1 /* $NetBSD: nd6_rtr.c,v 1.136 2017/12/15 04:03:46 ozaki-r Exp $ */ 2 /* $KAME: nd6_rtr.c,v 1.95 2001/02/07 08:09:47 itojun 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 <sys/cdefs.h> 34 __KERNEL_RCSID(0, "$NetBSD: nd6_rtr.c,v 1.136 2017/12/15 04:03:46 ozaki-r Exp $"); 35 36 #ifdef _KERNEL_OPT 37 #include "opt_net_mpsafe.h" 38 #endif 39 40 #include <sys/param.h> 41 #include <sys/systm.h> 42 #include <sys/malloc.h> 43 #include <sys/mbuf.h> 44 #include <sys/socket.h> 45 #include <sys/sockio.h> 46 #include <sys/time.h> 47 #include <sys/kernel.h> 48 #include <sys/errno.h> 49 #include <sys/ioctl.h> 50 #include <sys/syslog.h> 51 #include <sys/cprng.h> 52 53 #include <net/if.h> 54 #include <net/if_types.h> 55 #include <net/if_dl.h> 56 57 #include <netinet/in.h> 58 #include <netinet6/in6_var.h> 59 #include <netinet6/in6_ifattach.h> 60 #include <netinet/ip6.h> 61 #include <netinet6/ip6_var.h> 62 #include <netinet6/nd6.h> 63 #include <netinet/icmp6.h> 64 #include <netinet6/icmp6_private.h> 65 #include <netinet6/scope6_var.h> 66 67 #include <net/net_osdep.h> 68 69 static int rtpref(struct nd_defrouter *); 70 static struct nd_defrouter *defrtrlist_update(struct nd_defrouter *); 71 static int prelist_update(struct nd_prefixctl *, struct nd_defrouter *, 72 struct mbuf *, int); 73 static struct in6_ifaddr *in6_ifadd(struct nd_prefixctl *, int, struct psref *); 74 static struct nd_pfxrouter *pfxrtr_lookup(struct nd_prefix *, 75 struct nd_defrouter *); 76 static void pfxrtr_add(struct nd_prefix *, struct nd_defrouter *); 77 static void pfxrtr_del(struct nd_pfxrouter *); 78 static struct nd_pfxrouter *find_pfxlist_reachable_router 79 (struct nd_prefix *); 80 81 static void defrouter_addreq(struct nd_defrouter *); 82 static void defrouter_delreq(struct nd_defrouter *); 83 84 static int in6_init_prefix_ltimes(struct nd_prefix *); 85 static void in6_init_address_ltimes(struct nd_prefix *, 86 struct in6_addrlifetime *); 87 static void purge_detached(struct ifnet *); 88 89 static int rt6_deleteroute_matcher(struct rtentry *, void *); 90 91 static int nd6_prelist_add(struct nd_prefixctl *, struct nd_defrouter *, 92 struct nd_prefix **); 93 static int nd6_prefix_onlink(struct nd_prefix *); 94 static int nd6_prefix_offlink(struct nd_prefix *); 95 static struct nd_prefix *nd6_prefix_lookup(struct nd_prefixctl *); 96 97 extern int nd6_recalc_reachtm_interval; 98 99 int ip6_use_tempaddr = 0; 100 101 int ip6_desync_factor; 102 u_int32_t ip6_temp_preferred_lifetime = DEF_TEMP_PREFERRED_LIFETIME; 103 u_int32_t ip6_temp_valid_lifetime = DEF_TEMP_VALID_LIFETIME; 104 int ip6_temp_regen_advance = TEMPADDR_REGEN_ADVANCE; 105 106 int nd6_numroutes = 0; 107 108 /* RTPREF_MEDIUM has to be 0! */ 109 #define RTPREF_HIGH 1 110 #define RTPREF_MEDIUM 0 111 #define RTPREF_LOW (-1) 112 #define RTPREF_RESERVED (-2) 113 #define RTPREF_INVALID (-3) /* internal */ 114 115 static inline bool 116 nd6_is_llinfo_probreach(struct nd_defrouter *dr) 117 { 118 struct llentry *ln = NULL; 119 120 ln = nd6_lookup(&dr->rtaddr, dr->ifp, false); 121 if (ln == NULL) 122 return false; 123 124 if (!ND6_IS_LLINFO_PROBREACH(ln)) { 125 LLE_RUNLOCK(ln); 126 return false; 127 } 128 129 LLE_RUNLOCK(ln); 130 return true; 131 } 132 133 /* 134 * Receive Router Solicitation Message - just for routers. 135 * Router solicitation/advertisement is mostly managed by a userland program 136 * (rtadvd) so here we have no function like nd6_ra_output(). 137 * 138 * Based on RFC 2461 139 */ 140 void 141 nd6_rs_input(struct mbuf *m, int off, int icmp6len) 142 { 143 struct ifnet *ifp; 144 struct nd_ifinfo *ndi; 145 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 146 struct nd_router_solicit *nd_rs; 147 struct in6_addr saddr6 = ip6->ip6_src; 148 char *lladdr = NULL; 149 int lladdrlen = 0; 150 union nd_opts ndopts; 151 struct psref psref; 152 char ip6bufs[INET6_ADDRSTRLEN], ip6bufd[INET6_ADDRSTRLEN]; 153 154 ifp = m_get_rcvif_psref(m, &psref); 155 if (ifp == NULL) 156 goto freeit; 157 158 ndi = ND_IFINFO(ifp); 159 160 /* If I'm not a router, ignore it. */ 161 if (nd6_accepts_rtadv(ndi) || !ip6_forwarding) 162 goto freeit; 163 164 /* Sanity checks */ 165 if (ip6->ip6_hlim != 255) { 166 nd6log(LOG_ERR, "invalid hlim (%d) from %s to %s on %s\n", 167 ip6->ip6_hlim, IN6_PRINT(ip6bufs, &ip6->ip6_src), 168 IN6_PRINT(ip6bufd, &ip6->ip6_dst), if_name(ifp)); 169 goto bad; 170 } 171 172 /* 173 * Don't update the neighbor cache, if src = ::. 174 * This indicates that the src has no IP address assigned yet. 175 */ 176 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) 177 goto freeit; 178 179 IP6_EXTHDR_GET(nd_rs, struct nd_router_solicit *, m, off, icmp6len); 180 if (nd_rs == NULL) { 181 ICMP6_STATINC(ICMP6_STAT_TOOSHORT); 182 return; 183 } 184 185 icmp6len -= sizeof(*nd_rs); 186 nd6_option_init(nd_rs + 1, icmp6len, &ndopts); 187 if (nd6_options(&ndopts) < 0) { 188 nd6log(LOG_INFO, "invalid ND option, ignored\n"); 189 /* nd6_options have incremented stats */ 190 goto freeit; 191 } 192 193 if (ndopts.nd_opts_src_lladdr) { 194 lladdr = (char *)(ndopts.nd_opts_src_lladdr + 1); 195 lladdrlen = ndopts.nd_opts_src_lladdr->nd_opt_len << 3; 196 } 197 198 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) { 199 nd6log(LOG_INFO, "lladdrlen mismatch for %s " 200 "(if %d, RS packet %d)\n", 201 IN6_PRINT(ip6bufs, &saddr6), 202 ifp->if_addrlen, lladdrlen - 2); 203 goto bad; 204 } 205 206 nd6_cache_lladdr(ifp, &saddr6, lladdr, lladdrlen, ND_ROUTER_SOLICIT, 0); 207 208 freeit: 209 m_put_rcvif_psref(ifp, &psref); 210 m_freem(m); 211 return; 212 213 bad: 214 ICMP6_STATINC(ICMP6_STAT_BADRS); 215 m_put_rcvif_psref(ifp, &psref); 216 m_freem(m); 217 } 218 219 /* 220 * Receive Router Advertisement Message. 221 * 222 * Based on RFC 2461 223 * TODO: on-link bit on prefix information 224 * TODO: ND_RA_FLAG_{OTHER,MANAGED} processing 225 */ 226 void 227 nd6_ra_input(struct mbuf *m, int off, int icmp6len) 228 { 229 struct ifnet *ifp; 230 struct nd_ifinfo *ndi; 231 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 232 struct nd_router_advert *nd_ra; 233 struct in6_addr saddr6 = ip6->ip6_src; 234 #if 0 235 struct in6_addr daddr6 = ip6->ip6_dst; 236 int flags; /* = nd_ra->nd_ra_flags_reserved; */ 237 int is_managed = ((flags & ND_RA_FLAG_MANAGED) != 0); 238 int is_other = ((flags & ND_RA_FLAG_OTHER) != 0); 239 #endif 240 int mcast = 0; 241 union nd_opts ndopts; 242 struct nd_defrouter *dr; 243 struct psref psref; 244 char ip6buf[INET6_ADDRSTRLEN], ip6buf2[INET6_ADDRSTRLEN]; 245 246 ifp = m_get_rcvif_psref(m, &psref); 247 if (ifp == NULL) 248 goto freeit; 249 250 ndi = ND_IFINFO(ifp); 251 /* 252 * We only accept RAs when 253 * the system-wide variable allows the acceptance, and the 254 * per-interface variable allows RAs on the receiving interface. 255 */ 256 if (!nd6_accepts_rtadv(ndi)) 257 goto freeit; 258 259 if (ip6->ip6_hlim != 255) { 260 nd6log(LOG_ERR, "invalid hlim (%d) from %s to %s on %s\n", 261 ip6->ip6_hlim, IN6_PRINT(ip6buf, &ip6->ip6_src), 262 IN6_PRINT(ip6buf2, &ip6->ip6_dst), if_name(ifp)); 263 goto bad; 264 } 265 266 if (!IN6_IS_ADDR_LINKLOCAL(&saddr6)) { 267 nd6log(LOG_ERR, "src %s is not link-local\n", 268 IN6_PRINT(ip6buf, &saddr6)); 269 goto bad; 270 } 271 272 IP6_EXTHDR_GET(nd_ra, struct nd_router_advert *, m, off, icmp6len); 273 if (nd_ra == NULL) { 274 ICMP6_STATINC(ICMP6_STAT_TOOSHORT); 275 m_put_rcvif_psref(ifp, &psref); 276 return; 277 } 278 279 icmp6len -= sizeof(*nd_ra); 280 nd6_option_init(nd_ra + 1, icmp6len, &ndopts); 281 if (nd6_options(&ndopts) < 0) { 282 nd6log(LOG_INFO, "invalid ND option, ignored\n"); 283 /* nd6_options have incremented stats */ 284 goto freeit; 285 } 286 287 { 288 struct nd_defrouter drtr; 289 u_int32_t advreachable = nd_ra->nd_ra_reachable; 290 291 /* remember if this is a multicasted advertisement */ 292 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) 293 mcast = 1; 294 295 memset(&drtr, 0, sizeof(drtr)); 296 drtr.rtaddr = saddr6; 297 drtr.flags = nd_ra->nd_ra_flags_reserved; 298 drtr.rtlifetime = ntohs(nd_ra->nd_ra_router_lifetime); 299 drtr.expire = time_uptime + drtr.rtlifetime; 300 drtr.ifp = ifp; 301 /* unspecified or not? (RFC 2461 6.3.4) */ 302 if (advreachable) { 303 NTOHL(advreachable); 304 if (advreachable <= MAX_REACHABLE_TIME && 305 ndi->basereachable != advreachable) { 306 