Now available: The Design and Implementation of the FreeBSD Operating System (Second Edition)
[ source navigation ] [ diff markup ] [ identifier search ] [ freetext search ] [ file search ] [ list types ] [ track identifier ]
FreeBSD/Linux Kernel Cross Reference
sys/netinet6/nd6_nbr.c
Version:
- FREEBSD - FREEBSD-13-STABLE - FREEBSD-13-0 - FREEBSD-12-STABLE - FREEBSD-12-0 - FREEBSD-11-STABLE - FREEBSD-11-0 - FREEBSD-10-STABLE - FREEBSD-10-0 - FREEBSD-9-STABLE - FREEBSD-9-0 - FREEBSD-8-STABLE - FREEBSD-8-0 - FREEBSD-7-STABLE - FREEBSD-7-0 - FREEBSD-6-STABLE - FREEBSD-6-0 - FREEBSD-5-STABLE - FREEBSD-5-0 - FREEBSD-4-STABLE - FREEBSD-3-STABLE - FREEBSD22 - l41 - OPENBSD - linux-2.6 - MK84 - PLAN9 - xnu-8792
SearchContext: - none - 3 - 10
SearchContext: - none - 3 - 10
1 /*- 2 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project. 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. Neither the name of the project nor the names of its contributors 14 * may be used to endorse or promote products derived from this software 15 * without specific prior written permission. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE 21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * SUCH DAMAGE. 28 * 29 * $KAME: nd6_nbr.c,v 1.86 2002/01/21 02:33:04 jinmei Exp $ 30 */ 31 32 #include <sys/cdefs.h> 33 __FBSDID("$FreeBSD: releng/8.4/sys/netinet6/nd6_nbr.c 233047 2012-03-16 21:28:29Z jhb $"); 34 35 #include "opt_inet.h" 36 #include "opt_inet6.h" 37 #include "opt_ipsec.h" 38 #include "opt_mpath.h" 39 40 #include <sys/param.h> 41 #include <sys/systm.h> 42 #include <sys/malloc.h> 43 #include <sys/lock.h> 44 #include <sys/rwlock.h> 45 #include <sys/mbuf.h> 46 #include <sys/socket.h> 47 #include <sys/sockio.h> 48 #include <sys/time.h> 49 #include <sys/kernel.h> 50 #include <sys/errno.h> 51 #include <sys/syslog.h> 52 #include <sys/queue.h> 53 #include <sys/callout.h> 54 55 #include <net/if.h> 56 #include <net/if_types.h> 57 #include <net/if_dl.h> 58 #include <net/if_var.h> 59 #include <net/route.h> 60 #ifdef RADIX_MPATH 61 #include <net/radix_mpath.h> 62 #endif 63 64 #include <netinet/in.h> 65 #include <netinet/in_var.h> 66 #include <net/if_llatbl.h> 67 #define L3_ADDR_SIN6(le) ((struct sockaddr_in6 *) L3_ADDR(le)) 68 #include <netinet6/in6_var.h> 69 #include <netinet6/in6_ifattach.h> 70 #include <netinet/ip6.h> 71 #include <netinet6/ip6_var.h> 72 #include <netinet6/scope6_var.h> 73 #include <netinet6/nd6.h> 74 #include <netinet/icmp6.h> 75 #include <netinet/ip_carp.h> 76 77 #define SDL(s) ((struct sockaddr_dl *)s) 78 79 struct dadq; 80 static struct dadq *nd6_dad_find(struct ifaddr *); 81 static void nd6_dad_starttimer(struct dadq *, int); 82 static void nd6_dad_stoptimer(struct dadq *); 83 static void nd6_dad_timer(struct dadq *); 84 static void nd6_dad_ns_output(struct dadq *, struct ifaddr *); 85 static void nd6_dad_ns_input(struct ifaddr *); 86 static void nd6_dad_na_input(struct ifaddr *); 87 static void nd6_na_output_fib(struct ifnet *, const struct in6_addr *, 88 const struct in6_addr *, u_long, int, struct sockaddr *, u_int); 89 90 VNET_DEFINE(int, dad_ignore_ns) = 0; /* ignore NS in DAD - specwise incorrect*/ 91 VNET_DEFINE(int, dad_maxtry) = 15; /* max # of *tries* to transmit DAD packet */ 92 #define V_dad_ignore_ns VNET(dad_ignore_ns) 93 #define V_dad_maxtry VNET(dad_maxtry) 94 95 /* 96 * Input a Neighbor Solicitation Message. 97 * 98 * Based on RFC 2461 99 * Based on RFC 2462 (duplicate address detection) 100 */ 101 void 102 nd6_ns_input(struct mbuf *m, int off, int icmp6len) 103 { 104 struct ifnet *ifp = m->m_pkthdr.rcvif; 105 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 106 struct nd_neighbor_solicit *nd_ns; 107 struct in6_addr saddr6 = ip6->ip6_src; 108 struct in6_addr daddr6 = ip6->ip6_dst; 109 struct in6_addr taddr6; 110 struct in6_addr myaddr6; 111 char *lladdr = NULL; 112 struct ifaddr *ifa = NULL; 113 int lladdrlen = 0; 114 int anycast = 0, proxy = 0, tentative = 0; 115 int tlladdr; 116 union nd_opts ndopts; 117 struct sockaddr_dl proxydl; 118 char ip6bufs[INET6_ADDRSTRLEN], ip6bufd[INET6_ADDRSTRLEN]; 119 120 #ifndef PULLDOWN_TEST 121 IP6_EXTHDR_CHECK(m, off, icmp6len,); 122 nd_ns = (struct nd_neighbor_solicit *)((caddr_t)ip6 + off); 123 #else 124 IP6_EXTHDR_GET(nd_ns, struct nd_neighbor_solicit *, m, off, icmp6len); 125 if (nd_ns == NULL) { 126 ICMP6STAT_INC(icp6s_tooshort); 127 return; 128 } 129 #endif 130 ip6 = mtod(m, struct ip6_hdr *); /* adjust pointer for safety */ 131 taddr6 = nd_ns->nd_ns_target; 132 if (in6_setscope(&taddr6, ifp, NULL) != 0) 133 goto bad; 134 135 if (ip6->ip6_hlim != 255) { 136 nd6log((LOG_ERR, 137 "nd6_ns_input: invalid hlim (%d) from %s to %s on %s\n", 138 ip6->ip6_hlim, ip6_sprintf(ip6bufs, &ip6->ip6_src), 139 ip6_sprintf(ip6bufd, &ip6->ip6_dst), if_name(ifp))); 140 goto bad; 141 } 142 143 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) { 144 /* dst has to be a solicited node multicast address. */ 145 if (daddr6.s6_addr16[0] == IPV6_ADDR_INT16_MLL && 146 /* don't check ifindex portion */ 147 daddr6.s6_addr32[1] == 0 && 148 daddr6.s6_addr32[2] == IPV6_ADDR_INT32_ONE && 149 daddr6.s6_addr8[12] == 0xff) { 150 ; /* good */ 151 } else { 152 nd6log((LOG_INFO, "nd6_ns_input: bad DAD packet " 153 "(wrong ip6 dst)\n")); 154 goto bad; 155 } 156 } else if (!V_nd6_onlink_ns_rfc4861) { 157 struct sockaddr_in6 src_sa6; 158 159 /* 160 * According to recent IETF discussions, it is not a good idea 161 * to accept a NS from an address which would not be deemed 162 * to be a neighbor otherwise. This point is expected to be 163 * clarified in future revisions of the specification. 