1 /* $FreeBSD: src/sys/netinet6/nd6_nbr.c,v 1.4.2.6 2003/01/23 21:06:47 sam Exp $ */ 2 /* $KAME: nd6_nbr.c,v 1.86 2002/01/21 02:33:04 jinmei Exp $ */ 3 4 /* 5 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project. 6 * All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. Neither the name of the project nor the names of its contributors 17 * may be used to endorse or promote products derived from this software 18 * without specific prior written permission. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND 21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE 24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30 * SUCH DAMAGE. 31 */ 32 33 #include "opt_inet.h" 34 #include "opt_inet6.h" 35 #include "opt_ipsec.h" 36 #include "opt_carp.h" 37 38 #include <sys/param.h> 39 #include <sys/systm.h> 40 #include <sys/malloc.h> 41 #include <sys/mbuf.h> 42 #include <sys/socket.h> 43 #include <sys/sockio.h> 44 #include <sys/time.h> 45 #include <sys/kernel.h> 46 #include <sys/errno.h> 47 #include <sys/syslog.h> 48 #include <sys/queue.h> 49 #include <sys/callout.h> 50 #include <sys/mutex.h> 51 52 #include <sys/thread2.h> 53 #include <sys/mutex2.h> 54 55 #include <net/if.h> 56 #include <net/if_types.h> 57 #include <net/if_dl.h> 58 #include <net/route.h> 59 #include <net/netisr2.h> 60 #include <net/netmsg2.h> 61 62 #include <netinet/in.h> 63 #include <netinet/in_var.h> 64 #include <netinet6/in6_var.h> 65 #include <netinet/ip6.h> 66 #include <netinet6/ip6_var.h> 67 #include <netinet6/nd6.h> 68 #include <netinet/icmp6.h> 69 70 #ifdef IPSEC 71 #include <netinet6/ipsec.h> 72 #ifdef INET6 73 #include <netinet6/ipsec6.h> 74 #endif 75 #endif 76 77 #include <net/net_osdep.h> 78 79 #ifdef CARP 80 #include <netinet/ip_carp.h> 81 #endif 82 83 84 #define SDL(s) ((struct sockaddr_dl *)s) 85 86 struct dadq; 87 static struct dadq *nd6_dad_find(struct ifaddr *); 88 static void nd6_dad_starttimer(struct dadq *, int); 89 static void nd6_dad_stoptimer(struct dadq *); 90 static void nd6_dad_timer(void *); 91 static void nd6_dad_timer_handler(netmsg_t); 92 static void nd6_dad_ns_output(struct dadq *); 93 static void nd6_dad_ns_input(struct ifaddr *); 94 static void nd6_dad_na_input(struct ifaddr *); 95 static struct dadq *nd6_dad_create(struct ifaddr *); 96 static void nd6_dad_destroy(struct dadq *); 97 static void nd6_dad_duplicated(struct ifaddr *); 98 99 static int dad_ignore_ns = 0; /* ignore NS in DAD - specwise incorrect*/ 100 static int dad_maxtry = 15; /* max # of *tries* to transmit DAD packet */ 101 102 /* 103 * Input an Neighbor Solicitation Message. 104 * 105 * Based on RFC 2461 106 * Based on RFC 2462 (duplicated address detection) 107 */ 108 void 109 nd6_ns_input(struct mbuf *m, int off, int icmp6len) 110 { 111 struct ifnet *ifp = m->m_pkthdr.rcvif; 112 struct ifnet *cmpifp; 113 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 114 struct nd_neighbor_solicit *nd_ns; 115 struct in6_addr saddr6 = ip6->ip6_src; 116 struct in6_addr daddr6 = ip6->ip6_dst; 117 struct in6_addr taddr6; 118 struct in6_addr myaddr6; 119 char *lladdr = NULL; 120 struct ifaddr *ifa = NULL; 121 int lladdrlen = 0; 122 int anycast = 0, proxy = 0, tentative = 0; 123 int tlladdr; 124 union nd_opts ndopts; 125 struct sockaddr_dl *proxydl = NULL; 126 127 /* 128 * Collapse interfaces to the bridge for comparison and 129 * mac (llinfo) purposes. 130 */ 131 cmpifp = ifp; 132 if (ifp->if_bridge) 133 cmpifp = ifp->if_bridge; 134 135 #ifndef PULLDOWN_TEST 136 IP6_EXTHDR_CHECK(m, off, icmp6len,); 137 nd_ns = (struct nd_neighbor_solicit *)((caddr_t)ip6 + off); 138 #else 139 IP6_EXTHDR_GET(nd_ns, struct nd_neighbor_solicit *, m, off, icmp6len); 140 if (nd_ns == NULL) { 141 icmp6stat.icp6s_tooshort++; 142 return; 143 } 144 #endif 145 ip6 = mtod(m, struct ip6_hdr *); /* adjust pointer for safety */ 146 taddr6 = nd_ns->nd_ns_target; 147 148 if (ip6->ip6_hlim != 255) { 149 nd6log((LOG_ERR, 150 "nd6_ns_input: invalid hlim (%d) from %s to %s on %s\n", 151 ip6->ip6_hlim, ip6_sprintf(&ip6->ip6_src), 152 ip6_sprintf(&ip6->ip6_dst), if_name(ifp))); 153 goto bad; 154 } 155 156 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) { 157 /* dst has to be solicited node multicast address. */ 158 if (daddr6.s6_addr16[0] == IPV6_ADDR_INT16_MLL 159 /* don't check ifindex portion */ 160 && daddr6.s6_addr32[1] == 0 161 && daddr6.s6_addr32[2] == IPV6_ADDR_INT32_ONE 162 && daddr6.s6_addr8[12] == 0xff) { 163 ; /* good */ 164 } else { 165 nd6log((LOG_INFO, "nd6_ns_input: bad DAD packet " 166 "(wrong ip6 dst)\n")); 167 goto bad; 168 } 169 } else if (!nd6_onlink_ns_rfc4861) { 170 /* 171 * Make sure the source address is from a neighbor's address. 172 * 173 * XXX probably only need to check cmpifp. 