1/* $NetBSD: nd6_rtr.c,v 1.82.10.2 2013/07/12 11:18:57 jdc 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 1.82.10.2 2013/07/12 11:18:57 jdc Exp $"); 35 36#include <sys/param.h> 37#include <sys/systm.h> 38#include <sys/malloc.h> 39#include <sys/mbuf.h> 40#include <sys/socket.h> 41#include <sys/sockio.h> 42#include <sys/time.h> 43#include <sys/kernel.h> 44#include <sys/errno.h> 45#include <sys/ioctl.h> 46#include <sys/syslog.h> 47#include <sys/cprng.h> 48 49#include <net/if.h> 50#include <net/if_types.h> 51#include <net/if_dl.h> 52#include <net/route.h> 53#include <net/radix.h> 54 55#include <netinet/in.h> 56#include <netinet6/in6_var.h> 57#include <netinet6/in6_ifattach.h> 58#include <netinet/ip6.h> 59#include <netinet6/ip6_var.h> 60#include <netinet6/nd6.h> 61#include <netinet/icmp6.h> 62#include <netinet6/icmp6_private.h> 63#include <netinet6/scope6_var.h> 64 65#include <net/net_osdep.h> 66 67static int rtpref(struct nd_defrouter *); 68static struct nd_defrouter *defrtrlist_update(struct nd_defrouter *); 69static int prelist_update(struct nd_prefixctl *, struct nd_defrouter *, 70 struct mbuf *, int); 71static struct in6_ifaddr *in6_ifadd(struct nd_prefixctl *, int); 72static struct nd_pfxrouter *pfxrtr_lookup(struct nd_prefix *, 73 struct nd_defrouter *); 74static void pfxrtr_add(struct nd_prefix *, struct nd_defrouter *); 75static void pfxrtr_del(struct nd_pfxrouter *); 76static struct nd_pfxrouter *find_pfxlist_reachable_router 77 (struct nd_prefix *); 78static void defrouter_delreq(struct nd_defrouter *); 79static void nd6_rtmsg(int, struct rtentry *); 80 81static int in6_init_prefix_ltimes(struct nd_prefix *); 82static void in6_init_address_ltimes(struct nd_prefix *, 83 struct in6_addrlifetime *); 84static void purge_detached(struct ifnet *); 85 86static int rt6_deleteroute(struct rtentry *, void *); 87 88extern int nd6_recalc_reachtm_interval; 89 90static struct ifnet *nd6_defifp; 91int nd6_defifindex; 92 93int ip6_use_tempaddr = 0; 94 95int ip6_desync_factor; 96u_int32_t ip6_temp_preferred_lifetime = DEF_TEMP_PREFERRED_LIFETIME; 97u_int32_t ip6_temp_valid_lifetime = DEF_TEMP_VALID_LIFETIME; 98int ip6_temp_regen_advance = TEMPADDR_REGEN_ADVANCE; 99 100int nd6_numroutes = 0; 101 102/* RTPREF_MEDIUM has to be 0! */ 103#define RTPREF_HIGH 1 104#define RTPREF_MEDIUM 0 105#define RTPREF_LOW (-1) 106#define RTPREF_RESERVED (-2) 107#define RTPREF_INVALID (-3) /* internal */ 108 109/* 110 * Receive Router Solicitation Message - just for routers. 111 * Router solicitation/advertisement is mostly managed by a userland program 112 * (rtadvd) so here we have no function like nd6_ra_output(). 113 * 114 * Based on RFC 2461 115 */ 116void 117nd6_rs_input(struct mbuf *m, int off, int icmp6len) 118{ 119 struct ifnet *ifp = m->m_pkthdr.rcvif; 120 struct nd_ifinfo *ndi = ND_IFINFO(ifp); 121 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 122 struct nd_router_solicit *nd_rs; 123 struct in6_addr saddr6 = ip6->ip6_src; 124 char *lladdr = NULL; 125 int lladdrlen = 0; 126 union nd_opts ndopts; 127 128 /* If I'm not a router, ignore it. */ 129 if (nd6_accepts_rtadv(ndi) || !ip6_forwarding) 130 goto freeit; 131 132 /* Sanity checks */ 133 if (ip6->ip6_hlim != 255) { 134 nd6log((LOG_ERR, 135 "nd6_rs_input: invalid hlim (%d) from %s to %s on %s\n", 136 ip6->ip6_hlim, ip6_sprintf(&ip6->ip6_src), 137 ip6_sprintf(&ip6->ip6_dst), if_name(ifp))); 138 goto bad; 139 } 140 141 /* 142 * Don't update the neighbor cache, if src = ::. 143 * This indicates that the src has no IP address assigned yet. 144 */ 145 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) 146 goto freeit; 147 148 IP6_EXTHDR_GET(nd_rs, struct nd_router_solicit *, m, off, icmp6len); 149 if (nd_rs == NULL) { 150 ICMP6_STATINC(ICMP6_STAT_TOOSHORT); 151 return; 152 } 153 154 icmp6len -= sizeof(*nd_rs); 155 nd6_option_init(nd_rs + 1, icmp6len, &ndopts); 156 if (nd6_options(&ndopts) < 0) { 157 nd6log((LOG_INFO, 158 "nd6_rs_input: invalid ND option, ignored\n")); 159 /* nd6_options have incremented stats */ 160 goto freeit; 161 } 162 163 if (ndopts.nd_opts_src_lladdr) { 164 lladdr = (char *)(ndopts.nd_opts_src_lladdr + 1); 165 lladdrlen = ndopts.nd_opts_src_lladdr->nd_opt_len << 3; 166 } 167 168 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) { 169 nd6log((LOG_INFO, 170 "nd6_rs_input: lladdrlen mismatch for %s " 171 "(if %d, RS packet %d)\n", 172 ip6_sprintf(&saddr6), ifp->if_addrlen, lladdrlen - 2)); 173 goto bad; 174 } 175 176 nd6_cache_lladdr(ifp, &saddr6, lladdr, lladdrlen, ND_ROUTER_SOLICIT, 0); 177 178 freeit: 179 m_freem(m); 180 return; 181 182 bad: 183 ICMP6_STATINC(ICMP6_STAT_BADRS); 184 m_freem(m); 185} 186 187/* 188 * Receive Router Advertisement Message. 189 * 190 * Based on RFC 2461 191 * TODO: on-link bit on prefix information 192 * TODO: ND_RA_FLAG_{OTHER,MANAGED} processing 193 */ 194void 195nd6_ra_input(struct mbuf *m, int off, int icmp6len) 196{ 197 struct ifnet *ifp = m->m_pkthdr.rcvif; 198 struct nd_ifinfo *ndi = ND_IFINFO(ifp); 199 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 200 struct nd_router_advert *nd_ra; 201 struct in6_addr saddr6 = ip6->ip6_src; 202#if 0 203 struct in6_addr daddr6 = ip6->ip6_dst; 204 int flags; /* = nd_ra->nd_ra_flags_reserved; */ 205 int is_managed = ((flags & ND_RA_FLAG_MANAGED) != 0); 206 int is_other = ((flags & ND_RA_FLAG_OTHER) != 0); 207#endif 208 int mcast = 0; 209 union nd_opts ndopts; 210 struct nd_defrouter *dr; 211 212 /* 213 * We only accept RAs when 214 * the system-wide variable allows the acceptance, and the 215 * per-interface variable allows RAs on the receiving interface. 