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("$FreeBSD$"); 34 35 #include "opt_inet.h" 36 #include "opt_inet6.h" 37 #include "opt_ipsec.h" 38 #include "opt_mpath.h" 39 40 #include <sys/param.h> 41 #include <sys/systm.h> 42 #include <sys/malloc.h> 43 #include <sys/lock.h> 44 #include <sys/rwlock.h> 45 #include <sys/mbuf.h> 46 #include <sys/socket.h> 47 #include <sys/sockio.h> 48 #include <sys/time.h> 49 #include <sys/kernel.h> 50 #include <sys/errno.h> 51 #include <sys/syslog.h> 52 #include <sys/queue.h> 53 #include <sys/callout.h> 54 55 #include <net/if.h> 56 #include <net/if_types.h> 57 #include <net/if_dl.h> 58 #include <net/if_var.h> 59 #include <net/route.h> 60 #ifdef RADIX_MPATH 61 #include <net/radix_mpath.h> 62 #endif 63 64 #include <netinet/in.h> 65 #include <netinet/in_var.h> 66 #include <net/if_llatbl.h> 67 #define L3_ADDR_SIN6(le) ((struct sockaddr_in6 *) L3_ADDR(le)) 68 #include <netinet6/in6_var.h> 69 #include <netinet6/in6_ifattach.h> 70 #include <netinet/ip6.h> 71 #include <netinet6/ip6_var.h> 72 #include <netinet6/scope6_var.h> 73 #include <netinet6/nd6.h> 74 #include <netinet/icmp6.h> 75 #include <netinet/ip_carp.h> 76 #include <netinet6/send.h> 77 78 #define SDL(s) ((struct sockaddr_dl *)s) 79 80 struct dadq; 81 static struct dadq *nd6_dad_find(struct ifaddr *); 82 static void nd6_dad_starttimer(struct dadq *, int); 83 static void nd6_dad_stoptimer(struct dadq *); 84 static void nd6_dad_timer(struct dadq *); 85 static void nd6_dad_ns_output(struct dadq *, struct ifaddr *); 86 static void nd6_dad_ns_input(struct ifaddr *); 87 static void nd6_dad_na_input(struct ifaddr *); 88 static void nd6_na_output_fib(struct ifnet *, const struct in6_addr *, 89 const struct in6_addr *, u_long, int, struct sockaddr *, u_int); 90 91 VNET_DEFINE(int, dad_ignore_ns) = 0; /* ignore NS in DAD - specwise incorrect*/ 92 VNET_DEFINE(int, dad_maxtry) = 15; /* max # of *tries* to transmit DAD packet */ 93 #define V_dad_ignore_ns VNET(dad_ignore_ns) 94 #define V_dad_maxtry VNET(dad_maxtry) 95 96 /* 97 * Input a Neighbor Solicitation Message. 98 * 99 * Based on RFC 2461 100 * Based on RFC 2462 (duplicate address detection) 101 */ 102 void 103 nd6_ns_input(struct mbuf *m, int off, int icmp6len) 104 { 105 struct ifnet *ifp = m->m_pkthdr.rcvif; 106 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 107 struct nd_neighbor_solicit *nd_ns; 108 struct in6_addr saddr6 = ip6->ip6_src; 109 struct in6_addr daddr6 = ip6->ip6_dst; 110 struct in6_addr taddr6; 111 struct in6_addr myaddr6; 112 char *lladdr = NULL; 113 struct ifaddr *ifa = NULL; 114 int lladdrlen = 0; 115 int anycast = 0, proxy = 0, tentative = 0; 116 int tlladdr; 117 int rflag; 118 union nd_opts ndopts; 119 struct sockaddr_dl proxydl; 120 char ip6bufs[INET6_ADDRSTRLEN], ip6bufd[INET6_ADDRSTRLEN]; 121 122 rflag = (V_ip6_forwarding) ? ND_NA_FLAG_ROUTER : 0; 123 if (ND_IFINFO(ifp)->flags & ND6_IFF_ACCEPT_RTADV && V_ip6_norbit_raif) 124 rflag = 0; 125 #ifndef PULLDOWN_TEST 126 IP6_EXTHDR_CHECK(m, off, icmp6len,); 127 nd_ns = (struct nd_neighbor_solicit *)((caddr_t)ip6 + off); 128 #else 129 IP6_EXTHDR_GET(nd_ns, struct nd_neighbor_solicit *, m, off, icmp6len); 130 if (nd_ns == NULL) { 131 ICMP6STAT_INC(icp6s_tooshort); 132 return; 133 } 134 #endif 135 ip6 = mtod(m, struct ip6_hdr *); /* adjust pointer for safety */ 136 taddr6 = nd_ns->nd_ns_target; 137 if (in6_setscope(&taddr6, ifp, NULL) != 0) 138 goto bad; 139 140 if (ip6->ip6_hlim != 255) { 141 nd6log((LOG_ERR, 142 "nd6_ns_input: invalid hlim (%d) from %s to %s on %s\n", 143 ip6->ip6_hlim, ip6_sprintf(ip6bufs, &ip6->ip6_src), 144 ip6_sprintf(ip6bufd, &ip6->ip6_dst), if_name(ifp))); 145 goto bad; 146 } 147 148 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) { 149 /* dst has to be a solicited node multicast address. */ 150 if (daddr6.s6_addr16[0] == IPV6_ADDR_INT16_MLL && 151 /* don't check ifindex portion */ 152 daddr6.s6_addr32[1] == 0 && 153 daddr6.s6_addr32[2] == IPV6_ADDR_INT32_ONE && 154 daddr6.s6_addr8[12] == 0xff) { 155 ; /* good */ 156 } else { 157 nd6log((LOG_INFO, "nd6_ns_input: bad DAD packet " 158 "(wrong ip6 dst)\n")); 159 goto bad; 160 } 161 } else if (!V_nd6_onlink_ns_rfc4861) { 162 struct sockaddr_in6 src_sa6; 163 164 /* 165 * According to recent IETF discussions, it is not a good idea 166 * to accept a NS from an address which would not be deemed 167 * to be a neighbor otherwise. This point is expected to be 168 * clarified in future revisions of the specification. 169 */ 170 bzero(&src_sa6, sizeof(src_sa6)); 171 src_sa6.sin6_family = AF_INET6; 172 src_sa6.sin6_len = sizeof(src_sa6); 173 src_sa6.sin6_addr = saddr6; 174 if (nd6_is_addr_neighbor(&src_sa6, ifp) == 0) { 175 nd6log((LOG_INFO, "nd6_ns_input: " 176 "NS packet from non-neighbor\n")); 177 goto bad; 178 } 179 } 180 181 if (IN6_IS_ADDR_MULTICAST(&taddr6)) { 182 nd6log((LOG_INFO, "nd6_ns_input: bad NS target (multicast)\n")); 183 goto bad; 184 } 185 186 icmp6len -= sizeof(*nd_ns); 187 nd6_option_init(nd_ns + 1, icmp6len, &ndopts); 188 if (nd6_options(&ndopts) < 0) { 189 nd6log((LOG_INFO, 190 "nd6_ns_input: invalid ND option, ignored\n")); 191 /* nd6_options have incremented stats */ 192 goto freeit; 193 } 194 195 if (ndopts.nd_opts_src_lladdr) { 196 lladdr = (char *)(ndopts.nd_opts_src_lladdr + 1); 197 lladdrlen = ndopts.nd_opts_src_lladdr->nd_opt_len << 3; 198 } 199 200 if (IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_src) && lladdr) { 201 nd6log((LOG_INFO, "nd6_ns_input: bad DAD packet " 202 "(link-layer address option)\n")); 203 goto bad; 204 } 205 206 /* 207 * Attaching target link-layer address to the NA? 208 * (RFC 2461 7.2.4) 209 * 210 * NS IP dst is unicast/anycast MUST NOT add 211 * NS IP dst is solicited-node multicast MUST add 212 * 213 * In implementation, we add target link-layer address by default. 