174 */ 175 if (in6ifa_ifplocaladdr(cmpifp, &saddr6) == NULL && 176 in6ifa_ifplocaladdr(ifp, &saddr6) == NULL) { 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 if (IN6_IS_SCOPE_LINKLOCAL(&taddr6)) 189 taddr6.s6_addr16[1] = htons(ifp->if_index); 190 191 icmp6len -= sizeof(*nd_ns); 192 nd6_option_init(nd_ns + 1, icmp6len, &ndopts); 193 if (nd6_options(&ndopts) < 0) { 194 nd6log((LOG_INFO, 195 "nd6_ns_input: invalid ND option, ignored\n")); 196 /* nd6_options have incremented stats */ 197 goto freeit; 198 } 199 200 if (ndopts.nd_opts_src_lladdr) { 201 lladdr = (char *)(ndopts.nd_opts_src_lladdr + 1); 202 lladdrlen = ndopts.nd_opts_src_lladdr->nd_opt_len << 3; 203 } 204 205 if (IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_src) && lladdr) { 206 nd6log((LOG_INFO, "nd6_ns_input: bad DAD packet " 207 "(link-layer address option)\n")); 208 goto bad; 209 } 210 211 /* 212 * Attaching target link-layer address to the NA? 213 * (RFC 2461 7.2.4) 214 * 215 * NS IP dst is unicast/anycast MUST NOT add 216 * NS IP dst is solicited-node multicast MUST add 217 * 218 * In implementation, we add target link-layer address by default. 219 * We do not add one in MUST NOT cases. 220 */ 221 #if 0 /* too much! */ 222 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &daddr6); 223 if (ifa && (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_ANYCAST)) 224 tlladdr = 0; 225 else 226 #endif 227 if (!IN6_IS_ADDR_MULTICAST(&daddr6)) 228 tlladdr = 0; 229 else 230 tlladdr = 1; 231 232 /* 233 * Target address (taddr6) must be either: 234 * (1) Valid unicast/anycast address for my receiving interface. 235 * (2) Unicast or anycast address for which I'm offering proxy 236 * service. 237 * (3) "tentative" address on which DAD is being performed. 238 */ 239 /* (1) and (3) check. */ 240 #ifdef CARP 241 if (ifp->if_carp) 242 ifa = carp_iamatch6(ifp->if_carp, &taddr6); 243 if (!ifa) 244 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &taddr6); 245 #else 246 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &taddr6); 247 #endif 248 249 /* 250 * (2) Check proxying. Requires ip6_forwarding to be turned on. 251 * 252 * If the packet is anycast the target route must be on a 253 * different interface because the anycast will get anything 254 * on the current interface. 255 * 256 * If the packet is unicast the target route may be on the 257 * same interface. If the gateway is a (typically manually 258 * configured) link address we can directly offer it. 259 * XXX for now we don't do this but instead offer ours and 260 * presumably relay. 261 * 262 * WARNING! Since this is a subnet proxy the interface proxying 263 * the ND6 must be in promiscuous mode or it will not see the 264 * solicited multicast requests for various hosts being proxied. 265 * 266 * WARNING! Since this is a subnet proxy we have to treat bridge 267 * interfaces as being the bridge itself so we do not proxy-nd6 268 * between bridge interfaces (which are effectively switched). 269 * 270 * (In the specific-host-proxy case via RTF_ANNOUNCE, which is 271 * a bitch to configure, a specific multicast route is already 272 * added for that host <-- NOT RECOMMENDED). 273 */ 274 if (!ifa && ip6_forwarding) { 275 struct rtentry *rt; 276 struct sockaddr_in6 tsin6; 277 struct ifnet *rtifp; 278 279 bzero(&tsin6, sizeof tsin6); 280 tsin6.sin6_len = sizeof(struct sockaddr_in6); 281 tsin6.sin6_family = AF_INET6; 282 tsin6.sin6_addr = taddr6; 283 284 rt = rtpurelookup((struct sockaddr *)&tsin6); 285 rtifp = rt ? rt->rt_ifp : NULL; 286 if (rtifp && rtifp->if_bridge) 287 rtifp = rtifp->if_bridge; 288 289 if (rt != NULL && 290 (cmpifp != rtifp || 291 (cmpifp == rtifp && (m->m_flags & M_MCAST) == 0)) 292 ) { 293 ifa = (struct ifaddr *)in6ifa_ifpforlinklocal(cmpifp, 294 IN6_IFF_NOTREADY|IN6_IFF_ANYCAST); 295 nd6log((LOG_INFO, 296 "nd6_ns_input: nd6 proxy %s(%s)<-%s ifa %p\n", 297 if_name(cmpifp), if_name(ifp), 298 if_name(rtifp), ifa)); 299 if (ifa) { 300 proxy = 1; 301 /* 302 * Manual link address on same interface 303 * w/announce flag will proxy-arp using 304 * target mac, else our mac is used. 305 */ 306 if (cmpifp == rtifp && 307 (rt->rt_flags & RTF_ANNOUNCE) && 308 rt->rt_gateway->sa_family == AF_LINK) { 309 proxydl = SDL(rt->rt_gateway); 310 } 311 } 312 } 313 if (rt != NULL) 314 --rt->rt_refcnt; 315 } 316 if (ifa == NULL) { 317 /* 318 * We've got an NS packet, and we don't have that adddress 319 * assigned for us. We MUST silently ignore it. 320 * See RFC2461 7.2.3. 321 */ 322 goto freeit; 323 } 324 myaddr6 = *IFA_IN6(ifa); 325 anycast = ((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_ANYCAST; 326 tentative = ((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_TENTATIVE; 327 if (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_DUPLICATED) 328 goto freeit; 329 330 if (lladdr && ((cmpifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) { 331 nd6log((LOG_INFO, 332 "nd6_ns_input: lladdrlen mismatch for %s " 333 "(if %d, NS packet %d)\n", 334 ip6_sprintf(&taddr6), cmpifp->if_addrlen, lladdrlen - 2)); 335 goto bad; 336 } 337 338 if (IN6_ARE_ADDR_EQUAL(&myaddr6, &saddr6)) { 339 nd6log((LOG_INFO, 340 "nd6_ns_input: duplicate IP6 address %s\n", 341 ip6_sprintf(&saddr6))); 342 goto freeit; 343 } 344 345 /* 346 * We have neighbor solicitation packet, with target address equals to 347 * one of my tentative address. 348 * 349 * src addr how to process? 350 * --- --- 351 * multicast of course, invalid (rejected in ip6_input) 352 * unicast somebody is doing address resolution -> ignore 353 * unspec dup address detection 354 * 355 * The processing is defined in RFC 2462. 356 */ 357 if (tentative) { 358 /* 359 * If source address is unspecified address, it is for 360 * duplicated address detection. 