nd6_nbr.c revision 273188
1193833Sjhb/*- 2193833Sjhb * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project. 3193833Sjhb * All rights reserved. 4193833Sjhb * 5193833Sjhb * Redistribution and use in source and binary forms, with or without 6193833Sjhb * modification, are permitted provided that the following conditions 7193833Sjhb * are met: 8193833Sjhb * 1. Redistributions of source code must retain the above copyright 9193833Sjhb * notice, this list of conditions and the following disclaimer. 10193833Sjhb * 2. Redistributions in binary form must reproduce the above copyright 11193833Sjhb * notice, this list of conditions and the following disclaimer in the 12193833Sjhb * documentation and/or other materials provided with the distribution. 13193833Sjhb * 3. Neither the name of the project nor the names of its contributors 14193833Sjhb * may be used to endorse or promote products derived from this software 15193833Sjhb * without specific prior written permission. 16193833Sjhb * 17193833Sjhb * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND 18193833Sjhb * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19193833Sjhb * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20193833Sjhb * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE 21193833Sjhb * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22193833Sjhb * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23193833Sjhb * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24193833Sjhb * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25193833Sjhb * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26193833Sjhb * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27193833Sjhb * SUCH DAMAGE. 28193833Sjhb * 29193833Sjhb * $KAME: nd6_nbr.c,v 1.86 2002/01/21 02:33:04 jinmei Exp $ 30193833Sjhb */ 31209031Suqs 32193833Sjhb#include <sys/cdefs.h> 33193833Sjhb__FBSDID("$FreeBSD: releng/10.1/sys/netinet6/nd6_nbr.c 273188 2014-10-16 22:00:24Z hrs $"); 34193833Sjhb 35193833Sjhb#include "opt_inet.h" 36193833Sjhb#include "opt_inet6.h" 37193833Sjhb#include "opt_ipsec.h" 38193833Sjhb#include "opt_mpath.h" 39193833Sjhb 40193833Sjhb#include <sys/param.h> 41193833Sjhb#include <sys/systm.h> 42193833Sjhb#include <sys/malloc.h> 43193833Sjhb#include <sys/lock.h> 44193833Sjhb#include <sys/rwlock.h> 45193833Sjhb#include <sys/mbuf.h> 46193833Sjhb#include <sys/socket.h> 47193833Sjhb#include <sys/sockio.h> 48193833Sjhb#include <sys/time.h> 49193833Sjhb#include <sys/kernel.h> 50193833Sjhb#include <sys/errno.h> 51193833Sjhb#include <sys/syslog.h> 52193833Sjhb#include <sys/queue.h> 53193833Sjhb#include <sys/callout.h> 54193833Sjhb 55193833Sjhb#include <net/if.h> 56193833Sjhb#include <net/if_types.h> 57193833Sjhb#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 if (max_linkhdr + maxlen >= MCLBYTES) { 404#ifdef DIAGNOSTIC 405 printf("nd6_ns_output: max_linkhdr + maxlen >= MCLBYTES " 406 "(%d + %d > %d)\n", max_linkhdr, maxlen, MCLBYTES); 407#endif 408 return; 409 } 410 411 if (max_linkhdr + maxlen > MHLEN) 412 m = m_getcl(M_NOWAIT, MT_DATA, M_PKTHDR); 413 else 414 m = m_gethdr(M_NOWAIT, MT_DATA); 415 if (m == NULL) 416 return; 417 418 bzero(&ro, sizeof(ro)); 419 420 if (daddr6 == NULL || IN6_IS_ADDR_MULTICAST(daddr6)) { 421 m->m_flags |= M_MCAST; 422 im6o.im6o_multicast_ifp = ifp; 423 im6o.im6o_multicast_hlim = 255; 424 im6o.im6o_multicast_loop = 0; 425 } 426 427 icmp6len = sizeof(*nd_ns); 428 m->m_pkthdr.len = m->m_len = sizeof(*ip6) + icmp6len; 429 m->m_data += max_linkhdr; /* or MH_ALIGN() equivalent? */ 430 431 /* fill neighbor solicitation packet */ 432 ip6 = mtod(m, struct ip6_hdr *); 433 ip6->ip6_flow = 0; 434 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 435 ip6->ip6_vfc |= IPV6_VERSION; 436 /* ip6->ip6_plen will be set later */ 437 ip6->ip6_nxt = IPPROTO_ICMPV6; 438 ip6->ip6_hlim = 255; 439 if (daddr6) 440 ip6->ip6_dst = *daddr6; 441 else { 442 ip6->ip6_dst.s6_addr16[0] = IPV6_ADDR_INT16_MLL; 443 ip6->ip6_dst.s6_addr16[1] = 0; 444 ip6->ip6_dst.s6_addr32[1] = 0; 445 ip6->ip6_dst.s6_addr32[2] = IPV6_ADDR_INT32_ONE; 446 ip6->ip6_dst.s6_addr32[3] = taddr6->s6_addr32[3]; 447 ip6->ip6_dst.s6_addr8[12] = 0xff; 448 if (in6_setscope(&ip6->ip6_dst, ifp, NULL) != 0) 449 goto bad; 450 } 451 if (!dad) { 452 struct ifaddr *ifa; 453 454 /* 455 * RFC2461 7.2.2: 456 * "If the source address of the packet prompting the 457 * solicitation is the same as one of the addresses assigned 458 * to the outgoing interface, that address SHOULD be placed 459 * in the IP Source Address of the outgoing solicitation. 