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_rtr.c,v 1.111 2001/04/27 01:37:15 jinmei Exp $ 30 */ 31 32 #include <sys/cdefs.h> 33 __FBSDID("$FreeBSD$"); 34 35 #include "opt_inet.h" 36 #include "opt_inet6.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/refcount.h> 43 #include <sys/socket.h> 44 #include <sys/sockio.h> 45 #include <sys/time.h> 46 #include <sys/kernel.h> 47 #include <sys/lock.h> 48 #include <sys/errno.h> 49 #include <sys/rwlock.h> 50 #include <sys/syslog.h> 51 #include <sys/queue.h> 52 53 #include <net/if.h> 54 #include <net/if_var.h> 55 #include <net/if_types.h> 56 #include <net/if_dl.h> 57 #include <net/route.h> 58 #include <net/route_var.h> 59 #include <net/radix.h> 60 #include <net/vnet.h> 61 62 #include <netinet/in.h> 63 #include <net/if_llatbl.h> 64 #include <netinet6/in6_var.h> 65 #include <netinet6/in6_ifattach.h> 66 #include <netinet/ip6.h> 67 #include <netinet6/ip6_var.h> 68 #include <netinet6/nd6.h> 69 #include <netinet/icmp6.h> 70 #include <netinet6/scope6_var.h> 71 72 static int rtpref(struct nd_defrouter *); 73 static struct nd_defrouter *defrtrlist_update(struct nd_defrouter *); 74 static int prelist_update(struct nd_prefixctl *, struct nd_defrouter *, 75 struct mbuf *, int); 76 static struct in6_ifaddr *in6_ifadd(struct nd_prefixctl *, int); 77 static struct nd_pfxrouter *pfxrtr_lookup(struct nd_prefix *, 78 struct nd_defrouter *); 79 static void pfxrtr_add(struct nd_prefix *, struct nd_defrouter *); 80 static void pfxrtr_del(struct nd_pfxrouter *); 81 static struct nd_pfxrouter *find_pfxlist_reachable_router 82 (struct nd_prefix *); 83 static void defrouter_delreq(struct nd_defrouter *); 84 static void nd6_rtmsg(int, struct rtentry *); 85 86 static int in6_init_prefix_ltimes(struct nd_prefix *); 87 static void in6_init_address_ltimes(struct nd_prefix *, 88 struct in6_addrlifetime *); 89 90 static int nd6_prefix_onlink(struct nd_prefix *); 91 static int nd6_prefix_offlink(struct nd_prefix *); 92 93 static int rt6_deleteroute(const struct rtentry *, void *); 94 95 VNET_DECLARE(int, nd6_recalc_reachtm_interval); 96 #define V_nd6_recalc_reachtm_interval VNET(nd6_recalc_reachtm_interval) 97 98 static VNET_DEFINE(struct ifnet *, nd6_defifp); 99 VNET_DEFINE(int, nd6_defifindex); 100 #define V_nd6_defifp VNET(nd6_defifp) 101 102 VNET_DEFINE(int, ip6_use_tempaddr) = 0; 103 104 VNET_DEFINE(int, ip6_desync_factor); 105 VNET_DEFINE(u_int32_t, ip6_temp_preferred_lifetime) = DEF_TEMP_PREFERRED_LIFETIME; 106 VNET_DEFINE(u_int32_t, ip6_temp_valid_lifetime) = DEF_TEMP_VALID_LIFETIME; 107 108 VNET_DEFINE(int, ip6_temp_regen_advance) = TEMPADDR_REGEN_ADVANCE; 109 110 /* RTPREF_MEDIUM has to be 0! */ 111 #define RTPREF_HIGH 1 112 #define RTPREF_MEDIUM 0 113 #define RTPREF_LOW (-1) 114 #define RTPREF_RESERVED (-2) 115 #define RTPREF_INVALID (-3) /* internal */ 116 117 /* 118 * Receive Router Solicitation Message - just for routers. 119 * Router solicitation/advertisement is mostly managed by userland program 120 * (rtadvd) so here we have no function like nd6_ra_output(). 121 * 122 * Based on RFC 2461 123 */ 124 void 125 nd6_rs_input(struct mbuf *m, int off, int icmp6len) 126 { 127 struct ifnet *ifp = m->m_pkthdr.rcvif; 128 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 129 struct nd_router_solicit *nd_rs; 130 struct in6_addr saddr6 = ip6->ip6_src; 131 char *lladdr = NULL; 132 int lladdrlen = 0; 133 union nd_opts ndopts; 134 char ip6bufs[INET6_ADDRSTRLEN], ip6bufd[INET6_ADDRSTRLEN]; 135 136 /* 137 * Accept RS only when V_ip6_forwarding=1 and the interface has 138 * no ND6_IFF_ACCEPT_RTADV. 139 */ 140 if (!V_ip6_forwarding || ND_IFINFO(ifp)->flags & ND6_IFF_ACCEPT_RTADV) 141 goto freeit; 142 143 /* Sanity checks */ 144 if (ip6->ip6_hlim != 255) { 145 nd6log((LOG_ERR, 146 "nd6_rs_input: invalid hlim (%d) from %s to %s on %s\n", 147 ip6->ip6_hlim, ip6_sprintf(ip6bufs, &ip6->ip6_src), 148 ip6_sprintf(ip6bufd, &ip6->ip6_dst), if_name(ifp))); 149 goto bad; 150 } 151 152 /* 153 * Don't update the neighbor cache, if src = ::. 154 * This indicates that the src has no IP address assigned yet. 155 */ 156 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) 157 goto freeit; 158 159 #ifndef PULLDOWN_TEST 160 IP6_EXTHDR_CHECK(m, off, icmp6len,); 161 nd_rs = (struct nd_router_solicit *)((caddr_t)ip6 + off); 162 #else 163 IP6_EXTHDR_GET(nd_rs, struct nd_router_solicit *, m, off, icmp6len); 164 if (nd_rs == NULL) { 165 ICMP6STAT_INC(icp6s_tooshort); 166 return; 167 } 168 #endif 169 170 icmp6len -= sizeof(*nd_rs); 171 nd6_option_init(nd_rs + 1, icmp6len, &ndopts); 172 if (nd6_options(&ndopts) < 0) { 173 nd6log((LOG_INFO, 174 "nd6_rs_input: invalid ND option, ignored\n")); 175 /* nd6_options have incremented stats */ 176 goto freeit; 177 } 178 179 if (ndopts.nd_opts_src_lladdr) { 180 lladdr = (char *)(ndopts.nd_opts_src_lladdr + 1); 181 lladdrlen = ndopts.nd_opts_src_lladdr->nd_opt_len << 3; 182 } 183 184 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) { 185 nd6log((LOG_INFO, 186 "nd6_rs_input: lladdrlen mismatch for %s " 187 "(if %d, RS packet %d)\n", 188 ip6_sprintf(ip6bufs, &saddr6), 189 ifp->if_addrlen, lladdrlen - 2)); 190 goto bad; 191 } 192 193 nd6_cache_lladdr(ifp, &saddr6, lladdr, lladdrlen, ND_ROUTER_SOLICIT, 0); 194 195 freeit: 196 m_freem(m); 197 return; 198 199 bad: 200 ICMP6STAT_INC(icp6s_badrs); 201 m_freem(m); 202 } 203 204 /* 205 * Receive Router Advertisement Message. 206 * 207 * Based on RFC 2461 208 * TODO: on-link bit on prefix information 209 * TODO: ND_RA_FLAG_{OTHER,MANAGED} processing 210 */ 211 void 212 nd6_ra_input(struct mbuf *m, int off, int icmp6len) 213 { 214 struct ifnet *ifp = m->m_pkthdr.rcvif; 215 struct nd_ifinfo *ndi = ND_IFINFO(ifp); 216 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 217 struct nd_router_advert *nd_ra; 218 struct in6_addr saddr6 = ip6->ip6_src; 219 int mcast = 0; 220 union nd_opts ndopts; 221 struct nd_defrouter *dr; 222 char ip6bufs[INET6_ADDRSTRLEN], ip6bufd[INET6_ADDRSTRLEN]; 223 224 dr = NULL; 225 226 /* 227 * We only accept RAs only when the per-interface flag 228 * ND6_IFF_ACCEPT_RTADV is on the receiving interface. 229 */ 230 if (!(ndi->flags & ND6_IFF_ACCEPT_RTADV)) 231 goto freeit; 232 233 if (ip6->ip6_hlim != 255) { 234 nd6log((LOG_ERR, 235 "nd6_ra_input: invalid hlim (%d) from %s to %s on %s\n", 236 ip6->ip6_hlim, ip6_sprintf(ip6bufs, &ip6->ip6_src), 237 ip6_sprintf(ip6bufd, &ip6->ip6_dst), if_name(ifp))); 238 goto bad; 239 } 240 241 if (!IN6_IS_ADDR_LINKLOCAL(&saddr6)) { 242 nd6log((LOG_ERR, 243 "nd6_ra_input: src %s is not link-local\n", 244 ip6_sprintf(ip6bufs, &saddr6))); 245 goto bad; 246 } 247 248 #ifndef PULLDOWN_TEST 249 IP6_EXTHDR_CHECK(m, off, icmp6len,); 250 nd_ra = (struct nd_router_advert *)((caddr_t)ip6 + off); 251 #else 252 IP6_EXTHDR_GET(nd_ra, struct nd_router_advert *, m, off, icmp6len); 253 if (nd_ra == NULL) { 254 ICMP6STAT_INC(icp6s_tooshort); 255 return; 256 } 257 #endif 258 259 icmp6len -= sizeof(*nd_ra); 260 nd6_option_init(nd_ra + 1, icmp6len, &ndopts); 261 if (nd6_options(&ndopts) < 0) { 262 nd6log((LOG_INFO, 263 "nd6_ra_input: invalid ND option, ignored\n")); 264 /* nd6_options have incremented stats */ 265 goto freeit; 266 } 267 268 { 269 struct nd_defrouter dr0; 270 u_int32_t advreachable = nd_ra->nd_ra_reachable; 271 272 /* remember if this is a multicasted advertisement */ 273 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) 274 mcast = 1; 275 276 bzero(&dr0, sizeof(dr0)); 277 dr0.rtaddr = saddr6; 278 dr0.raflags = nd_ra->nd_ra_flags_reserved; 279 /* 280 * Effectively-disable routes from RA messages when 281 * ND6_IFF_NO_RADR enabled on the receiving interface or 282 * (ip6.forwarding == 1 && ip6.rfc6204w3 != 1). 283 */ 284 if (ndi->flags & ND6_IFF_NO_RADR) 285 dr0.rtlifetime = 0; 286 else if (V_ip6_forwarding && !V_ip6_rfc6204w3) 287 dr0.rtlifetime = 0; 288 else 289 dr0.rtlifetime = ntohs(nd_ra->nd_ra_router_lifetime); 290 dr0.expire = time_uptime + dr0.rtlifetime; 291 dr0.ifp = ifp; 292 /* unspecified or not? (RFC 2461 6.3.4) */ 293 if (advreachable) { 294 advreachable = ntohl(advreachable); 295 if (advreachable <= MAX_REACHABLE_TIME && 296 ndi->basereachable != advreachable) { 297 ndi->basereachable = advreachable; 298 ndi->reachable = ND_COMPUTE_RTIME(ndi->basereachable); 299 ndi->recalctm = V_nd6_recalc_reachtm_interval; /* reset */ 300 } 301 } 302 if (nd_ra->nd_ra_retransmit) 303 ndi->retrans = ntohl(nd_ra->nd_ra_retransmit); 304 if (nd_ra->nd_ra_curhoplimit) { 305 if (ndi->chlim < nd_ra->nd_ra_curhoplimit) 306 ndi->chlim = nd_ra->nd_ra_curhoplimit; 307 else if (ndi->chlim != nd_ra->nd_ra_curhoplimit) { 308 log(LOG_ERR, "RA with a lower CurHopLimit sent from " 309 "%s on %s (current = %d, received = %d). " 310 "Ignored.