_NEIGHBOR_SOLICIT; 536 nd_ns->nd_ns_code = 0; 537 nd_ns->nd_ns_reserved = 0; 538 nd_ns->nd_ns_target = *taddr6; 539 in6_clearscope(&nd_ns->nd_ns_target); /* XXX */ 540 541 /* 542 * Add source link-layer address option. 543 * 544 * spec implementation 545 * --- --- 546 * DAD packet MUST NOT do not add the option 547 * there's no link layer address: 548 * impossible do not add the option 549 * there's link layer address: 550 * Multicast NS MUST add one add the option 551 * Unicast NS SHOULD add one add the option 552 */ 553 if (!dad && (mac = nd6_ifptomac(ifp))) { 554 int optlen = sizeof(struct nd_opt_hdr) + ifp->if_addrlen; 555 struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)(nd_ns + 1); 556 /* 8 byte alignments... */ 557 optlen = (optlen + 7) & ~7; 558 559 m->m_pkthdr.len += optlen; 560 m->m_len += optlen; 561 icmp6len += optlen; 562 bzero((caddr_t)nd_opt, optlen); 563 nd_opt->nd_opt_type = ND_OPT_SOURCE_LINKADDR; 564 nd_opt->nd_opt_len = optlen >> 3; 565 bcopy(mac, (caddr_t)(nd_opt + 1), ifp->if_addrlen); 566 } 567 568 ip6->ip6_plen = htons((u_short)icmp6len); 569 nd_ns->nd_ns_cksum = 0; 570 nd_ns->nd_ns_cksum = 571 in6_cksum(m, IPPROTO_ICMPV6, sizeof(*ip6), icmp6len); 572 573 if (send_sendso_input_hook != NULL) { 574 mtag = m_tag_get(PACKET_TAG_ND_OUTGOING, 575 sizeof(unsigned short), M_NOWAIT); 576 if (mtag == NULL) 577 goto bad; 578 *(unsigned short *)(mtag + 1) = nd_ns->nd_ns_type; 579 m_tag_prepend(m, mtag); 580 } 581 582 ip6_output(m, NULL, &ro, dad ? IPV6_UNSPECSRC : 0, &im6o, NULL, NULL); 583 icmp6_ifstat_inc(ifp, ifs6_out_msg); 584 icmp6_ifstat_inc(ifp, ifs6_out_neighborsolicit); 585 ICMP6STAT_INC(icp6s_outhist[ND_NEIGHBOR_SOLICIT]); 586 587 if (ro.ro_rt) { /* we don't cache this route. */ 588 RTFREE(ro.ro_rt); 589 } 590 return; 591 592 bad: 593 if (ro.ro_rt) { 594 RTFREE(ro.ro_rt); 595 } 596 m_freem(m); 597 return; 598 } 599 600 /* 601 * Neighbor advertisement input handling. 602 * 603 * Based on RFC 2461 604 * Based on RFC 2462 (duplicate address detection) 605 * 606 * the following items are not implemented yet: 607 * - proxy advertisement delay rule (RFC2461 7.2.8, last paragraph, SHOULD) 608 * - anycast advertisement delay rule (RFC2461 7.2.7, SHOULD) 609 */ 610 void 611 nd6_na_input(struct mbuf *m, int off, int icmp6len) 612 { 613 struct ifnet *ifp = m->m_pkthdr.rcvif; 614 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 615 struct nd_neighbor_advert *nd_na; 616 struct in6_addr daddr6 = ip6->ip6_dst; 617 struct in6_addr taddr6; 618 int flags; 619 int is_router; 620 int is_solicited; 621 int is_override; 622 char *lladdr = NULL; 623 int lladdrlen = 0; 624 int checklink = 0; 625 struct ifaddr *ifa; 626 struct llentry *ln = NULL; 627 union nd_opts ndopts; 628 struct mbuf *chain = NULL; 629 struct m_tag *mtag; 630 struct sockaddr_in6 sin6; 631 char ip6bufs[INET6_ADDRSTRLEN], ip6bufd[INET6_ADDRSTRLEN]; 632 633 if (ip6->ip6_hlim != 255) { 634 nd6log((LOG_ERR, 635 "nd6_na_input: invalid hlim (%d) from %s to %s on %s\n", 636 ip6->ip6_hlim, ip6_sprintf(ip6bufs, &ip6->ip6_src), 637 ip6_sprintf(ip6bufd, &ip6->ip6_dst), if_name(ifp))); 638 goto bad; 639 } 640 641 #ifndef PULLDOWN_TEST 642 IP6_EXTHDR_CHECK(m, off, icmp6len,); 643 nd_na = (struct nd_neighbor_advert *)((caddr_t)ip6 + off); 644 #else 645 IP6_EXTHDR_GET(nd_na, struct nd_neighbor_advert *, m, off, icmp6len); 646 if (nd_na == NULL) { 647 ICMP6STAT_INC(icp6s_tooshort); 648 return; 649 } 650 #endif 651 652 flags = nd_na->nd_na_flags_reserved; 653 is_router = ((flags & ND_NA_FLAG_ROUTER) != 0); 654 is_solicited = ((flags & ND_NA_FLAG_SOLICITED) != 0); 655 is_override = ((flags & ND_NA_FLAG_OVERRIDE) != 0); 656 657 taddr6 = nd_na->nd_na_target; 658 if (in6_setscope(&taddr6, ifp, NULL)) 659 goto bad; /* XXX: impossible */ 660 661 if (IN6_IS_ADDR_MULTICAST(&taddr6)) { 662 nd6log((LOG_ERR, 663 "nd6_na_input: invalid target address %s\n", 664 ip6_sprintf(ip6bufs, &taddr6))); 665 goto bad; 666 } 667 if (IN6_IS_ADDR_MULTICAST(&daddr6)) 668 if (is_solicited) { 669 nd6log((LOG_ERR, 670 "nd6_na_input: a solicited adv is multicasted\n")); 671 goto bad; 672 } 673 674 icmp6len -= sizeof(*nd_na); 675 nd6_option_init(nd_na + 1, icmp6len, &ndopts); 676 if (nd6_options(&ndopts) < 0) { 677 nd6log((LOG_INFO, 678 "nd6_na_input: invalid ND option, ignored\n")); 679 /* nd6_options have incremented stats */ 680 goto freeit; 681 } 682 683 if (ndopts.nd_opts_tgt_lladdr) { 684 lladdr = (char *)(ndopts.nd_opts_tgt_lladdr + 1); 685 lladdrlen = ndopts.nd_opts_tgt_lladdr->nd_opt_len << 3; 686 } 687 688 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &taddr6); 689 690 /* 691 * Target address matches one of my interface address. 692 * 693 * If my address is tentative, this means that there's somebody 694 * already using the same address as mine. This indicates DAD failure. 695 * This is defined in RFC 2462. 696 * 697 * Otherwise, process as defined in RFC 2461. 698 */ 699 if (ifa 700 && (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_TENTATIVE)) { 701 ifa_free(ifa); 702 nd6_dad_na_input(ifa); 703 goto freeit; 704 } 705 706 /* Just for safety, maybe unnecessary. */ 707 if (ifa) { 708 ifa_free(ifa); 709 log(LOG_ERR, 710 "nd6_na_input: duplicate IP6 address %s\n", 711 ip6_sprintf(ip6bufs, &taddr6)); 712 goto freeit; 713 } 714 715 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) { 716 nd6log((LOG_INFO, "nd6_na_input: lladdrlen mismatch for %s " 717 "(if %d, NA packet %d)\n", ip6_sprintf(ip6bufs, &taddr6), 718 ifp->if_addrlen, lladdrlen - 2)); 719 goto bad; 720 } 721 722 /* 723 * If no neighbor cache entry is found, NA SHOULD silently be 724 * discarded. 725 */ 726 IF_AFDATA_LOCK(ifp); 727 ln = nd6_lookup(&taddr6, LLE_EXCLUSIVE, ifp); 728 IF_AFDATA_UNLOCK(ifp); 729 if (ln == NULL) { 730 goto freeit; 731 } 732 733 if (ln->ln_state == ND6_LLINFO_INCOMPLETE) { 734 /* 735 * If the link-layer has address, and no lladdr option came, 736 * discard the packet. 737 */ 738 if (ifp->if_addrlen && lladdr == NULL) { 739 goto freeit; 740 } 741 742 /* 743 * Record link-layer address, and update the state. 744 */ 745 bcopy(lladdr, &ln->ll_addr, ifp->if_addrlen); 746 ln->la_flags |= LLE_VALID; 747 if (is_solicited) { 748 ln->ln_state = ND6_LLINFO_REACHABLE; 749 ln->ln_byhint = 0; 750 if (!ND6_LLINFO_PERMANENT(ln)) { 751 nd6_llinfo_settimer_locked(ln, 752 (long)ND_IFINFO(ln->lle_tbl->llt_ifp)->reachable * hz); 753 } 754 } else { 755 ln->ln_state = ND6_LLINFO_STALE; 756 nd6_llinfo_settimer_locked(ln, (long)V_nd6_gctimer * hz); 757 } 758 if ((ln->ln_router = is_router) != 0) { 759 /* 760 * This means a router's state has changed from 761 * non-reachable to probably reachable, and might 762 * affect the status of associated prefixes.. 