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_carp.h" 36 37 #include <sys/param.h> 38 #include <sys/systm.h> 39 #include <sys/malloc.h> 40 #include <sys/mbuf.h> 41 #include <sys/socket.h> 42 #include <sys/sockio.h> 43 #include <sys/time.h> 44 #include <sys/kernel.h> 45 #include <sys/errno.h> 46 #include <sys/syslog.h> 47 #include <sys/queue.h> 48 #include <sys/callout.h> 49 #include <sys/mutex.h> 50 51 #include <sys/thread2.h> 52 #include <sys/mutex2.h> 53 54 #include <net/if.h> 55 #include <net/if_types.h> 56 #include <net/if_dl.h> 57 #include <net/route.h> 58 #include <net/netisr2.h> 59 #include <net/netmsg2.h> 60 61 #include <netinet/in.h> 62 #include <netinet/in_var.h> 63 #include <netinet6/in6_var.h> 64 #include <netinet/ip6.h> 65 #include <netinet6/ip6_var.h> 66 #include <netinet6/nd6.h> 67 #include <netinet/icmp6.h> 68 69 #include <net/net_osdep.h> 70 71 #ifdef CARP 72 #include <netinet/ip_carp.h> 73 #endif 74 75 76 #define SDL(s) ((struct sockaddr_dl *)s) 77 78 struct dadq; 79 static struct dadq *nd6_dad_find(struct ifaddr *); 80 static void nd6_dad_starttimer(struct dadq *, int); 81 static void nd6_dad_stoptimer(struct dadq *); 82 static void nd6_dad_timer(void *); 83 static void nd6_dad_timer_handler(netmsg_t); 84 static void nd6_dad_ns_output(struct dadq *); 85 static void nd6_dad_ns_input(struct ifaddr *); 86 static void nd6_dad_na_input(struct ifaddr *); 87 static struct dadq *nd6_dad_create(struct ifaddr *); 88 static void nd6_dad_destroy(struct dadq *); 89 static void nd6_dad_duplicated(struct ifaddr *); 90 91 static int dad_ignore_ns = 0; /* ignore NS in DAD - specwise incorrect*/ 92 static int dad_maxtry = 15; /* max # of *tries* to transmit DAD packet */ 93 94 /* 95 * Input an Neighbor Solicitation Message. 96 * 97 * Based on RFC 2461 98 * Based on RFC 2462 (duplicated address detection) 99 */ 100 void 101 nd6_ns_input(struct mbuf *m, int off, int icmp6len) 102 { 103 struct ifnet *ifp = m->m_pkthdr.rcvif; 104 struct ifnet *cmpifp; 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 = NULL; 118 119 /* 120 * Collapse interfaces to the bridge for comparison and 121 * mac (llinfo) purposes. 122 */ 123 cmpifp = ifp; 124 if (ifp->if_bridge) 125 cmpifp = ifp->if_bridge; 126 127 #ifndef PULLDOWN_TEST 128 IP6_EXTHDR_CHECK(m, off, icmp6len,); 129 nd_ns = (struct nd_neighbor_solicit *)((caddr_t)ip6 + off); 130 #else 131 IP6_EXTHDR_GET(nd_ns, struct nd_neighbor_solicit *, m, off, icmp6len); 132 if (nd_ns == NULL) { 133 icmp6stat.icp6s_tooshort++; 134 return; 135 } 136 #endif 137 ip6 = mtod(m, struct ip6_hdr *); /* adjust pointer for safety */ 138 taddr6 = nd_ns->nd_ns_target; 139 140 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(&ip6->ip6_src), 144 ip6_sprintf(&ip6->ip6_dst), if_name(ifp))); 145 goto bad; 146 } 147 148 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) { 149 /* dst has to be 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 (!nd6_onlink_ns_rfc4861) { 162 /* 163 * Make sure the source address is from a neighbor's address. 164 * 165 * XXX probably only need to check cmpifp. 166 */ 167 if (in6ifa_ifplocaladdr(cmpifp, &saddr6) == NULL && 168 in6ifa_ifplocaladdr(ifp, &saddr6) == NULL) { 169 nd6log((LOG_INFO, "nd6_ns_input: " 170 "NS packet from non-neighbor\n")); 171 goto bad; 172 } 173 } 174 175 if (IN6_IS_ADDR_MULTICAST(&taddr6)) { 176 nd6log((LOG_INFO, "nd6_ns_input: bad NS target (multicast)\n")); 177 goto bad; 178 } 179 180 if (IN6_IS_SCOPE_LINKLOCAL(&taddr6)) 181 taddr6.s6_addr16[1] = htons(ifp->if_index); 182 183 icmp6len -= sizeof(*nd_ns); 184 nd6_option_init(nd_ns + 1, icmp6len, &ndopts); 185 if (nd6_options(&ndopts) < 0) { 186 nd6log((LOG_INFO, 187 "nd6_ns_input: invalid ND option, ignored\n")); 188 /* nd6_options have incremented stats */ 189 goto freeit; 190 } 191 192 if (ndopts.nd_opts_src_lladdr) { 193 lladdr = (char *)(ndopts.nd_opts_src_lladdr + 1); 194 lladdrlen = ndopts.nd_opts_src_lladdr->nd_opt_len << 3; 195 } 196 197 if (IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_src) && lladdr) { 198 nd6log((LOG_INFO, "nd6_ns_input: bad DAD packet " 199 "(link-layer address option)\n")); 200 goto bad; 201 } 202 203 /* 204 * Attaching target link-layer address to the NA? 205 * (RFC 2461 7.2.4) 206 * 207 * NS IP dst is unicast/anycast MUST NOT add 208 * NS IP dst is solicited-node multicast MUST add 209 * 210 * In implementation, we add target link-layer address by default. 211 * We do not add one in MUST NOT cases. 212 */ 213 #if 0 /* too much! */ 214 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &daddr6); 215 if (ifa && (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_ANYCAST)) 216 tlladdr = 0; 217 else 218 #endif 219 if (!IN6_IS_ADDR_MULTICAST(&daddr6)) 220 tlladdr = 0; 221 else 222 tlladdr = 1; 223 224 /* 225 * Target address (taddr6) must be either: 226 * (1) Valid unicast/anycast address for my receiving interface. 227 * (2) Unicast or anycast address for which I'm offering proxy 228 * service. 229 * (3) "tentative" address on which DAD is being performed. 