460 * Otherwise, any one of the addresses assigned to the 461 * interface should be used." 462 * 463 * We use the source address for the prompting packet 464 * (saddr6), if: 465 * - saddr6 is given from the caller (by giving "ln"), and 466 * - saddr6 belongs to the outgoing interface. 467 * Otherwise, we perform the source address selection as usual. 468 */ 469 struct in6_addr *hsrc; 470 471 hsrc = NULL; 472 if (ln != NULL) { 473 LLE_RLOCK(ln); 474 if (ln->la_hold != NULL) { 475 struct ip6_hdr *hip6; /* hold ip6 */ 476 477 /* 478 * assuming every packet in la_hold has the same IP 479 * header 480 */ 481 hip6 = mtod(ln->la_hold, struct ip6_hdr *); 482 /* XXX pullup? */ 483 if (sizeof(*hip6) < ln->la_hold->m_len) { 484 ip6->ip6_src = hip6->ip6_src; 485 hsrc = &hip6->ip6_src; 486 } 487 } 488 LLE_RUNLOCK(ln); 489 } 490 if (hsrc && (ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, 491 hsrc)) != NULL) { 492 /* ip6_src set already. */ 493 ifa_free(ifa); 494 } else { 495 int error; 496 struct sockaddr_in6 dst_sa; 497 struct in6_addr src_in; 498 struct ifnet *oifp; 499 500 bzero(&dst_sa, sizeof(dst_sa)); 501 dst_sa.sin6_family = AF_INET6; 502 dst_sa.sin6_len = sizeof(dst_sa); 503 dst_sa.sin6_addr = ip6->ip6_dst; 504 505 oifp = ifp; 506 error = in6_selectsrc(&dst_sa, NULL, 507 NULL, &ro, NULL, &oifp, &src_in); 508 if (error) { 509 char ip6buf[INET6_ADDRSTRLEN]; 510 nd6log((LOG_DEBUG, 511 "nd6_ns_output: source can't be " 512 "determined: dst=%s, error=%d\n", 513 ip6_sprintf(ip6buf, &dst_sa.sin6_addr), 514 error)); 515 goto bad; 516 } 517 ip6->ip6_src = src_in; 518 } 519 } else { 520 /* 521 * Source address for DAD packet must always be IPv6 522 * unspecified address. (0::0) 523 * We actually don't have to 0-clear the address (we did it 524 * above), but we do so here explicitly to make the intention 525 * clearer. 526 */ 527 bzero(&ip6->ip6_src, sizeof(ip6->ip6_src)); 528 } 529 nd_ns = (struct nd_neighbor_solicit *)(ip6 + 1); 530 nd_ns->nd_ns_type = ND_NEIGHBOR_SOLICIT; 531 nd_ns->nd_ns_code = 0; 532 nd_ns->nd_ns_reserved = 0; 533 nd_ns->nd_ns_target = *taddr6; 534 in6_clearscope(&nd_ns->nd_ns_target); /* XXX */ 535 536 /* 537 * Add source link-layer address option. 538 * 539 * spec implementation 540 * --- --- 541 * DAD packet MUST NOT do not add the option 542 * there's no link layer address: 543 * impossible do not add the option 544 * there's link layer address: 545 * Multicast NS MUST add one add the option 546 * Unicast NS SHOULD add one add the option 547 */ 548 if (!dad && (mac = nd6_ifptomac(ifp))) { 549 int optlen = sizeof(struct nd_opt_hdr) + ifp->if_addrlen; 550 struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)(nd_ns + 1); 551 /* 8 byte alignments... */ 552 optlen = (optlen + 7) & ~7; 553 554 m->m_pkthdr.len += optlen; 555 m->m_len += optlen; 556 icmp6len += optlen; 557 bzero((caddr_t)nd_opt, optlen); 558 nd_opt->nd_opt_type = ND_OPT_SOURCE_LINKADDR; 559 nd_opt->nd_opt_len = optlen >> 3; 560 bcopy(mac, (caddr_t)(nd_opt + 1), ifp->if_addrlen); 561 } 562 563 ip6->ip6_plen = htons((u_short)icmp6len); 564 nd_ns->nd_ns_cksum = 0; 565 nd_ns->nd_ns_cksum = 566 in6_cksum(m, IPPROTO_ICMPV6, sizeof(*ip6), icmp6len); 567 568 if (send_sendso_input_hook != NULL) { 569 mtag = m_tag_get(PACKET_TAG_ND_OUTGOING, 570 sizeof(unsigned short), M_NOWAIT); 571 if (mtag == NULL) 572 goto bad; 573 *(unsigned short *)(mtag + 1) = nd_ns->nd_ns_type; 574 m_tag_prepend(m, mtag); 575 } 576 577 ip6_output(m, NULL, &ro, dad ? IPV6_UNSPECSRC : 0, &im6o, NULL, NULL); 578 icmp6_ifstat_inc(ifp, ifs6_out_msg); 579 icmp6_ifstat_inc(ifp, ifs6_out_neighborsolicit); 580 ICMP6STAT_INC(icp6s_outhist[ND_NEIGHBOR_SOLICIT]); 581 582 /* We don't cache this route. */ 583 RO_RTFREE(&ro); 584 585 return; 586 587 bad: 588 if (ro.ro_rt) { 589 RTFREE(ro.ro_rt); 590 } 591 m_freem(m); 592 return; 593} 594 595/* 596 * Neighbor advertisement input handling. 597 * 598 * Based on RFC 2461 599 * Based on RFC 2462 (duplicate address detection) 600 * 601 * the following items are not implemented yet: 602 * - proxy advertisement delay rule (RFC2461 7.2.8, last paragraph, SHOULD) 603 * - anycast advertisement delay rule (RFC2461 7.2.7, SHOULD) 604 */ 605void 606nd6_na_input(struct mbuf *m, int off, int icmp6len) 607{ 608 struct ifnet *ifp = m->m_pkthdr.rcvif; 609 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 610 struct nd_neighbor_advert *nd_na; 611 struct in6_addr daddr6 = ip6->ip6_dst; 612 struct in6_addr taddr6; 613 int flags; 614 int is_router; 615 int is_solicited; 616 int is_override; 617 char *lladdr = NULL; 618 int lladdrlen = 0; 619 int checklink = 