214 * We do not add one in MUST NOT cases. 215 */ 216 if (!IN6_IS_ADDR_MULTICAST(&daddr6)) 217 tlladdr = 0; 218 else 219 tlladdr = 1; 220 221 /* 222 * Target address (taddr6) must be either: 223 * (1) Valid unicast/anycast address for my receiving interface, 224 * (2) Unicast address for which I'm offering proxy service, or 225 * (3) "tentative" address on which DAD is being performed. 226 */ 227 /* (1) and (3) check. */ 228 if (ifp->if_carp) 229 ifa = (*carp_iamatch6_p)(ifp, &taddr6); 230 if (ifa == NULL) 231 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &taddr6); 232 233 /* (2) check. */ 234 if (ifa == NULL) { 235 struct route_in6 ro; 236 int need_proxy; 237 238 bzero(&ro, sizeof(ro)); 239 ro.ro_dst.sin6_len = sizeof(struct sockaddr_in6); 240 ro.ro_dst.sin6_family = AF_INET6; 241 ro.ro_dst.sin6_addr = taddr6; 242 243 /* Always use the default FIB. */ 244 #ifdef RADIX_MPATH 245 rtalloc_mpath_fib((struct route *)&ro, RTF_ANNOUNCE, 246 RT_DEFAULT_FIB); 247 #else 248 in6_rtalloc(&ro, RT_DEFAULT_FIB); 249 #endif 250 need_proxy = (ro.ro_rt && 251 (ro.ro_rt->rt_flags & RTF_ANNOUNCE) != 0 && 252 ro.ro_rt->rt_gateway->sa_family == AF_LINK); 253 if (ro.ro_rt != NULL) { 254 if (need_proxy) 255 proxydl = *SDL(ro.ro_rt->rt_gateway); 256 RTFREE(ro.ro_rt); 257 } 258 if (need_proxy) { 259 /* 260 * proxy NDP for single entry 261 */ 262 ifa = (struct ifaddr *)in6ifa_ifpforlinklocal(ifp, 263 IN6_IFF_NOTREADY|IN6_IFF_ANYCAST); 264 if (ifa) 265 proxy = 1; 266 } 267 } 268 if (ifa == NULL) { 269 /* 270 * We've got an NS packet, and we don't have that adddress 271 * assigned for us. We MUST silently ignore it. 272 * See RFC2461 7.2.3. 273 */ 274 goto freeit; 275 } 276 myaddr6 = *IFA_IN6(ifa); 277 anycast = ((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_ANYCAST; 278 tentative = ((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_TENTATIVE; 279 if (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_DUPLICATED) 280 goto freeit; 281 282 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) { 283 nd6log((LOG_INFO, "nd6_ns_input: lladdrlen mismatch for %s " 284 "(if %d, NS packet %d)\n", 285 ip6_sprintf(ip6bufs, &taddr6), 286 ifp->if_addrlen, lladdrlen - 2)); 287 goto bad; 288 } 289 290 if (IN6_ARE_ADDR_EQUAL(&myaddr6, &saddr6)) { 291 nd6log((LOG_INFO, "nd6_ns_input: duplicate IP6 address %s\n", 292 ip6_sprintf(ip6bufs, &saddr6))); 293 goto freeit; 294 } 295 296 /* 297 * We have neighbor solicitation packet, with target address equals to 298 * one of my tentative address. 299 * 300 * src addr how to process? 301 * --- --- 302 * multicast of course, invalid (rejected in ip6_input) 303 * unicast somebody is doing address resolution -> ignore 304 * unspec dup address detection 305 * 306 * The processing is defined in RFC 2462. 307 */ 308 if (tentative) { 309 /* 310 * If source address is unspecified address, it is for 311 * duplicate address detection. 312 * 313 * If not, the packet is for addess resolution; 314 * silently ignore it. 315 */ 316 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) 317 nd6_dad_ns_input(ifa); 318 319 goto freeit; 320 } 321 322 /* 323 * If the source address is unspecified address, entries must not 324 * be created or updated. 325 * It looks that sender is performing DAD. Output NA toward 326 * all-node multicast address, to tell the sender that I'm using 327 * the address. 328 * S bit ("solicited") must be zero. 329 */ 330 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) { 331 struct in6_addr in6_all; 332 333 in6_all = in6addr_linklocal_allnodes; 334 if (in6_setscope(&in6_all, ifp, NULL) != 0) 335 goto bad; 336 nd6_na_output_fib(ifp, &in6_all, &taddr6, 337 ((anycast || proxy || !tlladdr) ? 0 : ND_NA_FLAG_OVERRIDE) | 338 rflag, tlladdr, proxy ? (struct sockaddr *)&proxydl : NULL, 339 M_GETFIB(m)); 340 goto freeit; 341 } 342 343 nd6_cache_lladdr(ifp, &saddr6, lladdr, lladdrlen, 344 ND_NEIGHBOR_SOLICIT, 0); 345 346 nd6_na_output_fib(ifp, &saddr6, &taddr6, 347 ((anycast || proxy || !tlladdr) ? 0 : ND_NA_FLAG_OVERRIDE) | 348 rflag | ND_NA_FLAG_SOLICITED, tlladdr, 349 proxy ? (struct sockaddr *)&proxydl : NULL, M_GETFIB(m)); 350 freeit: 351 if (ifa != NULL) 352 ifa_free(ifa); 353 m_freem(m); 354 return; 355 356 bad: 357 nd6log((LOG_ERR, "nd6_ns_input: src=%s\n", 358 ip6_sprintf(ip6bufs, &saddr6))); 359 nd6log((LOG_ERR, "nd6_ns_input: dst=%s\n", 360 ip6_sprintf(ip6bufs, &daddr6))); 361 nd6log((LOG_ERR, "nd6_ns_input: tgt=%s\n", 362 ip6_sprintf(ip6bufs, &taddr6))); 363 ICMP6STAT_INC(icp6s_badns); 364 if (ifa != NULL) 365 ifa_free(ifa); 366 m_freem(m); 367 } 368 369 /* 370 * Output a Neighbor Solicitation Message. Caller specifies: 371 * - ICMP6 header source IP6 address 372 * - ND6 header target IP6 address 373 * - ND6 header source datalink address 374 * 375 * Based on RFC 2461 376 * Based on RFC 2462 (duplicate address detection) 377 * 378 * ln - for source address determination 379 * dad - duplicate address detection 380 */ 381 void 382 nd6_ns_output(struct ifnet *ifp, const struct in6_addr *daddr6, 383 const struct in6_addr *taddr6, struct llentry *ln, int dad) 384 { 385 struct mbuf *m; 386 struct m_tag *mtag; 387 struct ip6_hdr *ip6; 388 struct nd_neighbor_solicit *nd_ns; 389 struct ip6_moptions