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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/9.2/sys/netinet6/nd6_nbr.c 252555 2013-07-03 09:25:29Z np $"); 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 static void nd6_na_output_fib(struct ifnet *, const struct in6_addr *, 89 const struct in6_addr *, u_long, int, struct sockaddr *, u_int); 90 91 VNET_DEFINE(int, dad_ignore_ns) = 0; /* ignore NS in DAD - specwise incorrect*/ 92 VNET_DEFINE(int, dad_maxtry) = 15; /* max # of *tries* to transmit DAD packet */ 93 #define V_dad_ignore_ns VNET(dad_ignore_ns) 94 #define V_dad_maxtry VNET(dad_maxtry) 95 96 /* 97 * Input a Neighbor Solicitation Message. 98 * 99 * Based on RFC 2461 100 * Based on RFC 2462 (duplicate address detection) 101 */ 102 void 103 nd6_ns_input(struct mbuf *m, int off, int icmp6len) 104 { 105 struct ifnet *ifp = m->m_pkthdr.rcvif; 106 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 107 struct nd_neighbor_solicit *nd_ns; 108 struct in6_addr saddr6 = ip6->ip6_src; 109 struct in6_addr daddr6 = ip6->ip6_dst; 110 struct in6_addr taddr6; 111 struct in6_addr myaddr6; 112 char *lladdr = NULL; 113 struct ifaddr *ifa = NULL; 114 int lladdrlen = 0; 115 int anycast = 0, proxy = 0, tentative = 0; 116 int tlladdr; 117 int rflag; 118 union nd_opts ndopts; 119 struct sockaddr_dl proxydl; 120 char ip6bufs[INET6_ADDRSTRLEN], ip6bufd[INET6_ADDRSTRLEN]; 121 122 rflag = (V_ip6_forwarding) ? ND_NA_FLAG_ROUTER : 0; 123 if (ND_IFINFO(ifp)->flags & ND6_IFF_ACCEPT_RTADV && V_ip6_norbit_raif) 124 rflag = 0; 125 #ifndef PULLDOWN_TEST 126 IP6_EXTHDR_CHECK(m, off, icmp6len,); 127 nd_ns = (struct nd_neighbor_solicit *)((caddr_t)ip6 + off); 128 #else 129 IP6_EXTHDR_GET(nd_ns, struct nd_neighbor_solicit *, m, off, icmp6len); 130 if (nd_ns == NULL) { 131 ICMP6STAT_INC(icp6s_tooshort); 132 return; 133 } 134 #endif 135 ip6 = mtod(m, struct ip6_hdr *); /* adjust pointer for safety */ 136 taddr6 = nd_ns->nd_ns_target; 137 if (in6_setscope(&taddr6, ifp, NULL) != 0) 138 goto bad; 139 140 if (ip6->ip6_hlim != 255) { 141 nd6log((LOG_ERR, 142 "nd6_ns_input: invalid hlim (%d) from %s to %s on %s\n", 143 ip6->ip6_hlim, ip6_sprintf(ip6bufs, &ip6->ip6_src), 144 ip6_sprintf(ip6bufd, &ip6->ip6_dst), if_name(ifp))); 145 goto bad; 146 } 147 148 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) { 149 /* dst has to be a solicited node multicast address. */ 150 if (daddr6.s6_addr16[0] == IPV6_ADDR_INT16_MLL && 151 /* don't check ifindex portion */ 152 daddr6.s6_addr32[1] == 0 && 153 daddr6.s6_addr32[2] == IPV6_ADDR_INT32_ONE && 154 daddr6.s6_addr8[12] == 0xff) { 155 ; /* good */ 156 } else { 157 nd6log((LOG_INFO, "nd6_ns_input: bad DAD packet " 158 "(wrong ip6 dst)\n")); 159 goto bad; 160 } 161 } else if (!V_nd6_onlink_ns_rfc4861) { 162 struct sockaddr_in6 src_sa6; 163 164 /* 165 * According to recent IETF discussions, it is not a good idea 166 * to accept a NS from an address which would not be deemed 167 * to be a neighbor otherwise. This point is expected to be 168 * clarified in future revisions of the specification. 169 */ 170 bzero(&src_sa6, sizeof(src_sa6)); 171 src_sa6.sin6_family = AF_INET6; 172 src_sa6.sin6_len = sizeof(src_sa6); 173 src_sa6.sin6_addr = saddr6; 174 if (nd6_is_addr_neighbor(&src_sa6, ifp) == 0) { 175 nd6log((LOG_INFO, "nd6_ns_input: " 176 "NS packet from non-neighbor\n")); 177 goto bad; 178 } 179 } 180 181 if (IN6_IS_ADDR_MULTICAST(&taddr6)) { 182 nd6log((LOG_INFO, "nd6_ns_input: bad NS target (multicast)\n")); 183 goto bad; 184 } 185 186 icmp6len -= sizeof(*nd_ns); 187 nd6_option_init(nd_ns + 1, icmp6len, &ndopts); 188 if (nd6_options(&ndopts) < 0) { 189 nd6log((LOG_INFO, 190 "nd6_ns_input: invalid ND option, ignored\n")); 191 /* nd6_options have incremented stats */ 192 goto freeit; 193 } 194 195 if (ndopts.nd_opts_src_lladdr) { 196 lladdr = (char *)(ndopts.nd_opts_src_lladdr + 1); 197 lladdrlen = ndopts.nd_opts_src_lladdr->nd_opt_len << 3; 198 } 199 200 if (IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_src) && lladdr) { 201 nd6log((LOG_INFO, "nd6_ns_input: bad DAD packet " 202 "(link-layer address option)\n")); 203 goto bad; 204 } 205 206 /* 207 * Attaching target link-layer address to the NA? 208 * (RFC 2461 7.2.4) 209 * 210 * NS IP dst is unicast/anycast MUST NOT add 211 * NS IP dst is solicited-node multicast MUST add 212 * 213 * In implementation, we add target link-layer address by default. 214 * We do not add one in MUST NOT cases. 215 */ 216 if (!IN6_IS_ADDR_MULTICAST(&daddr6)) 217 tlladdr = 0; 218 else 219 tlladdr = 1; 220 221 /* 222 * Target address (taddr6) must be either: 223 * (1) Valid unicast/anycast address for my receiving interface, 224 * (2) Unicast address for which I'm offering proxy service, or 225 * (3) "tentative" address on which DAD is being performed. 226 */ 227 /* (1) and (3) check. */ 228 if (ifp->if_carp) 229 ifa = (*carp_iamatch6_p)(ifp, &taddr6); 230 if (ifa == NULL) 231 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &taddr6); 232 233 /* (2) check. */ 234 if (ifa == NULL) { 235 struct rtentry *rt; 236 struct sockaddr_in6 tsin6; 237 int need_proxy; 238 #ifdef RADIX_MPATH 239 struct route_in6 ro; 240 #endif 241 242 bzero(&tsin6, sizeof tsin6); 243 tsin6.sin6_len = sizeof(struct sockaddr_in6); 244 tsin6.sin6_family = AF_INET6; 245 tsin6.sin6_addr = taddr6; 246 247 /* Always use the default FIB. */ 248 #ifdef RADIX_MPATH 249 bzero(&ro, sizeof(ro)); 250 ro.ro_dst = tsin6; 251 rtalloc_mpath_fib((struct route *)&ro, RTF_ANNOUNCE, 252 RT_DEFAULT_FIB); 253 rt = ro.ro_rt; 254 #else 255 rt = in6_rtalloc1((struct sockaddr *)&tsin6, 0, 0, 256 RT_DEFAULT_FIB); 257 #endif 258 need_proxy = (rt && (rt->rt_flags & RTF_ANNOUNCE) != 0 && 259 rt->rt_gateway->sa_family == AF_LINK); 260 if (rt != NULL) { 261 /* 262 * Make a copy while we can be sure that rt_gateway 263 * is still stable before unlocking to avoid lock 264 * order problems. proxydl will only be used if 265 * proxy will be set in the next block. 