nd6_nbr.c revision 281866
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: stable/10/sys/netinet6/nd6_nbr.c 281866 2015-04-22 19:41:29Z ae $"); 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 80struct dadq; 81static struct dadq *nd6_dad_find(struct ifaddr *); 82static void nd6_dad_starttimer(struct dadq *, int); 83static void nd6_dad_stoptimer(struct dadq *); 84static void nd6_dad_timer(struct dadq *); 85static void nd6_dad_ns_output(struct dadq *, struct ifaddr *); 86static void nd6_dad_ns_input(struct ifaddr *); 87static void nd6_dad_na_input(struct ifaddr *); 88static void nd6_na_output_fib(struct ifnet *, const struct in6_addr *, 89 const struct in6_addr *, u_long, int, struct sockaddr *, u_int); 90 91static VNET_DEFINE(int, dad_ignore_ns) = 0; /* ignore NS in DAD 92 - specwise incorrect */ 93static VNET_DEFINE(int, dad_maxtry) = 15; /* max # of *tries* to 94 transmit DAD packet */ 95#define V_dad_ignore_ns VNET(dad_ignore_ns) 96#define V_dad_maxtry VNET(dad_maxtry) 97 98/* 99 * Input a Neighbor Solicitation Message. 100 * 101 * Based on RFC 2461 102 * Based on RFC 2462 (duplicate address detection) 103 */ 104void 105nd6_ns_input(struct mbuf *m, int off, int icmp6len) 106{ 107 struct ifnet *ifp = m->m_pkthdr.rcvif; 108 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 109 struct nd_neighbor_solicit *nd_ns; 110 struct in6_addr saddr6 = ip6->ip6_src; 111 struct in6_addr daddr6 = ip6->ip6_dst; 112 struct in6_addr taddr6; 113 struct in6_addr myaddr6; 114 char *lladdr = NULL; 115 struct ifaddr *ifa = NULL; 116 int lladdrlen = 0; 117 int anycast = 0, proxy = 0, tentative = 0; 118 int tlladdr; 119 int rflag; 120 union nd_opts ndopts; 121 struct sockaddr_dl proxydl; 122 char ip6bufs[INET6_ADDRSTRLEN], ip6bufd[INET6_ADDRSTRLEN]; 123 124 rflag = (V_ip6_forwarding) ? ND_NA_FLAG_ROUTER : 0; 125 if (ND_IFINFO(ifp)->flags & ND6_IFF_ACCEPT_RTADV && V_ip6_norbit_raif) 126 rflag = 0; 127#ifndef PULLDOWN_TEST 128 IP6_EXTHDR_CHECK(m, off, icmp6len,); 129 nd_ns = (struct nd_neighbor_solicit *)((caddr_t)ip6 + off); 130#else 131 IP6_EXTHDR_GET(nd_ns, struct nd_neighbor_solicit *, m, off, icmp6len); 132 if (nd_ns == NULL) { 133 ICMP6STAT_INC(icp6s_tooshort); 134 return; 135 } 136#endif 137 ip6 = mtod(m, struct ip6_hdr *); /* adjust pointer for safety */ 138 taddr6 = nd_ns->nd_ns_target; 139 if (in6_setscope(&taddr6, ifp, NULL) != 0) 140 goto bad; 141 142 if (ip6->ip6_hlim != 255) { 143 nd6log((LOG_ERR, 144 "nd6_ns_input: invalid hlim (%d) from %s to %s on %s\n", 145 ip6->ip6_hlim, ip6_sprintf(ip6bufs, &ip6->ip6_src), 146 ip6_sprintf(ip6bufd, &ip6->ip6_dst), if_name(ifp))); 147 goto bad; 148 } 149 150 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) { 151 /* dst has to be a solicited node multicast address. */ 152 if (daddr6.s6_addr16[0] == IPV6_ADDR_INT16_MLL && 153 /* don't check ifindex portion */ 154 daddr6.s6_addr32[1] == 0 && 155 daddr6.s6_addr32[2] == IPV6_ADDR_INT32_ONE && 156 daddr6.s6_addr8[12] == 0xff) { 157 ; /* good */ 158 } else { 159 nd6log((LOG_INFO, "nd6_ns_input: bad DAD packet " 160 "(wrong ip6 dst)\n")); 161 goto bad; 162 } 163 } else if (!V_nd6_onlink_ns_rfc4861) { 164 struct sockaddr_in6 src_sa6; 165 166 /* 167 * According to recent IETF discussions, it is not a good idea 168 * to accept a NS from an address which would not be deemed 169 * to be a neighbor otherwise. This point is expected to be 170 * clarified in future revisions of the specification. 171 */ 172 bzero(&src_sa6, sizeof(src_sa6)); 173 src_sa6.sin6_family = AF_INET6; 174 src_sa6.sin6_len = sizeof(src_sa6); 175 src_sa6.sin6_addr = saddr6; 176 if (nd6_is_addr_neighbor(&src_sa6, ifp) == 0) { 177 nd6log((LOG_INFO, "nd6_ns_input: " 178 "NS packet from non-neighbor\n")); 179 goto bad; 180 } 181 } 182 183 if (IN6_IS_ADDR_MULTICAST(&taddr6)) { 184 nd6log((LOG_INFO, "nd6_ns_input: bad NS target (multicast)\n")); 185 goto bad; 186 } 187 188 icmp6len -= sizeof(*nd_ns); 189 nd6_option_init(nd_ns + 1, icmp6len, &ndopts); 190 if (nd6_options(&ndopts) < 0) { 191 nd6log((LOG_INFO, 192 "nd6_ns_input: invalid ND option, ignored\n")); 193 /* nd6_options have incremented stats */ 194 goto freeit; 195 } 196 197 if (ndopts.nd_opts_src_lladdr) { 198 lladdr = (char *)(ndopts.nd_opts_src_lladdr + 1); 199 lladdrlen = ndopts.nd_opts_src_lladdr->nd_opt_len << 3; 200 } 201 202 if (IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_src) && lladdr) { 203 nd6log((LOG_INFO, "nd6_ns_input: bad DAD packet " 204 "(link-layer address option)\n")); 205 goto bad; 206 } 207 208 /* 209 * Attaching target link-layer address to the NA? 210 * (RFC 2461 7.2.4) 211 * 212 * NS IP dst is unicast/anycast MUST NOT add 213 * NS IP dst is solicited-node multicast MUST add 214 * 215 * In implementation, we add target link-layer address by default. 216 * We do not add one in MUST NOT cases. 217 */ 218 if (!IN6_IS_ADDR_MULTICAST(&daddr6)) 219 tlladdr = 0; 220 else 221 tlladdr = 1; 222 223 /* 224 * Target address (taddr6) must be either: 225 * (1) Valid unicast/anycast address for my receiving interface, 226 * (2) Unicast address for which I'm offering proxy service, or 227 * (3) "tentative" address on which DAD is being performed. 