0; 620 struct ifaddr *ifa; 621 struct llentry *ln = NULL; 622 union nd_opts ndopts; 623 struct mbuf *chain = NULL; 624 struct m_tag *mtag; 625 struct sockaddr_in6 sin6; 626 char ip6bufs[INET6_ADDRSTRLEN], ip6bufd[INET6_ADDRSTRLEN]; 627 628 if (ip6->ip6_hlim != 255) { 629 nd6log((LOG_ERR, 630 "nd6_na_input: invalid hlim (%d) from %s to %s on %s\n", 631 ip6->ip6_hlim, ip6_sprintf(ip6bufs, &ip6->ip6_src), 632 ip6_sprintf(ip6bufd, &ip6->ip6_dst), if_name(ifp))); 633 goto bad; 634 } 635 636#ifndef PULLDOWN_TEST 637 IP6_EXTHDR_CHECK(m, off, icmp6len,); 638 nd_na = (struct nd_neighbor_advert *)((caddr_t)ip6 + off); 639#else 640 IP6_EXTHDR_GET(nd_na, struct nd_neighbor_advert *, m, off, icmp6len); 641 if (nd_na == NULL) { 642 ICMP6STAT_INC(icp6s_tooshort); 643 return; 644 } 645#endif 646 647 flags = nd_na->nd_na_flags_reserved; 648 is_router = ((flags & ND_NA_FLAG_ROUTER) != 0); 649 is_solicited = ((flags & ND_NA_FLAG_SOLICITED) != 0); 650 is_override = ((flags & ND_NA_FLAG_OVERRIDE) != 0); 651 652 taddr6 = nd_na->nd_na_target; 653 if (in6_setscope(&taddr6, ifp, NULL)) 654 goto bad; /* XXX: impossible */ 655 656 if (IN6_IS_ADDR_MULTICAST(&taddr6)) { 657 nd6log((LOG_ERR, 658 "nd6_na_input: invalid target address %s\n", 659 ip6_sprintf(ip6bufs, &taddr6))); 660 goto bad; 661 } 662 if (IN6_IS_ADDR_MULTICAST(&daddr6)) 663 if (is_solicited) { 664 nd6log((LOG_ERR, 665 "nd6_na_input: a solicited adv is multicasted\n")); 666 goto bad; 667 } 668 669 icmp6len -= sizeof(*nd_na); 670 nd6_option_init(nd_na + 1, icmp6len, &ndopts); 671 if (nd6_options(&ndopts) < 0) { 672 nd6log((LOG_INFO, 673 "nd6_na_input: invalid ND option, ignored\n")); 674 /* nd6_options have incremented stats */ 675 goto freeit; 676 } 677 678 if (ndopts.nd_opts_tgt_lladdr) { 679 lladdr = (char *)(ndopts.nd_opts_tgt_lladdr + 1); 680 lladdrlen = ndopts.nd_opts_tgt_lladdr->nd_opt_len << 3; 681 } 682 683 /* 684 * This effectively disables the DAD check on a non-master CARP 685 * address. 686 */ 687 if (ifp->if_carp) 688 ifa = (*carp_iamatch6_p)(ifp, &taddr6); 689 else 690 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &taddr6); 691 692 /* 693 * Target address matches one of my interface address. 694 * 695 * If my address is tentative, this means that there's somebody 696 * already using the same address as mine. This indicates DAD failure. 697 * This is defined in RFC 2462. 698 * 699 * Otherwise, process as defined in RFC 2461. 700 */ 701 if (ifa 702 && (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_TENTATIVE)) { 703 ifa_free(ifa); 704 nd6_dad_na_input(ifa); 705 goto freeit; 706 } 707 708 /* Just for safety, maybe unnecessary. */ 709 if (ifa) { 710 ifa_free(ifa); 711 log(LOG_ERR, 712 "nd6_na_input: duplicate IP6 address %s\n", 713 ip6_sprintf(ip6bufs, &taddr6)); 714 goto freeit; 715 } 716 717 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) { 718 nd6log((LOG_INFO, "nd6_na_input: lladdrlen mismatch for %s " 719 "(if %d, NA packet %d)\n", ip6_sprintf(ip6bufs, &taddr6), 720 ifp->if_addrlen, lladdrlen - 2)); 721 goto bad; 722 } 723 724 /* 725 * If no neighbor cache entry is found, NA SHOULD silently be 726 * discarded. 727 */ 728 IF_AFDATA_RLOCK(ifp); 729 ln = nd6_lookup(&taddr6, LLE_EXCLUSIVE, ifp); 730 IF_AFDATA_RUNLOCK(ifp); 731 if (ln == NULL) { 732 goto freeit; 733 } 734 735 if (ln->ln_state == ND6_LLINFO_INCOMPLETE) { 736 /* 737 * If the link-layer has address, and no lladdr option came, 738 * discard the packet. 739 */ 740 if (ifp->if_addrlen && lladdr == NULL) { 741 goto freeit; 742 } 743 744 /* 745 * Record link-layer address, and update the state. 746 */ 747 bcopy(lladdr, &ln->ll_addr, ifp->if_addrlen); 748 ln->la_flags |= LLE_VALID; 749 EVENTHANDLER_INVOKE(lle_event, ln, LLENTRY_RESOLVED); 750 if (is_solicited) { 751 ln->ln_state = ND6_LLINFO_REACHABLE; 752 ln->ln_byhint = 0; 753 if (!ND6_LLINFO_PERMANENT(ln)) { 754 nd6_llinfo_settimer_locked(ln, 755 (long)ND_IFINFO(ln->lle_tbl->llt_ifp)->reachable * hz); 756 } 757 } else { 758 ln->ln_state = ND6_LLINFO_STALE; 759 nd6_llinfo_settimer_locked(ln, (long)V_nd6_gctimer * hz); 760 } 761 if ((ln->ln_router = is_router) != 0) { 762 /* 763 * This means a router's state has changed from 764 * non-reachable to probably reachable, and might 765 * affect the status of associated prefixes.. 