\n", ip6_sprintf(ip6bufs, &ip6->ip6_src), 311 if_name(ifp), ndi->chlim, nd_ra->nd_ra_curhoplimit); 312 } 313 } 314 dr = defrtrlist_update(&dr0); 315 } 316 317 /* 318 * prefix 319 */ 320 if (ndopts.nd_opts_pi) { 321 struct nd_opt_hdr *pt; 322 struct nd_opt_prefix_info *pi = NULL; 323 struct nd_prefixctl pr; 324 325 for (pt = (struct nd_opt_hdr *)ndopts.nd_opts_pi; 326 pt <= (struct nd_opt_hdr *)ndopts.nd_opts_pi_end; 327 pt = (struct nd_opt_hdr *)((caddr_t)pt + 328 (pt->nd_opt_len << 3))) { 329 if (pt->nd_opt_type != ND_OPT_PREFIX_INFORMATION) 330 continue; 331 pi = (struct nd_opt_prefix_info *)pt; 332 333 if (pi->nd_opt_pi_len != 4) { 334 nd6log((LOG_INFO, 335 "nd6_ra_input: invalid option " 336 "len %d for prefix information option, " 337 "ignored\n", pi->nd_opt_pi_len)); 338 continue; 339 } 340 341 if (128 < pi->nd_opt_pi_prefix_len) { 342 nd6log((LOG_INFO, 343 "nd6_ra_input: invalid prefix " 344 "len %d for prefix information option, " 345 "ignored\n", pi->nd_opt_pi_prefix_len)); 346 continue; 347 } 348 349 if (IN6_IS_ADDR_MULTICAST(&pi->nd_opt_pi_prefix) 350 || IN6_IS_ADDR_LINKLOCAL(&pi->nd_opt_pi_prefix)) { 351 nd6log((LOG_INFO, 352 "nd6_ra_input: invalid prefix " 353 "%s, ignored\n", 354 ip6_sprintf(ip6bufs, 355 &pi->nd_opt_pi_prefix))); 356 continue; 357 } 358 359 bzero(&pr, sizeof(pr)); 360 pr.ndpr_prefix.sin6_family = AF_INET6; 361 pr.ndpr_prefix.sin6_len = sizeof(pr.ndpr_prefix); 362 pr.ndpr_prefix.sin6_addr = pi->nd_opt_pi_prefix; 363 pr.ndpr_ifp = (struct ifnet *)m->m_pkthdr.rcvif; 364 365 pr.ndpr_raf_onlink = (pi->nd_opt_pi_flags_reserved & 366 ND_OPT_PI_FLAG_ONLINK) ? 1 : 0; 367 pr.ndpr_raf_auto = (pi->nd_opt_pi_flags_reserved & 368 ND_OPT_PI_FLAG_AUTO) ? 1 : 0; 369 pr.ndpr_plen = pi->nd_opt_pi_prefix_len; 370 pr.ndpr_vltime = ntohl(pi->nd_opt_pi_valid_time); 371 pr.ndpr_pltime = ntohl(pi->nd_opt_pi_preferred_time); 372 (void)prelist_update(&pr, dr, m, mcast); 373 } 374 } 375 if (dr != NULL) { 376 defrouter_rele(dr); 377 dr = NULL; 378 } 379 380 /* 381 * MTU 382 */ 383 if (ndopts.nd_opts_mtu && ndopts.nd_opts_mtu->nd_opt_mtu_len == 1) { 384 u_long mtu; 385 u_long maxmtu; 386 387 mtu = (u_long)ntohl(ndopts.nd_opts_mtu->nd_opt_mtu_mtu); 388 389 /* lower bound */ 390 if (mtu < IPV6_MMTU) { 391 nd6log((LOG_INFO, "nd6_ra_input: bogus mtu option " 392 "mtu=%lu sent from %s, ignoring\n", 393 mtu, ip6_sprintf(ip6bufs, &ip6->ip6_src))); 394 goto skip; 395 } 396 397 /* upper bound */ 398 maxmtu = (ndi->maxmtu && ndi->maxmtu < ifp->if_mtu) 399 ? ndi->maxmtu : ifp->if_mtu; 400 if (mtu <= maxmtu) { 401 int change = (ndi->linkmtu != mtu); 402 403 ndi->linkmtu = mtu; 404 if (change) /* in6_maxmtu may change */ 405 in6_setmaxmtu(); 406 } else { 407 nd6log((LOG_INFO, "nd6_ra_input: bogus mtu " 408 "mtu=%lu sent from %s; " 409 "exceeds maxmtu %lu, ignoring\n", 410 mtu, ip6_sprintf(ip6bufs, &ip6->ip6_src), maxmtu)); 411 } 412 } 413 414 skip: 415 416 /* 417 * Source link layer address 418 */ 419 { 420 char *lladdr = NULL; 421 int lladdrlen = 0; 422 423 if (ndopts.nd_opts_src_lladdr) { 424 lladdr = (char *)(ndopts.nd_opts_src_lladdr + 1); 425 lladdrlen = ndopts.nd_opts_src_lladdr->nd_opt_len << 3; 426 } 427 428 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) { 429 nd6log((LOG_INFO, 430 "nd6_ra_input: lladdrlen mismatch for %s " 431 "(if %d, RA packet %d)\n", ip6_sprintf(ip6bufs, &saddr6), 432 ifp->if_addrlen, lladdrlen - 2)); 433 goto bad; 434 } 435 436 nd6_cache_lladdr(ifp, &saddr6, lladdr, 437 lladdrlen, ND_ROUTER_ADVERT, 0); 438 439 /* 440 * Installing a link-layer address might change the state of the 441 * router's neighbor cache, which might also affect our on-link 442 * detection of adveritsed prefixes. 443 */ 444 pfxlist_onlink_check(); 445 } 446 447 freeit: 448 m_freem(m); 449 return; 450 451 bad: 452 ICMP6STAT_INC(icp6s_badra); 453 m_freem(m); 454 } 455 456 /* tell the change to user processes watching the routing socket. */ 457 static void 458 nd6_rtmsg(int cmd, struct rtentry *rt) 459 { 460 struct rt_addrinfo info; 461 struct ifnet *ifp; 462 struct ifaddr *ifa; 463 464 bzero((caddr_t)&info, sizeof(info)); 465 info.rti_info[RTAX_DST] = rt_key(rt); 466 info.rti_info[RTAX_GATEWAY] = rt->rt_gateway; 467 info.rti_info[RTAX_NETMASK] = rt_mask(rt); 468 ifp = rt->rt_ifp; 469 if (ifp != NULL) { 470 IF_ADDR_RLOCK(ifp); 471 ifa = TAILQ_FIRST(&ifp->if_addrhead); 472 info.rti_info[RTAX_IFP] = ifa->ifa_addr; 473 ifa_ref(ifa); 474 IF_ADDR_RUNLOCK(ifp); 475 info.rti_info[RTAX_IFA] = rt->rt_ifa->ifa_addr; 476 } else 477 ifa = NULL; 478 479 rt_missmsg_fib(cmd, &info, rt->rt_flags, 0, rt->rt_fibnum); 480 if (ifa != NULL) 481 ifa_free(ifa); 482 } 483 484 /* 485 * default router list proccessing sub routines 486 */ 487 488 static void 489 defrouter_addreq(struct nd_defrouter *new) 490 { 491 struct sockaddr_in6 def, mask, gate; 492 struct rtentry *newrt = NULL; 493 int error; 494 495 bzero(&def, sizeof(def)); 496 bzero(&mask, sizeof(mask)); 497 bzero(&gate, sizeof(gate)); 498 499 def.sin6_len = mask.sin6_len = gate.sin6_len = 500 sizeof(struct sockaddr_in6); 501 def.sin6_family = gate.sin6_family = AF_INET6; 502 gate.sin6_addr = new->rtaddr; 503 504 error = in6_rtrequest(RTM_ADD, (struct sockaddr *)&def, 505 (struct sockaddr *)&gate, (struct sockaddr *)&mask, 506 RTF_GATEWAY, &newrt, RT_DEFAULT_FIB); 507 if (newrt) { 508 nd6_rtmsg(RTM_ADD, newrt); /* tell user process */ 509 RTFREE(newrt); 510 } 511 if (error == 0) 512 new->installed = 1; 513 } 514 515 struct nd_defrouter * 516 defrouter_lookup_locked(struct in6_addr *addr, struct ifnet *ifp) 517 { 518 struct nd_defrouter *dr; 519 520 ND6_LOCK_ASSERT(); 521 TAILQ_FOREACH(dr, &V_nd_defrouter, dr_entry) 522 if (dr->ifp == ifp && IN6_ARE_ADDR_EQUAL(addr, &dr->rtaddr)) { 523 defrouter_ref(dr); 524 return (dr); 525 } 526 return (NULL); 527 } 528 529 struct nd_defrouter * 530 defrouter_lookup(struct in6_addr *addr, struct ifnet *ifp) 531 { 532 struct nd_defrouter *dr; 533 534 ND6_RLOCK(); 535 dr = defrouter_lookup_locked(addr, ifp); 536 ND6_RUNLOCK(); 537 return (dr); 538 } 539 540 void 541 defrouter_ref(struct nd_defrouter *dr) 542 { 543 544 refcount_acquire(&dr->refcnt); 545 } 546 547 void 548 defrouter_rele(struct nd_defrouter *dr) 549 { 550 551 if (refcount_release(&dr->refcnt)) 552 free(dr, M_IP6NDP); 553 } 554 555 /* 556 * Remove the default route for a given router. 557 * This is just a subroutine function for defrouter_select(), and should 558 * not be called from anywhere else. 559 */ 560 static void 561 defrouter_delreq(struct nd_defrouter *dr) 562 { 563 struct sockaddr_in6 def, mask, gate; 564 struct rtentry *oldrt = NULL; 565 566 bzero(&def, sizeof(def)); 567 bzero(&mask, sizeof(mask)); 568 bzero(&gate, sizeof(gate)); 569 570 def.sin6_len = mask.sin6_len = gate.sin6_len = 571 sizeof(struct sockaddr_in6); 572 def.sin6_family = gate.sin6_family = AF_INET6; 573 gate.sin6_addr = dr->rtaddr; 574 575 in6_rtrequest(RTM_DELETE, (struct sockaddr *)&def, 576 (struct sockaddr *)&gate, 577 (struct sockaddr *)&mask, RTF_GATEWAY, &oldrt, RT_DEFAULT_FIB); 578 if (oldrt) { 579 nd6_rtmsg(RTM_DELETE, oldrt); 580 RTFREE(oldrt); 581 } 582 583 dr->installed = 0; 584 } 585 586 /* 587 * Remove all default routes from default router list. 588 */ 589 void 590 defrouter_reset(void) 591 { 592 struct nd_defrouter *dr, **dra; 593 int count, i; 594 595 count = i = 0; 596 597 /* 598 * We can't delete routes with the ND lock held, so make a copy of the 599 * current default router list and use that when deleting routes. 600 */ 601 ND6_RLOCK(); 602 TAILQ_FOREACH(dr, &V_nd_defrouter, dr_entry) 603 count++; 604 ND6_RUNLOCK(); 605 606 dra = malloc(count * sizeof(*dra), M_TEMP, M_WAITOK | M_ZERO); 607 608 ND6_RLOCK(); 609 TAILQ_FOREACH(dr, &V_nd_defrouter, dr_entry) { 610 if (i == count) 611 break; 612 defrouter_ref(dr); 613 dra[i++] = dr; 614 } 615 ND6_RUNLOCK(); 616 617 for (i = 0; i < count && dra[i] != NULL; i++) { 618 defrouter_delreq(dra[i]); 619 defrouter_rele(dra[i]); 620 } 621 free(dra, M_TEMP); 622 623 /* 624 * XXX should we also nuke any default routers in the kernel, by 625 * going through them by rtalloc1()? 