228 */ 229 /* (1) and (3) check. */ 230 if (ifp->if_carp) 231 ifa = (*carp_iamatch6_p)(ifp, &taddr6); 232 else 233 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &taddr6); 234 235 /* (2) check. */ 236 if (ifa == NULL) { 237 struct route_in6 ro; 238 int need_proxy; 239 240 bzero(&ro, sizeof(ro)); 241 ro.ro_dst.sin6_len = sizeof(struct sockaddr_in6); 242 ro.ro_dst.sin6_family = AF_INET6; 243 ro.ro_dst.sin6_addr = taddr6; 244 245 /* Always use the default FIB. */ 246#ifdef RADIX_MPATH 247 rtalloc_mpath_fib((struct route *)&ro, RTF_ANNOUNCE, 248 RT_DEFAULT_FIB); 249#else 250 in6_rtalloc(&ro, RT_DEFAULT_FIB); 251#endif 252 need_proxy = (ro.ro_rt && 253 (ro.ro_rt->rt_flags & RTF_ANNOUNCE) != 0 && 254 ro.ro_rt->rt_gateway->sa_family == AF_LINK); 255 if (ro.ro_rt != NULL) { 256 if (need_proxy) 257 proxydl = *SDL(ro.ro_rt->rt_gateway); 258 RTFREE(ro.ro_rt); 259 } 260 if (need_proxy) { 261 /* 262 * proxy NDP for single entry 263 */ 264 ifa = (struct ifaddr *)in6ifa_ifpforlinklocal(ifp, 265 IN6_IFF_NOTREADY|IN6_IFF_ANYCAST); 266 if (ifa) 267 proxy = 1; 268 } 269 } 270 if (ifa == NULL) { 271 /* 272 * We've got an NS packet, and we don't have that adddress 273 * assigned for us. We MUST silently ignore it. 274 * See RFC2461 7.2.3. 275 */ 276 goto freeit; 277 } 278 myaddr6 = *IFA_IN6(ifa); 279 anycast = ((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_ANYCAST; 280 tentative = ((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_TENTATIVE; 281 if (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_DUPLICATED) 282 goto freeit; 283 284 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) { 285 nd6log((LOG_INFO, "nd6_ns_input: lladdrlen mismatch for %s " 286 "(if %d, NS packet %d)\n", 287 ip6_sprintf(ip6bufs, &taddr6), 288 ifp->if_addrlen, lladdrlen - 2)); 289 goto bad; 290 } 291 292 if (IN6_ARE_ADDR_EQUAL(&myaddr6, &saddr6)) { 293 nd6log((LOG_INFO, "nd6_ns_input: duplicate IP6 address %s\n", 294 ip6_sprintf(ip6bufs, &saddr6))); 295 goto freeit; 296 } 297 298 /* 299 * We have neighbor solicitation packet, with target address equals to 300 * one of my tentative address. 301 * 302 * src addr how to process? 303 * --- --- 304 * multicast of course, invalid (rejected in ip6_input) 305 * unicast somebody is doing address resolution -> ignore 306 * unspec dup address detection 307 * 308 * The processing is defined in RFC 2462. 309 */ 310 if (tentative) { 311 /* 312 * If source address is unspecified address, it is for 313 * duplicate address detection. 314 * 315 * If not, the packet is for addess resolution; 316 * silently ignore it. 317 */ 318 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) 319 nd6_dad_ns_input(ifa); 320 321 goto freeit; 322 } 323 324 /* 325 * If the source address is unspecified address, entries must not 326 * be created or updated. 327 * It looks that sender is performing DAD. Output NA toward 328 * all-node multicast address, to tell the sender that I'm using 329 * the address. 330 * S bit ("solicited") must be zero. 331 */ 332 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) { 333 struct in6_addr in6_all; 334 335 in6_all = in6addr_linklocal_allnodes; 336 if (in6_setscope(&in6_all, ifp, NULL) != 0) 337 goto bad; 338 nd6_na_output_fib(ifp, &in6_all, &taddr6, 339 ((anycast || proxy || !tlladdr) ? 0 : ND_NA_FLAG_OVERRIDE) | 340 rflag, tlladdr, proxy ? (struct sockaddr *)&proxydl : NULL, 341 M_GETFIB(m)); 342 goto freeit; 343 } 344 345 nd6_cache_lladdr(ifp, &saddr6, lladdr, lladdrlen, 346 ND_NEIGHBOR_SOLICIT, 0); 347 348 nd6_na_output_fib(ifp, &saddr6, &taddr6, 349 ((anycast || proxy || !tlladdr) ? 0 : ND_NA_FLAG_OVERRIDE) | 350 rflag | ND_NA_FLAG_SOLICITED, tlladdr, 351 proxy ? (struct sockaddr *)&proxydl : NULL, M_GETFIB(m)); 352 freeit: 353 if (ifa != NULL) 354 ifa_free(ifa); 355 m_freem(m); 356 return; 357 358 bad: 359 nd6log((LOG_ERR, "nd6_ns_input: src=%s\n", 360 ip6_sprintf(ip6bufs, &saddr6))); 361 nd6log((LOG_ERR, "nd6_ns_input: dst=%s\n", 362 ip6_sprintf(ip6bufs, &daddr6))); 363 nd6log((LOG_ERR, "nd6_ns_input: tgt=%s\n", 364 ip6_sprintf(ip6bufs, &taddr6))); 365 ICMP6STAT_INC(icp6s_badns); 366 if (ifa != NULL) 367 ifa_free(ifa); 368 m_freem(m); 369} 370 371/* 372 * Output a Neighbor Solicitation Message. Caller specifies: 373 * - ICMP6 header source IP6 address 374 * - ND6 header target IP6 address 375 * - ND6 header source datalink address 376 * 377 * Based on RFC 2461 378 * Based on RFC 2462 (duplicate address detection) 379 * 380 * ln - for source address determination 381 * dad - duplicate address detection 382 */ 383void 384nd6_ns_output(struct ifnet *ifp, const struct in6_addr *daddr6, 385 const struct in6_addr *taddr6, struct llentry *ln, int dad) 386{ 387 struct mbuf *m; 388 struct m_tag *mtag; 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 KASSERT(max_linkhdr + maxlen <= MCLBYTES, ( 404 "%s: max_linkhdr + maxlen > MCLBYTES (%d + %d > %d)", 405 __func__, max_linkhdr, maxlen, MCLBYTES)); 406 407 if (max_linkhdr + maxlen > MHLEN) 408 m = m_getcl(M_NOWAIT, MT_DATA, M_PKTHDR); 409 else 410 m = m_gethdr(M_NOWAIT, MT_DATA); 411 if (m == NULL) 412 return; 413 414 bzero(&ro, sizeof(ro)); 415 416 if (daddr6 == NULL || IN6_IS_ADDR_MULTICAST(daddr6)) { 417 m->m_flags |= M_MCAST; 418 im6o.im6o_multicast_ifp = ifp; 419 im6o.im6o_multicast_hlim = 255; 420 im6o.im6o_multicast_loop = 0; 421 } 422 423 icmp6len = sizeof(*nd_ns); 424 m->m_pkthdr.len = m->m_len = sizeof(*ip6) + icmp6len; 425 m->m_data += max_linkhdr; /* or MH_ALIGN() equivalent? */ 426 427 /* fill neighbor solicitation packet */ 428 ip6 = mtod(m, struct ip6_hdr *); 429 ip6->ip6_flow = 0; 430 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 431 ip6->ip6_vfc |= IPV6_VERSION; 432 /* ip6->ip6_plen will be set later */ 433 ip6->ip6_nxt = IPPROTO_ICMPV6; 434 ip6->ip6_hlim = 255; 435 if (daddr6) 436 ip6->ip6_dst = *daddr6; 437 else { 438 ip6->ip6_dst.s6_addr16[0] = IPV6_ADDR_INT16_MLL; 439 ip6->ip6_dst.s6_addr16[1] = 0; 440 ip6->ip6_dst.s6_addr32[1] = 0; 441 ip6->ip6_dst.s6_addr32[2] = IPV6_ADDR_INT32_ONE; 442 ip6->ip6_dst.s6_addr32[3] = taddr6->s6_addr32[3]; 443 ip6->ip6_dst.s6_addr8[12] = 0xff; 444 if (in6_setscope(&ip6->ip6_dst, ifp, NULL) != 0) 445 goto bad; 446 } 447 if (!dad) { 448 struct ifaddr *ifa; 449 450 /* 451 * RFC2461 7.2.2: 452 * "If the source address of the packet prompting the 453 * solicitation is the same as one of the addresses assigned 454 * to the outgoing interface, that address SHOULD be placed 455 * in the IP Source Address of the outgoing solicitation. 