230 */ 231 /* (1) and (3) check. */ 232 #ifdef CARP 233 if (ifp->if_carp) 234 ifa = carp_iamatch6(ifp->if_carp, &taddr6); 235 if (!ifa) 236 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &taddr6); 237 #else 238 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &taddr6); 239 #endif 240 241 /* 242 * (2) Check proxying. Requires ip6_forwarding to be turned on. 243 * 244 * If the packet is anycast the target route must be on a 245 * different interface because the anycast will get anything 246 * on the current interface. 247 * 248 * If the packet is unicast the target route may be on the 249 * same interface. If the gateway is a (typically manually 250 * configured) link address we can directly offer it. 251 * XXX for now we don't do this but instead offer ours and 252 * presumably relay. 253 * 254 * WARNING! Since this is a subnet proxy the interface proxying 255 * the ND6 must be in promiscuous mode or it will not see the 256 * solicited multicast requests for various hosts being proxied. 257 * 258 * WARNING! Since this is a subnet proxy we have to treat bridge 259 * interfaces as being the bridge itself so we do not proxy-nd6 260 * between bridge interfaces (which are effectively switched). 261 * 262 * (In the specific-host-proxy case via RTF_ANNOUNCE, which is 263 * a bitch to configure, a specific multicast route is already 264 * added for that host <-- NOT RECOMMENDED). 265 */ 266 if (!ifa && ip6_forwarding) { 267 struct rtentry *rt; 268 struct sockaddr_in6 tsin6; 269 struct ifnet *rtifp; 270 271 bzero(&tsin6, sizeof tsin6); 272 tsin6.sin6_len = sizeof(struct sockaddr_in6); 273 tsin6.sin6_family = AF_INET6; 274 tsin6.sin6_addr = taddr6; 275 276 rt = rtpurelookup((struct sockaddr *)&tsin6); 277 rtifp = rt ? rt->rt_ifp : NULL; 278 if (rtifp && rtifp->if_bridge) 279 rtifp = rtifp->if_bridge; 280 281 if (rt != NULL && 282 (cmpifp != rtifp || (m->m_flags & M_MCAST) == 0)) { 283 ifa = (struct ifaddr *)in6ifa_ifpforlinklocal(cmpifp, 284 IN6_IFF_NOTREADY|IN6_IFF_ANYCAST); 285 nd6log((LOG_INFO, 286 "nd6_ns_input: nd6 proxy %s(%s)<-%s ifa %p\n", 287 if_name(cmpifp), if_name(ifp), 288 if_name(rtifp), ifa)); 289 if (ifa) { 290 proxy = 1; 291 /* 292 * Manual link address on same interface 293 * w/announce flag will proxy-arp using 294 * target mac, else our mac is used. 295 */ 296 if (cmpifp == rtifp && 297 (rt->rt_flags & RTF_ANNOUNCE) && 298 rt->rt_gateway->sa_family == AF_LINK) { 299 proxydl = SDL(rt->rt_gateway); 300 } 301 } 302 } 303 if (rt != NULL) 304 --rt->rt_refcnt; 305 } 306 if (ifa == NULL) { 307 /* 308 * We've got an NS packet, and we don't have that adddress 309 * assigned for us. We MUST silently ignore it. 310 * See RFC2461 7.2.3. 311 */ 312 goto freeit; 313 } 314 myaddr6 = *IFA_IN6(ifa); 315 anycast = ((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_ANYCAST; 316 tentative = ((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_TENTATIVE; 317 if (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_DUPLICATED) 318 goto freeit; 319 320 if (lladdr && ((cmpifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) { 321 nd6log((LOG_INFO, "nd6_ns_input: lladdrlen mismatch for %s " 322 "(if %d, NS packet %d)\n", 323 ip6_sprintf(&taddr6), cmpifp->if_addrlen, lladdrlen - 2)); 324 goto bad; 325 } 326 327 if (IN6_ARE_ADDR_EQUAL(&myaddr6, &saddr6)) { 328 nd6log((LOG_INFO, "nd6_ns_input: duplicate IP6 address %s\n", 329 ip6_sprintf(&saddr6))); 330 goto freeit; 331 } 332 333 /* 334 * We have neighbor solicitation packet, with target address equals to 335 * one of my tentative address. 336 * 337 * src addr how to process? 338 * --- --- 339 * multicast of course, invalid (rejected in ip6_input) 340 * unicast somebody is doing address resolution -> ignore 341 * unspec dup address detection 342 * 343 * The processing is defined in RFC 2462. 344 */ 345 if (tentative) { 346 /* 347 * If source address is unspecified address, it is for 348 * duplicated address detection. 349 * 350 * If not, the packet is for addess resolution; 351 * silently ignore it. 352 */ 353 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) 354 nd6_dad_ns_input(ifa); 355 356 goto freeit; 357 } 358 359 /* 360 * If the source address is unspecified address, entries must not 361 * be created or updated. 362 * It looks that sender is performing DAD. Output NA toward 363 * all-node multicast address, to tell the sender that I'm using 364 * the address. 365 * S bit ("solicited") must be zero. 366 */ 367 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) { 368 saddr6 = kin6addr_linklocal_allnodes; 369 saddr6.s6_addr16[1] = htons(cmpifp->if_index); 370 nd6_na_output(cmpifp, &saddr6, &taddr6, 371 ((anycast || proxy || !tlladdr) ? 0 : ND_NA_FLAG_OVERRIDE) | 372 (ip6_forwarding ? ND_NA_FLAG_ROUTER : 0), 373 tlladdr, (struct sockaddr *)proxydl); 374 goto freeit; 375 } 376 377 nd6_cache_lladdr(cmpifp, &saddr6, lladdr, lladdrlen, 378 ND_NEIGHBOR_SOLICIT, 0); 379 380 nd6_na_output(ifp, &saddr6, &taddr6, 381 ((anycast || proxy || !tlladdr) ? 