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sys/netinet6/nd6_nbr.c
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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: releng/8.3/sys/netinet6/nd6_nbr.c 220773 2011-04-18 12:18:27Z bz $"); 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 77 #define SDL(s) ((struct sockaddr_dl *)s) 78 79 struct dadq; 80 static struct dadq *nd6_dad_find(struct ifaddr *); 81 static void nd6_dad_starttimer(struct dadq *, int); 82 static void nd6_dad_stoptimer(struct dadq *); 83 static void nd6_dad_timer(struct dadq *); 84 static void nd6_dad_ns_output(struct dadq *, struct ifaddr *); 85 static void nd6_dad_ns_input(struct ifaddr *); 86 static void nd6_dad_na_input(struct ifaddr *); 87 88 VNET_DEFINE(int, dad_ignore_ns) = 0; /* ignore NS in DAD - specwise incorrect*/ 89 VNET_DEFINE(int, dad_maxtry) = 15; /* max # of *tries* to transmit DAD packet */ 90 #define V_dad_ignore_ns VNET(dad_ignore_ns) 91 #define V_dad_maxtry VNET(dad_maxtry) 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(struct mbuf *m, int off, int icmp6len) 101 { 102 struct ifnet *ifp = m->m_pkthdr.rcvif; 103 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 104 struct nd_neighbor_solicit *nd_ns; 105 struct in6_addr saddr6 = ip6->ip6_src; 106 struct in6_addr daddr6 = ip6->ip6_dst; 107 struct in6_addr taddr6; 108 struct in6_addr myaddr6; 109 char *lladdr = NULL; 110 struct ifaddr *ifa = NULL; 111 int lladdrlen = 0; 112 int anycast = 0, proxy = 0, tentative = 0; 113 int tlladdr; 114 union nd_opts ndopts; 115 struct sockaddr_dl proxydl; 116 char ip6bufs[INET6_ADDRSTRLEN], ip6bufd[INET6_ADDRSTRLEN]; 117 118 #ifndef PULLDOWN_TEST 119 IP6_EXTHDR_CHECK(m, off, icmp6len,); 120 nd_ns = (struct nd_neighbor_solicit *)((caddr_t)ip6 + off); 121 #else 122 IP6_EXTHDR_GET(nd_ns, struct nd_neighbor_solicit *, m, off, icmp6len); 123 if (nd_ns == NULL) { 124 ICMP6STAT_INC(icp6s_tooshort); 125 return; 126 } 127 #endif 128 ip6 = mtod(m, struct ip6_hdr *); /* adjust pointer for safety */ 129 taddr6 = nd_ns->nd_ns_target; 130 if (in6_setscope(&taddr6, ifp, NULL) != 0) 131 goto bad; 132 133 if (ip6->ip6_hlim != 255) { 134 nd6log((LOG_ERR, 135 "nd6_ns_input: invalid hlim (%d) from %s to %s on %s\n", 136 ip6->ip6_hlim, ip6_sprintf(ip6bufs, &ip6->ip6_src), 137 ip6_sprintf(ip6bufd, &ip6->ip6_dst), if_name(ifp))); 138 goto bad; 139 } 140 141 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) { 142 /* dst has to be a solicited node multicast address. */ 143 if (daddr6.s6_addr16[0] == IPV6_ADDR_INT16_MLL && 144 /* don't check ifindex portion */ 145 daddr6.s6_addr32[1] == 0 && 146 daddr6.s6_addr32[2] == IPV6_ADDR_INT32_ONE && 147 daddr6.s6_addr8[12] == 0xff) { 148 ; /* good */ 149 } else { 150 nd6log((LOG_INFO, "nd6_ns_input: bad DAD packet " 151 "(wrong ip6 dst)\n")); 152 goto bad; 153 } 154 } else if (!V_nd6_onlink_ns_rfc4861) { 155 struct sockaddr_in6 src_sa6; 156 157 /* 158 * According to recent IETF discussions, it is not a good idea 159 * to accept a NS from an address which would not be deemed 160 * to be a neighbor otherwise. This point is expected to be 161 * clarified in future revisions of the specification. 162 */ 163 bzero(&src_sa6, sizeof(src_sa6)); 164 src_sa6.sin6_family = AF_INET6; 165 src_sa6.sin6_len = sizeof(src_sa6); 166 src_sa6.sin6_addr = saddr6; 167 if (nd6_is_addr_neighbor(&src_sa6, ifp) == 0) { 168 nd6log((LOG_INFO, "nd6_ns_input: " 169 "NS packet from non-neighbor\n")); 170 goto bad; 171 } 172 } 173 174 if (IN6_IS_ADDR_MULTICAST(&taddr6)) { 175 nd6log((LOG_INFO, "nd6_ns_input: bad NS target (multicast)\n")); 176 goto bad; 177 } 178 179 icmp6len -= sizeof(*nd_ns); 180 nd6_option_init(nd_ns + 1, icmp6len, &ndopts); 181 if (nd6_options(&ndopts) < 0) { 182 nd6log((LOG_INFO, 183 "nd6_ns_input: invalid ND option, ignored\n")); 184 /* nd6_options have incremented stats */ 185 goto freeit; 186 } 187 188 if (ndopts.nd_opts_src_lladdr) { 189 lladdr = (char *)(ndopts.nd_opts_src_lladdr + 1); 190 lladdrlen = ndopts.nd_opts_src_lladdr->nd_opt_len << 3; 191 } 192 193 if (IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_src) && lladdr) { 194 nd6log((LOG_INFO, "nd6_ns_input: bad DAD packet " 195 "(link-layer address option)\n")); 196 goto bad; 197 } 198 199 /* 200 * Attaching target link-layer address to the NA? 201 * (RFC 2461 7.2.4) 202 * 203 * NS IP dst is unicast/anycast MUST NOT add 204 * NS IP dst is solicited-node multicast MUST add 205 * 206 * In implementation, we add target link-layer address by default. 207 * We do not add one in MUST NOT cases. 208 */ 209 if (!IN6_IS_ADDR_MULTICAST(&daddr6)) 210 tlladdr = 0; 211 else 212 tlladdr = 1; 213 214 /* 215 * Target address (taddr6) must be either: 216 * (1) Valid unicast/anycast address for my receiving interface, 217 * (2) Unicast address for which I'm offering proxy service, or 218 * (3) "tentative" address on which DAD is being performed. 