164 */ 165 bzero(&src_sa6, sizeof(src_sa6)); 166 src_sa6.sin6_family = AF_INET6; 167 src_sa6.sin6_len = sizeof(src_sa6); 168 src_sa6.sin6_addr = saddr6; 169 if (nd6_is_addr_neighbor(&src_sa6, ifp) == 0) { 170 nd6log((LOG_INFO, "nd6_ns_input: " 171 "NS packet from non-neighbor\n")); 172 goto bad; 173 } 174 } 175 176 if (IN6_IS_ADDR_MULTICAST(&taddr6)) { 177 nd6log((LOG_INFO, "nd6_ns_input: bad NS target (multicast)\n")); 178 goto bad; 179 } 180 181 icmp6len -= sizeof(*nd_ns); 182 nd6_option_init(nd_ns + 1, icmp6len, &ndopts); 183 if (nd6_options(&ndopts) < 0) { 184 nd6log((LOG_INFO, 185 "nd6_ns_input: invalid ND option, ignored\n")); 186 /* nd6_options have incremented stats */ 187 goto freeit; 188 } 189 190 if (ndopts.nd_opts_src_lladdr) { 191 lladdr = (char *)(ndopts.nd_opts_src_lladdr + 1); 192 lladdrlen = ndopts.nd_opts_src_lladdr->nd_opt_len << 3; 193 } 194 195 if (IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_src) && lladdr) { 196 nd6log((LOG_INFO, "nd6_ns_input: bad DAD packet " 197 "(link-layer address option)\n")); 198 goto bad; 199 } 200 201 /* 202 * Attaching target link-layer address to the NA? 203 * (RFC 2461 7.2.4) 204 * 205 * NS IP dst is unicast/anycast MUST NOT add 206 * NS IP dst is solicited-node multicast MUST add 207 * 208 * In implementation, we add target link-layer address by default. 209 * We do not add one in MUST NOT cases. 210 */ 211 if (!IN6_IS_ADDR_MULTICAST(&daddr6)) 212 tlladdr = 0; 213 else 214 tlladdr = 1; 215 216 /* 217 * Target address (taddr6) must be either: 218 * (1) Valid unicast/anycast address for my receiving interface, 219 * (2) Unicast address for which I'm offering proxy service, or 220 * (3) "tentative" address on which DAD is being performed. 221 */ 222 /* (1) and (3) check. */ 223 if (ifp->if_carp) 224 ifa = (*carp_iamatch6_p)(ifp, &taddr6); 225 if (ifa == NULL) 226 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &taddr6); 227 228 /* (2) check. */ 229 if (ifa == NULL) { 230 struct rtentry *rt; 231 struct sockaddr_in6 tsin6; 232 int need_proxy; 233 #ifdef RADIX_MPATH 234 struct route_in6 ro; 235 #endif 236 237 bzero(&tsin6, sizeof tsin6); 238 tsin6.sin6_len = sizeof(struct sockaddr_in6); 239 tsin6.sin6_family = AF_INET6; 240 tsin6.sin6_addr = taddr6; 241 242 /* Always use the default FIB. */ 243 #ifdef RADIX_MPATH 244 bzero(&ro, sizeof(ro)); 245 ro.ro_dst = tsin6; 246 rtalloc_mpath_fib((struct route *)&ro, RTF_ANNOUNCE, 247 RT_DEFAULT_FIB); 248 rt = ro.ro_rt; 249 #else 250 rt = in6_rtalloc1((struct sockaddr *)&tsin6, 0, 0, 251 RT_DEFAULT_FIB); 252 #endif 253 need_proxy = (rt && (rt->rt_flags & RTF_ANNOUNCE) != 0 && 254 rt->rt_gateway->sa_family == AF_LINK); 255 if (rt != NULL) { 256 /* 257 * Make a copy while we can be sure that rt_gateway 258 * is still stable before unlocking to avoid lock 259 * order problems. proxydl will only be used if 260 * proxy will be set in the next block. 261 */ 262 if (need_proxy) 263 proxydl = *SDL(rt->rt_gateway); 264 RTFREE_LOCKED(rt); 265 } 266 if (need_proxy) { 267 /* 268 * proxy NDP for single entry 269 */ 270 ifa = (struct ifaddr *)in6ifa_ifpforlinklocal(ifp, 271 IN6_IFF_NOTREADY|IN6_IFF_ANYCAST); 272 if (ifa) 273 proxy = 1; 274 } 275 } 276 if (ifa == NULL) { 277 /* 278 * We've got an NS packet, and we don't have that adddress 279 * assigned for us. We MUST silently ignore it. 280 * See RFC2461 7.2.3. 281 */ 282 goto freeit; 283 } 284 myaddr6 = *IFA_IN6(ifa); 285 anycast = ((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_ANYCAST; 286 tentative = ((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_TENTATIVE; 287 if (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_DUPLICATED) 288 goto freeit; 289 290 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) { 291 nd6log((LOG_INFO, "nd6_ns_input: lladdrlen mismatch for %s " 292 "(if %d, NS packet %d)\n", 293 ip6_sprintf(ip6bufs, &taddr6), 294 ifp->if_addrlen, lladdrlen - 2)); 295 goto bad; 296 } 297 298 if (IN6_ARE_ADDR_EQUAL(&myaddr6, &saddr6)) { 299 nd6log((LOG_INFO, "nd6_ns_input: duplicate IP6 address %s\n", 300 ip6_sprintf(ip6bufs, &saddr6))); 301 goto freeit; 302 } 303 304 /* 305 * We have neighbor solicitation packet, with target address equals to 306 * one of my tentative address. 307 * 308 * src addr how to process? 309 * --- --- 310 * multicast of course, invalid (rejected in ip6_input) 311 * unicast somebody is doing address resolution -> ignore 312 * unspec dup address detection 313 * 314 * The processing is defined in RFC 2462. 315 */ 316 if (tentative) { 317 /* 318 * If source address is unspecified address, it is for 319 * duplicate address detection. 320 * 321 * If not, the packet is for addess resolution; 322 * silently ignore it. 323 */ 324 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) 325 nd6_dad_ns_input(ifa); 326 327 goto freeit; 328 } 329 330 /* 331 * If the source address is unspecified address, entries must not 332 * be created or updated. 333 * It looks that sender is performing DAD. Output NA toward 334 * all-node multicast address, to tell the sender that I'm using 335 * the address. 336 * S bit ("solicited") must be zero. 337 */ 338 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) { 339 struct in6_addr in6_all; 340 341 in6_all = in6addr_linklocal_allnodes; 342 if (in6_setscope(&in6_all, ifp, NULL) != 0) 343 goto bad; 344 nd6_na_output_fib(ifp, &in6_all, &taddr6, 345 ((anycast || proxy || !tlladdr) ? 0 : ND_NA_FLAG_OVERRIDE) | 346 (V_ip6_forwarding ? ND_NA_FLAG_ROUTER : 0), 347 tlladdr, proxy ? (struct sockaddr *)&proxydl : NULL, 348 M_GETFIB(m)); 349 goto freeit; 350 } 351 352 nd6_cache_lladdr(ifp, &saddr6, lladdr, lladdrlen, 353 ND_NEIGHBOR_SOLICIT, 0); 354 355 nd6_na_output_fib(ifp, &saddr6, &taddr6, 356 ((anycast || proxy || !tlladdr) ? 