766 */ 767 checklink = 1; 768 } 769 } else { 770 int llchange; 771 772 /* 773 * Check if the link-layer address has changed or not. 774 */ 775 if (lladdr == NULL) 776 llchange = 0; 777 else { 778 if (ln->la_flags & LLE_VALID) { 779 if (bcmp(lladdr, &ln->ll_addr, ifp->if_addrlen)) 780 llchange = 1; 781 else 782 llchange = 0; 783 } else 784 llchange = 1; 785 } 786 787 /* 788 * This is VERY complex. Look at it with care. 789 * 790 * override solicit lladdr llchange action 791 * (L: record lladdr) 792 * 793 * 0 0 n -- (2c) 794 * 0 0 y n (2b) L 795 * 0 0 y y (1) REACHABLE->STALE 796 * 0 1 n -- (2c) *->REACHABLE 797 * 0 1 y n (2b) L *->REACHABLE 798 * 0 1 y y (1) REACHABLE->STALE 799 * 1 0 n -- (2a) 800 * 1 0 y n (2a) L 801 * 1 0 y y (2a) L *->STALE 802 * 1 1 n -- (2a) *->REACHABLE 803 * 1 1 y n (2a) L *->REACHABLE 804 * 1 1 y y (2a) L *->REACHABLE 805 */ 806 if (!is_override && (lladdr != NULL && llchange)) { /* (1) */ 807 /* 808 * If state is REACHABLE, make it STALE. 809 * no other updates should be done. 810 */ 811 if (ln->ln_state == ND6_LLINFO_REACHABLE) { 812 ln->ln_state = ND6_LLINFO_STALE; 813 nd6_llinfo_settimer_locked(ln, (long)V_nd6_gctimer * hz); 814 } 815 goto freeit; 816 } else if (is_override /* (2a) */ 817 || (!is_override && (lladdr != NULL && !llchange)) /* (2b) */ 818 || lladdr == NULL) { /* (2c) */ 819 /* 820 * Update link-local address, if any. 821 */ 822 if (lladdr != NULL) { 823 bcopy(lladdr, &ln->ll_addr, ifp->if_addrlen); 824 ln->la_flags |= LLE_VALID; 825 EVENTHANDLER_INVOKE(lle_event, ln, 826 LLENTRY_RESOLVED); 827 } 828 829 /* 830 * If solicited, make the state REACHABLE. 831 * If not solicited and the link-layer address was 832 * changed, make it STALE. 833 */ 834 if (is_solicited) { 835 ln->ln_state = ND6_LLINFO_REACHABLE; 836 ln->ln_byhint = 0; 837 if (!ND6_LLINFO_PERMANENT(ln)) { 838 nd6_llinfo_settimer_locked(ln, 839 (long)ND_IFINFO(ifp)->reachable * hz); 840 } 841 } else { 842 if (lladdr != NULL && llchange) { 843 ln->ln_state = ND6_LLINFO_STALE; 844 nd6_llinfo_settimer_locked(ln, 845 (long)V_nd6_gctimer * hz); 846 } 847 } 848 } 849 850 if (ln->ln_router && !is_router) { 851 /* 852 * The peer dropped the router flag. 853 * Remove the sender from the Default Router List and 854 * update the Destination Cache entries. 855 */ 856 struct nd_defrouter *dr; 857 struct in6_addr *in6; 858 859 in6 = &L3_ADDR_SIN6(ln)->sin6_addr; 860 861 /* 862 * Lock to protect the default router list. 863 * XXX: this might be unnecessary, since this function 864 * is only called under the network software interrupt 865 * context. However, we keep it just for safety. 866 */ 867 dr = defrouter_lookup(in6, ln->lle_tbl->llt_ifp); 868 if (dr) 869 defrtrlist_del(dr); 870 else if (ND_IFINFO(ln->lle_tbl->llt_ifp)->flags & 871 ND6_IFF_ACCEPT_RTADV) { 872 /* 873 * Even if the neighbor is not in the default 874 * router list, the neighbor may be used 875 * as a next hop for some destinations 876 * (e.g. redirect case). So we must 877 * call rt6_flush explicitly. 878 */ 879 rt6_flush(&ip6->ip6_src, ifp); 880 } 881 } 882 ln->ln_router = is_router; 883 } 884 /* XXX - QL 885 * Does this matter? 886 * rt->rt_flags &= ~RTF_REJECT; 887 */ 888 ln->la_asked = 0; 889 if (ln->la_hold) { 890 struct mbuf *m_hold, *m_hold_next; 891 892 /* 893 * reset the la_hold in advance, to explicitly 894 * prevent a la_hold lookup in nd6_output() 895 * (wouldn't happen, though...) 896 */ 897 for (m_hold = ln->la_hold, ln->la_hold = NULL; 898 m_hold; m_hold = m_hold_next) { 899 m_hold_next = m_hold->m_nextpkt; 900 m_hold->m_nextpkt = NULL; 901 /* 902 * we assume ifp is not a loopback here, so just set 903 * the 2nd argument as the 1st one. 904 */ 905 906 if (send_sendso_input_hook != NULL) { 907 mtag = m_tag_get(PACKET_TAG_ND_OUTGOING, 908 sizeof(unsigned short), M_NOWAIT); 909 if (mtag == NULL) 910 goto bad; 911 m_tag_prepend(m, mtag); 912 } 913 914 nd6_output_lle(ifp, ifp, m_hold, L3_ADDR_SIN6(ln), NULL, ln, &chain); 915 } 916 } 917 freeit: 918 if (ln != NULL) { 919 if (chain) 920 memcpy(&sin6, L3_ADDR_SIN6(ln), sizeof(sin6)); 921 LLE_WUNLOCK(ln); 922 923 if (chain) 924 nd6_output_flush(ifp, ifp, chain, &sin6, NULL); 925 } 926 if (checklink) 927 pfxlist_onlink_check(); 928 929 m_freem(m); 930 return; 931 932 bad: 933 if (ln != NULL) 934 LLE_WUNLOCK(ln); 935 936 ICMP6STAT_INC(icp6s_badna); 937 m_freem(m); 938} 939 940/* 941 * Neighbor advertisement output handling. 