456 * Otherwise, any one of the addresses assigned to the 457 * interface should be used." 458 * 459 * We use the source address for the prompting packet 460 * (saddr6), if: 461 * - saddr6 is given from the caller (by giving "ln"), and 462 * - saddr6 belongs to the outgoing interface. 463 * Otherwise, we perform the source address selection as usual. 464 */ 465 struct in6_addr *hsrc; 466 467 hsrc = NULL; 468 if (ln != NULL) { 469 LLE_RLOCK(ln); 470 if (ln->la_hold != NULL) { 471 struct ip6_hdr *hip6; /* hold ip6 */ 472 473 /* 474 * assuming every packet in la_hold has the same IP 475 * header 476 */ 477 hip6 = mtod(ln->la_hold, struct ip6_hdr *); 478 /* XXX pullup? */ 479 if (sizeof(*hip6) < ln->la_hold->m_len) { 480 ip6->ip6_src = hip6->ip6_src; 481 hsrc = &hip6->ip6_src; 482 } 483 } 484 LLE_RUNLOCK(ln); 485 } 486 if (hsrc && (ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, 487 hsrc)) != NULL) { 488 /* ip6_src set already. */ 489 ifa_free(ifa); 490 } else { 491 int error; 492 struct sockaddr_in6 dst_sa; 493 struct in6_addr src_in; 494 struct ifnet *oifp; 495 496 bzero(&dst_sa, sizeof(dst_sa)); 497 dst_sa.sin6_family = AF_INET6; 498 dst_sa.sin6_len = sizeof(dst_sa); 499 dst_sa.sin6_addr = ip6->ip6_dst; 500 501 oifp = ifp; 502 error = in6_selectsrc(&dst_sa, NULL, 503 NULL, &ro, NULL, &oifp, &src_in); 504 if (error) { 505 char ip6buf[INET6_ADDRSTRLEN]; 506 nd6log((LOG_DEBUG, 507 "nd6_ns_output: source can't be " 508 "determined: dst=%s, error=%d\n", 509 ip6_sprintf(ip6buf, &dst_sa.sin6_addr), 510 error)); 511 goto bad; 512 } 513 ip6->ip6_src = src_in; 514 } 515 } else { 516 /* 517 * Source address for DAD packet must always be IPv6 518 * unspecified address. (0::0) 519 * We actually don't have to 0-clear the address (we did it 520 * above), but we do so here explicitly to make the intention 521 * clearer. 522 */ 523 bzero(&ip6->ip6_src, sizeof(ip6->ip6_src)); 524 } 525 nd_ns = (struct nd_neighbor_solicit *)(ip6 + 1); 526 nd_ns->nd_ns_type = ND_NEIGHBOR_SOLICIT; 527 nd_ns->nd_ns_code = 0; 528 nd_ns->nd_ns_reserved = 0; 529 nd_ns->nd_ns_target = *taddr6; 530 in6_clearscope(&nd_ns->nd_ns_target); /* XXX */ 531 532 /* 533 * Add source link-layer address option. 534 * 535 * spec implementation 536 * --- --- 537 * DAD packet MUST NOT do not add the option 538 * there's no link layer address: 539 * impossible do not add the option 540 * there's link layer address: 541 * Multicast NS MUST add one add the option 542 * Unicast NS SHOULD add one add the option 543 */ 544 if (!dad && (mac = nd6_ifptomac(ifp))) { 545 int optlen = sizeof(struct nd_opt_hdr) + ifp->if_addrlen; 546 struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)(nd_ns + 1); 547 /* 8 byte alignments... */ 548 optlen = (optlen + 7) & ~7; 549 550 m->m_pkthdr.len += optlen; 551 m->m_len += optlen; 552 icmp6len += optlen; 553 bzero((caddr_t)nd_opt, optlen); 554 nd_opt->nd_opt_type = ND_OPT_SOURCE_LINKADDR; 555 nd_opt->nd_opt_len = optlen >> 3; 556 bcopy(mac, (caddr_t)(nd_opt + 1), ifp->if_addrlen); 557 } 558 559 ip6->ip6_plen = htons((u_short)icmp6len); 560 nd_ns->nd_ns_cksum = 0; 561 nd_ns->nd_ns_cksum = 562 in6_cksum(m, IPPROTO_ICMPV6, sizeof(*ip6), icmp6len); 563 564 if (send_sendso_input_hook != NULL) { 565 mtag = m_tag_get(PACKET_TAG_ND_OUTGOING, 566 sizeof(unsigned short), M_NOWAIT); 567 if (mtag == NULL) 568 goto bad; 569 *(unsigned short *)(mtag + 1) = nd_ns->nd_ns_type; 570 m_tag_prepend(m, mtag); 571 } 572 573 ip6_output(m, NULL, &ro, dad ? IPV6_UNSPECSRC : 0, &im6o, NULL, NULL); 574 icmp6_ifstat_inc(ifp, ifs6_out_msg); 575 icmp6_ifstat_inc(ifp, ifs6_out_neighborsolicit); 576 ICMP6STAT_INC(icp6s_outhist[ND_NEIGHBOR_SOLICIT]); 577 578 /* We don't cache this route. */ 579 RO_RTFREE(&ro); 580 581 return; 582 583 bad: 584 if (ro.ro_rt) { 585 RTFREE(ro.ro_rt); 586 } 587 m_freem(m); 588 return; 589} 590 591/* 592 * Neighbor advertisement input handling. 