ndi->basereachable = advreachable; 307 ndi->reachable = ND_COMPUTE_RTIME(ndi->basereachable); 308 ndi->recalctm = nd6_recalc_reachtm_interval; /* reset */ 309 } 310 } 311 if (nd_ra->nd_ra_retransmit) 312 ndi->retrans = ntohl(nd_ra->nd_ra_retransmit); 313 if (nd_ra->nd_ra_curhoplimit) { 314 if (ndi->chlim < nd_ra->nd_ra_curhoplimit) 315 ndi->chlim = nd_ra->nd_ra_curhoplimit; 316 else if (ndi->chlim != nd_ra->nd_ra_curhoplimit) 317 log(LOG_ERR, "nd_ra_input: lower CurHopLimit sent from " 318 "%s on %s (current=%d, received=%d), ignored\n", 319 IN6_PRINT(ip6buf, &ip6->ip6_src), 320 if_name(ifp), ndi->chlim, nd_ra->nd_ra_curhoplimit); 321 } 322 IFNET_LOCK(ifp); 323 ND6_WLOCK(); 324 dr = defrtrlist_update(&drtr); 325 } 326 327 /* 328 * prefix 329 */ 330 if (ndopts.nd_opts_pi) { 331 struct nd_opt_hdr *pt; 332 struct nd_opt_prefix_info *pi = NULL; 333 struct nd_prefixctl prc; 334 335 for (pt = (struct nd_opt_hdr *)ndopts.nd_opts_pi; 336 pt <= (struct nd_opt_hdr *)ndopts.nd_opts_pi_end; 337 pt = (struct nd_opt_hdr *)((char *)pt + 338 (pt->nd_opt_len << 3))) { 339 if (pt->nd_opt_type != ND_OPT_PREFIX_INFORMATION) 340 continue; 341 pi = (struct nd_opt_prefix_info *)pt; 342 343 if (pi->nd_opt_pi_len != 4) { 344 nd6log(LOG_INFO, "invalid option " 345 "len %d for prefix information option, " 346 "ignored\n", pi->nd_opt_pi_len); 347 continue; 348 } 349 350 if (128 < pi->nd_opt_pi_prefix_len) { 351 nd6log(LOG_INFO, "invalid prefix " 352 "len %d for prefix information option, " 353 "ignored\n", pi->nd_opt_pi_prefix_len); 354 continue; 355 } 356 357 if (IN6_IS_ADDR_MULTICAST(&pi->nd_opt_pi_prefix) 358 || IN6_IS_ADDR_LINKLOCAL(&pi->nd_opt_pi_prefix)) { 359 nd6log(LOG_INFO, 360 "invalid prefix %s, ignored\n", 361 IN6_PRINT(ip6buf, &pi->nd_opt_pi_prefix)); 362 continue; 363 } 364 365 memset(&prc, 0, sizeof(prc)); 366 sockaddr_in6_init(&prc.ndprc_prefix, 367 &pi->nd_opt_pi_prefix, 0, 0, 0); 368 prc.ndprc_ifp = ifp; 369 370 prc.ndprc_raf_onlink = (pi->nd_opt_pi_flags_reserved & 371 ND_OPT_PI_FLAG_ONLINK) ? 1 : 0; 372 prc.ndprc_raf_auto = (pi->nd_opt_pi_flags_reserved & 373 ND_OPT_PI_FLAG_AUTO) ? 1 : 0; 374 prc.ndprc_plen = pi->nd_opt_pi_prefix_len; 375 prc.ndprc_vltime = ntohl(pi->nd_opt_pi_valid_time); 376 prc.ndprc_pltime = ntohl(pi->nd_opt_pi_preferred_time); 377 378 (void)prelist_update(&prc, dr, m, mcast); 379 } 380 } 381 ND6_UNLOCK(); 382 IFNET_UNLOCK(ifp); 383 384 /* 385 * MTU 386 */ 387 if (ndopts.nd_opts_mtu && ndopts.nd_opts_mtu->nd_opt_mtu_len == 1) { 388 u_long mtu; 389 u_long maxmtu; 390 391 mtu = ntohl(ndopts.nd_opts_mtu->nd_opt_mtu_mtu); 392 393 /* lower bound */ 394 if (mtu < IPV6_MMTU) { 395 nd6log(LOG_INFO, "bogus mtu option " 396 "mtu=%lu sent from %s, ignoring\n", 397 mtu, IN6_PRINT(ip6buf, &ip6->ip6_src)); 398 goto skip; 399 } 400 401 /* upper bound */ 402 maxmtu = (ndi->maxmtu && ndi->maxmtu < ifp->if_mtu) 403 ? ndi->maxmtu : ifp->if_mtu; 404 if (mtu <= maxmtu) { 405 int change = (ndi->linkmtu != mtu); 406 407 ndi->linkmtu = mtu; 408 if (change) /* in6_maxmtu may change */ 409 in6_setmaxmtu(); 410 } else { 411 nd6log(LOG_INFO, 412 "bogus mtu mtu=%lu sent from %s; " 413 "exceeds maxmtu %lu, ignoring\n", 414 mtu, IN6_PRINT(ip6buf, &ip6->ip6_src), maxmtu); 415 } 416 } 417 418 skip: 419 420 /* 421 * Source link layer address 422 */ 423 { 424 char *lladdr = NULL; 425 int lladdrlen = 0; 426 427 if (ndopts.nd_opts_src_lladdr) { 428 lladdr = (char *)(ndopts.nd_opts_src_lladdr + 1); 429 lladdrlen = ndopts.nd_opts_src_lladdr->nd_opt_len << 3; 430 } 431 432 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) { 433 nd6log(LOG_INFO, "lladdrlen mismatch for %s " 434 "(if %d, RA packet %d)\n", IN6_PRINT(ip6buf, &saddr6), 435 ifp->if_addrlen, lladdrlen - 2); 436 goto bad; 437 } 438 439 nd6_cache_lladdr(ifp, &saddr6, lladdr, lladdrlen, ND_ROUTER_ADVERT, 0); 440 441 /* 442 * Installing a link-layer address might change the state of the 443 * router's neighbor cache, which might also affect our on-link 444 * detection of adveritsed prefixes. 445 */ 446 ND6_WLOCK(); 447 nd6_pfxlist_onlink_check(); 448 ND6_UNLOCK(); 449 } 450 451 freeit: 452 m_put_rcvif_psref(ifp, &psref); 453 m_freem(m); 454 return; 455 456 bad: 457 ICMP6_STATINC(ICMP6_STAT_BADRA); 458 m_put_rcvif_psref(ifp, &psref); 459 m_freem(m); 460 } 461 462 /* 463 * default router list processing sub routines 464 */ 465 static void 466 defrouter_addreq(struct nd_defrouter *newdr) 467 { 468 union { 469 struct sockaddr_in6 sin6; 470 struct sockaddr sa; 471 } def, mask, gate; 472 int error; 473 474 memset(&def, 0, sizeof(def)); 475 memset(&mask, 0, sizeof(mask)); 476 memset(&gate, 0,sizeof(gate)); /* for safety */ 477 478 def.sin6.sin6_len = mask.sin6.sin6_len = gate.sin6.sin6_len = 479 sizeof(struct sockaddr_in6); 480 def.sin6.sin6_family = mask.sin6.sin6_family = gate.sin6.sin6_family = AF_INET6; 481 gate.sin6.sin6_addr = newdr->rtaddr; 482 #ifndef SCOPEDROUTING 483 gate.sin6.sin6_scope_id = 0; /* XXX */ 484 #endif 485 486 #ifndef NET_MPSAFE 487 KASSERT(mutex_owned(softnet_lock)); 488 #endif 489 error = rtrequest_newmsg(RTM_ADD, &def.sa, &gate.sa, &mask.sa, 490 RTF_GATEWAY); 491 if (error == 0) { 492 nd6_numroutes++; 493 newdr->installed = 1; 494 } 495 return; 496 } 497 498 struct nd_defrouter * 499 nd6_defrouter_lookup(const struct in6_addr *addr, struct ifnet *ifp) 500 { 501 struct nd_defrouter *dr; 502 503 ND6_ASSERT_LOCK(); 504 505 ND_DEFROUTER_LIST_FOREACH(dr) { 506 if (dr->ifp == ifp && IN6_ARE_ADDR_EQUAL(addr, &dr->rtaddr)) 507 break; 508 } 509 510 return dr; /* search failed */ 511 } 512 513 void 514 nd6_defrtrlist_del(struct nd_defrouter *dr, struct in6_ifextra *ext) 515 { 516 struct nd_defrouter *deldr = NULL; 517 struct nd_prefix *pr; 518 struct nd_ifinfo *ndi; 519 520 ND6_ASSERT_WLOCK(); 521 522 if (ext == NULL) 523 ext = dr->ifp->if_afdata[AF_INET6]; 524 525 /* detach already in progress, can not do anything */ 526 if (ext == NULL) 527 return; 528 529 ndi = ext->nd_ifinfo; 530 531 /* 532 * Flush all the routing table entries that use the router 533 * as a next hop. 534 */ 535 /* XXX: better condition? */ 536 if (!ip6_forwarding && nd6_accepts_rtadv(ndi)) 537 nd6_rt_flush(&dr->rtaddr, dr->ifp); 538 539 if (dr->installed) { 540 deldr = dr; 541 defrouter_delreq(dr); 542 } 543 ND_DEFROUTER_LIST_REMOVE(dr); 544 545 /* 546 * Also delete all the pointers to the router in each prefix lists. 547 */ 548 ND_PREFIX_LIST_FOREACH(pr) { 549 struct nd_pfxrouter *pfxrtr; 550 if ((pfxrtr = pfxrtr_lookup(pr, dr)) != NULL) 551 pfxrtr_del(pfxrtr); 552 } 553 nd6_pfxlist_onlink_check(); 554 555 /* 556 * If the router is the primary one, choose a new one. 557 * Note that nd6_defrouter_select() will remove the current gateway 558 * from the routing table. 559 */ 560 if (deldr) 561 nd6_defrouter_select(); 562 563 ext->ndefrouters--; 564 if (ext->ndefrouters < 0) { 565 log(LOG_WARNING, "nd6_defrtrlist_del: negative count on %s\n", 566 dr->ifp->if_xname); 567 } 568 569 free(dr, M_IP6NDP); 570 } 571 572 /* 573 * Remove the default route for a given router. 574 * This is just a subroutine function for nd6_defrouter_select(), and should 575 * not be called from anywhere else. 576 */ 577 static void 578 defrouter_delreq(struct nd_defrouter *dr) 579 { 580 union { 581 struct sockaddr_in6 sin6; 582 struct sockaddr sa; 583 } def, mask, gw; 584 int error; 585 586 memset(&def, 0, sizeof(def)); 587 memset(&mask, 0, sizeof(mask)); 588 memset(&gw, 0, sizeof(gw)); /* for safety */ 589 590 def.sin6.sin6_len = mask.sin6.sin6_len = gw.sin6.sin6_len = 591 sizeof(struct sockaddr_in6); 592 def.sin6.sin6_family = mask.sin6.sin6_family = gw.sin6.sin6_family = AF_INET6; 593 gw.sin6.sin6_addr = dr->rtaddr; 594 #ifndef SCOPEDROUTING 595 gw.sin6.sin6_scope_id = 0; /* XXX */ 596 #endif 597 598 error = rtrequest_newmsg(RTM_DELETE, &def.sa, &gw.sa, &mask.sa, 599 RTF_GATEWAY); 600 if (error == 0) 601 nd6_numroutes--; 602 603 dr->installed = 0; 604 } 605 606 /* 607 * remove all default routes from default router list 608 */ 609 void 610 nd6_defrouter_reset(void) 611 { 612 struct nd_defrouter *dr; 613 614 ND6_ASSERT_WLOCK(); 615 616 ND_DEFROUTER_LIST_FOREACH(dr) 617 defrouter_delreq(dr); 618 619 /* 620 * XXX should we also nuke any default routers in the kernel, by 621 * going through them by rtalloc1()? 