219 */ 220 /* (1) and (3) check. */ 221 if (ifp->if_carp) 222 ifa = (*carp_iamatch6_p)(ifp, &taddr6); 223 if (ifa == NULL) 224 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &taddr6); 225 226 /* (2) check. */ 227 if (ifa == NULL) { 228 struct rtentry *rt; 229 struct sockaddr_in6 tsin6; 230 int need_proxy; 231 #ifdef RADIX_MPATH 232 struct route_in6 ro; 233 #endif 234 235 bzero(&tsin6, sizeof tsin6); 236 tsin6.sin6_len = sizeof(struct sockaddr_in6); 237 tsin6.sin6_family = AF_INET6; 238 tsin6.sin6_addr = taddr6; 239 240 #ifdef RADIX_MPATH 241 bzero(&ro, sizeof(ro)); 242 ro.ro_dst = tsin6; 243 rtalloc_mpath((struct route *)&ro, RTF_ANNOUNCE); 244 rt = ro.ro_rt; 245 #else 246 rt = rtalloc1((struct sockaddr *)&tsin6, 0, 0); 247 #endif 248 need_proxy = (rt && (rt->rt_flags & RTF_ANNOUNCE) != 0 && 249 rt->rt_gateway->sa_family == AF_LINK); 250 if (rt != NULL) { 251 /* 252 * Make a copy while we can be sure that rt_gateway 253 * is still stable before unlocking to avoid lock 254 * order problems. proxydl will only be used if 255 * proxy will be set in the next block. 256 */ 257 if (need_proxy) 258 proxydl = *SDL(rt->rt_gateway); 259 RTFREE_LOCKED(rt); 260 } 261 if (need_proxy) { 262 /* 263 * proxy NDP for single entry 264 */ 265 ifa = (struct ifaddr *)in6ifa_ifpforlinklocal(ifp, 266 IN6_IFF_NOTREADY|IN6_IFF_ANYCAST); 267 if (ifa) 268 proxy = 1; 269 } 270 } 271 if (ifa == NULL) { 272 /* 273 * We've got an NS packet, and we don't have that adddress 274 * assigned for us. We MUST silently ignore it. 275 * See RFC2461 7.2.3. 276 */ 277 goto freeit; 278 } 279 myaddr6 = *IFA_IN6(ifa); 280 anycast = ((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_ANYCAST; 281 tentative = ((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_TENTATIVE; 282 if (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_DUPLICATED) 283 goto freeit; 284 285 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) { 286 nd6log((LOG_INFO, "nd6_ns_input: lladdrlen mismatch for %s " 287 "(if %d, NS packet %d)\n", 288 ip6_sprintf(ip6bufs, &taddr6), 289 ifp->if_addrlen, lladdrlen - 2)); 290 goto bad; 291 } 292 293 if (IN6_ARE_ADDR_EQUAL(&myaddr6, &saddr6)) { 294 nd6log((LOG_INFO, "nd6_ns_input: duplicate IP6 address %s\n", 295 ip6_sprintf(ip6bufs, &saddr6))); 296 goto freeit; 297 } 298 299 /* 300 * We have neighbor solicitation packet, with target address equals to 301 * one of my tentative address. 302 * 303 * src addr how to process? 304 * --- --- 305 * multicast of course, invalid (rejected in ip6_input) 306 * unicast somebody is doing address resolution -> ignore 307 * unspec dup address detection 308 * 309 * The processing is defined in RFC 2462. 310 */ 311 if (tentative) { 312 /* 313 * If source address is unspecified address, it is for 314 * duplicate address detection. 315 * 316 * If not, the packet is for addess resolution; 317 * silently ignore it. 318 */ 319 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) 320 nd6_dad_ns_input(ifa); 321 322 goto freeit; 323 } 324 325 /* 326 * If the source address is unspecified address, entries must not 327 * be created or updated. 328 * It looks that sender is performing DAD. Output NA toward 329 * all-node multicast address, to tell the sender that I'm using 330 * the address. 331 * S bit ("solicited") must be zero. 332 */ 333 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) { 334 struct in6_addr in6_all; 335 336 in6_all = in6addr_linklocal_allnodes; 337 if (in6_setscope(&in6_all, ifp, NULL) != 0) 338 goto bad; 339 nd6_na_output(ifp, &in6_all, &taddr6, 340 ((anycast || proxy || !tlladdr) ? 0 : ND_NA_FLAG_OVERRIDE) | 341 (V_ip6_forwarding ? ND_NA_FLAG_ROUTER : 0), 342 tlladdr, proxy ? (struct sockaddr *)&proxydl : NULL); 343 goto freeit; 344 } 345 346 nd6_cache_lladdr(ifp, &saddr6, lladdr, lladdrlen, 347 ND_NEIGHBOR_SOLICIT, 0); 348 349 nd6_na_output(ifp, &saddr6, &taddr6, 350 ((anycast || proxy || !tlladdr) ? 0 : ND_NA_FLAG_OVERRIDE) | 351 (V_ip6_forwarding ? ND_NA_FLAG_ROUTER : 0) | ND_NA_FLAG_SOLICITED, 352 tlladdr, proxy ? (struct sockaddr *)&proxydl : NULL); 353 freeit: 354 if (ifa != NULL) 355 ifa_free(ifa); 356 m_freem(m); 357 return; 358 359 bad: 360 nd6log((LOG_ERR, "nd6_ns_input: src=%s\n", 361 ip6_sprintf(ip6bufs, &saddr6))); 362 nd6log((LOG_ERR, "nd6_ns_input: dst=%s\n", 363 ip6_sprintf(ip6bufs, &daddr6))); 364 nd6log((LOG_ERR, "nd6_ns_input: tgt=%s\n", 365 ip6_sprintf(ip6bufs, &taddr6))); 366 ICMP6STAT_INC(icp6s_badns); 367 if (ifa != NULL) 368 ifa_free(ifa); 369 m_freem(m); 370 } 371 372 /* 373 * Output a Neighbor Solicitation Message. Caller specifies: 374 * - ICMP6 header source IP6 address 375 * - ND6 header target IP6 address 376 * - ND6 header source datalink address 377 * 378 * Based on RFC 2461 379 * Based on RFC 2462 (duplicate address detection) 380 * 381 * ln - for source address determination 382 * dad - duplicate address detection 383 */ 384 void 385 nd6_ns_output(struct ifnet *ifp, const struct in6_addr *daddr6, 386 const struct in6_addr *taddr6, struct llentry *ln, int dad) 387 { 388 struct mbuf *m; 389 struct ip6_hdr *ip6; 390 struct nd_neighbor_solicit *nd_ns; 391 struct ip6_moptions im6o; 392 int icmp6len; 393 int maxlen; 394 caddr_t mac; 395 struct route_in6 ro; 396 397 if (IN6_IS_ADDR_MULTICAST(taddr6)) 398 return; 399 400 /* estimate the size of message */ 401 maxlen = sizeof(*ip6) + sizeof(*nd_ns); 402 maxlen += (sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7; 403 if (max_linkhdr + maxlen >= MCLBYTES) { 404 #ifdef DIAGNOSTIC 405 printf("nd6_ns_output: max_linkhdr + maxlen >= MCLBYTES " 406 "(%d + %d > %d)\n", max_linkhdr, maxlen, MCLBYTES); 407 #endif 408 return; 409 } 410 411 MGETHDR(m, M_DONTWAIT, MT_DATA); 412 if (m && max_linkhdr + maxlen >= MHLEN) { 413 MCLGET(m, M_DONTWAIT); 414 if ((m->m_flags & M_EXT) == 0) { 415 m_free(m); 416 m = NULL; 417 } 418 } 419 if (m == NULL) 420 return; 421 m->m_pkthdr.rcvif = NULL; 422 423 bzero(&ro, sizeof(ro)); 424 425 if (daddr6 == NULL || IN6_IS_ADDR_MULTICAST(daddr6)) { 426 m->m_flags |= M_MCAST; 427 im6o.im6o_multicast_ifp = ifp; 428 im6o.im6o_multicast_hlim = 255; 429 im6o.im6o_multicast_loop = 0; 430 } 431 432 icmp6len = sizeof(*nd_ns); 433 m->m_pkthdr.len = m->m_len = sizeof(*ip6) + icmp6len; 434 m->m_data += max_linkhdr; /* or MH_ALIGN() equivalent? */ 435 436 /* fill neighbor solicitation packet */ 437 ip6 = mtod(m, struct ip6_hdr *); 438 ip6->ip6_flow = 0; 439 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 440 ip6->ip6_vfc |= IPV6_VERSION; 441 /* ip6->ip6_plen will be set later */ 442 ip6->ip6_nxt = IPPROTO_ICMPV6; 443 ip6->ip6_hlim = 255; 444 if (daddr6) 445 ip6->ip6_dst = *daddr6; 446 else { 447 ip6->ip6_dst.s6_addr16[0] = IPV6_ADDR_INT16_MLL; 448 ip6->ip6_dst.s6_addr16[1] = 0; 449 ip6->ip6_dst.s6_addr32[1] = 0; 450 ip6->ip6_dst.s6_addr32[2] = IPV6_ADDR_INT32_ONE; 451 ip6->ip6_dst.s6_addr32[3] = taddr6->s6_addr32[3]; 452 ip6->ip6_dst.s6_addr8[12] = 0xff; 453 if (in6_setscope(&ip6->ip6_dst, ifp, NULL) != 0) 454 goto bad; 455 } 456 if (!dad) { 457 struct ifaddr *ifa; 458 459 /* 460 * RFC2461 7.2.2: 461 * "If the source address of the packet prompting the 462 * solicitation is the same as one of the addresses assigned 463 * to the outgoing interface, that address SHOULD be placed 464 * in the IP Source Address of the outgoing solicitation. 465 * Otherwise, any one of the addresses assigned to the 466 * interface should be used." 467 * 468 * We use the source address for the prompting packet 469 * (saddr6), if: 470 * - saddr6 is given from the caller (by giving "ln"), and 471 * - saddr6 belongs to the outgoing interface. 472 * Otherwise, we perform the source address selection as usual. 473 */ 474 struct in6_addr *hsrc; 475 476 hsrc = NULL; 477 if (ln != NULL) { 478 LLE_RLOCK(ln); 479 if (ln->la_hold != NULL) { 480 struct ip6_hdr *hip6; /* hold ip6 */ 481 482 /* 483 * assuming every packet in la_hold has the same IP 484 * header 485 */ 486 hip6 = mtod(ln->la_hold, struct ip6_hdr *); 487 /* XXX pullup? */ 488 if (sizeof(*hip6) < ln->la_hold->m_len) { 489 ip6->ip6_src = hip6->ip6_src; 490 hsrc = &hip6->ip6_src; 491 } 492 } 493 LLE_RUNLOCK(ln); 494 } 495 if (hsrc && (ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, 496 hsrc)) != NULL) { 497 /* ip6_src set already. */ 498 ifa_free(ifa); 499 } else { 500 int error; 501 struct sockaddr_in6 dst_sa; 502 struct in6_addr src_in; 503 504 bzero(&dst_sa, sizeof(dst_sa)); 505 dst_sa.sin6_family = AF_INET6; 506 dst_sa.sin6_len = sizeof(dst_sa); 507 dst_sa.sin6_addr = ip6->ip6_dst; 508 509 error = in6_selectsrc(&dst_sa, NULL, 510 NULL, &ro, NULL, NULL, &src_in); 511 if (error) { 512 char ip6buf[INET6_ADDRSTRLEN]; 513 nd6log((LOG_DEBUG, 514 "nd6_ns_output: source can't be " 515 "determined: dst=%s, error=%d\n", 516 ip6_sprintf(ip6buf, &dst_sa.sin6_addr), 517 error)); 518 goto bad; 519 } 520 ip6->ip6_src = src_in; 521 } 522 } else { 523 /* 524 * Source address for DAD packet must always be IPv6 525 * unspecified address. (0::0) 526 * We actually don't have to 0-clear the address (we did it 527 * above), but we do so here explicitly to make the intention 528 * clearer. 529 */ 530 bzero(&ip6->ip6_src, sizeof(ip6->ip6_src)); 531 } 532 nd_ns = (struct nd_neighbor_solicit *)(ip6 + 1); 533 nd_ns->nd_ns_type = ND_NEIGHBOR_SOLICIT; 534 nd_ns->nd_ns_code = 0; 535 nd_ns->nd_ns_reserved = 0; 536 nd_ns->nd_ns_target = *taddr6; 537 in6_clearscope(&nd_ns->nd_ns_target); /* XXX */ 538 539 /* 540 * Add source link-layer address option. 541 * 542 * spec implementation 543 * --- --- 544 * DAD packet MUST NOT do not add the option 545 * there's no link layer address: 546 * impossible do not add the option 547 * there's link layer address: 548 * Multicast NS MUST add one add the option 549 * Unicast NS SHOULD add one add the option 550 */ 551 if (!dad && (mac = nd6_ifptomac(ifp))) { 552 int optlen = sizeof(struct nd_opt_hdr) + ifp->if_addrlen; 553 struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)(nd_ns + 1); 554 /* 8 byte alignments... */ 555 optlen = (optlen + 7) & ~7; 556 557 m->m_pkthdr.len += optlen; 558 m->m_len += optlen; 559 icmp6len += optlen; 560 bzero((caddr_t)nd_opt, optlen); 561 nd_opt->nd_opt_type = ND_OPT_SOURCE_LINKADDR; 562 nd_opt->nd_opt_len = optlen >> 3; 563 bcopy(mac, (caddr_t)(nd_opt + 1), ifp->if_addrlen); 564 } 565 566 ip6->ip6_plen = htons((u_short)icmp6len); 567 nd_ns->nd_ns_cksum = 0; 568 nd_ns->nd_ns_cksum = 569 in6_cksum(m, IPPROTO_ICMPV6, sizeof(*ip6), icmp6len); 570 571 ip6_output(m, NULL, &ro, dad ? IPV6_UNSPECSRC : 0, &im6o, NULL, NULL); 572 icmp6_ifstat_inc(ifp, ifs6_out_msg); 573 icmp6_ifstat_inc(ifp, ifs6_out_neighborsolicit); 574 ICMP6STAT_INC(icp6s_outhist[ND_NEIGHBOR_SOLICIT]); 575 576 if (ro.ro_rt) { /* we don't cache this route. */ 577 RTFREE(ro.ro_rt); 578 } 579 return; 580 581 bad: 582 if (ro.ro_rt) { 583 RTFREE(ro.ro_rt); 584 } 585 m_freem(m); 586 return; 587 } 588 589 /* 590 * Neighbor advertisement input handling. 