593 * 594 * Based on RFC 2461 595 * Based on RFC 2462 (duplicate address detection) 596 * 597 * the following items are not implemented yet: 598 * - proxy advertisement delay rule (RFC2461 7.2.8, last paragraph, SHOULD) 599 * - anycast advertisement delay rule (RFC2461 7.2.7, SHOULD) 600 */ 601void 602nd6_na_input(struct mbuf *m, int off, int icmp6len) 603{ 604 struct ifnet *ifp = m->m_pkthdr.rcvif; 605 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 606 struct nd_neighbor_advert *nd_na; 607 struct in6_addr daddr6 = ip6->ip6_dst; 608 struct in6_addr taddr6; 609 int flags; 610 int is_router; 611 int is_solicited; 612 int is_override; 613 char *lladdr = NULL; 614 int lladdrlen = 0; 615 int checklink = 0; 616 struct ifaddr *ifa; 617 struct llentry *ln = NULL; 618 union nd_opts ndopts; 619 struct mbuf *chain = NULL; 620 struct m_tag *mtag; 621 struct sockaddr_in6 sin6; 622 char ip6bufs[INET6_ADDRSTRLEN], ip6bufd[INET6_ADDRSTRLEN]; 623 624 if (ip6->ip6_hlim != 255) { 625 nd6log((LOG_ERR, 626 "nd6_na_input: invalid hlim (%d) from %s to %s on %s\n", 627 ip6->ip6_hlim, ip6_sprintf(ip6bufs, &ip6->ip6_src), 628 ip6_sprintf(ip6bufd, &ip6->ip6_dst), if_name(ifp))); 629 goto bad; 630 } 631 632#ifndef PULLDOWN_TEST 633 IP6_EXTHDR_CHECK(m, off, icmp6len,); 634 nd_na = (struct nd_neighbor_advert *)((caddr_t)ip6 + off); 635#else 636 IP6_EXTHDR_GET(nd_na, struct nd_neighbor_advert *, m, off, icmp6len); 637 if (nd_na == NULL) { 638 ICMP6STAT_INC(icp6s_tooshort); 639 return; 640 } 641#endif 642 643 flags = nd_na->nd_na_flags_reserved; 644 is_router = ((flags & ND_NA_FLAG_ROUTER) != 0); 645 is_solicited = ((flags & ND_NA_FLAG_SOLICITED) != 0); 646 is_override = ((flags & ND_NA_FLAG_OVERRIDE) != 0); 647 648 taddr6 = nd_na->nd_na_target; 649 if (in6_setscope(&taddr6, ifp, NULL)) 650 goto bad; /* XXX: impossible */ 651 652 if (IN6_IS_ADDR_MULTICAST(&taddr6)) { 653 nd6log((LOG_ERR, 654 "nd6_na_input: invalid target address %s\n", 655 ip6_sprintf(ip6bufs, &taddr6))); 656 goto bad; 657 } 658 if (IN6_IS_ADDR_MULTICAST(&daddr6)) 659 if (is_solicited) { 660 nd6log((LOG_ERR, 661 "nd6_na_input: a solicited adv is multicasted\n")); 662 goto bad; 663 } 664 665 icmp6len -= sizeof(*nd_na); 666 nd6_option_init(nd_na + 1, icmp6len, &ndopts); 667 if (nd6_options(&ndopts) < 0) { 668 nd6log((LOG_INFO, 669 "nd6_na_input: invalid ND option, ignored\n")); 670 /* nd6_options have incremented stats */ 671 goto freeit; 672 } 673 674 if (ndopts.nd_opts_tgt_lladdr) { 675 lladdr = (char *)(ndopts.nd_opts_tgt_lladdr + 1); 676 lladdrlen = ndopts.nd_opts_tgt_lladdr->nd_opt_len << 3; 677 } 678 679 /* 680 * This effectively disables the DAD check on a non-master CARP 681 * address. 682 */ 683 if (ifp->if_carp) 684 ifa = (*carp_iamatch6_p)(ifp, &taddr6); 685 else 686 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &taddr6); 687 688 /* 689 * Target address matches one of my interface address. 690 * 691 * If my address is tentative, this means that there's somebody 692 * already using the same address as mine. This indicates DAD failure. 693 * This is defined in RFC 2462. 694 * 695 * Otherwise, process as defined in RFC 2461. 696 */ 697 if (ifa 698 && (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_TENTATIVE)) { 699 nd6_dad_na_input(ifa); 700 ifa_free(ifa); 701 goto freeit; 702 } 703 704 /* Just for safety, maybe unnecessary. */ 705 if (ifa) { 706 ifa_free(ifa); 707 log(LOG_ERR, 708 "nd6_na_input: duplicate IP6 address %s\n", 709 ip6_sprintf(ip6bufs, &taddr6)); 710 goto freeit; 711 } 712 713 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) { 714 nd6log((LOG_INFO, "nd6_na_input: lladdrlen mismatch for %s " 715 "(if %d, NA packet %d)\n", ip6_sprintf(ip6bufs, &taddr6), 716 ifp->if_addrlen, lladdrlen - 2)); 717 goto bad; 718 } 719 720 /* 721 * If no neighbor cache entry is found, NA SHOULD silently be 722 * discarded. 723 */ 724 IF_AFDATA_RLOCK(ifp); 725 ln = nd6_lookup(&taddr6, LLE_EXCLUSIVE, ifp); 726 IF_AFDATA_RUNLOCK(ifp); 727 if (ln == NULL) { 728 goto freeit; 729 } 730 731 if (ln->ln_state == ND6_LLINFO_INCOMPLETE) { 732 /* 733 * If the link-layer has address, and no lladdr option came, 734 * discard the packet. 735 */ 736 if (ifp->if_addrlen && lladdr == NULL) { 737 goto freeit; 738 } 739 740 /* 741 * Record link-layer address, and update the state. 742 */ 743 bcopy(lladdr, &ln->ll_addr, ifp->if_addrlen); 744 ln->la_flags |= LLE_VALID; 745 EVENTHANDLER_INVOKE(lle_event, ln, LLENTRY_RESOLVED); 746 if (is_solicited) { 747 ln->ln_state = ND6_LLINFO_REACHABLE; 748 ln->ln_byhint = 0; 749 if (!ND6_LLINFO_PERMANENT(ln)) { 750 nd6_llinfo_settimer_locked(ln, 751 (long)ND_IFINFO(ln->lle_tbl->llt_ifp)->reachable * hz); 752 } 753 } else { 754 ln->ln_state = ND6_LLINFO_STALE; 755 nd6_llinfo_settimer_locked(ln, (long)V_nd6_gctimer * hz); 756 } 757 if ((ln->ln_router = is_router) != 0) { 758 /* 759 * This means a router's state has changed from 760 * non-reachable to probably reachable, and might 761 * affect the status of associated prefixes.. 762 */ 763 checklink = 1; 764 } 765 } else { 766 int llchange; 767 768 /* 769 * Check if the link-layer address has changed or not. 770 */ 771 if (lladdr == NULL) 772 llchange = 0; 773 else { 774 if (ln->la_flags & LLE_VALID) { 775 if (bcmp(lladdr, &ln->ll_addr, ifp->if_addrlen)) 776 llchange = 1; 777 else 778 llchange = 0; 779 } else 780 llchange = 1; 781 } 782 783 /* 784 * This is VERY complex. Look at it with care. 785 * 786 * override solicit lladdr llchange action 787 * (L: record lladdr) 788 * 789 * 0 0 n -- (2c) 790 * 0 0 y n (2b) L 791 * 0 0 y y (1) REACHABLE->STALE 792 * 0 1 n -- (2c) *->REACHABLE 793 * 0 1 y n (2b) L *->REACHABLE 794 * 0 1 y y (1) REACHABLE->STALE 795 * 1 0 n -- (2a) 796 * 1 0 y n (2a) L 797 * 1 0 y y (2a) L *->STALE 798 * 1 1 n -- (2a) *->REACHABLE 799 * 1 1 y n (2a) L *->REACHABLE 800 * 1 1 y y (2a) L *->REACHABLE 801 */ 802 if (!is_override && (lladdr != NULL && llchange)) { /* (1) */ 803 /* 804 * If state is REACHABLE, make it STALE. 