0 : ND_NA_FLAG_OVERRIDE) | 357 (V_ip6_forwarding ? ND_NA_FLAG_ROUTER : 0) | ND_NA_FLAG_SOLICITED, 358 tlladdr, proxy ? (struct sockaddr *)&proxydl : NULL, M_GETFIB(m)); 359 freeit: 360 if (ifa != NULL) 361 ifa_free(ifa); 362 m_freem(m); 363 return; 364 365 bad: 366 nd6log((LOG_ERR, "nd6_ns_input: src=%s\n", 367 ip6_sprintf(ip6bufs, &saddr6))); 368 nd6log((LOG_ERR, "nd6_ns_input: dst=%s\n", 369 ip6_sprintf(ip6bufs, &daddr6))); 370 nd6log((LOG_ERR, "nd6_ns_input: tgt=%s\n", 371 ip6_sprintf(ip6bufs, &taddr6))); 372 ICMP6STAT_INC(icp6s_badns); 373 if (ifa != NULL) 374 ifa_free(ifa); 375 m_freem(m); 376 } 377 378 /* 379 * Output a Neighbor Solicitation Message. Caller specifies: 380 * - ICMP6 header source IP6 address 381 * - ND6 header target IP6 address 382 * - ND6 header source datalink address 383 * 384 * Based on RFC 2461 385 * Based on RFC 2462 (duplicate address detection) 386 * 387 * ln - for source address determination 388 * dad - duplicate address detection 389 */ 390 void 391 nd6_ns_output(struct ifnet *ifp, const struct in6_addr *daddr6, 392 const struct in6_addr *taddr6, struct llentry *ln, int dad) 393 { 394 struct mbuf *m; 395 struct ip6_hdr *ip6; 396 struct nd_neighbor_solicit *nd_ns; 397 struct ip6_moptions im6o; 398 int icmp6len; 399 int maxlen; 400 caddr_t mac; 401 struct route_in6 ro; 402 403 if (IN6_IS_ADDR_MULTICAST(taddr6)) 404 return; 405 406 /* estimate the size of message */ 407 maxlen = sizeof(*ip6) + sizeof(*nd_ns); 408 maxlen += (sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7; 409 if (max_linkhdr + maxlen >= MCLBYTES) { 410 #ifdef DIAGNOSTIC 411 printf("nd6_ns_output: max_linkhdr + maxlen >= MCLBYTES " 412 "(%d + %d > %d)\n", max_linkhdr, maxlen, MCLBYTES); 413 #endif 414 return; 415 } 416 417 MGETHDR(m, M_DONTWAIT, MT_DATA); 418 if (m && max_linkhdr + maxlen >= MHLEN) { 419 MCLGET(m, M_DONTWAIT); 420 if ((m->m_flags & M_EXT) == 0) { 421 m_free(m); 422 m = NULL; 423 } 424 } 425 if (m == NULL) 426 return; 427 m->m_pkthdr.rcvif = NULL; 428 429 bzero(&ro, sizeof(ro)); 430 431 if (daddr6 == NULL || IN6_IS_ADDR_MULTICAST(daddr6)) { 432 m->m_flags |= M_MCAST; 433 im6o.im6o_multicast_ifp = ifp; 434 im6o.im6o_multicast_hlim = 255; 435 im6o.im6o_multicast_loop = 0; 436 } 437 438 icmp6len = sizeof(*nd_ns); 439 m->m_pkthdr.len = m->m_len = sizeof(*ip6) + icmp6len; 440 m->m_data += max_linkhdr; /* or MH_ALIGN() equivalent? */ 441 442 /* fill neighbor solicitation packet */ 443 ip6 = mtod(m, struct ip6_hdr *); 444 ip6->ip6_flow = 0; 445 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 446 ip6->ip6_vfc |= IPV6_VERSION; 447 /* ip6->ip6_plen will be set later */ 448 ip6->ip6_nxt = IPPROTO_ICMPV6; 449 ip6->ip6_hlim = 255; 450 if (daddr6) 451 ip6->ip6_dst = *daddr6; 452 else { 453 ip6->ip6_dst.s6_addr16[0] = IPV6_ADDR_INT16_MLL; 454 ip6->ip6_dst.s6_addr16[1] = 0; 455 ip6->ip6_dst.s6_addr32[1] = 0; 456 ip6->ip6_dst.s6_addr32[2] = IPV6_ADDR_INT32_ONE; 457 ip6->ip6_dst.s6_addr32[3] = taddr6->s6_addr32[3]; 458 ip6->ip6_dst.s6_addr8[12] = 0xff; 459 if (in6_setscope(&ip6->ip6_dst, ifp, NULL) != 0) 460 goto bad; 461 } 462 if (!dad) { 463 struct ifaddr *ifa; 464 465 /* 466 * RFC2461 7.2.2: 467 * "If the source address of the packet prompting the 468 * solicitation is the same as one of the addresses assigned 469 * to the outgoing interface, that address SHOULD be placed 470 * in the IP Source Address of the outgoing solicitation. 471 * Otherwise, any one of the addresses assigned to the 472 * interface should be used." 473 * 474 * We use the source address for the prompting packet 475 * (saddr6), if: 476 * - saddr6 is given from the caller (by giving "ln"), and 477 * - saddr6 belongs to the outgoing interface. 478 * Otherwise, we perform the source address selection as usual. 479 */ 480 struct in6_addr *hsrc; 481 482 hsrc = NULL; 483 if (ln != NULL) { 484 LLE_RLOCK(ln); 485 if (ln->la_hold != NULL) { 486 struct ip6_hdr *hip6; /* hold ip6 */ 487 488 /* 489 * assuming every packet in la_hold has the same IP 490 * header 491 */ 492 hip6 = mtod(ln->la_hold, struct ip6_hdr *); 493 /* XXX pullup? */ 494 if (sizeof(*hip6) < ln->la_hold->m_len) { 495 ip6->ip6_src = hip6->ip6_src; 496 hsrc = &hip6->ip6_src; 497 } 498 } 499 LLE_RUNLOCK(ln); 500 } 501 if (hsrc && (ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, 502 hsrc)) != NULL) { 503 /* ip6_src set already. */ 504 ifa_free(ifa); 505 } else { 506 int error; 507 struct sockaddr_in6 dst_sa; 508 struct in6_addr src_in; 509 struct ifnet *oifp; 510 511 bzero(&dst_sa, sizeof(dst_sa)); 512 dst_sa.sin6_family = AF_INET6; 513 dst_sa.sin6_len = sizeof(dst_sa); 514 dst_sa.sin6_addr = ip6->ip6_dst; 515 516 oifp = ifp; 517 error = in6_selectsrc(&dst_sa, NULL, 518 NULL, &ro, NULL, &oifp, &src_in); 519 if (error) { 520 char ip6buf[INET6_ADDRSTRLEN]; 521 nd6log((LOG_DEBUG, 522 "nd6_ns_output: source can't be " 523 "determined: dst=%s, error=%d\n", 524 ip6_sprintf(ip6buf, &dst_sa.sin6_addr), 525 error)); 526 goto bad; 527 } 528 ip6->ip6_src = src_in; 529 } 530 } else { 531 /* 532 * Source address for DAD packet must always be IPv6 533 * unspecified address. (0::0) 534 * We actually don't have to 0-clear the address (we did it 535 * above), but we do so here explicitly to make the intention 536 * clearer. 537 */ 538 bzero(&ip6->ip6_src, sizeof(ip6->ip6_src)); 539 } 540 nd_ns = (struct nd_neighbor_solicit *)(ip6 + 1); 541 nd_ns->nd_ns_type = ND_NEIGHBOR_SOLICIT; 542 nd_ns->nd_ns_code = 0; 543 nd_ns->nd_ns_reserved = 0; 544 nd_ns->nd_ns_target = *taddr6; 545 in6_clearscope(&nd_ns->nd_ns_target); /* XXX */ 546 547 /* 548 * Add source link-layer address option. 