591 * 592 * Based on RFC 2461 593 * Based on RFC 2462 (duplicate address detection) 594 * 595 * the following items are not implemented yet: 596 * - proxy advertisement delay rule (RFC2461 7.2.8, last paragraph, SHOULD) 597 * - anycast advertisement delay rule (RFC2461 7.2.7, SHOULD) 598 */ 599 void 600 nd6_na_input(struct mbuf *m, int off, int icmp6len) 601 { 602 struct ifnet *ifp = m->m_pkthdr.rcvif; 603 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 604 struct nd_neighbor_advert *nd_na; 605 struct in6_addr daddr6 = ip6->ip6_dst; 606 struct in6_addr taddr6; 607 int flags; 608 int is_router; 609 int is_solicited; 610 int is_override; 611 char *lladdr = NULL; 612 int lladdrlen = 0; 613 int checklink = 0; 614 struct ifaddr *ifa; 615 struct llentry *ln = NULL; 616 union nd_opts ndopts; 617 struct mbuf *chain = NULL; 618 struct sockaddr_in6 sin6; 619 char ip6bufs[INET6_ADDRSTRLEN], ip6bufd[INET6_ADDRSTRLEN]; 620 621 if (ip6->ip6_hlim != 255) { 622 nd6log((LOG_ERR, 623 "nd6_na_input: invalid hlim (%d) from %s to %s on %s\n", 624 ip6->ip6_hlim, ip6_sprintf(ip6bufs, &ip6->ip6_src), 625 ip6_sprintf(ip6bufd, &ip6->ip6_dst), if_name(ifp))); 626 goto bad; 627 } 628 629 #ifndef PULLDOWN_TEST 630 IP6_EXTHDR_CHECK(m, off, icmp6len,); 631 nd_na = (struct nd_neighbor_advert *)((caddr_t)ip6 + off); 632 #else 633 IP6_EXTHDR_GET(nd_na, struct nd_neighbor_advert *, m, off, icmp6len); 634 if (nd_na == NULL) { 635 ICMP6STAT_INC(icp6s_tooshort); 636 return; 637 } 638 #endif 639 640 flags = nd_na->nd_na_flags_reserved; 641 is_router = ((flags & ND_NA_FLAG_ROUTER) != 0); 642 is_solicited = ((flags & ND_NA_FLAG_SOLICITED) != 0); 643 is_override = ((flags & ND_NA_FLAG_OVERRIDE) != 0); 644 645 taddr6 = nd_na->nd_na_target; 646 if (in6_setscope(&taddr6, ifp, NULL)) 647 goto bad; /* XXX: impossible */ 648 649 if (IN6_IS_ADDR_MULTICAST(&taddr6)) { 650 nd6log((LOG_ERR, 651 "nd6_na_input: invalid target address %s\n", 652 ip6_sprintf(ip6bufs, &taddr6))); 653 goto bad; 654 } 655 if (IN6_IS_ADDR_MULTICAST(&daddr6)) 656 if (is_solicited) { 657 nd6log((LOG_ERR, 658 "nd6_na_input: a solicited adv is multicasted\n")); 659 goto bad; 660 } 661 662 icmp6len -= sizeof(*nd_na); 663 nd6_option_init(nd_na + 1, icmp6len, &ndopts); 664 if (nd6_options(&ndopts) < 0) { 665 nd6log((LOG_INFO, 666 "nd6_na_input: invalid ND option, ignored\n")); 667 /* nd6_options have incremented stats */ 668 goto freeit; 669 } 670 671 if (ndopts.nd_opts_tgt_lladdr) { 672 lladdr = (char *)(ndopts.nd_opts_tgt_lladdr + 1); 673 lladdrlen = ndopts.nd_opts_tgt_lladdr->nd_opt_len << 3; 674 } 675 676 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &taddr6); 677 678 /* 679 * Target address matches one of my interface address. 680 * 681 * If my address is tentative, this means that there's somebody 682 * already using the same address as mine. This indicates DAD failure. 683 * This is defined in RFC 2462. 684 * 685 * Otherwise, process as defined in RFC 2461. 686 */ 687 if (ifa 688 && (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_TENTATIVE)) { 689 ifa_free(ifa); 690 nd6_dad_na_input(ifa); 691 goto freeit; 692 } 693 694 /* Just for safety, maybe unnecessary. */ 695 if (ifa) { 696 ifa_free(ifa); 697 log(LOG_ERR, 698 "nd6_na_input: duplicate IP6 address %s\n", 699 ip6_sprintf(ip6bufs, &taddr6)); 700 goto freeit; 701 } 702 703 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) { 704 nd6log((LOG_INFO, "nd6_na_input: lladdrlen mismatch for %s " 705 "(if %d, NA packet %d)\n", ip6_sprintf(ip6bufs, &taddr6), 706 ifp->if_addrlen, lladdrlen - 2)); 707 goto bad; 708 } 709 710 /* 711 * If no neighbor cache entry is found, NA SHOULD silently be 712 * discarded. 713 */ 714 IF_AFDATA_LOCK(ifp); 715 ln = nd6_lookup(&taddr6, LLE_EXCLUSIVE, ifp); 716 IF_AFDATA_UNLOCK(ifp); 717 if (ln == NULL) { 718 goto freeit; 719 } 720 721 if (ln->ln_state == ND6_LLINFO_INCOMPLETE) { 722 /* 723 * If the link-layer has address, and no lladdr option came, 724 * discard the packet. 725 */ 726 if (ifp->if_addrlen && lladdr == NULL) { 727 goto freeit; 728 } 729 730 /* 731 * Record link-layer address, and update the state. 732 */ 733 bcopy(lladdr, &ln->ll_addr, ifp->if_addrlen); 734 ln->la_flags |= LLE_VALID; 735 if (is_solicited) { 736 ln->ln_state = ND6_LLINFO_REACHABLE; 737 ln->ln_byhint = 0; 738 if (!ND6_LLINFO_PERMANENT(ln)) { 739 nd6_llinfo_settimer_locked(ln, 740 (long)ND_IFINFO(ln->lle_tbl->llt_ifp)->reachable * hz); 741 } 742 } else { 743 ln->ln_state = ND6_LLINFO_STALE; 744 nd6_llinfo_settimer_locked(ln, (long)V_nd6_gctimer * hz); 745 } 746 if ((ln->ln_router = is_router) != 0) { 747 /* 748 * This means a router's state has changed from 749 * non-reachable to probably reachable, and might 750 * affect the status of associated prefixes.. 