266 */ 267 if (need_proxy) 268 proxydl = *SDL(rt->rt_gateway); 269 RTFREE_LOCKED(rt); 270 } 271 if (need_proxy) { 272 /* 273 * proxy NDP for single entry 274 */ 275 ifa = (struct ifaddr *)in6ifa_ifpforlinklocal(ifp, 276 IN6_IFF_NOTREADY|IN6_IFF_ANYCAST); 277 if (ifa) 278 proxy = 1; 279 } 280 } 281 if (ifa == NULL) { 282 /* 283 * We've got an NS packet, and we don't have that adddress 284 * assigned for us. We MUST silently ignore it. 285 * See RFC2461 7.2.3. 286 */ 287 goto freeit; 288 } 289 myaddr6 = *IFA_IN6(ifa); 290 anycast = ((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_ANYCAST; 291 tentative = ((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_TENTATIVE; 292 if (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_DUPLICATED) 293 goto freeit; 294 295 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) { 296 nd6log((LOG_INFO, "nd6_ns_input: lladdrlen mismatch for %s " 297 "(if %d, NS packet %d)\n", 298 ip6_sprintf(ip6bufs, &taddr6), 299 ifp->if_addrlen, lladdrlen - 2)); 300 goto bad; 301 } 302 303 if (IN6_ARE_ADDR_EQUAL(&myaddr6, &saddr6)) { 304 nd6log((LOG_INFO, "nd6_ns_input: duplicate IP6 address %s\n", 305 ip6_sprintf(ip6bufs, &saddr6))); 306 goto freeit; 307 } 308 309 /* 310 * We have neighbor solicitation packet, with target address equals to 311 * one of my tentative address. 312 * 313 * src addr how to process? 314 * --- --- 315 * multicast of course, invalid (rejected in ip6_input) 316 * unicast somebody is doing address resolution -> ignore 317 * unspec dup address detection 318 * 319 * The processing is defined in RFC 2462. 320 */ 321 if (tentative) { 322 /* 323 * If source address is unspecified address, it is for 324 * duplicate address detection. 325 * 326 * If not, the packet is for addess resolution; 327 * silently ignore it. 328 */ 329 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) 330 nd6_dad_ns_input(ifa); 331 332 goto freeit; 333 } 334 335 /* 336 * If the source address is unspecified address, entries must not 337 * be created or updated. 338 * It looks that sender is performing DAD. Output NA toward 339 * all-node multicast address, to tell the sender that I'm using 340 * the address. 341 * S bit ("solicited") must be zero. 342 */ 343 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) { 344 struct in6_addr in6_all; 345 346 in6_all = in6addr_linklocal_allnodes; 347 if (in6_setscope(&in6_all, ifp, NULL) != 0) 348 goto bad; 349 nd6_na_output_fib(ifp, &in6_all, &taddr6, 350 ((anycast || proxy || !tlladdr) ? 0 : ND_NA_FLAG_OVERRIDE) | 351 rflag, tlladdr, proxy ? (struct sockaddr *)&proxydl : NULL, 352 M_GETFIB(m)); 353 goto freeit; 354 } 355 356 nd6_cache_lladdr(ifp, &saddr6, lladdr, lladdrlen, 357 ND_NEIGHBOR_SOLICIT, 0); 358 359 nd6_na_output_fib(ifp, &saddr6, &taddr6, 360 ((anycast || proxy || !tlladdr) ? 0 : ND_NA_FLAG_OVERRIDE) | 361 rflag | ND_NA_FLAG_SOLICITED, tlladdr, 362 proxy ? (struct sockaddr *)&proxydl : NULL, M_GETFIB(m)); 363 freeit: 364 if (ifa != NULL) 365 ifa_free(ifa); 366 m_freem(m); 367 return; 368 369 bad: 370 nd6log((LOG_ERR, "nd6_ns_input: src=%s\n", 371 ip6_sprintf(ip6bufs, &saddr6))); 372 nd6log((LOG_ERR, "nd6_ns_input: dst=%s\n", 373 ip6_sprintf(ip6bufs, &daddr6))); 374 nd6log((LOG_ERR, "nd6_ns_input: tgt=%s\n", 375 ip6_sprintf(ip6bufs, &taddr6))); 376 ICMP6STAT_INC(icp6s_badns); 377 if (ifa != NULL) 378 ifa_free(ifa); 379 m_freem(m); 380 } 381 382 /* 383 * Output a Neighbor Solicitation Message. Caller specifies: 384 * - ICMP6 header source IP6 address 385 * - ND6 header target IP6 address 386 * - ND6 header source datalink address 387 * 388 * Based on RFC 2461 389 * Based on RFC 2462 (duplicate address detection) 390 * 391 * ln - for source address determination 392 * dad - duplicate address detection 393 */ 394 void 395 nd6_ns_output(struct ifnet *ifp, const struct in6_addr *daddr6, 396 const struct in6_addr *taddr6, struct llentry *ln, int dad) 397 { 398 struct mbuf *m; 399 struct m_tag *mtag; 400 struct ip6_hdr *ip6; 401 struct nd_neighbor_solicit *nd_ns; 402 struct ip6_moptions im6o; 403 int icmp6len; 404 int maxlen; 405 caddr_t mac; 406 struct route_in6 ro; 407 408 if (IN6_IS_ADDR_MULTICAST(taddr6)) 409 return; 410 411 /* estimate the size of message */ 412 maxlen = sizeof(*ip6) + sizeof(*nd_ns); 413 maxlen += (sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7; 414 if (max_linkhdr + maxlen >= MCLBYTES) { 415 #ifdef DIAGNOSTIC 416 printf("nd6_ns_output: max_linkhdr + maxlen >= MCLBYTES " 417 "(%d + %d > %d)\n", max_linkhdr, maxlen, MCLBYTES); 418 #endif 419 return; 420 } 421 422 MGETHDR(m, M_DONTWAIT, MT_DATA); 423 if (m && max_linkhdr + maxlen >= MHLEN) { 424 MCLGET(m, M_DONTWAIT); 425 if ((m->m_flags & M_EXT) == 0) { 426 m_free(m); 427 m = NULL; 428 } 429 } 430 if (m == NULL) 431 return; 432 m->m_pkthdr.rcvif = NULL; 433 434 bzero(&ro, sizeof(ro)); 