im6o; 390 int icmp6len; 391 int maxlen; 392 caddr_t mac; 393 struct route_in6 ro; 394 395 if (IN6_IS_ADDR_MULTICAST(taddr6)) 396 return; 397 398 /* estimate the size of message */ 399 maxlen = sizeof(*ip6) + sizeof(*nd_ns); 400 maxlen += (sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7; 401 KASSERT(max_linkhdr + maxlen <= MCLBYTES, ( 402 "%s: max_linkhdr + maxlen > MCLBYTES (%d + %d > %d)", 403 __func__, max_linkhdr, maxlen, MCLBYTES)); 404 405 MGETHDR(m, M_DONTWAIT, MT_DATA); 406 if (m && max_linkhdr + maxlen >= MHLEN) { 407 MCLGET(m, M_DONTWAIT); 408 if ((m->m_flags & M_EXT) == 0) { 409 m_free(m); 410 m = NULL; 411 } 412 } 413 if (m == NULL) 414 return; 415 m->m_pkthdr.rcvif = NULL; 416 417 bzero(&ro, sizeof(ro)); 418 419 if (daddr6 == NULL || IN6_IS_ADDR_MULTICAST(daddr6)) { 420 m->m_flags |= M_MCAST; 421 im6o.im6o_multicast_ifp = ifp; 422 im6o.im6o_multicast_hlim = 255; 423 im6o.im6o_multicast_loop = 0; 424 } 425 426 icmp6len = sizeof(*nd_ns); 427 m->m_pkthdr.len = m->m_len = sizeof(*ip6) + icmp6len; 428 m->m_data += max_linkhdr; /* or MH_ALIGN() equivalent? */ 429 430 /* fill neighbor solicitation packet */ 431 ip6 = mtod(m, struct ip6_hdr *); 432 ip6->ip6_flow = 0; 433 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 434 ip6->ip6_vfc |= IPV6_VERSION; 435 /* ip6->ip6_plen will be set later */ 436 ip6->ip6_nxt = IPPROTO_ICMPV6; 437 ip6->ip6_hlim = 255; 438 if (daddr6) 439 ip6->ip6_dst = *daddr6; 440 else { 441 ip6->ip6_dst.s6_addr16[0] = IPV6_ADDR_INT16_MLL; 442 ip6->ip6_dst.s6_addr16[1] = 0; 443 ip6->ip6_dst.s6_addr32[1] = 0; 444 ip6->ip6_dst.s6_addr32[2] = IPV6_ADDR_INT32_ONE; 445 ip6->ip6_dst.s6_addr32[3] = taddr6->s6_addr32[3]; 446 ip6->ip6_dst.s6_addr8[12] = 0xff; 447 if (in6_setscope(&ip6->ip6_dst, ifp, NULL) != 0) 448 goto bad; 449 } 450 if (!dad) { 451 struct ifaddr *ifa; 452 453 /* 454 * RFC2461 7.2.2: 455 * "If the source address of the packet prompting the 456 * solicitation is the same as one of the addresses assigned 457 * to the outgoing interface, that address SHOULD be placed 458 * in the IP Source Address of the outgoing solicitation. 459 * Otherwise, any one of the addresses assigned to the 460 * interface should be used." 461 * 462 * We use the source address for the prompting packet 463 * (saddr6), if: 464 * - saddr6 is given from the caller (by giving "ln"), and 465 * - saddr6 belongs to the outgoing interface. 466 * Otherwise, we perform the source address selection as usual. 467 */ 468 struct in6_addr *hsrc; 469 470 hsrc = NULL; 471 if (ln != NULL) { 472 LLE_RLOCK(ln); 473 if (ln->la_hold != NULL) { 474 struct ip6_hdr *hip6; /* hold ip6 */ 475 476 /* 477 * assuming every packet in la_hold has the same IP 478 * header 479 */ 480 hip6 = mtod(ln->la_hold, struct ip6_hdr *); 481 /* XXX pullup? */ 482 if (sizeof(*hip6) < ln->la_hold->m_len) { 483 ip6->ip6_src = hip6->ip6_src; 484 hsrc = &hip6->ip6_src; 485 } 486 } 487 LLE_RUNLOCK(ln); 488 } 489 if (hsrc && (ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, 490 hsrc)) != NULL) { 491 /* ip6_src set already. */ 492 ifa_free(ifa); 493 } else { 494 int error; 495 struct sockaddr_in6 dst_sa; 496 struct in6_addr src_in; 497 struct ifnet *oifp; 498 499 bzero(&dst_sa, sizeof(dst_sa)); 500 dst_sa.sin6_family = AF_INET6; 501 dst_sa.sin6_len = sizeof(dst_sa); 502 dst_sa.sin6_addr = ip6->ip6_dst; 503 504 oifp = ifp; 505 error = in6_selectsrc(&dst_sa, NULL, 506 NULL, &ro, NULL, &oifp, &src_in); 507 if (error) { 508 char ip6buf[INET6_ADDRSTRLEN]; 509 nd6log((LOG_DEBUG, 510 "nd6_ns_output: source can't be " 511 "determined: dst=%s, error=%d\n", 512 ip6_sprintf(ip6buf, &dst_sa.sin6_addr), 513 error)); 514 goto bad; 515 } 516 ip6->ip6_src = src_in; 517 } 518 } else { 519 /* 520 * Source address for DAD packet must always be IPv6 521 * unspecified address. (0::0) 522 * We actually don't have to 0-clear the address (we did it 523 * above), but we do so here explicitly to make the intention 524 * clearer. 525 */ 526 bzero(&ip6->ip6_src, sizeof(ip6->ip6_src)); 527 } 528 nd_ns = (struct nd_neighbor_solicit *)(ip6 + 1); 529 nd_ns->nd_ns_type = ND_NEIGHBOR_SOLICIT; 530 nd_ns->nd_ns_code = 0; 531 nd_ns->nd_ns_reserved = 0; 532 nd_ns->nd_ns_target = *taddr6; 533 in6_clearscope(&nd_ns->nd_ns_target); /* XXX */ 534 535 /* 536 * Add source link-layer address option. 537 * 538 * spec implementation 539 * --- --- 540 * DAD packet MUST NOT do not add the option 541 * there's no link layer address: 542 * impossible do not add the option 543 * there's link layer address: 544 * Multicast NS MUST add one add the option 545 * Unicast NS SHOULD add one add the option 546 */ 547 if (!dad && (mac = nd6_ifptomac(ifp))) { 548 int optlen = sizeof(struct nd_opt_hdr) + ifp->if_addrlen; 549 struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)(nd_ns + 1); 550 /* 8 byte alignments... */ 551 optlen = (optlen + 7) & ~7; 552 553 m->m_pkthdr.len += optlen; 554 m->m_len += optlen; 555 icmp6len += optlen; 556 bzero((caddr_t)nd_opt, optlen); 557 nd_opt->nd_opt_type = ND_OPT_SOURCE_LINKADDR; 558 nd_opt->nd_opt_len = optlen >> 3; 559 bcopy(mac, (caddr_t)(nd_opt + 1), ifp->if_addrlen); 560 } 561 562 ip6->ip6_plen = htons((u_short)icmp6len); 563 nd_ns->nd_ns_cksum = 0; 564 nd_ns->nd_ns_cksum = 565 in6_cksum(m, IPPROTO_ICMPV6, sizeof(*ip6), icmp6len); 566 567 if (send_sendso_input_hook != NULL) { 568 mtag = m_tag_get(PACKET_TAG_ND_OUTGOING, 569 sizeof(unsigned short), M_NOWAIT); 570 if (mtag == NULL) 571 goto bad; 572 *(unsigned short *)(mtag + 1) = nd_ns->nd_ns_type; 573 m_tag_prepend(m, mtag); 574 } 575 576 ip6_output(m, NULL, &ro, dad ? IPV6_UNSPECSRC : 0, &im6o, NULL, NULL); 577 icmp6_ifstat_inc(ifp, ifs6_out_msg); 578 icmp6_ifstat_inc(ifp, ifs6_out_neighborsolicit); 579 ICMP6STAT_INC(icp6s_outhist[ND_NEIGHBOR_SOLICIT]); 580 581 /* We don't cache this route. */ 582 RO_RTFREE(&ro); 583 584 return; 585 586 bad: 587 if (ro.ro_rt) { 588 RTFREE(ro.ro_rt); 589 } 590 m_freem(m); 591 return; 592 } 593 594 /* 595 * Neighbor advertisement input handling. 