0 : ND_NA_FLAG_OVERRIDE) | 382 (ip6_forwarding ? ND_NA_FLAG_ROUTER : 0) | ND_NA_FLAG_SOLICITED, 383 tlladdr, (struct sockaddr *)proxydl); 384 freeit: 385 m_freem(m); 386 return; 387 388 bad: 389 nd6log((LOG_ERR, "nd6_ns_input: src=%s\n", ip6_sprintf(&saddr6))); 390 nd6log((LOG_ERR, "nd6_ns_input: dst=%s\n", ip6_sprintf(&daddr6))); 391 nd6log((LOG_ERR, "nd6_ns_input: tgt=%s\n", ip6_sprintf(&taddr6))); 392 icmp6stat.icp6s_badns++; 393 m_freem(m); 394 } 395 396 /* 397 * Output an Neighbor Solicitation Message. Caller specifies: 398 * - ICMP6 header source IP6 address 399 * - ND6 header target IP6 address 400 * - ND6 header source datalink address 401 * 402 * Based on RFC 2461 403 * Based on RFC 2462 (duplicated address detection) 404 */ 405 void 406 nd6_ns_output(struct ifnet *ifp, const struct in6_addr *daddr6, 407 const struct in6_addr *taddr6, 408 struct llinfo_nd6 *ln, /* for source address determination */ 409 int dad) /* duplicated address detection */ 410 { 411 struct mbuf *m; 412 struct ip6_hdr *ip6; 413 struct nd_neighbor_solicit *nd_ns; 414 struct in6_ifaddr *ia = NULL; 415 struct ip6_moptions im6o; 416 int icmp6len; 417 int maxlen; 418 caddr_t mac; 419 struct ifnet *outif = NULL; 420 421 if (IN6_IS_ADDR_MULTICAST(taddr6)) 422 return; 423 424 /* estimate the size of message */ 425 maxlen = sizeof(*ip6) + sizeof(*nd_ns); 426 maxlen += (sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7; 427 if (max_linkhdr + maxlen > MCLBYTES) { 428 #ifdef DIAGNOSTIC 429 kprintf("nd6_ns_output: max_linkhdr + maxlen > MCLBYTES " 430 "(%d + %d > %d)\n", max_linkhdr, maxlen, MCLBYTES); 431 #endif 432 return; 433 } 434 435 m = m_getb(max_linkhdr + maxlen, M_NOWAIT, MT_DATA, M_PKTHDR); 436 if (m == NULL) 437 return; 438 439 if (daddr6 == NULL || IN6_IS_ADDR_MULTICAST(daddr6)) { 440 m->m_flags |= M_MCAST; 441 im6o.im6o_multicast_ifp = ifp; 442 im6o.im6o_multicast_hlim = 255; 443 im6o.im6o_multicast_loop = 0; 444 } 445 446 icmp6len = sizeof(*nd_ns); 447 m->m_pkthdr.len = m->m_len = sizeof(*ip6) + icmp6len; 448 m->m_data += max_linkhdr; /* or MH_ALIGN() equivalent? */ 449 450 /* fill neighbor solicitation packet */ 451 ip6 = mtod(m, struct ip6_hdr *); 452 ip6->ip6_flow = 0; 453 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 454 ip6->ip6_vfc |= IPV6_VERSION; 455 /* ip6->ip6_plen will be set later */ 456 ip6->ip6_nxt = IPPROTO_ICMPV6; 457 ip6->ip6_hlim = 255; 458 if (daddr6) 459 ip6->ip6_dst = *daddr6; 460 else { 461 ip6->ip6_dst.s6_addr16[0] = IPV6_ADDR_INT16_MLL; 462 ip6->ip6_dst.s6_addr16[1] = htons(ifp->if_index); 463 ip6->ip6_dst.s6_addr32[1] = 0; 464 ip6->ip6_dst.s6_addr32[2] = IPV6_ADDR_INT32_ONE; 465 ip6->ip6_dst.s6_addr32[3] = taddr6->s6_addr32[3]; 466 ip6->ip6_dst.s6_addr8[12] = 0xff; 467 } 468 if (!dad) { 469 /* 470 * RFC2461 7.2.2: 471 * "If the source address of the packet prompting the 472 * solicitation is the same as one of the addresses assigned 473 * to the outgoing interface, that address SHOULD be placed 474 * in the IP Source Address of the outgoing solicitation. 475 * Otherwise, any one of the addresses assigned to the 476 * interface should be used." 477 * 478 * We use the source address for the prompting packet 479 * (saddr6), if: 480 * - saddr6 is given from the caller (by giving "ln"), and 481 * - saddr6 belongs to the outgoing interface. 482 * Otherwise, we perform a scope-wise match. 483 */ 484 struct ip6_hdr *hip6; /* hold ip6 */ 485 struct in6_addr *saddr6; 486 487 if (ln && ln->ln_hold) { 488 hip6 = mtod(ln->ln_hold, struct ip6_hdr *); 489 /* XXX pullup? */ 490 if (sizeof(*hip6) < ln->ln_hold->m_len) 491 saddr6 = &hip6->ip6_src; 492 else 493 saddr6 = NULL; 494 } else 495 saddr6 = NULL; 496 if (saddr6 && in6ifa_ifpwithaddr(ifp, saddr6)) 497 bcopy(saddr6, &ip6->ip6_src, sizeof(*saddr6)); 498 else { 499 ia = in6_ifawithifp(ifp, &ip6->ip6_dst); 500 if (ia == NULL) { 501 m_freem(m); 502 return; 503 } 504 ip6->ip6_src = ia->ia_addr.sin6_addr; 505 } 506 } else { 507 /* 508 * Source address for DAD packet must always be IPv6 509 * unspecified address. (0::0) 510 */ 511 bzero(&ip6->ip6_src, sizeof(ip6->ip6_src)); 512 } 513 nd_ns = (struct nd_neighbor_solicit *)(ip6 + 1); 514 nd_ns->nd_ns_type = ND_NEIGHBOR_SOLICIT; 515 nd_ns->nd_ns_code = 0; 516 nd_ns->nd_ns_reserved = 0; 517 nd_ns->nd_ns_target = *taddr6; 518 in6_clearscope(&nd_ns->nd_ns_target); /* XXX */ 519 520 /* 521 * Add source link-layer address option. 