763 */ 764 checklink = 1; 765 } 766 } else { 767 int llchange; 768 769 /* 770 * Check if the link-layer address has changed or not. 771 */ 772 if (lladdr == NULL) 773 llchange = 0; 774 else { 775 if (ln->la_flags & LLE_VALID) { 776 if (bcmp(lladdr, &ln->ll_addr, ifp->if_addrlen)) 777 llchange = 1; 778 else 779 llchange = 0; 780 } else 781 llchange = 1; 782 } 783 784 /* 785 * This is VERY complex. Look at it with care. 786 * 787 * override solicit lladdr llchange action 788 * (L: record lladdr) 789 * 790 * 0 0 n -- (2c) 791 * 0 0 y n (2b) L 792 * 0 0 y y (1) REACHABLE->STALE 793 * 0 1 n -- (2c) *->REACHABLE 794 * 0 1 y n (2b) L *->REACHABLE 795 * 0 1 y y (1) REACHABLE->STALE 796 * 1 0 n -- (2a) 797 * 1 0 y n (2a) L 798 * 1 0 y y (2a) L *->STALE 799 * 1 1 n -- (2a) *->REACHABLE 800 * 1 1 y n (2a) L *->REACHABLE 801 * 1 1 y y (2a) L *->REACHABLE 802 */ 803 if (!is_override && (lladdr != NULL && llchange)) { /* (1) */ 804 /* 805 * If state is REACHABLE, make it STALE. 806 * no other updates should be done. 807 */ 808 if (ln->ln_state == ND6_LLINFO_REACHABLE) { 809 ln->ln_state = ND6_LLINFO_STALE; 810 nd6_llinfo_settimer_locked(ln, (long)V_nd6_gctimer * hz); 811 } 812 goto freeit; 813 } else if (is_override /* (2a) */ 814 || (!is_override && (lladdr != NULL && !llchange)) /* (2b) */ 815 || lladdr == NULL) { /* (2c) */ 816 /* 817 * Update link-local address, if any. 818 */ 819 if (lladdr != NULL) { 820 bcopy(lladdr, &ln->ll_addr, ifp->if_addrlen); 821 ln->la_flags |= LLE_VALID; 822 } 823 824 /* 825 * If solicited, make the state REACHABLE. 826 * If not solicited and the link-layer address was 827 * changed, make it STALE. 828 */ 829 if (is_solicited) { 830 ln->ln_state = ND6_LLINFO_REACHABLE; 831 ln->ln_byhint = 0; 832 if (!ND6_LLINFO_PERMANENT(ln)) { 833 nd6_llinfo_settimer_locked(ln, 834 (long)ND_IFINFO(ifp)->reachable * hz); 835 } 836 } else { 837 if (lladdr != NULL && llchange) { 838 ln->ln_state = ND6_LLINFO_STALE; 839 nd6_llinfo_settimer_locked(ln, 840 (long)V_nd6_gctimer * hz); 841 } 842 } 843 } 844 845 if (ln->ln_router && !is_router) { 846 /* 847 * The peer dropped the router flag. 848 * Remove the sender from the Default Router List and 849 * update the Destination Cache entries. 850 */ 851 struct nd_defrouter *dr; 852 struct in6_addr *in6; 853 854 in6 = &L3_ADDR_SIN6(ln)->sin6_addr; 855 856 /* 857 * Lock to protect the default router list. 858 * XXX: this might be unnecessary, since this function 859 * is only called under the network software interrupt 860 * context. However, we keep it just for safety. 861 */ 862 dr = defrouter_lookup(in6, ln->lle_tbl->llt_ifp); 863 if (dr) 864 defrtrlist_del(dr); 865 else if (!V_ip6_forwarding) { 866 /* 867 * Even if the neighbor is not in the default 868 * router list, the neighbor may be used 869 * as a next hop for some destinations 870 * (e.g. redirect case). So we must 871 * call rt6_flush explicitly. 872 */ 873 rt6_flush(&ip6->ip6_src, ifp); 874 } 875 } 876 ln->ln_router = is_router; 877 } 878 /* XXX - QL 879 * Does this matter? 880 * rt->rt_flags &= ~RTF_REJECT; 881 */ 882 ln->la_asked = 0; 883 if (ln->la_hold) { 884 struct mbuf *m_hold, *m_hold_next; 885 886 /* 887 * reset the la_hold in advance, to explicitly 888 * prevent a la_hold lookup in nd6_output() 889 * (wouldn't happen, though...) 890 */ 891 for (m_hold = ln->la_hold, ln->la_hold = NULL; 892 m_hold; m_hold = m_hold_next) { 893 m_hold_next = m_hold->m_nextpkt; 894 m_hold->m_nextpkt = NULL; 895 /* 896 * we assume ifp is not a loopback here, so just set 897 * the 2nd argument as the 1st one. 898 */ 899 900 if (send_sendso_input_hook != NULL) { 901 mtag = m_tag_get(PACKET_TAG_ND_OUTGOING, 902 sizeof(unsigned short), M_NOWAIT); 903 if (mtag == NULL) 904 goto bad; 905 m_tag_prepend(m, mtag); 906 } 907 908 nd6_output_lle(ifp, ifp, m_hold, L3_ADDR_SIN6(ln), NULL, ln, &chain); 909 } 910 } 911 freeit: 912 if (ln != NULL) { 913 if (chain) 914 memcpy(&sin6, L3_ADDR_SIN6(ln), sizeof(sin6)); 915 LLE_WUNLOCK(ln); 916 917 if (chain) 918 nd6_output_flush(ifp, ifp, chain, &sin6, NULL); 919 } 920 if (checklink) 921 pfxlist_onlink_check(); 922 923 m_freem(m); 924 return; 925 926 bad: 927 if (ln != NULL) 928 LLE_WUNLOCK(ln); 929 930 ICMP6STAT_INC(icp6s_badna); 931 m_freem(m); 932 } 933 934 /* 935 * Neighbor advertisement output handling. 