596 * 597 * Based on RFC 2461 598 * Based on RFC 2462 (duplicate address detection) 599 * 600 * the following items are not implemented yet: 601 * - proxy advertisement delay rule (RFC2461 7.2.8, last paragraph, SHOULD) 602 * - anycast advertisement delay rule (RFC2461 7.2.7, SHOULD) 603 */ 604 void 605 nd6_na_input(struct mbuf *m, int off, int icmp6len) 606 { 607 struct ifnet *ifp = m->m_pkthdr.rcvif; 608 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 609 struct nd_neighbor_advert *nd_na; 610 struct in6_addr daddr6 = ip6->ip6_dst; 611 struct in6_addr taddr6; 612 int flags; 613 int is_router; 614 int is_solicited; 615 int is_override; 616 char *lladdr = NULL; 617 int lladdrlen = 0; 618 int checklink = 0; 619 struct ifaddr *ifa; 620 struct llentry *ln = NULL; 621 union nd_opts ndopts; 622 struct mbuf *chain = NULL; 623 struct m_tag *mtag; 624 struct sockaddr_in6 sin6; 625 char ip6bufs[INET6_ADDRSTRLEN], ip6bufd[INET6_ADDRSTRLEN]; 626 627 if (ip6->ip6_hlim != 255) { 628 nd6log((LOG_ERR, 629 "nd6_na_input: invalid hlim (%d) from %s to %s on %s\n", 630 ip6->ip6_hlim, ip6_sprintf(ip6bufs, &ip6->ip6_src), 631 ip6_sprintf(ip6bufd, &ip6->ip6_dst), if_name(ifp))); 632 goto bad; 633 } 634 635 #ifndef PULLDOWN_TEST 636 IP6_EXTHDR_CHECK(m, off, icmp6len,); 637 nd_na = (struct nd_neighbor_advert *)((caddr_t)ip6 + off); 638 #else 639 IP6_EXTHDR_GET(nd_na, struct nd_neighbor_advert *, m, off, icmp6len); 640 if (nd_na == NULL) { 641 ICMP6STAT_INC(icp6s_tooshort); 642 return; 643 } 644 #endif 645 646 flags = nd_na->nd_na_flags_reserved; 647 is_router = ((flags & ND_NA_FLAG_ROUTER) != 0); 648 is_solicited = ((flags & ND_NA_FLAG_SOLICITED) != 0); 649 is_override = ((flags & ND_NA_FLAG_OVERRIDE) != 0); 650 651 taddr6 = nd_na->nd_na_target; 652 if (in6_setscope(&taddr6, ifp, NULL)) 653 goto bad; /* XXX: impossible */ 654 655 if (IN6_IS_ADDR_MULTICAST(&taddr6)) { 656 nd6log((LOG_ERR, 657 "nd6_na_input: invalid target address %s\n", 658 ip6_sprintf(ip6bufs, &taddr6))); 659 goto bad; 660 } 661 if (IN6_IS_ADDR_MULTICAST(&daddr6)) 662 if (is_solicited) { 663 nd6log((LOG_ERR, 664 "nd6_na_input: a solicited adv is multicasted\n")); 665 goto bad; 666 } 667 668 icmp6len -= sizeof(*nd_na); 669 nd6_option_init(nd_na + 1, icmp6len, &ndopts); 670 if (nd6_options(&ndopts) < 0) { 671 nd6log((LOG_INFO, 672 "nd6_na_input: invalid ND option, ignored\n")); 673 /* nd6_options have incremented stats */ 674 goto freeit; 675 } 676 677 if (ndopts.nd_opts_tgt_lladdr) { 678 lladdr = (char *)(ndopts.nd_opts_tgt_lladdr + 1); 679 lladdrlen = ndopts.nd_opts_tgt_lladdr->nd_opt_len << 3; 680 } 681 682 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &taddr6); 683 684 /* 685 * Target address matches one of my interface address. 686 * 687 * If my address is tentative, this means that there's somebody 688 * already using the same address as mine. This indicates DAD failure. 689 * This is defined in RFC 2462. 690 * 691 * Otherwise, process as defined in RFC 2461. 692 */ 693 if (ifa 694 && (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_TENTATIVE)) { 695 nd6_dad_na_input(ifa); 696 ifa_free(ifa); 697 goto freeit; 698 } 699 700 /* Just for safety, maybe unnecessary. */ 701 if (ifa) { 702 ifa_free(ifa); 703 log(LOG_ERR, 704 "nd6_na_input: duplicate IP6 address %s\n", 705 ip6_sprintf(ip6bufs, &taddr6)); 706 goto freeit; 707 } 708 709 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) { 710 nd6log((LOG_INFO, "nd6_na_input: lladdrlen mismatch for %s " 711 "(if %d, NA packet %d)\n", ip6_sprintf(ip6bufs, &taddr6), 712 ifp->if_addrlen, lladdrlen - 2)); 713 goto bad; 714 } 715 716 /* 717 * If no neighbor cache entry is found, NA SHOULD silently be 718 * discarded. 719 */ 720 IF_AFDATA_RLOCK(ifp); 721 ln = nd6_lookup(&taddr6, LLE_EXCLUSIVE, ifp); 722 IF_AFDATA_RUNLOCK(ifp); 723 if (ln == NULL) { 724 goto freeit; 725 } 726 727 if (ln->ln_state == ND6_LLINFO_INCOMPLETE) { 728 /* 729 * If the link-layer has address, and no lladdr option came, 730 * discard the packet. 731 */ 732 if (ifp->if_addrlen && lladdr == NULL) { 733 goto freeit; 734 } 735 736 /* 737 * Record link-layer address, and update the state. 738 */ 739 bcopy(lladdr, &ln->ll_addr, ifp->if_addrlen); 740 ln->la_flags |= LLE_VALID; 741 EVENTHANDLER_INVOKE(lle_event, ln, LLENTRY_RESOLVED); 742 if (is_solicited) { 743 ln->ln_state = ND6_LLINFO_REACHABLE; 744 ln->ln_byhint = 0; 745 if (!ND6_LLINFO_PERMANENT(ln)) { 746 nd6_llinfo_settimer_locked(ln, 747 (long)ND_IFINFO(ln->lle_tbl->llt_ifp)->reachable * hz); 748 } 749 } else { 750 ln->ln_state = ND6_LLINFO_STALE; 751 nd6_llinfo_settimer_locked(ln, (long)V_nd6_gctimer * hz); 752 } 753 if ((ln->ln_router = is_router) != 0) { 754 /* 755 * This means a router's state has changed from 756 * non-reachable to probably reachable, and might 757 * affect the status of associated prefixes.. 