435 436 if (daddr6 == NULL || IN6_IS_ADDR_MULTICAST(daddr6)) { 437 m->m_flags |= M_MCAST; 438 im6o.im6o_multicast_ifp = ifp; 439 im6o.im6o_multicast_hlim = 255; 440 im6o.im6o_multicast_loop = 0; 441 } 442 443 icmp6len = sizeof(*nd_ns); 444 m->m_pkthdr.len = m->m_len = sizeof(*ip6) + icmp6len; 445 m->m_data += max_linkhdr; /* or MH_ALIGN() equivalent? */ 446 447 /* fill neighbor solicitation packet */ 448 ip6 = mtod(m, struct ip6_hdr *); 449 ip6->ip6_flow = 0; 450 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 451 ip6->ip6_vfc |= IPV6_VERSION; 452 /* ip6->ip6_plen will be set later */ 453 ip6->ip6_nxt = IPPROTO_ICMPV6; 454 ip6->ip6_hlim = 255; 455 if (daddr6) 456 ip6->ip6_dst = *daddr6; 457 else { 458 ip6->ip6_dst.s6_addr16[0] = IPV6_ADDR_INT16_MLL; 459 ip6->ip6_dst.s6_addr16[1] = 0; 460 ip6->ip6_dst.s6_addr32[1] = 0; 461 ip6->ip6_dst.s6_addr32[2] = IPV6_ADDR_INT32_ONE; 462 ip6->ip6_dst.s6_addr32[3] = taddr6->s6_addr32[3]; 463 ip6->ip6_dst.s6_addr8[12] = 0xff; 464 if (in6_setscope(&ip6->ip6_dst, ifp, NULL) != 0) 465 goto bad; 466 } 467 if (!dad) { 468 struct ifaddr *ifa; 469 470 /* 471 * RFC2461 7.2.2: 472 * "If the source address of the packet prompting the 473 * solicitation is the same as one of the addresses assigned 474 * to the outgoing interface, that address SHOULD be placed 475 * in the IP Source Address of the outgoing solicitation. 476 * Otherwise, any one of the addresses assigned to the 477 * interface should be used." 478 * 479 * We use the source address for the prompting packet 480 * (saddr6), if: 481 * - saddr6 is given from the caller (by giving "ln"), and 482 * - saddr6 belongs to the outgoing interface. 483 * Otherwise, we perform the source address selection as usual. 484 */ 485 struct in6_addr *hsrc; 486 487 hsrc = NULL; 488 if (ln != NULL) { 489 LLE_RLOCK(ln); 490 if (ln->la_hold != NULL) { 491 struct ip6_hdr *hip6; /* hold ip6 */ 492 493 /* 494 * assuming every packet in la_hold has the same IP 495 * header 496 */ 497 hip6 = mtod(ln->la_hold, struct ip6_hdr *); 498 /* XXX pullup? */ 499 if (sizeof(*hip6) < ln->la_hold->m_len) { 500 ip6->ip6_src = hip6->ip6_src; 501 hsrc = &hip6->ip6_src; 502 } 503 } 504 LLE_RUNLOCK(ln); 505 } 506 if (hsrc && (ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, 507 hsrc)) != NULL) { 508 /* ip6_src set already. */ 509 ifa_free(ifa); 510 } else { 511 int error; 512 struct sockaddr_in6 dst_sa; 513 struct in6_addr src_in; 514 struct ifnet *oifp; 515 516 bzero(&dst_sa, sizeof(dst_sa)); 517 dst_sa.sin6_family = AF_INET6; 518 dst_sa.sin6_len = sizeof(dst_sa); 519 dst_sa.sin6_addr = ip6->ip6_dst; 520 521 oifp = ifp; 522 error = in6_selectsrc(&dst_sa, NULL, 523 NULL, &ro, NULL, &oifp, &src_in); 524 if (error) { 525 char ip6buf[INET6_ADDRSTRLEN]; 526 nd6log((LOG_DEBUG, 527 "nd6_ns_output: source can't be " 528 "determined: dst=%s, error=%d\n", 529 ip6_sprintf(ip6buf, &dst_sa.sin6_addr), 530 error)); 531 goto bad; 532 } 533 ip6->ip6_src = src_in; 534 } 535 } else { 536 /* 537 * Source address for DAD packet must always be IPv6 538 * unspecified address. (0::0) 539 * We actually don't have to 0-clear the address (we did it 540 * above), but we do so here explicitly to make the intention 541 * clearer. 542 */ 543 bzero(&ip6->ip6_src, sizeof(ip6->ip6_src)); 544 } 545 nd_ns = (struct nd_neighbor_solicit *)(ip6 + 1); 546 nd_ns->nd_ns_type = ND_NEIGHBOR_SOLICIT; 547 nd_ns->nd_ns_code = 0; 548 nd_ns->nd_ns_reserved = 0; 549 nd_ns->nd_ns_target = *taddr6; 550 in6_clearscope(&nd_ns->nd_ns_target); /* XXX */ 551 552 /* 553 * Add source link-layer address option. 554 * 555 * spec implementation 556 * --- --- 557 * DAD packet MUST NOT do not add the option 558 * there's no link layer address: 559 * impossible do not add the option 560 * there's link layer address: 561 * Multicast NS MUST add one add the option 562 * Unicast NS SHOULD add one add the option 563 */ 564 if (!dad && (mac = nd6_ifptomac(ifp))) { 565 int optlen = sizeof(struct nd_opt_hdr) + ifp->if_addrlen; 566 struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)(nd_ns + 1); 567 /* 8 byte alignments... */ 568 optlen = (optlen + 7) & ~7; 569 570 m->m_pkthdr.len += optlen; 571 m->m_len += optlen; 572 icmp6len += optlen; 573 bzero((caddr_t)nd_opt, optlen); 574 nd_opt->nd_opt_type = ND_OPT_SOURCE_LINKADDR; 575 nd_opt->nd_opt_len = optlen >> 3; 576 bcopy(mac, (caddr_t)(nd_opt + 1), ifp->if_addrlen); 577 } 578 579 ip6->ip6_plen = htons((u_short)icmp6len); 580 nd_ns->nd_ns_cksum = 0; 581 nd_ns->nd_ns_cksum = 582 in6_cksum(m, IPPROTO_ICMPV6, sizeof(*ip6), icmp6len); 583 584 if (send_sendso_input_hook != NULL) { 585 mtag = m_tag_get(PACKET_TAG_ND_OUTGOING, 586 sizeof(unsigned short), M_NOWAIT); 587 if (mtag == NULL) 588 goto bad; 589 *(unsigned short *)(mtag + 1) = nd_ns->nd_ns_type; 590 m_tag_prepend(m, mtag); 591 } 592 593 ip6_output(m, NULL, &ro, dad ? IPV6_UNSPECSRC : 0, &im6o, NULL, NULL); 594 icmp6_ifstat_inc(ifp, ifs6_out_msg); 595 icmp6_ifstat_inc(ifp, ifs6_out_neighborsolicit); 596 ICMP6STAT_INC(icp6s_outhist[ND_NEIGHBOR_SOLICIT]); 597 598 /* We don't cache this route. */ 599 RO_RTFREE(&ro); 600 601 return; 602 603 bad: 604 if (ro.ro_rt) { 605 RTFREE(ro.ro_rt); 606 } 607 m_freem(m); 608 return; 609 } 610 611 /* 612 * Neighbor advertisement input handling. 