522 * 523 * spec implementation 524 * --- --- 525 * DAD packet MUST NOT do not add the option 526 * there's no link layer address: 527 * impossible do not add the option 528 * there's link layer address: 529 * Multicast NS MUST add one add the option 530 * Unicast NS SHOULD add one add the option 531 */ 532 if (!dad && (mac = nd6_ifptomac(ifp))) { 533 int optlen = sizeof(struct nd_opt_hdr) + ifp->if_addrlen; 534 struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)(nd_ns + 1); 535 /* 8 byte alignments... */ 536 optlen = (optlen + 7) & ~7; 537 538 m->m_pkthdr.len += optlen; 539 m->m_len += optlen; 540 icmp6len += optlen; 541 bzero((caddr_t)nd_opt, optlen); 542 nd_opt->nd_opt_type = ND_OPT_SOURCE_LINKADDR; 543 nd_opt->nd_opt_len = optlen >> 3; 544 bcopy(mac, (caddr_t)(nd_opt + 1), ifp->if_addrlen); 545 } 546 547 ip6->ip6_plen = htons((u_short)icmp6len); 548 nd_ns->nd_ns_cksum = 0; 549 nd_ns->nd_ns_cksum = 550 in6_cksum(m, IPPROTO_ICMPV6, sizeof(*ip6), icmp6len); 551 552 ip6_output(m, NULL, NULL, dad ? IPV6_DADOUTPUT : 0, &im6o, &outif, NULL); 553 if (outif) { 554 icmp6_ifstat_inc(outif, ifs6_out_msg); 555 icmp6_ifstat_inc(outif, ifs6_out_neighborsolicit); 556 } 557 icmp6stat.icp6s_outhist[ND_NEIGHBOR_SOLICIT]++; 558 } 559 560 /* 561 * Neighbor advertisement input handling. 562 * 563 * Based on RFC 2461 564 * Based on RFC 2462 (duplicated address detection) 565 * 566 * the following items are not implemented yet: 567 * - proxy advertisement delay rule (RFC2461 7.2.8, last paragraph, SHOULD) 568 * - anycast advertisement delay rule (RFC2461 7.2.7, SHOULD) 569 */ 570 void 571 nd6_na_input(struct mbuf *m, int off, int icmp6len) 572 { 573 struct ifnet *ifp = m->m_pkthdr.rcvif; 574 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 575 struct nd_neighbor_advert *nd_na; 576 struct in6_addr saddr6 = ip6->ip6_src; 577 struct in6_addr daddr6 = ip6->ip6_dst; 578 struct in6_addr taddr6; 579 int flags; 580 int is_router; 581 int is_solicited; 582 int is_override; 583 char *lladdr = NULL; 584 int lladdrlen = 0; 585 struct ifaddr *ifa; 586 struct llinfo_nd6 *ln; 587 struct rtentry *rt; 588 struct sockaddr_dl *sdl; 589 union nd_opts ndopts; 590 591 if (ip6->ip6_hlim != 255) { 592 nd6log((LOG_ERR, 593 "nd6_na_input: invalid hlim (%d) from %s to %s on %s\n", 594 ip6->ip6_hlim, ip6_sprintf(&ip6->ip6_src), 595 ip6_sprintf(&ip6->ip6_dst), if_name(ifp))); 596 goto bad; 597 } 598 599 #ifndef PULLDOWN_TEST 600 IP6_EXTHDR_CHECK(m, off, icmp6len,); 601 nd_na = (struct nd_neighbor_advert *)((caddr_t)ip6 + off); 602 #else 603 IP6_EXTHDR_GET(nd_na, struct nd_neighbor_advert *, m, off, icmp6len); 604 if (nd_na == NULL) { 605 icmp6stat.icp6s_tooshort++; 606 return; 607 } 608 #endif 609 taddr6 = nd_na->nd_na_target; 610 flags = nd_na->nd_na_flags_reserved; 611 is_router = ((flags & ND_NA_FLAG_ROUTER) != 0); 612 is_solicited = ((flags & ND_NA_FLAG_SOLICITED) != 0); 613 is_override = ((flags & ND_NA_FLAG_OVERRIDE) != 0); 614 615 if (IN6_IS_SCOPE_LINKLOCAL(&taddr6)) 616 taddr6.s6_addr16[1] = htons(ifp->if_index); 617 618 if (IN6_IS_ADDR_MULTICAST(&taddr6)) { 619 nd6log((LOG_ERR, 620 "nd6_na_input: invalid target address %s\n", 621 ip6_sprintf(&taddr6))); 622 goto bad; 623 } 624 if (IN6_IS_ADDR_MULTICAST(&daddr6)) 625 if (is_solicited) { 626 nd6log((LOG_ERR, 627 "nd6_na_input: a solicited adv is multicasted\n")); 628 goto bad; 629 } 630 631 icmp6len -= sizeof(*nd_na); 632 nd6_option_init(nd_na + 1, icmp6len, &ndopts); 633 if (nd6_options(&ndopts) < 0) { 634 nd6log((LOG_INFO, 635 "nd6_na_input: invalid ND option, ignored\n")); 636 /* nd6_options have incremented stats */ 637 goto freeit; 638 } 639 640 if (ndopts.nd_opts_tgt_lladdr) { 641 struct ifnet *ifp_ll; 642 643 lladdr = (char *)(ndopts.nd_opts_tgt_lladdr + 1); 644 lladdrlen = ndopts.nd_opts_tgt_lladdr->nd_opt_len << 3; 645 646 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) { 647 nd6log((LOG_INFO, "nd6_na_input: lladdrlen mismatch " 648 "for %s (if %d, NA packet %d)\n", ip6_sprintf(&taddr6), 649 ifp->if_addrlen, lladdrlen - 2)); 650 goto bad; 651 } 652 653 /* If it's from me, ignore it. */ 654 ifp_ll = if_bylla(lladdr, ifp->if_addrlen); 655 if (ifp_ll != NULL) 656 goto freeit; 657 } 658 659 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &taddr6); 660 661 /* 662 * Target address matches one of my interface address. 663 * 664 * If my address is tentative, this means that there's somebody 665 * already using the same address as mine. This indicates DAD failure. 666 * This is defined in RFC 2462. 667 * 668 * Otherwise, process as defined in RFC 2461. 669 */ 670 if (ifa 671 && (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_TENTATIVE)) { 672 nd6_dad_na_input(ifa); 673 goto freeit; 674 } 675 676 /* Just for safety, maybe unnecessary. */ 677 if (ifa) { 678 log(LOG_ERR, 679 "nd6_na_input: duplicate IP6 address %s\n", 680 ip6_sprintf(&taddr6)); 681 goto freeit; 682 } 683 684 if (!nd6_onlink_ns_rfc4861) { 685 /* 686 * Make sure the source address is from a neighbor's address. 687 */ 688 if (in6ifa_ifplocaladdr(ifp, &saddr6) == NULL) { 689 nd6log((LOG_INFO, "nd6_na_input: " 690 "NA packet from non-neighbor\n")); 691 goto bad; 692 } 693 } 694 695 /* 696 * If no neighbor cache entry is found, NA SHOULD silently be discarded. 697 */ 698 rt = nd6_lookup(&taddr6, 0, ifp); 699 if ((rt == NULL) || 700 ((ln = (struct llinfo_nd6 *)rt->rt_llinfo) == NULL) || 701 ((sdl = SDL(rt->rt_gateway)) == NULL)) 702 goto freeit; 703 704 if (ln->ln_state <= ND6_LLINFO_INCOMPLETE) { 705 /* 706 * If the link-layer has address, and no lladdr option came, 707 * discard the packet. 