758 */ 759 checklink = 1; 760 } 761 } else { 762 int llchange; 763 764 /* 765 * Check if the link-layer address has changed or not. 766 */ 767 if (lladdr == NULL) 768 llchange = 0; 769 else { 770 if (ln->la_flags & LLE_VALID) { 771 if (bcmp(lladdr, &ln->ll_addr, ifp->if_addrlen)) 772 llchange = 1; 773 else 774 llchange = 0; 775 } else 776 llchange = 1; 777 } 778 779 /* 780 * This is VERY complex. Look at it with care. 781 * 782 * override solicit lladdr llchange action 783 * (L: record lladdr) 784 * 785 * 0 0 n -- (2c) 786 * 0 0 y n (2b) L 787 * 0 0 y y (1) REACHABLE->STALE 788 * 0 1 n -- (2c) *->REACHABLE 789 * 0 1 y n (2b) L *->REACHABLE 790 * 0 1 y y (1) REACHABLE->STALE 791 * 1 0 n -- (2a) 792 * 1 0 y n (2a) L 793 * 1 0 y y (2a) L *->STALE 794 * 1 1 n -- (2a) *->REACHABLE 795 * 1 1 y n (2a) L *->REACHABLE 796 * 1 1 y y (2a) L *->REACHABLE 797 */ 798 if (!is_override && (lladdr != NULL && llchange)) { /* (1) */ 799 /* 800 * If state is REACHABLE, make it STALE. 801 * no other updates should be done. 802 */ 803 if (ln->ln_state == ND6_LLINFO_REACHABLE) { 804 ln->ln_state = ND6_LLINFO_STALE; 805 nd6_llinfo_settimer_locked(ln, (long)V_nd6_gctimer * hz); 806 } 807 goto freeit; 808 } else if (is_override /* (2a) */ 809 || (!is_override && (lladdr != NULL && !llchange)) /* (2b) */ 810 || lladdr == NULL) { /* (2c) */ 811 /* 812 * Update link-local address, if any. 813 */ 814 if (lladdr != NULL) { 815 bcopy(lladdr, &ln->ll_addr, ifp->if_addrlen); 816 ln->la_flags |= LLE_VALID; 817 EVENTHANDLER_INVOKE(lle_event, ln, 818 LLENTRY_RESOLVED); 819 } 820 821 /* 822 * If solicited, make the state REACHABLE. 823 * If not solicited and the link-layer address was 824 * changed, make it STALE. 825 */ 826 if (is_solicited) { 827 ln->ln_state = ND6_LLINFO_REACHABLE; 828 ln->ln_byhint = 0; 829 if (!ND6_LLINFO_PERMANENT(ln)) { 830 nd6_llinfo_settimer_locked(ln, 831 (long)ND_IFINFO(ifp)->reachable * hz); 832 } 833 } else { 834 if (lladdr != NULL && llchange) { 835 ln->ln_state = ND6_LLINFO_STALE; 836 nd6_llinfo_settimer_locked(ln, 837 (long)V_nd6_gctimer * hz); 838 } 839 } 840 } 841 842 if (ln->ln_router && !is_router) { 843 /* 844 * The peer dropped the router flag. 845 * Remove the sender from the Default Router List and 846 * update the Destination Cache entries. 847 */ 848 struct nd_defrouter *dr; 849 struct in6_addr *in6; 850 851 in6 = &L3_ADDR_SIN6(ln)->sin6_addr; 852 853 /* 854 * Lock to protect the default router list. 855 * XXX: this might be unnecessary, since this function 856 * is only called under the network software interrupt 857 * context. However, we keep it just for safety. 858 */ 859 dr = defrouter_lookup(in6, ln->lle_tbl->llt_ifp); 860 if (dr) 861 defrtrlist_del(dr); 862 else if (ND_IFINFO(ln->lle_tbl->llt_ifp)->flags & 863 ND6_IFF_ACCEPT_RTADV) { 864 /* 865 * Even if the neighbor is not in the default 866 * router list, the neighbor may be used 867 * as a next hop for some destinations 868 * (e.g. redirect case). So we must 869 * call rt6_flush explicitly. 870 */ 871 rt6_flush(&ip6->ip6_src, ifp); 872 } 873 } 874 ln->ln_router = is_router; 875 } 876 /* XXX - QL 877 * Does this matter? 878 * rt->rt_flags &= ~RTF_REJECT; 879 */ 880 ln->la_asked = 0; 881 if (ln->la_hold) { 882 struct mbuf *m_hold, *m_hold_next; 883 884 /* 885 * reset the la_hold in advance, to explicitly 886 * prevent a la_hold lookup in nd6_output() 887 * (wouldn't happen, though...) 888 */ 889 for (m_hold = ln->la_hold, ln->la_hold = NULL; 890 m_hold; m_hold = m_hold_next) { 891 m_hold_next = m_hold->m_nextpkt; 892 m_hold->m_nextpkt = NULL; 893 /* 894 * we assume ifp is not a loopback here, so just set 895 * the 2nd argument as the 1st one. 896 */ 897 898 if (send_sendso_input_hook != NULL) { 899 mtag = m_tag_get(PACKET_TAG_ND_OUTGOING, 900 sizeof(unsigned short), M_NOWAIT); 901 if (mtag == NULL) 902 goto bad; 903 m_tag_prepend(m, mtag); 904 } 905 906 nd6_output_lle(ifp, ifp, m_hold, L3_ADDR_SIN6(ln), NULL, ln, &chain); 907 } 908 } 909 freeit: 910 if (ln != NULL) { 911 if (chain) 912 memcpy(&sin6, L3_ADDR_SIN6(ln), sizeof(sin6)); 913 LLE_WUNLOCK(ln); 914 915 if (chain) 916 nd6_output_flush(ifp, ifp, chain, &sin6, NULL); 917 } 918 if (checklink) 919 pfxlist_onlink_check(); 920 921 m_freem(m); 922 return; 923 924 bad: 925 if (ln != NULL) 926 LLE_WUNLOCK(ln); 927 928 ICMP6STAT_INC(icp6s_badna); 929 m_freem(m); 930 } 931 932 /* 933 * Neighbor advertisement output handling. 934 * 935 * Based on RFC 2461 936 * 937 * the following items are not implemented yet: 938 * - proxy advertisement delay rule (RFC2461 7.2.8, last paragraph, SHOULD) 939 * - anycast advertisement delay rule (RFC2461 7.2.7, SHOULD) 940 * 941 * tlladdr - 1 if include target link-layer address 942 * sdl0 - sockaddr_dl (= proxy NA) or NULL 943 */ 944 static void 945 nd6_na_output_fib(struct ifnet *ifp, const struct in6_addr *daddr6_0, 946 const struct in6_addr *taddr6, u_long flags, int tlladdr, 947 struct sockaddr *sdl0, u_int fibnum) 948 { 949 struct mbuf *m; 950 struct m_tag *mtag; 951 struct ifnet *oifp; 952 struct ip6_hdr *ip6; 953 struct nd_neighbor_advert *nd_na; 954 struct ip6_moptions im6o; 955 struct in6_addr src, daddr6; 956 struct sockaddr_in6 dst_sa; 957 int icmp6len, maxlen, error; 958 caddr_t mac = NULL; 959 struct route_in6 ro; 960 961 bzero(&ro, sizeof(ro)); 962 963 daddr6 = *daddr6_0; /* make a local copy for modification */ 964 965 /* estimate the size of message */ 966 maxlen = sizeof(*ip6) + sizeof(*nd_na); 967 maxlen += (sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7; 968 KASSERT(max_linkhdr + maxlen <= MCLBYTES, ( 969 "%s: max_linkhdr + maxlen > MCLBYTES (%d + %d > %d)", 970 __func__, max_linkhdr, maxlen, MCLBYTES)); 971 972 MGETHDR(m, M_DONTWAIT, MT_DATA); 