622 */ 623 } 624 625 /* 626 * Default Router Selection according to Section 6.3.6 of RFC 2461 and 627 * draft-ietf-ipngwg-router-selection: 628 * 1) Routers that are reachable or probably reachable should be preferred. 629 * If we have more than one (probably) reachable router, prefer ones 630 * with the highest router preference. 631 * 2) When no routers on the list are known to be reachable or 632 * probably reachable, routers SHOULD be selected in a round-robin 633 * fashion, regardless of router preference values. 634 * 3) If the Default Router List is empty, assume that all 635 * destinations are on-link. 636 * 637 * We assume nd_defrouter is sorted by router preference value. 638 * Since the code below covers both with and without router preference cases, 639 * we do not need to classify the cases by ifdef. 640 * 641 * At this moment, we do not try to install more than one default router, 642 * even when the multipath routing is available, because we're not sure about 643 * the benefits for stub hosts comparing to the risk of making the code 644 * complicated and the possibility of introducing bugs. 645 */ 646 void 647 nd6_defrouter_select(void) 648 { 649 struct nd_ifinfo *ndi; 650 struct nd_defrouter *dr, *selected_dr = NULL, *installed_dr = NULL; 651 652 ND6_ASSERT_WLOCK(); 653 654 /* 655 * This function should be called only when acting as an autoconfigured 656 * host. Although the remaining part of this function is not effective 657 * if the node is not an autoconfigured host, we explicitly exclude 658 * such cases here for safety. 659 */ 660 if (ip6_forwarding) { 661 nd6log(LOG_WARNING, "called unexpectedly (forwarding=%d, " 662 "accept_rtadv=%d)\n", ip6_forwarding, ip6_accept_rtadv); 663 return; 664 } 665 666 /* 667 * Let's handle easy case (3) first: 668 * If default router list is empty, there's nothing to be done. 669 */ 670 if (ND_DEFROUTER_LIST_EMPTY()) 671 return; 672 673 /* 674 * Search for a (probably) reachable router from the list. 675 * We just pick up the first reachable one (if any), assuming that 676 * the ordering rule of the list described in defrtrlist_update(). 677 */ 678 ND_DEFROUTER_LIST_FOREACH(dr) { 679 ndi = ND_IFINFO(dr->ifp); 680 if (nd6_accepts_rtadv(ndi)) 681 continue; 682 683 if (selected_dr == NULL && 684 nd6_is_llinfo_probreach(dr)) 685 selected_dr = dr; 686 687 if (dr->installed && !installed_dr) 688 installed_dr = dr; 689 else if (dr->installed && installed_dr) { 690 /* this should not happen. warn for diagnosis. */ 691 log(LOG_ERR, "nd6_defrouter_select: more than one router" 692 " is installed\n"); 693 } 694 } 695 /* 696 * If none of the default routers was found to be reachable, 697 * round-robin the list regardless of preference. 698 * Otherwise, if we have an installed router, check if the selected 699 * (reachable) router should really be preferred to the installed one. 700 * We only prefer the new router when the old one is not reachable 701 * or when the new one has a really higher preference value. 702 */ 703 if (selected_dr == NULL) { 704 if (installed_dr == NULL || 705 ND_DEFROUTER_LIST_NEXT(installed_dr) == NULL) 706 selected_dr = ND_DEFROUTER_LIST_FIRST(); 707 else 708 selected_dr = ND_DEFROUTER_LIST_NEXT(installed_dr); 709 } else if (installed_dr && 710 nd6_is_llinfo_probreach(installed_dr) && 711 rtpref(selected_dr) <= rtpref(installed_dr)) { 712 selected_dr = installed_dr; 713 } 714 715 /* 716 * If the selected router is different than the installed one, 717 * remove the installed router and install the selected one. 718 * Note that the selected router is never NULL here. 719 */ 720 if (installed_dr != selected_dr) { 721 if (installed_dr) 722 defrouter_delreq(installed_dr); 723 defrouter_addreq(selected_dr); 724 } 725 726 return; 727 } 728 729 /* 730 * for default router selection 731 * regards router-preference field as a 2-bit signed integer 732 */ 733 static int 734 rtpref(struct nd_defrouter *dr) 735 { 736 switch (dr->flags & ND_RA_FLAG_RTPREF_MASK) { 737 case ND_RA_FLAG_RTPREF_HIGH: 738 return (RTPREF_HIGH); 739 case ND_RA_FLAG_RTPREF_MEDIUM: 740 case ND_RA_FLAG_RTPREF_RSV: 741 return (RTPREF_MEDIUM); 742 case ND_RA_FLAG_RTPREF_LOW: 743 return (RTPREF_LOW); 744 default: 745 /* 746 * This case should never happen. If it did, it would mean a 747 * serious bug of kernel internal. We thus always bark here. 748 * Or, can we even panic? 749 */ 750 log(LOG_ERR, "rtpref: impossible RA flag %x\n", dr->flags); 751 return (RTPREF_INVALID); 752 } 753 /* NOTREACHED */ 754 } 755 756 static struct nd_defrouter * 757 defrtrlist_update(struct nd_defrouter *newdr) 758 { 759 struct nd_defrouter *dr, *n, *ret = NULL; 760 struct in6_ifextra *ext = newdr->ifp->if_afdata[AF_INET6]; 761 762 ND6_ASSERT_WLOCK(); 763 764 if ((dr = nd6_defrouter_lookup(&newdr->rtaddr, newdr->ifp)) != NULL) { 765 /* entry exists */ 766 if (newdr->rtlifetime == 0) { 767 nd6_defrtrlist_del(dr, ext); 768 dr = NULL; 769 } else { 770 int oldpref = rtpref(dr); 771 772 /* override */ 773 dr->flags = newdr->flags; /* xxx flag check */ 774 dr->rtlifetime = newdr->rtlifetime; 775 dr->expire = newdr->expire; 776 777 /* 778 * If the preference does not change, there's no need 779 * to sort the entries. 780 */ 781 if (rtpref(newdr) == oldpref) { 782 ret = dr; 783 goto out; 784 } 785 786 /* 787 * preferred router may be changed, so relocate 788 * this router. 789 * XXX: calling TAILQ_REMOVE directly is a bad manner. 790 * However, since nd6_defrtrlist_del() has many side 791 * effects, we intentionally do so here. 792 * nd6_defrouter_select() below will handle routing 793 * changes later. 794 */ 795 ND_DEFROUTER_LIST_REMOVE(dr); 796 n = dr; 797 goto insert; 798 } 799 ret = dr; 800 goto out; 801 } 802 803 if (ip6_maxifdefrouters >= 0 && ext->ndefrouters >= ip6_maxifdefrouters) 804 goto out; 805 806 /* entry does not exist */ 807 if (newdr->rtlifetime == 0) 808 goto out; 809 810 if (ip6_rtadv_maxroutes <= nd6_numroutes) { 811 ICMP6_STATINC(ICMP6_STAT_DROPPED_RAROUTE); 812 goto out; 813 } 814 815 n = (struct nd_defrouter *)malloc(sizeof(*n), M_IP6NDP, M_NOWAIT); 816 if (n == NULL) 817 goto out; 818 memset(n, 0, sizeof(*n)); 819 *n = *newdr; 820 821 insert: 822 /* 823 * Insert the new router in the Default Router List; 824 * The Default Router List should be in the descending order 825 * of router-preferece. Routers with the same preference are 826 * sorted in the arriving time order. 827 */ 828 829 /* insert at the end of the group */ 830 ND_DEFROUTER_LIST_FOREACH(dr) { 831 if (rtpref(n) > rtpref(dr)) 832 break; 833 } 834 if (dr) 835 ND_DEFROUTER_LIST_INSERT_BEFORE(dr, n); 836 else 837 ND_DEFROUTER_LIST_INSERT_TAIL(n); 838 839 nd6_defrouter_select(); 840 841 ext->ndefrouters++; 842 843 ret = n; 844 out: 845 return ret; 846 } 847 848 static struct nd_pfxrouter * 849 pfxrtr_lookup(struct nd_prefix *pr, struct nd_defrouter *dr) 850 { 851 struct nd_pfxrouter *search; 852 853 ND6_ASSERT_LOCK(); 854 855 LIST_FOREACH(search, &pr->ndpr_advrtrs, pfr_entry) { 856 if (search->router == dr) 857 break; 858 } 859 860 return (search); 861 } 862 863 static void 864 pfxrtr_add(struct nd_prefix *pr, struct nd_defrouter *dr) 865 { 866 struct nd_pfxrouter *newpfr; 867 868 ND6_ASSERT_WLOCK(); 869 870 newpfr = malloc(sizeof(*newpfr), M_IP6NDP, M_NOWAIT|M_ZERO); 871 if (newpfr == NULL) 872 return; 873 newpfr->router = dr; 874 875 LIST_INSERT_HEAD(&pr->ndpr_advrtrs, newpfr, pfr_entry); 876 877 nd6_pfxlist_onlink_check(); 878 } 879 880 static void 881 pfxrtr_del(struct nd_pfxrouter *pfr) 882 { 883 LIST_REMOVE(pfr, pfr_entry); 884 free(pfr, M_IP6NDP); 885 } 886 887 static struct nd_prefix * 888 nd6_prefix_lookup(struct nd_prefixctl *key) 889 { 890 struct nd_prefix *search; 891 892 ND_PREFIX_LIST_FOREACH(search) { 893 if (key->ndprc_ifp == search->ndpr_ifp && 894 key->ndprc_plen == search->ndpr_plen && 895 in6_are_prefix_equal(&key->ndprc_prefix.sin6_addr, 896 &search->ndpr_prefix.sin6_addr, key->ndprc_plen)) { 897 break; 898 } 899 } 900 901 return (search); 902 } 903 904 static void 905 purge_detached(struct ifnet *ifp) 906 { 907 struct nd_prefix *pr, *pr_next; 908 struct in6_ifaddr *ia; 909 struct ifaddr *ifa, *ifa_next; 910 911 restart: 912 ND6_ASSERT_WLOCK(); 913 914 ND_PREFIX_LIST_FOREACH_SAFE(pr, pr_next) { 915 int s; 916 917 /* 918 * This function is called when we need to make more room for 919 * new prefixes rather than keeping old, possibly stale ones. 920 * Detached prefixes would be a good candidate; if all routers 921 * that advertised the prefix expired, the prefix is also 922 * probably stale. 