942 * 943 * Based on RFC 2461 944 * 945 * the following items are not implemented yet: 946 * - proxy advertisement delay rule (RFC2461 7.2.8, last paragraph, SHOULD) 947 * - anycast advertisement delay rule (RFC2461 7.2.7, SHOULD) 948 * 949 * tlladdr - 1 if include target link-layer address 950 * sdl0 - sockaddr_dl (= proxy NA) or NULL 951 */ 952static void 953nd6_na_output_fib(struct ifnet *ifp, const struct in6_addr *daddr6_0, 954 const struct in6_addr *taddr6, u_long flags, int tlladdr, 955 struct sockaddr *sdl0, u_int fibnum) 956{ 957 struct mbuf *m; 958 struct m_tag *mtag; 959 struct ifnet *oifp; 960 struct ip6_hdr *ip6; 961 struct nd_neighbor_advert *nd_na; 962 struct ip6_moptions im6o; 963 struct in6_addr src, daddr6; 964 struct sockaddr_in6 dst_sa; 965 int icmp6len, maxlen, error; 966 caddr_t mac = NULL; 967 struct route_in6 ro; 968 969 bzero(&ro, sizeof(ro)); 970 971 daddr6 = *daddr6_0; /* make a local copy for modification */ 972 973 /* estimate the size of message */ 974 maxlen = sizeof(*ip6) + sizeof(*nd_na); 975 maxlen += (sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7; 976 if (max_linkhdr + maxlen >= MCLBYTES) { 977#ifdef DIAGNOSTIC 978 printf("nd6_na_output: max_linkhdr + maxlen >= MCLBYTES " 979 "(%d + %d > %d)\n", max_linkhdr, maxlen, MCLBYTES); 980#endif 981 return; 982 } 983 984 if (max_linkhdr + maxlen > MHLEN) 985 m = m_getcl(M_NOWAIT, MT_DATA, M_PKTHDR); 986 else 987 m = m_gethdr(M_NOWAIT, MT_DATA); 988 if (m == NULL) 989 return; 990 M_SETFIB(m, fibnum); 991 992 if (IN6_IS_ADDR_MULTICAST(&daddr6)) { 993 m->m_flags |= M_MCAST; 994 im6o.im6o_multicast_ifp = ifp; 995 im6o.im6o_multicast_hlim = 255; 996 im6o.im6o_multicast_loop = 0; 997 } 998 999 icmp6len = sizeof(*nd_na); 1000 m->m_pkthdr.len = m->m_len = sizeof(struct ip6_hdr) + icmp6len; 1001 m->m_data += max_linkhdr; /* or MH_ALIGN() equivalent? */ 1002 1003 /* fill neighbor advertisement packet */ 1004 ip6 = mtod(m, struct ip6_hdr *); 1005 ip6->ip6_flow = 0; 1006 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 1007 ip6->ip6_vfc |= IPV6_VERSION; 1008 ip6->ip6_nxt = IPPROTO_ICMPV6; 1009 ip6->ip6_hlim = 255; 1010 if (IN6_IS_ADDR_UNSPECIFIED(&daddr6)) { 1011 /* reply to DAD */ 1012 daddr6.s6_addr16[0] = IPV6_ADDR_INT16_MLL; 1013 daddr6.s6_addr16[1] = 0; 1014 daddr6.s6_addr32[1] = 0; 1015 daddr6.s6_addr32[2] = 0; 1016 daddr6.s6_addr32[3] = IPV6_ADDR_INT32_ONE; 1017 if (in6_setscope(&daddr6, ifp, NULL)) 1018 goto bad; 1019 1020 flags &= ~ND_NA_FLAG_SOLICITED; 1021 } 1022 ip6->ip6_dst = daddr6; 1023 bzero(&dst_sa, sizeof(struct sockaddr_in6)); 1024 dst_sa.sin6_family = AF_INET6; 1025 dst_sa.sin6_len = sizeof(struct sockaddr_in6); 1026 dst_sa.sin6_addr = daddr6; 1027 1028 /* 1029 * Select a source whose scope is the same as that of the dest. 1030 */ 1031 bcopy(&dst_sa, &ro.ro_dst, sizeof(dst_sa)); 1032 oifp = ifp; 1033 error = in6_selectsrc(&dst_sa, NULL, NULL, &ro, NULL, &oifp, &src); 1034 if (error) { 1035 char ip6buf[INET6_ADDRSTRLEN]; 1036 nd6log((LOG_DEBUG, "nd6_na_output: source can't be " 1037 "determined: dst=%s, error=%d\n", 1038 ip6_sprintf(ip6buf, &dst_sa.sin6_addr), error)); 1039 goto bad; 1040 } 1041 ip6->ip6_src = src; 1042 nd_na = (struct nd_neighbor_advert *)(ip6 + 1); 1043 nd_na->nd_na_type = ND_NEIGHBOR_ADVERT; 1044 nd_na->nd_na_code = 0; 1045 nd_na->nd_na_target = *taddr6; 1046 in6_clearscope(&nd_na->nd_na_target); /* XXX */ 1047 1048 /* 1049 * "tlladdr" indicates NS's condition for adding tlladdr or not. 1050 * see nd6_ns_input() for details. 1051 * Basically, if NS packet is sent to unicast/anycast addr, 1052 * target lladdr option SHOULD NOT be included. 1053 */ 1054 if (tlladdr) { 1055 /* 1056 * sdl0 != NULL indicates proxy NA. If we do proxy, use 1057 * lladdr in sdl0. If we are not proxying (sending NA for 1058 * my address) use lladdr configured for the interface. 1059 */ 1060 if (sdl0 == NULL) { 1061 if (ifp->if_carp) 1062 mac = (*carp_macmatch6_p)(ifp, m, taddr6); 1063 if (mac == NULL) 1064 mac = nd6_ifptomac(ifp); 1065 } else if (sdl0->sa_family == AF_LINK) { 1066 struct sockaddr_dl *sdl; 1067 sdl = (struct sockaddr_dl *)sdl0; 1068 if (sdl->sdl_alen == ifp->if_addrlen) 1069 mac = LLADDR(sdl); 1070 } 1071 } 1072 if (tlladdr && mac) { 1073 int optlen = sizeof(struct nd_opt_hdr) + ifp->if_addrlen; 1074 struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)(nd_na + 1); 1075 1076 /* roundup to 8 bytes alignment! */ 1077 optlen = (optlen + 7) & ~7; 1078 1079 m->m_pkthdr.len += optlen; 1080 m->m_len += optlen; 1081 icmp6len += optlen; 1082 bzero((caddr_t)nd_opt, optlen); 1083 nd_opt->nd_opt_type = ND_OPT_TARGET_LINKADDR; 1084 nd_opt->nd_opt_len = optlen >> 3; 1085 bcopy(mac, (caddr_t)(nd_opt + 1), ifp->if_addrlen); 1086 } else 1087 flags &= ~ND_NA_FLAG_OVERRIDE; 1088 1089 ip6->ip6_plen = htons((u_short)icmp6len); 1090 nd_na->nd_na_flags_reserved = flags; 1091 nd_na->nd_na_cksum = 0; 1092 nd_na->nd_na_cksum = 1093 in6_cksum(m, IPPROTO_ICMPV6, sizeof(struct ip6_hdr), icmp6len); 1094 1095 if (send_sendso_input_hook != NULL) { 1096 