973 if (m && max_linkhdr + maxlen >= MHLEN) { 974 MCLGET(m, M_DONTWAIT); 975 if ((m->m_flags & M_EXT) == 0) { 976 m_free(m); 977 m = NULL; 978 } 979 } 980 if (m == NULL) 981 return; 982 m->m_pkthdr.rcvif = NULL; 983 M_SETFIB(m, fibnum); 984 985 if (IN6_IS_ADDR_MULTICAST(&daddr6)) { 986 m->m_flags |= M_MCAST; 987 im6o.im6o_multicast_ifp = ifp; 988 im6o.im6o_multicast_hlim = 255; 989 im6o.im6o_multicast_loop = 0; 990 } 991 992 icmp6len = sizeof(*nd_na); 993 m->m_pkthdr.len = m->m_len = sizeof(struct ip6_hdr) + icmp6len; 994 m->m_data += max_linkhdr; /* or MH_ALIGN() equivalent? */ 995 996 /* fill neighbor advertisement packet */ 997 ip6 = mtod(m, struct ip6_hdr *); 998 ip6->ip6_flow = 0; 999 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 1000 ip6->ip6_vfc |= IPV6_VERSION; 1001 ip6->ip6_nxt = IPPROTO_ICMPV6; 1002 ip6->ip6_hlim = 255; 1003 if (IN6_IS_ADDR_UNSPECIFIED(&daddr6)) { 1004 /* reply to DAD */ 1005 daddr6.s6_addr16[0] = IPV6_ADDR_INT16_MLL; 1006 daddr6.s6_addr16[1] = 0; 1007 daddr6.s6_addr32[1] = 0; 1008 daddr6.s6_addr32[2] = 0; 1009 daddr6.s6_addr32[3] = IPV6_ADDR_INT32_ONE; 1010 if (in6_setscope(&daddr6, ifp, NULL)) 1011 goto bad; 1012 1013 flags &= ~ND_NA_FLAG_SOLICITED; 1014 } 1015 ip6->ip6_dst = daddr6; 1016 bzero(&dst_sa, sizeof(struct sockaddr_in6)); 1017 dst_sa.sin6_family = AF_INET6; 1018 dst_sa.sin6_len = sizeof(struct sockaddr_in6); 1019 dst_sa.sin6_addr = daddr6; 1020 1021 /* 1022 * Select a source whose scope is the same as that of the dest. 1023 */ 1024 bcopy(&dst_sa, &ro.ro_dst, sizeof(dst_sa)); 1025 oifp = ifp; 1026 error = in6_selectsrc(&dst_sa, NULL, NULL, &ro, NULL, &oifp, &src); 1027 if (error) { 1028 char ip6buf[INET6_ADDRSTRLEN]; 1029 nd6log((LOG_DEBUG, "nd6_na_output: source can't be " 1030 "determined: dst=%s, error=%d\n", 1031 ip6_sprintf(ip6buf, &dst_sa.sin6_addr), error)); 1032 goto bad; 1033 } 1034 ip6->ip6_src = src; 1035 nd_na = (struct nd_neighbor_advert *)(ip6 + 1); 1036 nd_na->nd_na_type = ND_NEIGHBOR_ADVERT; 1037 nd_na->nd_na_code = 0; 1038 nd_na->nd_na_target = *taddr6; 1039 in6_clearscope(&nd_na->nd_na_target); /* XXX */ 1040 1041 /* 1042 * "tlladdr" indicates NS's condition for adding tlladdr or not. 1043 * see nd6_ns_input() for details. 1044 * Basically, if NS packet is sent to unicast/anycast addr, 1045 * target lladdr option SHOULD NOT be included. 1046 */ 1047 if (tlladdr) { 1048 /* 1049 * sdl0 != NULL indicates proxy NA. If we do proxy, use 1050 * lladdr in sdl0. If we are not proxying (sending NA for 1051 * my address) use lladdr configured for the interface. 1052 */ 1053 if (sdl0 == NULL) { 1054 if (ifp->if_carp) 1055 mac = (*carp_macmatch6_p)(ifp, m, taddr6); 1056 if (mac == NULL) 1057 mac = nd6_ifptomac(ifp); 1058 } else if (sdl0->sa_family == AF_LINK) { 1059 struct sockaddr_dl *sdl; 1060 sdl = (struct sockaddr_dl *)sdl0; 1061 if (sdl->sdl_alen == ifp->if_addrlen) 1062 mac = LLADDR(sdl); 1063 } 1064 } 1065 if (tlladdr && mac) { 1066 int optlen = sizeof(struct nd_opt_hdr) + ifp->if_addrlen; 1067 struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)(nd_na + 1); 1068 1069 /* roundup to 8 bytes alignment! */ 1070 optlen = (optlen + 7) & ~7; 1071 1072 m->m_pkthdr.len += optlen; 1073 m->m_len += optlen; 1074 icmp6len += optlen; 1075 bzero((caddr_t)nd_opt, optlen); 1076 nd_opt->nd_opt_type = ND_OPT_TARGET_LINKADDR; 1077 nd_opt->nd_opt_len = optlen >> 3; 1078 bcopy(mac, (caddr_t)(nd_opt + 1), ifp->if_addrlen); 1079 } else 1080 flags &= ~ND_NA_FLAG_OVERRIDE; 1081 1082 ip6->ip6_plen = htons((u_short)icmp6len); 1083 nd_na->nd_na_flags_reserved = flags; 1084 nd_na->nd_na_cksum = 0; 1085 nd_na->nd_na_cksum = 1086 in6_cksum(m, IPPROTO_ICMPV6, sizeof(struct ip6_hdr), icmp6len); 1087 1088 if (send_sendso_input_hook != NULL) { 1089 mtag = m_tag_get(PACKET_TAG_ND_OUTGOING, 1090 sizeof(unsigned short), M_NOWAIT); 1091 if (mtag == NULL) 1092 goto bad; 1093 *(unsigned short *)(mtag + 1) = nd_na->nd_na_type; 1094 m_tag_prepend(m, mtag); 1095 } 1096 1097 ip6_output(m, NULL, &ro, 0, &im6o, NULL, NULL); 1098 icmp6_ifstat_inc(ifp, ifs6_out_msg); 1099 icmp6_ifstat_inc(ifp, ifs6_out_neighboradvert); 1100 ICMP6STAT_INC(icp6s_outhist[ND_NEIGHBOR_ADVERT]); 1101 1102 /* We don't cache this route. */ 1103 RO_RTFREE(&ro); 1104 1105 return; 1106 1107 bad: 1108 if (ro.ro_rt) { 1109 RTFREE(ro.ro_rt); 1110 } 1111 m_freem(m); 1112 return; 1113 } 1114 1115 #ifndef BURN_BRIDGES 1116 void 1117 nd6_na_output(struct ifnet *ifp, const struct in6_addr *daddr6_0, 1118 const struct in6_addr *taddr6, u_long flags, int tlladdr, 1119 struct sockaddr *sdl0) 1120 { 1121 1122 nd6_na_output_fib(ifp, daddr6_0, taddr6, flags, tlladdr, sdl0, 1123 RT_DEFAULT_FIB); 1124 } 1125 #endif 1126 1127 caddr_t 1128 nd6_ifptomac(struct ifnet *ifp) 1129 { 1130 switch (ifp->if_type) { 1131 case IFT_ARCNET: 1132 case IFT_ETHER: 1133 case IFT_FDDI: 1134 case IFT_IEEE1394: 1135 #ifdef IFT_L2VLAN 1136 case IFT_L2VLAN: 1137 #endif 1138 #ifdef IFT_IEEE80211 1139 case IFT_IEEE80211: 1140 #endif 1141 #ifdef IFT_CARP 1142 case IFT_CARP: 1143 #endif 1144 case IFT_INFINIBAND: 1145 case IFT_BRIDGE: 1146 case IFT_ISO88025: 1147 return IF_LLADDR(ifp); 1148 default: 1149 return NULL; 1150 } 1151 } 1152 1153 struct dadq { 1154 TAILQ_ENTRY(dadq) dad_list; 1155 struct ifaddr *dad_ifa; 1156 int dad_count; /* max NS to send */ 1157 int dad_ns_tcount; /* # of trials to send NS */ 1158 int dad_ns_ocount; /* NS sent so far */ 1159 int dad_ns_icount; 1160 int dad_na_icount; 1161 struct callout dad_timer_ch; 1162 struct vnet *dad_vnet; 1163 }; 1164 1165 static VNET_DEFINE(TAILQ_HEAD(, dadq), dadq); 1166 VNET_DEFINE(int, dad_init) = 0; 1167 #define V_dadq VNET(dadq) 1168 #define V_dad_init VNET(dad_init) 1169 1170 static struct dadq * 1171 nd6_dad_find(struct ifaddr *ifa) 1172 { 1173 struct dadq *dp; 1174 1175 TAILQ_FOREACH(dp, &V_dadq, dad_list) 1176 if (dp->dad_ifa == ifa) 1177 return (dp); 1178 1179 return (NULL); 1180 } 1181 1182 static void 1183 nd6_dad_starttimer(struct dadq *dp, int ticks) 1184 { 1185 1186 callout_reset(&dp->dad_timer_ch, ticks, 1187 (void (*)(void *))nd6_dad_timer, (void *)dp); 1188 } 1189 1190 static void 1191 nd6_dad_stoptimer(struct dadq *dp) 1192 { 1193 1194 callout_stop(&dp->dad_timer_ch); 1195 } 1196 1197 /* 1198 * Start Duplicate Address Detection (DAD) for specified interface address. 