626 */ 627 } 628 629 /* 630 * Look up a matching default router list entry and remove it. Returns true if a 631 * matching entry was found, false otherwise. 632 */ 633 bool 634 defrouter_remove(struct in6_addr *addr, struct ifnet *ifp) 635 { 636 struct nd_defrouter *dr; 637 638 ND6_WLOCK(); 639 dr = defrouter_lookup_locked(addr, ifp); 640 if (dr == NULL) { 641 ND6_WUNLOCK(); 642 return (false); 643 } 644 645 defrouter_unlink(dr, NULL); 646 ND6_WUNLOCK(); 647 defrouter_del(dr); 648 defrouter_rele(dr); 649 return (true); 650 } 651 652 /* 653 * Remove a router from the global list and optionally stash it in a 654 * caller-supplied queue. 655 * 656 * The ND lock must be held. 657 */ 658 void 659 defrouter_unlink(struct nd_defrouter *dr, struct nd_drhead *drq) 660 { 661 662 ND6_WLOCK_ASSERT(); 663 TAILQ_REMOVE(&V_nd_defrouter, dr, dr_entry); 664 if (drq != NULL) 665 TAILQ_INSERT_TAIL(drq, dr, dr_entry); 666 } 667 668 void 669 defrouter_del(struct nd_defrouter *dr) 670 { 671 struct nd_defrouter *deldr = NULL; 672 struct nd_prefix *pr; 673 674 ND6_UNLOCK_ASSERT(); 675 676 /* 677 * Flush all the routing table entries that use the router 678 * as a next hop. 679 */ 680 if (ND_IFINFO(dr->ifp)->flags & ND6_IFF_ACCEPT_RTADV) 681 rt6_flush(&dr->rtaddr, dr->ifp); 682 683 if (dr->installed) { 684 deldr = dr; 685 defrouter_delreq(dr); 686 } 687 688 /* 689 * Also delete all the pointers to the router in each prefix lists. 690 */ 691 LIST_FOREACH(pr, &V_nd_prefix, ndpr_entry) { 692 struct nd_pfxrouter *pfxrtr; 693 if ((pfxrtr = pfxrtr_lookup(pr, dr)) != NULL) 694 pfxrtr_del(pfxrtr); 695 } 696 pfxlist_onlink_check(); 697 698 /* 699 * If the router is the primary one, choose a new one. 700 * Note that defrouter_select() will remove the current gateway 701 * from the routing table. 702 */ 703 if (deldr) 704 defrouter_select(); 705 706 /* 707 * Release the list reference. 708 */ 709 defrouter_rele(dr); 710 } 711 712 /* 713 * Default Router Selection according to Section 6.3.6 of RFC 2461 and 714 * draft-ietf-ipngwg-router-selection: 715 * 1) Routers that are reachable or probably reachable should be preferred. 716 * If we have more than one (probably) reachable router, prefer ones 717 * with the highest router preference. 718 * 2) When no routers on the list are known to be reachable or 719 * probably reachable, routers SHOULD be selected in a round-robin 720 * fashion, regardless of router preference values. 721 * 3) If the Default Router List is empty, assume that all 722 * destinations are on-link. 723 * 724 * We assume nd_defrouter is sorted by router preference value. 725 * Since the code below covers both with and without router preference cases, 726 * we do not need to classify the cases by ifdef. 727 * 728 * At this moment, we do not try to install more than one default router, 729 * even when the multipath routing is available, because we're not sure about 730 * the benefits for stub hosts comparing to the risk of making the code 731 * complicated and the possibility of introducing bugs. 732 */ 733 void 734 defrouter_select(void) 735 { 736 struct nd_defrouter *dr, *selected_dr, *installed_dr; 737 struct llentry *ln = NULL; 738 739 ND6_RLOCK(); 740 /* 741 * Let's handle easy case (3) first: 742 * If default router list is empty, there's nothing to be done. 743 */ 744 if (TAILQ_EMPTY(&V_nd_defrouter)) { 745 ND6_RUNLOCK(); 746 return; 747 } 748 749 /* 750 * Search for a (probably) reachable router from the list. 751 * We just pick up the first reachable one (if any), assuming that 752 * the ordering rule of the list described in defrtrlist_update(). 753 */ 754 selected_dr = installed_dr = NULL; 755 TAILQ_FOREACH(dr, &V_nd_defrouter, dr_entry) { 756 IF_AFDATA_RLOCK(dr->ifp); 757 if (selected_dr == NULL && 758 (ln = nd6_lookup(&dr->rtaddr, 0, dr->ifp)) && 759 ND6_IS_LLINFO_PROBREACH(ln)) { 760 selected_dr = dr; 761 defrouter_ref(selected_dr); 762 } 763 IF_AFDATA_RUNLOCK(dr->ifp); 764 if (ln != NULL) { 765 LLE_RUNLOCK(ln); 766 ln = NULL; 767 } 768 769 if (dr->installed) { 770 if (installed_dr == NULL) { 771 installed_dr = dr; 772 defrouter_ref(installed_dr); 773 } else { 774 /* this should not happen. warn for diagnosis. */ 775 log(LOG_ERR, 776 "defrouter_select: more than one router is installed\n"); 777 } 778 } 779 } 780 /* 781 * If none of the default routers was found to be reachable, 782 * round-robin the list regardless of preference. 783 * Otherwise, if we have an installed router, check if the selected 784 * (reachable) router should really be preferred to the installed one. 785 * We only prefer the new router when the old one is not reachable 786 * or when the new one has a really higher preference value. 787 */ 788 if (selected_dr == NULL) { 789 if (installed_dr == NULL || 790 TAILQ_NEXT(installed_dr, dr_entry) == NULL) 791 selected_dr = TAILQ_FIRST(&V_nd_defrouter); 792 else 793 selected_dr = TAILQ_NEXT(installed_dr, dr_entry); 794 defrouter_ref(selected_dr); 795 } else if (installed_dr != NULL) { 796 IF_AFDATA_RLOCK(installed_dr->ifp); 797 if ((ln = nd6_lookup(&installed_dr->rtaddr, 0, installed_dr->ifp)) && 798 ND6_IS_LLINFO_PROBREACH(ln) && 799 rtpref(selected_dr) <= rtpref(installed_dr)) { 800 defrouter_rele(selected_dr); 801 selected_dr = installed_dr; 802 } 803 IF_AFDATA_RUNLOCK(installed_dr->ifp); 804 if (ln != NULL) 805 LLE_RUNLOCK(ln); 806 } 807 ND6_RUNLOCK(); 808 809 /* 810 * If the selected router is different than the installed one, 811 * remove the installed router and install the selected one. 812 * Note that the selected router is never NULL here. 813 */ 814 if (installed_dr != selected_dr) { 815 if (installed_dr != NULL) { 816 defrouter_delreq(installed_dr); 817 defrouter_rele(installed_dr); 818 } 819 defrouter_addreq(selected_dr); 820 } 821 defrouter_rele(selected_dr); 822 } 823 824 /* 825 * for default router selection 826 * regards router-preference field as a 2-bit signed integer 827 */ 828 static int 829 rtpref(struct nd_defrouter *dr) 830 { 831 switch (dr->raflags & ND_RA_FLAG_RTPREF_MASK) { 832 case ND_RA_FLAG_RTPREF_HIGH: 833 return (RTPREF_HIGH); 834 case ND_RA_FLAG_RTPREF_MEDIUM: 835 case ND_RA_FLAG_RTPREF_RSV: 836 return (RTPREF_MEDIUM); 837 case ND_RA_FLAG_RTPREF_LOW: 838 return (RTPREF_LOW); 839 default: 840 /* 841 * This case should never happen. If it did, it would mean a 842 * serious bug of kernel internal. We thus always bark here. 843 * Or, can we even panic? 844 */ 845 log(LOG_ERR, "rtpref: impossible RA flag %x\n", dr->raflags); 846 return (RTPREF_INVALID); 847 } 848 /* NOTREACHED */ 849 } 850 851 static struct nd_defrouter * 852 defrtrlist_update(struct nd_defrouter *new) 853 { 854 struct nd_defrouter *dr, *n; 855 int oldpref; 856 857 if (new->rtlifetime == 0) { 858 defrouter_remove(&new->rtaddr, new->ifp); 859 return (NULL); 860 } 861 862 ND6_WLOCK(); 863 dr = defrouter_lookup_locked(&new->rtaddr, new->ifp); 864 if (dr != NULL) { 865 oldpref = rtpref(dr); 866 867 /* override */ 868 dr->raflags = new->raflags; /* XXX flag check */ 869 dr->rtlifetime = new->rtlifetime; 870 dr->expire = new->expire; 871 872 /* 873 * If the preference does not change, there's no need 874 * to sort the entries. Also make sure the selected 875 * router is still installed in the kernel. 876 */ 877 if (dr->installed && rtpref(new) == oldpref) { 878 ND6_WUNLOCK(); 879 return (dr); 880 } 881 882 /* 883 * The preferred router may have changed, so relocate this 884 * router. 885 */ 886 TAILQ_REMOVE(&V_nd_defrouter, dr, dr_entry); 887 n = dr; 888 } else { 889 n = malloc(sizeof(*n), M_IP6NDP, M_NOWAIT | M_ZERO); 890 if (n == NULL) { 891 ND6_WUNLOCK(); 892 return (NULL); 893 } 894 memcpy(n, new, sizeof(*n)); 895 /* Initialize with an extra reference for the caller. */ 896 refcount_init(&n->refcnt, 2); 897 } 898 899 /* 900 * Insert the new router in the Default Router List; 901 * The Default Router List should be in the descending order 902 * of router-preferece. Routers with the same preference are 903 * sorted in the arriving time order. 