923 */ 924 if (pr->ndpr_ifp != ifp || 925 IN6_IS_ADDR_LINKLOCAL(&pr->ndpr_prefix.sin6_addr) || 926 ((pr->ndpr_stateflags & NDPRF_DETACHED) == 0 && 927 !LIST_EMPTY(&pr->ndpr_advrtrs))) 928 continue; 929 930 s = pserialize_read_enter(); 931 for (ifa = IFADDR_READER_FIRST(ifp); ifa; ifa = ifa_next) { 932 ifa_next = IFADDR_READER_NEXT(ifa); 933 if (ifa->ifa_addr->sa_family != AF_INET6) 934 continue; 935 ia = (struct in6_ifaddr *)ifa; 936 if ((ia->ia6_flags & IN6_IFF_AUTOCONF) == 937 IN6_IFF_AUTOCONF && ia->ia6_ndpr == pr) { 938 pserialize_read_exit(s); 939 ND6_UNLOCK(); 940 941 /* in6_purgeaddr may destroy pr. */ 942 in6_purgeaddr(ifa); 943 944 ND6_WLOCK(); 945 goto restart; 946 } 947 } 948 pserialize_read_exit(s); 949 950 KASSERT(pr->ndpr_refcnt == 0); 951 nd6_prelist_remove(pr); 952 } 953 } 954 955 static int 956 nd6_prelist_add(struct nd_prefixctl *prc, struct nd_defrouter *dr, 957 struct nd_prefix **newp) 958 { 959 struct nd_prefix *newpr = NULL; 960 int i; 961 int error; 962 struct in6_ifextra *ext = prc->ndprc_ifp->if_afdata[AF_INET6]; 963 964 ND6_ASSERT_WLOCK(); 965 966 if (ip6_maxifprefixes >= 0) { 967 if (ext->nprefixes >= ip6_maxifprefixes / 2) 968 purge_detached(prc->ndprc_ifp); 969 if (ext->nprefixes >= ip6_maxifprefixes) 970 return ENOMEM; 971 } 972 973 error = 0; 974 newpr = malloc(sizeof(*newpr), M_IP6NDP, M_NOWAIT|M_ZERO); 975 if (newpr == NULL) 976 return ENOMEM; 977 newpr->ndpr_ifp = prc->ndprc_ifp; 978 newpr->ndpr_prefix = prc->ndprc_prefix; 979 newpr->ndpr_plen = prc->ndprc_plen; 980 newpr->ndpr_vltime = prc->ndprc_vltime; 981 newpr->ndpr_pltime = prc->ndprc_pltime; 982 newpr->ndpr_flags = prc->ndprc_flags; 983 if ((error = in6_init_prefix_ltimes(newpr)) != 0) { 984 free(newpr, M_IP6NDP); 985 return(error); 986 } 987 newpr->ndpr_lastupdate = time_uptime; 988 if (newp != NULL) 989 *newp = newpr; 990 991 /* initialization */ 992 LIST_INIT(&newpr->ndpr_advrtrs); 993 in6_prefixlen2mask(&newpr->ndpr_mask, newpr->ndpr_plen); 994 /* make prefix in the canonical form */ 995 for (i = 0; i < 4; i++) { 996 newpr->ndpr_prefix.sin6_addr.s6_addr32[i] &= 997 newpr->ndpr_mask.s6_addr32[i]; 998 } 999 1000 /* link ndpr_entry to nd_prefix list */ 1001 ND_PREFIX_LIST_INSERT_HEAD(newpr); 1002 1003 /* ND_OPT_PI_FLAG_ONLINK processing */ 1004 if (newpr->ndpr_raf_onlink) { 1005 int e; 1006 1007 if ((e = nd6_prefix_onlink(newpr)) != 0) { 1008 char ip6buf[INET6_ADDRSTRLEN]; 1009 nd6log(LOG_ERR, "failed to make " 1010 "the prefix %s/%d on-link on %s (errno=%d)\n", 1011 IN6_PRINT(ip6buf, &prc->ndprc_prefix.sin6_addr), 1012 prc->ndprc_plen, if_name(prc->ndprc_ifp), e); 1013 /* proceed anyway. XXX: is it correct? */ 1014 } 1015 } 1016 1017 if (dr) 1018 pfxrtr_add(newpr, dr); 1019 1020 ext->nprefixes++; 1021 1022 return 0; 1023 } 1024 1025 void 1026 nd6_prefix_unref(struct nd_prefix *pr) 1027 { 1028 1029 ND6_WLOCK(); 1030 pr->ndpr_refcnt--; 1031 if (pr->ndpr_refcnt == 0) 1032 nd6_prelist_remove(pr); 1033 ND6_UNLOCK(); 1034 } 1035 1036 void 1037 nd6_invalidate_prefix(struct nd_prefix *pr) 1038 { 1039 int e; 1040 1041 ND6_ASSERT_WLOCK(); 1042 1043 /* make sure to invalidate the prefix until it is really freed. */ 1044 pr->ndpr_vltime = 0; 1045 pr->ndpr_pltime = 0; 1046 #if 0 1047 /* 1048 * Though these flags are now meaningless, we'd rather keep the value 1049 * not to confuse users when executing "ndp -p". 1050 */ 1051 pr->ndpr_raf_onlink = 0; 1052 pr->ndpr_raf_auto = 0; 1053 #endif 1054 if ((pr->ndpr_stateflags & NDPRF_ONLINK) != 0 && 1055 (e = nd6_prefix_offlink(pr)) != 0) { 1056 char ip6buf[INET6_ADDRSTRLEN]; 1057 nd6log(LOG_ERR, 1058 "failed to make %s/%d offlink on %s, errno=%d\n", 1059 IN6_PRINT(ip6buf, &pr->ndpr_prefix.sin6_addr), 1060 pr->ndpr_plen, if_name(pr->ndpr_ifp), e); 1061 /* what should we do? */ 1062 } 1063 } 1064 1065 void 1066 nd6_prelist_remove(struct nd_prefix *pr) 1067 { 1068 struct nd_pfxrouter *pfr, *next; 1069 struct in6_ifextra *ext = pr->ndpr_ifp->if_afdata[AF_INET6]; 1070 1071 ND6_ASSERT_WLOCK(); 1072 KASSERT(pr->ndpr_refcnt == 0); 1073 1074 nd6_invalidate_prefix(pr); 1075 1076 /* unlink ndpr_entry from nd_prefix list */ 1077 ND_PREFIX_LIST_REMOVE(pr); 1078 1079 /* free list of routers that adversed the prefix */ 1080 for (pfr = LIST_FIRST(&pr->ndpr_advrtrs); pfr != NULL; pfr = next) { 1081 next = LIST_NEXT(pfr, pfr_entry); 1082 1083 free(pfr, M_IP6NDP); 1084 } 1085 1086 if (ext) { 1087 ext->nprefixes--; 1088 if (ext->nprefixes < 0) { 1089 log(LOG_WARNING, "nd6_prelist_remove: negative count on " 1090 "%s\n", pr->ndpr_ifp->if_xname); 1091 } 1092 } 1093 1094 free(pr, M_IP6NDP); 1095 1096 nd6_pfxlist_onlink_check(); 1097 } 1098 1099 static int 1100 prelist_update(struct nd_prefixctl *newprc, 1101 struct nd_defrouter *dr, /* may be NULL */ 1102 struct mbuf *m, 1103 int mcast) 1104 { 1105 struct in6_ifaddr *ia6_match = NULL; 1106 struct ifaddr *ifa; 1107 struct ifnet *ifp = newprc->ndprc_ifp; 1108 struct nd_prefix *pr; 1109 int error = 0; 1110 int auth; 1111 struct in6_addrlifetime lt6_tmp; 1112 int ss; 1113 char ip6buf[INET6_ADDRSTRLEN]; 1114 1115 ND6_ASSERT_WLOCK(); 1116 1117 auth = 0; 1118 if (m) { 1119 /* 1120 * Authenticity for NA consists authentication for 1121 * both IP header and IP datagrams, doesn't it ? 1122 */ 1123 #if defined(M_AUTHIPHDR) && defined(M_AUTHIPDGM) 1124 auth = (m->m_flags & M_AUTHIPHDR 1125 && m->m_flags & M_AUTHIPDGM) ? 1 : 0; 1126 #endif 1127 } 1128 1129 if ((pr = nd6_prefix_lookup(newprc)) != NULL) { 1130 /* 1131 * nd6_prefix_lookup() ensures that pr and newprc have the same 1132 * prefix on a same interface. 1133 */ 1134 1135 /* 1136 * Update prefix information. Note that the on-link (L) bit 1137 * and the autonomous (A) bit should NOT be changed from 1 1138 * to 0. 1139 */ 1140 if (newprc->ndprc_raf_onlink == 1) 1141 pr->ndpr_raf_onlink = 1; 1142 if (newprc->ndprc_raf_auto == 1) 1143 pr->ndpr_raf_auto = 1; 1144 if (newprc->ndprc_raf_onlink) { 1145 pr->ndpr_vltime = newprc->ndprc_vltime; 1146 pr->ndpr_pltime = newprc->ndprc_pltime; 1147 (void)in6_init_prefix_ltimes(pr); /* XXX error case? */ 1148 pr->ndpr_lastupdate = time_uptime; 1149 } 1150 1151 if (newprc->ndprc_raf_onlink && 1152 (pr->ndpr_stateflags & NDPRF_ONLINK) == 0) { 1153 int e; 1154 1155 if ((e = nd6_prefix_onlink(pr)) != 0) { 1156 nd6log(LOG_ERR, 1157 "failed to make " 1158 "the prefix %s/%d on-link on %s " 1159 "(errno=%d)\n", 1160 IN6_PRINT(ip6buf, 1161 &pr->ndpr_prefix.sin6_addr), 1162 pr->ndpr_plen, if_name(pr->ndpr_ifp), e); 1163 /* proceed anyway. XXX: is it correct? */ 1164 } 1165 } 1166 1167 if (dr && pfxrtr_lookup(pr, dr) == NULL) 1168 pfxrtr_add(pr, dr); 1169 } else { 1170 struct nd_prefix *newpr = NULL; 1171 1172 if (newprc->ndprc_vltime == 0) 1173 goto end; 1174 if (newprc->ndprc_raf_onlink == 0 && newprc->ndprc_raf_auto == 0) 1175 goto end; 1176 1177 if (ip6_rtadv_maxroutes <= nd6_numroutes) { 1178 ICMP6_STATINC(ICMP6_STAT_DROPPED_RAROUTE); 1179 goto end; 1180 } 1181 1182 error = nd6_prelist_add(newprc, dr, &newpr); 1183 if (error != 0 || newpr == NULL) { 1184 nd6log(LOG_NOTICE, 1185 "nd6_prelist_add failed for %s/%d on %s " 1186 "errno=%d, returnpr=%p\n", 1187 IN6_PRINT(ip6buf, &newprc->ndprc_prefix.sin6_addr), 1188 newprc->ndprc_plen, if_name(newprc->ndprc_ifp), 1189 error, newpr); 1190 goto end; /* we should just give up in this case. */ 1191 } 1192 1193 /* 1194 * XXX: from the ND point of view, we can ignore a prefix 1195 * with the on-link bit being zero. However, we need a 1196 * prefix structure for references from autoconfigured 1197 * addresses. Thus, we explicitly make sure that the prefix 1198 * itself expires now. 1199 */ 1200 if (newpr->ndpr_raf_onlink == 0) { 1201 newpr->ndpr_vltime = 0; 1202 newpr->ndpr_pltime = 0; 1203 in6_init_prefix_ltimes(newpr); 1204 } 1205 1206 pr = newpr; 1207 } 1208 1209 /* 1210 * Address autoconfiguration based on Section 5.5.3 of RFC 2462. 1211 * Note that pr must be non NULL at this point. 1212 */ 1213 1214 /* 5.5.3 (a). Ignore the prefix without the A bit set. */ 1215 if (!newprc->ndprc_raf_auto) 1216 goto end; 1217 1218 /* 1219 * 5.5.3 (b). the link-local prefix should have been ignored in 1220 * nd6_ra_input. 