549 * 550 * spec implementation 551 * --- --- 552 * DAD packet MUST NOT do not add the option 553 * there's no link layer address: 554 * impossible do not add the option 555 * there's link layer address: 556 * Multicast NS MUST add one add the option 557 * Unicast NS SHOULD add one add the option 558 */ 559 if (!dad && (mac = nd6_ifptomac(ifp))) { 560 int optlen = sizeof(struct nd_opt_hdr) + ifp->if_addrlen; 561 struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)(nd_ns + 1); 562 /* 8 byte alignments... */ 563 optlen = (optlen + 7) & ~7; 564 565 m->m_pkthdr.len += optlen; 566 m->m_len += optlen; 567 icmp6len += optlen; 568 bzero((caddr_t)nd_opt, optlen); 569 nd_opt->nd_opt_type = ND_OPT_SOURCE_LINKADDR; 570 nd_opt->nd_opt_len = optlen >> 3; 571 bcopy(mac, (caddr_t)(nd_opt + 1), ifp->if_addrlen); 572 } 573 574 ip6->ip6_plen = htons((u_short)icmp6len); 575 nd_ns->nd_ns_cksum = 0; 576 nd_ns->nd_ns_cksum = 577 in6_cksum(m, IPPROTO_ICMPV6, sizeof(*ip6), icmp6len); 578 579 ip6_output(m, NULL, &ro, dad ? IPV6_UNSPECSRC : 0, &im6o, NULL, NULL); 580 icmp6_ifstat_inc(ifp, ifs6_out_msg); 581 icmp6_ifstat_inc(ifp, ifs6_out_neighborsolicit); 582 ICMP6STAT_INC(icp6s_outhist[ND_NEIGHBOR_SOLICIT]); 583 584 if (ro.ro_rt) { /* we don't cache this route. */ 585 RTFREE(ro.ro_rt); 586 } 587 return; 588 589 bad: 590 if (ro.ro_rt) { 591 RTFREE(ro.ro_rt); 592 } 593 m_freem(m); 594 return; 595 } 596 597 /* 598 * Neighbor advertisement input handling. 599 * 600 * Based on RFC 2461 601 * Based on RFC 2462 (duplicate address detection) 602 * 603 * the following items are not implemented yet: 604 * - proxy advertisement delay rule (RFC2461 7.2.8, last paragraph, SHOULD) 605 * - anycast advertisement delay rule (RFC2461 7.2.7, SHOULD) 606 */ 607 void 608 nd6_na_input(struct mbuf *m, int off, int icmp6len) 609 { 610 struct ifnet *ifp = m->m_pkthdr.rcvif; 611 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 612 struct nd_neighbor_advert *nd_na; 613 struct in6_addr daddr6 = ip6->ip6_dst; 614 struct in6_addr taddr6; 615 int flags; 616 int is_router; 617 int is_solicited; 618 int is_override; 619 char *lladdr = NULL; 620 int lladdrlen = 0; 621 int checklink = 0; 622 struct ifaddr *ifa; 623 struct llentry *ln = NULL; 624 union nd_opts ndopts; 625 struct mbuf *chain = NULL; 626 struct sockaddr_in6 sin6; 627 char ip6bufs[INET6_ADDRSTRLEN], ip6bufd[INET6_ADDRSTRLEN]; 628 629 if (ip6->ip6_hlim != 255) { 630 nd6log((LOG_ERR, 631 "nd6_na_input: invalid hlim (%d) from %s to %s on %s\n", 632 ip6->ip6_hlim, ip6_sprintf(ip6bufs, &ip6->ip6_src), 633 ip6_sprintf(ip6bufd, &ip6->ip6_dst), if_name(ifp))); 634 goto bad; 635 } 636 637 #ifndef PULLDOWN_TEST 638 IP6_EXTHDR_CHECK(m, off, icmp6len,); 639 nd_na = (struct nd_neighbor_advert *)((caddr_t)ip6 + off); 640 #else 641 IP6_EXTHDR_GET(nd_na, struct nd_neighbor_advert *, m, off, icmp6len); 642 if (nd_na == NULL) { 643 ICMP6STAT_INC(icp6s_tooshort); 644 return; 645 } 646 #endif 647 648 flags = nd_na->nd_na_flags_reserved; 649 is_router = ((flags & ND_NA_FLAG_ROUTER) != 0); 650 is_solicited = ((flags & ND_NA_FLAG_SOLICITED) != 0); 651 is_override = ((flags & ND_NA_FLAG_OVERRIDE) != 0); 652 653 taddr6 = nd_na->nd_na_target; 654 if (in6_setscope(&taddr6, ifp, NULL)) 655 goto bad; /* XXX: impossible */ 656 657 if (IN6_IS_ADDR_MULTICAST(&taddr6)) { 658 nd6log((LOG_ERR, 659 "nd6_na_input: invalid target address %s\n", 660 ip6_sprintf(ip6bufs, &taddr6))); 661 goto bad; 662 } 663 if (IN6_IS_ADDR_MULTICAST(&daddr6)) 664 if (is_solicited) { 665 nd6log((LOG_ERR, 666 "nd6_na_input: a solicited adv is multicasted\n")); 667 goto bad; 668 } 669 670 icmp6len -= sizeof(*nd_na); 671 nd6_option_init(nd_na + 1, icmp6len, &ndopts); 672 if (nd6_options(&ndopts) < 0) { 673 nd6log((LOG_INFO, 674 "nd6_na_input: invalid ND option, ignored\n")); 675 /* nd6_options have incremented stats */ 676 goto freeit; 677 } 678 679 if (ndopts.nd_opts_tgt_lladdr) { 680 lladdr = (char *)(ndopts.nd_opts_tgt_lladdr + 1); 681 lladdrlen = ndopts.nd_opts_tgt_lladdr->nd_opt_len << 3; 682 } 683 684 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &taddr6); 685 686 /* 687 * Target address matches one of my interface address. 688 * 689 * If my address is tentative, this means that there's somebody 690 * already using the same address as mine. This indicates DAD failure. 691 * This is defined in RFC 2462. 692 * 693 * Otherwise, process as defined in RFC 2461. 694 */ 695 if (ifa 696 && (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_TENTATIVE)) { 697 ifa_free(ifa); 698 nd6_dad_na_input(ifa); 699 goto freeit; 700 } 701 702 /* Just for safety, maybe unnecessary. */ 703 if (ifa) { 704 ifa_free(ifa); 705 log(LOG_ERR, 706 "nd6_na_input: duplicate IP6 address %s\n", 707 ip6_sprintf(ip6bufs, &taddr6)); 708 goto freeit; 709 } 710 711 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) { 712 nd6log((LOG_INFO, "nd6_na_input: lladdrlen mismatch for %s " 713 "(if %d, NA packet %d)\n", ip6_sprintf(ip6bufs, &taddr6), 714 ifp->if_addrlen, lladdrlen - 2)); 715 goto bad; 716 } 717 718 /* 719 * If no neighbor cache entry is found, NA SHOULD silently be 720 * discarded. 721 */ 722 IF_AFDATA_LOCK(ifp); 723 ln = nd6_lookup(&taddr6, LLE_EXCLUSIVE, ifp); 724 IF_AFDATA_UNLOCK(ifp); 725 if (ln == NULL) { 726 goto freeit; 727 } 728 729 if (ln->ln_state == ND6_LLINFO_INCOMPLETE) { 730 /* 731 * If the link-layer has address, and no lladdr option came, 732 * discard the packet. 