904 */ 905 906 /* insert at the end of the group */ 907 TAILQ_FOREACH(dr, &V_nd_defrouter, dr_entry) { 908 if (rtpref(n) > rtpref(dr)) 909 break; 910 } 911 if (dr != NULL) 912 TAILQ_INSERT_BEFORE(dr, n, dr_entry); 913 else 914 TAILQ_INSERT_TAIL(&V_nd_defrouter, n, dr_entry); 915 ND6_WUNLOCK(); 916 917 defrouter_select(); 918 919 return (n); 920 } 921 922 static struct nd_pfxrouter * 923 pfxrtr_lookup(struct nd_prefix *pr, struct nd_defrouter *dr) 924 { 925 struct nd_pfxrouter *search; 926 927 LIST_FOREACH(search, &pr->ndpr_advrtrs, pfr_entry) { 928 if (search->router == dr) 929 break; 930 } 931 932 return (search); 933 } 934 935 static void 936 pfxrtr_add(struct nd_prefix *pr, struct nd_defrouter *dr) 937 { 938 struct nd_pfxrouter *new; 939 940 new = malloc(sizeof(*new), M_IP6NDP, M_NOWAIT | M_ZERO); 941 if (new == NULL) 942 return; 943 new->router = dr; 944 defrouter_ref(dr); 945 946 LIST_INSERT_HEAD(&pr->ndpr_advrtrs, new, pfr_entry); 947 948 pfxlist_onlink_check(); 949 } 950 951 static void 952 pfxrtr_del(struct nd_pfxrouter *pfr) 953 { 954 955 LIST_REMOVE(pfr, pfr_entry); 956 defrouter_rele(pfr->router); 957 free(pfr, M_IP6NDP); 958 } 959 960 struct nd_prefix * 961 nd6_prefix_lookup(struct nd_prefixctl *key) 962 { 963 struct nd_prefix *search; 964 965 LIST_FOREACH(search, &V_nd_prefix, ndpr_entry) { 966 if (key->ndpr_ifp == search->ndpr_ifp && 967 key->ndpr_plen == search->ndpr_plen && 968 in6_are_prefix_equal(&key->ndpr_prefix.sin6_addr, 969 &search->ndpr_prefix.sin6_addr, key->ndpr_plen)) { 970 break; 971 } 972 } 973 974 return (search); 975 } 976 977 int 978 nd6_prelist_add(struct nd_prefixctl *pr, struct nd_defrouter *dr, 979 struct nd_prefix **newp) 980 { 981 struct nd_prefix *new = NULL; 982 int error = 0; 983 char ip6buf[INET6_ADDRSTRLEN]; 984 985 new = malloc(sizeof(*new), M_IP6NDP, M_NOWAIT | M_ZERO); 986 if (new == NULL) 987 return (ENOMEM); 988 new->ndpr_ifp = pr->ndpr_ifp; 989 new->ndpr_prefix = pr->ndpr_prefix; 990 new->ndpr_plen = pr->ndpr_plen; 991 new->ndpr_vltime = pr->ndpr_vltime; 992 new->ndpr_pltime = pr->ndpr_pltime; 993 new->ndpr_flags = pr->ndpr_flags; 994 if ((error = in6_init_prefix_ltimes(new)) != 0) { 995 free(new, M_IP6NDP); 996 return(error); 997 } 998 new->ndpr_lastupdate = time_uptime; 999 if (newp != NULL) 1000 *newp = new; 1001 1002 /* initialization */ 1003 LIST_INIT(&new->ndpr_advrtrs); 1004 in6_prefixlen2mask(&new->ndpr_mask, new->ndpr_plen); 1005 /* make prefix in the canonical form */ 1006 IN6_MASK_ADDR(&new->ndpr_prefix.sin6_addr, &new->ndpr_mask); 1007 1008 /* link ndpr_entry to nd_prefix list */ 1009 LIST_INSERT_HEAD(&V_nd_prefix, new, ndpr_entry); 1010 1011 /* ND_OPT_PI_FLAG_ONLINK processing */ 1012 if (new->ndpr_raf_onlink) { 1013 int e; 1014 1015 if ((e = nd6_prefix_onlink(new)) != 0) { 1016 nd6log((LOG_ERR, "nd6_prelist_add: failed to make " 1017 "the prefix %s/%d on-link on %s (errno=%d)\n", 1018 ip6_sprintf(ip6buf, &pr->ndpr_prefix.sin6_addr), 1019 pr->ndpr_plen, if_name(pr->ndpr_ifp), e)); 1020 /* proceed anyway. XXX: is it correct? */ 1021 } 1022 } 1023 1024 if (dr) 1025 pfxrtr_add(new, dr); 1026 1027 return 0; 1028 } 1029 1030 void 1031 prelist_remove(struct nd_prefix *pr) 1032 { 1033 struct nd_pfxrouter *pfr, *next; 1034 int e; 1035 char ip6buf[INET6_ADDRSTRLEN]; 1036 1037 /* make sure to invalidate the prefix until it is really freed. */ 1038 pr->ndpr_vltime = 0; 1039 pr->ndpr_pltime = 0; 1040 1041 /* 1042 * Though these flags are now meaningless, we'd rather keep the value 1043 * of pr->ndpr_raf_onlink and pr->ndpr_raf_auto not to confuse users 1044 * when executing "ndp -p". 1045 */ 1046 1047 if ((pr->ndpr_stateflags & NDPRF_ONLINK) != 0 && 1048 (e = nd6_prefix_offlink(pr)) != 0) { 1049 nd6log((LOG_ERR, "prelist_remove: failed to make %s/%d offlink " 1050 "on %s, errno=%d\n", 1051 ip6_sprintf(ip6buf, &pr->ndpr_prefix.sin6_addr), 1052 pr->ndpr_plen, if_name(pr->ndpr_ifp), e)); 1053 /* what should we do? */ 1054 } 1055 1056 if (pr->ndpr_refcnt > 0) 1057 return; /* notice here? */ 1058 1059 /* unlink ndpr_entry from nd_prefix list */ 1060 LIST_REMOVE(pr, ndpr_entry); 1061 1062 /* free list of routers that advertised the prefix */ 1063 LIST_FOREACH_SAFE(pfr, &pr->ndpr_advrtrs, pfr_entry, next) { 1064 pfxrtr_del(pfr); 1065 } 1066 free(pr, M_IP6NDP); 1067 1068 pfxlist_onlink_check(); 1069 } 1070 1071 /* 1072 * dr - may be NULL 1073 */ 1074 1075 static int 1076 prelist_update(struct nd_prefixctl *new, struct nd_defrouter *dr, 1077 struct mbuf *m, int mcast) 1078 { 1079 struct in6_ifaddr *ia6 = NULL, *ia6_match = NULL; 1080 struct ifaddr *ifa; 1081 struct ifnet *ifp = new->ndpr_ifp; 1082 struct nd_prefix *pr; 1083 int error = 0; 1084 int newprefix = 0; 1085 int auth; 1086 struct in6_addrlifetime lt6_tmp; 1087 char ip6buf[INET6_ADDRSTRLEN]; 1088 1089 auth = 0; 1090 if (m) { 1091 /* 1092 * Authenticity for NA consists authentication for 1093 * both IP header and IP datagrams, doesn't it ? 1094 */ 1095 #if defined(M_AUTHIPHDR) && defined(M_AUTHIPDGM) 1096 auth = ((m->m_flags & M_AUTHIPHDR) && 1097 (m->m_flags & M_AUTHIPDGM)); 1098 #endif 1099 } 1100 1101 if ((pr = nd6_prefix_lookup(new)) != NULL) { 1102 /* 1103 * nd6_prefix_lookup() ensures that pr and new have the same 1104 * prefix on a same interface. 1105 */ 1106 1107 /* 1108 * Update prefix information. Note that the on-link (L) bit 1109 * and the autonomous (A) bit should NOT be changed from 1 1110 * to 0. 1111 */ 1112 if (new->ndpr_raf_onlink == 1) 1113 pr->ndpr_raf_onlink = 1; 1114 if (new->ndpr_raf_auto == 1) 1115 pr->ndpr_raf_auto = 1; 1116 if (new->ndpr_raf_onlink) { 1117 pr->ndpr_vltime = new->ndpr_vltime; 1118 pr->ndpr_pltime = new->ndpr_pltime; 1119 (void)in6_init_prefix_ltimes(pr); /* XXX error case? */ 1120 pr->ndpr_lastupdate = time_uptime; 1121 } 1122 1123 if (new->ndpr_raf_onlink && 1124 (pr->ndpr_stateflags & NDPRF_ONLINK) == 0) { 1125 int e; 1126 1127 if ((e = nd6_prefix_onlink(pr)) != 0) { 1128 nd6log((LOG_ERR, 1129 "prelist_update: failed to make " 1130 "the prefix %s/%d on-link on %s " 1131 "(errno=%d)\n", 1132 ip6_sprintf(ip6buf, 1133 &pr->ndpr_prefix.sin6_addr), 1134 pr->ndpr_plen, if_name(pr->ndpr_ifp), e)); 1135 /* proceed anyway. XXX: is it correct? */ 1136 } 1137 } 1138 1139 if (dr && pfxrtr_lookup(pr, dr) == NULL) 1140 pfxrtr_add(pr, dr); 1141 } else { 1142 struct nd_prefix *newpr = NULL; 1143 1144 newprefix = 1; 1145 1146 if (new->ndpr_vltime == 0) 1147 goto end; 1148 if (new->ndpr_raf_onlink == 0 && new->ndpr_raf_auto == 0) 1149 goto end; 1150 1151 error = nd6_prelist_add(new, dr, &newpr); 1152 if (error != 0 || newpr == NULL) { 1153 nd6log((LOG_NOTICE, "prelist_update: " 1154 "nd6_prelist_add failed for %s/%d on %s " 1155 "errno=%d, returnpr=%p\n", 1156 ip6_sprintf(ip6buf, &new->ndpr_prefix.sin6_addr), 1157 new->ndpr_plen, if_name(new->ndpr_ifp), 1158 error, newpr)); 1159 goto end; /* we should just give up in this case. */ 1160 } 1161 1162 /* 1163 * XXX: from the ND point of view, we can ignore a prefix 1164 * with the on-link bit being zero. However, we need a 1165 * prefix structure for references from autoconfigured 1166 * addresses. Thus, we explicitly make sure that the prefix 1167 * itself expires now. 1168 */ 1169 if (newpr->ndpr_raf_onlink == 0) { 1170 newpr->ndpr_vltime = 0; 1171 newpr->ndpr_pltime = 0; 1172 in6_init_prefix_ltimes(newpr); 1173 } 1174 1175 pr = newpr; 1176 } 1177 1178 /* 1179 * Address autoconfiguration based on Section 5.5.3 of RFC 2462. 1180 * Note that pr must be non NULL at this point. 1181 */ 1182 1183 /* 5.5.3 (a). Ignore the prefix without the A bit set. */ 1184 if (!new->ndpr_raf_auto) 1185 goto end; 1186 1187 /* 1188 * 5.5.3 (b). the link-local prefix should have been ignored in 1189 * nd6_ra_input. 1190 */ 1191 1192 /* 5.5.3 (c). Consistency check on lifetimes: pltime <= vltime. */ 1193 if (new->ndpr_pltime > new->ndpr_vltime) { 1194 error = EINVAL; /* XXX: won't be used */ 1195 goto end; 1196 } 1197 1198 /* 1199 * 5.5.3 (d). If the prefix advertised is not equal to the prefix of 1200 * an address configured by stateless autoconfiguration already in the 1201 * list of addresses associated with the interface, and the Valid 1202 * Lifetime is not 0, form an address. We first check if we have 1203 * a matching prefix. 1204 * Note: we apply a clarification in rfc2462bis-02 here. We only 1205 * consider autoconfigured addresses while RFC2462 simply said 1206 * "address". 