805 * no other updates should be done. 806 */ 807 if (ln->ln_state == ND6_LLINFO_REACHABLE) { 808 ln->ln_state = ND6_LLINFO_STALE; 809 nd6_llinfo_settimer_locked(ln, (long)V_nd6_gctimer * hz); 810 } 811 goto freeit; 812 } else if (is_override /* (2a) */ 813 || (!is_override && (lladdr != NULL && !llchange)) /* (2b) */ 814 || lladdr == NULL) { /* (2c) */ 815 /* 816 * Update link-local address, if any. 817 */ 818 if (lladdr != NULL) { 819 bcopy(lladdr, &ln->ll_addr, ifp->if_addrlen); 820 ln->la_flags |= LLE_VALID; 821 EVENTHANDLER_INVOKE(lle_event, ln, 822 LLENTRY_RESOLVED); 823 } 824 825 /* 826 * If solicited, make the state REACHABLE. 827 * If not solicited and the link-layer address was 828 * changed, make it STALE. 829 */ 830 if (is_solicited) { 831 ln->ln_state = ND6_LLINFO_REACHABLE; 832 ln->ln_byhint = 0; 833 if (!ND6_LLINFO_PERMANENT(ln)) { 834 nd6_llinfo_settimer_locked(ln, 835 (long)ND_IFINFO(ifp)->reachable * hz); 836 } 837 } else { 838 if (lladdr != NULL && llchange) { 839 ln->ln_state = ND6_LLINFO_STALE; 840 nd6_llinfo_settimer_locked(ln, 841 (long)V_nd6_gctimer * hz); 842 } 843 } 844 } 845 846 if (ln->ln_router && !is_router) { 847 /* 848 * The peer dropped the router flag. 849 * Remove the sender from the Default Router List and 850 * update the Destination Cache entries. 851 */ 852 struct nd_defrouter *dr; 853 struct in6_addr *in6; 854 855 in6 = &L3_ADDR_SIN6(ln)->sin6_addr; 856 857 /* 858 * Lock to protect the default router list. 859 * XXX: this might be unnecessary, since this function 860 * is only called under the network software interrupt 861 * context. However, we keep it just for safety. 862 */ 863 dr = defrouter_lookup(in6, ln->lle_tbl->llt_ifp); 864 if (dr) 865 defrtrlist_del(dr); 866 else if (ND_IFINFO(ln->lle_tbl->llt_ifp)->flags & 867 ND6_IFF_ACCEPT_RTADV) { 868 /* 869 * Even if the neighbor is not in the default 870 * router list, the neighbor may be used 871 * as a next hop for some destinations 872 * (e.g. redirect case). So we must 873 * call rt6_flush explicitly. 874 */ 875 rt6_flush(&ip6->ip6_src, ifp); 876 } 877 } 878 ln->ln_router = is_router; 879 } 880 /* XXX - QL 881 * Does this matter? 882 * rt->rt_flags &= ~RTF_REJECT; 883 */ 884 ln->la_asked = 0; 885 if (ln->la_hold) { 886 struct mbuf *m_hold, *m_hold_next; 887 888 /* 889 * reset the la_hold in advance, to explicitly 890 * prevent a la_hold lookup in nd6_output() 891 * (wouldn't happen, though...) 892 */ 893 for (m_hold = ln->la_hold, ln->la_hold = NULL; 894 m_hold; m_hold = m_hold_next) { 895 m_hold_next = m_hold->m_nextpkt; 896 m_hold->m_nextpkt = NULL; 897 /* 898 * we assume ifp is not a loopback here, so just set 899 * the 2nd argument as the 1st one. 900 */ 901 902 if (send_sendso_input_hook != NULL) { 903 mtag = m_tag_get(PACKET_TAG_ND_OUTGOING, 904 sizeof(unsigned short), M_NOWAIT); 905 if (mtag == NULL) 906 goto bad; 907 m_tag_prepend(m, mtag); 908 } 909 910 nd6_output_lle(ifp, ifp, m_hold, L3_ADDR_SIN6(ln), NULL, ln, &chain); 911 } 912 } 913 freeit: 914 if (ln != NULL) { 915 if (chain) 916 memcpy(&sin6, L3_ADDR_SIN6(ln), sizeof(sin6)); 917 LLE_WUNLOCK(ln); 918 919 if (chain) 920 nd6_output_flush(ifp, ifp, chain, &sin6, NULL); 921 } 922 if (checklink) 923 pfxlist_onlink_check(); 924 925 m_freem(m); 926 return; 927 928 bad: 929 if (ln != NULL) 930 LLE_WUNLOCK(ln); 931 932 ICMP6STAT_INC(icp6s_badna); 933 m_freem(m); 934} 935 936/* 937 * Neighbor advertisement output handling. 938 * 939 * Based on RFC 2461 940 * 941 * the following items are not implemented yet: 942 * - proxy advertisement delay rule (RFC2461 7.2.8, last paragraph, SHOULD) 943 * - anycast advertisement delay rule (RFC2461 7.2.7, SHOULD) 944 * 945 * tlladdr - 1 if include target link-layer address 946 * sdl0 - sockaddr_dl (= proxy NA) or NULL 947 */ 948static void 949nd6_na_output_fib(struct ifnet *ifp, const struct in6_addr *daddr6_0, 950 const struct in6_addr *taddr6, u_long flags, int tlladdr, 951 struct sockaddr *sdl0, u_int fibnum) 952{ 953 struct mbuf *m; 954 struct m_tag *mtag; 955 struct ifnet *oifp; 956 struct ip6_hdr *ip6; 957 struct nd_neighbor_advert *nd_na; 958 struct ip6_moptions im6o; 959 struct in6_addr src, daddr6; 960 struct sockaddr_in6 dst_sa; 961 int icmp6len, maxlen, error; 962 caddr_t mac = NULL; 963 struct route_in6 ro; 964 965 bzero(&ro, sizeof(ro)); 966 967 daddr6 = *daddr6_0; /* make a local copy for modification */ 968 969 /* estimate the size of message */ 970 maxlen = sizeof(*ip6) + sizeof(*nd_na); 971 maxlen += (sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7; 972 KASSERT(max_linkhdr + maxlen <= MCLBYTES, ( 973 "%s: max_linkhdr + maxlen > MCLBYTES (%d + %d > %d)", 974 __func__, max_linkhdr, maxlen, MCLBYTES)); 975 976 if (max_linkhdr + maxlen > MHLEN) 977 m = m_getcl(M_NOWAIT, MT_DATA, M_PKTHDR); 978 else 979 m = m_gethdr(M_NOWAIT, MT_DATA); 980 if (m == NULL) 981 return; 982 M_SETFIB(m, fibnum); 983 984 if (IN6_IS_ADDR_MULTICAST(&daddr6)) { 985 m->m_flags |= M_MCAST; 986 im6o.im6o_multicast_ifp = ifp; 987 im6o.im6o_multicast_hlim = 255; 988 im6o.im6o_multicast_loop = 0; 989 } 990 991 icmp6len = sizeof(*nd_na); 992 m->m_pkthdr.len = m->m_len = sizeof(struct ip6_hdr) + icmp6len; 993 m->m_data += max_linkhdr; /* or MH_ALIGN() equivalent? */ 994 995 /* fill neighbor advertisement packet */ 996 ip6 = mtod(m, struct ip6_hdr *); 997 ip6->ip6_flow = 0; 998 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 999 ip6->ip6_vfc |= IPV6_VERSION; 1000 ip6->ip6_nxt = IPPROTO_ICMPV6; 1001 ip6->ip6_hlim = 255; 1002 if (IN6_IS_ADDR_UNSPECIFIED(&daddr6)) { 1003 /* reply to DAD */ 1004 daddr6.s6_addr16[0] = IPV6_ADDR_INT16_MLL; 1005 daddr6.s6_addr16[1] = 0; 1006 daddr6.s6_addr32[1] = 0; 1007 daddr6.s6_addr32[2] = 0; 1008 daddr6.s6_addr32[3] = IPV6_ADDR_INT32_ONE; 