216 */ 217 if (!nd6_accepts_rtadv(ndi)) 218 goto freeit; 219 220 if (ip6->ip6_hlim != 255) { 221 nd6log((LOG_ERR, 222 "nd6_ra_input: invalid hlim (%d) from %s to %s on %s\n", 223 ip6->ip6_hlim, ip6_sprintf(&ip6->ip6_src), 224 ip6_sprintf(&ip6->ip6_dst), if_name(ifp))); 225 goto bad; 226 } 227 228 if (!IN6_IS_ADDR_LINKLOCAL(&saddr6)) { 229 nd6log((LOG_ERR, 230 "nd6_ra_input: src %s is not link-local\n", 231 ip6_sprintf(&saddr6))); 232 goto bad; 233 } 234 235 IP6_EXTHDR_GET(nd_ra, struct nd_router_advert *, m, off, icmp6len); 236 if (nd_ra == NULL) { 237 ICMP6_STATINC(ICMP6_STAT_TOOSHORT); 238 return; 239 } 240 241 icmp6len -= sizeof(*nd_ra); 242 nd6_option_init(nd_ra + 1, icmp6len, &ndopts); 243 if (nd6_options(&ndopts) < 0) { 244 nd6log((LOG_INFO, 245 "nd6_ra_input: invalid ND option, ignored\n")); 246 /* nd6_options have incremented stats */ 247 goto freeit; 248 } 249 250 { 251 struct nd_defrouter drtr; 252 u_int32_t advreachable = nd_ra->nd_ra_reachable; 253 254 /* remember if this is a multicasted advertisement */ 255 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) 256 mcast = 1; 257 258 memset(&drtr, 0, sizeof(drtr)); 259 drtr.rtaddr = saddr6; 260 drtr.flags = nd_ra->nd_ra_flags_reserved; 261 drtr.rtlifetime = ntohs(nd_ra->nd_ra_router_lifetime); 262 drtr.expire = time_second + drtr.rtlifetime; 263 drtr.ifp = ifp; 264 /* unspecified or not? (RFC 2461 6.3.4) */ 265 if (advreachable) { 266 NTOHL(advreachable); 267 if (advreachable <= MAX_REACHABLE_TIME && 268 ndi->basereachable != advreachable) { 269 ndi->basereachable = advreachable; 270 ndi->reachable = ND_COMPUTE_RTIME(ndi->basereachable); 271 ndi->recalctm = nd6_recalc_reachtm_interval; /* reset */ 272 } 273 } 274 if (nd_ra->nd_ra_retransmit) 275 ndi->retrans = ntohl(nd_ra->nd_ra_retransmit); 276 if (nd_ra->nd_ra_curhoplimit) 277 ndi->chlim = nd_ra->nd_ra_curhoplimit; 278 dr = defrtrlist_update(&drtr); 279 } 280 281 /* 282 * prefix 283 */ 284 if (ndopts.nd_opts_pi) { 285 struct nd_opt_hdr *pt; 286 struct nd_opt_prefix_info *pi = NULL; 287 struct nd_prefixctl pr; 288 289 for (pt = (struct nd_opt_hdr *)ndopts.nd_opts_pi; 290 pt <= (struct nd_opt_hdr *)ndopts.nd_opts_pi_end; 291 pt = (struct nd_opt_hdr *)((char *)pt + 292 (pt->nd_opt_len << 3))) { 293 if (pt->nd_opt_type != ND_OPT_PREFIX_INFORMATION) 294 continue; 295 pi = (struct nd_opt_prefix_info *)pt; 296 297 if (pi->nd_opt_pi_len != 4) { 298 nd6log((LOG_INFO, 299 "nd6_ra_input: invalid option " 300 "len %d for prefix information option, " 301 "ignored\n", pi->nd_opt_pi_len)); 302 continue; 303 } 304 305 if (128 < pi->nd_opt_pi_prefix_len) { 306 nd6log((LOG_INFO, 307 "nd6_ra_input: invalid prefix " 308 "len %d for prefix information option, " 309 "ignored\n", pi->nd_opt_pi_prefix_len)); 310 continue; 311 } 312 313 if (IN6_IS_ADDR_MULTICAST(&pi->nd_opt_pi_prefix) 314 || IN6_IS_ADDR_LINKLOCAL(&pi->nd_opt_pi_prefix)) { 315 nd6log((LOG_INFO, 316 "nd6_ra_input: invalid prefix " 317 "%s, ignored\n", 318 ip6_sprintf(&pi->nd_opt_pi_prefix))); 319 continue; 320 } 321 322 memset(&pr, 0, sizeof(pr)); 323 sockaddr_in6_init(&pr.ndpr_prefix, 324 &pi->nd_opt_pi_prefix, 0, 0, 0); 325 pr.ndpr_ifp = (struct ifnet *)m->m_pkthdr.rcvif; 326 327 pr.ndpr_raf_onlink = (pi->nd_opt_pi_flags_reserved & 328 ND_OPT_PI_FLAG_ONLINK) ? 1 : 0; 329 pr.ndpr_raf_auto = (pi->nd_opt_pi_flags_reserved & 330 ND_OPT_PI_FLAG_AUTO) ? 1 : 0; 331 pr.ndpr_plen = pi->nd_opt_pi_prefix_len; 332 pr.ndpr_vltime = ntohl(pi->nd_opt_pi_valid_time); 333 pr.ndpr_pltime = ntohl(pi->nd_opt_pi_preferred_time); 334 335 (void)prelist_update(&pr, dr, m, mcast); 336 } 337 } 338 339 /* 340 * MTU 341 */ 342 if (ndopts.nd_opts_mtu && ndopts.nd_opts_mtu->nd_opt_mtu_len == 1) { 343 u_long mtu; 344 u_long maxmtu; 345 346 mtu = ntohl(ndopts.nd_opts_mtu->nd_opt_mtu_mtu); 347 348 /* lower bound */ 349 if (mtu < IPV6_MMTU) { 350 nd6log((LOG_INFO, "nd6_ra_input: bogus mtu option " 351 "mtu=%lu sent from %s, ignoring\n", 352 mtu, ip6_sprintf(&ip6->ip6_src))); 353 goto skip; 354 } 355 356 /* upper bound */ 357 maxmtu = (ndi->maxmtu && ndi->maxmtu < ifp->if_mtu) 358 ? ndi->maxmtu : ifp->if_mtu; 359 if (mtu <= maxmtu) { 360 int change = (ndi->linkmtu != mtu); 361 362 ndi->linkmtu = mtu; 363 if (change) /* in6_maxmtu may change */ 364 in6_setmaxmtu(); 365 } else { 366 nd6log((LOG_INFO, "nd6_ra_input: bogus mtu " 367 "mtu=%lu sent from %s; " 368 "exceeds maxmtu %lu, ignoring\n", 369 mtu, ip6_sprintf(&ip6->ip6_src), maxmtu)); 370 } 371 } 372 373 skip: 374 375 /* 376 * Source link layer address 377 */ 378 { 379 char *lladdr = NULL; 380 int lladdrlen = 0; 381 382 if (ndopts.nd_opts_src_lladdr) { 383 lladdr = (char *)(ndopts.nd_opts_src_lladdr + 1); 384 lladdrlen = ndopts.nd_opts_src_lladdr->nd_opt_len << 3; 385 } 386 387 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) { 388 nd6log((LOG_INFO, 389 "nd6_ra_input: lladdrlen mismatch for %s " 390 "(if %d, RA packet %d)\n", ip6_sprintf(&saddr6), 391 ifp->if_addrlen, lladdrlen - 2)); 392 goto bad; 393 } 394 395 nd6_cache_lladdr(ifp, &saddr6, lladdr, lladdrlen, ND_ROUTER_ADVERT, 0); 396 397 /* 398 * Installing a link-layer address might change the state of the 399 * router's neighbor cache, which might also affect our on-link 400 * detection of adveritsed prefixes. 