1221 */ 1222 1223 /* 5.5.3 (c). Consistency check on lifetimes: pltime <= vltime. */ 1224 if (newprc->ndprc_pltime > newprc->ndprc_vltime) { 1225 error = EINVAL; /* XXX: won't be used */ 1226 goto end; 1227 } 1228 1229 /* 1230 * 5.5.3 (d). If the prefix advertised is not equal to the prefix of 1231 * an address configured by stateless autoconfiguration already in the 1232 * list of addresses associated with the interface, and the Valid 1233 * Lifetime is not 0, form an address. We first check if we have 1234 * a matching prefix. 1235 * Note: we apply a clarification in rfc2462bis-02 here. We only 1236 * consider autoconfigured addresses while RFC2462 simply said 1237 * "address". 1238 */ 1239 ss = pserialize_read_enter(); 1240 IFADDR_READER_FOREACH(ifa, ifp) { 1241 struct in6_ifaddr *ia6; 1242 u_int32_t remaininglifetime; 1243 1244 if (ifa->ifa_addr->sa_family != AF_INET6) 1245 continue; 1246 1247 ia6 = (struct in6_ifaddr *)ifa; 1248 1249 /* 1250 * We only consider autoconfigured addresses as per rfc2462bis. 1251 */ 1252 if (!(ia6->ia6_flags & IN6_IFF_AUTOCONF)) 1253 continue; 1254 1255 /* 1256 * Spec is not clear here, but I believe we should concentrate 1257 * on unicast (i.e. not anycast) addresses. 1258 * XXX: other ia6_flags? detached or duplicated? 1259 */ 1260 if ((ia6->ia6_flags & IN6_IFF_ANYCAST) != 0) 1261 continue; 1262 1263 /* 1264 * Ignore the address if it is not associated with a prefix 1265 * or is associated with a prefix that is different from this 1266 * one. (pr is never NULL here) 1267 */ 1268 if (ia6->ia6_ndpr != pr) 1269 continue; 1270 1271 if (ia6_match == NULL) /* remember the first one */ 1272 ia6_match = ia6; 1273 1274 /* 1275 * An already autoconfigured address matched. Now that we 1276 * are sure there is at least one matched address, we can 1277 * proceed to 5.5.3. (e): update the lifetimes according to the 1278 * "two hours" rule and the privacy extension. 1279 * We apply some clarifications in rfc2462bis: 1280 * - use remaininglifetime instead of storedlifetime as a 1281 * variable name 1282 * - remove the dead code in the "two-hour" rule 1283 */ 1284 #define TWOHOUR (120*60) 1285 lt6_tmp = ia6->ia6_lifetime; 1286 if (lt6_tmp.ia6t_vltime == ND6_INFINITE_LIFETIME) 1287 remaininglifetime = ND6_INFINITE_LIFETIME; 1288 else if (time_uptime - ia6->ia6_updatetime > 1289 lt6_tmp.ia6t_vltime) { 1290 /* 1291 * The case of "invalid" address. We should usually 1292 * not see this case. 1293 */ 1294 remaininglifetime = 0; 1295 } else 1296 remaininglifetime = lt6_tmp.ia6t_vltime - 1297 (time_uptime - ia6->ia6_updatetime); 1298 1299 /* when not updating, keep the current stored lifetime. */ 1300 lt6_tmp.ia6t_vltime = remaininglifetime; 1301 1302 if (TWOHOUR < newprc->ndprc_vltime || 1303 remaininglifetime < newprc->ndprc_vltime) { 1304 lt6_tmp.ia6t_vltime = newprc->ndprc_vltime; 1305 } else if (remaininglifetime <= TWOHOUR) { 1306 if (auth) 1307 lt6_tmp.ia6t_vltime = newprc->ndprc_vltime; 1308 } else { 1309 /* 1310 * newprc->ndprc_vltime <= TWOHOUR && 1311 * TWOHOUR < remaininglifetime 1312 */ 1313 lt6_tmp.ia6t_vltime = TWOHOUR; 1314 } 1315 1316 /* The 2 hour rule is not imposed for preferred lifetime. */ 1317 lt6_tmp.ia6t_pltime = newprc->ndprc_pltime; 1318 1319 in6_init_address_ltimes(pr, <6_tmp); 1320 1321 /* 1322 * We need to treat lifetimes for temporary addresses 1323 * differently, according to 1324 * draft-ietf-ipv6-privacy-addrs-v2-01.txt 3.3 (1); 1325 * we only update the lifetimes when they are in the maximum 1326 * intervals. 1327 */ 1328 if ((ia6->ia6_flags & IN6_IFF_TEMPORARY) != 0) { 1329 u_int32_t maxvltime, maxpltime; 1330 1331 if (ip6_temp_valid_lifetime > 1332 (u_int32_t)((time_uptime - ia6->ia6_createtime) + 1333 ip6_desync_factor)) { 1334 maxvltime = ip6_temp_valid_lifetime - 1335 (time_uptime - ia6->ia6_createtime) - 1336 ip6_desync_factor; 1337 } else 1338 maxvltime = 0; 1339 if (ip6_temp_preferred_lifetime > 1340 (u_int32_t)((time_uptime - ia6->ia6_createtime) + 1341 ip6_desync_factor)) { 1342 maxpltime = ip6_temp_preferred_lifetime - 1343 (time_uptime - ia6->ia6_createtime) - 1344 ip6_desync_factor; 1345 } else 1346 maxpltime = 0; 1347 1348 if (lt6_tmp.ia6t_vltime == ND6_INFINITE_LIFETIME || 1349 lt6_tmp.ia6t_vltime > maxvltime) { 1350 lt6_tmp.ia6t_vltime = maxvltime; 1351 } 1352 if (lt6_tmp.ia6t_pltime == ND6_INFINITE_LIFETIME || 1353 lt6_tmp.ia6t_pltime > maxpltime) { 1354 lt6_tmp.ia6t_pltime = maxpltime; 1355 } 1356 } 1357 1358 ia6->ia6_lifetime = lt6_tmp; 1359 ia6->ia6_updatetime = time_uptime; 1360 } 1361 pserialize_read_exit(ss); 1362 1363 if (ia6_match == NULL && newprc->ndprc_vltime) { 1364 int ifidlen; 1365 struct in6_ifaddr *ia6; 1366 struct psref psref; 1367 1368 /* 1369 * 5.5.3 (d) (continued) 1370 * No address matched and the valid lifetime is non-zero. 1371 * Create a new address. 1372 */ 1373 1374 /* 1375 * Prefix Length check: 1376 * If the sum of the prefix length and interface identifier 1377 * length does not equal 128 bits, the Prefix Information 1378 * option MUST be ignored. The length of the interface 1379 * identifier is defined in a separate link-type specific 1380 * document. 1381 */ 1382 ifidlen = in6_if2idlen(ifp); 1383 if (ifidlen < 0) { 1384 /* this should not happen, so we always log it. */ 1385 log(LOG_ERR, "%s: IFID undefined (%s)\n", 1386 __func__, if_name(ifp)); 1387 goto end; 1388 } 1389 if (ifidlen + pr->ndpr_plen != 128) { 1390 nd6log(LOG_INFO, 1391 "invalid prefixlen %d for %s, ignored\n", 1392 pr->ndpr_plen, if_name(ifp)); 1393 goto end; 1394 } 1395 1396 if ((ia6 = in6_ifadd(newprc, mcast, &psref)) != NULL) { 1397 /* 1398 * note that we should use pr (not newprc) for reference. 1399 */ 1400 pr->ndpr_refcnt++; 1401 ia6->ia6_ndpr = pr; 1402 1403 /* toggle onlink state if the address was assigned 1404 * a prefix route. */ 1405 if (ia6->ia_flags & IFA_ROUTE) 1406 pr->ndpr_stateflags |= NDPRF_ONLINK; 1407 1408 /* 1409 * draft-ietf-ipngwg-temp-addresses-v2-00 3.3 (2). 1410 * When a new public address is created as described 1411 * in RFC2462, also create a new temporary address. 1412 * 1413 * draft-ietf-ipngwg-temp-addresses-v2-00 3.5. 1414 * When an interface connects to a new link, a new 1415 * randomized interface identifier should be generated 1416 * immediately together with a new set of temporary 1417 * addresses. Thus, we specifiy 1 as the 2nd arg of 1418 * in6_tmpifadd(). 1419 */ 1420 if (ip6_use_tempaddr) { 1421 int e; 1422 if ((e = in6_tmpifadd(ia6, 1, 1)) != 0) { 1423 nd6log(LOG_NOTICE, 1424 "failed to create a temporary " 1425 "address, errno=%d\n", e); 1426 } 1427 } 1428 ia6_release(ia6, &psref); 1429 1430 /* 1431 * A newly added address might affect the status 1432 * of other addresses, so we check and update it. 1433 * XXX: what if address duplication happens? 1434 */ 1435 nd6_pfxlist_onlink_check(); 1436 } else { 1437 /* just set an error. do not bark here. */ 1438 error = EADDRNOTAVAIL; /* XXX: might be unused. */ 1439 } 1440 } 1441 1442 end: 1443 return error; 1444 } 1445 1446 /* 1447 * A supplement function used in the on-link detection below; 1448 * detect if a given prefix has a (probably) reachable advertising router. 1449 * XXX: lengthy function name... 1450 */ 1451 static struct nd_pfxrouter * 1452 find_pfxlist_reachable_router(struct nd_prefix *pr) 1453 { 1454 struct nd_pfxrouter *pfxrtr; 1455 1456 for (pfxrtr = LIST_FIRST(&pr->ndpr_advrtrs); pfxrtr; 1457 pfxrtr = LIST_NEXT(pfxrtr, pfr_entry)) { 1458 if (pfxrtr->router->ifp->if_flags & IFF_UP && 1459 pfxrtr->router->ifp->if_link_state != LINK_STATE_DOWN && 1460 nd6_is_llinfo_probreach(pfxrtr->router)) 1461 break; /* found */ 1462 } 1463 1464 return (pfxrtr); 1465 } 1466 1467 /* 1468 * Check if each prefix in the prefix list has at least one available router 1469 * that advertised the prefix (a router is "available" if its neighbor cache 1470 * entry is reachable or probably reachable). 1471 * If the check fails, the prefix may be off-link, because, for example, 1472 * we have moved from the network but the lifetime of the prefix has not 1473 * expired yet. So we should not use the prefix if there is another prefix 1474 * that has an available router. 