936 * 937 * Based on RFC 2461 938 * 939 * the following items are not implemented yet: 940 * - proxy advertisement delay rule (RFC2461 7.2.8, last paragraph, SHOULD) 941 * - anycast advertisement delay rule (RFC2461 7.2.7, SHOULD) 942 * 943 * tlladdr - 1 if include target link-layer address 944 * sdl0 - sockaddr_dl (= proxy NA) or NULL 945 */ 946 void 947 nd6_na_output(struct ifnet *ifp, const struct in6_addr *daddr6_0, 948 const struct in6_addr *taddr6, u_long flags, int tlladdr, 949 struct sockaddr *sdl0) 950 { 951 struct mbuf *m; 952 struct m_tag *mtag; 953 struct ip6_hdr *ip6; 954 struct nd_neighbor_advert *nd_na; 955 struct ip6_moptions im6o; 956 struct in6_addr src, daddr6; 957 struct sockaddr_in6 dst_sa; 958 int icmp6len, maxlen, error; 959 caddr_t mac = NULL; 960 struct route_in6 ro; 961 962 bzero(&ro, sizeof(ro)); 963 964 daddr6 = *daddr6_0; /* make a local copy for modification */ 965 966 /* estimate the size of message */ 967 maxlen = sizeof(*ip6) + sizeof(*nd_na); 968 maxlen += (sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7; 969 if (max_linkhdr + maxlen >= MCLBYTES) { 970 #ifdef DIAGNOSTIC 971 printf("nd6_na_output: max_linkhdr + maxlen >= MCLBYTES " 972 "(%d + %d > %d)\n", max_linkhdr, maxlen, MCLBYTES); 973 #endif 974 return; 975 } 976 977 MGETHDR(m, M_DONTWAIT, MT_DATA); 978 if (m && max_linkhdr + maxlen >= MHLEN) { 979 MCLGET(m, M_DONTWAIT); 980 if ((m->m_flags & M_EXT) == 0) { 981 m_free(m); 982 m = NULL; 983 } 984 } 985 if (m == NULL) 986 return; 987 m->m_pkthdr.rcvif = NULL; 988 989 if (IN6_IS_ADDR_MULTICAST(&daddr6)) { 990 m->m_flags |= M_MCAST; 991 im6o.im6o_multicast_ifp = ifp; 992 im6o.im6o_multicast_hlim = 255; 993 im6o.im6o_multicast_loop = 0; 994 } 995 996 icmp6len = sizeof(*nd_na); 997 m->m_pkthdr.len = m->m_len = sizeof(struct ip6_hdr) + icmp6len; 998 m->m_data += max_linkhdr; /* or MH_ALIGN() equivalent? */ 999 1000 /* fill neighbor advertisement packet */ 1001 ip6 = mtod(m, struct ip6_hdr *); 1002 ip6->ip6_flow = 0; 1003 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 1004 ip6->ip6_vfc |= IPV6_VERSION; 1005 ip6->ip6_nxt = IPPROTO_ICMPV6; 1006 ip6->ip6_hlim = 255; 1007 if (IN6_IS_ADDR_UNSPECIFIED(&daddr6)) { 1008 /* reply to DAD */ 1009 daddr6.s6_addr16[0] = IPV6_ADDR_INT16_MLL; 1010 daddr6.s6_addr16[1] = 0; 1011 daddr6.s6_addr32[1] = 0; 1012 daddr6.s6_addr32[2] = 0; 1013 daddr6.s6_addr32[3] = IPV6_ADDR_INT32_ONE; 1014 if (in6_setscope(&daddr6, ifp, NULL)) 1015 goto bad; 1016 1017 flags &= ~ND_NA_FLAG_SOLICITED; 1018 } 1019 ip6->ip6_dst = daddr6; 1020 bzero(&dst_sa, sizeof(struct sockaddr_in6)); 1021 dst_sa.sin6_family = AF_INET6; 1022 dst_sa.sin6_len = sizeof(struct sockaddr_in6); 1023 dst_sa.sin6_addr = daddr6; 1024 1025 /* 1026 * Select a source whose scope is the same as that of the dest. 1027 */ 1028 bcopy(&dst_sa, &ro.ro_dst, sizeof(dst_sa)); 1029 error = in6_selectsrc(&dst_sa, NULL, NULL, &ro, NULL, NULL, &src); 1030 if (error) { 1031 char ip6buf[INET6_ADDRSTRLEN]; 1032 nd6log((LOG_DEBUG, "nd6_na_output: source can't be " 1033 "determined: dst=%s, error=%d\n", 1034 ip6_sprintf(ip6buf, &dst_sa.sin6_addr), error)); 1035 goto bad; 1036 } 1037 ip6->ip6_src = src; 1038 nd_na = (struct nd_neighbor_advert *)(ip6 + 1); 1039 nd_na->nd_na_type = ND_NEIGHBOR_ADVERT; 1040 nd_na->nd_na_code = 0; 1041 nd_na->nd_na_target = *taddr6; 1042 in6_clearscope(&nd_na->nd_na_target); /* XXX */ 1043 1044 /* 1045 * "tlladdr" indicates NS's condition for adding tlladdr or not. 1046 * see nd6_ns_input() for details. 