401 */ 402 pfxlist_onlink_check(); 403 } 404 405 freeit: 406 m_freem(m); 407 return; 408 409 bad: 410 ICMP6_STATINC(ICMP6_STAT_BADRA); 411 m_freem(m); 412} 413 414/* 415 * default router list processing sub routines 416 */ 417 418/* tell the change to user processes watching the routing socket. */ 419static void 420nd6_rtmsg(int cmd, struct rtentry *rt) 421{ 422 struct rt_addrinfo info; 423 424 memset((void *)&info, 0, sizeof(info)); 425 info.rti_info[RTAX_DST] = rt_getkey(rt); 426 info.rti_info[RTAX_GATEWAY] = rt->rt_gateway; 427 info.rti_info[RTAX_NETMASK] = rt_mask(rt); 428 if (rt->rt_ifp) { 429 info.rti_info[RTAX_IFP] = rt->rt_ifp->if_dl->ifa_addr; 430 info.rti_info[RTAX_IFA] = rt->rt_ifa->ifa_addr; 431 } 432 433 rt_missmsg(cmd, &info, rt->rt_flags, 0); 434} 435 436void 437defrouter_addreq(struct nd_defrouter *new) 438{ 439 union { 440 struct sockaddr_in6 sin6; 441 struct sockaddr sa; 442 } def, mask, gate; 443 struct rtentry *newrt = NULL; 444 int s; 445 int error; 446 447 memset(&def, 0, sizeof(def)); 448 memset(&mask, 0, sizeof(mask)); 449 memset(&gate, 0,sizeof(gate)); /* for safety */ 450 451 def.sin6.sin6_len = mask.sin6.sin6_len = gate.sin6.sin6_len = 452 sizeof(struct sockaddr_in6); 453 def.sin6.sin6_family = mask.sin6.sin6_family = gate.sin6.sin6_family = AF_INET6; 454 gate.sin6.sin6_addr = new->rtaddr; 455#ifndef SCOPEDROUTING 456 gate.sin6.sin6_scope_id = 0; /* XXX */ 457#endif 458 459 s = splsoftnet(); 460 error = rtrequest(RTM_ADD, &def.sa, &gate.sa, &mask.sa, 461 RTF_GATEWAY, &newrt); 462 if (newrt) { 463 nd6_rtmsg(RTM_ADD, newrt); /* tell user process */ 464 newrt->rt_refcnt--; 465 nd6_numroutes++; 466 } 467 if (error == 0) 468 new->installed = 1; 469 splx(s); 470 return; 471} 472 473struct nd_defrouter * 474defrouter_lookup(const struct in6_addr *addr, struct ifnet *ifp) 475{ 476 struct nd_defrouter *dr; 477 478 TAILQ_FOREACH(dr, &nd_defrouter, dr_entry) { 479 if (dr->ifp == ifp && IN6_ARE_ADDR_EQUAL(addr, &dr->rtaddr)) 480 break; 481 } 482 483 return dr; /* search failed */ 484} 485 486void 487defrtrlist_del(struct nd_defrouter *dr) 488{ 489 struct nd_ifinfo *ndi = ND_IFINFO(dr->ifp); 490 struct nd_defrouter *deldr = NULL; 491 struct nd_prefix *pr; 492 struct in6_ifextra *ext = dr->ifp->if_afdata[AF_INET6]; 493 494 /* 495 * Flush all the routing table entries that use the router 496 * as a next hop. 497 */ 498 /* XXX: better condition? */ 499 if (!ip6_forwarding && nd6_accepts_rtadv(ndi)) 500 rt6_flush(&dr->rtaddr, dr->ifp); 501 502 if (dr->installed) { 503 deldr = dr; 504 defrouter_delreq(dr); 505 } 506 TAILQ_REMOVE(&nd_defrouter, dr, dr_entry); 507 508 /* 509 * Also delete all the pointers to the router in each prefix lists. 510 */ 511 LIST_FOREACH(pr, &nd_prefix, ndpr_entry) { 512 struct nd_pfxrouter *pfxrtr; 513 if ((pfxrtr = pfxrtr_lookup(pr, dr)) != NULL) 514 pfxrtr_del(pfxrtr); 515 } 516 pfxlist_onlink_check(); 517 518 /* 519 * If the router is the primary one, choose a new one. 520 * Note that defrouter_select() will remove the current gateway 521 * from the routing table. 522 */ 523 if (deldr) 524 defrouter_select(); 525 526 ext->ndefrouters--; 527 if (ext->ndefrouters < 0) { 528 log(LOG_WARNING, "defrtrlist_del: negative count on %s\n", 529 dr->ifp->if_xname); 530 } 531 532 free(dr, M_IP6NDP); 533} 534 535/* 536 * Remove the default route for a given router. 537 * This is just a subroutine function for defrouter_select(), and should 538 * not be called from anywhere else. 539 */ 540static void 541defrouter_delreq(struct nd_defrouter *dr) 542{ 543 union { 544 struct sockaddr_in6 sin6; 545 struct sockaddr sa; 546 } def, mask, gw; 547 struct rtentry *oldrt = NULL; 548 549#ifdef DIAGNOSTIC 550 if (dr == NULL) 551 panic("dr == NULL in defrouter_delreq"); 552#endif 553 554 memset(&def, 0, sizeof(def)); 555 memset(&mask, 0, sizeof(mask)); 556 memset(&gw, 0, sizeof(gw)); /* for safety */ 557 558 def.sin6.sin6_len = mask.sin6.sin6_len = gw.sin6.sin6_len = 559 sizeof(struct sockaddr_in6); 560 def.sin6.sin6_family = mask.sin6.sin6_family = gw.sin6.sin6_family = AF_INET6; 561 gw.sin6.sin6_addr = dr->rtaddr; 562#ifndef SCOPEDROUTING 563 gw.sin6.sin6_scope_id = 0; /* XXX */ 564#endif 565 566 rtrequest(RTM_DELETE, &def.sa, &gw.sa, &mask.sa, RTF_GATEWAY, &oldrt); 567 if (oldrt) { 568 nd6_rtmsg(RTM_DELETE, oldrt); 569 if (oldrt->rt_refcnt <= 0) { 570 /* 571 * XXX: borrowed from the RTM_DELETE case of 572 * rtrequest(). 573 */ 574 oldrt->rt_refcnt++; 575 rtfree(oldrt); 576 nd6_numroutes--; 577 } 578 } 579 580 dr->installed = 0; 581} 582 583/* 584 * remove all default routes from default router list 585 */ 586void 587defrouter_reset(void) 588{ 589 struct nd_defrouter *dr; 590 591 for (dr = TAILQ_FIRST(&nd_defrouter); dr; 592 dr = TAILQ_NEXT(dr, dr_entry)) 593 defrouter_delreq(dr); 594 595 /* 596 * XXX should we also nuke any default routers in the kernel, by 597 * going through them by rtalloc1()? 598 */ 599} 600 601/* 602 * Default Router Selection according to Section 6.3.6 of RFC 2461 and 603 * draft-ietf-ipngwg-router-selection: 604 * 1) Routers that are reachable or probably reachable should be preferred. 605 * If we have more than one (probably) reachable router, prefer ones 606 * with the highest router preference. 607 * 2) When no routers on the list are known to be reachable or 608 * probably reachable, routers SHOULD be selected in a round-robin 609 * fashion, regardless of router preference values. 