708 */ 709 if (ifp->if_addrlen && !lladdr) 710 goto freeit; 711 712 /* 713 * Record link-layer address, and update the state. 714 */ 715 sdl->sdl_alen = ifp->if_addrlen; 716 bcopy(lladdr, LLADDR(sdl), ifp->if_addrlen); 717 if (is_solicited) { 718 ln->ln_state = ND6_LLINFO_REACHABLE; 719 ln->ln_byhint = 0; 720 if (ln->ln_expire) { 721 ln->ln_expire = time_uptime + 722 ND_IFINFO(rt->rt_ifp)->reachable; 723 } 724 } else { 725 ln->ln_state = ND6_LLINFO_STALE; 726 ln->ln_expire = time_uptime + nd6_gctimer; 727 } 728 if ((ln->ln_router = is_router) != 0) { 729 /* 730 * This means a router's state has changed from 731 * non-reachable to probably reachable, and might 732 * affect the status of associated prefixes.. 733 */ 734 pfxlist_onlink_check(); 735 } 736 } else { 737 int llchange; 738 739 /* 740 * Check if the link-layer address has changed or not. 741 */ 742 if (!lladdr) 743 llchange = 0; 744 else { 745 if (sdl->sdl_alen) { 746 if (bcmp(lladdr, LLADDR(sdl), ifp->if_addrlen)) 747 llchange = 1; 748 else 749 llchange = 0; 750 } else 751 llchange = 1; 752 } 753 754 /* 755 * This is VERY complex. Look at it with care. 756 * 757 * override solicit lladdr llchange action 758 * (L: record lladdr) 759 * 760 * 0 0 n -- (2c) 761 * 0 0 y n (2b) L 762 * 0 0 y y (1) REACHABLE->STALE 763 * 0 1 n -- (2c) *->REACHABLE 764 * 0 1 y n (2b) L *->REACHABLE 765 * 0 1 y y (1) REACHABLE->STALE 766 * 1 0 n -- (2a) 767 * 1 0 y n (2a) L 768 * 1 0 y y (2a) L *->STALE 769 * 1 1 n -- (2a) *->REACHABLE 770 * 1 1 y n (2a) L *->REACHABLE 771 * 1 1 y y (2a) L *->REACHABLE 772 */ 773 if (!is_override && (lladdr && llchange)) { /* (1) */ 774 /* 775 * If state is REACHABLE, make it STALE. 776 * no other updates should be done. 777 */ 778 if (ln->ln_state == ND6_LLINFO_REACHABLE) { 779 ln->ln_state = ND6_LLINFO_STALE; 780 ln->ln_expire = time_uptime + nd6_gctimer; 781 } 782 goto freeit; 783 } else if (is_override /* (2a) */ 784 || (lladdr && !llchange) /* (2b) */ 785 || !lladdr) { /* (2c) */ 786 /* 787 * Update link-local address, if any. 788 */ 789 if (lladdr) { 790 sdl->sdl_alen = ifp->if_addrlen; 791 bcopy(lladdr, LLADDR(sdl), ifp->if_addrlen); 792 } 793 794 /* 795 * If solicited, make the state REACHABLE. 796 * If not solicited and the link-layer address was 797 * changed, make it STALE. 798 */ 799 if (is_solicited) { 800 ln->ln_state = ND6_LLINFO_REACHABLE; 801 ln->ln_byhint = 0; 802 if (ln->ln_expire) { 803 ln->ln_expire = time_uptime + 804 ND_IFINFO(ifp)->reachable; 805 } 806 } else { 807 if (lladdr && llchange) { 808 ln->ln_state = ND6_LLINFO_STALE; 809 ln->ln_expire = time_uptime + nd6_gctimer; 810 } 811 } 812 } 813 814 if (ln->ln_router && !is_router) { 815 /* 816 * The peer dropped the router flag. 817 * Remove the sender from the Default Router List and 818 * update the Destination Cache entries. 819 */ 820 struct nd_defrouter *dr; 821 struct in6_addr *in6; 822 823 in6 = &((struct sockaddr_in6 *)rt_key(rt))->sin6_addr; 824 825 /* 826 * Lock to protect the default router list. 827 * XXX: this might be unnecessary, since this function 828 * is only called under the network software interrupt 829 * context. However, we keep it just for safety. 830 */ 831 mtx_lock(&nd6_mtx); 832 dr = defrouter_lookup(in6, rt->rt_ifp); 833 if (dr) 834 defrtrlist_del(dr); 835 mtx_unlock(&nd6_mtx); 836 837 if (dr == NULL && !ip6_forwarding && ip6_accept_rtadv) { 838 /* 839 * Even if the neighbor is not in the default 840 * router list, the neighbor may be used 841 * as a next hop for some destinations 842 * (e.g. redirect case). So we must 843 * call rt6_flush explicitly. 844 */ 845 rt6_flush(&ip6->ip6_src, rt->rt_ifp); 846 } 847 } 848 ln->ln_router = is_router; 849 } 850 rt->rt_flags &= ~RTF_REJECT; 851 ln->ln_asked = 0; 852 if (ln->ln_hold) { 853 /* 854 * we assume ifp is not a loopback here, so just set the 2nd 855 * argument as the 1st one. 856 */ 857 nd6_output(ifp, ifp, ln->ln_hold, 858 (struct sockaddr_in6 *)rt_key(rt), rt); 859 ln->ln_hold = NULL; 860 } 861 862 freeit: 863 m_freem(m); 864 return; 865 866 bad: 867 icmp6stat.icp6s_badna++; 868 m_freem(m); 869 } 870 871 /* 872 * Neighbor advertisement output handling. 873 * 874 * Based on RFC 2461 875 * 876 * the following items are not implemented yet: 877 * - proxy advertisement delay rule (RFC2461 7.2.8, last paragraph, SHOULD) 878 * - anycast advertisement delay rule (RFC2461 7.2.7, SHOULD) 879 */ 880 void 881 nd6_na_output(struct ifnet *ifp, const struct in6_addr *daddr6, 882 const struct in6_addr *taddr6, u_long flags, 883 int tlladdr, /* 1 if include target link-layer address */ 884 struct sockaddr *sdl0) /* sockaddr_dl (= proxy NA) or NULL */ 885 { 886 struct mbuf *m; 887 struct ip6_hdr *ip6; 888 struct nd_neighbor_advert *nd_na; 889 struct in6_ifaddr *ia = NULL; 890 struct ip6_moptions im6o; 891 int icmp6len; 892 int maxlen; 893 caddr_t mac; 894 struct ifnet *outif = NULL; 895 896 /* estimate the size of message */ 897 maxlen = sizeof(*ip6) + sizeof(*nd_na); 898 maxlen += (sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7; 899 if (max_linkhdr + maxlen > MCLBYTES) { 900 #ifdef DIAGNOSTIC 901 kprintf("nd6_na_output: max_linkhdr + maxlen > MCLBYTES " 902 "(%d + %d > %d)\n", max_linkhdr, maxlen, MCLBYTES); 903 #endif 904 return; 905 } 906 907 m = m_getb(max_linkhdr + maxlen, M_NOWAIT, MT_DATA, M_PKTHDR); 908 if (m == NULL) 909 return; 910 911 if (IN6_IS_ADDR_MULTICAST(daddr6)) { 912 m->m_flags |= M_MCAST; 913 im6o.im6o_multicast_ifp = ifp; 914 im6o.im6o_multicast_hlim = 255; 915 im6o.im6o_multicast_loop = 0; 916 } 917 918 icmp6len = sizeof(*nd_na); 919 m->m_pkthdr.len = m->m_len = sizeof(struct ip6_hdr) + icmp6len; 920 m->m_data += max_linkhdr; /* or MH_ALIGN() equivalent? */ 921 922 /* fill neighbor advertisement packet */ 923 ip6 = mtod(m, struct ip6_hdr *); 924 ip6->ip6_flow = 0; 925 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 926 ip6->ip6_vfc |= IPV6_VERSION; 927 ip6->ip6_nxt = IPPROTO_ICMPV6; 928 ip6->ip6_hlim = 255; 929 if (IN6_IS_ADDR_UNSPECIFIED(daddr6)) { 930 /* reply to DAD */ 931 ip6->ip6_dst.s6_addr16[0] = IPV6_ADDR_INT16_MLL; 932 ip6->ip6_dst.s6_addr16[1] = htons(ifp->if_index); 933 ip6->ip6_dst.s6_addr32[1] = 0; 934 ip6->ip6_dst.s6_addr32[2] = 0; 935 ip6->ip6_dst.s6_addr32[3] = IPV6_ADDR_INT32_ONE; 936 flags &= ~ND_NA_FLAG_SOLICITED; 937 } else 938 ip6->ip6_dst = *daddr6; 939 940 /* 941 * Select a source whose scope is the same as that of the dest. 942 */ 943 ia = in6_ifawithifp(ifp, &ip6->ip6_dst); 944 if (ia == NULL) { 945 m_freem(m); 946 return; 947 } 948 ip6->ip6_src = ia->ia_addr.sin6_addr; 949 nd_na = (struct nd_neighbor_advert *)(ip6 + 1); 950 nd_na->nd_na_type = ND_NEIGHBOR_ADVERT; 951 nd_na->nd_na_code = 0; 952 nd_na->nd_na_target = *taddr6; 953 in6_clearscope(&nd_na->nd_na_target); /* XXX */ 954 955 /* 956 * "tlladdr" indicates NS's condition for adding tlladdr or not. 957 * see nd6_ns_input() for details. 958 * Basically, if NS packet is sent to unicast/anycast addr, 959 * target lladdr option SHOULD NOT be included. 960 */ 961 mac = NULL; 962 if (tlladdr) { 963 /* 964 * sdl0 != NULL indicates proxy NA. If we do proxy, use 965 * lladdr in sdl0. If we are not proxying (sending NA for 966 * my address) use lladdr configured for the interface. 967 */ 968 if (sdl0 == NULL) { 969 #ifdef CARP 970 if (ifp->if_carp) 971 mac = carp_macmatch6(ifp->if_carp, m, taddr6); 972 if (mac == NULL) 973 mac = nd6_ifptomac(ifp); 974 #else 975 mac = nd6_ifptomac(ifp); 976 #endif 977 } else if (sdl0->sa_family == AF_LINK) { 978 struct sockaddr_dl *sdl; 979 sdl = (struct sockaddr_dl *)sdl0; 980 if (sdl->sdl_alen == ifp->if_addrlen) 981 mac = LLADDR(sdl); 982 } 983 } 984 if (mac != NULL) { 985 int optlen = sizeof(struct nd_opt_hdr) + ifp->if_addrlen; 986 struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)(nd_na + 1); 987 988 /* roundup to 8 bytes alignment! */ 989 optlen = (optlen + 7) & ~7; 990 991 m->m_pkthdr.len += optlen; 992 m->m_len += optlen; 993 icmp6len += optlen; 994 bzero((caddr_t)nd_opt, optlen); 995 nd_opt->nd_opt_type = ND_OPT_TARGET_LINKADDR; 996 nd_opt->nd_opt_len = optlen >> 3; 997 bcopy(mac, (caddr_t)(nd_opt + 1), ifp->if_addrlen); 998 } else 999 flags &= ~ND_NA_FLAG_OVERRIDE; 1000 1001 ip6->ip6_plen = htons((u_short)icmp6len); 1002 nd_na->nd_na_flags_reserved = flags; 1003 nd_na->nd_na_cksum = 0; 1004 nd_na->nd_na_cksum = 1005 in6_cksum(m, IPPROTO_ICMPV6, sizeof(struct ip6_hdr), icmp6len); 1006 1007 ip6_output(m, NULL, NULL, 0, &im6o, &outif, NULL); 1008 if (outif) { 1009 icmp6_ifstat_inc(outif, ifs6_out_msg); 1010 icmp6_ifstat_inc(outif, ifs6_out_neighboradvert); 1011 } 1012 icmp6stat.icp6s_outhist[ND_NEIGHBOR_ADVERT]++; 1013 } 1014 1015 caddr_t 1016 nd6_ifptomac(struct ifnet *ifp) 1017 { 1018 switch (ifp->if_type) { 1019 case IFT_ETHER: 1020 case IFT_IEEE1394: 1021 #ifdef IFT_L2VLAN 1022 case IFT_L2VLAN: 1023 #endif 1024 #ifdef IFT_IEEE80211 1025 case IFT_IEEE80211: 1026 #endif 1027 #ifdef IFT_CARP 1028 case IFT_CARP: 1029 #endif 1030 return ((caddr_t)(ifp + 1)); 1031 default: 1032 return NULL; 1033 } 1034 } 1035 1036 struct netmsg_dad { 1037 struct netmsg_base base; 1038 struct dadq *dadq; 1039 }; 1040 1041 struct dadq { 1042 TAILQ_ENTRY(dadq) dad_list; 1043 struct ifaddr *dad_ifa; 1044 int dad_count; /* max NS to send */ 1045 int dad_ns_tcount; /* # of trials to send NS */ 1046 int dad_ns_ocount; /* NS sent so far */ 1047 int dad_ns_icount; 1048 int dad_na_icount; 1049 struct callout dad_timer_ch; 1050 struct netmsg_dad dad_nmsg; 1051 }; 1052 TAILQ_HEAD(dadq_head, dadq); 1053 1054 static struct dadq_head dadq = TAILQ_HEAD_INITIALIZER(dadq); 1055 1056 static struct dadq * 1057 nd6_dad_find(struct ifaddr *ifa) 1058 { 1059 struct dadq *dp; 1060 1061 ASSERT_NETISR0; 1062 1063 TAILQ_FOREACH(dp, &dadq, dad_list) { 1064 if (dp->dad_ifa == ifa) 1065 return dp; 1066 } 1067 return NULL; 1068 } 1069 1070 static void 1071 nd6_dad_starttimer(struct dadq *dp, int ticks) 1072 { 1073 ASSERT_NETISR0; 1074 callout_reset(&dp->dad_timer_ch, ticks, nd6_dad_timer, dp); 1075 } 1076 1077 static void 1078 nd6_dad_stoptimer(struct dadq *dp) 1079 { 1080 ASSERT_NETISR0; 1081 callout_stop(&dp->dad_timer_ch); 1082 } 1083 1084 /* 1085 * Start Duplicated Address Detection (DAD) for specified interface address. 