1047 * Basically, if NS packet is sent to unicast/anycast addr, 1048 * target lladdr option SHOULD NOT be included. 1049 */ 1050 if (tlladdr) { 1051 /* 1052 * sdl0 != NULL indicates proxy NA. If we do proxy, use 1053 * lladdr in sdl0. If we are not proxying (sending NA for 1054 * my address) use lladdr configured for the interface. 1055 */ 1056 if (sdl0 == NULL) { 1057 if (ifp->if_carp) 1058 mac = (*carp_macmatch6_p)(ifp, m, taddr6); 1059 if (mac == NULL) 1060 mac = nd6_ifptomac(ifp); 1061 } else if (sdl0->sa_family == AF_LINK) { 1062 struct sockaddr_dl *sdl; 1063 sdl = (struct sockaddr_dl *)sdl0; 1064 if (sdl->sdl_alen == ifp->if_addrlen) 1065 mac = LLADDR(sdl); 1066 } 1067 } 1068 if (tlladdr && mac) { 1069 int optlen = sizeof(struct nd_opt_hdr) + ifp->if_addrlen; 1070 struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)(nd_na + 1); 1071 1072 /* roundup to 8 bytes alignment! */ 1073 optlen = (optlen + 7) & ~7; 1074 1075 m->m_pkthdr.len += optlen; 1076 m->m_len += optlen; 1077 icmp6len += optlen; 1078 bzero((caddr_t)nd_opt, optlen); 1079 nd_opt->nd_opt_type = ND_OPT_TARGET_LINKADDR; 1080 nd_opt->nd_opt_len = optlen >> 3; 1081 bcopy(mac, (caddr_t)(nd_opt + 1), ifp->if_addrlen); 1082 } else 1083 flags &= ~ND_NA_FLAG_OVERRIDE; 1084 1085 ip6->ip6_plen = htons((u_short)icmp6len); 1086 nd_na->nd_na_flags_reserved = flags; 1087 nd_na->nd_na_cksum = 0; 1088 nd_na->nd_na_cksum = 1089 in6_cksum(m, IPPROTO_ICMPV6, sizeof(struct ip6_hdr), icmp6len); 1090 1091 if (send_sendso_input_hook != NULL) { 1092 mtag = m_tag_get(PACKET_TAG_ND_OUTGOING, 1093 sizeof(unsigned short), M_NOWAIT); 1094 if (mtag == NULL) 1095 goto bad; 1096 *(unsigned short *)(mtag + 1) = nd_na->nd_na_type; 1097 m_tag_prepend(m, mtag); 1098 } 1099 1100 ip6_output(m, NULL, &ro, 0, &im6o, NULL, NULL); 1101 icmp6_ifstat_inc(ifp, ifs6_out_msg); 1102 icmp6_ifstat_inc(ifp, ifs6_out_neighboradvert); 1103 ICMP6STAT_INC(icp6s_outhist[ND_NEIGHBOR_ADVERT]); 1104 1105 if (ro.ro_rt) { /* we don't cache this route. */ 1106 RTFREE(ro.ro_rt); 1107 } 1108 return; 1109 1110 bad: 1111 if (ro.ro_rt) { 1112 RTFREE(ro.ro_rt); 1113 } 1114 m_freem(m); 1115 return; 1116 } 1117 1118 caddr_t 1119 nd6_ifptomac(struct ifnet *ifp) 1120 { 1121 switch (ifp->if_type) { 1122 case IFT_ARCNET: 1123 case IFT_ETHER: 1124 case IFT_FDDI: 1125 case IFT_IEEE1394: 1126 #ifdef IFT_L2VLAN 1127 case IFT_L2VLAN: 1128 #endif 1129 #ifdef IFT_IEEE80211 1130 case IFT_IEEE80211: 1131 #endif 1132 #ifdef IFT_CARP 1133 case IFT_CARP: 1134 #endif 1135 case IFT_INFINIBAND: 1136 case IFT_BRIDGE: 1137 case IFT_ISO88025: 1138 return IF_LLADDR(ifp); 1139 default: 1140 return NULL; 1141 } 1142 } 1143 1144 struct dadq { 1145 TAILQ_ENTRY(dadq) dad_list; 1146 struct ifaddr *dad_ifa; 1147 int dad_count; /* max NS to send */ 1148 int dad_ns_tcount; /* # of trials to send NS */ 1149 int dad_ns_ocount; /* NS sent so far */ 1150 int dad_ns_icount; 1151 int dad_na_icount; 1152 struct callout dad_timer_ch; 1153 struct vnet *dad_vnet; 1154 }; 1155 1156 static VNET_DEFINE(TAILQ_HEAD(, dadq), dadq); 1157 VNET_DEFINE(int, dad_init) = 0; 1158 #define V_dadq VNET(dadq) 1159 #define V_dad_init VNET(dad_init) 1160 1161 static struct dadq * 1162 nd6_dad_find(struct ifaddr *ifa) 1163 { 1164 