610 * 3) If the Default Router List is empty, assume that all 611 * destinations are on-link. 612 * 613 * We assume nd_defrouter is sorted by router preference value. 614 * Since the code below covers both with and without router preference cases, 615 * we do not need to classify the cases by ifdef. 616 * 617 * At this moment, we do not try to install more than one default router, 618 * even when the multipath routing is available, because we're not sure about 619 * the benefits for stub hosts comparing to the risk of making the code 620 * complicated and the possibility of introducing bugs. 621 */ 622void 623defrouter_select(void) 624{ 625 struct nd_ifinfo *ndi; 626 int s = splsoftnet(); 627 struct nd_defrouter *dr, *selected_dr = NULL, *installed_dr = NULL; 628 struct rtentry *rt = NULL; 629 struct llinfo_nd6 *ln = NULL; 630 631 /* 632 * This function should be called only when acting as an autoconfigured 633 * host. Although the remaining part of this function is not effective 634 * if the node is not an autoconfigured host, we explicitly exclude 635 * such cases here for safety. 636 */ 637 if (ip6_forwarding) { 638 nd6log((LOG_WARNING, 639 "defrouter_select: called unexpectedly (forwarding=%d, " 640 "accept_rtadv=%d)\n", ip6_forwarding, ip6_accept_rtadv)); 641 splx(s); 642 return; 643 } 644 645 /* 646 * Let's handle easy case (3) first: 647 * If default router list is empty, there's nothing to be done. 648 */ 649 if (!TAILQ_FIRST(&nd_defrouter)) { 650 splx(s); 651 return; 652 } 653 654 /* 655 * Search for a (probably) reachable router from the list. 656 * We just pick up the first reachable one (if any), assuming that 657 * the ordering rule of the list described in defrtrlist_update(). 658 */ 659 for (dr = TAILQ_FIRST(&nd_defrouter); dr; 660 dr = TAILQ_NEXT(dr, dr_entry)) { 661 ndi = ND_IFINFO(dr->ifp); 662 if (nd6_accepts_rtadv(ndi)) 663 continue; 664 665 if (selected_dr == NULL && 666 (rt = nd6_lookup(&dr->rtaddr, 0, dr->ifp)) != NULL && 667 (ln = (struct llinfo_nd6 *)rt->rt_llinfo) != NULL && 668 ND6_IS_LLINFO_PROBREACH(ln)) { 669 selected_dr = dr; 670 } 671 672 if (dr->installed && !installed_dr) 673 installed_dr = dr; 674 else if (dr->installed && installed_dr) { 675 /* this should not happen. warn for diagnosis. */ 676 log(LOG_ERR, "defrouter_select: more than one router" 677 " is installed\n"); 678 } 679 } 680 /* 681 * If none of the default routers was found to be reachable, 682 * round-robin the list regardless of preference. 683 * Otherwise, if we have an installed router, check if the selected 684 * (reachable) router should really be preferred to the installed one. 685 * We only prefer the new router when the old one is not reachable 686 * or when the new one has a really higher preference value. 687 */ 688 if (selected_dr == NULL) { 689 if (installed_dr == NULL || !TAILQ_NEXT(installed_dr, dr_entry)) 690 selected_dr = TAILQ_FIRST(&nd_defrouter); 691 else 692 selected_dr = TAILQ_NEXT(installed_dr, dr_entry); 693 } else if (installed_dr && 694 (rt = nd6_lookup(&installed_dr->rtaddr, 0, installed_dr->ifp)) && 695 (ln = (struct llinfo_nd6 *)rt->rt_llinfo) && 696 ND6_IS_LLINFO_PROBREACH(ln) && 697 rtpref(selected_dr) <= rtpref(installed_dr)) { 698 selected_dr = installed_dr; 699 } 700 701 /* 702 * If the selected router is different than the installed one, 703 * remove the installed router and install the selected one. 704 * Note that the selected router is never NULL here. 705 */ 706 if (installed_dr != selected_dr) { 707 if (installed_dr) 708 defrouter_delreq(installed_dr); 709 defrouter_addreq(selected_dr); 710 } 711 712 splx(s); 713 return; 714} 715 716/* 717 * for default router selection 718 * regards router-preference field as a 2-bit signed integer 719 */ 720static int 721rtpref(struct nd_defrouter *dr) 722{ 723 switch (dr->flags & ND_RA_FLAG_RTPREF_MASK) { 724 case ND_RA_FLAG_RTPREF_HIGH: 725 return (RTPREF_HIGH); 726 case ND_RA_FLAG_RTPREF_MEDIUM: 727 case ND_RA_FLAG_RTPREF_RSV: 728 return (RTPREF_MEDIUM); 729 case ND_RA_FLAG_RTPREF_LOW: 730 return (RTPREF_LOW); 731 default: 732 /* 733 * This case should never happen. If it did, it would mean a 734 * serious bug of kernel internal. We thus always bark here. 735 * Or, can we even panic? 736 */ 737 log(LOG_ERR, "rtpref: impossible RA flag %x\n", dr->flags); 738 return (RTPREF_INVALID); 739 } 740 /* NOTREACHED */ 741} 742 743static struct nd_defrouter * 744defrtrlist_update(struct nd_defrouter *new) 745{ 746 struct nd_defrouter *dr, *n; 747 struct in6_ifextra *ext = new->ifp->if_afdata[AF_INET6]; 748 int s = splsoftnet(); 749 750 if ((dr = defrouter_lookup(&new->rtaddr, new->ifp)) != NULL) { 751 /* entry exists */ 752 if (new->rtlifetime == 0) { 753 defrtrlist_del(dr); 754 dr = NULL; 755 } else { 756 int oldpref = rtpref(dr); 757 758 /* override */ 759 dr->flags = new->flags; /* xxx flag check */ 760 dr->rtlifetime = new->rtlifetime; 761 dr->expire = new->expire; 762 763 /* 764 * If the preference does not change, there's no need 765 * to sort the entries. 766 */ 767 if (rtpref(new) == oldpref) { 768 splx(s); 769 return (dr); 770 } 771 772 /* 773 * preferred router may be changed, so relocate 774 * this router. 775 * XXX: calling TAILQ_REMOVE directly is a bad manner. 