1207 */ 1208 IF_ADDR_RLOCK(ifp); 1209 TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) { 1210 struct in6_ifaddr *ifa6; 1211 u_int32_t remaininglifetime; 1212 1213 if (ifa->ifa_addr->sa_family != AF_INET6) 1214 continue; 1215 1216 ifa6 = (struct in6_ifaddr *)ifa; 1217 1218 /* 1219 * We only consider autoconfigured addresses as per rfc2462bis. 1220 */ 1221 if (!(ifa6->ia6_flags & IN6_IFF_AUTOCONF)) 1222 continue; 1223 1224 /* 1225 * Spec is not clear here, but I believe we should concentrate 1226 * on unicast (i.e. not anycast) addresses. 1227 * XXX: other ia6_flags? detached or duplicated? 1228 */ 1229 if ((ifa6->ia6_flags & IN6_IFF_ANYCAST) != 0) 1230 continue; 1231 1232 /* 1233 * Ignore the address if it is not associated with a prefix 1234 * or is associated with a prefix that is different from this 1235 * one. (pr is never NULL here) 1236 */ 1237 if (ifa6->ia6_ndpr != pr) 1238 continue; 1239 1240 if (ia6_match == NULL) /* remember the first one */ 1241 ia6_match = ifa6; 1242 1243 /* 1244 * An already autoconfigured address matched. Now that we 1245 * are sure there is at least one matched address, we can 1246 * proceed to 5.5.3. (e): update the lifetimes according to the 1247 * "two hours" rule and the privacy extension. 1248 * We apply some clarifications in rfc2462bis: 1249 * - use remaininglifetime instead of storedlifetime as a 1250 * variable name 1251 * - remove the dead code in the "two-hour" rule 1252 */ 1253 #define TWOHOUR (120*60) 1254 lt6_tmp = ifa6->ia6_lifetime; 1255 1256 if (lt6_tmp.ia6t_vltime == ND6_INFINITE_LIFETIME) 1257 remaininglifetime = ND6_INFINITE_LIFETIME; 1258 else if (time_uptime - ifa6->ia6_updatetime > 1259 lt6_tmp.ia6t_vltime) { 1260 /* 1261 * The case of "invalid" address. We should usually 1262 * not see this case. 1263 */ 1264 remaininglifetime = 0; 1265 } else 1266 remaininglifetime = lt6_tmp.ia6t_vltime - 1267 (time_uptime - ifa6->ia6_updatetime); 1268 1269 /* when not updating, keep the current stored lifetime. */ 1270 lt6_tmp.ia6t_vltime = remaininglifetime; 1271 1272 if (TWOHOUR < new->ndpr_vltime || 1273 remaininglifetime < new->ndpr_vltime) { 1274 lt6_tmp.ia6t_vltime = new->ndpr_vltime; 1275 } else if (remaininglifetime <= TWOHOUR) { 1276 if (auth) { 1277 lt6_tmp.ia6t_vltime = new->ndpr_vltime; 1278 } 1279 } else { 1280 /* 1281 * new->ndpr_vltime <= TWOHOUR && 1282 * TWOHOUR < remaininglifetime 1283 */ 1284 lt6_tmp.ia6t_vltime = TWOHOUR; 1285 } 1286 1287 /* The 2 hour rule is not imposed for preferred lifetime. */ 1288 lt6_tmp.ia6t_pltime = new->ndpr_pltime; 1289 1290 in6_init_address_ltimes(pr, <6_tmp); 1291 1292 /* 1293 * We need to treat lifetimes for temporary addresses 1294 * differently, according to 1295 * draft-ietf-ipv6-privacy-addrs-v2-01.txt 3.3 (1); 1296 * we only update the lifetimes when they are in the maximum 1297 * intervals. 1298 */ 1299 if ((ifa6->ia6_flags & IN6_IFF_TEMPORARY) != 0) { 1300 u_int32_t maxvltime, maxpltime; 1301 1302 if (V_ip6_temp_valid_lifetime > 1303 (u_int32_t)((time_uptime - ifa6->ia6_createtime) + 1304 V_ip6_desync_factor)) { 1305 maxvltime = V_ip6_temp_valid_lifetime - 1306 (time_uptime - ifa6->ia6_createtime) - 1307 V_ip6_desync_factor; 1308 } else 1309 maxvltime = 0; 1310 if (V_ip6_temp_preferred_lifetime > 1311 (u_int32_t)((time_uptime - ifa6->ia6_createtime) + 1312 V_ip6_desync_factor)) { 1313 maxpltime = V_ip6_temp_preferred_lifetime - 1314 (time_uptime - ifa6->ia6_createtime) - 1315 V_ip6_desync_factor; 1316 } else 1317 maxpltime = 0; 1318 1319 if (lt6_tmp.ia6t_vltime == ND6_INFINITE_LIFETIME || 1320 lt6_tmp.ia6t_vltime > maxvltime) { 1321 lt6_tmp.ia6t_vltime = maxvltime; 1322 } 1323 if (lt6_tmp.ia6t_pltime == ND6_INFINITE_LIFETIME || 1324 lt6_tmp.ia6t_pltime > maxpltime) { 1325 lt6_tmp.ia6t_pltime = maxpltime; 1326 } 1327 } 1328 ifa6->ia6_lifetime = lt6_tmp; 1329 ifa6->ia6_updatetime = time_uptime; 1330 } 1331 IF_ADDR_RUNLOCK(ifp); 1332 if (ia6_match == NULL && new->ndpr_vltime) { 1333 int ifidlen; 1334 1335 /* 1336 * 5.5.3 (d) (continued) 1337 * No address matched and the valid lifetime is non-zero. 1338 * Create a new address. 1339 */ 1340 1341 /* 1342 * Prefix Length check: 1343 * If the sum of the prefix length and interface identifier 1344 * length does not equal 128 bits, the Prefix Information 1345 * option MUST be ignored. The length of the interface 1346 * identifier is defined in a separate link-type specific 1347 * document. 1348 */ 1349 ifidlen = in6_if2idlen(ifp); 1350 if (ifidlen < 0) { 1351 /* this should not happen, so we always log it. */ 1352 log(LOG_ERR, "prelist_update: IFID undefined (%s)\n", 1353 if_name(ifp)); 1354 goto end; 1355 } 1356 if (ifidlen + pr->ndpr_plen != 128) { 1357 nd6log((LOG_INFO, 1358 "prelist_update: invalid prefixlen " 1359 "%d for %s, ignored\n", 1360 pr->ndpr_plen, if_name(ifp))); 1361 goto end; 1362 } 1363 1364 if ((ia6 = in6_ifadd(new, mcast)) != NULL) { 1365 /* 1366 * note that we should use pr (not new) for reference. 1367 */ 1368 pr->ndpr_refcnt++; 1369 ia6->ia6_ndpr = pr; 1370 1371 /* 1372 * RFC 3041 3.3 (2). 1373 * When a new public address is created as described 1374 * in RFC2462, also create a new temporary address. 1375 * 1376 * RFC 3041 3.5. 1377 * When an interface connects to a new link, a new 1378 * randomized interface identifier should be generated 1379 * immediately together with a new set of temporary 1380 * addresses. Thus, we specifiy 1 as the 2nd arg of 1381 * in6_tmpifadd(). 1382 */ 1383 if (V_ip6_use_tempaddr) { 1384 int e; 1385 if ((e = in6_tmpifadd(ia6, 1, 1)) != 0) { 1386 nd6log((LOG_NOTICE, "prelist_update: " 1387 "failed to create a temporary " 1388 "address, errno=%d\n", 1389 e)); 1390 } 1391 } 1392 ifa_free(&ia6->ia_ifa); 1393 1394 /* 1395 * A newly added address might affect the status 1396 * of other addresses, so we check and update it. 1397 * XXX: what if address duplication happens? 1398 */ 1399 pfxlist_onlink_check(); 1400 } else { 1401 /* just set an error. do not bark here. */ 1402 error = EADDRNOTAVAIL; /* XXX: might be unused. */ 1403 } 1404 } 1405 1406 end: 1407 return error; 1408 } 1409 1410 /* 1411 * A supplement function used in the on-link detection below; 1412 * detect if a given prefix has a (probably) reachable advertising router. 1413 * XXX: lengthy function name... 1414 */ 1415 static struct nd_pfxrouter * 1416 find_pfxlist_reachable_router(struct nd_prefix *pr) 1417 { 1418 struct nd_pfxrouter *pfxrtr; 1419 struct llentry *ln; 1420 int canreach; 1421 1422 LIST_FOREACH(pfxrtr, &pr->ndpr_advrtrs, pfr_entry) { 1423 IF_AFDATA_RLOCK(pfxrtr->router->ifp); 1424 ln = nd6_lookup(&pfxrtr->router->rtaddr, 0, pfxrtr->router->ifp); 1425 IF_AFDATA_RUNLOCK(pfxrtr->router->ifp); 1426 if (ln == NULL) 1427 continue; 1428 canreach = ND6_IS_LLINFO_PROBREACH(ln); 1429 LLE_RUNLOCK(ln); 1430 if (canreach) 1431 break; 1432 } 1433 return (pfxrtr); 1434 } 1435 1436 /* 1437 * Check if each prefix in the prefix list has at least one available router 1438 * that advertised the prefix (a router is "available" if its neighbor cache 1439 * entry is reachable or probably reachable). 1440 * If the check fails, the prefix may be off-link, because, for example, 1441 * we have moved from the network but the lifetime of the prefix has not 1442 * expired yet. So we should not use the prefix if there is another prefix 1443 * that has an available router. 1444 * But, if there is no prefix that has an available router, we still regards 1445 * all the prefixes as on-link. This is because we can't tell if all the 1446 * routers are simply dead or if we really moved from the network and there 1447 * is no router around us. 1448 */ 1449 void 1450 pfxlist_onlink_check() 1451 { 1452 struct nd_prefix *pr; 1453 struct in6_ifaddr *ifa; 1454 struct nd_defrouter *dr; 1455 struct nd_pfxrouter *pfxrtr = NULL; 1456 1457 /* 1458 * Check if there is a prefix that has a reachable advertising 1459 * router. 1460 */ 1461 LIST_FOREACH(pr, &V_nd_prefix, ndpr_entry) { 1462 if (pr->ndpr_raf_onlink && find_pfxlist_reachable_router(pr)) 1463 break; 1464 } 1465 1466 /* 1467 * If we have no such prefix, check whether we still have a router 1468 * that does not advertise any prefixes. 