1009 if (in6_setscope(&daddr6, ifp, NULL)) 1010 goto bad; 1011 1012 flags &= ~ND_NA_FLAG_SOLICITED; 1013 } 1014 ip6->ip6_dst = daddr6; 1015 bzero(&dst_sa, sizeof(struct sockaddr_in6)); 1016 dst_sa.sin6_family = AF_INET6; 1017 dst_sa.sin6_len = sizeof(struct sockaddr_in6); 1018 dst_sa.sin6_addr = daddr6; 1019 1020 /* 1021 * Select a source whose scope is the same as that of the dest. 1022 */ 1023 bcopy(&dst_sa, &ro.ro_dst, sizeof(dst_sa)); 1024 oifp = ifp; 1025 error = in6_selectsrc(&dst_sa, NULL, NULL, &ro, NULL, &oifp, &src); 1026 if (error) { 1027 char ip6buf[INET6_ADDRSTRLEN]; 1028 nd6log((LOG_DEBUG, "nd6_na_output: source can't be " 1029 "determined: dst=%s, error=%d\n", 1030 ip6_sprintf(ip6buf, &dst_sa.sin6_addr), error)); 1031 goto bad; 1032 } 1033 ip6->ip6_src = src; 1034 nd_na = (struct nd_neighbor_advert *)(ip6 + 1); 1035 nd_na->nd_na_type = ND_NEIGHBOR_ADVERT; 1036 nd_na->nd_na_code = 0; 1037 nd_na->nd_na_target = *taddr6; 1038 in6_clearscope(&nd_na->nd_na_target); /* XXX */ 1039 1040 /* 1041 * "tlladdr" indicates NS's condition for adding tlladdr or not. 1042 * see nd6_ns_input() for details. 1043 * Basically, if NS packet is sent to unicast/anycast addr, 1044 * target lladdr option SHOULD NOT be included. 1045 */ 1046 if (tlladdr) { 1047 /* 1048 * sdl0 != NULL indicates proxy NA. If we do proxy, use 1049 * lladdr in sdl0. If we are not proxying (sending NA for 1050 * my address) use lladdr configured for the interface. 1051 */ 1052 if (sdl0 == NULL) { 1053 if (ifp->if_carp) 1054 mac = (*carp_macmatch6_p)(ifp, m, taddr6); 1055 if (mac == NULL) 1056 mac = nd6_ifptomac(ifp); 1057 } else if (sdl0->sa_family == AF_LINK) { 1058 struct sockaddr_dl *sdl; 1059 sdl = (struct sockaddr_dl *)sdl0; 1060 if (sdl->sdl_alen == ifp->if_addrlen) 1061 mac = LLADDR(sdl); 1062 } 1063 } 1064 if (tlladdr && mac) { 1065 int optlen = sizeof(struct nd_opt_hdr) + ifp->if_addrlen; 1066 struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)(nd_na + 1); 1067 1068 /* roundup to 8 bytes alignment! */ 1069 optlen = (optlen + 7) & ~7; 1070 1071 m->m_pkthdr.len += optlen; 1072 m->m_len += optlen; 1073 icmp6len += optlen; 1074 bzero((caddr_t)nd_opt, optlen); 1075 nd_opt->nd_opt_type = ND_OPT_TARGET_LINKADDR; 1076 nd_opt->nd_opt_len = optlen >> 3; 1077 bcopy(mac, (caddr_t)(nd_opt + 1), ifp->if_addrlen); 1078 } else 1079 flags &= ~ND_NA_FLAG_OVERRIDE; 1080 1081 ip6->ip6_plen = htons((u_short)icmp6len); 1082 nd_na->nd_na_flags_reserved = flags; 1083 nd_na->nd_na_cksum = 0; 1084 nd_na->nd_na_cksum = 1085 in6_cksum(m, IPPROTO_ICMPV6, sizeof(struct ip6_hdr), icmp6len); 1086 1087 if (send_sendso_input_hook != NULL) { 1088 mtag = m_tag_get(PACKET_TAG_ND_OUTGOING, 1089 sizeof(unsigned short), M_NOWAIT); 1090 if (mtag == NULL) 1091 goto bad; 1092 *(unsigned short *)(mtag + 1) = nd_na->nd_na_type; 1093 m_tag_prepend(m, mtag); 1094 } 1095 1096 ip6_output(m, NULL, &ro, 0, &im6o, NULL, NULL); 1097 icmp6_ifstat_inc(ifp, ifs6_out_msg); 1098 icmp6_ifstat_inc(ifp, ifs6_out_neighboradvert); 1099 ICMP6STAT_INC(icp6s_outhist[ND_NEIGHBOR_ADVERT]); 1100 1101 /* We don't cache this route. */ 1102 RO_RTFREE(&ro); 1103 1104 return; 1105 1106 bad: 1107 if (ro.ro_rt) { 1108 RTFREE(ro.ro_rt); 1109 } 1110 m_freem(m); 1111 return; 1112} 1113 1114#ifndef BURN_BRIDGES 1115void 1116nd6_na_output(struct ifnet *ifp, const struct in6_addr *daddr6_0, 1117 const struct in6_addr *taddr6, u_long flags, int tlladdr, 1118 struct sockaddr *sdl0) 1119{ 1120 1121 nd6_na_output_fib(ifp, daddr6_0, taddr6, flags, tlladdr, sdl0, 1122 RT_DEFAULT_FIB); 1123} 1124#endif 1125 1126caddr_t 1127nd6_ifptomac(struct ifnet *ifp) 1128{ 1129 switch (ifp->if_type) { 1130 case IFT_ARCNET: 1131 case IFT_ETHER: 1132 case IFT_FDDI: 1133 case IFT_IEEE1394: 1134#ifdef IFT_L2VLAN 1135 case IFT_L2VLAN: 1136#endif 1137#ifdef IFT_IEEE80211 1138 case IFT_IEEE80211: 1139#endif 1140 case IFT_INFINIBAND: 1141 case IFT_BRIDGE: 1142 case IFT_ISO88025: 1143 return IF_LLADDR(ifp); 1144 default: 1145 return NULL; 1146 } 1147} 1148 1149struct dadq { 1150 TAILQ_ENTRY(dadq) dad_list; 1151 struct ifaddr *dad_ifa; 1152 int dad_count; /* max NS to send */ 1153 int dad_ns_tcount; /* # of trials to send NS */ 1154 int dad_ns_ocount; /* NS sent so far */ 1155 int dad_ns_icount; 1156 int dad_na_icount; 1157 struct callout dad_timer_ch; 1158 struct vnet *dad_vnet; 1159}; 1160 1161static VNET_DEFINE(TAILQ_HEAD(, dadq), dadq); 1162static VNET_DEFINE(struct rwlock, dad_rwlock); 1163#define V_dadq VNET(dadq) 1164#define V_dad_rwlock VNET(dad_rwlock) 1165 1166#define DADQ_LOCK_INIT() rw_init(&V_dad_rwlock, "nd6 DAD queue") 1167#define DADQ_LOCK_DESTROY() rw_destroy(&V_dad_rwlock) 1168#define DADQ_LOCK_INITIALIZED() rw_initialized(&V_dad_rwlock) 1169#define DADQ_RLOCK() rw_rlock(&V_dad_rwlock) 1170#define DADQ_RUNLOCK() rw_runlock(&V_dad_rwlock) 1171#define DADQ_WLOCK() rw_wlock(&V_dad_rwlock) 1172#define DADQ_WUNLOCK() rw_wunlock(&V_dad_rwlock) 1173 1174static struct dadq * 1175nd6_dad_find(struct ifaddr *ifa) 1176{ 1177 struct dadq *dp; 1178 1179 DADQ_RLOCK(); 1180 TAILQ_FOREACH(dp, &V_dadq, dad_list) 1181 if (dp->dad_ifa == ifa) 1182 break; 1183 DADQ_RUNLOCK(); 1184 1185 return (dp); 1186} 1187 1188static void 1189nd6_dad_starttimer(struct dadq *dp, int ticks) 1190{ 1191 1192 callout_reset(&dp->dad_timer_ch, ticks, 1193 (void (*)(void *))nd6_dad_timer, (void *)dp); 1194} 1195 1196static void 1197nd6_dad_stoptimer(struct dadq *dp) 1198{ 1199 1200 callout_stop(&dp->dad_timer_ch); 1201} 1202 1203/* 1204 * Start Duplicate Address Detection (DAD) for specified interface address. 