776 * However, since defrtrlist_del() has many side 777 * effects, we intentionally do so here. 778 * defrouter_select() below will handle routing 779 * changes later. 780 */ 781 TAILQ_REMOVE(&nd_defrouter, dr, dr_entry); 782 n = dr; 783 goto insert; 784 } 785 splx(s); 786 return (dr); 787 } 788 789 if (ip6_maxifdefrouters >= 0 && 790 ext->ndefrouters >= ip6_maxifdefrouters) { 791 splx(s); 792 return (NULL); 793 } 794 795 /* entry does not exist */ 796 if (new->rtlifetime == 0) { 797 splx(s); 798 return (NULL); 799 } 800 801 if (ip6_rtadv_maxroutes <= nd6_numroutes) { 802 ICMP6_STATINC(ICMP6_STAT_DROPPED_RAROUTE); 803 splx(s); 804 return (NULL); 805 } 806 807 n = (struct nd_defrouter *)malloc(sizeof(*n), M_IP6NDP, M_NOWAIT); 808 if (n == NULL) { 809 splx(s); 810 return (NULL); 811 } 812 memset(n, 0, sizeof(*n)); 813 *n = *new; 814 815insert: 816 /* 817 * Insert the new router in the Default Router List; 818 * The Default Router List should be in the descending order 819 * of router-preferece. Routers with the same preference are 820 * sorted in the arriving time order. 821 */ 822 823 /* insert at the end of the group */ 824 for (dr = TAILQ_FIRST(&nd_defrouter); dr; 825 dr = TAILQ_NEXT(dr, dr_entry)) { 826 if (rtpref(n) > rtpref(dr)) 827 break; 828 } 829 if (dr) 830 TAILQ_INSERT_BEFORE(dr, n, dr_entry); 831 else 832 TAILQ_INSERT_TAIL(&nd_defrouter, n, dr_entry); 833 834 defrouter_select(); 835 836 ext->ndefrouters++; 837 838 splx(s); 839 840 return (n); 841} 842 843static struct nd_pfxrouter * 844pfxrtr_lookup(struct nd_prefix *pr, struct nd_defrouter *dr) 845{ 846 struct nd_pfxrouter *search; 847 848 LIST_FOREACH(search, &pr->ndpr_advrtrs, pfr_entry) { 849 if (search->router == dr) 850 break; 851 } 852 853 return (search); 854} 855 856static void 857pfxrtr_add(struct nd_prefix *pr, struct nd_defrouter *dr) 858{ 859 struct nd_pfxrouter *new; 860 861 new = malloc(sizeof(*new), M_IP6NDP, M_NOWAIT|M_ZERO); 862 if (new == NULL) 863 return; 864 new->router = dr; 865 866 LIST_INSERT_HEAD(&pr->ndpr_advrtrs, new, pfr_entry); 867 868 pfxlist_onlink_check(); 869} 870 871static void 872pfxrtr_del(struct nd_pfxrouter *pfr) 873{ 874 LIST_REMOVE(pfr, pfr_entry); 875 free(pfr, M_IP6NDP); 876} 877 878struct nd_prefix * 879nd6_prefix_lookup(struct nd_prefixctl *key) 880{ 881 struct nd_prefix *search; 882 883 LIST_FOREACH(search, &nd_prefix, ndpr_entry) { 884 if (key->ndpr_ifp == search->ndpr_ifp && 885 key->ndpr_plen == search->ndpr_plen && 886 in6_are_prefix_equal(&key->ndpr_prefix.sin6_addr, 887 &search->ndpr_prefix.sin6_addr, key->ndpr_plen)) { 888 break; 889 } 890 } 891 892 return (search); 893} 894 895static void 896purge_detached(struct ifnet *ifp) 897{ 898 struct nd_prefix *pr, *pr_next; 899 struct in6_ifaddr *ia; 900 struct ifaddr *ifa, *ifa_next; 901 902 for (pr = nd_prefix.lh_first; pr; pr = pr_next) { 903 pr_next = pr->ndpr_next; 904 905 /* 906 * This function is called when we need to make more room for 907 * new prefixes rather than keeping old, possibly stale ones. 908 * Detached prefixes would be a good candidate; if all routers 909 * that advertised the prefix expired, the prefix is also 910 * probably stale. 911 */ 912 if (pr->ndpr_ifp != ifp || 913 IN6_IS_ADDR_LINKLOCAL(&pr->ndpr_prefix.sin6_addr) || 914 ((pr->ndpr_stateflags & NDPRF_DETACHED) == 0 && 915 !LIST_EMPTY(&pr->ndpr_advrtrs))) 916 continue; 917 918 for (ifa = ifp->if_addrlist.tqh_first; ifa; ifa = ifa_next) { 919 ifa_next = ifa->ifa_list.tqe_next; 920 if (ifa->ifa_addr->sa_family != AF_INET6) 921 continue; 922 ia = (struct in6_ifaddr *)ifa; 923 if ((ia->ia6_flags & IN6_IFF_AUTOCONF) == 924 IN6_IFF_AUTOCONF && ia->ia6_ndpr == pr) { 925 in6_purgeaddr(ifa); 926 } 927 } 928 if (pr->ndpr_refcnt == 0) 929 prelist_remove(pr); 930 } 931} 932 933int 934nd6_prelist_add(struct nd_prefixctl *pr, struct nd_defrouter *dr, 935 struct nd_prefix **newp) 936{ 937 struct nd_prefix *new = NULL; 938 int i, s; 939 int error; 940 struct in6_ifextra *ext = pr->ndpr_ifp->if_afdata[AF_INET6]; 941 942 if (ip6_maxifprefixes >= 0) { 943 if (ext->nprefixes >= ip6_maxifprefixes / 2) 944 purge_detached(pr->ndpr_ifp); 945 if (ext->nprefixes >= ip6_maxifprefixes) 946 return ENOMEM; 947 } 948 949 error = 0; 950 new = malloc(sizeof(*new), M_IP6NDP, M_NOWAIT|M_ZERO); 951 if (new == NULL) 952 return ENOMEM; 953 new->ndpr_ifp = pr->ndpr_ifp; 954 new->ndpr_prefix = pr->ndpr_prefix; 955 new->ndpr_plen = pr->ndpr_plen; 956 new->ndpr_vltime = pr->ndpr_vltime; 957 new->ndpr_pltime = pr->ndpr_pltime; 958 new->ndpr_flags = pr->ndpr_flags; 959 if ((error = in6_init_prefix_ltimes(new)) != 0) { 960 free(new, M_IP6NDP); 961 return(error); 962 } 963 new->ndpr_lastupdate = time_second; 964 if (newp != NULL) 965 *newp = new; 966 967 /* initialization */ 968 LIST_INIT(&new->ndpr_advrtrs); 969 in6_prefixlen2mask(&new->ndpr_mask, new->ndpr_plen); 970 /* make prefix in the canonical form */ 971 for (i = 0; i < 4; i++) 972 new->ndpr_prefix.sin6_addr.s6_addr32[i] &= 973 new->ndpr_mask.s6_addr32[i]; 974 975 s = splsoftnet(); 976 /* link ndpr_entry to nd_prefix list */ 977 LIST_INSERT_HEAD(&nd_prefix, new, ndpr_entry); 978 splx(s); 979 980 /* ND_OPT_PI_FLAG_ONLINK processing */ 981 if (new->ndpr_raf_onlink) { 982 int e; 983 984 if ((e = nd6_prefix_onlink(new)) != 0) { 985 nd6log((LOG_ERR, "nd6_prelist_add: failed to make " 986 "the prefix %s/%d on-link on %s (errno=%d)\n", 987 ip6_sprintf(&pr->ndpr_prefix.sin6_addr), 988 pr->ndpr_plen, if_name(pr->ndpr_ifp), e)); 989 /* proceed anyway. XXX: is it correct? */ 990 } 991 } 992 993 if (dr) 994 pfxrtr_add(new, dr); 995 ext->nprefixes++; 996 997 return 0; 998} 999 1000void 1001prelist_remove(struct nd_prefix *pr) 1002{ 1003 struct nd_pfxrouter *pfr, *next; 1004 int e, s; 1005 struct in6_ifextra *ext = pr->ndpr_ifp->if_afdata[AF_INET6]; 1006 1007 /* make sure to invalidate the prefix until it is really freed. */ 1008 pr->ndpr_vltime = 0; 1009 pr->ndpr_pltime = 0; 1010#if 0 1011 /* 1012 * Though these flags are now meaningless, we'd rather keep the value 1013 * not to confuse users when executing "ndp -p". 