mtag = m_tag_get(PACKET_TAG_ND_OUTGOING, 1097 sizeof(unsigned short), M_NOWAIT); 1098 if (mtag == NULL) 1099 goto bad; 1100 *(unsigned short *)(mtag + 1) = nd_na->nd_na_type; 1101 m_tag_prepend(m, mtag); 1102 } 1103 1104 ip6_output(m, NULL, &ro, 0, &im6o, NULL, NULL); 1105 icmp6_ifstat_inc(ifp, ifs6_out_msg); 1106 icmp6_ifstat_inc(ifp, ifs6_out_neighboradvert); 1107 ICMP6STAT_INC(icp6s_outhist[ND_NEIGHBOR_ADVERT]); 1108 1109 /* We don't cache this route. */ 1110 RO_RTFREE(&ro); 1111 1112 return; 1113 1114 bad: 1115 if (ro.ro_rt) { 1116 RTFREE(ro.ro_rt); 1117 } 1118 m_freem(m); 1119 return; 1120} 1121 1122#ifndef BURN_BRIDGES 1123void 1124nd6_na_output(struct ifnet *ifp, const struct in6_addr *daddr6_0, 1125 const struct in6_addr *taddr6, u_long flags, int tlladdr, 1126 struct sockaddr *sdl0) 1127{ 1128 1129 nd6_na_output_fib(ifp, daddr6_0, taddr6, flags, tlladdr, sdl0, 1130 RT_DEFAULT_FIB); 1131} 1132#endif 1133 1134caddr_t 1135nd6_ifptomac(struct ifnet *ifp) 1136{ 1137 switch (ifp->if_type) { 1138 case IFT_ARCNET: 1139 case IFT_ETHER: 1140 case IFT_FDDI: 1141 case IFT_IEEE1394: 1142#ifdef IFT_L2VLAN 1143 case IFT_L2VLAN: 1144#endif 1145#ifdef IFT_IEEE80211 1146 case IFT_IEEE80211: 1147#endif 1148 case IFT_INFINIBAND: 1149 case IFT_BRIDGE: 1150 case IFT_ISO88025: 1151 return IF_LLADDR(ifp); 1152 default: 1153 return NULL; 1154 } 1155} 1156 1157struct dadq { 1158 TAILQ_ENTRY(dadq) dad_list; 1159 struct ifaddr *dad_ifa; 1160 int dad_count; /* max NS to send */ 1161 int dad_ns_tcount; /* # of trials to send NS */ 1162 int dad_ns_ocount; /* NS sent so far */ 1163 int dad_ns_icount; 1164 int dad_na_icount; 1165 struct callout dad_timer_ch; 1166 struct vnet *dad_vnet; 1167}; 1168 1169static VNET_DEFINE(TAILQ_HEAD(, dadq), dadq); 1170static VNET_DEFINE(struct rwlock, dad_rwlock); 1171#define V_dadq VNET(dadq) 1172#define V_dad_rwlock VNET(dad_rwlock) 1173 1174#define DADQ_LOCK_INIT() rw_init(&V_dad_rwlock, "nd6 DAD queue") 1175#define DADQ_LOCK_DESTROY() rw_destroy(&V_dad_rwlock) 1176#define DADQ_LOCK_INITIALIZED() rw_initialized(&V_dad_rwlock) 1177#define DADQ_RLOCK() rw_rlock(&V_dad_rwlock) 1178#define DADQ_RUNLOCK() rw_runlock(&V_dad_rwlock) 1179#define DADQ_WLOCK() rw_wlock(&V_dad_rwlock) 1180#define DADQ_WUNLOCK() rw_wunlock(&V_dad_rwlock) 1181 1182static struct dadq * 1183nd6_dad_find(struct ifaddr *ifa) 1184{ 1185 struct dadq *dp; 1186 1187 DADQ_RLOCK(); 1188 TAILQ_FOREACH(dp, &V_dadq, dad_list) 1189 if (dp->dad_ifa == ifa) 1190 break; 1191 DADQ_RUNLOCK(); 1192 1193 return (dp); 1194} 1195 1196static void 1197nd6_dad_starttimer(struct dadq *dp, int ticks) 1198{ 1199 1200 callout_reset(&dp->dad_timer_ch, ticks, 1201 (void (*)(void *))nd6_dad_timer, (void *)dp); 1202} 1203 1204static void 1205nd6_dad_stoptimer(struct dadq *dp) 1206{ 1207 1208 callout_stop(&dp->dad_timer_ch); 1209} 1210 1211/* 1212 * Start Duplicate Address Detection (DAD) for specified interface address. 1213 */ 1214void 1215nd6_dad_start(struct ifaddr *ifa, int delay) 1216{ 1217 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1218 struct dadq *dp; 1219 char ip6buf[INET6_ADDRSTRLEN]; 1220 1221 if (DADQ_LOCK_INITIALIZED() == 0) { 1222 DADQ_LOCK_INIT(); 1223 TAILQ_INIT(&V_dadq); 1224 } 1225 1226 /* 1227 * If we don't need DAD, don't do it. 1228 * There are several cases: 1229 * - DAD is disabled (ip6_dad_count == 0) 1230 * - the interface address is anycast 1231 */ 1232 if (!(ia->ia6_flags & IN6_IFF_TENTATIVE)) { 1233 log(LOG_DEBUG, 1234 "nd6_dad_start: called with non-tentative address " 1235 "%s(%s)\n", 1236 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr), 1237 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1238 return; 1239 } 1240 if (ia->ia6_flags & IN6_IFF_ANYCAST) { 1241 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1242 return; 1243 } 1244 if (!V_ip6_dad_count) { 1245 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1246 return; 1247 } 1248 if (ifa->ifa_ifp == NULL) 1249 panic("nd6_dad_start: ifa->ifa_ifp == NULL"); 1250 if (!(ifa->ifa_ifp->if_flags & IFF_UP)) { 1251 return; 1252 } 1253 if (ND_IFINFO(ifa->ifa_ifp)->flags & ND6_IFF_IFDISABLED) 1254 return; 1255 if (nd6_dad_find(ifa) != NULL) { 1256 /* DAD already in progress */ 1257 return; 1258 } 1259 1260 dp = malloc(sizeof(*dp), M_IP6NDP, M_NOWAIT); 1261 if (dp == NULL) { 1262 log(LOG_ERR, "nd6_dad_start: memory allocation failed for " 1263 "%s(%s)\n", 1264 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr), 1265 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1266 return; 1267 } 1268 bzero(dp, sizeof(*dp)); 1269 callout_init(&dp->dad_timer_ch, 0); 1270#ifdef VIMAGE 1271 dp->dad_vnet = curvnet; 1272#endif 1273 DADQ_WLOCK(); 1274 TAILQ_INSERT_TAIL(&V_dadq, (struct dadq *)dp, dad_list); 1275 DADQ_WUNLOCK(); 1276 1277 nd6log((LOG_DEBUG, "%s: starting DAD for %s\n", if_name(ifa->ifa_ifp), 1278 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr))); 1279 1280 /* 1281 * Send NS packet for DAD, ip6_dad_count times. 