733 */ 734 if (ifp->if_addrlen && lladdr == NULL) { 735 goto freeit; 736 } 737 738 /* 739 * Record link-layer address, and update the state. 740 */ 741 bcopy(lladdr, &ln->ll_addr, ifp->if_addrlen); 742 ln->la_flags |= LLE_VALID; 743 if (is_solicited) { 744 ln->ln_state = ND6_LLINFO_REACHABLE; 745 ln->ln_byhint = 0; 746 if (!ND6_LLINFO_PERMANENT(ln)) { 747 nd6_llinfo_settimer_locked(ln, 748 (long)ND_IFINFO(ln->lle_tbl->llt_ifp)->reachable * hz); 749 } 750 } else { 751 ln->ln_state = ND6_LLINFO_STALE; 752 nd6_llinfo_settimer_locked(ln, (long)V_nd6_gctimer * hz); 753 } 754 if ((ln->ln_router = is_router) != 0) { 755 /* 756 * This means a router's state has changed from 757 * non-reachable to probably reachable, and might 758 * affect the status of associated prefixes.. 759 */ 760 checklink = 1; 761 } 762 } else { 763 int llchange; 764 765 /* 766 * Check if the link-layer address has changed or not. 767 */ 768 if (lladdr == NULL) 769 llchange = 0; 770 else { 771 if (ln->la_flags & LLE_VALID) { 772 if (bcmp(lladdr, &ln->ll_addr, ifp->if_addrlen)) 773 llchange = 1; 774 else 775 llchange = 0; 776 } else 777 llchange = 1; 778 } 779 780 /* 781 * This is VERY complex. Look at it with care. 782 * 783 * override solicit lladdr llchange action 784 * (L: record lladdr) 785 * 786 * 0 0 n -- (2c) 787 * 0 0 y n (2b) L 788 * 0 0 y y (1) REACHABLE->STALE 789 * 0 1 n -- (2c) *->REACHABLE 790 * 0 1 y n (2b) L *->REACHABLE 791 * 0 1 y y (1) REACHABLE->STALE 792 * 1 0 n -- (2a) 793 * 1 0 y n (2a) L 794 * 1 0 y y (2a) L *->STALE 795 * 1 1 n -- (2a) *->REACHABLE 796 * 1 1 y n (2a) L *->REACHABLE 797 * 1 1 y y (2a) L *->REACHABLE 798 */ 799 if (!is_override && (lladdr != NULL && llchange)) { /* (1) */ 800 /* 801 * If state is REACHABLE, make it STALE. 802 * no other updates should be done. 803 */ 804 if (ln->ln_state == ND6_LLINFO_REACHABLE) { 805 ln->ln_state = ND6_LLINFO_STALE; 806 nd6_llinfo_settimer_locked(ln, (long)V_nd6_gctimer * hz); 807 } 808 goto freeit; 809 } else if (is_override /* (2a) */ 810 || (!is_override && (lladdr != NULL && !llchange)) /* (2b) */ 811 || lladdr == NULL) { /* (2c) */ 812 /* 813 * Update link-local address, if any. 814 */ 815 if (lladdr != NULL) { 816 bcopy(lladdr, &ln->ll_addr, ifp->if_addrlen); 817 ln->la_flags |= LLE_VALID; 818 } 819 820 /* 821 * If solicited, make the state REACHABLE. 822 * If not solicited and the link-layer address was 823 * changed, make it STALE. 824 */ 825 if (is_solicited) { 826 ln->ln_state = ND6_LLINFO_REACHABLE; 827 ln->ln_byhint = 0; 828 if (!ND6_LLINFO_PERMANENT(ln)) { 829 nd6_llinfo_settimer_locked(ln, 830 (long)ND_IFINFO(ifp)->reachable * hz); 831 } 832 } else { 833 if (lladdr != NULL && llchange) { 834 ln->ln_state = ND6_LLINFO_STALE; 835 nd6_llinfo_settimer_locked(ln, 836 (long)V_nd6_gctimer * hz); 837 } 838 } 839 } 840 841 if (ln->ln_router && !is_router) { 842 /* 843 * The peer dropped the router flag. 844 * Remove the sender from the Default Router List and 845 * update the Destination Cache entries. 846 */ 847 struct nd_defrouter *dr; 848 struct in6_addr *in6; 849 850 in6 = &L3_ADDR_SIN6(ln)->sin6_addr; 851 852 /* 853 * Lock to protect the default router list. 854 * XXX: this might be unnecessary, since this function 855 * is only called under the network software interrupt 856 * context. However, we keep it just for safety. 857 */ 858 dr = defrouter_lookup(in6, ln->lle_tbl->llt_ifp); 859 if (dr) 860 defrtrlist_del(dr); 861 else if (!V_ip6_forwarding) { 862 /* 863 * Even if the neighbor is not in the default 864 * router list, the neighbor may be used 865 * as a next hop for some destinations 866 * (e.g. redirect case). So we must 867 * call rt6_flush explicitly. 868 */ 869 rt6_flush(&ip6->ip6_src, ifp); 870 } 871 } 872 ln->ln_router = is_router; 873 } 874 /* XXX - QL 875 * Does this matter? 876 * rt->rt_flags &= ~RTF_REJECT; 877 */ 878 ln->la_asked = 0; 879 if (ln->la_hold) { 880 struct mbuf *m_hold, *m_hold_next; 881 882 /* 883 * reset the la_hold in advance, to explicitly 884 * prevent a la_hold lookup in nd6_output() 885 * (wouldn't happen, though...) 886 */ 887 for (m_hold = ln->la_hold, ln->la_hold = NULL; 888 m_hold; m_hold = m_hold_next) { 889 m_hold_next = m_hold->m_nextpkt; 890 m_hold->m_nextpkt = NULL; 891 /* 892 * we assume ifp is not a loopback here, so just set 893 * the 2nd argument as the 1st one. 894 */ 895 nd6_output_lle(ifp, ifp, m_hold, L3_ADDR_SIN6(ln), NULL, ln, &chain); 896 } 897 } 898 freeit: 899 if (ln != NULL) { 900 if (chain) 901 memcpy(&sin6, L3_ADDR_SIN6(ln), sizeof(sin6)); 902 LLE_WUNLOCK(ln); 903 904 if (chain) 905 nd6_output_flush(ifp, ifp, chain, &sin6, NULL); 906 } 907 if (checklink) 908 pfxlist_onlink_check(); 909 910 m_freem(m); 911 return; 912 913 bad: 914 if (ln != NULL) 915 LLE_WUNLOCK(ln); 916 917 ICMP6STAT_INC(icp6s_badna); 918 m_freem(m); 919 } 920 921 /* 922 * Neighbor advertisement output handling. 