1014 */ 1015 pr->ndpr_raf_onlink = 0; 1016 pr->ndpr_raf_auto = 0; 1017#endif 1018 if ((pr->ndpr_stateflags & NDPRF_ONLINK) != 0 && 1019 (e = nd6_prefix_offlink(pr)) != 0) { 1020 nd6log((LOG_ERR, "prelist_remove: failed to make %s/%d offlink " 1021 "on %s, errno=%d\n", 1022 ip6_sprintf(&pr->ndpr_prefix.sin6_addr), 1023 pr->ndpr_plen, if_name(pr->ndpr_ifp), e)); 1024 /* what should we do? */ 1025 } 1026 1027 if (pr->ndpr_refcnt > 0) 1028 return; /* notice here? */ 1029 1030 s = splsoftnet(); 1031 /* unlink ndpr_entry from nd_prefix list */ 1032 LIST_REMOVE(pr, ndpr_entry); 1033 1034 /* free list of routers that adversed the prefix */ 1035 for (pfr = LIST_FIRST(&pr->ndpr_advrtrs); pfr != NULL; pfr = next) { 1036 next = LIST_NEXT(pfr, pfr_entry); 1037 1038 free(pfr, M_IP6NDP); 1039 } 1040 1041 if (ext) { 1042 ext->nprefixes--; 1043 if (ext->nprefixes < 0) { 1044 log(LOG_WARNING, "prelist_remove: negative count on " 1045 "%s\n", pr->ndpr_ifp->if_xname); 1046 } 1047 } 1048 splx(s); 1049 1050 free(pr, M_IP6NDP); 1051 1052 pfxlist_onlink_check(); 1053} 1054 1055static int 1056prelist_update(struct nd_prefixctl *new, 1057 struct nd_defrouter *dr, /* may be NULL */ 1058 struct mbuf *m, 1059 int mcast) 1060{ 1061 struct in6_ifaddr *ia6 = NULL, *ia6_match = NULL; 1062 struct ifaddr *ifa; 1063 struct ifnet *ifp = new->ndpr_ifp; 1064 struct nd_prefix *pr; 1065 int s = splsoftnet(); 1066 int error = 0; 1067 int newprefix = 0; 1068 int auth; 1069 struct in6_addrlifetime lt6_tmp; 1070 1071 auth = 0; 1072 if (m) { 1073 /* 1074 * Authenticity for NA consists authentication for 1075 * both IP header and IP datagrams, doesn't it ? 1076 */ 1077#if defined(M_AUTHIPHDR) && defined(M_AUTHIPDGM) 1078 auth = (m->m_flags & M_AUTHIPHDR 1079 && m->m_flags & M_AUTHIPDGM) ? 1 : 0; 1080#endif 1081 } 1082 1083 if ((pr = nd6_prefix_lookup(new)) != NULL) { 1084 /* 1085 * nd6_prefix_lookup() ensures that pr and new have the same 1086 * prefix on a same interface. 1087 */ 1088 1089 /* 1090 * Update prefix information. Note that the on-link (L) bit 1091 * and the autonomous (A) bit should NOT be changed from 1 1092 * to 0. 1093 */ 1094 if (new->ndpr_raf_onlink == 1) 1095 pr->ndpr_raf_onlink = 1; 1096 if (new->ndpr_raf_auto == 1) 1097 pr->ndpr_raf_auto = 1; 1098 if (new->ndpr_raf_onlink) { 1099 pr->ndpr_vltime = new->ndpr_vltime; 1100 pr->ndpr_pltime = new->ndpr_pltime; 1101 (void)in6_init_prefix_ltimes(pr); /* XXX error case? */ 1102 pr->ndpr_lastupdate = time_second; 1103 } 1104 1105 if (new->ndpr_raf_onlink && 1106 (pr->ndpr_stateflags & NDPRF_ONLINK) == 0) { 1107 int e; 1108 1109 if ((e = nd6_prefix_onlink(pr)) != 0) { 1110 nd6log((LOG_ERR, 1111 "prelist_update: failed to make " 1112 "the prefix %s/%d on-link on %s " 1113 "(errno=%d)\n", 1114 ip6_sprintf(&pr->ndpr_prefix.sin6_addr), 1115 pr->ndpr_plen, if_name(pr->ndpr_ifp), e)); 1116 /* proceed anyway. XXX: is it correct? */ 1117 } 1118 } 1119 1120 if (dr && pfxrtr_lookup(pr, dr) == NULL) 1121 pfxrtr_add(pr, dr); 1122 } else { 1123 struct nd_prefix *newpr = NULL; 1124 1125 newprefix = 1; 1126 1127 if (new->ndpr_vltime == 0) 1128 goto end; 1129 if (new->ndpr_raf_onlink == 0 && new->ndpr_raf_auto == 0) 1130 goto end; 1131 1132 if (ip6_rtadv_maxroutes <= nd6_numroutes) { 1133 ICMP6_STATINC(ICMP6_STAT_DROPPED_RAROUTE); 1134 goto end; 1135 } 1136 1137 error = nd6_prelist_add(new, dr, &newpr); 1138 if (error != 0 || newpr == NULL) { 1139 nd6log((LOG_NOTICE, "prelist_update: " 1140 "nd6_prelist_add failed for %s/%d on %s " 1141 "errno=%d, returnpr=%p\n", 1142 ip6_sprintf(&new->ndpr_prefix.sin6_addr), 1143 new->ndpr_plen, if_name(new->ndpr_ifp), 1144 error, newpr)); 1145 goto end; /* we should just give up in this case. */ 1146 } 1147 1148 /* 1149 * XXX: from the ND point of view, we can ignore a prefix 1150 * with the on-link bit being zero. However, we need a 1151 * prefix structure for references from autoconfigured 1152 * addresses. Thus, we explicitly make sure that the prefix 1153 * itself expires now. 1154 */ 1155 if (newpr->ndpr_raf_onlink == 0) { 1156 newpr->ndpr_vltime = 0; 1157 newpr->ndpr_pltime = 0; 1158 in6_init_prefix_ltimes(newpr); 1159 } 1160 1161 pr = newpr; 1162 } 1163 1164 /* 1165 * Address autoconfiguration based on Section 5.5.3 of RFC 2462. 1166 * Note that pr must be non NULL at this point. 1167 */ 1168 1169 /* 5.5.3 (a). Ignore the prefix without the A bit set. */ 1170 if (!new->ndpr_raf_auto) 1171 goto end; 1172 1173 /* 1174 * 5.5.3 (b). the link-local prefix should have been ignored in 1175 * nd6_ra_input. 1176 */ 1177 1178 /* 5.5.3 (c). Consistency check on lifetimes: pltime <= vltime. */ 1179 if (new->ndpr_pltime > new->ndpr_vltime) { 1180 error = EINVAL; /* XXX: won't be used */ 1181 goto end; 1182 } 1183 1184 /* 1185 * 5.5.3 (d). If the prefix advertised is not equal to the prefix of 1186 * an address configured by stateless autoconfiguration already in the 1187 * list of addresses associated with the interface, and the Valid 1188 * Lifetime is not 0, form an address. We first check if we have 1189 * a matching prefix. 