751 */ 752 checklink = 1; 753 } 754 } else { 755 int llchange; 756 757 /* 758 * Check if the link-layer address has changed or not. 759 */ 760 if (lladdr == NULL) 761 llchange = 0; 762 else { 763 if (ln->la_flags & LLE_VALID) { 764 if (bcmp(lladdr, &ln->ll_addr, ifp->if_addrlen)) 765 llchange = 1; 766 else 767 llchange = 0; 768 } else 769 llchange = 1; 770 } 771 772 /* 773 * This is VERY complex. Look at it with care. 774 * 775 * override solicit lladdr llchange action 776 * (L: record lladdr) 777 * 778 * 0 0 n -- (2c) 779 * 0 0 y n (2b) L 780 * 0 0 y y (1) REACHABLE->STALE 781 * 0 1 n -- (2c) *->REACHABLE 782 * 0 1 y n (2b) L *->REACHABLE 783 * 0 1 y y (1) REACHABLE->STALE 784 * 1 0 n -- (2a) 785 * 1 0 y n (2a) L 786 * 1 0 y y (2a) L *->STALE 787 * 1 1 n -- (2a) *->REACHABLE 788 * 1 1 y n (2a) L *->REACHABLE 789 * 1 1 y y (2a) L *->REACHABLE 790 */ 791 if (!is_override && (lladdr != NULL && llchange)) { /* (1) */ 792 /* 793 * If state is REACHABLE, make it STALE. 794 * no other updates should be done. 795 */ 796 if (ln->ln_state == ND6_LLINFO_REACHABLE) { 797 ln->ln_state = ND6_LLINFO_STALE; 798 nd6_llinfo_settimer_locked(ln, (long)V_nd6_gctimer * hz); 799 } 800 goto freeit; 801 } else if (is_override /* (2a) */ 802 || (!is_override && (lladdr != NULL && !llchange)) /* (2b) */ 803 || lladdr == NULL) { /* (2c) */ 804 /* 805 * Update link-local address, if any. 806 */ 807 if (lladdr != NULL) { 808 bcopy(lladdr, &ln->ll_addr, ifp->if_addrlen); 809 ln->la_flags |= LLE_VALID; 810 } 811 812 /* 813 * If solicited, make the state REACHABLE. 814 * If not solicited and the link-layer address was 815 * changed, make it STALE. 816 */ 817 if (is_solicited) { 818 ln->ln_state = ND6_LLINFO_REACHABLE; 819 ln->ln_byhint = 0; 820 if (!ND6_LLINFO_PERMANENT(ln)) { 821 nd6_llinfo_settimer_locked(ln, 822 (long)ND_IFINFO(ifp)->reachable * hz); 823 } 824 } else { 825 if (lladdr != NULL && llchange) { 826 ln->ln_state = ND6_LLINFO_STALE; 827 nd6_llinfo_settimer_locked(ln, 828 (long)V_nd6_gctimer * hz); 829 } 830 } 831 } 832 833 if (ln->ln_router && !is_router) { 834 /* 835 * The peer dropped the router flag. 836 * Remove the sender from the Default Router List and 837 * update the Destination Cache entries. 838 */ 839 struct nd_defrouter *dr; 840 struct in6_addr *in6; 841 842 in6 = &L3_ADDR_SIN6(ln)->sin6_addr; 843 844 /* 845 * Lock to protect the default router list. 846 * XXX: this might be unnecessary, since this function 847 * is only called under the network software interrupt 848 * context. However, we keep it just for safety. 849 */ 850 dr = defrouter_lookup(in6, ln->lle_tbl->llt_ifp); 851 if (dr) 852 defrtrlist_del(dr); 853 else if (!V_ip6_forwarding) { 854 /* 855 * Even if the neighbor is not in the default 856 * router list, the neighbor may be used 857 * as a next hop for some destinations 858 * (e.g. redirect case). So we must 859 * call rt6_flush explicitly. 860 */ 861 rt6_flush(&ip6->ip6_src, ifp); 862 } 863 } 864 ln->ln_router = is_router; 865 } 866 /* XXX - QL 867 * Does this matter? 868 * rt->rt_flags &= ~RTF_REJECT; 869 */ 870 ln->la_asked = 0; 871 if (ln->la_hold) { 872 struct mbuf *m_hold, *m_hold_next; 873 874 /* 875 * reset the la_hold in advance, to explicitly 876 * prevent a la_hold lookup in nd6_output() 877 * (wouldn't happen, though...) 878 */ 879 for (m_hold = ln->la_hold, ln->la_hold = NULL; 880 m_hold; m_hold = m_hold_next) { 881 m_hold_next = m_hold->m_nextpkt; 882 m_hold->m_nextpkt = NULL; 883 /* 884 * we assume ifp is not a loopback here, so just set 885 * the 2nd argument as the 1st one. 886 */ 887 nd6_output_lle(ifp, ifp, m_hold, L3_ADDR_SIN6(ln), NULL, ln, &chain); 888 } 889 } 890 freeit: 891 if (ln != NULL) { 892 if (chain) 893 memcpy(&sin6, L3_ADDR_SIN6(ln), sizeof(sin6)); 894 LLE_WUNLOCK(ln); 895 896 if (chain) 897 nd6_output_flush(ifp, ifp, chain, &sin6, NULL); 898 } 899 if (checklink) 900 pfxlist_onlink_check(); 901 902 m_freem(m); 903 return; 904 905 bad: 906 if (ln != NULL) 907 LLE_WUNLOCK(ln); 908 909 ICMP6STAT_INC(icp6s_badna); 910 m_freem(m); 911 } 912 913 /* 914 * Neighbor advertisement output handling. 915 * 916 * Based on RFC 2461 917 * 918 * the following items are not implemented yet: 919 * - proxy advertisement delay rule (RFC2461 7.2.8, last paragraph, SHOULD) 920 * - anycast advertisement delay rule (RFC2461 7.2.7, SHOULD) 921 * 922 * tlladdr - 1 if include target link-layer address 923 * sdl0 - sockaddr_dl (= proxy NA) or NULL 924 */ 925 void 926 nd6_na_output(struct ifnet *ifp, const struct in6_addr *daddr6_0, 927 const struct in6_addr *taddr6, u_long flags, int tlladdr, 928 struct sockaddr *sdl0) 929 { 930 struct mbuf *m; 931 struct ip6_hdr *ip6; 932 struct nd_neighbor_advert *nd_na; 933 struct ip6_moptions im6o; 934 struct in6_addr src, daddr6; 935 struct sockaddr_in6 dst_sa; 936 int icmp6len, maxlen, error; 937 caddr_t mac = NULL; 938 struct route_in6 ro; 939 940 bzero(&ro, sizeof(ro)); 941 942 daddr6 = *daddr6_0; /* make a local copy for modification */ 943 944 /* estimate the size of message */ 945 maxlen = sizeof(*ip6) + sizeof(*nd_na); 946 maxlen += (sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7; 947 if (max_linkhdr + maxlen >= MCLBYTES) { 948 #ifdef DIAGNOSTIC 949 printf("nd6_na_output: max_linkhdr + maxlen >= MCLBYTES " 950 "(%d + %d > %d)\n", max_linkhdr, maxlen, MCLBYTES); 951 #endif 952 return; 953 } 954 955 MGETHDR(m, M_DONTWAIT, MT_DATA); 956 if (m && max_linkhdr + maxlen >= MHLEN) { 957 MCLGET(m, M_DONTWAIT); 958 if ((m->m_flags & M_EXT) == 