1475 * But, if there is no prefix that has an available router, we still regards 1476 * all the prefixes as on-link. This is because we can't tell if all the 1477 * routers are simply dead or if we really moved from the network and there 1478 * is no router around us. 1479 */ 1480 void 1481 nd6_pfxlist_onlink_check(void) 1482 { 1483 struct nd_prefix *pr; 1484 struct in6_ifaddr *ia; 1485 struct nd_defrouter *dr; 1486 struct nd_pfxrouter *pfxrtr = NULL; 1487 int s; 1488 char ip6buf[INET6_ADDRSTRLEN]; 1489 1490 ND6_ASSERT_WLOCK(); 1491 1492 /* 1493 * Check if there is a prefix that has a reachable advertising 1494 * router. 1495 */ 1496 ND_PREFIX_LIST_FOREACH(pr) { 1497 if (pr->ndpr_raf_onlink && find_pfxlist_reachable_router(pr)) 1498 break; 1499 } 1500 /* 1501 * If we have no such prefix, check whether we still have a router 1502 * that does not advertise any prefixes. 1503 */ 1504 if (pr == NULL) { 1505 ND_DEFROUTER_LIST_FOREACH(dr) { 1506 struct nd_prefix *pr0; 1507 1508 ND_PREFIX_LIST_FOREACH(pr0) { 1509 if ((pfxrtr = pfxrtr_lookup(pr0, dr)) != NULL) 1510 break; 1511 } 1512 if (pfxrtr) 1513 break; 1514 } 1515 } 1516 if (pr != NULL || (!ND_DEFROUTER_LIST_EMPTY() && !pfxrtr)) { 1517 /* 1518 * There is at least one prefix that has a reachable router, 1519 * or at least a router which probably does not advertise 1520 * any prefixes. The latter would be the case when we move 1521 * to a new link where we have a router that does not provide 1522 * prefixes and we configure an address by hand. 1523 * Detach prefixes which have no reachable advertising 1524 * router, and attach other prefixes. 1525 */ 1526 ND_PREFIX_LIST_FOREACH(pr) { 1527 /* XXX: a link-local prefix should never be detached */ 1528 if (IN6_IS_ADDR_LINKLOCAL(&pr->ndpr_prefix.sin6_addr)) 1529 continue; 1530 1531 /* 1532 * we aren't interested in prefixes without the L bit 1533 * set. 1534 */ 1535 if (pr->ndpr_raf_onlink == 0) 1536 continue; 1537 1538 if ((pr->ndpr_stateflags & NDPRF_DETACHED) == 0 && 1539 find_pfxlist_reachable_router(pr) == NULL) 1540 pr->ndpr_stateflags |= NDPRF_DETACHED; 1541 if ((pr->ndpr_stateflags & NDPRF_DETACHED) != 0 && 1542 find_pfxlist_reachable_router(pr) != 0) 1543 pr->ndpr_stateflags &= ~NDPRF_DETACHED; 1544 } 1545 } else { 1546 /* there is no prefix that has a reachable router */ 1547 ND_PREFIX_LIST_FOREACH(pr) { 1548 if (IN6_IS_ADDR_LINKLOCAL(&pr->ndpr_prefix.sin6_addr)) 1549 continue; 1550 1551 if (pr->ndpr_raf_onlink == 0) 1552 continue; 1553 1554 if ((pr->ndpr_stateflags & NDPRF_DETACHED) != 0) 1555 pr->ndpr_stateflags &= ~NDPRF_DETACHED; 1556 } 1557 } 1558 1559 /* 1560 * Remove each interface route associated with a (just) detached 1561 * prefix, and reinstall the interface route for a (just) attached 1562 * prefix. Note that all attempt of reinstallation does not 1563 * necessarily success, when a same prefix is shared among multiple 1564 * interfaces. Such cases will be handled in nd6_prefix_onlink, 1565 * so we don't have to care about them. 1566 */ 1567 ND_PREFIX_LIST_FOREACH(pr) { 1568 int e; 1569 1570 if (IN6_IS_ADDR_LINKLOCAL(&pr->ndpr_prefix.sin6_addr)) 1571 continue; 1572 1573 if (pr->ndpr_raf_onlink == 0) 1574 continue; 1575 1576 if ((pr->ndpr_stateflags & NDPRF_DETACHED) != 0 && 1577 (pr->ndpr_stateflags & NDPRF_ONLINK) != 0) { 1578 if ((e = nd6_prefix_offlink(pr)) != 0) { 1579 nd6log(LOG_ERR, 1580 "failed to make %s/%d offlink, errno=%d\n", 1581 IN6_PRINT(ip6buf, 1582 &pr->ndpr_prefix.sin6_addr), 1583 pr->ndpr_plen, e); 1584 } 1585 } 1586 if ((pr->ndpr_stateflags & NDPRF_DETACHED) == 0 && 1587 (pr->ndpr_stateflags & NDPRF_ONLINK) == 0 && 1588 pr->ndpr_raf_onlink) { 1589 if ((e = nd6_prefix_onlink(pr)) != 0) { 1590 nd6log(LOG_ERR, 1591 "failed to make %s/%d onlink, errno=%d\n", 1592 IN6_PRINT(ip6buf, 1593 &pr->ndpr_prefix.sin6_addr), 1594 pr->ndpr_plen, e); 1595 } 1596 } 1597 } 1598 1599 /* 1600 * Changes on the prefix status might affect address status as well. 1601 * Make sure that all addresses derived from an attached prefix are 1602 * attached, and that all addresses derived from a detached prefix are 1603 * detached. Note, however, that a manually configured address should 1604 * always be attached. 1605 * The precise detection logic is same as the one for prefixes. 1606 */ 1607 s = pserialize_read_enter(); 1608 IN6_ADDRLIST_READER_FOREACH(ia) { 1609 if (!(ia->ia6_flags & IN6_IFF_AUTOCONF)) 1610 continue; 1611 1612 if (ia->ia6_ndpr == NULL) { 1613 /* 1614 * This can happen when we first configure the address 1615 * (i.e. the address exists, but the prefix does not). 1616 * XXX: complicated relationships... 1617 */ 1618 continue; 1619 } 1620 1621 if (find_pfxlist_reachable_router(ia->ia6_ndpr)) 1622 break; 1623 } 1624 pserialize_read_exit(s); 1625 1626 if (ia) { 1627 int bound = curlwp_bind(); 1628 1629 s = pserialize_read_enter(); 1630 IN6_ADDRLIST_READER_FOREACH(ia) { 1631 struct ifaddr *ifa = (struct ifaddr *)ia; 1632 struct psref psref; 1633 1634 if ((ia->ia6_flags & IN6_IFF_AUTOCONF) == 0) 1635 continue; 1636 1637 if (ia->ia6_ndpr == NULL) /* XXX: see above. */ 1638 continue; 1639 1640 ia6_acquire(ia, &psref); 1641 pserialize_read_exit(s); 1642 1643 if (find_pfxlist_reachable_router(ia->ia6_ndpr)) { 1644 if (ia->ia6_flags & IN6_IFF_DETACHED) { 1645 ia->ia6_flags &= ~IN6_IFF_DETACHED; 1646 ia->ia6_flags |= IN6_IFF_TENTATIVE; 1647 nd6_dad_start(ifa, 1648 0); 1649 /* We will notify the routing socket 1650 * of the DAD result, so no need to 1651 * here */ 1652 } 1653 } else { 1654 if ((ia->ia6_flags & IN6_IFF_DETACHED) == 0) { 1655 ia->ia6_flags |= IN6_IFF_DETACHED; 1656 rt_newaddrmsg(RTM_NEWADDR, 1657 ifa, 0, NULL); 1658 } 1659 } 1660 1661 s = pserialize_read_enter(); 1662 ia6_release(ia, &psref); 1663 } 1664 pserialize_read_exit(s); 1665 curlwp_bindx(bound); 1666 } 1667 else { 1668 int bound = curlwp_bind(); 1669 1670 s = pserialize_read_enter(); 1671 IN6_ADDRLIST_READER_FOREACH(ia) { 1672 if ((ia->ia6_flags & IN6_IFF_AUTOCONF) == 0) 1673 continue; 1674 1675 if (ia->ia6_flags & IN6_IFF_DETACHED) { 1676 struct ifaddr *ifa = (struct ifaddr *)ia; 1677 struct psref psref; 1678 1679 ia->ia6_flags &= ~IN6_IFF_DETACHED; 1680 ia->ia6_flags |= IN6_IFF_TENTATIVE; 1681 1682 ia6_acquire(ia, &psref); 1683 pserialize_read_exit(s); 1684 1685 /* Do we need a delay in this case? */ 1686 nd6_dad_start(ifa, 0); 1687 1688 s = pserialize_read_enter(); 1689 ia6_release(ia, &psref); 1690 } 1691 } 1692 pserialize_read_exit(s); 1693 curlwp_bindx(bound); 1694 } 1695 } 1696 1697 static int 1698 nd6_prefix_onlink(struct nd_prefix *pr) 1699 { 1700 struct ifaddr *ifa; 1701 struct ifnet *ifp = pr->ndpr_ifp; 1702 struct sockaddr_in6 mask6; 1703 struct nd_prefix *opr; 1704 u_long rtflags; 1705 int error = 0; 1706 struct psref psref; 1707 int bound; 1708 char ip6buf[INET6_ADDRSTRLEN]; 1709 char ip6bufp[INET6_ADDRSTRLEN], ip6bufm[INET6_ADDRSTRLEN]; 1710 1711 ND6_ASSERT_WLOCK(); 1712 1713 /* sanity check */ 1714 if ((pr->ndpr_stateflags & NDPRF_ONLINK) != 0) { 1715 nd6log(LOG_ERR, "%s/%d is already on-link\n", 1716 IN6_PRINT(ip6buf, &pr->ndpr_prefix.sin6_addr), 1717 pr->ndpr_plen); 1718 return (EEXIST); 1719 } 1720 1721 /* 1722 * Add the interface route associated with the prefix. Before 1723 * installing the route, check if there's the same prefix on another 1724 * interface, and the prefix has already installed the interface route. 1725 * Although such a configuration is expected to be rare, we explicitly 1726 * allow it. 1727 */ 1728 ND_PREFIX_LIST_FOREACH(opr) { 1729 if (opr == pr) 1730 continue; 1731 1732 if ((opr->ndpr_stateflags & NDPRF_ONLINK) == 0) 1733 continue; 1734 1735 if (opr->ndpr_plen == pr->ndpr_plen && 1736 in6_are_prefix_equal(&pr->ndpr_prefix.sin6_addr, 1737 &opr->ndpr_prefix.sin6_addr, pr->ndpr_plen)) 1738 return (0); 1739 } 1740 1741 /* 1742 * We prefer link-local addresses as the associated interface address. 1743 */ 1744 /* search for a link-local addr */ 1745 bound = curlwp_bind(); 1746 ifa = (struct ifaddr *)in6ifa_ifpforlinklocal_psref(ifp, 1747 IN6_IFF_NOTREADY | IN6_IFF_ANYCAST, &psref); 1748 if (ifa == NULL) { 1749 int s = pserialize_read_enter(); 1750 IFADDR_READER_FOREACH(ifa, ifp) { 1751 if (ifa->ifa_addr->sa_family == AF_INET6) 1752 break; 1753 } 1754 if (ifa != NULL) 1755 ifa_acquire(ifa, &psref); 1756 pserialize_read_exit(s); 1757 /* should we care about ia6_flags? */ 1758 } 1759 if (ifa == NULL) { 1760 /* 1761 * This can still happen, when, for example, we receive an RA 1762 * containing a prefix with the L bit set and the A bit clear, 1763 * after removing all IPv6 addresses on the receiving 1764 * interface. This should, of course, be rare though. 