1469 */ 1470 if (pr == NULL) { 1471 ND6_RLOCK(); 1472 TAILQ_FOREACH(dr, &V_nd_defrouter, dr_entry) { 1473 struct nd_prefix *pr0; 1474 1475 LIST_FOREACH(pr0, &V_nd_prefix, ndpr_entry) { 1476 if ((pfxrtr = pfxrtr_lookup(pr0, dr)) != NULL) 1477 break; 1478 } 1479 if (pfxrtr != NULL) 1480 break; 1481 } 1482 ND6_RUNLOCK(); 1483 } 1484 if (pr != NULL || (!TAILQ_EMPTY(&V_nd_defrouter) && pfxrtr == NULL)) { 1485 /* 1486 * There is at least one prefix that has a reachable router, 1487 * or at least a router which probably does not advertise 1488 * any prefixes. The latter would be the case when we move 1489 * to a new link where we have a router that does not provide 1490 * prefixes and we configure an address by hand. 1491 * Detach prefixes which have no reachable advertising 1492 * router, and attach other prefixes. 1493 */ 1494 LIST_FOREACH(pr, &V_nd_prefix, ndpr_entry) { 1495 /* XXX: a link-local prefix should never be detached */ 1496 if (IN6_IS_ADDR_LINKLOCAL(&pr->ndpr_prefix.sin6_addr)) 1497 continue; 1498 1499 /* 1500 * we aren't interested in prefixes without the L bit 1501 * set. 1502 */ 1503 if (pr->ndpr_raf_onlink == 0) 1504 continue; 1505 1506 if (pr->ndpr_raf_auto == 0) 1507 continue; 1508 1509 if ((pr->ndpr_stateflags & NDPRF_DETACHED) == 0 && 1510 find_pfxlist_reachable_router(pr) == NULL) 1511 pr->ndpr_stateflags |= NDPRF_DETACHED; 1512 if ((pr->ndpr_stateflags & NDPRF_DETACHED) != 0 && 1513 find_pfxlist_reachable_router(pr) != NULL) 1514 pr->ndpr_stateflags &= ~NDPRF_DETACHED; 1515 } 1516 } else { 1517 /* there is no prefix that has a reachable router */ 1518 LIST_FOREACH(pr, &V_nd_prefix, ndpr_entry) { 1519 if (IN6_IS_ADDR_LINKLOCAL(&pr->ndpr_prefix.sin6_addr)) 1520 continue; 1521 1522 if (pr->ndpr_raf_onlink == 0) 1523 continue; 1524 1525 if (pr->ndpr_raf_auto == 0) 1526 continue; 1527 1528 if ((pr->ndpr_stateflags & NDPRF_DETACHED) != 0) 1529 pr->ndpr_stateflags &= ~NDPRF_DETACHED; 1530 } 1531 } 1532 1533 /* 1534 * Remove each interface route associated with a (just) detached 1535 * prefix, and reinstall the interface route for a (just) attached 1536 * prefix. Note that all attempt of reinstallation does not 1537 * necessarily success, when a same prefix is shared among multiple 1538 * interfaces. Such cases will be handled in nd6_prefix_onlink, 1539 * so we don't have to care about them. 1540 */ 1541 LIST_FOREACH(pr, &V_nd_prefix, ndpr_entry) { 1542 int e; 1543 char ip6buf[INET6_ADDRSTRLEN]; 1544 1545 if (IN6_IS_ADDR_LINKLOCAL(&pr->ndpr_prefix.sin6_addr)) 1546 continue; 1547 1548 if (pr->ndpr_raf_onlink == 0) 1549 continue; 1550 1551 if (pr->ndpr_raf_auto == 0) 1552 continue; 1553 1554 if ((pr->ndpr_stateflags & NDPRF_DETACHED) != 0 && 1555 (pr->ndpr_stateflags & NDPRF_ONLINK) != 0) { 1556 if ((e = nd6_prefix_offlink(pr)) != 0) { 1557 nd6log((LOG_ERR, 1558 "pfxlist_onlink_check: failed to " 1559 "make %s/%d offlink, errno=%d\n", 1560 ip6_sprintf(ip6buf, 1561 &pr->ndpr_prefix.sin6_addr), 1562 pr->ndpr_plen, e)); 1563 } 1564 } 1565 if ((pr->ndpr_stateflags & NDPRF_DETACHED) == 0 && 1566 (pr->ndpr_stateflags & NDPRF_ONLINK) == 0 && 1567 pr->ndpr_raf_onlink) { 1568 if ((e = nd6_prefix_onlink(pr)) != 0) { 1569 nd6log((LOG_ERR, 1570 "pfxlist_onlink_check: failed to " 1571 "make %s/%d onlink, errno=%d\n", 1572 ip6_sprintf(ip6buf, 1573 &pr->ndpr_prefix.sin6_addr), 1574 pr->ndpr_plen, e)); 1575 } 1576 } 1577 } 1578 1579 /* 1580 * Changes on the prefix status might affect address status as well. 1581 * Make sure that all addresses derived from an attached prefix are 1582 * attached, and that all addresses derived from a detached prefix are 1583 * detached. Note, however, that a manually configured address should 1584 * always be attached. 1585 * The precise detection logic is same as the one for prefixes. 1586 * 1587 * XXXRW: in6_ifaddrhead locking. 1588 */ 1589 TAILQ_FOREACH(ifa, &V_in6_ifaddrhead, ia_link) { 1590 if (!(ifa->ia6_flags & IN6_IFF_AUTOCONF)) 1591 continue; 1592 1593 if (ifa->ia6_ndpr == NULL) { 1594 /* 1595 * This can happen when we first configure the address 1596 * (i.e. the address exists, but the prefix does not). 1597 * XXX: complicated relationships... 1598 */ 1599 continue; 1600 } 1601 1602 if (find_pfxlist_reachable_router(ifa->ia6_ndpr)) 1603 break; 1604 } 1605 if (ifa) { 1606 TAILQ_FOREACH(ifa, &V_in6_ifaddrhead, ia_link) { 1607 if ((ifa->ia6_flags & IN6_IFF_AUTOCONF) == 0) 1608 continue; 1609 1610 if (ifa->ia6_ndpr == NULL) /* XXX: see above. */ 1611 continue; 1612 1613 if (find_pfxlist_reachable_router(ifa->ia6_ndpr)) { 1614 if (ifa->ia6_flags & IN6_IFF_DETACHED) { 1615 ifa->ia6_flags &= ~IN6_IFF_DETACHED; 1616 ifa->ia6_flags |= IN6_IFF_TENTATIVE; 1617 nd6_dad_start((struct ifaddr *)ifa, 0); 1618 } 1619 } else { 1620 ifa->ia6_flags |= IN6_IFF_DETACHED; 1621 } 1622 } 1623 } 1624 else { 1625 TAILQ_FOREACH(ifa, &V_in6_ifaddrhead, ia_link) { 1626 if ((ifa->ia6_flags & IN6_IFF_AUTOCONF) == 0) 1627 continue; 1628 1629 if (ifa->ia6_flags & IN6_IFF_DETACHED) { 1630 ifa->ia6_flags &= ~IN6_IFF_DETACHED; 1631 ifa->ia6_flags |= IN6_IFF_TENTATIVE; 1632 /* Do we need a delay in this case? */ 1633 nd6_dad_start((struct ifaddr *)ifa, 0); 1634 } 1635 } 1636 } 1637 } 1638 1639 static int 1640 nd6_prefix_onlink_rtrequest(struct nd_prefix *pr, struct ifaddr *ifa) 1641 { 1642 static struct sockaddr_dl null_sdl = {sizeof(null_sdl), AF_LINK}; 1643 struct rib_head *rnh; 1644 struct rtentry *rt; 1645 struct sockaddr_in6 mask6; 1646 u_long rtflags; 1647 int error, a_failure, fibnum; 1648 1649 /* 1650 * in6_ifinit() sets nd6_rtrequest to ifa_rtrequest for all ifaddrs. 1651 * ifa->ifa_rtrequest = nd6_rtrequest; 1652 */ 1653 bzero(&mask6, sizeof(mask6)); 1654 mask6.sin6_len = sizeof(mask6); 1655 mask6.sin6_addr = pr->ndpr_mask; 1656 rtflags = (ifa->ifa_flags & ~IFA_RTSELF) | RTF_UP; 1657 1658 a_failure = 0; 1659 for (fibnum = 0; fibnum < rt_numfibs; fibnum++) { 1660 1661 rt = NULL; 1662 error = in6_rtrequest(RTM_ADD, 1663 (struct sockaddr *)&pr->ndpr_prefix, ifa->ifa_addr, 1664 (struct sockaddr *)&mask6, rtflags, &rt, fibnum); 1665 if (error == 0) { 1666 KASSERT(rt != NULL, ("%s: in6_rtrequest return no " 1667 "error(%d) but rt is NULL, pr=%p, ifa=%p", __func__, 1668 error, pr, ifa)); 1669 1670 rnh = rt_tables_get_rnh(rt->rt_fibnum, AF_INET6); 1671 /* XXX what if rhn == NULL? */ 1672 RIB_WLOCK(rnh); 1673 RT_LOCK(rt); 1674 if (rt_setgate(rt, rt_key(rt), 1675 (struct sockaddr *)&null_sdl) == 0) { 1676 struct sockaddr_dl *dl; 1677 1678 dl = (struct sockaddr_dl *)rt->rt_gateway; 1679 dl->sdl_type = rt->rt_ifp->if_type; 1680 dl->sdl_index = rt->rt_ifp->if_index; 1681 } 1682 RIB_WUNLOCK(rnh); 1683 nd6_rtmsg(RTM_ADD, rt); 1684 RT_UNLOCK(rt); 1685 pr->ndpr_stateflags |= NDPRF_ONLINK; 1686 } else { 1687 char ip6buf[INET6_ADDRSTRLEN]; 1688 char ip6bufg[INET6_ADDRSTRLEN]; 1689 char ip6bufm[INET6_ADDRSTRLEN]; 1690 struct sockaddr_in6 *sin6; 1691 1692 sin6 = (struct sockaddr_in6 *)ifa->ifa_addr; 1693 nd6log((LOG_ERR, "nd6_prefix_onlink: failed to add " 1694 "route for a prefix (%s/%d) on %s, gw=%s, mask=%s, " 1695 "flags=%lx errno = %d\n", 1696 ip6_sprintf(ip6buf, &pr->ndpr_prefix.sin6_addr), 1697 pr->ndpr_plen, if_name(pr->ndpr_ifp), 1698 ip6_sprintf(ip6bufg, &sin6->sin6_addr), 1699 ip6_sprintf(ip6bufm, &mask6.sin6_addr), 1700 rtflags, error)); 1701 1702 /* Save last error to return, see rtinit(). */ 1703 a_failure = error; 1704 } 1705 1706 if (rt != NULL) { 1707 RT_LOCK(rt); 1708 RT_REMREF(rt); 1709 RT_UNLOCK(rt); 1710 } 1711 } 1712 1713 /* Return the last error we got. */ 1714 return (a_failure); 1715 } 1716 1717 static int 1718 nd6_prefix_onlink(struct nd_prefix *pr) 1719 { 1720 struct ifaddr *ifa; 1721 struct ifnet *ifp = pr->ndpr_ifp; 1722 struct nd_prefix *opr; 1723 int error = 0; 1724 char ip6buf[INET6_ADDRSTRLEN]; 1725 1726 /* sanity check */ 1727 if ((pr->ndpr_stateflags & NDPRF_ONLINK) != 0) { 1728 nd6log((LOG_ERR, 1729 "nd6_prefix_onlink: %s/%d is already on-link\n", 1730 ip6_sprintf(ip6buf, &pr->ndpr_prefix.sin6_addr), 1731 pr->ndpr_plen)); 1732 return (EEXIST); 1733 } 1734 1735 /* 1736 * Add the interface route associated with the prefix. Before 1737 * installing the route, check if there's the same prefix on another 1738 * interface, and the prefix has already installed the interface route. 