923 * 924 * Based on RFC 2461 925 * 926 * the following items are not implemented yet: 927 * - proxy advertisement delay rule (RFC2461 7.2.8, last paragraph, SHOULD) 928 * - anycast advertisement delay rule (RFC2461 7.2.7, SHOULD) 929 * 930 * tlladdr - 1 if include target link-layer address 931 * sdl0 - sockaddr_dl (= proxy NA) or NULL 932 */ 933 static void 934 nd6_na_output_fib(struct ifnet *ifp, const struct in6_addr *daddr6_0, 935 const struct in6_addr *taddr6, u_long flags, int tlladdr, 936 struct sockaddr *sdl0, u_int fibnum) 937 { 938 struct mbuf *m; 939 struct ifnet *oifp; 940 struct ip6_hdr *ip6; 941 struct nd_neighbor_advert *nd_na; 942 struct ip6_moptions im6o; 943 struct in6_addr src, daddr6; 944 struct sockaddr_in6 dst_sa; 945 int icmp6len, maxlen, error; 946 caddr_t mac = NULL; 947 struct route_in6 ro; 948 949 bzero(&ro, sizeof(ro)); 950 951 daddr6 = *daddr6_0; /* make a local copy for modification */ 952 953 /* estimate the size of message */ 954 maxlen = sizeof(*ip6) + sizeof(*nd_na); 955 maxlen += (sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7; 956 if (max_linkhdr + maxlen >= MCLBYTES) { 957 #ifdef DIAGNOSTIC 958 printf("nd6_na_output: max_linkhdr + maxlen >= MCLBYTES " 959 "(%d + %d > %d)\n", max_linkhdr, maxlen, MCLBYTES); 960 #endif 961 return; 962 } 963 964 MGETHDR(m, M_DONTWAIT, MT_DATA); 965 if (m && max_linkhdr + maxlen >= MHLEN) { 966 MCLGET(m, M_DONTWAIT); 967 if ((m->m_flags & M_EXT) == 0) { 968 m_free(m); 969 m = NULL; 970 } 971 } 972 if (m == NULL) 973 return; 974 m->m_pkthdr.rcvif = NULL; 975 M_SETFIB(m, fibnum); 976 977 if (IN6_IS_ADDR_MULTICAST(&daddr6)) { 978 m->m_flags |= M_MCAST; 979 im6o.im6o_multicast_ifp = ifp; 980 im6o.im6o_multicast_hlim = 255; 981 im6o.im6o_multicast_loop = 0; 982 } 983 984 icmp6len = sizeof(*nd_na); 985 m->m_pkthdr.len = m->m_len = sizeof(struct ip6_hdr) + icmp6len; 986 m->m_data += max_linkhdr; /* or MH_ALIGN() equivalent? */ 987 988 /* fill neighbor advertisement packet */ 989 ip6 = mtod(m, struct ip6_hdr *); 990 ip6->ip6_flow = 0; 991 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 992 ip6->ip6_vfc |= IPV6_VERSION; 993 ip6->ip6_nxt = IPPROTO_ICMPV6; 994 ip6->ip6_hlim = 255; 995 if (IN6_IS_ADDR_UNSPECIFIED(&daddr6)) { 996 /* reply to DAD */ 997 daddr6.s6_addr16[0] = IPV6_ADDR_INT16_MLL; 998 daddr6.s6_addr16[1] = 0; 999 daddr6.s6_addr32[1] = 0; 1000 daddr6.s6_addr32[2] = 0; 1001 daddr6.s6_addr32[3] = IPV6_ADDR_INT32_ONE; 1002 if (in6_setscope(&daddr6, ifp, NULL)) 1003 goto bad; 1004 1005 flags &= ~ND_NA_FLAG_SOLICITED; 1006 } 1007 ip6->ip6_dst = daddr6; 1008 bzero(&dst_sa, sizeof(struct sockaddr_in6)); 1009 dst_sa.sin6_family = AF_INET6; 1010 dst_sa.sin6_len = sizeof(struct sockaddr_in6); 1011 dst_sa.sin6_addr = daddr6; 1012 1013 /* 1014 * Select a source whose scope is the same as that of the dest. 1015 */ 1016 bcopy(&dst_sa, &ro.ro_dst, sizeof(dst_sa)); 1017 oifp = ifp; 1018 error = in6_selectsrc(&dst_sa, NULL, NULL, &ro, NULL, &oifp, &src); 1019 if (error) { 1020 char ip6buf[INET6_ADDRSTRLEN]; 1021 nd6log((LOG_DEBUG, "nd6_na_output: source can't be " 1022 "determined: dst=%s, error=%d\n", 1023 ip6_sprintf(ip6buf, &dst_sa.sin6_addr), error)); 1024 goto bad; 1025 } 1026 ip6->ip6_src = src; 1027 nd_na = (struct nd_neighbor_advert *)(ip6 + 1); 1028 nd_na->nd_na_type = ND_NEIGHBOR_ADVERT; 1029 nd_na->nd_na_code = 0; 1030 nd_na->nd_na_target = *taddr6; 1031 in6_clearscope(&nd_na->nd_na_target); /* XXX */ 1032 1033 /* 1034 * "tlladdr" indicates NS's condition for adding tlladdr or not. 1035 * see nd6_ns_input() for details. 1036 * Basically, if NS packet is sent to unicast/anycast addr, 1037 * target lladdr option SHOULD NOT be included. 1038 */ 1039 if (tlladdr) { 1040 /* 1041 * sdl0 != NULL indicates proxy NA. If we do proxy, use 1042 * lladdr in sdl0. If we are not proxying (sending NA for 1043 * my address) use lladdr configured for the interface. 1044 */ 1045 if (sdl0 == NULL) { 1046 if (ifp->if_carp) 1047 mac = (*carp_macmatch6_p)(ifp, m, taddr6); 1048 if (mac == NULL) 1049 mac = nd6_ifptomac(ifp); 1050 } else if (sdl0->sa_family == AF_LINK) { 1051 struct sockaddr_dl *sdl; 1052 sdl = (struct sockaddr_dl *)sdl0; 1053 if (sdl->sdl_alen == ifp->if_addrlen) 1054 mac = LLADDR(sdl); 1055 } 1056 } 1057 if (tlladdr && mac) { 1058 int optlen = sizeof(struct nd_opt_hdr) + ifp->if_addrlen; 1059 struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)(nd_na + 1); 1060 1061 /* roundup to 8 bytes alignment! */ 1062 optlen = (optlen + 7) & ~7; 1063 1064 m->m_pkthdr.len += optlen; 1065 m->m_len += optlen; 1066 icmp6len += optlen; 1067 bzero((caddr_t)nd_opt, optlen); 1068 nd_opt->nd_opt_type = ND_OPT_TARGET_LINKADDR; 1069 nd_opt->nd_opt_len = optlen >> 3; 1070 bcopy(mac, (caddr_t)(nd_opt + 1), ifp->if_addrlen); 1071 } else 1072 flags &= ~ND_NA_FLAG_OVERRIDE; 1073 1074 ip6->ip6_plen = htons((u_short)icmp6len); 1075 nd_na->nd_na_flags_reserved = flags; 1076 nd_na->nd_na_cksum = 0; 1077 nd_na->nd_na_cksum = 1078 in6_cksum(m, IPPROTO_ICMPV6, sizeof(struct ip6_hdr), icmp6len); 1079 1080 ip6_output(m, NULL, &ro, 0, &im6o, NULL, NULL); 1081 icmp6_ifstat_inc(ifp, ifs6_out_msg); 1082 icmp6_ifstat_inc(ifp, ifs6_out_neighboradvert); 1083 ICMP6STAT_INC(icp6s_outhist[ND_NEIGHBOR_ADVERT]); 1084 1085 if (ro.ro_rt) { /* we don't cache this route. */ 1086 RTFREE(ro.ro_rt); 1087 } 1088 return; 1089 1090 bad: 1091 if (ro.ro_rt) { 1092 RTFREE(ro.ro_rt); 1093 } 1094 m_freem(m); 1095 return; 1096 } 1097 1098 #ifndef BURN_BRIDGES 1099 void 1100 nd6_na_output(struct ifnet *ifp, const struct in6_addr *daddr6_0, 1101 const struct in6_addr *taddr6, u_long flags, int tlladdr, 1102 struct sockaddr *sdl0) 1103 { 1104 1105 nd6_na_output_fib(ifp, daddr6_0, taddr6, flags, tlladdr, sdl0, 1106 RT_DEFAULT_FIB); 1107 } 1108 #endif 1109 1110 caddr_t 1111 nd6_ifptomac(struct ifnet *ifp) 1112 { 1113 switch (ifp->if_type) { 1114 case IFT_ARCNET: 1115 case IFT_ETHER: 1116 case IFT_FDDI: 1117 case IFT_IEEE1394: 1118 #ifdef IFT_L2VLAN 1119 case IFT_L2VLAN: 1120 #endif 1121 #ifdef IFT_IEEE80211 1122 case IFT_IEEE80211: 1123 #endif 1124 #ifdef IFT_CARP 1125 case IFT_CARP: 1126 #endif 1127 case IFT_BRIDGE: 1128 case IFT_ISO88025: 1129 return IF_LLADDR(ifp); 1130 default: 1131 return NULL; 1132 } 1133 } 1134 1135 struct dadq { 1136 TAILQ_ENTRY(dadq) dad_list; 1137 struct ifaddr *dad_ifa; 