struct dadq *dp; 1165 1166 for (dp = V_dadq.tqh_first; dp; dp = dp->dad_list.tqe_next) { 1167 if (dp->dad_ifa == ifa) 1168 return dp; 1169 } 1170 return NULL; 1171 } 1172 1173 static void 1174 nd6_dad_starttimer(struct dadq *dp, int ticks) 1175 { 1176 1177 callout_reset(&dp->dad_timer_ch, ticks, 1178 (void (*)(void *))nd6_dad_timer, (void *)dp); 1179 } 1180 1181 static void 1182 nd6_dad_stoptimer(struct dadq *dp) 1183 { 1184 1185 callout_stop(&dp->dad_timer_ch); 1186 } 1187 1188 /* 1189 * Start Duplicate Address Detection (DAD) for specified interface address. 1190 */ 1191 void 1192 nd6_dad_start(struct ifaddr *ifa, int delay) 1193 { 1194 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1195 struct dadq *dp; 1196 char ip6buf[INET6_ADDRSTRLEN]; 1197 1198 if (!V_dad_init) { 1199 TAILQ_INIT(&V_dadq); 1200 V_dad_init++; 1201 } 1202 1203 /* 1204 * If we don't need DAD, don't do it. 1205 * There are several cases: 1206 * - DAD is disabled (ip6_dad_count == 0) 1207 * - the interface address is anycast 1208 */ 1209 if (!(ia->ia6_flags & IN6_IFF_TENTATIVE)) { 1210 log(LOG_DEBUG, 1211 "nd6_dad_start: called with non-tentative address " 1212 "%s(%s)\n", 1213 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr), 1214 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1215 return; 1216 } 1217 if (ia->ia6_flags & IN6_IFF_ANYCAST) { 1218 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1219 return; 1220 } 1221 if (!V_ip6_dad_count) { 1222 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1223 return; 1224 } 1225 if (ifa->ifa_ifp == NULL) 1226 panic("nd6_dad_start: ifa->ifa_ifp == NULL"); 1227 if (!(ifa->ifa_ifp->if_flags & IFF_UP)) { 1228 return; 1229 } 1230 if (ND_IFINFO(ifa->ifa_ifp)->flags & ND6_IFF_IFDISABLED) 1231 return; 1232 if (nd6_dad_find(ifa) != NULL) { 1233 /* DAD already in progress */ 1234 return; 1235 } 1236 1237 dp = malloc(sizeof(*dp), M_IP6NDP, M_NOWAIT); 1238 if (dp == NULL) { 1239 log(LOG_ERR, "nd6_dad_start: memory allocation failed for " 1240 "%s(%s)\n", 1241 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr), 1242 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1243 return; 1244 } 1245 bzero(dp, sizeof(*dp)); 1246 callout_init(&dp->dad_timer_ch, 0); 1247 #ifdef VIMAGE 1248 dp->dad_vnet = curvnet; 1249 #endif 1250 TAILQ_INSERT_TAIL(&V_dadq, (struct dadq *)dp, dad_list); 1251 1252 nd6log((LOG_DEBUG, "%s: starting DAD for %s\n", if_name(ifa->ifa_ifp), 1253 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr))); 1254 1255 /* 1256 * Send NS packet for DAD, ip6_dad_count times. 1257 * Note that we must delay the first transmission, if this is the 1258 * first packet to be sent from the interface after interface 1259 * (re)initialization. 1260 */ 1261 dp->dad_ifa = ifa; 1262 ifa_ref(ifa); /* just for safety */ 1263 dp->dad_count = V_ip6_dad_count; 1264 dp->dad_ns_icount = dp->dad_na_icount = 0; 1265 dp->dad_ns_ocount = dp->dad_ns_tcount = 0; 1266 if (delay == 0) { 1267 nd6_dad_ns_output(dp, ifa); 1268 nd6_dad_starttimer(dp, 1269 (long)ND_IFINFO(ifa->ifa_ifp)->retrans * hz / 1000); 1270 } else { 1271 nd6_dad_starttimer(dp, delay); 1272 } 1273 } 1274 1275 /* 1276 * terminate DAD unconditionally. used for address removals. 