1205 */ 1206void 1207nd6_dad_start(struct ifaddr *ifa, int delay) 1208{ 1209 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1210 struct dadq *dp; 1211 char ip6buf[INET6_ADDRSTRLEN]; 1212 1213 if (DADQ_LOCK_INITIALIZED() == 0) { 1214 DADQ_LOCK_INIT(); 1215 TAILQ_INIT(&V_dadq); 1216 } 1217 1218 /* 1219 * If we don't need DAD, don't do it. 1220 * There are several cases: 1221 * - DAD is disabled (ip6_dad_count == 0) 1222 * - the interface address is anycast 1223 */ 1224 if (!(ia->ia6_flags & IN6_IFF_TENTATIVE)) { 1225 log(LOG_DEBUG, 1226 "nd6_dad_start: called with non-tentative address " 1227 "%s(%s)\n", 1228 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr), 1229 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1230 return; 1231 } 1232 if (ia->ia6_flags & IN6_IFF_ANYCAST) { 1233 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1234 return; 1235 } 1236 if (!V_ip6_dad_count) { 1237 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1238 return; 1239 } 1240 if (ifa->ifa_ifp == NULL) 1241 panic("nd6_dad_start: ifa->ifa_ifp == NULL"); 1242 if (!(ifa->ifa_ifp->if_flags & IFF_UP)) { 1243 return; 1244 } 1245 if (ND_IFINFO(ifa->ifa_ifp)->flags & ND6_IFF_IFDISABLED) 1246 return; 1247 if (nd6_dad_find(ifa) != NULL) { 1248 /* DAD already in progress */ 1249 return; 1250 } 1251 1252 dp = malloc(sizeof(*dp), M_IP6NDP, M_NOWAIT); 1253 if (dp == NULL) { 1254 log(LOG_ERR, "nd6_dad_start: memory allocation failed for " 1255 "%s(%s)\n", 1256 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr), 1257 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1258 return; 1259 } 1260 bzero(dp, sizeof(*dp)); 1261 callout_init(&dp->dad_timer_ch, 0); 1262#ifdef VIMAGE 1263 dp->dad_vnet = curvnet; 1264#endif 1265 DADQ_WLOCK(); 1266 TAILQ_INSERT_TAIL(&V_dadq, (struct dadq *)dp, dad_list); 1267 DADQ_WUNLOCK(); 1268 1269 nd6log((LOG_DEBUG, "%s: starting DAD for %s\n", if_name(ifa->ifa_ifp), 1270 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr))); 1271 1272 /* 1273 * Send NS packet for DAD, ip6_dad_count times. 1274 * Note that we must delay the first transmission, if this is the 1275 * first packet to be sent from the interface after interface 1276 * (re)initialization. 1277 */ 1278 dp->dad_ifa = ifa; 1279 ifa_ref(ifa); /* just for safety */ 1280 dp->dad_count = V_ip6_dad_count; 1281 dp->dad_ns_icount = dp->dad_na_icount = 0; 1282 dp->dad_ns_ocount = dp->dad_ns_tcount = 0; 1283 if (delay == 0) { 1284 nd6_dad_ns_output(dp, ifa); 1285 nd6_dad_starttimer(dp, 1286 (long)ND_IFINFO(ifa->ifa_ifp)->retrans * hz / 1000); 1287 } else { 1288 nd6_dad_starttimer(dp, delay); 1289 } 1290} 1291 1292/* 1293 * terminate DAD unconditionally. used for address removals. 1294 */ 1295void 1296nd6_dad_stop(struct ifaddr *ifa) 1297{ 1298 struct dadq *dp; 1299 1300 if (DADQ_LOCK_INITIALIZED() == 0) 1301 return; 1302 dp = nd6_dad_find(ifa); 1303 if (!dp) { 1304 /* DAD wasn't started yet */ 1305 return; 1306 } 1307 1308 nd6_dad_stoptimer(dp); 1309 1310 DADQ_WLOCK(); 1311 TAILQ_REMOVE(&V_dadq, (struct dadq *)dp, dad_list); 1312 DADQ_WUNLOCK(); 1313 free(dp, M_IP6NDP); 1314 dp = NULL; 1315 ifa_free(ifa); 1316} 1317 1318static void 1319nd6_dad_timer(struct dadq *dp) 1320{ 1321 CURVNET_SET(dp->dad_vnet); 1322 struct ifaddr *ifa = dp->dad_ifa; 1323 struct ifnet *ifp = dp->dad_ifa->ifa_ifp; 1324 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1325 char ip6buf[INET6_ADDRSTRLEN]; 1326 1327 /* Sanity check */ 1328 if (ia == NULL) { 1329 log(LOG_ERR, "nd6_dad_timer: called with null parameter\n"); 1330 goto done; 1331 } 1332 if (ND_IFINFO(ifp)->flags & ND6_IFF_IFDISABLED) { 1333 /* Do not need DAD for ifdisabled interface. */ 1334 TAILQ_REMOVE(&V_dadq, (struct dadq *)dp, dad_list); 1335 log(LOG_ERR, "nd6_dad_timer: cancel DAD on %s because of " 1336 "ND6_IFF_IFDISABLED.\n", ifp->if_xname); 1337 free(dp, M_IP6NDP); 1338 dp = NULL; 1339 ifa_free(ifa); 1340 goto done; 1341 } 1342 if (ia->ia6_flags & IN6_IFF_DUPLICATED) { 1343 log(LOG_ERR, "nd6_dad_timer: called with duplicated address " 1344 "%s(%s)\n", 1345 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr), 1346 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1347 goto done; 1348 } 1349 if ((ia->ia6_flags & IN6_IFF_TENTATIVE) == 0) { 1350 log(LOG_ERR, "nd6_dad_timer: called with non-tentative address " 1351 "%s(%s)\n", 1352 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr), 1353 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1354 goto done; 1355 } 1356 1357 /* timeouted with IFF_{RUNNING,UP} check */ 1358 if (dp->dad_ns_tcount > V_dad_maxtry) { 1359 nd6log((LOG_INFO, "%s: could not run DAD, driver problem?\n", 1360 if_name(ifa->ifa_ifp))); 1361 1362 DADQ_WLOCK(); 1363 TAILQ_REMOVE(&V_dadq, (struct dadq *)dp, dad_list); 1364 DADQ_WUNLOCK(); 1365 free(dp, M_IP6NDP); 1366 dp = NULL; 1367 ifa_free(ifa); 1368 goto done; 1369 } 1370 1371 /* Need more checks? */ 1372 if (dp->dad_ns_ocount < dp->dad_count) { 1373 /* 1374 * We have more NS to go. Send NS packet for DAD. 1375 */ 1376 nd6_dad_ns_output(dp, ifa); 1377 nd6_dad_starttimer(dp, 1378 (long)ND_IFINFO(ifa->ifa_ifp)->retrans * hz / 1000); 1379 } else { 1380 /* 1381 * We have transmitted sufficient number of DAD packets. 