1138 int dad_count; /* max NS to send */ 1139 int dad_ns_tcount; /* # of trials to send NS */ 1140 int dad_ns_ocount; /* NS sent so far */ 1141 int dad_ns_icount; 1142 int dad_na_icount; 1143 struct callout dad_timer_ch; 1144 struct vnet *dad_vnet; 1145 }; 1146 1147 static VNET_DEFINE(TAILQ_HEAD(, dadq), dadq); 1148 VNET_DEFINE(int, dad_init) = 0; 1149 #define V_dadq VNET(dadq) 1150 #define V_dad_init VNET(dad_init) 1151 1152 static struct dadq * 1153 nd6_dad_find(struct ifaddr *ifa) 1154 { 1155 struct dadq *dp; 1156 1157 TAILQ_FOREACH(dp, &V_dadq, dad_list) 1158 if (dp->dad_ifa == ifa) 1159 return (dp); 1160 1161 return (NULL); 1162 } 1163 1164 static void 1165 nd6_dad_starttimer(struct dadq *dp, int ticks) 1166 { 1167 1168 callout_reset(&dp->dad_timer_ch, ticks, 1169 (void (*)(void *))nd6_dad_timer, (void *)dp); 1170 } 1171 1172 static void 1173 nd6_dad_stoptimer(struct dadq *dp) 1174 { 1175 1176 callout_stop(&dp->dad_timer_ch); 1177 } 1178 1179 /* 1180 * Start Duplicate Address Detection (DAD) for specified interface address. 1181 */ 1182 void 1183 nd6_dad_start(struct ifaddr *ifa, int delay) 1184 { 1185 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1186 struct dadq *dp; 1187 char ip6buf[INET6_ADDRSTRLEN]; 1188 1189 if (!V_dad_init) { 1190 TAILQ_INIT(&V_dadq); 1191 V_dad_init++; 1192 } 1193 1194 /* 1195 * If we don't need DAD, don't do it. 1196 * There are several cases: 1197 * - DAD is disabled (ip6_dad_count == 0) 1198 * - the interface address is anycast 1199 */ 1200 if (!(ia->ia6_flags & IN6_IFF_TENTATIVE)) { 1201 log(LOG_DEBUG, 1202 "nd6_dad_start: called with non-tentative address " 1203 "%s(%s)\n", 1204 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr), 1205 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1206 return; 1207 } 1208 if (ia->ia6_flags & IN6_IFF_ANYCAST) { 1209 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1210 return; 1211 } 1212 if (!V_ip6_dad_count) { 1213 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1214 return; 1215 } 1216 if (ifa->ifa_ifp == NULL) 1217 panic("nd6_dad_start: ifa->ifa_ifp == NULL"); 1218 if (!(ifa->ifa_ifp->if_flags & IFF_UP)) { 1219 return; 1220 } 1221 if (nd6_dad_find(ifa) != NULL) { 1222 /* DAD already in progress */ 1223 return; 1224 } 1225 1226 dp = malloc(sizeof(*dp), M_IP6NDP, M_NOWAIT); 1227 if (dp == NULL) { 1228 log(LOG_ERR, "nd6_dad_start: memory allocation failed for " 1229 "%s(%s)\n", 1230 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr), 1231 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1232 return; 1233 } 1234 bzero(dp, sizeof(*dp)); 1235 callout_init(&dp->dad_timer_ch, 0); 1236 #ifdef VIMAGE 1237 dp->dad_vnet = curvnet; 1238 #endif 1239 TAILQ_INSERT_TAIL(&V_dadq, (struct dadq *)dp, dad_list); 1240 1241 nd6log((LOG_DEBUG, "%s: starting DAD for %s\n", if_name(ifa->ifa_ifp), 1242 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr))); 1243 1244 /* 1245 * Send NS packet for DAD, ip6_dad_count times. 1246 * Note that we must delay the first transmission, if this is the 1247 * first packet to be sent from the interface after interface 1248 * (re)initialization. 1249 */ 1250 dp->dad_ifa = ifa; 1251 ifa_ref(ifa); /* just for safety */ 1252 dp->dad_count = V_ip6_dad_count; 1253 dp->dad_ns_icount = dp->dad_na_icount = 0; 1254 dp->dad_ns_ocount = dp->dad_ns_tcount = 0; 1255 if (delay == 0) { 1256 nd6_dad_ns_output(dp, ifa); 1257 nd6_dad_starttimer(dp, 1258 (long)ND_IFINFO(ifa->ifa_ifp)->retrans * hz / 1000); 1259 } else { 1260 nd6_dad_starttimer(dp, delay); 1261 } 1262 } 1263 1264 /* 1265 * terminate DAD unconditionally. used for address removals. 1266 */ 1267 void 1268 nd6_dad_stop(struct ifaddr *ifa) 1269 { 1270 struct dadq *dp; 1271 1272 if (!V_dad_init) 1273 return; 1274 dp = nd6_dad_find(ifa); 1275 if (!dp) { 1276 /* DAD wasn't started yet */ 1277 return; 1278 } 1279 1280 nd6_dad_stoptimer(dp); 1281 1282 TAILQ_REMOVE(&V_dadq, (struct dadq *)dp, dad_list); 1283 free(dp, M_IP6NDP); 1284 dp = NULL; 1285 ifa_free(ifa); 1286 } 1287 1288 static void 1289 nd6_dad_timer(struct dadq *dp) 1290 { 1291 CURVNET_SET(dp->dad_vnet); 1292 int s; 1293 struct ifaddr *ifa = dp->dad_ifa; 1294 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1295 char ip6buf[INET6_ADDRSTRLEN]; 1296 1297 s = splnet(); /* XXX */ 1298 1299 /* Sanity check */ 1300 if (ia == NULL) { 1301 log(LOG_ERR, "nd6_dad_timer: called with null parameter\n"); 1302 goto done; 1303 } 1304 if (ia->ia6_flags & IN6_IFF_DUPLICATED) { 1305 log(LOG_ERR, "nd6_dad_timer: called with duplicated address " 1306 "%s(%s)\n", 1307 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr), 1308 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1309 goto done; 1310 } 1311 if ((ia->ia6_flags & IN6_IFF_TENTATIVE) == 0) { 1312 log(LOG_ERR, "nd6_dad_timer: called with non-tentative address " 1313 "%s(%s)\n", 1314 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr), 1315 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1316 goto done; 1317 } 1318 1319 /* timeouted with IFF_{RUNNING,UP} check */ 1320 if (dp->dad_ns_tcount > V_dad_maxtry) { 1321 nd6log((LOG_INFO, "%s: could not run DAD, driver problem?\n", 1322 if_name(ifa->ifa_ifp))); 1323 1324 TAILQ_REMOVE(&V_dadq, (struct dadq *)dp, dad_list); 1325 free(dp, M_IP6NDP); 1326 dp = NULL; 1327 ifa_free(ifa); 1328 goto done; 1329 } 1330 1331 /* Need more checks? */ 1332 if (dp->dad_ns_ocount < dp->dad_count) { 1333 /* 1334 * We have more NS to go. Send NS packet for DAD. 1335 */ 1336 nd6_dad_ns_output(dp, ifa); 1337 nd6_dad_starttimer(dp, 1338 (long)ND_IFINFO(ifa->ifa_ifp)->retrans * hz / 1000); 1339 } else { 1340 /* 1341 * We have transmitted sufficient number of DAD packets. 