1282 * Note that we must delay the first transmission, if this is the 1283 * first packet to be sent from the interface after interface 1284 * (re)initialization. 1285 */ 1286 dp->dad_ifa = ifa; 1287 ifa_ref(ifa); /* just for safety */ 1288 dp->dad_count = V_ip6_dad_count; 1289 dp->dad_ns_icount = dp->dad_na_icount = 0; 1290 dp->dad_ns_ocount = dp->dad_ns_tcount = 0; 1291 if (delay == 0) { 1292 nd6_dad_ns_output(dp, ifa); 1293 nd6_dad_starttimer(dp, 1294 (long)ND_IFINFO(ifa->ifa_ifp)->retrans * hz / 1000); 1295 } else { 1296 nd6_dad_starttimer(dp, delay); 1297 } 1298} 1299 1300/* 1301 * terminate DAD unconditionally. used for address removals. 1302 */ 1303void 1304nd6_dad_stop(struct ifaddr *ifa) 1305{ 1306 struct dadq *dp; 1307 1308 if (DADQ_LOCK_INITIALIZED() == 0) 1309 return; 1310 dp = nd6_dad_find(ifa); 1311 if (!dp) { 1312 /* DAD wasn't started yet */ 1313 return; 1314 } 1315 1316 nd6_dad_stoptimer(dp); 1317 1318 DADQ_WLOCK(); 1319 TAILQ_REMOVE(&V_dadq, (struct dadq *)dp, dad_list); 1320 DADQ_WUNLOCK(); 1321 free(dp, M_IP6NDP); 1322 dp = NULL; 1323 ifa_free(ifa); 1324} 1325 1326static void 1327nd6_dad_timer(struct dadq *dp) 1328{ 1329 CURVNET_SET(dp->dad_vnet); 1330 struct ifaddr *ifa = dp->dad_ifa; 1331 struct ifnet *ifp = dp->dad_ifa->ifa_ifp; 1332 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1333 char ip6buf[INET6_ADDRSTRLEN]; 1334 1335 /* Sanity check */ 1336 if (ia == NULL) { 1337 log(LOG_ERR, "nd6_dad_timer: called with null parameter\n"); 1338 goto done; 1339 } 1340 if (ND_IFINFO(ifp)->flags & ND6_IFF_IFDISABLED) { 1341 /* Do not need DAD for ifdisabled interface. */ 1342 TAILQ_REMOVE(&V_dadq, (struct dadq *)dp, dad_list); 1343 log(LOG_ERR, "nd6_dad_timer: cancel DAD on %s because of " 1344 "ND6_IFF_IFDISABLED.\n", ifp->if_xname); 1345 free(dp, M_IP6NDP); 1346 dp = NULL; 1347 ifa_free(ifa); 1348 goto done; 1349 } 1350 if (ia->ia6_flags & IN6_IFF_DUPLICATED) { 1351 log(LOG_ERR, "nd6_dad_timer: called with duplicated address " 1352 "%s(%s)\n", 1353 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr), 1354 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1355 goto done; 1356 } 1357 if ((ia->ia6_flags & IN6_IFF_TENTATIVE) == 0) { 1358 log(LOG_ERR, "nd6_dad_timer: called with non-tentative address " 1359 "%s(%s)\n", 1360 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr), 1361 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1362 goto done; 1363 } 1364 1365 /* timeouted with IFF_{RUNNING,UP} check */ 1366 if (dp->dad_ns_tcount > V_dad_maxtry) { 1367 nd6log((LOG_INFO, "%s: could not run DAD, driver problem?\n", 1368 if_name(ifa->ifa_ifp))); 1369 1370 DADQ_WLOCK(); 1371 TAILQ_REMOVE(&V_dadq, (struct dadq *)dp, dad_list); 1372 DADQ_WUNLOCK(); 1373 free(dp, M_IP6NDP); 1374 dp = NULL; 1375 ifa_free(ifa); 1376 goto done; 1377 } 1378 1379 /* Need more checks? */ 1380 if (dp->dad_ns_ocount < dp->dad_count) { 1381 /* 1382 * We have more NS to go. Send NS packet for DAD. 1383 */ 1384 nd6_dad_ns_output(dp, ifa); 1385 nd6_dad_starttimer(dp, 1386 (long)ND_IFINFO(ifa->ifa_ifp)->retrans * hz / 1000); 1387 } else { 1388 /* 1389 * We have transmitted sufficient number of DAD packets. 1390 * See what we've got. 1391 */ 1392 int duplicate; 1393 1394 duplicate = 0; 1395 1396 if (dp->dad_na_icount) { 1397 /* 1398 * the check is in nd6_dad_na_input(), 1399 * but just in case 1400 */ 1401 duplicate++; 1402 } 1403 1404 if (dp->dad_ns_icount) { 1405 /* We've seen NS, means DAD has failed. */ 1406 duplicate++; 1407 } 1408 1409 if (duplicate) { 1410 /* (*dp) will be freed in nd6_dad_duplicated() */ 1411 dp = NULL; 1412 nd6_dad_duplicated(ifa); 1413 } else { 1414 /* 1415 * We are done with DAD. No NA came, no NS came. 1416 * No duplicate address found. Check IFDISABLED flag 1417 * again in case that it is changed between the 1418 * beginning of this function and here. 1419 */ 1420 if ((ND_IFINFO(ifp)->flags & ND6_IFF_IFDISABLED) == 0) 1421 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1422 1423 nd6log((LOG_DEBUG, 1424 "%s: DAD complete for %s - no duplicates found\n", 1425 if_name(ifa->ifa_ifp), 1426 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr))); 1427 1428 DADQ_WLOCK(); 1429 