361 * 362 * If not, the packet is for addess resolution; 363 * silently ignore it. 364 */ 365 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) 366 nd6_dad_ns_input(ifa); 367 368 goto freeit; 369 } 370 371 /* 372 * If the source address is unspecified address, entries must not 373 * be created or updated. 374 * It looks that sender is performing DAD. Output NA toward 375 * all-node multicast address, to tell the sender that I'm using 376 * the address. 377 * S bit ("solicited") must be zero. 378 */ 379 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) { 380 saddr6 = kin6addr_linklocal_allnodes; 381 saddr6.s6_addr16[1] = htons(cmpifp->if_index); 382 nd6_na_output(cmpifp, &saddr6, &taddr6, 383 ((anycast || proxy || !tlladdr) 384 ? 0 : ND_NA_FLAG_OVERRIDE) 385 | (ip6_forwarding ? ND_NA_FLAG_ROUTER : 0), 386 tlladdr, (struct sockaddr *)proxydl); 387 goto freeit; 388 } 389 390 nd6_cache_lladdr(cmpifp, &saddr6, lladdr, 391 lladdrlen, ND_NEIGHBOR_SOLICIT, 0); 392 393 nd6_na_output(ifp, &saddr6, &taddr6, 394 ((anycast || proxy || !tlladdr) ? 0 : ND_NA_FLAG_OVERRIDE) 395 | (ip6_forwarding ? ND_NA_FLAG_ROUTER : 0) 396 | ND_NA_FLAG_SOLICITED, 397 tlladdr, (struct sockaddr *)proxydl); 398 freeit: 399 m_freem(m); 400 return; 401 402 bad: 403 nd6log((LOG_ERR, "nd6_ns_input: src=%s\n", ip6_sprintf(&saddr6))); 404 nd6log((LOG_ERR, "nd6_ns_input: dst=%s\n", ip6_sprintf(&daddr6))); 405 nd6log((LOG_ERR, "nd6_ns_input: tgt=%s\n", ip6_sprintf(&taddr6))); 406 icmp6stat.icp6s_badns++; 407 m_freem(m); 408 } 409 410 /* 411 * Output an Neighbor Solicitation Message. Caller specifies: 412 * - ICMP6 header source IP6 address 413 * - ND6 header target IP6 address 414 * - ND6 header source datalink address 415 * 416 * Based on RFC 2461 417 * Based on RFC 2462 (duplicated address detection) 418 */ 419 void 420 nd6_ns_output(struct ifnet *ifp, const struct in6_addr *daddr6, 421 const struct in6_addr *taddr6, 422 struct llinfo_nd6 *ln, /* for source address determination */ 423 int dad) /* duplicated address detection */ 424 { 425 struct mbuf *m; 426 struct ip6_hdr *ip6; 427 struct nd_neighbor_solicit *nd_ns; 428 struct in6_ifaddr *ia = NULL; 429 struct ip6_moptions im6o; 430 int icmp6len; 431 int maxlen; 432 caddr_t mac; 433 struct ifnet *outif = NULL; 434 435 if (IN6_IS_ADDR_MULTICAST(taddr6)) 436 return; 437 438 /* estimate the size of message */ 439 maxlen = sizeof(*ip6) + sizeof(*nd_ns); 440 maxlen += (sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7; 441 if (max_linkhdr + maxlen >= MCLBYTES) { 442 #ifdef DIAGNOSTIC 443 kprintf("nd6_ns_output: max_linkhdr + maxlen >= MCLBYTES " 444 "(%d + %d > %d)\n", max_linkhdr, maxlen, MCLBYTES); 445 #endif 446 return; 447 } 448 449 m = m_getb(max_linkhdr + maxlen, M_NOWAIT, MT_DATA, M_PKTHDR); 450 if (m == NULL) 451 return; 452 453 if (daddr6 == NULL || IN6_IS_ADDR_MULTICAST(daddr6)) { 454 m->m_flags |= M_MCAST; 455 im6o.im6o_multicast_ifp = ifp; 456 im6o.im6o_multicast_hlim = 255; 457 im6o.im6o_multicast_loop = 0; 458 } 459 460 icmp6len = sizeof(*nd_ns); 461 m->m_pkthdr.len = m->m_len = sizeof(*ip6) + icmp6len; 462 m->m_data += max_linkhdr; /* or MH_ALIGN() equivalent? */ 463 464 /* fill neighbor solicitation packet */ 465 ip6 = mtod(m, struct ip6_hdr *); 466 ip6->ip6_flow = 0; 467 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 468 ip6->ip6_vfc |= IPV6_VERSION; 469 /* ip6->ip6_plen will be set later */ 470 ip6->ip6_nxt = IPPROTO_ICMPV6; 471 ip6->ip6_hlim = 255; 472 if (daddr6) 473 ip6->ip6_dst = *daddr6; 474 else { 475 ip6->ip6_dst.s6_addr16[0] = IPV6_ADDR_INT16_MLL; 476 ip6->ip6_dst.s6_addr16[1] = htons(ifp->if_index); 477 ip6->ip6_dst.s6_addr32[1] = 0; 478 ip6->ip6_dst.s6_addr32[2] = IPV6_ADDR_INT32_ONE; 479 ip6->ip6_dst.s6_addr32[3] = taddr6->s6_addr32[3]; 480 ip6->ip6_dst.s6_addr8[12] = 0xff; 481 } 482 if (!dad) { 483 #if 0 /* KAME way, exact address scope match */ 484 /* 485 * Select a source whose scope is the same as that of the dest. 486 * Typically, the dest is link-local solicitation multicast 487 * (i.e. neighbor discovery) or link-local/global unicast 488 * (i.e. neighbor un-reachability detection). 489 */ 490 ia = in6_ifawithifp(ifp, &ip6->ip6_dst); 491 if (ia == NULL) { 492 m_freem(m); 493 return; 494 } 495 ip6->ip6_src = ia->ia_addr.sin6_addr; 496 #else /* spec-wise correct */ 497 /* 498 * RFC2461 7.2.2: 499 * "If the source address of the packet prompting the 500 * solicitation is the same as one of the addresses assigned 501 * to the outgoing interface, that address SHOULD be placed 502 * in the IP Source Address of the outgoing solicitation. 503 * Otherwise, any one of the addresses assigned to the 504 * interface should be used." 505 * 506 * We use the source address for the prompting packet 507 * (saddr6), if: 508 * - saddr6 is given from the caller (by giving "ln"), and 509 * - saddr6 belongs to the outgoing interface. 510 * Otherwise, we perform a scope-wise match. 