1342 * See what we've got. 1343 */ 1344 int duplicate; 1345 1346 duplicate = 0; 1347 1348 if (dp->dad_na_icount) { 1349 /* 1350 * the check is in nd6_dad_na_input(), 1351 * but just in case 1352 */ 1353 duplicate++; 1354 } 1355 1356 if (dp->dad_ns_icount) { 1357 /* We've seen NS, means DAD has failed. */ 1358 duplicate++; 1359 } 1360 1361 if (duplicate) { 1362 /* (*dp) will be freed in nd6_dad_duplicated() */ 1363 dp = NULL; 1364 nd6_dad_duplicated(ifa); 1365 } else { 1366 /* 1367 * We are done with DAD. No NA came, no NS came. 1368 * No duplicate address found. 1369 */ 1370 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1371 1372 nd6log((LOG_DEBUG, 1373 "%s: DAD complete for %s - no duplicates found\n", 1374 if_name(ifa->ifa_ifp), 1375 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr))); 1376 1377 TAILQ_REMOVE(&V_dadq, (struct dadq *)dp, dad_list); 1378 free(dp, M_IP6NDP); 1379 dp = NULL; 1380 ifa_free(ifa); 1381 } 1382 } 1383 1384 done: 1385 splx(s); 1386 CURVNET_RESTORE(); 1387 } 1388 1389 void 1390 nd6_dad_duplicated(struct ifaddr *ifa) 1391 { 1392 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1393 struct ifnet *ifp; 1394 struct dadq *dp; 1395 char ip6buf[INET6_ADDRSTRLEN]; 1396 1397 dp = nd6_dad_find(ifa); 1398 if (dp == NULL) { 1399 log(LOG_ERR, "nd6_dad_duplicated: DAD structure not found\n"); 1400 return; 1401 } 1402 1403 log(LOG_ERR, "%s: DAD detected duplicate IPv6 address %s: " 1404 "NS in/out=%d/%d, NA in=%d\n", 1405 if_name(ifa->ifa_ifp), ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr), 1406 dp->dad_ns_icount, dp->dad_ns_ocount, dp->dad_na_icount); 1407 1408 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1409 ia->ia6_flags |= IN6_IFF_DUPLICATED; 1410 1411 /* We are done with DAD, with duplicate address found. (failure) */ 1412 nd6_dad_stoptimer(dp); 1413 1414 ifp = ifa->ifa_ifp; 1415 log(LOG_ERR, "%s: DAD complete for %s - duplicate found\n", 1416 if_name(ifp), ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr)); 1417 log(LOG_ERR, "%s: manual intervention required\n", 1418 if_name(ifp)); 1419 1420 /* 1421 * If the address is a link-local address formed from an interface 1422 * identifier based on the hardware address which is supposed to be 1423 * uniquely assigned (e.g., EUI-64 for an Ethernet interface), IP 1424 * operation on the interface SHOULD be disabled. 1425 * [rfc2462bis-03 Section 5.4.5] 1426 */ 1427 if (IN6_IS_ADDR_LINKLOCAL(&ia->ia_addr.sin6_addr)) { 1428 struct in6_addr in6; 1429 1430 /* 1431 * To avoid over-reaction, we only apply this logic when we are 1432 * very sure that hardware addresses are supposed to be unique. 1433 */ 1434 switch (ifp->if_type) { 1435 case IFT_ETHER: 1436 case IFT_FDDI: 1437 case IFT_ATM: 1438 case IFT_IEEE1394: 1439 #ifdef IFT_IEEE80211 1440 case IFT_IEEE80211: 1441 #endif 1442 in6 = ia->ia_addr.sin6_addr; 1443 if (in6_get_hw_ifid(ifp, &in6) == 0 && 1444 IN6_ARE_ADDR_EQUAL(&ia->ia_addr.sin6_addr, &in6)) { 1445 ND_IFINFO(ifp)->flags |= ND6_IFF_IFDISABLED; 1446 log(LOG_ERR, "%s: possible hardware address " 1447 "duplication detected, disable IPv6\n", 1448 if_name(ifp)); 1449 } 1450 break; 1451 } 1452 } 1453 1454 TAILQ_REMOVE(&V_dadq, (struct dadq *)dp, dad_list); 1455 free(dp, M_IP6NDP); 1456 dp = NULL; 1457 ifa_free(ifa); 1458 } 1459 1460 static void 1461 nd6_dad_ns_output(struct dadq *dp, struct ifaddr *ifa) 1462 { 1463 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1464 struct ifnet *ifp = ifa->ifa_ifp; 1465 1466 dp->dad_ns_tcount++; 1467 if ((ifp->if_flags & IFF_UP) == 0) { 1468 return; 1469 } 1470 if ((ifp->if_drv_flags & IFF_DRV_RUNNING) == 0) { 1471 return; 1472 } 1473 1474 dp->dad_ns_ocount++; 1475 nd6_ns_output(ifp, NULL, &ia->ia_addr.sin6_addr, NULL, 1); 1476 } 1477 1478 static void 1479 nd6_dad_ns_input(struct ifaddr *ifa) 1480 { 1481 struct in6_ifaddr *ia; 1482 struct ifnet *ifp; 1483 const struct in6_addr *taddr6; 1484 struct dadq *dp; 1485 int duplicate; 1486 1487 if (ifa == NULL) 1488 panic("ifa == NULL in nd6_dad_ns_input"); 1489 1490 ia = (struct in6_ifaddr *)ifa; 1491 ifp = ifa->ifa_ifp; 1492 taddr6 = &ia->ia_addr.sin6_addr; 1493 duplicate = 0; 1494 dp = nd6_dad_find(ifa); 1495 1496 /* Quickhack - completely ignore DAD NS packets */ 1497 if (V_dad_ignore_ns) { 1498 char ip6buf[INET6_ADDRSTRLEN]; 1499 nd6log((LOG_INFO, 1500 "nd6_dad_ns_input: ignoring DAD NS packet for " 1501 "address %s(%s)\n", ip6_sprintf(ip6buf, taddr6), 1502 if_name(ifa->ifa_ifp))); 1503 return; 1504 } 1505 1506 /* 1507 * if I'm yet to start DAD, someone else started using this address 1508 * first. I have a duplicate and you win. 1509 */ 1510 if (dp == NULL || dp->dad_ns_ocount == 0) 1511 duplicate++; 1512 1513 /* XXX more checks for loopback situation - see nd6_dad_timer too */ 1514 1515 if (duplicate) { 1516 dp = NULL; /* will be freed in nd6_dad_duplicated() */ 1517 nd6_dad_duplicated(ifa); 1518 } else { 1519 /* 1520 * not sure if I got a duplicate. 1521 * increment ns count and see what happens. 1522 */ 1523 if (dp) 1524 dp->dad_ns_icount++; 1525 } 1526 } 1527 1528 static void 1529 nd6_dad_na_input(struct ifaddr *ifa) 1530 { 1531 struct dadq *dp; 1532 1533 if (ifa == NULL) 1534 panic("ifa == NULL in nd6_dad_na_input"); 1535 1536 dp = nd6_dad_find(ifa); 1537 if (dp) 1538 dp->dad_na_icount++; 1539 1540 /* remove the address. */ 1541 nd6_dad_duplicated(ifa); 1542 }
Cache object: 630d1363c494f65be79cf044b7a4abe8
[ source navigation ] [ diff markup ] [ identifier search ] [ freetext search ] [ file search ] [ list types ] [ track identifier ]