613 * 614 * Based on RFC 2461 615 * Based on RFC 2462 (duplicate address detection) 616 * 617 * the following items are not implemented yet: 618 * - proxy advertisement delay rule (RFC2461 7.2.8, last paragraph, SHOULD) 619 * - anycast advertisement delay rule (RFC2461 7.2.7, SHOULD) 620 */ 621 void 622 nd6_na_input(struct mbuf *m, int off, int icmp6len) 623 { 624 struct ifnet *ifp = m->m_pkthdr.rcvif; 625 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 626 struct nd_neighbor_advert *nd_na; 627 struct in6_addr daddr6 = ip6->ip6_dst; 628 struct in6_addr taddr6; 629 int flags; 630 int is_router; 631 int is_solicited; 632 int is_override; 633 char *lladdr = NULL; 634 int lladdrlen = 0; 635 int checklink = 0; 636 struct ifaddr *ifa; 637 struct llentry *ln = NULL; 638 union nd_opts ndopts; 639 struct mbuf *chain = NULL; 640 struct m_tag *mtag; 641 struct sockaddr_in6 sin6; 642 char ip6bufs[INET6_ADDRSTRLEN], ip6bufd[INET6_ADDRSTRLEN]; 643 644 if (ip6->ip6_hlim != 255) { 645 nd6log((LOG_ERR, 646 "nd6_na_input: invalid hlim (%d) from %s to %s on %s\n", 647 ip6->ip6_hlim, ip6_sprintf(ip6bufs, &ip6->ip6_src), 648 ip6_sprintf(ip6bufd, &ip6->ip6_dst), if_name(ifp))); 649 goto bad; 650 } 651 652 #ifndef PULLDOWN_TEST 653 IP6_EXTHDR_CHECK(m, off, icmp6len,); 654 nd_na = (struct nd_neighbor_advert *)((caddr_t)ip6 + off); 655 #else 656 IP6_EXTHDR_GET(nd_na, struct nd_neighbor_advert *, m, off, icmp6len); 657 if (nd_na == NULL) { 658 ICMP6STAT_INC(icp6s_tooshort); 659 return; 660 } 661 #endif 662 663 flags = nd_na->nd_na_flags_reserved; 664 is_router = ((flags & ND_NA_FLAG_ROUTER) != 0); 665 is_solicited = ((flags & ND_NA_FLAG_SOLICITED) != 0); 666 is_override = ((flags & ND_NA_FLAG_OVERRIDE) != 0); 667 668 taddr6 = nd_na->nd_na_target; 669 if (in6_setscope(&taddr6, ifp, NULL)) 670 goto bad; /* XXX: impossible */ 671 672 if (IN6_IS_ADDR_MULTICAST(&taddr6)) { 673 nd6log((LOG_ERR, 674 "nd6_na_input: invalid target address %s\n", 675 ip6_sprintf(ip6bufs, &taddr6))); 676 goto bad; 677 } 678 if (IN6_IS_ADDR_MULTICAST(&daddr6)) 679 if (is_solicited) { 680 nd6log((LOG_ERR, 681 "nd6_na_input: a solicited adv is multicasted\n")); 682 goto bad; 683 } 684 685 icmp6len -= sizeof(*nd_na); 686 nd6_option_init(nd_na + 1, icmp6len, &ndopts); 687 if (nd6_options(&ndopts) < 0) { 688 nd6log((LOG_INFO, 689 "nd6_na_input: invalid ND option, ignored\n")); 690 /* nd6_options have incremented stats */ 691 goto freeit; 692 } 693 694 if (ndopts.nd_opts_tgt_lladdr) { 695 lladdr = (char *)(ndopts.nd_opts_tgt_lladdr + 1); 696 lladdrlen = ndopts.nd_opts_tgt_lladdr->nd_opt_len << 3; 697 } 698 699 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &taddr6); 700 701 /* 702 * Target address matches one of my interface address. 703 * 704 * If my address is tentative, this means that there's somebody 705 * already using the same address as mine. This indicates DAD failure. 706 * This is defined in RFC 2462. 707 * 708 * Otherwise, process as defined in RFC 2461. 709 */ 710 if (ifa 711 && (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_TENTATIVE)) { 712 ifa_free(ifa); 713 nd6_dad_na_input(ifa); 714 goto freeit; 715 } 716 717 /* Just for safety, maybe unnecessary. */ 718 if (ifa) { 719 ifa_free(ifa); 720 log(LOG_ERR, 721 "nd6_na_input: duplicate IP6 address %s\n", 722 ip6_sprintf(ip6bufs, &taddr6)); 723 goto freeit; 724 } 725 726 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) { 727 nd6log((LOG_INFO, "nd6_na_input: lladdrlen mismatch for %s " 728 "(if %d, NA packet %d)\n", ip6_sprintf(ip6bufs, &taddr6), 729 ifp->if_addrlen, lladdrlen - 2)); 730 goto bad; 731 } 732 733 /* 734 * If no neighbor cache entry is found, NA SHOULD silently be 735 * discarded. 736 */ 737 IF_AFDATA_LOCK(ifp); 738 ln = nd6_lookup(&taddr6, LLE_EXCLUSIVE, ifp); 739 IF_AFDATA_UNLOCK(ifp); 740 if (ln == NULL) { 741 goto freeit; 742 } 743 744 if (ln->ln_state == ND6_LLINFO_INCOMPLETE) { 745 /* 746 * If the link-layer has address, and no lladdr option came, 747 * discard the packet. 748 */ 749 if (ifp->if_addrlen && lladdr == NULL) { 750 goto freeit; 751 } 752 753 /* 754 * Record link-layer address, and update the state. 755 */ 756 bcopy(lladdr, &ln->ll_addr, ifp->if_addrlen); 757 ln->la_flags |= LLE_VALID; 758 EVENTHANDLER_INVOKE(lle_event, ln, LLENTRY_RESOLVED); 759 if (is_solicited) { 760 ln->ln_state = ND6_LLINFO_REACHABLE; 761 ln->ln_byhint = 0; 762 if (!ND6_LLINFO_PERMANENT(ln)) { 763 nd6_llinfo_settimer_locked(ln, 764 (long)ND_IFINFO(ln->lle_tbl->llt_ifp)->reachable * hz); 765 } 766 } else { 767 ln->ln_state = ND6_LLINFO_STALE; 768 nd6_llinfo_settimer_locked(ln, (long)V_nd6_gctimer * hz); 769 } 770 if ((ln->ln_router = is_router) != 0) { 771 /* 772 * This means a router's state has changed from 773 * non-reachable to probably reachable, and might 774 * affect the status of associated prefixes.. 775 */ 776 checklink = 1; 777 } 778 } else { 779 int llchange; 780 781 /* 782 * Check if the link-layer address has changed or not. 783 */ 784 if (lladdr == NULL) 785 llchange = 0; 786 else { 787 if (ln->la_flags & LLE_VALID) { 788 if (bcmp(lladdr, &ln->ll_addr, ifp->if_addrlen)) 789 llchange = 1; 790 else 791 llchange = 0; 792 } else 793 llchange = 1; 794 } 795 796 /* 797 * This is VERY complex. Look at it with care. 798 * 799 * override solicit lladdr llchange action 800 * (L: record lladdr) 801 * 802 * 0 0 n -- (2c) 803 * 0 0 y n (2b) L 804 * 0 0 y y (1) REACHABLE->STALE 805 * 0 1 n -- (2c) *->REACHABLE 806 * 0 1 y n (2b) L *->REACHABLE 807 * 0 1 y y (1) REACHABLE->STALE 808 * 1 0 n -- (2a) 809 * 1 0 y n (2a) L 810 * 1 0 y y (2a) L *->STALE 811 * 1 1 n -- (2a) *->REACHABLE 812 * 1 1 y n (2a) L *->REACHABLE 813 * 1 1 y y (2a) L *->REACHABLE 814 */ 815 if (!is_override && (lladdr != NULL && llchange)) { /* (1) */ 816 /* 817 * If state is REACHABLE, make it STALE. 