511 */ 512 struct ip6_hdr *hip6; /* hold ip6 */ 513 struct in6_addr *saddr6; 514 515 if (ln && ln->ln_hold) { 516 hip6 = mtod(ln->ln_hold, struct ip6_hdr *); 517 /* XXX pullup? */ 518 if (sizeof(*hip6) < ln->ln_hold->m_len) 519 saddr6 = &hip6->ip6_src; 520 else 521 saddr6 = NULL; 522 } else 523 saddr6 = NULL; 524 if (saddr6 && in6ifa_ifpwithaddr(ifp, saddr6)) 525 bcopy(saddr6, &ip6->ip6_src, sizeof(*saddr6)); 526 else { 527 ia = in6_ifawithifp(ifp, &ip6->ip6_dst); 528 if (ia == NULL) { 529 m_freem(m); 530 return; 531 } 532 ip6->ip6_src = ia->ia_addr.sin6_addr; 533 } 534 #endif 535 } else { 536 /* 537 * Source address for DAD packet must always be IPv6 538 * unspecified address. (0::0) 539 */ 540 bzero(&ip6->ip6_src, sizeof(ip6->ip6_src)); 541 } 542 nd_ns = (struct nd_neighbor_solicit *)(ip6 + 1); 543 nd_ns->nd_ns_type = ND_NEIGHBOR_SOLICIT; 544 nd_ns->nd_ns_code = 0; 545 nd_ns->nd_ns_reserved = 0; 546 nd_ns->nd_ns_target = *taddr6; 547 548 if (IN6_IS_SCOPE_LINKLOCAL(&nd_ns->nd_ns_target)) 549 nd_ns->nd_ns_target.s6_addr16[1] = 0; 550 551 /* 552 * Add source link-layer address option. 553 * 554 * spec implementation 555 * --- --- 556 * DAD packet MUST NOT do not add the option 557 * there's no link layer address: 558 * impossible do not add the option 559 * there's link layer address: 560 * Multicast NS MUST add one add the option 561 * Unicast NS SHOULD add one add the option 562 */ 563 if (!dad && (mac = nd6_ifptomac(ifp))) { 564 int optlen = sizeof(struct nd_opt_hdr) + ifp->if_addrlen; 565 struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)(nd_ns + 1); 566 /* 8 byte alignments... */ 567 optlen = (optlen + 7) & ~7; 568 569 m->m_pkthdr.len += optlen; 570 m->m_len += optlen; 571 icmp6len += optlen; 572 bzero((caddr_t)nd_opt, optlen); 573 nd_opt->nd_opt_type = ND_OPT_SOURCE_LINKADDR; 574 nd_opt->nd_opt_len = optlen >> 3; 575 bcopy(mac, (caddr_t)(nd_opt + 1), ifp->if_addrlen); 576 } 577 578 ip6->ip6_plen = htons((u_short)icmp6len); 579 nd_ns->nd_ns_cksum = 0; 580 nd_ns->nd_ns_cksum 581 = in6_cksum(m, IPPROTO_ICMPV6, sizeof(*ip6), icmp6len); 582 583 ip6_output(m, NULL, NULL, dad ? IPV6_DADOUTPUT : 0, &im6o, &outif, NULL); 584 if (outif) { 585 icmp6_ifstat_inc(outif, ifs6_out_msg); 586 icmp6_ifstat_inc(outif, ifs6_out_neighborsolicit); 587 } 588 icmp6stat.icp6s_outhist[ND_NEIGHBOR_SOLICIT]++; 589 } 590 591 /* 592 * Neighbor advertisement input handling. 593 * 594 * Based on RFC 2461 595 * Based on RFC 2462 (duplicated address detection) 596 * 597 * the following items are not implemented yet: 598 * - proxy advertisement delay rule (RFC2461 7.2.8, last paragraph, SHOULD) 599 * - anycast advertisement delay rule (RFC2461 7.2.7, SHOULD) 600 */ 601 void 602 nd6_na_input(struct mbuf *m, int off, int icmp6len) 603 { 604 struct ifnet *ifp = m->m_pkthdr.rcvif; 605 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 606 struct nd_neighbor_advert *nd_na; 607 struct in6_addr saddr6 = ip6->ip6_src; 608 struct in6_addr daddr6 = ip6->ip6_dst; 609 struct in6_addr taddr6; 610 int flags; 611 int is_router; 612 int is_solicited; 613 int is_override; 614 char *lladdr = NULL; 615 int lladdrlen = 0; 616 struct ifaddr *ifa; 617 struct llinfo_nd6 *ln; 618 struct rtentry *rt; 619 struct sockaddr_dl *sdl; 620 union nd_opts ndopts; 621 622 if (ip6->ip6_hlim != 255) { 623 nd6log((LOG_ERR, 624 "nd6_na_input: invalid hlim (%d) from %s to %s on %s\n", 625 ip6->ip6_hlim, ip6_sprintf(&ip6->ip6_src), 626 ip6_sprintf(&ip6->ip6_dst), if_name(ifp))); 627 goto bad; 628 } 629 630 #ifndef PULLDOWN_TEST 631 IP6_EXTHDR_CHECK(m, off, icmp6len,); 632 nd_na = (struct nd_neighbor_advert *)((caddr_t)ip6 + off); 633 #else 634 IP6_EXTHDR_GET(nd_na, struct nd_neighbor_advert *, m, off, icmp6len); 635 if (nd_na == NULL) { 636 icmp6stat.icp6s_tooshort++; 637 return; 638 } 639 #endif 640 taddr6 = nd_na->nd_na_target; 641 flags = nd_na->nd_na_flags_reserved; 642 is_router = ((flags & ND_NA_FLAG_ROUTER) != 0); 643 is_solicited = ((flags & ND_NA_FLAG_SOLICITED) != 0); 644 is_override = ((flags & ND_NA_FLAG_OVERRIDE) != 0); 645 646 if (IN6_IS_SCOPE_LINKLOCAL(&taddr6)) 647 taddr6.s6_addr16[1] = htons(ifp->if_index); 648 649 if (IN6_IS_ADDR_MULTICAST(&taddr6)) { 650 nd6log((LOG_ERR, 651 "nd6_na_input: invalid target address %s\n", 652 ip6_sprintf(&taddr6))); 653 goto bad; 654 } 655 if (IN6_IS_ADDR_MULTICAST(&daddr6)) 656 if (is_solicited) { 657 nd6log((LOG_ERR, 658 "nd6_na_input: a solicited adv is multicasted\n")); 659 goto bad; 660 } 661 662 icmp6len -= sizeof(*nd_na); 663 nd6_option_init(nd_na + 1, icmp6len, &ndopts); 664 if (nd6_options(&ndopts) < 0) { 665 nd6log((LOG_INFO, 666 "nd6_na_input: invalid ND option, ignored\n")); 667 /* nd6_options have incremented stats */ 668 goto freeit; 669 } 670 671 if (ndopts.nd_opts_tgt_lladdr) { 672 lladdr = (char *)(ndopts.nd_opts_tgt_lladdr + 1); 673 lladdrlen = ndopts.nd_opts_tgt_lladdr->nd_opt_len << 3; 674 } 675 676 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &taddr6); 677 678 /* 679 * Target address matches one of my interface address. 680 * 681 * If my address is tentative, this means that there's somebody 682 * already using the same address as mine. This indicates DAD failure. 683 * This is defined in RFC 2462. 684 * 685 * Otherwise, process as defined in RFC 2461. 686 */ 687 if (ifa 688 && (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_TENTATIVE)) { 689 nd6_dad_na_input(ifa); 690 goto freeit; 691 } 692 693 /* Just for safety, maybe unnecessary. */ 694 if (ifa) { 695 log(LOG_ERR, 696 "nd6_na_input: duplicate IP6 address %s\n", 697 ip6_sprintf(&taddr6)); 698 goto freeit; 699 } 700 701 /* 702 * Make sure the source address is from a neighbor's address. 