1739 * Although such a configuration is expected to be rare, we explicitly 1740 * allow it. 1741 */ 1742 LIST_FOREACH(opr, &V_nd_prefix, ndpr_entry) { 1743 if (opr == pr) 1744 continue; 1745 1746 if ((opr->ndpr_stateflags & NDPRF_ONLINK) == 0) 1747 continue; 1748 1749 if (opr->ndpr_plen == pr->ndpr_plen && 1750 in6_are_prefix_equal(&pr->ndpr_prefix.sin6_addr, 1751 &opr->ndpr_prefix.sin6_addr, pr->ndpr_plen)) 1752 return (0); 1753 } 1754 1755 /* 1756 * We prefer link-local addresses as the associated interface address. 1757 */ 1758 /* search for a link-local addr */ 1759 ifa = (struct ifaddr *)in6ifa_ifpforlinklocal(ifp, 1760 IN6_IFF_NOTREADY | IN6_IFF_ANYCAST); 1761 if (ifa == NULL) { 1762 /* XXX: freebsd does not have ifa_ifwithaf */ 1763 IF_ADDR_RLOCK(ifp); 1764 TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) { 1765 if (ifa->ifa_addr->sa_family == AF_INET6) 1766 break; 1767 } 1768 if (ifa != NULL) 1769 ifa_ref(ifa); 1770 IF_ADDR_RUNLOCK(ifp); 1771 /* should we care about ia6_flags? */ 1772 } 1773 if (ifa == NULL) { 1774 /* 1775 * This can still happen, when, for example, we receive an RA 1776 * containing a prefix with the L bit set and the A bit clear, 1777 * after removing all IPv6 addresses on the receiving 1778 * interface. This should, of course, be rare though. 1779 */ 1780 nd6log((LOG_NOTICE, 1781 "nd6_prefix_onlink: failed to find any ifaddr" 1782 " to add route for a prefix(%s/%d) on %s\n", 1783 ip6_sprintf(ip6buf, &pr->ndpr_prefix.sin6_addr), 1784 pr->ndpr_plen, if_name(ifp))); 1785 return (0); 1786 } 1787 1788 error = nd6_prefix_onlink_rtrequest(pr, ifa); 1789 1790 if (ifa != NULL) 1791 ifa_free(ifa); 1792 1793 return (error); 1794 } 1795 1796 static int 1797 nd6_prefix_offlink(struct nd_prefix *pr) 1798 { 1799 int error = 0; 1800 struct ifnet *ifp = pr->ndpr_ifp; 1801 struct nd_prefix *opr; 1802 struct sockaddr_in6 sa6, mask6; 1803 struct rtentry *rt; 1804 char ip6buf[INET6_ADDRSTRLEN]; 1805 int fibnum, a_failure; 1806 1807 /* sanity check */ 1808 if ((pr->ndpr_stateflags & NDPRF_ONLINK) == 0) { 1809 nd6log((LOG_ERR, 1810 "nd6_prefix_offlink: %s/%d is already off-link\n", 1811 ip6_sprintf(ip6buf, &pr->ndpr_prefix.sin6_addr), 1812 pr->ndpr_plen)); 1813 return (EEXIST); 1814 } 1815 1816 bzero(&sa6, sizeof(sa6)); 1817 sa6.sin6_family = AF_INET6; 1818 sa6.sin6_len = sizeof(sa6); 1819 bcopy(&pr->ndpr_prefix.sin6_addr, &sa6.sin6_addr, 1820 sizeof(struct in6_addr)); 1821 bzero(&mask6, sizeof(mask6)); 1822 mask6.sin6_family = AF_INET6; 1823 mask6.sin6_len = sizeof(sa6); 1824 bcopy(&pr->ndpr_mask, &mask6.sin6_addr, sizeof(struct in6_addr)); 1825 1826 a_failure = 0; 1827 for (fibnum = 0; fibnum < rt_numfibs; fibnum++) { 1828 rt = NULL; 1829 error = in6_rtrequest(RTM_DELETE, (struct sockaddr *)&sa6, NULL, 1830 (struct sockaddr *)&mask6, 0, &rt, fibnum); 1831 if (error == 0) { 1832 /* report the route deletion to the routing socket. */ 1833 if (rt != NULL) 1834 nd6_rtmsg(RTM_DELETE, rt); 1835 } else { 1836 /* Save last error to return, see rtinit(). */ 1837 a_failure = error; 1838 } 1839 if (rt != NULL) { 1840 RTFREE(rt); 1841 } 1842 } 1843 error = a_failure; 1844 a_failure = 1; 1845 if (error == 0) { 1846 pr->ndpr_stateflags &= ~NDPRF_ONLINK; 1847 1848 /* 1849 * There might be the same prefix on another interface, 1850 * the prefix which could not be on-link just because we have 1851 * the interface route (see comments in nd6_prefix_onlink). 1852 * If there's one, try to make the prefix on-link on the 1853 * interface. 1854 */ 1855 LIST_FOREACH(opr, &V_nd_prefix, ndpr_entry) { 1856 if (opr == pr) 1857 continue; 1858 1859 if ((opr->ndpr_stateflags & NDPRF_ONLINK) != 0) 1860 continue; 1861 1862 /* 1863 * KAME specific: detached prefixes should not be 1864 * on-link. 1865 */ 1866 if ((opr->ndpr_stateflags & NDPRF_DETACHED) != 0) 1867 continue; 1868 1869 if (opr->ndpr_plen == pr->ndpr_plen && 1870 in6_are_prefix_equal(&pr->ndpr_prefix.sin6_addr, 1871 &opr->ndpr_prefix.sin6_addr, pr->ndpr_plen)) { 1872 int e; 1873 1874 if ((e = nd6_prefix_onlink(opr)) != 0) { 1875 nd6log((LOG_ERR, 1876 "nd6_prefix_offlink: failed to " 1877 "recover a prefix %s/%d from %s " 1878 "to %s (errno = %d)\n", 1879 ip6_sprintf(ip6buf, 1880 &opr->ndpr_prefix.sin6_addr), 1881 opr->ndpr_plen, if_name(ifp), 1882 if_name(opr->ndpr_ifp), e)); 1883 } else 1884 a_failure = 0; 1885 } 1886 } 1887 } else { 1888 /* XXX: can we still set the NDPRF_ONLINK flag? */ 1889 nd6log((LOG_ERR, 1890 "nd6_prefix_offlink: failed to delete route: " 1891 "%s/%d on %s (errno = %d)\n", 1892 ip6_sprintf(ip6buf, &sa6.sin6_addr), pr->ndpr_plen, 1893 if_name(ifp), error)); 1894 } 1895 1896 if (a_failure) 1897 lltable_prefix_free(AF_INET6, (struct sockaddr *)&sa6, 1898 (struct sockaddr *)&mask6, LLE_STATIC); 1899 1900 return (error); 1901 } 1902 1903 static struct in6_ifaddr * 1904 in6_ifadd(struct nd_prefixctl *pr, int mcast) 1905 { 1906 struct ifnet *ifp = pr->ndpr_ifp; 1907 struct ifaddr *ifa; 1908 struct in6_aliasreq ifra; 1909 struct in6_ifaddr *ia, *ib; 1910 int error, plen0; 1911 struct in6_addr mask; 1912 int prefixlen = pr->ndpr_plen; 1913 int updateflags; 1914 char ip6buf[INET6_ADDRSTRLEN]; 1915 1916 in6_prefixlen2mask(&mask, prefixlen); 1917 1918 /* 1919 * find a link-local address (will be interface ID). 1920 * Is it really mandatory? Theoretically, a global or a site-local 1921 * address can be configured without a link-local address, if we 1922 * have a unique interface identifier... 1923 * 1924 * it is not mandatory to have a link-local address, we can generate 1925 * interface identifier on the fly. we do this because: 1926 * (1) it should be the easiest way to find interface identifier. 1927 * (2) RFC2462 5.4 suggesting the use of the same interface identifier 1928 * for multiple addresses on a single interface, and possible shortcut 1929 * of DAD. we omitted DAD for this reason in the past. 1930 * (3) a user can prevent autoconfiguration of global address 1931 * by removing link-local address by hand (this is partly because we 1932 * don't have other way to control the use of IPv6 on an interface. 1933 * this has been our design choice - cf. NRL's "ifconfig auto"). 1934 * (4) it is easier to manage when an interface has addresses 1935 * with the same interface identifier, than to have multiple addresses 1936 * with different interface identifiers. 1937 */ 1938 ifa = (struct ifaddr *)in6ifa_ifpforlinklocal(ifp, 0); /* 0 is OK? */ 1939 if (ifa) 1940 ib = (struct in6_ifaddr *)ifa; 1941 else 1942 return NULL; 1943 1944 /* prefixlen + ifidlen must be equal to 128 */ 1945 plen0 = in6_mask2len(&ib->ia_prefixmask.sin6_addr, NULL); 1946 if (prefixlen != plen0) { 1947 ifa_free(ifa); 1948 nd6log((LOG_INFO, "in6_ifadd: wrong prefixlen for %s " 1949 "(prefix=%d ifid=%d)\n", 1950 if_name(ifp), prefixlen, 128 - plen0)); 1951 return NULL; 1952 } 1953 1954 /* make ifaddr */ 1955 in6_prepare_ifra(&ifra, &pr->ndpr_prefix.sin6_addr, &mask); 1956 1957 IN6_MASK_ADDR(&ifra.ifra_addr.sin6_addr, &mask); 1958 /* interface ID */ 1959 ifra.ifra_addr.sin6_addr.s6_addr32[0] |= 1960 (ib->ia_addr.sin6_addr.s6_addr32[0] & ~mask.s6_addr32[0]); 1961 ifra.ifra_addr.sin6_addr.s6_addr32[1] |= 1962 (ib->ia_addr.sin6_addr.s6_addr32[1] & ~mask.s6_addr32[1]); 1963 ifra.ifra_addr.sin6_addr.s6_addr32[2] |= 1964 (ib->ia_addr.sin6_addr.s6_addr32[2] & ~mask.s6_addr32[2]); 1965 ifra.ifra_addr.sin6_addr.s6_addr32[3] |= 1966 (ib->ia_addr.sin6_addr.s6_addr32[3] & ~mask.s6_addr32[3]); 1967 ifa_free(ifa); 1968 1969 /* lifetimes. */ 1970 ifra.ifra_lifetime.ia6t_vltime = pr->ndpr_vltime; 1971 ifra.ifra_lifetime.ia6t_pltime = pr->ndpr_pltime; 1972 1973 /* XXX: scope zone ID? */ 1974 1975 ifra.ifra_flags |= IN6_IFF_AUTOCONF; /* obey autoconf */ 1976 1977 /* 1978 * Make sure that we do not have this address already. This should 1979 * usually not happen, but we can still see this case, e.g., if we 1980 * have manually configured the exact address to be configured. 