1277 */ 1278 void 1279 nd6_dad_stop(struct ifaddr *ifa) 1280 { 1281 struct dadq *dp; 1282 1283 if (!V_dad_init) 1284 return; 1285 dp = nd6_dad_find(ifa); 1286 if (!dp) { 1287 /* DAD wasn't started yet */ 1288 return; 1289 } 1290 1291 nd6_dad_stoptimer(dp); 1292 1293 TAILQ_REMOVE(&V_dadq, (struct dadq *)dp, dad_list); 1294 free(dp, M_IP6NDP); 1295 dp = NULL; 1296 ifa_free(ifa); 1297 } 1298 1299 static void 1300 nd6_dad_timer(struct dadq *dp) 1301 { 1302 CURVNET_SET(dp->dad_vnet); 1303 int s; 1304 struct ifaddr *ifa = dp->dad_ifa; 1305 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1306 char ip6buf[INET6_ADDRSTRLEN]; 1307 1308 s = splnet(); /* XXX */ 1309 1310 /* Sanity check */ 1311 if (ia == NULL) { 1312 log(LOG_ERR, "nd6_dad_timer: called with null parameter\n"); 1313 goto done; 1314 } 1315 if (ia->ia6_flags & IN6_IFF_DUPLICATED) { 1316 log(LOG_ERR, "nd6_dad_timer: called with duplicated address " 1317 "%s(%s)\n", 1318 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr), 1319 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1320 goto done; 1321 } 1322 if ((ia->ia6_flags & IN6_IFF_TENTATIVE) == 0) { 1323 log(LOG_ERR, "nd6_dad_timer: called with non-tentative address " 1324 "%s(%s)\n", 1325 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr), 1326 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1327 goto done; 1328 } 1329 1330 /* timeouted with IFF_{RUNNING,UP} check */ 1331 if (dp->dad_ns_tcount > V_dad_maxtry) { 1332 nd6log((LOG_INFO, "%s: could not run DAD, driver problem?\n", 1333 if_name(ifa->ifa_ifp))); 1334 1335 TAILQ_REMOVE(&V_dadq, (struct dadq *)dp, dad_list); 1336 free(dp, M_IP6NDP); 1337 dp = NULL; 1338 ifa_free(ifa); 1339 goto done; 1340 } 1341 1342 /* Need more checks? */ 1343 if (dp->dad_ns_ocount < dp->dad_count) { 1344 /* 1345 * We have more NS to go. Send NS packet for DAD. 1346 */ 1347 nd6_dad_ns_output(dp, ifa); 1348 nd6_dad_starttimer(dp, 1349 (long)ND_IFINFO(ifa->ifa_ifp)->retrans * hz / 1000); 1350 } else { 1351 /* 1352 * We have transmitted sufficient number of DAD packets. 1353 * See what we've got. 1354 */ 1355 int duplicate; 1356 1357 duplicate = 0; 1358 1359 if (dp->dad_na_icount) { 1360 /* 1361 * the check is in nd6_dad_na_input(), 1362 * but just in case 1363 */ 1364 duplicate++; 1365 } 1366 1367 if (dp->dad_ns_icount) { 1368 /* We've seen NS, means DAD has failed. */ 1369 duplicate++; 1370 } 1371 1372 if (duplicate) { 1373 /* (*dp) will be freed in nd6_dad_duplicated() */ 1374 dp = NULL; 1375 nd6_dad_duplicated(ifa); 1376 } else { 1377 /* 1378 * We are done with DAD. No NA came, no NS came. 1379 * No duplicate address found. 1380 */ 1381 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1382 1383 nd6log((LOG_DEBUG, 1384 "%s: DAD complete for %s - no duplicates found\n", 1385 if_name(ifa->ifa_ifp), 1386 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr))); 1387 1388 TAILQ_REMOVE(&V_dadq, (struct dadq *)dp, dad_list); 1389 free(dp, M_IP6NDP); 1390 dp = NULL; 1391 ifa_free(ifa); 1392 } 1393 } 1394 1395 done: 1396 splx(s); 1397 CURVNET_RESTORE(); 1398 } 1399 1400 void 1401 nd6_dad_duplicated(struct ifaddr *ifa) 1402 { 1403 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1404 struct ifnet *ifp; 1405 struct dadq *dp; 1406 char ip6buf[INET6_ADDRSTRLEN]; 1407 1408 dp = nd6_dad_find(ifa); 1409 if (dp == NULL) { 1410 log(LOG_ERR, "nd6_dad_duplicated: DAD structure not found\n"); 1411 return; 1412 } 1413 1414 log(LOG_ERR, "%s: DAD detected duplicate IPv6 address %s: " 1415 "NS in/out=%d/%d, NA in=%d\n", 1416 if_name(ifa->ifa_ifp), ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr), 1417 dp->dad_ns_icount, dp->dad_ns_ocount, dp->dad_na_icount); 1418 1419 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1420 ia->ia6_flags |= IN6_IFF_DUPLICATED; 1421 1422 /* We are done with DAD, with duplicate address found. (failure) */ 1423 nd6_dad_stoptimer(dp); 1424 1425 ifp = ifa->ifa_ifp; 1426 log(LOG_ERR, "%s: DAD complete for %s - duplicate found\n", 1427 if_name(ifp), ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr)); 1428 log(LOG_ERR, "%s: manual intervention required\n", 1429 if_name(ifp)); 1430 1431 /* 1432 * If the address is a link-local address formed from an interface 1433 * identifier based on the hardware address which is supposed to be 1434 * uniquely assigned (e.g., EUI-64 for an Ethernet interface), IP 1435 * operation on the interface SHOULD be disabled. 