1086 */ 1087 void 1088 nd6_dad_start(struct ifaddr *ifa, 1089 int *tick) /* minimum delay ticks for IFF_UP event */ 1090 { 1091 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1092 struct dadq *dp; 1093 1094 ASSERT_NETISR0; 1095 1096 /* 1097 * If we don't need DAD, don't do it. 1098 * There are several cases: 1099 * - DAD is disabled (ip6_dad_count == 0) 1100 * - the interface address is anycast 1101 */ 1102 if (!(ia->ia6_flags & IN6_IFF_TENTATIVE)) { 1103 log(LOG_DEBUG, 1104 "nd6_dad_start: called with non-tentative address " 1105 "%s(%s)\n", 1106 ip6_sprintf(&ia->ia_addr.sin6_addr), 1107 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1108 return; 1109 } 1110 if (ia->ia6_flags & IN6_IFF_ANYCAST || !ip6_dad_count) { 1111 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1112 in6_newaddrmsg(ifa); 1113 return; 1114 } 1115 if (!ifa->ifa_ifp) 1116 panic("nd6_dad_start: ifa->ifa_ifp == NULL"); 1117 if (!(ifa->ifa_ifp->if_flags & IFF_UP)) 1118 return; 1119 if (nd6_dad_find(ifa) != NULL) { 1120 /* DAD already in progress */ 1121 return; 1122 } 1123 1124 dp = nd6_dad_create(ifa); 1125 nd6log((LOG_DEBUG, "%s: starting DAD for %s\n", if_name(ifa->ifa_ifp), 1126 ip6_sprintf(&ia->ia_addr.sin6_addr))); 1127 1128 /* 1129 * Send NS packet for DAD, dp->dad_count times. 1130 * Note that we must delay the first transmission, if this is the 1131 * first packet to be sent from the interface after interface 1132 * (re)initialization. 1133 */ 1134 if (tick == NULL) { 1135 nd6_dad_ns_output(dp); 1136 nd6_dad_starttimer(dp, 1137 ND_IFINFO(ifa->ifa_ifp)->retrans * hz / 1000); 1138 } else { 1139 int ntick; 1140 1141 if (*tick == 0) 1142 ntick = krandom() % (MAX_RTR_SOLICITATION_DELAY * hz); 1143 else 1144 ntick = *tick + krandom() % (hz / 2); 1145 *tick = ntick; 1146 nd6_dad_starttimer(dp, ntick); 1147 } 1148 } 1149 1150 /* 1151 * Terminate DAD unconditionally. Used for address removals. 1152 */ 1153 void 1154 nd6_dad_stop(struct ifaddr *ifa) 1155 { 1156 struct dadq *dp; 1157 1158 ASSERT_NETISR0; 1159 1160 dp = nd6_dad_find(ifa); 1161 if (!dp) { 1162 /* DAD wasn't started yet */ 1163 return; 1164 } 1165 nd6_dad_destroy(dp); 1166 } 1167 1168 static struct dadq * 1169 nd6_dad_create(struct ifaddr *ifa) 1170 { 1171 struct netmsg_dad *dm; 1172 struct dadq *dp; 1173 1174 ASSERT_NETISR0; 1175 1176 dp = kmalloc(sizeof(*dp), M_IP6NDP, M_INTWAIT | M_ZERO); 1177 callout_init_mp(&dp->dad_timer_ch); 1178 1179 dm = &dp->dad_nmsg; 1180 netmsg_init(&dm->base, NULL, &netisr_adone_rport, 1181 MSGF_DROPABLE | MSGF_PRIORITY, nd6_dad_timer_handler); 1182 dm->dadq = dp; 1183 1184 dp->dad_ifa = ifa; 1185 IFAREF(ifa); /* just for safety */ 1186 1187 /* Send NS packet for DAD, ip6_dad_count times. */ 1188 dp->dad_count = ip6_dad_count; 1189 1190 TAILQ_INSERT_TAIL(&dadq, dp, dad_list); 1191 1192 return dp; 1193 } 1194 1195 static void 1196 nd6_dad_destroy(struct dadq *dp) 1197 { 1198 struct lwkt_msg *lmsg = &dp->dad_nmsg.base.lmsg; 1199 1200 ASSERT_NETISR0; 1201 1202 TAILQ_REMOVE(&dadq, dp, dad_list); 1203 1204 nd6_dad_stoptimer(dp); 1205 1206 crit_enter(); 1207 if ((lmsg->ms_flags & MSGF_DONE) == 0) 1208 lwkt_dropmsg(lmsg); 1209 crit_exit(); 1210 1211 IFAFREE(dp->dad_ifa); 1212 kfree(dp, M_IP6NDP); 1213 } 1214 1215 static void 1216 nd6_dad_timer(void *xdp) 1217 { 1218 struct dadq *dp = xdp; 1219 struct lwkt_msg *lmsg = &dp->dad_nmsg.base.lmsg; 1220 1221 KASSERT(mycpuid == 0, ("dad timer not on cpu0")); 1222 1223 crit_enter(); 1224 if (lmsg->ms_flags & MSGF_DONE) 1225 lwkt_sendmsg_oncpu(netisr_cpuport(0), lmsg); 1226 crit_exit(); 1227 } 1228 1229 static void 1230 nd6_dad_timer_handler(netmsg_t msg) 1231 { 1232 struct netmsg_dad *dm = (struct netmsg_dad *)msg; 1233 struct dadq *dp = dm->dadq; 1234 struct ifaddr *ifa = dp->dad_ifa; 1235 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1236 1237 ASSERT_NETISR0; 1238 1239 /* Reply ASAP */ 1240 crit_enter(); 1241 lwkt_replymsg(&dm->base.lmsg, 0); 1242 crit_exit(); 1243 1244 if (ia->ia6_flags & IN6_IFF_DUPLICATED) { 1245 log(LOG_ERR, "nd6_dad_timer: called with duplicated address " 1246 "%s(%s)\n", 1247 ip6_sprintf(&ia->ia_addr.sin6_addr), 1248 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1249 goto destroy; 1250 } 1251 if (!(ia->ia6_flags & IN6_IFF_TENTATIVE)) { 1252 log(LOG_ERR, "nd6_dad_timer: called with non-tentative address " 1253 "%s(%s)\n", 1254 ip6_sprintf(&ia->ia_addr.sin6_addr), 1255 ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); 1256 goto destroy; 1257 } 1258 1259 /* Timed out with IFF_{RUNNING,UP} check */ 1260 if (dp->dad_ns_tcount > dad_maxtry) { 1261 nd6log((LOG_INFO, "%s: could not run DAD, driver problem?\n", 1262 if_name(ifa->ifa_ifp))); 1263 goto destroy; 1264 } 1265 1266 /* Need more checks? */ 1267 if (dp->dad_ns_ocount < dp->dad_count) { 1268 /* 1269 * We have more NS to go. Send NS packet for DAD. 1270 */ 1271 nd6_dad_ns_output(dp); 1272 nd6_dad_starttimer(dp, 1273 ND_IFINFO(ifa->ifa_ifp)->retrans * hz / 1000); 1274 } else { 1275 /* 1276 * We have transmitted sufficient number of DAD packets. 