703 */ 704 if (in6ifa_ifplocaladdr(ifp, &saddr6) == NULL) { 705 nd6log((LOG_INFO, "nd6_na_input: " 706 "NA packet from non-neighbor\n")); 707 goto bad; 708 } 709 710 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) { 711 nd6log((LOG_INFO, 712 "nd6_na_input: lladdrlen mismatch for %s " 713 "(if %d, NA packet %d)\n", 714 ip6_sprintf(&taddr6), ifp->if_addrlen, lladdrlen - 2)); 715 goto bad; 716 } 717 718 /* 719 * If no neighbor cache entry is found, NA SHOULD silently be discarded. 720 */ 721 rt = nd6_lookup(&taddr6, 0, ifp); 722 if ((rt == NULL) || 723 ((ln = (struct llinfo_nd6 *)rt->rt_llinfo) == NULL) || 724 ((sdl = SDL(rt->rt_gateway)) == NULL)) 725 goto freeit; 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) 733 goto freeit; 734 735 /* 736 * Record link-layer address, and update the state. 737 */ 738 sdl->sdl_alen = ifp->if_addrlen; 739 bcopy(lladdr, LLADDR(sdl), ifp->if_addrlen); 740 if (is_solicited) { 741 ln->ln_state = ND6_LLINFO_REACHABLE; 742 ln->ln_byhint = 0; 743 if (ln->ln_expire) 744 ln->ln_expire = time_uptime + 745 ND_IFINFO(rt->rt_ifp)->reachable; 746 } else { 747 ln->ln_state = ND6_LLINFO_STALE; 748 ln->ln_expire = time_uptime + nd6_gctimer; 749 } 750 if ((ln->ln_router = is_router) != 0) { 751 /* 752 * This means a router's state has changed from 753 * non-reachable to probably reachable, and might 754 * affect the status of associated prefixes.. 755 */ 756 pfxlist_onlink_check(); 757 } 758 } else { 759 int llchange; 760 761 /* 762 * Check if the link-layer address has changed or not. 763 */ 764 if (!lladdr) 765 llchange = 0; 766 else { 767 if (sdl->sdl_alen) { 768 if (bcmp(lladdr, LLADDR(sdl), ifp->if_addrlen)) 769 llchange = 1; 770 else 771 llchange = 0; 772 } else 773 llchange = 1; 774 } 775 776 /* 777 * This is VERY complex. Look at it with care. 778 * 779 * override solicit lladdr llchange action 780 * (L: record lladdr) 781 * 782 * 0 0 n -- (2c) 783 * 0 0 y n (2b) L 784 * 0 0 y y (1) REACHABLE->STALE 785 * 0 1 n -- (2c) *->REACHABLE 786 * 0 1 y n (2b) L *->REACHABLE 787 * 0 1 y y (1) REACHABLE->STALE 788 * 1 0 n -- (2a) 789 * 1 0 y n (2a) L 790 * 1 0 y y (2a) L *->STALE 791 * 1 1 n -- (2a) *->REACHABLE 792 * 1 1 y n (2a) L *->REACHABLE 793 * 1 1 y y (2a) L *->REACHABLE 794 */ 795 if (!is_override && (lladdr && llchange)) { /* (1) */ 796 /* 797 * If state is REACHABLE, make it STALE. 798 * no other updates should be done. 799 */ 800 if (ln->ln_state == ND6_LLINFO_REACHABLE) { 801 ln->ln_state = ND6_LLINFO_STALE; 802 ln->ln_expire = time_uptime + nd6_gctimer; 803 } 804 goto freeit; 805 } else if (is_override /* (2a) */ 806 || (!is_override && (lladdr && !llchange)) /* (2b) */ 807 || !lladdr) { /* (2c) */ 808 /* 809 * Update link-local address, if any. 810 */ 811 if (lladdr) { 812 sdl->sdl_alen = ifp->if_addrlen; 813 bcopy(lladdr, LLADDR(sdl), ifp->if_addrlen); 814 } 815 816 /* 817 * If solicited, make the state REACHABLE. 818 * If not solicited and the link-layer address was 819 * changed, make it STALE. 820 */ 821 if (is_solicited) { 822 ln->ln_state = ND6_LLINFO_REACHABLE; 823 ln->ln_byhint = 0; 824 if (ln->ln_expire) { 825 ln->ln_expire = time_uptime + 826 ND_IFINFO(ifp)->reachable; 827 } 828 } else { 829 if (lladdr && llchange) { 830 ln->ln_state = ND6_LLINFO_STALE; 831 ln->ln_expire = time_uptime + nd6_gctimer; 832 } 833 } 834 } 835 836 if (ln->ln_router && !is_router) { 837 /* 838 * The peer dropped the router flag. 839 * Remove the sender from the Default Router List and 840 * update the Destination Cache entries. 841 */ 842 struct nd_defrouter *dr; 843 struct in6_addr *in6; 844 845 in6 = &((struct sockaddr_in6 *)rt_key(rt))->sin6_addr; 846 847 /* 848 * Lock to protect the default router list. 849 * XXX: this might be unnecessary, since this function 850 * is only called under the network software interrupt 851 * context. However, we keep it just for safety. 852 */ 853 mtx_lock(&nd6_mtx); 854 dr = defrouter_lookup(in6, rt->rt_ifp); 855 if (dr) 856 defrtrlist_del(dr); 857 mtx_unlock(&nd6_mtx); 858 859 if (dr == NULL && !ip6_forwarding && ip6_accept_rtadv) { 860 /* 861 * Even if the neighbor is not in the default 862 * router list, the neighbor may be used 863 * as a next hop for some destinations 864 * (e.g. redirect case). So we must 865 * call rt6_flush explicitly. 866 */ 867 rt6_flush(&ip6->ip6_src, rt->rt_ifp); 868 } 869 } 870 ln->ln_router = is_router; 871 } 872 rt->rt_flags &= ~RTF_REJECT; 873 ln->ln_asked = 0; 874 if (ln->ln_hold) { 875 /* 876 * we assume ifp is not a loopback here, so just set the 2nd 877 * argument as the 1st one. 878 */ 879 nd6_output(ifp, ifp, ln->ln_hold, 880 (struct sockaddr_in6 *)rt_key(rt), rt); 881 ln->ln_hold = 0; 882 } 883 884 freeit: 885 m_freem(m); 886 return; 887 888 bad: 889 icmp6stat.icp6s_badna++; 890 m_freem(m); 891 } 892 893 /* 894 * Neighbor advertisement output handling. 