818 * no other updates should be done. 819 */ 820 if (ln->ln_state == ND6_LLINFO_REACHABLE) { 821 ln->ln_state = ND6_LLINFO_STALE; 822 nd6_llinfo_settimer_locked(ln, (long)V_nd6_gctimer * hz); 823 } 824 goto freeit; 825 } else if (is_override /* (2a) */ 826 || (!is_override && (lladdr != NULL && !llchange)) /* (2b) */ 827 || lladdr == NULL) { /* (2c) */ 828 /* 829 * Update link-local address, if any. 830 */ 831 if (lladdr != NULL) { 832 bcopy(lladdr, &ln->ll_addr, ifp->if_addrlen); 833 ln->la_flags |= LLE_VALID; 834 EVENTHANDLER_INVOKE(lle_event, ln, 835 LLENTRY_RESOLVED); 836 } 837 838 /* 839 * If solicited, make the state REACHABLE. 840 * If not solicited and the link-layer address was 841 * changed, make it STALE. 842 */ 843 if (is_solicited) { 844 ln->ln_state = ND6_LLINFO_REACHABLE; 845 ln->ln_byhint = 0; 846 if (!ND6_LLINFO_PERMANENT(ln)) { 847 nd6_llinfo_settimer_locked(ln, 848 (long)ND_IFINFO(ifp)->reachable * hz); 849 } 850 } else { 851 if (lladdr != NULL && llchange) { 852 ln->ln_state = ND6_LLINFO_STALE; 853 nd6_llinfo_settimer_locked(ln, 854 (long)V_nd6_gctimer * hz); 855 } 856 } 857 } 858 859 if (ln->ln_router && !is_router) { 860 /* 861 * The peer dropped the router flag. 862 * Remove the sender from the Default Router List and 863 * update the Destination Cache entries. 864 */ 865 struct nd_defrouter *dr; 866 struct in6_addr *in6; 867 868 in6 = &L3_ADDR_SIN6(ln)->sin6_addr; 869 870 /* 871 * Lock to protect the default router list. 872 * XXX: this might be unnecessary, since this function 873 * is only called under the network software interrupt 874 * context. However, we keep it just for safety. 875 */ 876 dr = defrouter_lookup(in6, ln->lle_tbl->llt_ifp); 877 if (dr) 878 defrtrlist_del(dr); 879 else if (ND_IFINFO(ln->lle_tbl->llt_ifp)->flags & 880 ND6_IFF_ACCEPT_RTADV) { 881 /* 882 * Even if the neighbor is not in the default 883 * router list, the neighbor may be used 884 * as a next hop for some destinations 885 * (e.g. redirect case). So we must 886 * call rt6_flush explicitly. 887 */ 888 rt6_flush(&ip6->ip6_src, ifp); 889 } 890 } 891 ln->ln_router = is_router; 892 } 893 /* XXX - QL 894 * Does this matter? 895 * rt->rt_flags &= ~RTF_REJECT; 896 */ 897 ln->la_asked = 0; 898 if (ln->la_hold) { 899 struct mbuf *m_hold, *m_hold_next; 900 901 /* 902 * reset the la_hold in advance, to explicitly 903 * prevent a la_hold lookup in nd6_output() 904 * (wouldn't happen, though...) 905 */ 906 for (m_hold = ln->la_hold, ln->la_hold = NULL; 907 m_hold; m_hold = m_hold_next) { 908 m_hold_next = m_hold->m_nextpkt; 909 m_hold->m_nextpkt = NULL; 910 /* 911 * we assume ifp is not a loopback here, so just set 912 * the 2nd argument as the 1st one. 913 */ 914 915 if (send_sendso_input_hook != NULL) { 916 mtag = m_tag_get(PACKET_TAG_ND_OUTGOING, 917 sizeof(unsigned short), M_NOWAIT); 918 if (mtag == NULL) 919 goto bad; 920 m_tag_prepend(m, mtag); 921 } 922 923 nd6_output_lle(ifp, ifp, m_hold, L3_ADDR_SIN6(ln), NULL, ln, &chain); 924 } 925 } 926 freeit: 927 if (ln != NULL) { 928 if (chain) 929 memcpy(&sin6, L3_ADDR_SIN6(ln), sizeof(sin6)); 930 LLE_WUNLOCK(ln); 931 932 if (chain) 933 nd6_output_flush(ifp, ifp, chain, &sin6, NULL); 934 } 935 if (checklink) 936 pfxlist_onlink_check(); 937 938 m_freem(m); 939 return; 940 941 bad: 942 if (ln != NULL) 943 LLE_WUNLOCK(ln); 944 945 ICMP6STAT_INC(icp6s_badna); 946 m_freem(m); 947 } 948 949 /* 950 * Neighbor advertisement output handling. 951 * 952 * Based on RFC 2461 953 * 954 * the following items are not implemented yet: 955 * - proxy advertisement delay rule (RFC2461 7.2.8, last paragraph, SHOULD) 956 * - anycast advertisement delay rule (RFC2461 7.2.7, SHOULD) 957 * 958 * tlladdr - 1 if include target link-layer address 959 * sdl0 - sockaddr_dl (= proxy NA) or NULL 960 */ 961 static void 962 nd6_na_output_fib(struct ifnet *ifp, const struct in6_addr *daddr6_0, 963 const struct in6_addr *taddr6, u_long flags, int tlladdr, 964 struct sockaddr *sdl0, u_int fibnum) 965 { 966 struct mbuf *m; 967 struct m_tag *mtag; 968 struct ifnet *oifp; 969 struct ip6_hdr *ip6; 970 struct nd_neighbor_advert *nd_na; 971 struct ip6_moptions im6o; 972 struct in6_addr src, daddr6; 973 struct sockaddr_in6 dst_sa; 974 int icmp6len, maxlen, error; 975 caddr_t mac = NULL; 976 struct route_in6 ro; 977 978 bzero(&ro, sizeof(ro)); 979 980 daddr6 = *daddr6_0; /* make a local copy for modification */ 981 982 /* estimate the size of message */ 983 maxlen = sizeof(*ip6) + sizeof(*nd_na); 984 maxlen += (sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7; 985 if (max_linkhdr + maxlen >= MCLBYTES) { 986 #ifdef DIAGNOSTIC 987 printf("nd6_na_output: max_linkhdr + maxlen >= MCLBYTES " 988 "(%d + %d > %d)\n", max_linkhdr, maxlen, MCLBYTES); 989 #endif 990 return; 991 } 992 993 MGETHDR(m, M_DONTWAIT, MT_DATA); 994 if (m && max_linkhdr + maxlen >= MHLEN) { 995 MCLGET(m, M_DONTWAIT); 996 if ((m->m_flags & M_EXT) == 0) { 997 m_free(m); 998 m = NULL; 999 } 1000 } 1001 if (m == NULL) 1002 return; 1003 m->m_pkthdr.rcvif = NULL; 1004 M_SETFIB(m, fibnum); 1005 1006 if (IN6_IS_ADDR_MULTICAST(&daddr6)) { 1007 m->m_flags |= M_MCAST; 1008 im6o.im6o_multicast_ifp = ifp; 1009 im6o.im6o_multicast_hlim = 255; 1010 im6o.im6o_multicast_loop = 0; 1011 } 1012 1013 icmp6len = sizeof(*nd_na); 1014 m->m_pkthdr.len = m->m_len = sizeof(struct ip6_hdr) + icmp6len; 1015 m->m_data += max_linkhdr; /* or MH_ALIGN() equivalent? */ 1016 1017 /* fill neighbor advertisement packet */ 1018 ip6 = mtod(m, struct ip6_hdr *); 1019 ip6->ip6_flow = 0; 1020 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 1021 ip6->ip6_vfc |= IPV6_VERSION; 1022 ip6->ip6_nxt = IPPROTO_ICMPV6; 1023 ip6->ip6_hlim = 255; 1024 if (IN6_IS_ADDR_UNSPECIFIED(&daddr6)) { 1025 /* reply to DAD */ 1026 daddr6.s6_addr16[0] = IPV6_ADDR_INT16_MLL; 1027 daddr6.s6_addr16[1] = 0; 1028 daddr6.s6_addr32[1] = 0; 1029 daddr6.s6_addr32[2] = 0; 1030 daddr6.s6_addr32[3] = IPV6_ADDR_INT32_ONE; 1031 if (in6_setscope(&daddr6, ifp, NULL)) 1032 goto bad; 1033 1034 flags &= ~ND_NA_FLAG_SOLICITED; 1035 } 1036 ip6->ip6_dst = daddr6; 1037 bzero(&dst_sa, sizeof(struct sockaddr_in6)); 1038 dst_sa.sin6_family = AF_INET6; 1039 dst_sa.sin6_len = sizeof(struct sockaddr_in6); 1040 dst_sa.sin6_addr = daddr6; 1041 1042 /* 1043 * Select a source whose scope is the same as that of the dest. 1044 */ 1045 bcopy(&dst_sa, &ro.ro_dst, sizeof(dst_sa)); 1046 oifp = ifp; 1047 error = in6_selectsrc(&dst_sa, NULL, NULL, &ro, NULL, &oifp, &src); 1048 if (error) { 1049 char ip6buf[INET6_ADDRSTRLEN]; 1050 nd6log((LOG_DEBUG, "nd6_na_output: source can't be " 1051 "determined: dst=%s, error=%d\n", 1052 ip6_sprintf(ip6buf, &dst_sa.sin6_addr), error)); 1053 goto bad; 1054 } 1055 ip6->ip6_src = src; 1056 nd_na = (struct nd_neighbor_advert *)(ip6 + 1); 1057 nd_na->nd_na_type = ND_NEIGHBOR_ADVERT; 1058 nd_na->nd_na_code = 0; 1059 nd_na->nd_na_target = *taddr6; 1060 in6_clearscope(&nd_na->nd_na_target); /* XXX */ 1061 1062 /* 1063 * "tlladdr" indicates NS's condition for adding tlladdr or not. 1064 * see nd6_ns_input() for details. 1065 * Basically, if NS packet is sent to unicast/anycast addr, 1066 * target lladdr option SHOULD NOT be included. 1067 */ 1068 if (tlladdr) { 1069 /* 1070 * sdl0 != NULL indicates proxy NA. If we do proxy, use 1071 * lladdr in sdl0. If we are not proxying (sending NA for 1072 * my address) use lladdr configured for the interface. 1073 */ 1074 if (sdl0 == NULL) { 1075 if (ifp->if_carp) 1076 mac = (*carp_macmatch6_p)(ifp, m, taddr6); 1077 if (mac == NULL) 1078 mac = nd6_ifptomac(ifp); 1079 } else if (sdl0->sa_family == AF_LINK) { 1080 struct sockaddr_dl *sdl; 1081 sdl = (struct sockaddr_dl *)sdl0; 1082 if (sdl->sdl_alen == ifp->if_addrlen) 1083 mac = LLADDR(sdl); 1084 } 1085 } 1086 if (tlladdr && mac) { 1087 int optlen = sizeof(struct nd_opt_hdr) + ifp->if_addrlen; 1088 struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)(nd_na + 1); 1089 1090 /* roundup to 8 bytes alignment! */ 1091 optlen = (optlen + 7) & ~7; 1092 1093 m->m_pkthdr.len += optlen; 1094 m->m_len += optlen; 1095 icmp6len += optlen; 1096 bzero((caddr_t)nd_opt, optlen); 1097 nd_opt->nd_opt_type = ND_OPT_TARGET_LINKADDR; 1098 nd_opt->nd_opt_len = optlen >> 3; 1099 bcopy(mac, (caddr_t)(nd_opt + 1), ifp->if_addrlen); 1100 } else 1101 flags &= ~ND_NA_FLAG_OVERRIDE; 1102 1103 ip6->ip6_plen = htons((u_short)icmp6len); 1104 nd_na->nd_na_flags_reserved = flags; 1105 nd_na->nd_na_cksum = 0; 1106 nd_na->nd_na_cksum = 1107 in6_cksum(m, IPPROTO_ICMPV6, sizeof(struct ip6_hdr), icmp6len); 1108 1109 if (send_sendso_input_hook != NULL) { 1110 mtag = m_tag_get(PACKET_TAG_ND_OUTGOING, 1111 sizeof(unsigned short), M_NOWAIT); 1112 if (mtag == NULL) 1113 goto bad; 1114 *(unsigned short *)(mtag + 1) = nd_na->nd_na_type; 1115 m_tag_prepend(m, mtag); 1116 } 1117 1118 ip6_output(m, NULL, &ro, 0, &im6o, NULL, NULL); 1119 icmp6_ifstat_inc(ifp, ifs6_out_msg); 1120 icmp6_ifstat_inc(ifp, ifs6_out_neighboradvert); 1121 ICMP6STAT_INC(icp6s_outhist[ND_NEIGHBOR_ADVERT]); 1122 1123 /* We don't cache this route. */ 1124 RO_RTFREE(&ro); 1125 1126 return; 1127 1128 bad: 1129 if (ro.ro_rt) { 1130 RTFREE(ro.ro_rt); 1131 } 1132 m_freem(m); 1133 return; 1134 } 1135 1136 #ifndef BURN_BRIDGES 1137 void 1138 nd6_na_output(struct ifnet *ifp, const struct in6_addr *daddr6_0, 1139 const struct in6_addr *taddr6, u_long flags, int tlladdr, 1140 struct sockaddr *sdl0) 1141 { 1142 1143 nd6_na_output_fib(ifp, daddr6_0, taddr6, flags, tlladdr, sdl0, 1144 RT_DEFAULT_FIB); 1145 } 1146 #endif 1147 1148 caddr_t 1149 nd6_ifptomac(struct ifnet *ifp) 1150 { 1151 switch (ifp->if_type) { 1152 case IFT_ARCNET: 1153 case IFT_ETHER: 1154 case IFT_FDDI: 1155 case IFT_IEEE1394: 1156 #ifdef IFT_L2VLAN 1157 case IFT_L2VLAN: 1158 #endif 1159 #ifdef IFT_IEEE80211 1160 case IFT_IEEE80211: 1161 #endif 1162 #ifdef IFT_CARP 1163 case IFT_CARP: 1164 #endif 1165 case IFT_INFINIBAND: 1166 case IFT_BRIDGE: 1167 case IFT_ISO88025: 1168 return IF_LLADDR(ifp); 1169 default: 1170 return NULL; 1171 } 1172 } 1173 1174 struct dadq { 1175 TAILQ_ENTRY(dadq) dad_list; 1176 struct ifaddr *dad_ifa; 1177 int dad_count; /* max NS to send */ 1178 int dad_ns_tcount; /* # of trials to send NS */ 1179 int dad_ns_ocount; /* NS sent so far */ 1180 int dad_ns_icount; 1181 int dad_na_icount; 1182 struct callout dad_timer_ch; 1183 struct vnet *dad_vnet; 1184 }; 1185 1186 static VNET_DEFINE(TAILQ_HEAD(, dadq), dadq); 1187 VNET_DEFINE(int, dad_init) = 0; 1188 #define V_dadq VNET(dadq) 1189 #define V_dad_init VNET(dad_init) 1190 1191 static struct dadq * 1192 nd6_dad_find(struct ifaddr *ifa) 1193 { 1194 struct dadq *dp; 1195 1196 TAILQ_FOREACH(dp, &V_dadq, dad_list) 1197 if (dp->dad_ifa == ifa) 1198 return (dp); 1199 1200 return (NULL); 1201 } 1202 1203 static void 1204 nd6_dad_starttimer(struct dadq *dp, int ticks) 1205 { 1206 1207 callout_reset(&dp->dad_timer_ch, ticks, 1208 (void (*)(void *))nd6_dad_timer, (void *)dp); 1209 } 1210 1211 static void 1212 nd6_dad_stoptimer(struct dadq *dp) 1213 { 1214 1215 callout_stop(&dp->dad_timer_ch); 1216 } 1217 1218 /* 1219 * Start Duplicate Address Detection (DAD) for specified interface address. 