1190 * Note: we apply a clarification in rfc2462bis-02 here. We only 1191 * consider autoconfigured addresses while RFC2462 simply said 1192 * "address". 1193 */ 1194 IFADDR_FOREACH(ifa, ifp) { 1195 struct in6_ifaddr *ifa6; 1196 u_int32_t remaininglifetime; 1197 1198 if (ifa->ifa_addr->sa_family != AF_INET6) 1199 continue; 1200 1201 ifa6 = (struct in6_ifaddr *)ifa; 1202 1203 /* 1204 * We only consider autoconfigured addresses as per rfc2462bis. 1205 */ 1206 if (!(ifa6->ia6_flags & IN6_IFF_AUTOCONF)) 1207 continue; 1208 1209 /* 1210 * Spec is not clear here, but I believe we should concentrate 1211 * on unicast (i.e. not anycast) addresses. 1212 * XXX: other ia6_flags? detached or duplicated? 1213 */ 1214 if ((ifa6->ia6_flags & IN6_IFF_ANYCAST) != 0) 1215 continue; 1216 1217 /* 1218 * Ignore the address if it is not associated with a prefix 1219 * or is associated with a prefix that is different from this 1220 * one. (pr is never NULL here) 1221 */ 1222 if (ifa6->ia6_ndpr != pr) 1223 continue; 1224 1225 if (ia6_match == NULL) /* remember the first one */ 1226 ia6_match = ifa6; 1227 1228 /* 1229 * An already autoconfigured address matched. Now that we 1230 * are sure there is at least one matched address, we can 1231 * proceed to 5.5.3. (e): update the lifetimes according to the 1232 * "two hours" rule and the privacy extension. 1233 * We apply some clarifications in rfc2462bis: 1234 * - use remaininglifetime instead of storedlifetime as a 1235 * variable name 1236 * - remove the dead code in the "two-hour" rule 1237 */ 1238#define TWOHOUR (120*60) 1239 lt6_tmp = ifa6->ia6_lifetime; 1240 if (lt6_tmp.ia6t_vltime == ND6_INFINITE_LIFETIME) 1241 remaininglifetime = ND6_INFINITE_LIFETIME; 1242 else if (time_second - ifa6->ia6_updatetime > 1243 lt6_tmp.ia6t_vltime) { 1244 /* 1245 * The case of "invalid" address. We should usually 1246 * not see this case. 1247 */ 1248 remaininglifetime = 0; 1249 } else 1250 remaininglifetime = lt6_tmp.ia6t_vltime - 1251 (time_second - ifa6->ia6_updatetime); 1252 1253 /* when not updating, keep the current stored lifetime. */ 1254 lt6_tmp.ia6t_vltime = remaininglifetime; 1255 1256 if (TWOHOUR < new->ndpr_vltime || 1257 remaininglifetime < new->ndpr_vltime) { 1258 lt6_tmp.ia6t_vltime = new->ndpr_vltime; 1259 } else if (remaininglifetime <= TWOHOUR) { 1260 if (auth) 1261 lt6_tmp.ia6t_vltime = new->ndpr_vltime; 1262 } else { 1263 /* 1264 * new->ndpr_vltime <= TWOHOUR && 1265 * TWOHOUR < remaininglifetime 1266 */ 1267 lt6_tmp.ia6t_vltime = TWOHOUR; 1268 } 1269 1270 /* The 2 hour rule is not imposed for preferred lifetime. */ 1271 lt6_tmp.ia6t_pltime = new->ndpr_pltime; 1272 1273 in6_init_address_ltimes(pr, <6_tmp); 1274 1275 /* 1276 * We need to treat lifetimes for temporary addresses 1277 * differently, according to 1278 * draft-ietf-ipv6-privacy-addrs-v2-01.txt 3.3 (1); 1279 * we only update the lifetimes when they are in the maximum 1280 * intervals. 1281 */ 1282 if ((ifa6->ia6_flags & IN6_IFF_TEMPORARY) != 0) { 1283 u_int32_t maxvltime, maxpltime; 1284 1285 if (ip6_temp_valid_lifetime > 1286 (u_int32_t)((time_second - ifa6->ia6_createtime) + 1287 ip6_desync_factor)) { 1288 maxvltime = ip6_temp_valid_lifetime - 1289 (time_second - ifa6->ia6_createtime) - 1290 ip6_desync_factor; 1291 } else 1292 maxvltime = 0; 1293 if (ip6_temp_preferred_lifetime > 1294 (u_int32_t)((time_second - ifa6->ia6_createtime) + 1295 ip6_desync_factor)) { 1296 maxpltime = ip6_temp_preferred_lifetime - 1297 (time_second - ifa6->ia6_createtime) - 1298 ip6_desync_factor; 1299 } else 1300 maxpltime = 0; 1301 1302 if (lt6_tmp.ia6t_vltime == ND6_INFINITE_LIFETIME || 1303 lt6_tmp.ia6t_vltime > maxvltime) { 1304 lt6_tmp.ia6t_vltime = maxvltime; 1305 } 1306 if (lt6_tmp.ia6t_pltime == ND6_INFINITE_LIFETIME || 1307 lt6_tmp.ia6t_pltime > maxpltime) { 1308 lt6_tmp.ia6t_pltime = maxpltime; 1309 } 1310 } 1311 1312 ifa6->ia6_lifetime = lt6_tmp; 1313 ifa6->ia6_updatetime = time_second; 1314 } 1315 if (ia6_match == NULL && new->ndpr_vltime) { 1316 int ifidlen; 1317 1318 /* 1319 * 5.5.3 (d) (continued) 1320 * No address matched and the valid lifetime is non-zero. 1321 * Create a new address. 1322 */ 1323 1324 /* 1325 * Prefix Length check: 1326 * If the sum of the prefix length and interface identifier 1327 * length does not equal 128 bits, the Prefix Information 1328 * option MUST be ignored. The length of the interface 1329 * identifier is defined in a separate link-type specific 1330 * document. 1331 */ 1332 ifidlen = in6_if2idlen(ifp); 1333 if (ifidlen < 0) { 1334 /* this should not happen, so we always log it. */ 1335 log(LOG_ERR, "prelist_update: IFID undefined (%s)\n", 1336 if_name(ifp)); 1337 goto end; 1338 } 1339 if (ifidlen + pr->ndpr_plen != 128) { 1340 nd6log((LOG_INFO, 1341 "prelist_update: invalid prefixlen " 1342 "%d for %s, ignored\n", 1343 pr->ndpr_plen, if_name(ifp))); 1344 goto end; 1345 } 1346 1347 if ((ia6 = in6_ifadd(new, mcast)) != NULL) { 1348 /* 1349 * note that we should use pr (not new) for reference. 1350 */ 1351 pr->ndpr_refcnt++; 1352 ia6->ia6_ndpr = pr; 1353 1354 /* 1355 * draft-ietf-ipngwg-temp-addresses-v2-00 3.3 (2). 