895 * 896 * Based on RFC 2461 897 * 898 * the following items are not implemented yet: 899 * - proxy advertisement delay rule (RFC2461 7.2.8, last paragraph, SHOULD) 900 * - anycast advertisement delay rule (RFC2461 7.2.7, SHOULD) 901 */ 902 void 903 nd6_na_output(struct ifnet *ifp, const struct in6_addr *daddr6, 904 const struct in6_addr *taddr6, u_long flags, 905 int tlladdr, /* 1 if include target link-layer address */ 906 struct sockaddr *sdl0) /* sockaddr_dl (= proxy NA) or NULL */ 907 { 908 struct mbuf *m; 909 struct ip6_hdr *ip6; 910 struct nd_neighbor_advert *nd_na; 911 struct in6_ifaddr *ia = NULL; 912 struct ip6_moptions im6o; 913 int icmp6len; 914 int maxlen; 915 caddr_t mac; 916 struct ifnet *outif = NULL; 917 918 /* estimate the size of message */ 919 maxlen = sizeof(*ip6) + sizeof(*nd_na); 920 maxlen += (sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7; 921 if (max_linkhdr + maxlen >= MCLBYTES) { 922 #ifdef DIAGNOSTIC 923 kprintf("nd6_na_output: max_linkhdr + maxlen >= MCLBYTES " 924 "(%d + %d > %d)\n", max_linkhdr, maxlen, MCLBYTES); 925 #endif 926 return; 927 } 928 929 m = m_getb(max_linkhdr + maxlen, M_NOWAIT, MT_DATA, M_PKTHDR); 930 if (m == NULL) 931 return; 932 933 if (IN6_IS_ADDR_MULTICAST(daddr6)) { 934 m->m_flags |= M_MCAST; 935 im6o.im6o_multicast_ifp = ifp; 936 im6o.im6o_multicast_hlim = 255; 937 im6o.im6o_multicast_loop = 0; 938 } 939 940 icmp6len = sizeof(*nd_na); 941 m->m_pkthdr.len = m->m_len = sizeof(struct ip6_hdr) + icmp6len; 942 m->m_data += max_linkhdr; /* or MH_ALIGN() equivalent? */ 943 944 /* fill neighbor advertisement packet */ 945 ip6 = mtod(m, struct ip6_hdr *); 946 ip6->ip6_flow = 0; 947 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 948 ip6->ip6_vfc |= IPV6_VERSION; 949 ip6->ip6_nxt = IPPROTO_ICMPV6; 950 ip6->ip6_hlim = 255; 951 if (IN6_IS_ADDR_UNSPECIFIED(daddr6)) { 952 /* reply to DAD */ 953 ip6->ip6_dst.s6_addr16[0] = IPV6_ADDR_INT16_MLL; 954 ip6->ip6_dst.s6_addr16[1] = htons(ifp->if_index); 955 ip6->ip6_dst.s6_addr32[1] = 0; 956 ip6->ip6_dst.s6_addr32[2] = 0; 957 ip6->ip6_dst.s6_addr32[3] = IPV6_ADDR_INT32_ONE; 958 flags &= ~ND_NA_FLAG_SOLICITED; 959 } else 960 ip6->ip6_dst = *daddr6; 961 962 /* 963 * Select a source whose scope is the same as that of the dest. 964 */ 965 ia = in6_ifawithifp(ifp, &ip6->ip6_dst); 966 if (ia == NULL) { 967 m_freem(m); 968 return; 969 } 970 ip6->ip6_src = ia->ia_addr.sin6_addr; 971 nd_na = (struct nd_neighbor_advert *)(ip6 + 1); 972 nd_na->nd_na_type = ND_NEIGHBOR_ADVERT; 973 nd_na->nd_na_code = 0; 974 nd_na->nd_na_target = *taddr6; 975 if (IN6_IS_SCOPE_LINKLOCAL(&nd_na->nd_na_target)) 976 nd_na->nd_na_target.s6_addr16[1] = 0; 977 978 /* 979 * "tlladdr" indicates NS's condition for adding tlladdr or not. 980 * see nd6_ns_input() for details. 981 * Basically, if NS packet is sent to unicast/anycast addr, 982 * target lladdr option SHOULD NOT be included. 983 */ 984 mac = NULL; 985 if (tlladdr) { 986 /* 987 * sdl0 != NULL indicates proxy NA. If we do proxy, use 988 * lladdr in sdl0. If we are not proxying (sending NA for 989 * my address) use lladdr configured for the interface. 990 */ 991 if (sdl0 == NULL) { 992 #ifdef CARP 993 if (ifp->if_carp) 994 mac = carp_macmatch6(ifp->if_carp, m, taddr6); 995 if (mac == NULL) 996 mac = nd6_ifptomac(ifp); 997 #else 998 mac = nd6_ifptomac(ifp); 999 #endif 1000 } else if (sdl0->sa_family == AF_LINK) { 1001 struct sockaddr_dl *sdl; 1002 sdl = (struct sockaddr_dl *)sdl0; 1003 if (sdl->sdl_alen == ifp->if_addrlen) 1004 mac = LLADDR(sdl); 1005 } 1006 } 1007 if (mac != NULL) { 1008 int optlen = sizeof(struct nd_opt_hdr) + ifp->if_addrlen; 1009 struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)(nd_na + 1); 1010 1011 /* roundup to 8 bytes alignment! */ 1012 optlen = (optlen + 7) & ~7; 1013 1014 m->m_pkthdr.len += optlen; 1015 m->m_len += optlen; 1016 icmp6len += optlen; 1017 bzero((caddr_t)nd_opt, optlen); 1018 nd_opt->nd_opt_type = ND_OPT_TARGET_LINKADDR; 1019 nd_opt->nd_opt_len = optlen >> 3; 1020 bcopy(mac, (caddr_t)(nd_opt + 1), ifp->if_addrlen); 1021 } else 1022 flags &= ~ND_NA_FLAG_OVERRIDE; 1023 1024 ip6->ip6_plen = htons((u_short)icmp6len); 1025 nd_na->nd_na_flags_reserved = flags; 1026 nd_na->nd_na_cksum = 0; 1027 nd_na->nd_na_cksum = 1028 in6_cksum(m, IPPROTO_ICMPV6, sizeof(struct ip6_hdr), icmp6len); 1029 1030 ip6_output(m, NULL, NULL, 0, &im6o, &outif, NULL); 1031 if (outif) { 1032 icmp6_ifstat_inc(outif, ifs6_out_msg); 1033 icmp6_ifstat_inc(outif, ifs6_out_neighboradvert); 1034 } 1035 icmp6stat.icp6s_outhist[ND_NEIGHBOR_ADVERT]++; 1036 } 1037 1038 caddr_t 1039 nd6_ifptomac(struct ifnet *ifp) 1040 { 1041 switch (ifp->if_type) { 1042 case IFT_ETHER: 1043 case IFT_IEEE1394: 1044 #ifdef IFT_L2VLAN 1045 case IFT_L2VLAN: 1046 #endif 1047 #ifdef IFT_IEEE80211 1048 case IFT_IEEE80211: 1049 #endif 1050 #ifdef IFT_CARP 1051 case IFT_CARP: 1052 #endif 1053 return ((caddr_t)(ifp + 1)); 1054 break; 1055 default: 1056 return NULL; 1057 } 1058 } 1059 1060 struct netmsg_dad { 1061 struct netmsg_base base; 1062 struct dadq *dadq; 1063 }; 1064 1065 struct dadq { 1066 TAILQ_ENTRY(dadq) dad_list; 1067 struct ifaddr *dad_ifa; 1068 int dad_count; /* max NS to send */ 1069 int dad_ns_tcount; /* # of trials to send NS */ 1070 int dad_ns_ocount; /* NS sent so far */ 1071 int dad_ns_icount; 1072 int dad_na_icount; 1073 struct callout dad_timer_ch; 1074 struct netmsg_dad dad_nmsg; 1075 }; 1076 TAILQ_HEAD(dadq_head, dadq); 1077 1078 static struct dadq_head dadq = TAILQ_HEAD_INITIALIZER(dadq); 1079 1080 static struct dadq * 1081 nd6_dad_find(struct ifaddr *ifa) 1082 { 1083 struct dadq *dp; 1084 1085 ASSERT_IN_NETISR(0); 1086 1087 TAILQ_FOREACH(dp, &dadq, dad_list) { 1088 if (dp->dad_ifa == ifa) 1089 return dp; 1090 } 1091 return NULL; 1092 } 1093 1094 static void 1095 nd6_dad_starttimer(struct dadq *dp, int ticks) 1096 { 1097 ASSERT_IN_NETISR(0); 1098 callout_reset(&dp->dad_timer_ch, ticks, nd6_dad_timer, dp); 1099 } 1100 1101 static void 1102 nd6_dad_stoptimer(struct dadq *dp) 1103 { 1104 ASSERT_IN_NETISR(0); 1105 callout_stop(&dp->dad_timer_ch); 1106 } 1107 1108 /* 1109 * Start Duplicated Address Detection (DAD) for specified interface address. 