0) { 959 m_free(m); 960 m = NULL; 961 } 962 } 963 if (m == NULL) 964 return; 965 m->m_pkthdr.rcvif = NULL; 966 967 if (IN6_IS_ADDR_MULTICAST(&daddr6)) { 968 m->m_flags |= M_MCAST; 969 im6o.im6o_multicast_ifp = ifp; 970 im6o.im6o_multicast_hlim = 255; 971 im6o.im6o_multicast_loop = 0; 972 } 973 974 icmp6len = sizeof(*nd_na); 975 m->m_pkthdr.len = m->m_len = sizeof(struct ip6_hdr) + icmp6len; 976 m->m_data += max_linkhdr; /* or MH_ALIGN() equivalent? */ 977 978 /* fill neighbor advertisement packet */ 979 ip6 = mtod(m, struct ip6_hdr *); 980 ip6->ip6_flow = 0; 981 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 982 ip6->ip6_vfc |= IPV6_VERSION; 983 ip6->ip6_nxt = IPPROTO_ICMPV6; 984 ip6->ip6_hlim = 255; 985 if (IN6_IS_ADDR_UNSPECIFIED(&daddr6)) { 986 /* reply to DAD */ 987 daddr6.s6_addr16[0] = IPV6_ADDR_INT16_MLL; 988 daddr6.s6_addr16[1] = 0; 989 daddr6.s6_addr32[1] = 0; 990 daddr6.s6_addr32[2] = 0; 991 daddr6.s6_addr32[3] = IPV6_ADDR_INT32_ONE; 992 if (in6_setscope(&daddr6, ifp, NULL)) 993 goto bad; 994 995 flags &= ~ND_NA_FLAG_SOLICITED; 996 } 997 ip6->ip6_dst = daddr6; 998 bzero(&dst_sa, sizeof(struct sockaddr_in6)); 999 dst_sa.sin6_family = AF_INET6; 1000 dst_sa.sin6_len = sizeof(struct sockaddr_in6); 1001 dst_sa.sin6_addr = daddr6; 1002 1003 /* 1004 * Select a source whose scope is the same as that of the dest. 1005 */ 1006 bcopy(&dst_sa, &ro.ro_dst, sizeof(dst_sa)); 1007 error = in6_selectsrc(&dst_sa, NULL, NULL, &ro, NULL, NULL, &src); 1008 if (error) { 1009 char ip6buf[INET6_ADDRSTRLEN]; 1010 nd6log((LOG_DEBUG, "nd6_na_output: source can't be " 1011 "determined: dst=%s, error=%d\n", 1012 ip6_sprintf(ip6buf, &dst_sa.sin6_addr), error)); 1013 goto bad; 1014 } 1015 ip6->ip6_src = src; 1016 nd_na = (struct nd_neighbor_advert *)(ip6 + 1); 1017 nd_na->nd_na_type = ND_NEIGHBOR_ADVERT; 1018 nd_na->nd_na_code = 0; 1019 nd_na->nd_na_target = *taddr6; 1020 in6_clearscope(&nd_na->nd_na_target); /* XXX */ 1021 1022 /* 1023 * "tlladdr" indicates NS's condition for adding tlladdr or not. 1024 * see nd6_ns_input() for details. 1025 * Basically, if NS packet is sent to unicast/anycast addr, 1026 * target lladdr option SHOULD NOT be included. 1027 */ 1028 if (tlladdr) { 1029 /* 1030 * sdl0 != NULL indicates proxy NA. If we do proxy, use 1031 * lladdr in sdl0. If we are not proxying (sending NA for 1032 * my address) use lladdr configured for the interface. 1033 */ 1034 if (sdl0 == NULL) { 1035 if (ifp->if_carp) 1036 mac = (*carp_macmatch6_p)(ifp, m, taddr6); 1037 if (mac == NULL) 1038 mac = nd6_ifptomac(ifp); 1039 } else if (sdl0->sa_family == AF_LINK) { 1040 struct sockaddr_dl *sdl; 1041 sdl = (struct sockaddr_dl *)sdl0; 1042 if (sdl->sdl_alen == ifp->if_addrlen) 1043 mac = LLADDR(sdl); 1044 } 1045 } 1046 if (tlladdr && mac) { 1047 int optlen = sizeof(struct nd_opt_hdr) + ifp->if_addrlen; 1048 struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)(nd_na + 1); 1049 1050 /* roundup to 8 bytes alignment! */ 1051 optlen = (optlen + 7) & ~7; 1052 1053 m->m_pkthdr.len += optlen; 1054 m->m_len += optlen; 1055 icmp6len += optlen; 1056 bzero((caddr_t)nd_opt, optlen); 1057 nd_opt->nd_opt_type = ND_OPT_TARGET_LINKADDR; 1058 nd_opt->nd_opt_len = optlen >> 3; 1059 bcopy(mac, (caddr_t)(nd_opt + 1), ifp->if_addrlen); 1060 } else 1061 flags &= ~ND_NA_FLAG_OVERRIDE; 1062 1063 ip6->ip6_plen = htons((u_short)icmp6len); 1064 nd_na->nd_na_flags_reserved = flags; 1065 nd_na->nd_na_cksum = 0; 1066 nd_na->nd_na_cksum = 1067 in6_cksum(m, IPPROTO_ICMPV6, sizeof(struct ip6_hdr), icmp6len); 1068 1069 ip6_output(m, NULL, &ro, 0, &im6o, NULL, NULL); 1070 icmp6_ifstat_inc(ifp, ifs6_out_msg); 1071 icmp6_ifstat_inc(ifp, ifs6_out_neighboradvert); 1072 ICMP6STAT_INC(icp6s_outhist[ND_NEIGHBOR_ADVERT]); 1073 1074 if (ro.ro_rt) { /* we don't cache this route. */ 1075 RTFREE(ro.ro_rt); 1076 } 1077 return; 1078 1079 bad: 1080 if (ro.ro_rt) { 1081 RTFREE(ro.ro_rt); 1082 } 1083 m_freem(m); 1084 return; 1085 } 1086 1087 caddr_t 1088 nd6_ifptomac(struct ifnet *ifp) 1089 { 1090 switch (ifp->if_type) { 1091 case IFT_ARCNET: 1092 case IFT_ETHER: 1093 case IFT_FDDI: 1094 case IFT_IEEE1394: 1095 #ifdef IFT_L2VLAN 1096 case IFT_L2VLAN: 1097 #endif 1098 #ifdef IFT_IEEE80211 1099 case IFT_IEEE80211: 1100 #endif 1101 #ifdef IFT_CARP 1102 case IFT_CARP: 1103 #endif 1104 case IFT_BRIDGE: 1105 case IFT_ISO88025: 1106 return IF_LLADDR(ifp); 1107 default: 1108 return NULL; 1109 } 1110 } 1111 1112 struct dadq { 1113 TAILQ_ENTRY(dadq) dad_list; 1114 struct ifaddr *dad_ifa; 1115 int dad_count; /* max NS to send */ 1116 int dad_ns_tcount; /* # of trials to send NS */ 1117 int dad_ns_ocount; /* NS sent so far */ 1118 int dad_ns_icount; 1119 int dad_na_icount; 1120 struct callout dad_timer_ch; 1121 struct vnet *dad_vnet; 1122 }; 1123 1124 static VNET_DEFINE(TAILQ_HEAD(, dadq), dadq); 1125 VNET_DEFINE(int, dad_init) = 0; 1126 #define V_dadq VNET(dadq) 1127 #define V_dad_init VNET(dad_init) 1128 1129 static struct dadq * 1130 nd6_dad_find(struct ifaddr *ifa) 1131 { 1132 struct dadq *dp; 1133 1134 for (dp = V_dadq.tqh_first; dp; dp = dp->dad_list.tqe_next) { 1135 if (dp->dad_ifa == ifa) 1136 return dp; 1137 } 1138 return NULL; 1139 } 1140 1141 static void 1142 nd6_dad_starttimer(struct dadq *dp, int ticks) 1143 { 1144 1145 callout_reset(&dp->dad_timer_ch, ticks, 1146 (void (*)(void *))nd6_dad_timer, (void *)dp); 1147 } 1148 1149 static void 1150 nd6_dad_stoptimer(struct dadq *dp) 1151 { 1152 1153 callout_stop(&dp->dad_timer_ch); 1154 } 1155 1156 /* 1157 * Start Duplicate Address Detection (DAD) for specified interface address. 