1220 */ 1221 void 1222 nd6_dad_start(struct ifaddr *ifa, int delay) 1223 { 1224 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1225 struct dadq *dp; 1226 char ip6buf[INET6_ADDRSTRLEN]; 1227 1228 if (!V_dad_init) { 1229 TAILQ_INIT(&V_dadq); 1230 V_dad_init++; 1231 } 1232 1233 /* 1234 * If we don't need DAD, don't do it. 1235 * There are several cases: 1236 * - DAD is disabled (ip6_dad_count == 0) 1237 * - the interface address is anycast 1238 */ 1239 if (!(ia->ia6_flags & IN6_IFF_TENTATIVE)) { 1240 log(LOG_DEBUG, 1241 "nd6_dad_start: called with non-tentative address " 1242 "%s(%s)\n", 1243 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr), 1244 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1245 return; 1246 } 1247 if (ia->ia6_flags & IN6_IFF_ANYCAST) { 1248 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1249 return; 1250 } 1251 if (!V_ip6_dad_count) { 1252 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1253 return; 1254 } 1255 if (ifa->ifa_ifp == NULL) 1256 panic("nd6_dad_start: ifa->ifa_ifp == NULL"); 1257 if (!(ifa->ifa_ifp->if_flags & IFF_UP)) { 1258 return; 1259 } 1260 if (ND_IFINFO(ifa->ifa_ifp)->flags & ND6_IFF_IFDISABLED) 1261 return; 1262 if (nd6_dad_find(ifa) != NULL) { 1263 /* DAD already in progress */ 1264 return; 1265 } 1266 1267 dp = malloc(sizeof(*dp), M_IP6NDP, M_NOWAIT); 1268 if (dp == NULL) { 1269 log(LOG_ERR, "nd6_dad_start: memory allocation failed for " 1270 "%s(%s)\n", 1271 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr), 1272 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1273 return; 1274 } 1275 bzero(dp, sizeof(*dp)); 1276 callout_init(&dp->dad_timer_ch, 0); 1277 #ifdef VIMAGE 1278 dp->dad_vnet = curvnet; 1279 #endif 1280 TAILQ_INSERT_TAIL(&V_dadq, (struct dadq *)dp, dad_list); 1281 1282 nd6log((LOG_DEBUG, "%s: starting DAD for %s\n", if_name(ifa->ifa_ifp), 1283 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr))); 1284 1285 /* 1286 * Send NS packet for DAD, ip6_dad_count times. 1287 * Note that we must delay the first transmission, if this is the 1288 * first packet to be sent from the interface after interface 1289 * (re)initialization. 1290 */ 1291 dp->dad_ifa = ifa; 1292 ifa_ref(ifa); /* just for safety */ 1293 dp->dad_count = V_ip6_dad_count; 1294 dp->dad_ns_icount = dp->dad_na_icount = 0; 1295 dp->dad_ns_ocount = dp->dad_ns_tcount = 0; 1296 if (delay == 0) { 1297 nd6_dad_ns_output(dp, ifa); 1298 nd6_dad_starttimer(dp, 1299 (long)ND_IFINFO(ifa->ifa_ifp)->retrans * hz / 1000); 1300 } else { 1301 nd6_dad_starttimer(dp, delay); 1302 } 1303 } 1304 1305 /* 1306 * terminate DAD unconditionally. used for address removals. 1307 */ 1308 void 1309 nd6_dad_stop(struct ifaddr *ifa) 1310 { 1311 struct dadq *dp; 1312 1313 if (!V_dad_init) 1314 return; 1315 dp = nd6_dad_find(ifa); 1316 if (!dp) { 1317 /* DAD wasn't started yet */ 1318 return; 1319 } 1320 1321 nd6_dad_stoptimer(dp); 1322 1323 TAILQ_REMOVE(&V_dadq, (struct dadq *)dp, dad_list); 1324 free(dp, M_IP6NDP); 1325 dp = NULL; 1326 ifa_free(ifa); 1327 } 1328 1329 static void 1330 nd6_dad_timer(struct dadq *dp) 1331 { 1332 CURVNET_SET(dp->dad_vnet); 1333 int s; 1334 struct ifaddr *ifa = dp->dad_ifa; 1335 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1336 char ip6buf[INET6_ADDRSTRLEN]; 1337 1338 s = splnet(); /* XXX */ 1339 1340 /* Sanity check */ 1341 if (ia == NULL) { 1342 log(LOG_ERR, "nd6_dad_timer: called with null parameter\n"); 1343 goto done; 1344 } 1345 if (ia->ia6_flags & IN6_IFF_DUPLICATED) { 1346 log(LOG_ERR, "nd6_dad_timer: called with duplicated address " 1347 "%s(%s)\n", 1348 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr), 1349 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1350 goto done; 1351 } 1352 if ((ia->ia6_flags & IN6_IFF_TENTATIVE) == 0) { 1353 log(LOG_ERR, "nd6_dad_timer: called with non-tentative address " 1354 "%s(%s)\n", 1355 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr), 1356 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1357 goto done; 1358 } 1359 1360 /* timeouted with IFF_{RUNNING,UP} check */ 1361 if (dp->dad_ns_tcount > V_dad_maxtry) { 1362 nd6log((LOG_INFO, "%s: could not run DAD, driver problem?\n", 1363 if_name(ifa->ifa_ifp))); 1364 1365 TAILQ_REMOVE(&V_dadq, (struct dadq *)dp, dad_list); 1366 free(dp, M_IP6NDP); 1367 dp = NULL; 1368 ifa_free(ifa); 1369 goto done; 1370 } 1371 1372 /* Need more checks? */ 1373 if (dp->dad_ns_ocount < dp->dad_count) { 1374 /* 1375 * We have more NS to go. Send NS packet for DAD. 1376 */ 1377 nd6_dad_ns_output(dp, ifa); 1378 nd6_dad_starttimer(dp, 1379 (long)ND_IFINFO(ifa->ifa_ifp)->retrans * hz / 1000); 1380 } else { 1381 /* 1382 * We have transmitted sufficient number of DAD packets. 