1110 */ 1111 void 1112 nd6_dad_start(struct ifaddr *ifa, 1113 int *tick) /* minimum delay ticks for IFF_UP event */ 1114 { 1115 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1116 struct dadq *dp; 1117 1118 ASSERT_IN_NETISR(0); 1119 1120 /* 1121 * If we don't need DAD, don't do it. 1122 * There are several cases: 1123 * - DAD is disabled (ip6_dad_count == 0) 1124 * - the interface address is anycast 1125 */ 1126 if (!(ia->ia6_flags & IN6_IFF_TENTATIVE)) { 1127 log(LOG_DEBUG, 1128 "nd6_dad_start: called with non-tentative address " 1129 "%s(%s)\n", 1130 ip6_sprintf(&ia->ia_addr.sin6_addr), 1131 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1132 return; 1133 } 1134 if (ia->ia6_flags & IN6_IFF_ANYCAST) { 1135 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1136 return; 1137 } 1138 if (!ip6_dad_count) { 1139 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1140 return; 1141 } 1142 if (!ifa->ifa_ifp) 1143 panic("nd6_dad_start: ifa->ifa_ifp == NULL"); 1144 if (!(ifa->ifa_ifp->if_flags & IFF_UP)) 1145 return; 1146 if (nd6_dad_find(ifa) != NULL) { 1147 /* DAD already in progress */ 1148 return; 1149 } 1150 1151 dp = nd6_dad_create(ifa); 1152 nd6log((LOG_DEBUG, "%s: starting DAD for %s\n", if_name(ifa->ifa_ifp), 1153 ip6_sprintf(&ia->ia_addr.sin6_addr))); 1154 1155 /* 1156 * Send NS packet for DAD, dp->dad_count times. 1157 * Note that we must delay the first transmission, if this is the 1158 * first packet to be sent from the interface after interface 1159 * (re)initialization. 1160 */ 1161 if (tick == NULL) { 1162 nd6_dad_ns_output(dp); 1163 nd6_dad_starttimer(dp, 1164 ND_IFINFO(ifa->ifa_ifp)->retrans * hz / 1000); 1165 } else { 1166 int ntick; 1167 1168 if (*tick == 0) 1169 ntick = krandom() % (MAX_RTR_SOLICITATION_DELAY * hz); 1170 else 1171 ntick = *tick + krandom() % (hz / 2); 1172 *tick = ntick; 1173 nd6_dad_starttimer(dp, ntick); 1174 } 1175 } 1176 1177 /* 1178 * Terminate DAD unconditionally. Used for address removals. 1179 */ 1180 void 1181 nd6_dad_stop(struct ifaddr *ifa) 1182 { 1183 struct dadq *dp; 1184 1185 ASSERT_IN_NETISR(0); 1186 1187 dp = nd6_dad_find(ifa); 1188 if (!dp) { 1189 /* DAD wasn't started yet */ 1190 return; 1191 } 1192 nd6_dad_destroy(dp); 1193 } 1194 1195 static struct dadq * 1196 nd6_dad_create(struct ifaddr *ifa) 1197 { 1198 struct netmsg_dad *dm; 1199 struct dadq *dp; 1200 1201 ASSERT_IN_NETISR(0); 1202 1203 dp = kmalloc(sizeof(*dp), M_IP6NDP, M_INTWAIT | M_ZERO); 1204 callout_init_mp(&dp->dad_timer_ch); 1205 1206 dm = &dp->dad_nmsg; 1207 netmsg_init(&dm->base, NULL, &netisr_adone_rport, 1208 MSGF_DROPABLE | MSGF_PRIORITY, nd6_dad_timer_handler); 1209 dm->dadq = dp; 1210 1211 dp->dad_ifa = ifa; 1212 IFAREF(ifa); /* just for safety */ 1213 1214 /* Send NS packet for DAD, ip6_dad_count times. */ 1215 dp->dad_count = ip6_dad_count; 1216 1217 TAILQ_INSERT_TAIL(&dadq, dp, dad_list); 1218 1219 return dp; 1220 } 1221 1222 static void 1223 nd6_dad_destroy(struct dadq *dp) 1224 { 1225 struct lwkt_msg *lmsg = &dp->dad_nmsg.base.lmsg; 1226 1227 ASSERT_IN_NETISR(0); 1228 1229 TAILQ_REMOVE(&dadq, dp, dad_list); 1230 1231 nd6_dad_stoptimer(dp); 1232 1233 crit_enter(); 1234 if ((lmsg->ms_flags & MSGF_DONE) == 0) 1235 lwkt_dropmsg(lmsg); 1236 crit_exit(); 1237 1238 IFAFREE(dp->dad_ifa); 1239 kfree(dp, M_IP6NDP); 1240 } 1241 1242 static void 1243 nd6_dad_timer(void *xdp) 1244 { 1245 struct dadq *dp = xdp; 1246 struct lwkt_msg *lmsg = &dp->dad_nmsg.base.lmsg; 1247 1248 KASSERT(mycpuid == 0, ("dad timer not on cpu0")); 1249 1250 crit_enter(); 1251 if (lmsg->ms_flags & MSGF_DONE) 1252 lwkt_sendmsg_oncpu(netisr_cpuport(0), lmsg); 1253 crit_exit(); 1254 } 1255 1256 static void 1257 nd6_dad_timer_handler(netmsg_t msg) 1258 { 1259 struct netmsg_dad *dm = (struct netmsg_dad *)msg; 1260 struct dadq *dp = dm->dadq; 1261 struct ifaddr *ifa = dp->dad_ifa; 1262 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1263 1264 ASSERT_IN_NETISR(0); 1265 1266 /* Reply ASAP */ 1267 crit_enter(); 1268 lwkt_replymsg(&dm->base.lmsg, 0); 1269 crit_exit(); 1270 1271 if (ia->ia6_flags & IN6_IFF_DUPLICATED) { 1272 log(LOG_ERR, "nd6_dad_timer: called with duplicated address " 1273 "%s(%s)\n", 1274 ip6_sprintf(&ia->ia_addr.sin6_addr), 1275 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1276 goto destroy; 1277 } 1278 if (!(ia->ia6_flags & IN6_IFF_TENTATIVE)) { 1279 log(LOG_ERR, "nd6_dad_timer: called with non-tentative address " 1280 "%s(%s)\n", 1281 ip6_sprintf(&ia->ia_addr.sin6_addr), 1282 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1283 goto destroy; 1284 } 1285 1286 /* Timed out with IFF_{RUNNING,UP} check */ 1287 if (dp->dad_ns_tcount > dad_maxtry) { 1288 nd6log((LOG_INFO, "%s: could not run DAD, driver problem?