1436 * [RFC 4862, Section 5.4.5] 1437 */ 1438 if (IN6_IS_ADDR_LINKLOCAL(&ia->ia_addr.sin6_addr)) { 1439 struct in6_addr in6; 1440 1441 /* 1442 * To avoid over-reaction, we only apply this logic when we are 1443 * very sure that hardware addresses are supposed to be unique. 1444 */ 1445 switch (ifp->if_type) { 1446 case IFT_ETHER: 1447 case IFT_FDDI: 1448 case IFT_ATM: 1449 case IFT_IEEE1394: 1450 #ifdef IFT_IEEE80211 1451 case IFT_IEEE80211: 1452 #endif 1453 case IFT_INFINIBAND: 1454 in6 = ia->ia_addr.sin6_addr; 1455 if (in6_get_hw_ifid(ifp, &in6) == 0 && 1456 IN6_ARE_ADDR_EQUAL(&ia->ia_addr.sin6_addr, &in6)) { 1457 ND_IFINFO(ifp)->flags |= ND6_IFF_IFDISABLED; 1458 log(LOG_ERR, "%s: possible hardware address " 1459 "duplication detected, disable IPv6\n", 1460 if_name(ifp)); 1461 } 1462 break; 1463 } 1464 } 1465 1466 TAILQ_REMOVE(&V_dadq, (struct dadq *)dp, dad_list); 1467 free(dp, M_IP6NDP); 1468 dp = NULL; 1469 ifa_free(ifa); 1470 } 1471 1472 static void 1473 nd6_dad_ns_output(struct dadq *dp, struct ifaddr *ifa) 1474 { 1475 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1476 struct ifnet *ifp = ifa->ifa_ifp; 1477 1478 dp->dad_ns_tcount++; 1479 if ((ifp->if_flags & IFF_UP) == 0) { 1480 return; 1481 } 1482 if ((ifp->if_drv_flags & IFF_DRV_RUNNING) == 0) { 1483 return; 1484 } 1485 1486 dp->dad_ns_ocount++; 1487 nd6_ns_output(ifp, NULL, &ia->ia_addr.sin6_addr, NULL, 1); 1488 } 1489 1490 static void 1491 nd6_dad_ns_input(struct ifaddr *ifa) 1492 { 1493 struct in6_ifaddr *ia; 1494 struct ifnet *ifp; 1495 const struct in6_addr *taddr6; 1496 struct dadq *dp; 1497 int duplicate; 1498 1499 if (ifa == NULL) 1500 panic("ifa == NULL in nd6_dad_ns_input"); 1501 1502 ia = (struct in6_ifaddr *)ifa; 1503 ifp = ifa->ifa_ifp; 1504 taddr6 = &ia->ia_addr.sin6_addr; 1505 duplicate = 0; 1506 dp = nd6_dad_find(ifa); 1507 1508 /* Quickhack - completely ignore DAD NS packets */ 1509 if (V_dad_ignore_ns) { 1510 char ip6buf[INET6_ADDRSTRLEN]; 1511 nd6log((LOG_INFO, 1512 "nd6_dad_ns_input: ignoring DAD NS packet for " 1513 "address %s(%s)\n", ip6_sprintf(ip6buf, taddr6), 1514 if_name(ifa->ifa_ifp))); 1515 return; 1516 } 1517 1518 /* 1519 * if I'm yet to start DAD, someone else started using this address 1520 * first. I have a duplicate and you win. 1521 */ 1522 if (dp == NULL || dp->dad_ns_ocount == 0) 1523 duplicate++; 1524 1525 /* XXX more checks for loopback situation - see nd6_dad_timer too */ 1526 1527 if (duplicate) { 1528 dp = NULL; /* will be freed in nd6_dad_duplicated() */ 1529 nd6_dad_duplicated(ifa); 1530 } else { 1531 /* 1532 * not sure if I got a duplicate. 1533 * increment ns count and see what happens. 1534 */ 1535 if (dp) 1536 dp->dad_ns_icount++; 1537 } 1538 } 1539 1540 static void 1541 nd6_dad_na_input(struct ifaddr *ifa) 1542 { 1543 struct dadq *dp; 1544 1545 if (ifa == NULL) 1546 panic("ifa == NULL in nd6_dad_na_input"); 1547 1548 dp = nd6_dad_find(ifa); 1549 if (dp) 1550 dp->dad_na_icount++; 1551 1552 /* remove the address. */ 1553 nd6_dad_duplicated(ifa); 1554 } 1555