1158 */ 1159 void 1160 nd6_dad_start(struct ifaddr *ifa, int delay) 1161 { 1162 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1163 struct dadq *dp; 1164 char ip6buf[INET6_ADDRSTRLEN]; 1165 1166 if (!V_dad_init) { 1167 TAILQ_INIT(&V_dadq); 1168 V_dad_init++; 1169 } 1170 1171 /* 1172 * If we don't need DAD, don't do it. 1173 * There are several cases: 1174 * - DAD is disabled (ip6_dad_count == 0) 1175 * - the interface address is anycast 1176 */ 1177 if (!(ia->ia6_flags & IN6_IFF_TENTATIVE)) { 1178 log(LOG_DEBUG, 1179 "nd6_dad_start: called with non-tentative address " 1180 "%s(%s)\n", 1181 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr), 1182 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1183 return; 1184 } 1185 if (ia->ia6_flags & IN6_IFF_ANYCAST) { 1186 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1187 return; 1188 } 1189 if (!V_ip6_dad_count) { 1190 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1191 return; 1192 } 1193 if (ifa->ifa_ifp == NULL) 1194 panic("nd6_dad_start: ifa->ifa_ifp == NULL"); 1195 if (!(ifa->ifa_ifp->if_flags & IFF_UP)) { 1196 return; 1197 } 1198 if (nd6_dad_find(ifa) != NULL) { 1199 /* DAD already in progress */ 1200 return; 1201 } 1202 1203 dp = malloc(sizeof(*dp), M_IP6NDP, M_NOWAIT); 1204 if (dp == NULL) { 1205 log(LOG_ERR, "nd6_dad_start: memory allocation failed for " 1206 "%s(%s)\n", 1207 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr), 1208 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1209 return; 1210 } 1211 bzero(dp, sizeof(*dp)); 1212 callout_init(&dp->dad_timer_ch, 0); 1213 #ifdef VIMAGE 1214 dp->dad_vnet = curvnet; 1215 #endif 1216 TAILQ_INSERT_TAIL(&V_dadq, (struct dadq *)dp, dad_list); 1217 1218 nd6log((LOG_DEBUG, "%s: starting DAD for %s\n", if_name(ifa->ifa_ifp), 1219 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr))); 1220 1221 /* 1222 * Send NS packet for DAD, ip6_dad_count times. 1223 * Note that we must delay the first transmission, if this is the 1224 * first packet to be sent from the interface after interface 1225 * (re)initialization. 1226 */ 1227 dp->dad_ifa = ifa; 1228 ifa_ref(ifa); /* just for safety */ 1229 dp->dad_count = V_ip6_dad_count; 1230 dp->dad_ns_icount = dp->dad_na_icount = 0; 1231 dp->dad_ns_ocount = dp->dad_ns_tcount = 0; 1232 if (delay == 0) { 1233 nd6_dad_ns_output(dp, ifa); 1234 nd6_dad_starttimer(dp, 1235 (long)ND_IFINFO(ifa->ifa_ifp)->retrans * hz / 1000); 1236 } else { 1237 nd6_dad_starttimer(dp, delay); 1238 } 1239 } 1240 1241 /* 1242 * terminate DAD unconditionally. used for address removals. 1243 */ 1244 void 1245 nd6_dad_stop(struct ifaddr *ifa) 1246 { 1247 struct dadq *dp; 1248 1249 if (!V_dad_init) 1250 return; 1251 dp = nd6_dad_find(ifa); 1252 if (!dp) { 1253 /* DAD wasn't started yet */ 1254 return; 1255 } 1256 1257 nd6_dad_stoptimer(dp); 1258 1259 TAILQ_REMOVE(&V_dadq, (struct dadq *)dp, dad_list); 1260 free(dp, M_IP6NDP); 1261 dp = NULL; 1262 ifa_free(ifa); 1263 } 1264 1265 static void 1266 nd6_dad_timer(struct dadq *dp) 1267 { 1268 CURVNET_SET(dp->dad_vnet); 1269 int s; 1270 struct ifaddr *ifa = dp->dad_ifa; 1271 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1272 char ip6buf[INET6_ADDRSTRLEN]; 1273 1274 s = splnet(); /* XXX */ 1275 1276 /* Sanity check */ 1277 if (ia == NULL) { 1278 log(LOG_ERR, "nd6_dad_timer: called with null parameter\n"); 1279 goto done; 1280 } 1281 if (ia->ia6_flags & IN6_IFF_DUPLICATED) { 1282 log(LOG_ERR, "nd6_dad_timer: called with duplicated address " 1283 "%s(%s)\n", 1284 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr), 1285 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1286 goto done; 1287 } 1288 if ((ia->ia6_flags & IN6_IFF_TENTATIVE) == 0) { 1289 log(LOG_ERR, "nd6_dad_timer: called with non-tentative address " 1290 "%s(%s)\n", 1291 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr), 1292 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1293 goto done; 1294 } 1295 1296 /* timeouted with IFF_{RUNNING,UP} check */ 1297 if (dp->dad_ns_tcount > V_dad_maxtry) { 1298 nd6log((LOG_INFO, "%s: could not run DAD, driver problem?\n", 1299 if_name(ifa->ifa_ifp))); 1300 1301 TAILQ_REMOVE(&V_dadq, (struct dadq *)dp, dad_list); 1302 free(dp, M_IP6NDP); 1303 dp = NULL; 1304 ifa_free(ifa); 1305 goto done; 1306 } 1307 1308 /* Need more checks? */ 1309 if (dp->dad_ns_ocount < dp->dad_count) { 1310 /* 1311 * We have more NS to go. Send NS packet for DAD. 1312 */ 1313 nd6_dad_ns_output(dp, ifa); 1314 nd6_dad_starttimer(dp, 1315 (long)ND_IFINFO(ifa->ifa_ifp)->retrans * hz / 1000); 1316 } else { 1317 /* 1318 * We have transmitted sufficient number of DAD packets. 