1199 */ 1200 void 1201 nd6_dad_start(struct ifaddr *ifa, int delay) 1202 { 1203 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1204 struct dadq *dp; 1205 char ip6buf[INET6_ADDRSTRLEN]; 1206 1207 if (!V_dad_init) { 1208 TAILQ_INIT(&V_dadq); 1209 V_dad_init++; 1210 } 1211 1212 /* 1213 * If we don't need DAD, don't do it. 1214 * There are several cases: 1215 * - DAD is disabled (ip6_dad_count == 0) 1216 * - the interface address is anycast 1217 */ 1218 if (!(ia->ia6_flags & IN6_IFF_TENTATIVE)) { 1219 log(LOG_DEBUG, 1220 "nd6_dad_start: called with non-tentative address " 1221 "%s(%s)\n", 1222 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr), 1223 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1224 return; 1225 } 1226 if (ia->ia6_flags & IN6_IFF_ANYCAST) { 1227 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1228 return; 1229 } 1230 if (!V_ip6_dad_count) { 1231 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1232 return; 1233 } 1234 if (ifa->ifa_ifp == NULL) 1235 panic("nd6_dad_start: ifa->ifa_ifp == NULL"); 1236 if (!(ifa->ifa_ifp->if_flags & IFF_UP)) { 1237 return; 1238 } 1239 if (ND_IFINFO(ifa->ifa_ifp)->flags & ND6_IFF_IFDISABLED) 1240 return; 1241 if (nd6_dad_find(ifa) != NULL) { 1242 /* DAD already in progress */ 1243 return; 1244 } 1245 1246 dp = malloc(sizeof(*dp), M_IP6NDP, M_NOWAIT); 1247 if (dp == NULL) { 1248 log(LOG_ERR, "nd6_dad_start: memory allocation failed for " 1249 "%s(%s)\n", 1250 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr), 1251 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1252 return; 1253 } 1254 bzero(dp, sizeof(*dp)); 1255 callout_init(&dp->dad_timer_ch, 0); 1256 #ifdef VIMAGE 1257 dp->dad_vnet = curvnet; 1258 #endif 1259 TAILQ_INSERT_TAIL(&V_dadq, (struct dadq *)dp, dad_list); 1260 1261 nd6log((LOG_DEBUG, "%s: starting DAD for %s\n", if_name(ifa->ifa_ifp), 1262 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr))); 1263 1264 /* 1265 * Send NS packet for DAD, ip6_dad_count times. 1266 * Note that we must delay the first transmission, if this is the 1267 * first packet to be sent from the interface after interface 1268 * (re)initialization. 1269 */ 1270 dp->dad_ifa = ifa; 1271 ifa_ref(ifa); /* just for safety */ 1272 dp->dad_count = V_ip6_dad_count; 1273 dp->dad_ns_icount = dp->dad_na_icount = 0; 1274 dp->dad_ns_ocount = dp->dad_ns_tcount = 0; 1275 if (delay == 0) { 1276 nd6_dad_ns_output(dp, ifa); 1277 nd6_dad_starttimer(dp, 1278 (long)ND_IFINFO(ifa->ifa_ifp)->retrans * hz / 1000); 1279 } else { 1280 nd6_dad_starttimer(dp, delay); 1281 } 1282 } 1283 1284 /* 1285 * terminate DAD unconditionally. used for address removals. 1286 */ 1287 void 1288 nd6_dad_stop(struct ifaddr *ifa) 1289 { 1290 struct dadq *dp; 1291 1292 if (!V_dad_init) 1293 return; 1294 dp = nd6_dad_find(ifa); 1295 if (!dp) { 1296 /* DAD wasn't started yet */ 1297 return; 1298 } 1299 1300 nd6_dad_stoptimer(dp); 1301 1302 TAILQ_REMOVE(&V_dadq, (struct dadq *)dp, dad_list); 1303 free(dp, M_IP6NDP); 1304 dp = NULL; 1305 ifa_free(ifa); 1306 } 1307 1308 static void 1309 nd6_dad_timer(struct dadq *dp) 1310 { 1311 CURVNET_SET(dp->dad_vnet); 1312 int s; 1313 struct ifaddr *ifa = dp->dad_ifa; 1314 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1315 char ip6buf[INET6_ADDRSTRLEN]; 1316 1317 s = splnet(); /* XXX */ 1318 1319 /* Sanity check */ 1320 if (ia == NULL) { 1321 log(LOG_ERR, "nd6_dad_timer: called with null parameter\n"); 1322 goto done; 1323 } 1324 if (ia->ia6_flags & IN6_IFF_DUPLICATED) { 1325 log(LOG_ERR, "nd6_dad_timer: called with duplicated address " 1326 "%s(%s)\n", 1327 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr), 1328 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1329 goto done; 1330 } 1331 if ((ia->ia6_flags & IN6_IFF_TENTATIVE) == 0) { 1332 log(LOG_ERR, "nd6_dad_timer: called with non-tentative address " 1333 "%s(%s)\n", 1334 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr), 1335 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1336 goto done; 1337 } 1338 1339 /* timeouted with IFF_{RUNNING,UP} check */ 1340 if (dp->dad_ns_tcount > V_dad_maxtry) { 1341 nd6log((LOG_INFO, "%s: could not run DAD, driver problem?\n", 1342 if_name(ifa->ifa_ifp))); 1343 1344 TAILQ_REMOVE(&V_dadq, (struct dadq *)dp, dad_list); 1345 free(dp, M_IP6NDP); 1346 dp = NULL; 1347 ifa_free(ifa); 1348 goto done; 1349 } 1350 1351 /* Need more checks? */ 1352 if (dp->dad_ns_ocount < dp->dad_count) { 1353 /* 1354 * We have more NS to go. Send NS packet for DAD. 1355 */ 1356 nd6_dad_ns_output(dp, ifa); 1357 nd6_dad_starttimer(dp, 1358 (long)ND_IFINFO(ifa->ifa_ifp)->retrans * hz / 1000); 1359 } else { 1360 /* 1361 * We have transmitted sufficient number of DAD packets. 