1383 * See what we've got. 1384 */ 1385 int duplicate; 1386 1387 duplicate = 0; 1388 1389 if (dp->dad_na_icount) { 1390 /* 1391 * the check is in nd6_dad_na_input(), 1392 * but just in case 1393 */ 1394 duplicate++; 1395 } 1396 1397 if (dp->dad_ns_icount) { 1398 /* We've seen NS, means DAD has failed. */ 1399 duplicate++; 1400 } 1401 1402 if (duplicate) { 1403 /* (*dp) will be freed in nd6_dad_duplicated() */ 1404 dp = NULL; 1405 nd6_dad_duplicated(ifa); 1406 } else { 1407 /* 1408 * We are done with DAD. No NA came, no NS came. 1409 * No duplicate address found. 1410 */ 1411 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1412 1413 nd6log((LOG_DEBUG, 1414 "%s: DAD complete for %s - no duplicates found\n", 1415 if_name(ifa->ifa_ifp), 1416 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr))); 1417 1418 TAILQ_REMOVE(&V_dadq, (struct dadq *)dp, dad_list); 1419 free(dp, M_IP6NDP); 1420 dp = NULL; 1421 ifa_free(ifa); 1422 } 1423 } 1424 1425 done: 1426 splx(s); 1427 CURVNET_RESTORE(); 1428 } 1429 1430 void 1431 nd6_dad_duplicated(struct ifaddr *ifa) 1432 { 1433 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1434 struct ifnet *ifp; 1435 struct dadq *dp; 1436 char ip6buf[INET6_ADDRSTRLEN]; 1437 1438 dp = nd6_dad_find(ifa); 1439 if (dp == NULL) { 1440 log(LOG_ERR, "nd6_dad_duplicated: DAD structure not found\n"); 1441 return; 1442 } 1443 1444 log(LOG_ERR, "%s: DAD detected duplicate IPv6 address %s: " 1445 "NS in/out=%d/%d, NA in=%d\n", 1446 if_name(ifa->ifa_ifp), ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr), 1447 dp->dad_ns_icount, dp->dad_ns_ocount, dp->dad_na_icount); 1448 1449 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1450 ia->ia6_flags |= IN6_IFF_DUPLICATED; 1451 1452 /* We are done with DAD, with duplicate address found. (failure) */ 1453 nd6_dad_stoptimer(dp); 1454 1455 ifp = ifa->ifa_ifp; 1456 log(LOG_ERR, "%s: DAD complete for %s - duplicate found\n", 1457 if_name(ifp), ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr)); 1458 log(LOG_ERR, "%s: manual intervention required\n", 1459 if_name(ifp)); 1460 1461 /* 1462 * If the address is a link-local address formed from an interface 1463 * identifier based on the hardware address which is supposed to be 1464 * uniquely assigned (e.g., EUI-64 for an Ethernet interface), IP 1465 * operation on the interface SHOULD be disabled. 1466 * [RFC 4862, Section 5.4.5] 1467 */ 1468 if (IN6_IS_ADDR_LINKLOCAL(&ia->ia_addr.sin6_addr)) { 1469 struct in6_addr in6; 1470 1471 /* 1472 * To avoid over-reaction, we only apply this logic when we are 1473 * very sure that hardware addresses are supposed to be unique. 1474 */ 1475 switch (ifp->if_type) { 1476 case IFT_ETHER: 1477 case IFT_FDDI: 1478 case IFT_ATM: 1479 case IFT_IEEE1394: 1480 #ifdef IFT_IEEE80211 1481 case IFT_IEEE80211: 1482 #endif 1483 case IFT_INFINIBAND: 1484 in6 = ia->ia_addr.sin6_addr; 1485 if (in6_get_hw_ifid(ifp, &in6) == 0 && 1486 IN6_ARE_ADDR_EQUAL(&ia->ia_addr.sin6_addr, &in6)) { 1487 ND_IFINFO(ifp)->flags |= ND6_IFF_IFDISABLED; 1488 log(LOG_ERR, "%s: possible hardware address " 1489 "duplication detected, disable IPv6\n", 1490 if_name(ifp)); 1491 } 1492 break; 1493 } 1494 } 1495 1496 TAILQ_REMOVE(&V_dadq, (struct dadq *)dp, dad_list); 1497 free(dp, M_IP6NDP); 1498 dp = NULL; 1499 ifa_free(ifa); 1500 } 1501 1502 static void 1503 nd6_dad_ns_output(struct dadq *dp, struct ifaddr *ifa) 1504 { 1505 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1506 struct ifnet *ifp = ifa->ifa_ifp; 1507 1508 dp->dad_ns_tcount++; 1509 if ((ifp->if_flags & IFF_UP) == 0) { 1510 return; 1511 } 1512 if ((ifp->if_drv_flags & IFF_DRV_RUNNING) == 0) { 1513 return; 1514 } 1515 1516 dp->dad_ns_ocount++; 1517 nd6_ns_output(ifp, NULL, &ia->ia_addr.sin6_addr, NULL, 1); 1518 } 1519 1520 static void 1521 nd6_dad_ns_input(struct ifaddr *ifa) 1522 { 1523 struct in6_ifaddr *ia; 1524 struct ifnet *ifp; 1525 const struct in6_addr *taddr6; 1526 struct dadq *dp; 1527 int duplicate; 1528 1529 if (ifa == NULL) 1530 panic("ifa == NULL in nd6_dad_ns_input"); 1531 1532 ia = (struct in6_ifaddr *)ifa; 1533 ifp = ifa->ifa_ifp; 1534 taddr6 = &ia->ia_addr.sin6_addr; 1535 duplicate = 0; 1536 dp = nd6_dad_find(ifa); 1537 1538 /* Quickhack - completely ignore DAD NS packets */ 1539 if (V_dad_ignore_ns) { 1540 char ip6buf[INET6_ADDRSTRLEN]; 1541 nd6log((LOG_INFO, 1542 "nd6_dad_ns_input: ignoring DAD NS packet for " 1543 "address %s(%s)\n", ip6_sprintf(ip6buf, taddr6), 1544 if_name(ifa->ifa_ifp))); 1545 return; 1546 } 1547 1548 /* 1549 * if I'm yet to start DAD, someone else started using this address 1550 * first. I have a duplicate and you win. 1551 */ 1552 if (dp == NULL || dp->dad_ns_ocount == 0) 1553 duplicate++; 1554 1555 /* XXX more checks for loopback situation - see nd6_dad_timer too */ 1556 1557 if (duplicate) { 1558 dp = NULL; /* will be freed in nd6_dad_duplicated() */ 1559 nd6_dad_duplicated(ifa); 1560 } else { 1561 /* 1562 * not sure if I got a duplicate. 1563 * increment ns count and see what happens. 1564 */ 1565 if (dp) 1566 dp->dad_ns_icount++; 1567 } 1568 } 1569 1570 static void 1571 nd6_dad_na_input(struct ifaddr *ifa) 1572 { 1573 struct dadq *dp; 1574 1575 if (ifa == NULL) 1576 panic("ifa == NULL in nd6_dad_na_input"); 1577 1578 dp = nd6_dad_find(ifa); 1579 if (dp) 1580 dp->dad_na_icount++; 1581 1582 /* remove the address. */ 1583 nd6_dad_duplicated(ifa); 1584 }
Cache object: 8990a1b66d740f768cf3a3fbe351229a
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