1765 */ 1766 nd6log(LOG_NOTICE, "failed to find any ifaddr" 1767 " to add route for a prefix(%s/%d) on %s\n", 1768 IN6_PRINT(ip6buf, &pr->ndpr_prefix.sin6_addr), 1769 pr->ndpr_plen, if_name(ifp)); 1770 curlwp_bindx(bound); 1771 return (0); 1772 } 1773 1774 /* 1775 * in6_ifinit() sets nd6_rtrequest to ifa_rtrequest for all ifaddrs. 1776 * ifa->ifa_rtrequest = nd6_rtrequest; 1777 */ 1778 memset(&mask6, 0, sizeof(mask6)); 1779 mask6.sin6_family = AF_INET6; 1780 mask6.sin6_len = sizeof(mask6); 1781 mask6.sin6_addr = pr->ndpr_mask; 1782 /* rtrequest() will probably set RTF_UP, but we're not sure. */ 1783 rtflags = ifa->ifa_flags | RTF_UP; 1784 if (nd6_need_cache(ifp)) { 1785 /* explicitly set in case ifa_flags does not set the flag. */ 1786 rtflags |= RTF_CONNECTED; 1787 } else { 1788 /* 1789 * explicitly clear the cloning bit in case ifa_flags sets it. 1790 */ 1791 rtflags &= ~RTF_CONNECTED; 1792 } 1793 error = rtrequest_newmsg(RTM_ADD, sin6tosa(&pr->ndpr_prefix), 1794 ifa->ifa_addr, sin6tosa(&mask6), rtflags); 1795 if (error == 0) { 1796 nd6_numroutes++; 1797 pr->ndpr_stateflags |= NDPRF_ONLINK; 1798 } else { 1799 nd6log(LOG_ERR, "failed to add route for a" 1800 " prefix (%s/%d) on %s, gw=%s, mask=%s, flags=%lx " 1801 "errno = %d\n", 1802 IN6_PRINT(ip6bufp, &pr->ndpr_prefix.sin6_addr), 1803 pr->ndpr_plen, if_name(ifp), 1804 IN6_PRINT(ip6buf, 1805 &((struct sockaddr_in6 *)ifa->ifa_addr)->sin6_addr), 1806 IN6_PRINT(ip6bufm, &mask6.sin6_addr), rtflags, error); 1807 } 1808 ifa_release(ifa, &psref); 1809 curlwp_bindx(bound); 1810 1811 return (error); 1812 } 1813 1814 static int 1815 nd6_prefix_offlink(struct nd_prefix *pr) 1816 { 1817 int error = 0; 1818 struct ifnet *ifp = pr->ndpr_ifp; 1819 struct nd_prefix *opr; 1820 struct sockaddr_in6 sa6, mask6; 1821 char ip6buf[INET6_ADDRSTRLEN]; 1822 1823 ND6_ASSERT_WLOCK(); 1824 1825 /* sanity check */ 1826 if ((pr->ndpr_stateflags & NDPRF_ONLINK) == 0) { 1827 nd6log(LOG_ERR, "%s/%d is already off-link\n", 1828 IN6_PRINT(ip6buf, &pr->ndpr_prefix.sin6_addr), 1829 pr->ndpr_plen); 1830 return (EEXIST); 1831 } 1832 1833 sockaddr_in6_init(&sa6, &pr->ndpr_prefix.sin6_addr, 0, 0, 0); 1834 sockaddr_in6_init(&mask6, &pr->ndpr_mask, 0, 0, 0); 1835 error = rtrequest_newmsg(RTM_DELETE, sin6tosa(&sa6), NULL, 1836 sin6tosa(&mask6), 0); 1837 if (error == 0) { 1838 pr->ndpr_stateflags &= ~NDPRF_ONLINK; 1839 nd6_numroutes--; 1840 1841 /* 1842 * There might be the same prefix on another interface, 1843 * the prefix which could not be on-link just because we have 1844 * the interface route (see comments in nd6_prefix_onlink). 1845 * If there's one, try to make the prefix on-link on the 1846 * interface. 1847 */ 1848 ND_PREFIX_LIST_FOREACH(opr) { 1849 if (opr == pr) 1850 continue; 1851 1852 if ((opr->ndpr_stateflags & NDPRF_ONLINK) != 0) 1853 continue; 1854 1855 /* 1856 * KAME specific: detached prefixes should not be 1857 * on-link. 1858 */ 1859 if ((opr->ndpr_stateflags & NDPRF_DETACHED) != 0) 1860 continue; 1861 1862 if (opr->ndpr_plen == pr->ndpr_plen && 1863 in6_are_prefix_equal(&pr->ndpr_prefix.sin6_addr, 1864 &opr->ndpr_prefix.sin6_addr, pr->ndpr_plen)) { 1865 int e; 1866 1867 if ((e = nd6_prefix_onlink(opr)) != 0) { 1868 nd6log(LOG_ERR, "failed to " 1869 "recover a prefix %s/%d from %s " 1870 "to %s (errno = %d)\n", 1871 IN6_PRINT(ip6buf, 1872 &opr->ndpr_prefix.sin6_addr), 1873 opr->ndpr_plen, if_name(ifp), 1874 if_name(opr->ndpr_ifp), e); 1875 } 1876 } 1877 } 1878 } else { 1879 /* XXX: can we still set the NDPRF_ONLINK flag? */ 1880 nd6log(LOG_ERR, "failed to delete route: " 1881 "%s/%d on %s (errno = %d)\n", 1882 IN6_PRINT(ip6buf, &sa6.sin6_addr), pr->ndpr_plen, 1883 if_name(ifp), 1884 error); 1885 } 1886 1887 return error; 1888 } 1889 1890 static struct in6_ifaddr * 1891 in6_ifadd(struct nd_prefixctl *prc, int mcast, struct psref *psref) 1892 { 1893 struct ifnet *ifp = prc->ndprc_ifp; 1894 struct ifaddr *ifa; 1895 struct in6_aliasreq ifra; 1896 struct in6_ifaddr *ia, *ib; 1897 int error, plen0; 1898 struct in6_addr mask; 1899 int prefixlen = prc->ndprc_plen; 1900 int updateflags; 1901 int s; 1902 char ip6buf[INET6_ADDRSTRLEN]; 1903 1904 ND6_ASSERT_WLOCK(); 1905 1906 in6_prefixlen2mask(&mask, prefixlen); 1907 1908 /* 1909 * find a link-local address (will be interface ID). 1910 * Is it really mandatory? Theoretically, a global or a site-local 1911 * address can be configured without a link-local address, if we 1912 * have a unique interface identifier... 1913 * 1914 * it is not mandatory to have a link-local address, we can generate 1915 * interface identifier on the fly. we do this because: 1916 * (1) it should be the easiest way to find interface identifier. 1917 * (2) RFC2462 5.4 suggesting the use of the same interface identifier 1918 * for multiple addresses on a single interface, and possible shortcut 1919 * of DAD. we omitted DAD for this reason in the past. 1920 * (3) a user can prevent autoconfiguration of global address 1921 * by removing link-local address by hand (this is partly because we 1922 * don't have other way to control the use of IPv6 on an interface. 1923 * this has been our design choice - cf. NRL's "ifconfig auto"). 1924 * (4) it is easier to manage when an interface has addresses 1925 * with the same interface identifier, than to have multiple addresses 1926 * with different interface identifiers. 1927 */ 1928 s = pserialize_read_enter(); 1929 ifa = (struct ifaddr *)in6ifa_ifpforlinklocal(ifp, 0); /* 0 is OK? */ 1930 if (ifa) 1931 ib = (struct in6_ifaddr *)ifa; 1932 else { 1933 pserialize_read_exit(s); 1934 return NULL; 1935 } 1936 1937 #if 0 /* don't care link local addr state, and always do DAD */ 1938 /* if link-local address is not eligible, do not autoconfigure. */ 1939 if (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_NOTREADY) { 1940 printf("in6_ifadd: link-local address not ready\n"); 1941 return NULL; 1942 } 1943 #endif 1944 1945 /* prefixlen + ifidlen must be equal to 128 */ 1946 plen0 = in6_mask2len(&ib->ia_prefixmask.sin6_addr, NULL); 1947 if (prefixlen != plen0) { 1948 nd6log(LOG_INFO, "wrong prefixlen for %s " 1949 "(prefix=%d ifid=%d)\n", 1950 if_name(ifp), prefixlen, 128 - plen0); 1951 pserialize_read_exit(s); 1952 return NULL; 1953 } 1954 1955 /* make ifaddr */ 1956 1957 memset(&ifra, 0, sizeof(ifra)); 1958 /* 1959 * in6_update_ifa() does not use ifra_name, but we accurately set it 1960 * for safety. 1961 */ 1962 strncpy(ifra.ifra_name, if_name(ifp), sizeof(ifra.ifra_name)); 1963 sockaddr_in6_init(&ifra.ifra_addr, &prc->ndprc_prefix.sin6_addr, 0, 0, 0); 1964 /* prefix */ 1965 ifra.ifra_addr.sin6_addr.s6_addr32[0] &= mask.s6_addr32[0]; 1966 ifra.ifra_addr.sin6_addr.s6_addr32[1] &= mask.s6_addr32[1]; 1967 ifra.ifra_addr.sin6_addr.s6_addr32[2] &= mask.s6_addr32[2]; 1968 ifra.ifra_addr.sin6_addr.s6_addr32[3] &= mask.s6_addr32[3]; 1969 1970 /* interface ID */ 1971 ifra.ifra_addr.sin6_addr.s6_addr32[0] |= 1972 (ib->ia_addr.sin6_addr.s6_addr32[0] & ~mask.s6_addr32[0]); 1973 ifra.ifra_addr.sin6_addr.s6_addr32[1] |= 1974 (ib->ia_addr.sin6_addr.s6_addr32[1] & ~mask.s6_addr32[1]); 1975 ifra.ifra_addr.sin6_addr.s6_addr32[2] |= 1976 (ib->ia_addr.sin6_addr.s6_addr32[2] & ~mask.s6_addr32[2]); 1977 ifra.ifra_addr.sin6_addr.s6_addr32[3] |= 1978 (ib->ia_addr.sin6_addr.s6_addr32[3] & ~mask.s6_addr32[3]); 1979 pserialize_read_exit(s); 1980 1981 /* new prefix mask. */ 1982 sockaddr_in6_init(&ifra.ifra_prefixmask, &mask, 0, 0, 0); 1983 1984 /* lifetimes */ 1985 ifra.ifra_lifetime.ia6t_vltime = prc->ndprc_vltime; 1986 ifra.ifra_lifetime.ia6t_pltime = prc->ndprc_pltime; 1987 1988 /* XXX: scope zone ID? */ 1989 1990 ifra.ifra_flags |= IN6_IFF_AUTOCONF; /* obey autoconf */ 1991 1992 /* 1993 * Make sure that we do not have this address already. This should 1994 * usually not happen, but we can still see this case, e.g., if we 1995 * have manually configured the exact address to be configured. 