1382 * See what we've got. 1383 */ 1384 int duplicate; 1385 1386 duplicate = 0; 1387 1388 if (dp->dad_na_icount) { 1389 /* 1390 * the check is in nd6_dad_na_input(), 1391 * but just in case 1392 */ 1393 duplicate++; 1394 } 1395 1396 if (dp->dad_ns_icount) { 1397 /* We've seen NS, means DAD has failed. */ 1398 duplicate++; 1399 } 1400 1401 if (duplicate) { 1402 /* (*dp) will be freed in nd6_dad_duplicated() */ 1403 dp = NULL; 1404 nd6_dad_duplicated(ifa); 1405 } else { 1406 /* 1407 * We are done with DAD. No NA came, no NS came. 1408 * No duplicate address found. Check IFDISABLED flag 1409 * again in case that it is changed between the 1410 * beginning of this function and here. 1411 */ 1412 if ((ND_IFINFO(ifp)->flags & ND6_IFF_IFDISABLED) == 0) 1413 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1414 1415 nd6log((LOG_DEBUG, 1416 "%s: DAD complete for %s - no duplicates found\n", 1417 if_name(ifa->ifa_ifp), 1418 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr))); 1419 1420 DADQ_WLOCK(); 1421 TAILQ_REMOVE(&V_dadq, (struct dadq *)dp, dad_list); 1422 DADQ_WUNLOCK(); 1423 free(dp, M_IP6NDP); 1424 dp = NULL; 1425 ifa_free(ifa); 1426 } 1427 } 1428 1429done: 1430 CURVNET_RESTORE(); 1431} 1432 1433void 1434nd6_dad_duplicated(struct ifaddr *ifa) 1435{ 1436 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1437 struct ifnet *ifp; 1438 struct dadq *dp; 1439 char ip6buf[INET6_ADDRSTRLEN]; 1440 1441 dp = nd6_dad_find(ifa); 1442 if (dp == NULL) { 1443 log(LOG_ERR, "nd6_dad_duplicated: DAD structure not found\n"); 1444 return; 1445 } 1446 1447 log(LOG_ERR, "%s: DAD detected duplicate IPv6 address %s: " 1448 "NS in/out=%d/%d, NA in=%d\n", 1449 if_name(ifa->ifa_ifp), ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr), 1450 dp->dad_ns_icount, dp->dad_ns_ocount, dp->dad_na_icount); 1451 1452 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1453 ia->ia6_flags |= IN6_IFF_DUPLICATED; 1454 1455 /* We are done with DAD, with duplicate address found. (failure) */ 1456 nd6_dad_stoptimer(dp); 1457 1458 ifp = ifa->ifa_ifp; 1459 log(LOG_ERR, "%s: DAD complete for %s - duplicate found\n", 1460 if_name(ifp), ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr)); 1461 log(LOG_ERR, "%s: manual intervention required\n", 1462 if_name(ifp)); 1463 1464 /* 1465 * If the address is a link-local address formed from an interface 1466 * identifier based on the hardware address which is supposed to be 1467 * uniquely assigned (e.g., EUI-64 for an Ethernet interface), IP 1468 * operation on the interface SHOULD be disabled. 1469 * [RFC 4862, Section 5.4.5] 1470 */ 1471 if (IN6_IS_ADDR_LINKLOCAL(&ia->ia_addr.sin6_addr)) { 1472 struct in6_addr in6; 1473 1474 /* 1475 * To avoid over-reaction, we only apply this logic when we are 1476 * very sure that hardware addresses are supposed to be unique. 1477 */ 1478 switch (ifp->if_type) { 1479 case IFT_ETHER: 1480 case IFT_FDDI: 1481 case IFT_ATM: 1482 case IFT_IEEE1394: 1483#ifdef IFT_IEEE80211 1484 case IFT_IEEE80211: 1485#endif 1486 case IFT_INFINIBAND: 1487 in6 = ia->ia_addr.sin6_addr; 1488 if (in6_get_hw_ifid(ifp, &in6) == 0 && 1489 IN6_ARE_ADDR_EQUAL(&ia->ia_addr.sin6_addr, &in6)) { 1490 ND_IFINFO(ifp)->flags |= ND6_IFF_IFDISABLED; 1491 log(LOG_ERR, "%s: possible hardware address " 1492 "duplication detected, disable IPv6\n", 1493 if_name(ifp)); 1494 } 1495 break; 1496 } 1497 } 1498 1499 DADQ_WLOCK(); 1500 TAILQ_REMOVE(&V_dadq, (struct dadq *)dp, dad_list); 1501 DADQ_WUNLOCK(); 1502 free(dp, M_IP6NDP); 1503 dp = NULL; 1504 ifa_free(ifa); 1505} 1506 1507static void 1508nd6_dad_ns_output(struct dadq *dp, struct ifaddr *ifa) 1509{ 1510 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1511 struct ifnet *ifp = ifa->ifa_ifp; 1512 1513 dp->dad_ns_tcount++; 1514 if ((ifp->if_flags & IFF_UP) == 0) { 1515 return; 1516 } 1517 if ((ifp->if_drv_flags & IFF_DRV_RUNNING) == 0) { 1518 return; 1519 } 1520 1521 dp->dad_ns_ocount++; 1522 nd6_ns_output(ifp, NULL, &ia->ia_addr.sin6_addr, NULL, 1); 1523} 1524 1525static void 1526nd6_dad_ns_input(struct ifaddr *ifa) 1527{ 1528 struct in6_ifaddr *ia; 1529 struct ifnet *ifp; 1530 const struct in6_addr *taddr6; 1531 struct dadq *dp; 1532 int duplicate; 1533 1534 if (ifa == NULL) 1535 panic("ifa == NULL in nd6_dad_ns_input"); 1536 1537 ia = (struct in6_ifaddr *)ifa; 1538 ifp = ifa->ifa_ifp; 1539 taddr6 = &ia->ia_addr.sin6_addr; 1540 duplicate = 0; 1541 dp = nd6_dad_find(ifa); 1542 1543 /* Quickhack - completely ignore DAD NS packets */ 1544 if (V_dad_ignore_ns) { 1545 char ip6buf[INET6_ADDRSTRLEN]; 1546 nd6log((LOG_INFO, 1547 "nd6_dad_ns_input: ignoring DAD NS packet for " 1548 "address %s(%s)\n", ip6_sprintf(ip6buf, taddr6), 1549 if_name(ifa->ifa_ifp))); 1550 return; 1551 } 1552 1553 /* 1554 * if I'm yet to start DAD, someone else started using this address 1555 * first. I have a duplicate and you win. 1556 */ 1557 if (dp == NULL || dp->dad_ns_ocount == 0) 1558 duplicate++; 1559 1560 /* XXX more checks for loopback situation - see nd6_dad_timer too */ 1561 1562 if (duplicate) { 1563 dp = NULL; /* will be freed in nd6_dad_duplicated() */ 1564 nd6_dad_duplicated(ifa); 1565 } else { 1566 /* 1567 * not sure if I got a duplicate. 1568 * increment ns count and see what happens. 1569 */ 1570 if (dp) 1571 dp->dad_ns_icount++; 1572 } 1573} 1574 1575static void 1576nd6_dad_na_input(struct ifaddr *ifa) 1577{ 1578 struct dadq *dp; 1579 1580 if (ifa == NULL) 1581 panic("ifa == NULL in nd6_dad_na_input"); 1582 1583 dp = nd6_dad_find(ifa); 1584 if (dp) 1585 dp->dad_na_icount++; 1586 1587 /* remove the address. */ 1588 nd6_dad_duplicated(ifa); 1589} 1590