1362 * See what we've got. 1363 */ 1364 int duplicate; 1365 1366 duplicate = 0; 1367 1368 if (dp->dad_na_icount) { 1369 /* 1370 * the check is in nd6_dad_na_input(), 1371 * but just in case 1372 */ 1373 duplicate++; 1374 } 1375 1376 if (dp->dad_ns_icount) { 1377 /* We've seen NS, means DAD has failed. */ 1378 duplicate++; 1379 } 1380 1381 if (duplicate) { 1382 /* (*dp) will be freed in nd6_dad_duplicated() */ 1383 dp = NULL; 1384 nd6_dad_duplicated(ifa); 1385 } else { 1386 /* 1387 * We are done with DAD. No NA came, no NS came. 1388 * No duplicate address found. 1389 */ 1390 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1391 1392 nd6log((LOG_DEBUG, 1393 "%s: DAD complete for %s - no duplicates found\n", 1394 if_name(ifa->ifa_ifp), 1395 ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr))); 1396 1397 TAILQ_REMOVE(&V_dadq, (struct dadq *)dp, dad_list); 1398 free(dp, M_IP6NDP); 1399 dp = NULL; 1400 ifa_free(ifa); 1401 } 1402 } 1403 1404 done: 1405 splx(s); 1406 CURVNET_RESTORE(); 1407 } 1408 1409 void 1410 nd6_dad_duplicated(struct ifaddr *ifa) 1411 { 1412 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1413 struct ifnet *ifp; 1414 struct dadq *dp; 1415 char ip6buf[INET6_ADDRSTRLEN]; 1416 1417 dp = nd6_dad_find(ifa); 1418 if (dp == NULL) { 1419 log(LOG_ERR, "nd6_dad_duplicated: DAD structure not found\n"); 1420 return; 1421 } 1422 1423 log(LOG_ERR, "%s: DAD detected duplicate IPv6 address %s: " 1424 "NS in/out=%d/%d, NA in=%d\n", 1425 if_name(ifa->ifa_ifp), ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr), 1426 dp->dad_ns_icount, dp->dad_ns_ocount, dp->dad_na_icount); 1427 1428 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1429 ia->ia6_flags |= IN6_IFF_DUPLICATED; 1430 1431 /* We are done with DAD, with duplicate address found. (failure) */ 1432 nd6_dad_stoptimer(dp); 1433 1434 ifp = ifa->ifa_ifp; 1435 log(LOG_ERR, "%s: DAD complete for %s - duplicate found\n", 1436 if_name(ifp), ip6_sprintf(ip6buf, &ia->ia_addr.sin6_addr)); 1437 log(LOG_ERR, "%s: manual intervention required\n", 1438 if_name(ifp)); 1439 1440 /* 1441 * If the address is a link-local address formed from an interface 1442 * identifier based on the hardware address which is supposed to be 1443 * uniquely assigned (e.g., EUI-64 for an Ethernet interface), IP 1444 * operation on the interface SHOULD be disabled. 1445 * [RFC 4862, Section 5.4.5] 1446 */ 1447 if (IN6_IS_ADDR_LINKLOCAL(&ia->ia_addr.sin6_addr)) { 1448 struct in6_addr in6; 1449 1450 /* 1451 * To avoid over-reaction, we only apply this logic when we are 1452 * very sure that hardware addresses are supposed to be unique. 1453 */ 1454 switch (ifp->if_type) { 1455 case IFT_ETHER: 1456 case IFT_FDDI: 1457 case IFT_ATM: 1458 case IFT_IEEE1394: 1459 #ifdef IFT_IEEE80211 1460 case IFT_IEEE80211: 1461 #endif 1462 case IFT_INFINIBAND: 1463 in6 = ia->ia_addr.sin6_addr; 1464 if (in6_get_hw_ifid(ifp, &in6) == 0 && 1465 IN6_ARE_ADDR_EQUAL(&ia->ia_addr.sin6_addr, &in6)) { 1466 ND_IFINFO(ifp)->flags |= ND6_IFF_IFDISABLED; 1467 log(LOG_ERR, "%s: possible hardware address " 1468 "duplication detected, disable IPv6\n", 1469 if_name(ifp)); 1470 } 1471 break; 1472 } 1473 } 1474 1475 TAILQ_REMOVE(&V_dadq, (struct dadq *)dp, dad_list); 1476 free(dp, M_IP6NDP); 1477 dp = NULL; 1478 ifa_free(ifa); 1479 } 1480 1481 static void 1482 nd6_dad_ns_output(struct dadq *dp, struct ifaddr *ifa) 1483 { 1484 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1485 struct ifnet *ifp = ifa->ifa_ifp; 1486 1487 dp->dad_ns_tcount++; 1488 if ((ifp->if_flags & IFF_UP) == 0) { 1489 return; 1490 } 1491 if ((ifp->if_drv_flags & IFF_DRV_RUNNING) == 0) { 1492 return; 1493 } 1494 1495 dp->dad_ns_ocount++; 1496 nd6_ns_output(ifp, NULL, &ia->ia_addr.sin6_addr, NULL, 1); 1497 } 1498 1499 static void 1500 nd6_dad_ns_input(struct ifaddr *ifa) 1501 { 1502 struct in6_ifaddr *ia; 1503 struct ifnet *ifp; 1504 const struct in6_addr *taddr6; 1505 struct dadq *dp; 1506 int duplicate; 1507 1508 if (ifa == NULL) 1509 panic("ifa == NULL in nd6_dad_ns_input"); 1510 1511 ia = (struct in6_ifaddr *)ifa; 1512 ifp = ifa->ifa_ifp; 1513 taddr6 = &ia->ia_addr.sin6_addr; 1514 duplicate = 0; 1515 dp = nd6_dad_find(ifa); 1516 1517 /* Quickhack - completely ignore DAD NS packets */ 1518 if (V_dad_ignore_ns) { 1519 char ip6buf[INET6_ADDRSTRLEN]; 1520 nd6log((LOG_INFO, 1521 "nd6_dad_ns_input: ignoring DAD NS packet for " 1522 "address %s(%s)\n", ip6_sprintf(ip6buf, taddr6), 1523 if_name(ifa->ifa_ifp))); 1524 return; 1525 } 1526 1527 /* 1528 * if I'm yet to start DAD, someone else started using this address 1529 * first. I have a duplicate and you win. 1530 */ 1531 if (dp == NULL || dp->dad_ns_ocount == 0) 1532 duplicate++; 1533 1534 /* XXX more checks for loopback situation - see nd6_dad_timer too */ 1535 1536 if (duplicate) { 1537 dp = NULL; /* will be freed in nd6_dad_duplicated() */ 1538 nd6_dad_duplicated(ifa); 1539 } else { 1540 /* 1541 * not sure if I got a duplicate. 1542 * increment ns count and see what happens. 1543 */ 1544 if (dp) 1545 dp->dad_ns_icount++; 1546 } 1547 } 1548 1549 static void 1550 nd6_dad_na_input(struct ifaddr *ifa) 1551 { 1552 struct dadq *dp; 1553 1554 if (ifa == NULL) 1555 panic("ifa == NULL in nd6_dad_na_input"); 1556 1557 dp = nd6_dad_find(ifa); 1558 if (dp) 1559 dp->dad_na_icount++; 1560 1561 /* remove the address. */ 1562 nd6_dad_duplicated(ifa); 1563 }
Cache object: 6aa53f261a973643759a81c383c15c0a
[ source navigation ] [ diff markup ] [ identifier search ] [ freetext search ] [ file search ] [ list types ] [ track identifier ]