1319 * See what we've got. 1320 */ 1321 int duplicate; 1322 1323 duplicate = 0; 1324 1325 if (dp->dad_na_icount) { 1326 /* 1327 * the check is in nd6_dad_na_input(), 1328 * but just in case 1329 */ 1330 duplicate++; 1331 } 1332 1333 if (dp->dad_ns_icount) { 1334 /* We've seen NS, means DAD has failed. */ 1335 duplicate++; 1336 } 1337 1338 if (duplicate) { 1339 /* (*dp) will be freed in nd6_dad_duplicated() */ 1340 dp = NULL; 1341 nd6_dad_duplicated(ifa); 1342 } else { 1343 /* 1344 * We are done with DAD. No NA came, no NS came. 1345 * No duplicate address found. 1346 */ 1347 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1348 1349 nd6log((LOG_DEBUG, 1350 "%s: DAD complete for %s - no duplicates found\n", 1351 if_name(ifa->ifa_ifp), 1352 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr))); 1353 1354 TAILQ_REMOVE(&V_dadq, (struct dadq *)dp, dad_list); 1355 free(dp, M_IP6NDP); 1356 dp = NULL; 1357 ifa_free(ifa); 1358 } 1359 } 1360 1361 done: 1362 splx(s); 1363 CURVNET_RESTORE(); 1364 } 1365 1366 void 1367 nd6_dad_duplicated(struct ifaddr *ifa) 1368 { 1369 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1370 struct ifnet *ifp; 1371 struct dadq *dp; 1372 char ip6buf[INET6_ADDRSTRLEN]; 1373 1374 dp = nd6_dad_find(ifa); 1375 if (dp == NULL) { 1376 log(LOG_ERR, "nd6_dad_duplicated: DAD structure not found\n"); 1377 return; 1378 } 1379 1380 log(LOG_ERR, "%s: DAD detected duplicate IPv6 address %s: " 1381 "NS in/out=%d/%d, NA in=%d\n", 1382 if_name(ifa->ifa_ifp), ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr), 1383 dp->dad_ns_icount, dp->dad_ns_ocount, dp->dad_na_icount); 1384 1385 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1386 ia->ia6_flags |= IN6_IFF_DUPLICATED; 1387 1388 /* We are done with DAD, with duplicate address found. (failure) */ 1389 nd6_dad_stoptimer(dp); 1390 1391 ifp = ifa->ifa_ifp; 1392 log(LOG_ERR, "%s: DAD complete for %s - duplicate found\n", 1393 if_name(ifp), ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr)); 1394 log(LOG_ERR, "%s: manual intervention required\n", 1395 if_name(ifp)); 1396 1397 /* 1398 * If the address is a link-local address formed from an interface 1399 * identifier based on the hardware address which is supposed to be 1400 * uniquely assigned (e.g., EUI-64 for an Ethernet interface), IP 1401 * operation on the interface SHOULD be disabled. 1402 * [rfc2462bis-03 Section 5.4.5] 1403 */ 1404 if (IN6_IS_ADDR_LINKLOCAL(&ia->ia_addr.sin6_addr)) { 1405 struct in6_addr in6; 1406 1407 /* 1408 * To avoid over-reaction, we only apply this logic when we are 1409 * very sure that hardware addresses are supposed to be unique. 1410 */ 1411 switch (ifp->if_type) { 1412 case IFT_ETHER: 1413 case IFT_FDDI: 1414 case IFT_ATM: 1415 case IFT_IEEE1394: 1416 #ifdef IFT_IEEE80211 1417 case IFT_IEEE80211: 1418 #endif 1419 in6 = ia->ia_addr.sin6_addr; 1420 if (in6_get_hw_ifid(ifp, &in6) == 0 && 1421 IN6_ARE_ADDR_EQUAL(&ia->ia_addr.sin6_addr, &in6)) { 1422 ND_IFINFO(ifp)->flags |= ND6_IFF_IFDISABLED; 1423 log(LOG_ERR, "%s: possible hardware address " 1424 "duplication detected, disable IPv6\n", 1425 if_name(ifp)); 1426 } 1427 break; 1428 } 1429 } 1430 1431 TAILQ_REMOVE(&V_dadq, (struct dadq *)dp, dad_list); 1432 free(dp, M_IP6NDP); 1433 dp = NULL; 1434 ifa_free(ifa); 1435 } 1436 1437 static void 1438 nd6_dad_ns_output(struct dadq *dp, struct ifaddr *ifa) 1439 { 1440 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1441 struct ifnet *ifp = ifa->ifa_ifp; 1442 1443 dp->dad_ns_tcount++; 1444 if ((ifp->if_flags & IFF_UP) == 0) { 1445 return; 1446 } 1447 if ((ifp->if_drv_flags & IFF_DRV_RUNNING) == 0) { 1448 return; 1449 } 1450 1451 dp->dad_ns_ocount++; 1452 nd6_ns_output(ifp, NULL, &ia->ia_addr.sin6_addr, NULL, 1); 1453 } 1454 1455 static void 1456 nd6_dad_ns_input(struct ifaddr *ifa) 1457 { 1458 struct in6_ifaddr *ia; 1459 struct ifnet *ifp; 1460 const struct in6_addr *taddr6; 1461 struct dadq *dp; 1462 int duplicate; 1463 1464 if (ifa == NULL) 1465 panic("ifa == NULL in nd6_dad_ns_input"); 1466 1467 ia = (struct in6_ifaddr *)ifa; 1468 ifp = ifa->ifa_ifp; 1469 taddr6 = &ia->ia_addr.sin6_addr; 1470 duplicate = 0; 1471 dp = nd6_dad_find(ifa); 1472 1473 /* Quickhack - completely ignore DAD NS packets */ 1474 if (V_dad_ignore_ns) { 1475 char ip6buf[INET6_ADDRSTRLEN]; 1476 nd6log((LOG_INFO, 1477 "nd6_dad_ns_input: ignoring DAD NS packet for " 1478 "address %s(%s)\n", ip6_sprintf(ip6buf, taddr6), 1479 if_name(ifa->ifa_ifp))); 1480 return; 1481 } 1482 1483 /* 1484 * if I'm yet to start DAD, someone else started using this address 1485 * first. I have a duplicate and you win. 1486 */ 1487 if (dp == NULL || dp->dad_ns_ocount == 0) 1488 duplicate++; 1489 1490 /* XXX more checks for loopback situation - see nd6_dad_timer too */ 1491 1492 if (duplicate) { 1493 dp = NULL; /* will be freed in nd6_dad_duplicated() */ 1494 nd6_dad_duplicated(ifa); 1495 } else { 1496 /* 1497 * not sure if I got a duplicate. 1498 * increment ns count and see what happens. 1499 */ 1500 if (dp) 1501 dp->dad_ns_icount++; 1502 } 1503 } 1504 1505 static void 1506 nd6_dad_na_input(struct ifaddr *ifa) 1507 { 1508 struct dadq *dp; 1509 1510 if (ifa == NULL) 1511 panic("ifa == NULL in nd6_dad_na_input"); 1512 1513 dp = nd6_dad_find(ifa); 1514 if (dp) 1515 dp->dad_na_icount++; 1516 1517 /* remove the address. */ 1518 nd6_dad_duplicated(ifa); 1519 }
Cache object: 7f7748293bc8a72562912d4ba1dd61cc
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