TAILQ_REMOVE(&V_dadq, (struct dadq *)dp, dad_list); 1430 DADQ_WUNLOCK(); 1431 free(dp, M_IP6NDP); 1432 dp = NULL; 1433 ifa_free(ifa); 1434 } 1435 } 1436 1437done: 1438 CURVNET_RESTORE(); 1439} 1440 1441void 1442nd6_dad_duplicated(struct ifaddr *ifa) 1443{ 1444 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1445 struct ifnet *ifp; 1446 struct dadq *dp; 1447 char ip6buf[INET6_ADDRSTRLEN]; 1448 1449 dp = nd6_dad_find(ifa); 1450 if (dp == NULL) { 1451 log(LOG_ERR, "nd6_dad_duplicated: DAD structure not found\n"); 1452 return; 1453 } 1454 1455 log(LOG_ERR, "%s: DAD detected duplicate IPv6 address %s: " 1456 "NS in/out=%d/%d, NA in=%d\n", 1457 if_name(ifa->ifa_ifp), ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr), 1458 dp->dad_ns_icount, dp->dad_ns_ocount, dp->dad_na_icount); 1459 1460 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1461 ia->ia6_flags |= IN6_IFF_DUPLICATED; 1462 1463 /* We are done with DAD, with duplicate address found. (failure) */ 1464 nd6_dad_stoptimer(dp); 1465 1466 ifp = ifa->ifa_ifp; 1467 log(LOG_ERR, "%s: DAD complete for %s - duplicate found\n", 1468 if_name(ifp), ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr)); 1469 log(LOG_ERR, "%s: manual intervention required\n", 1470 if_name(ifp)); 1471 1472 /* 1473 * If the address is a link-local address formed from an interface 1474 * identifier based on the hardware address which is supposed to be 1475 * uniquely assigned (e.g., EUI-64 for an Ethernet interface), IP 1476 * operation on the interface SHOULD be disabled. 1477 * [RFC 4862, Section 5.4.5] 1478 */ 1479 if (IN6_IS_ADDR_LINKLOCAL(&ia->ia_addr.sin6_addr)) { 1480 struct in6_addr in6; 1481 1482 /* 1483 * To avoid over-reaction, we only apply this logic when we are 1484 * very sure that hardware addresses are supposed to be unique. 1485 */ 1486 switch (ifp->if_type) { 1487 case IFT_ETHER: 1488 case IFT_FDDI: 1489 case IFT_ATM: 1490 case IFT_IEEE1394: 1491#ifdef IFT_IEEE80211 1492 case IFT_IEEE80211: 1493#endif 1494 case IFT_INFINIBAND: 1495 in6 = ia->ia_addr.sin6_addr; 1496 if (in6_get_hw_ifid(ifp, &in6) == 0 && 1497 IN6_ARE_ADDR_EQUAL(&ia->ia_addr.sin6_addr, &in6)) { 1498 ND_IFINFO(ifp)->flags |= ND6_IFF_IFDISABLED; 1499 log(LOG_ERR, "%s: possible hardware address " 1500 "duplication detected, disable IPv6\n", 1501 if_name(ifp)); 1502 } 1503 break; 1504 } 1505 } 1506 1507 DADQ_WLOCK(); 1508 TAILQ_REMOVE(&V_dadq, (struct dadq *)dp, dad_list); 1509 DADQ_WUNLOCK(); 1510 free(dp, M_IP6NDP); 1511 dp = NULL; 1512 ifa_free(ifa); 1513} 1514 1515static void 1516nd6_dad_ns_output(struct dadq *dp, struct ifaddr *ifa) 1517{ 1518 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1519 struct ifnet *ifp = ifa->ifa_ifp; 1520 1521 dp->dad_ns_tcount++; 1522 if ((ifp->if_flags & IFF_UP) == 0) { 1523 return; 1524 } 1525 if ((ifp->if_drv_flags & IFF_DRV_RUNNING) == 0) { 1526 return; 1527 } 1528 1529 dp->dad_ns_ocount++; 1530 nd6_ns_output(ifp, NULL, &ia->ia_addr.sin6_addr, NULL, 1); 1531} 1532 1533static void 1534nd6_dad_ns_input(struct ifaddr *ifa) 1535{ 1536 struct in6_ifaddr *ia; 1537 struct ifnet *ifp; 1538 const struct in6_addr *taddr6; 1539 struct dadq *dp; 1540 int duplicate; 1541 1542 if (ifa == NULL) 1543 panic("ifa == NULL in nd6_dad_ns_input"); 1544 1545 ia = (struct in6_ifaddr *)ifa; 1546 ifp = ifa->ifa_ifp; 1547 taddr6 = &ia->ia_addr.sin6_addr; 1548 duplicate = 0; 1549 dp = nd6_dad_find(ifa); 1550 1551 /* Quickhack - completely ignore DAD NS packets */ 1552 if (V_dad_ignore_ns) { 1553 char ip6buf[INET6_ADDRSTRLEN]; 1554 nd6log((LOG_INFO, 1555 "nd6_dad_ns_input: ignoring DAD NS packet for " 1556 "address %s(%s)\n", ip6_sprintf(ip6buf, taddr6), 1557 if_name(ifa->ifa_ifp))); 1558 return; 1559 } 1560 1561 /* 1562 * if I'm yet to start DAD, someone else started using this address 1563 * first. I have a duplicate and you win. 1564 */ 1565 if (dp == NULL || dp->dad_ns_ocount == 0) 1566 duplicate++; 1567 1568 /* XXX more checks for loopback situation - see nd6_dad_timer too */ 1569 1570 if (duplicate) { 1571 dp = NULL; /* will be freed in nd6_dad_duplicated() */ 1572 nd6_dad_duplicated(ifa); 1573 } else { 1574 /* 1575 * not sure if I got a duplicate. 1576 * increment ns count and see what happens. 1577 */ 1578 if (dp) 1579 dp->dad_ns_icount++; 1580 } 1581} 1582 1583static void 1584nd6_dad_na_input(struct ifaddr *ifa) 1585{ 1586 struct dadq *dp; 1587 1588 if (ifa == NULL) 1589 panic("ifa == NULL in nd6_dad_na_input"); 1590 1591 dp = nd6_dad_find(ifa); 1592 if (dp) 1593 dp->dad_na_icount++; 1594 1595 /* remove the address. */ 1596 nd6_dad_duplicated(ifa); 1597} 1598