1277 * See what we've got. 1278 */ 1279 int duplicate; 1280 1281 duplicate = 0; 1282 1283 if (dp->dad_na_icount) { 1284 /* 1285 * the check is in nd6_dad_na_input(), 1286 * but just in case 1287 */ 1288 duplicate++; 1289 } 1290 1291 if (dp->dad_ns_icount) { 1292 #if 0 /* heuristics */ 1293 /* 1294 * if 1295 * - we have sent many(?) DAD NS, and 1296 * - the number of NS we sent equals to the 1297 * number of NS we've got, and 1298 * - we've got no NA 1299 * we may have a faulty network card/driver which 1300 * loops back multicasts to myself. 1301 */ 1302 if (3 < dp->dad_count 1303 && dp->dad_ns_icount == dp->dad_count 1304 && dp->dad_na_icount == 0) { 1305 log(LOG_INFO, "DAD questionable for %s(%s): " 1306 "network card loops back multicast?\n", 1307 ip6_sprintf(&ia->ia_addr.sin6_addr), 1308 if_name(ifa->ifa_ifp)); 1309 /* XXX consider it a duplicate or not? */ 1310 /* duplicate++; */ 1311 } else { 1312 /* We've seen NS, means DAD has failed. */ 1313 duplicate++; 1314 } 1315 #else 1316 /* We've seen NS, means DAD has failed. */ 1317 duplicate++; 1318 #endif 1319 } 1320 1321 if (duplicate) { 1322 /* dp will be freed in nd6_dad_duplicated() */ 1323 dp = NULL; 1324 nd6_dad_duplicated(ifa); 1325 } else { 1326 /* 1327 * We are done with DAD. No NA came, no NS came. 1328 * duplicated address found. 1329 */ 1330 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1331 in6_newaddrmsg(ifa); 1332 nd6log((LOG_DEBUG, 1333 "%s: DAD complete for %s - no duplicates found\n", 1334 if_name(ifa->ifa_ifp), 1335 ip6_sprintf(&ia->ia_addr.sin6_addr))); 1336 goto destroy; 1337 } 1338 } 1339 return; 1340 destroy: 1341 nd6_dad_destroy(dp); 1342 } 1343 1344 static void 1345 nd6_dad_duplicated(struct ifaddr *ifa) 1346 { 1347 struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; 1348 struct dadq *dp; 1349 1350 ASSERT_NETISR0; 1351 1352 dp = nd6_dad_find(ifa); 1353 if (dp == NULL) { 1354 log(LOG_ERR, "nd6_dad_duplicated: DAD structure not found\n"); 1355 return; 1356 } 1357 1358 /* 1359 * We are done with DAD, with duplicated address found. (failure) 1360 */ 1361 log(LOG_ERR, "%s: DAD detected duplicate IPv6 address %s: " 1362 "NS in/out=%d/%d, NA in=%d\n", 1363 if_name(ifa->ifa_ifp), ip6_sprintf(&ia->ia_addr.sin6_addr), 1364 dp->dad_ns_icount, dp->dad_ns_ocount, dp->dad_na_icount); 1365 1366 ia->ia6_flags &= ~IN6_IFF_TENTATIVE; 1367 ia->ia6_flags |= IN6_IFF_DUPLICATED; 1368 in6_newaddrmsg(ifa); 1369 1370 log(LOG_ERR, "%s: DAD complete for %s - duplicate found\n", 1371 if_name(ifa->ifa_ifp), ip6_sprintf(&ia->ia_addr.sin6_addr)); 1372 log(LOG_ERR, "%s: manual intervention required\n", 1373 if_name(ifa->ifa_ifp)); 1374 1375 nd6_dad_destroy(dp); 1376 } 1377 1378 static void 1379 nd6_dad_ns_output(struct dadq *dp) 1380 { 1381 struct in6_ifaddr *ia = (struct in6_ifaddr *)dp->dad_ifa; 1382 struct ifnet *ifp = dp->dad_ifa->ifa_ifp; 1383 1384 ASSERT_NETISR0; 1385 1386 dp->dad_ns_tcount++; 1387 if (!(ifp->if_flags & IFF_UP)) { 1388 #if 0 1389 kprintf("%s: interface down?\n", if_name(ifp)); 1390 #endif 1391 return; 1392 } 1393 if (!(ifp->if_flags & IFF_RUNNING)) { 1394 #if 0 1395 kprintf("%s: interface not running?\n", if_name(ifp)); 1396 #endif 1397 return; 1398 } 1399 1400 dp->dad_ns_ocount++; 1401 nd6_ns_output(ifp, NULL, &ia->ia_addr.sin6_addr, NULL, 1); 1402 } 1403 1404 static void 1405 nd6_dad_ns_input(struct ifaddr *ifa) 1406 { 1407 struct in6_ifaddr *ia; 1408 const struct in6_addr *taddr6; 1409 struct dadq *dp; 1410 int duplicate; 1411 1412 ASSERT_NETISR0; 1413 1414 if (!ifa) 1415 panic("ifa == NULL in nd6_dad_ns_input"); 1416 1417 ia = (struct in6_ifaddr *)ifa; 1418 taddr6 = &ia->ia_addr.sin6_addr; 1419 duplicate = 0; 1420 dp = nd6_dad_find(ifa); 1421 1422 /* Quickhack - completely ignore DAD NS packets */ 1423 if (dad_ignore_ns) { 1424 nd6log((LOG_INFO, 1425 "nd6_dad_ns_input: ignoring DAD NS packet for " 1426 "address %s(%s)\n", ip6_sprintf(taddr6), 1427 if_name(ifa->ifa_ifp))); 1428 return; 1429 } 1430 1431 /* 1432 * if I'm yet to start DAD, someone else started using this address 1433 * first. I have a duplicate and you win. 1434 */ 1435 if (!dp || dp->dad_ns_ocount == 0) 1436 duplicate++; 1437 1438 /* XXX more checks for loopback situation - see nd6_dad_timer too */ 1439 1440 if (duplicate) { 1441 dp = NULL; /* will be freed in nd6_dad_duplicated() */ 1442 nd6_dad_duplicated(ifa); 1443 } else { 1444 /* 1445 * not sure if I got a duplicate. 1446 * increment ns count and see what happens. 1447 */ 1448 if (dp) 1449 dp->dad_ns_icount++; 1450 } 1451 } 1452 1453 static void 1454 nd6_dad_na_input(struct ifaddr *ifa) 1455 { 1456 struct dadq *dp; 1457 1458 ASSERT_NETISR0; 1459 1460 if (!ifa) 1461 panic("ifa == NULL in nd6_dad_na_input"); 1462 1463 dp = nd6_dad_find(ifa); 1464 if (dp) 1465 dp->dad_na_icount++; 1466 1467 /* remove the address. */ 1468 nd6_dad_duplicated(ifa); 1469 } 1470