1981 */ 1982 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, 1983 &ifra.ifra_addr.sin6_addr); 1984 if (ifa != NULL) { 1985 ifa_free(ifa); 1986 /* this should be rare enough to make an explicit log */ 1987 log(LOG_INFO, "in6_ifadd: %s is already configured\n", 1988 ip6_sprintf(ip6buf, &ifra.ifra_addr.sin6_addr)); 1989 return (NULL); 1990 } 1991 1992 /* 1993 * Allocate ifaddr structure, link into chain, etc. 1994 * If we are going to create a new address upon receiving a multicasted 1995 * RA, we need to impose a random delay before starting DAD. 1996 * [draft-ietf-ipv6-rfc2462bis-02.txt, Section 5.4.2] 1997 */ 1998 updateflags = 0; 1999 if (mcast) 2000 updateflags |= IN6_IFAUPDATE_DADDELAY; 2001 if ((error = in6_update_ifa(ifp, &ifra, NULL, updateflags)) != 0) { 2002 nd6log((LOG_ERR, 2003 "in6_ifadd: failed to make ifaddr %s on %s (errno=%d)\n", 2004 ip6_sprintf(ip6buf, &ifra.ifra_addr.sin6_addr), 2005 if_name(ifp), error)); 2006 return (NULL); /* ifaddr must not have been allocated. */ 2007 } 2008 2009 ia = in6ifa_ifpwithaddr(ifp, &ifra.ifra_addr.sin6_addr); 2010 /* 2011 * XXXRW: Assumption of non-NULLness here might not be true with 2012 * fine-grained locking -- should we validate it? Or just return 2013 * earlier ifa rather than looking it up again? 2014 */ 2015 return (ia); /* this is always non-NULL and referenced. */ 2016 } 2017 2018 /* 2019 * ia0 - corresponding public address 2020 */ 2021 int 2022 in6_tmpifadd(const struct in6_ifaddr *ia0, int forcegen, int delay) 2023 { 2024 struct ifnet *ifp = ia0->ia_ifa.ifa_ifp; 2025 struct in6_ifaddr *newia; 2026 struct in6_aliasreq ifra; 2027 int error; 2028 int trylimit = 3; /* XXX: adhoc value */ 2029 int updateflags; 2030 u_int32_t randid[2]; 2031 time_t vltime0, pltime0; 2032 2033 in6_prepare_ifra(&ifra, &ia0->ia_addr.sin6_addr, 2034 &ia0->ia_prefixmask.sin6_addr); 2035 2036 ifra.ifra_addr = ia0->ia_addr; /* XXX: do we need this ? */ 2037 /* clear the old IFID */ 2038 IN6_MASK_ADDR(&ifra.ifra_addr.sin6_addr, 2039 &ifra.ifra_prefixmask.sin6_addr); 2040 2041 again: 2042 if (in6_get_tmpifid(ifp, (u_int8_t *)randid, 2043 (const u_int8_t *)&ia0->ia_addr.sin6_addr.s6_addr[8], forcegen)) { 2044 nd6log((LOG_NOTICE, "in6_tmpifadd: failed to find a good " 2045 "random IFID\n")); 2046 return (EINVAL); 2047 } 2048 ifra.ifra_addr.sin6_addr.s6_addr32[2] |= 2049 (randid[0] & ~(ifra.ifra_prefixmask.sin6_addr.s6_addr32[2])); 2050 ifra.ifra_addr.sin6_addr.s6_addr32[3] |= 2051 (randid[1] & ~(ifra.ifra_prefixmask.sin6_addr.s6_addr32[3])); 2052 2053 /* 2054 * in6_get_tmpifid() quite likely provided a unique interface ID. 2055 * However, we may still have a chance to see collision, because 2056 * there may be a time lag between generation of the ID and generation 2057 * of the address. So, we'll do one more sanity check. 2058 */ 2059 2060 if (in6_localip(&ifra.ifra_addr.sin6_addr) != 0) { 2061 if (trylimit-- > 0) { 2062 forcegen = 1; 2063 goto again; 2064 } 2065 2066 /* Give up. Something strange should have happened. */ 2067 nd6log((LOG_NOTICE, "in6_tmpifadd: failed to " 2068 "find a unique random IFID\n")); 2069 return (EEXIST); 2070 } 2071 2072 /* 2073 * The Valid Lifetime is the lower of the Valid Lifetime of the 2074 * public address or TEMP_VALID_LIFETIME. 2075 * The Preferred Lifetime is the lower of the Preferred Lifetime 2076 * of the public address or TEMP_PREFERRED_LIFETIME - 2077 * DESYNC_FACTOR. 2078 */ 2079 if (ia0->ia6_lifetime.ia6t_vltime != ND6_INFINITE_LIFETIME) { 2080 vltime0 = IFA6_IS_INVALID(ia0) ? 0 : 2081 (ia0->ia6_lifetime.ia6t_vltime - 2082 (time_uptime - ia0->ia6_updatetime)); 2083 if (vltime0 > V_ip6_temp_valid_lifetime) 2084 vltime0 = V_ip6_temp_valid_lifetime; 2085 } else 2086 vltime0 = V_ip6_temp_valid_lifetime; 2087 if (ia0->ia6_lifetime.ia6t_pltime != ND6_INFINITE_LIFETIME) { 2088 pltime0 = IFA6_IS_DEPRECATED(ia0) ? 0 : 2089 (ia0->ia6_lifetime.ia6t_pltime - 2090 (time_uptime - ia0->ia6_updatetime)); 2091 if (pltime0 > V_ip6_temp_preferred_lifetime - V_ip6_desync_factor){ 2092 pltime0 = V_ip6_temp_preferred_lifetime - 2093 V_ip6_desync_factor; 2094 } 2095 } else 2096 pltime0 = V_ip6_temp_preferred_lifetime - V_ip6_desync_factor; 2097 ifra.ifra_lifetime.ia6t_vltime = vltime0; 2098 ifra.ifra_lifetime.ia6t_pltime = pltime0; 2099 2100 /* 2101 * A temporary address is created only if this calculated Preferred 2102 * Lifetime is greater than REGEN_ADVANCE time units. 2103 */ 2104 if (ifra.ifra_lifetime.ia6t_pltime <= V_ip6_temp_regen_advance) 2105 return (0); 2106 2107 /* XXX: scope zone ID? */ 2108 2109 ifra.ifra_flags |= (IN6_IFF_AUTOCONF|IN6_IFF_TEMPORARY); 2110 2111 /* allocate ifaddr structure, link into chain, etc. */ 2112 updateflags = 0; 2113 if (delay) 2114 updateflags |= IN6_IFAUPDATE_DADDELAY; 2115 if ((error = in6_update_ifa(ifp, &ifra, NULL, updateflags)) != 0) 2116 return (error); 2117 2118 newia = in6ifa_ifpwithaddr(ifp, &ifra.ifra_addr.sin6_addr); 2119 if (newia == NULL) { /* XXX: can it happen? */ 2120 nd6log((LOG_ERR, 2121 "in6_tmpifadd: ifa update succeeded, but we got " 2122 "no ifaddr\n")); 2123 return (EINVAL); /* XXX */ 2124 } 2125 newia->ia6_ndpr = ia0->ia6_ndpr; 2126 newia->ia6_ndpr->ndpr_refcnt++; 2127 ifa_free(&newia->ia_ifa); 2128 2129 /* 2130 * A newly added address might affect the status of other addresses. 2131 * XXX: when the temporary address is generated with a new public 2132 * address, the onlink check is redundant. However, it would be safe 2133 * to do the check explicitly everywhere a new address is generated, 2134 * and, in fact, we surely need the check when we create a new 2135 * temporary address due to deprecation of an old temporary address. 2136 */ 2137 pfxlist_onlink_check(); 2138 2139 return (0); 2140 } 2141 2142 static int 2143 in6_init_prefix_ltimes(struct nd_prefix *ndpr) 2144 { 2145 if (ndpr->ndpr_pltime == ND6_INFINITE_LIFETIME) 2146 ndpr->ndpr_preferred = 0; 2147 else 2148 ndpr->ndpr_preferred = time_uptime + ndpr->ndpr_pltime; 2149 if (ndpr->ndpr_vltime == ND6_INFINITE_LIFETIME) 2150 ndpr->ndpr_expire = 0; 2151 else 2152 ndpr->ndpr_expire = time_uptime + ndpr->ndpr_vltime; 2153 2154 return 0; 2155 } 2156 2157 static void 2158 in6_init_address_ltimes(struct nd_prefix *new, struct in6_addrlifetime *lt6) 2159 { 2160 /* init ia6t_expire */ 2161 if (lt6->ia6t_vltime == ND6_INFINITE_LIFETIME) 2162 lt6->ia6t_expire = 0; 2163 else { 2164 lt6->ia6t_expire = time_uptime; 2165 lt6->ia6t_expire += lt6->ia6t_vltime; 2166 } 2167 2168 /* init ia6t_preferred */ 2169 if (lt6->ia6t_pltime == ND6_INFINITE_LIFETIME) 2170 lt6->ia6t_preferred = 0; 2171 else { 2172 lt6->ia6t_preferred = time_uptime; 2173 lt6->ia6t_preferred += lt6->ia6t_pltime; 2174 } 2175 } 2176 2177 /* 2178 * Delete all the routing table entries that use the specified gateway. 2179 * XXX: this function causes search through all entries of routing table, so 2180 * it shouldn't be called when acting as a router. 2181 */ 2182 void 2183 rt6_flush(struct in6_addr *gateway, struct ifnet *ifp) 2184 { 2185 2186 /* We'll care only link-local addresses */ 2187 if (!IN6_IS_ADDR_LINKLOCAL(gateway)) 2188 return; 2189 2190 /* XXX Do we really need to walk any but the default FIB? */ 2191 rt_foreach_fib_walk_del(AF_INET6, rt6_deleteroute, (void *)gateway); 2192 } 2193 2194 static int 2195 rt6_deleteroute(const struct rtentry *rt, void *arg) 2196 { 2197 #define SIN6(s) ((struct sockaddr_in6 *)s) 2198 struct in6_addr *gate = (struct in6_addr *)arg; 2199 2200 if (rt->rt_gateway == NULL || rt->rt_gateway->sa_family != AF_INET6) 2201 return (0); 2202 2203 if (!IN6_ARE_ADDR_EQUAL(gate, &SIN6(rt->rt_gateway)->sin6_addr)) { 2204 return (0); 2205 } 2206 2207 /* 2208 * Do not delete a static route. 2209 * XXX: this seems to be a bit ad-hoc. Should we consider the 2210 * 'cloned' bit instead? 2211 */ 2212 if ((rt->rt_flags & RTF_STATIC) != 0) 2213 return (0); 2214 2215 /* 2216 * We delete only host route. This means, in particular, we don't 2217 * delete default route. 2218 */ 2219 if ((rt->rt_flags & RTF_HOST) == 0) 2220 return (0); 2221 2222 return (1); 2223 #undef SIN6 2224 } 2225 2226 int 2227 nd6_setdefaultiface(int ifindex) 2228 { 2229 int error = 0; 2230 2231 if (ifindex < 0 || V_if_index < ifindex) 2232 return (EINVAL); 2233 if (ifindex != 0 && !ifnet_byindex(ifindex)) 2234 return (EINVAL); 2235 2236 if (V_nd6_defifindex != ifindex) { 2237 V_nd6_defifindex = ifindex; 2238 if (V_nd6_defifindex > 0) 2239 V_nd6_defifp = ifnet_byindex(V_nd6_defifindex); 2240 else 2241 V_nd6_defifp = NULL; 2242 2243 /* 2244 * Our current implementation assumes one-to-one maping between 2245 * interfaces and links, so it would be natural to use the 2246 * default interface as the default link. 2247 */ 2248 scope6_setdefault(V_nd6_defifp); 2249 } 2250 2251 return (error); 2252 } 2253