\n", 1289 if_name(ifa->ifa_ifp))); 1290 goto destroy; 1291 } 1292 1293 /* Need more checks? */ 1294 if (dp->dad_ns_ocount < dp->dad_count) { 1295 /* 1296 * We have more NS to go. Send NS packet for DAD. 1297 */ 1298 nd6_dad_ns_output(dp); 1299 nd6_dad_starttimer(dp, 1300 ND_IFINFO(ifa->ifa_ifp)->retrans * hz / 1000); 1301 } else { 1302 /* 1303 * We have transmitted sufficient number of DAD packets. 1304 * See what we've got. 1305 */ 1306 int duplicate; 1307 1308 duplicate = 0; 1309 1310 if (dp->dad_na_icount) { 1311 /* 1312 * the check is in nd6_dad_na_input(), 1313 * but just in case 1314 */ 1315 duplicate++; 1316 } 1317 1318 if (dp->dad_ns_icount) { 1319 #if 0 /* heuristics */ 1320 /* 1321 * if 1322 * - we have sent many(?) DAD NS, and 1323 * - the number of NS we sent equals to the 1324 * number of NS we've got, and 1325 * - we've got no NA 1326 * we may have a faulty network card/driver which 1327 * loops back multicasts to myself. 1328 */ 1329 if (3 < dp->dad_count 1330 && dp->dad_ns_icount == dp->dad_count 1331 && dp->dad_na_icount == 0) { 1332 log(LOG_INFO, "DAD questionable for %s(%s): " 1333 "network card loops back multicast?\n", 1334 ip6_sprintf(&ia->ia_addr.sin6_addr), 1335 if_name(ifa->ifa_ifp)); 1336 /* XXX consider it a duplicate or not? */ 1337 /* duplicate++; */ 1338 } else { 1339 /* We've seen NS, means DAD has failed. */ 1340 duplicate++; 1341 } 1342 #else 1343 /* We've seen NS, means DAD has failed. */ 1344 duplicate++; 1345 #endif 1346 } 1347 1348 if (duplicate) { 1349 /* dp will be freed in nd6_dad_duplicated() */ 1350 dp = NULL; 1351 nd6_dad_duplicated(ifa); 1352 } else { 1353 /* 1354 * We are done with DAD. No NA came, no NS came. 1355 * duplicated address found. 1356 */ 1357 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1358 nd6log((LOG_DEBUG, 1359 "%s: DAD complete for %s - no duplicates found\n", 1360 if_name(ifa->ifa_ifp), 1361 ip6_sprintf(&ia->ia_addr.sin6_addr))); 1362 goto destroy; 1363 } 1364 } 1365 return; 1366 destroy: 1367 nd6_dad_destroy(dp); 1368 } 1369 1370 static void 1371 nd6_dad_duplicated(struct ifaddr *ifa) 1372 { 1373 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1374 struct dadq *dp; 1375 1376 ASSERT_IN_NETISR(0); 1377 1378 dp = nd6_dad_find(ifa); 1379 if (dp == NULL) { 1380 log(LOG_ERR, "nd6_dad_duplicated: DAD structure not found\n"); 1381 return; 1382 } 1383 1384 /* 1385 * We are done with DAD, with duplicated address found. (failure) 1386 */ 1387 log(LOG_ERR, "%s: DAD detected duplicate IPv6 address %s: " 1388 "NS in/out=%d/%d, NA in=%d\n", 1389 if_name(ifa->ifa_ifp), ip6_sprintf(&ia->ia_addr.sin6_addr), 1390 dp->dad_ns_icount, dp->dad_ns_ocount, dp->dad_na_icount); 1391 1392 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1393 ia->ia6_flags |= IN6_IFF_DUPLICATED; 1394 1395 log(LOG_ERR, "%s: DAD complete for %s - duplicate found\n", 1396 if_name(ifa->ifa_ifp), ip6_sprintf(&ia->ia_addr.sin6_addr)); 1397 log(LOG_ERR, "%s: manual intervention required\n", 1398 if_name(ifa->ifa_ifp)); 1399 1400 nd6_dad_destroy(dp); 1401 } 1402 1403 static void 1404 nd6_dad_ns_output(struct dadq *dp) 1405 { 1406 struct in6_ifaddr *ia = (struct in6_ifaddr *)dp->dad_ifa; 1407 struct ifnet *ifp = dp->dad_ifa->ifa_ifp; 1408 1409 ASSERT_IN_NETISR(0); 1410 1411 dp->dad_ns_tcount++; 1412 if (!(ifp->if_flags & IFF_UP)) { 1413 #if 0 1414 kprintf("%s: interface down?\n", if_name(ifp)); 1415 #endif 1416 return; 1417 } 1418 if (!(ifp->if_flags & IFF_RUNNING)) { 1419 #if 0 1420 kprintf("%s: interface not running?\n", if_name(ifp)); 1421 #endif 1422 return; 1423 } 1424 1425 dp->dad_ns_ocount++; 1426 nd6_ns_output(ifp, NULL, &ia->ia_addr.sin6_addr, NULL, 1); 1427 } 1428 1429 static void 1430 nd6_dad_ns_input(struct ifaddr *ifa) 1431 { 1432 struct in6_ifaddr *ia; 1433 const struct in6_addr *taddr6; 1434 struct dadq *dp; 1435 int duplicate; 1436 1437 ASSERT_IN_NETISR(0); 1438 1439 if (!ifa) 1440 panic("ifa == NULL in nd6_dad_ns_input"); 1441 1442 ia = (struct in6_ifaddr *)ifa; 1443 taddr6 = &ia->ia_addr.sin6_addr; 1444 duplicate = 0; 1445 dp = nd6_dad_find(ifa); 1446 1447 /* Quickhack - completely ignore DAD NS packets */ 1448 if (dad_ignore_ns) { 1449 nd6log((LOG_INFO, 1450 "nd6_dad_ns_input: ignoring DAD NS packet for " 1451 "address %s(%s)\n", ip6_sprintf(taddr6), 1452 if_name(ifa->ifa_ifp))); 1453 return; 1454 } 1455 1456 /* 1457 * if I'm yet to start DAD, someone else started using this address 1458 * first. I have a duplicate and you win. 1459 */ 1460 if (!dp || dp->dad_ns_ocount == 0) 1461 duplicate++; 1462 1463 /* XXX more checks for loopback situation - see nd6_dad_timer too */ 1464 1465 if (duplicate) { 1466 dp = NULL; /* will be freed in nd6_dad_duplicated() */ 1467 nd6_dad_duplicated(ifa); 1468 } else { 1469 /* 1470 * not sure if I got a duplicate. 1471 * increment ns count and see what happens. 1472 */ 1473 if (dp) 1474 dp->dad_ns_icount++; 1475 } 1476 } 1477 1478 static void 1479 nd6_dad_na_input(struct ifaddr *ifa) 1480 { 1481 struct dadq *dp; 1482 1483 ASSERT_IN_NETISR(0); 1484 1485 if (!ifa) 1486 panic("ifa == NULL in nd6_dad_na_input"); 1487 1488 dp = nd6_dad_find(ifa); 1489 if (dp) 1490 dp->dad_na_icount++; 1491 1492 /* remove the address. */ 1493 nd6_dad_duplicated(ifa); 1494 } 1495