1996 */ 1997 s = pserialize_read_enter(); 1998 if (in6ifa_ifpwithaddr(ifp, &ifra.ifra_addr.sin6_addr) != NULL) { 1999 /* this should be rare enough to make an explicit log */ 2000 log(LOG_INFO, "in6_ifadd: %s is already configured\n", 2001 IN6_PRINT(ip6buf, &ifra.ifra_addr.sin6_addr)); 2002 pserialize_read_exit(s); 2003 return (NULL); 2004 } 2005 pserialize_read_exit(s); 2006 2007 /* 2008 * Allocate ifaddr structure, link into chain, etc. 2009 * If we are going to create a new address upon receiving a multicasted 2010 * RA, we need to impose a random delay before starting DAD. 2011 * [draft-ietf-ipv6-rfc2462bis-02.txt, Section 5.4.2] 2012 */ 2013 updateflags = 0; 2014 if (mcast) 2015 updateflags |= IN6_IFAUPDATE_DADDELAY; 2016 if ((error = in6_update_ifa(ifp, &ifra, updateflags)) != 0) { 2017 nd6log(LOG_ERR, "failed to make ifaddr %s on %s (errno=%d)\n", 2018 IN6_PRINT(ip6buf, &ifra.ifra_addr.sin6_addr), if_name(ifp), 2019 error); 2020 return (NULL); /* ifaddr must not have been allocated. */ 2021 } 2022 2023 ia = in6ifa_ifpwithaddr_psref(ifp, &ifra.ifra_addr.sin6_addr, psref); 2024 2025 return (ia); /* this is always non-NULL */ 2026 } 2027 2028 int 2029 in6_tmpifadd( 2030 const struct in6_ifaddr *ia0, /* corresponding public address */ 2031 int forcegen, 2032 int dad_delay) 2033 { 2034 struct ifnet *ifp = ia0->ia_ifa.ifa_ifp; 2035 struct in6_ifaddr *newia, *ia; 2036 struct in6_aliasreq ifra; 2037 int i, error; 2038 int trylimit = 3; /* XXX: adhoc value */ 2039 int updateflags; 2040 u_int32_t randid[2]; 2041 u_int32_t vltime0, pltime0; 2042 int s; 2043 2044 ND6_ASSERT_WLOCK(); 2045 2046 memset(&ifra, 0, sizeof(ifra)); 2047 strncpy(ifra.ifra_name, if_name(ifp), sizeof(ifra.ifra_name)); 2048 ifra.ifra_addr = ia0->ia_addr; 2049 /* copy prefix mask */ 2050 ifra.ifra_prefixmask = ia0->ia_prefixmask; 2051 /* clear the old IFID */ 2052 for (i = 0; i < 4; i++) { 2053 ifra.ifra_addr.sin6_addr.s6_addr32[i] &= 2054 ifra.ifra_prefixmask.sin6_addr.s6_addr32[i]; 2055 } 2056 2057 again: 2058 if (in6_get_tmpifid(ifp, (u_int8_t *)randid, 2059 (const u_int8_t *)&ia0->ia_addr.sin6_addr.s6_addr[8], forcegen)) { 2060 nd6log(LOG_NOTICE, "failed to find a good random IFID\n"); 2061 return (EINVAL); 2062 } 2063 ifra.ifra_addr.sin6_addr.s6_addr32[2] |= 2064 (randid[0] & ~(ifra.ifra_prefixmask.sin6_addr.s6_addr32[2])); 2065 ifra.ifra_addr.sin6_addr.s6_addr32[3] |= 2066 (randid[1] & ~(ifra.ifra_prefixmask.sin6_addr.s6_addr32[3])); 2067 2068 /* 2069 * in6_get_tmpifid() quite likely provided a unique interface ID. 2070 * However, we may still have a chance to see collision, because 2071 * there may be a time lag between generation of the ID and generation 2072 * of the address. So, we'll do one more sanity check. 2073 */ 2074 s = pserialize_read_enter(); 2075 IN6_ADDRLIST_READER_FOREACH(ia) { 2076 if (IN6_ARE_ADDR_EQUAL(&ia->ia_addr.sin6_addr, 2077 &ifra.ifra_addr.sin6_addr)) { 2078 pserialize_read_exit(s); 2079 if (trylimit-- == 0) { 2080 /* 2081 * Give up. Something strange should have 2082 * happened. 2083 */ 2084 nd6log(LOG_NOTICE, 2085 "failed to find a unique random IFID\n"); 2086 return (EEXIST); 2087 } 2088 forcegen = 1; 2089 goto again; 2090 } 2091 } 2092 pserialize_read_exit(s); 2093 2094 /* 2095 * The Valid Lifetime is the lower of the Valid Lifetime of the 2096 * public address or TEMP_VALID_LIFETIME. 2097 * The Preferred Lifetime is the lower of the Preferred Lifetime 2098 * of the public address or TEMP_PREFERRED_LIFETIME - 2099 * DESYNC_FACTOR. 2100 */ 2101 if (ia0->ia6_lifetime.ia6t_vltime != ND6_INFINITE_LIFETIME) { 2102 vltime0 = IFA6_IS_INVALID(ia0) ? 0 : 2103 (ia0->ia6_lifetime.ia6t_vltime - 2104 (time_uptime - ia0->ia6_updatetime)); 2105 if (vltime0 > ip6_temp_valid_lifetime) 2106 vltime0 = ip6_temp_valid_lifetime; 2107 } else 2108 vltime0 = ip6_temp_valid_lifetime; 2109 if (ia0->ia6_lifetime.ia6t_pltime != ND6_INFINITE_LIFETIME) { 2110 pltime0 = IFA6_IS_DEPRECATED(ia0) ? 0 : 2111 (ia0->ia6_lifetime.ia6t_pltime - 2112 (time_uptime - ia0->ia6_updatetime)); 2113 if (pltime0 > ip6_temp_preferred_lifetime - ip6_desync_factor){ 2114 pltime0 = ip6_temp_preferred_lifetime - 2115 ip6_desync_factor; 2116 } 2117 } else 2118 pltime0 = ip6_temp_preferred_lifetime - ip6_desync_factor; 2119 ifra.ifra_lifetime.ia6t_vltime = vltime0; 2120 ifra.ifra_lifetime.ia6t_pltime = pltime0; 2121 2122 /* 2123 * A temporary address is created only if this calculated Preferred 2124 * Lifetime is greater than REGEN_ADVANCE time units. 2125 */ 2126 if (ifra.ifra_lifetime.ia6t_pltime <= ip6_temp_regen_advance) 2127 return (0); 2128 2129 /* XXX: scope zone ID? */ 2130 2131 ifra.ifra_flags |= (IN6_IFF_AUTOCONF|IN6_IFF_TEMPORARY); 2132 2133 /* allocate ifaddr structure, link into chain, etc. */ 2134 updateflags = 0; 2135 if (dad_delay) 2136 updateflags |= IN6_IFAUPDATE_DADDELAY; 2137 if ((error = in6_update_ifa(ifp, &ifra, updateflags)) != 0) 2138 return (error); 2139 2140 s = pserialize_read_enter(); 2141 newia = in6ifa_ifpwithaddr(ifp, &ifra.ifra_addr.sin6_addr); 2142 if (newia == NULL) { /* XXX: can it happen? */ 2143 pserialize_read_exit(s); 2144 nd6log(LOG_ERR, 2145 "ifa update succeeded, but we got no ifaddr\n"); 2146 return (EINVAL); /* XXX */ 2147 } 2148 newia->ia6_ndpr = ia0->ia6_ndpr; 2149 newia->ia6_ndpr->ndpr_refcnt++; 2150 pserialize_read_exit(s); 2151 2152 /* 2153 * A newly added address might affect the status of other addresses. 2154 * XXX: when the temporary address is generated with a new public 2155 * address, the onlink check is redundant. However, it would be safe 2156 * to do the check explicitly everywhere a new address is generated, 2157 * and, in fact, we surely need the check when we create a new 2158 * temporary address due to deprecation of an old temporary address. 2159 */ 2160 nd6_pfxlist_onlink_check(); 2161 2162 return (0); 2163 } 2164 2165 static int 2166 in6_init_prefix_ltimes(struct nd_prefix *ndpr) 2167 { 2168 2169 ND6_ASSERT_WLOCK(); 2170 2171 /* check if preferred lifetime > valid lifetime. RFC2462 5.5.3 (c) */ 2172 if (ndpr->ndpr_pltime > ndpr->ndpr_vltime) { 2173 nd6log(LOG_INFO, "preferred lifetime" 2174 "(%d) is greater than valid lifetime(%d)\n", 2175 (u_int)ndpr->ndpr_pltime, (u_int)ndpr->ndpr_vltime); 2176 return (EINVAL); 2177 } 2178 if (ndpr->ndpr_pltime == ND6_INFINITE_LIFETIME) 2179 ndpr->ndpr_preferred = 0; 2180 else 2181 ndpr->ndpr_preferred = time_uptime + ndpr->ndpr_pltime; 2182 if (ndpr->ndpr_vltime == ND6_INFINITE_LIFETIME) 2183 ndpr->ndpr_expire = 0; 2184 else 2185 ndpr->ndpr_expire = time_uptime + ndpr->ndpr_vltime; 2186 2187 return 0; 2188 } 2189 2190 static void 2191 in6_init_address_ltimes(struct nd_prefix *newpr, 2192 struct in6_addrlifetime *lt6) 2193 { 2194 2195 /* Valid lifetime must not be updated unless explicitly specified. */ 2196 /* init ia6t_expire */ 2197 if (lt6->ia6t_vltime == ND6_INFINITE_LIFETIME) 2198 lt6->ia6t_expire = 0; 2199 else { 2200 lt6->ia6t_expire = time_uptime; 2201 lt6->ia6t_expire += lt6->ia6t_vltime; 2202 } 2203 2204 /* init ia6t_preferred */ 2205 if (lt6->ia6t_pltime == ND6_INFINITE_LIFETIME) 2206 lt6->ia6t_preferred = 0; 2207 else { 2208 lt6->ia6t_preferred = time_uptime; 2209 lt6->ia6t_preferred += lt6->ia6t_pltime; 2210 } 2211 } 2212 2213 /* 2214 * Delete all the routing table entries that use the specified gateway. 2215 * XXX: this function causes search through all entries of routing table, so 2216 * it shouldn't be called when acting as a router. 2217 */ 2218 void 2219 nd6_rt_flush(struct in6_addr *gateway, struct ifnet *ifp) 2220 { 2221 2222 #ifndef NET_MPSAFE 2223 KASSERT(mutex_owned(softnet_lock)); 2224 #endif 2225 2226 /* We'll care only link-local addresses */ 2227 if (!IN6_IS_ADDR_LINKLOCAL(gateway)) 2228 return; 2229 2230 rt_delete_matched_entries(AF_INET6, rt6_deleteroute_matcher, gateway); 2231 } 2232 2233 static int 2234 rt6_deleteroute_matcher(struct rtentry *rt, void *arg) 2235 { 2236 struct in6_addr *gate = (struct in6_addr *)arg; 2237 2238 if (rt->rt_gateway == NULL || rt->rt_gateway->sa_family != AF_INET6) 2239 return (0); 2240 2241 if (!IN6_ARE_ADDR_EQUAL(gate, &satosin6(rt->rt_gateway)->sin6_addr)) 2242 return (0); 2243 2244 /* 2245 * Do not delete a static route. 2246 * XXX: this seems to be a bit ad-hoc. Should we consider the 2247 * 'cloned' bit instead? 2248 */ 2249 if ((rt->rt_flags & RTF_STATIC) != 0) 2250 return (0); 2251 2252 /* 2253 * We delete only host route. This means, in particular, we don't 2254 * delete default route. 2255 */ 2256 if ((rt->rt_flags & RTF_HOST) == 0) 2257 return (0); 2258 2259 return 1; 2260 } 2261