1356 * When a new public address is created as described 1357 * in RFC2462, also create a new temporary address. 1358 * 1359 * draft-ietf-ipngwg-temp-addresses-v2-00 3.5. 1360 * When an interface connects to a new link, a new 1361 * randomized interface identifier should be generated 1362 * immediately together with a new set of temporary 1363 * addresses. Thus, we specifiy 1 as the 2nd arg of 1364 * in6_tmpifadd(). 1365 */ 1366 if (ip6_use_tempaddr) { 1367 int e; 1368 if ((e = in6_tmpifadd(ia6, 1, 1)) != 0) { 1369 nd6log((LOG_NOTICE, "prelist_update: " 1370 "failed to create a temporary " 1371 "address, errno=%d\n", 1372 e)); 1373 } 1374 } 1375 1376 /* 1377 * A newly added address might affect the status 1378 * of other addresses, so we check and update it. 1379 * XXX: what if address duplication happens? 1380 */ 1381 pfxlist_onlink_check(); 1382 } else { 1383 /* just set an error. do not bark here. */ 1384 error = EADDRNOTAVAIL; /* XXX: might be unused. */ 1385 } 1386 } 1387 1388 end: 1389 splx(s); 1390 return error; 1391} 1392 1393/* 1394 * A supplement function used in the on-link detection below; 1395 * detect if a given prefix has a (probably) reachable advertising router. 1396 * XXX: lengthy function name... 1397 */ 1398static struct nd_pfxrouter * 1399find_pfxlist_reachable_router(struct nd_prefix *pr) 1400{ 1401 struct nd_pfxrouter *pfxrtr; 1402 struct rtentry *rt; 1403 struct llinfo_nd6 *ln; 1404 1405 for (pfxrtr = LIST_FIRST(&pr->ndpr_advrtrs); pfxrtr; 1406 pfxrtr = LIST_NEXT(pfxrtr, pfr_entry)) { 1407 if ((rt = nd6_lookup(&pfxrtr->router->rtaddr, 0, 1408 pfxrtr->router->ifp)) && 1409 (ln = (struct llinfo_nd6 *)rt->rt_llinfo) && 1410 ND6_IS_LLINFO_PROBREACH(ln)) 1411 break; /* found */ 1412 } 1413 1414 return (pfxrtr); 1415} 1416 1417/* 1418 * Check if each prefix in the prefix list has at least one available router 1419 * that advertised the prefix (a router is "available" if its neighbor cache 1420 * entry is reachable or probably reachable). 1421 * If the check fails, the prefix may be off-link, because, for example, 1422 * we have moved from the network but the lifetime of the prefix has not 1423 * expired yet. So we should not use the prefix if there is another prefix 1424 * that has an available router. 1425 * But, if there is no prefix that has an available router, we still regards 1426 * all the prefixes as on-link. This is because we can't tell if all the 1427 * routers are simply dead or if we really moved from the network and there 1428 * is no router around us. 1429 */ 1430void 1431pfxlist_onlink_check(void) 1432{ 1433 struct nd_prefix *pr; 1434 struct in6_ifaddr *ifa; 1435 struct nd_defrouter *dr; 1436 struct nd_pfxrouter *pfxrtr = NULL; 1437 1438 /* 1439 * Check if there is a prefix that has a reachable advertising 1440 * router. 1441 */ 1442 LIST_FOREACH(pr, &nd_prefix, ndpr_entry) { 1443 if (pr->ndpr_raf_onlink && find_pfxlist_reachable_router(pr)) 1444 break; 1445 } 1446 /* 1447 * If we have no such prefix, check whether we still have a router 1448 * that does not advertise any prefixes. 1449 */ 1450 if (pr == NULL) { 1451 TAILQ_FOREACH(dr, &nd_defrouter, dr_entry) { 1452 struct nd_prefix *pr0; 1453 1454 LIST_FOREACH(pr0, &nd_prefix, ndpr_entry) { 1455 if ((pfxrtr = pfxrtr_lookup(pr0, dr)) != NULL) 1456 break; 1457 } 1458 if (pfxrtr) 1459 break; 1460 } 1461 } 1462 if (pr != NULL || (TAILQ_FIRST(&nd_defrouter) && !pfxrtr)) { 1463 /* 1464 * There is at least one prefix that has a reachable router, 1465 * or at least a router which probably does not advertise 1466 * any prefixes. The latter would be the case when we move 1467 * to a new link where we have a router that does not provide 1468 * prefixes and we configure an address by hand. 1469 * Detach prefixes which have no reachable advertising 1470 * router, and attach other prefixes. 1471 */ 1472 LIST_FOREACH(pr, &nd_prefix, ndpr_entry) { 1473 /* XXX: a link-local prefix should never be detached */ 1474 if (IN6_IS_ADDR_LINKLOCAL(&pr->ndpr_prefix.sin6_addr)) 1475 continue; 1476 1477 /* 1478 * we aren't interested in prefixes without the L bit 1479 * set. 1480 */ 1481 if (pr->ndpr_raf_onlink == 0) 1482 continue; 1483 1484 if ((pr->ndpr_stateflags & NDPRF_DETACHED) == 0 && 1485 find_pfxlist_reachable_router(pr) == NULL) 1486 pr->ndpr_stateflags |= NDPRF_DETACHED; 1487 if ((pr->ndpr_stateflags & NDPRF_DETACHED) != 0 && 1488 find_pfxlist_reachable_router(pr) != 0) 1489 pr->ndpr_stateflags &= ~NDPRF_DETACHED; 1490 } 1491 } else { 1492 /* there is no prefix that has a reachable router */ 1493 LIST_FOREACH(pr, &nd_prefix, ndpr_entry) { 1494 if (IN6_IS_ADDR_LINKLOCAL(&pr->ndpr_prefix.sin6_addr)) 1495 continue; 1496 1497 if (pr->ndpr_raf_onlink == 0) 1498 continue; 1499 1500 if ((pr->ndpr_stateflags & NDPRF_DETACHED) != 0) 1501 pr->ndpr_stateflags &= ~NDPRF_DETACHED; 1502 } 1503 } 1504 1505 /* 1506 * Remove each interface route associated with a (just) detached 1507 * prefix, and reinstall the interface route for a (just) attached 1508 * prefix. Note that all attempt of reinstallation does not 1509 * necessarily success, when a same prefix is shared among multiple 1510 * interfaces. Such cases will be handled in nd6_prefix_onlink, 1511 * so we don't have to care about them. 1512 */ 1513 LIST_FOREACH(pr, &nd_prefix, ndpr_entry) { 1514 int e; 1515 1516 if (IN6_IS_ADDR_LINKLOCAL(&pr->ndpr_prefix.sin6_addr)) 1517 continue; 1518 1519 if (pr->ndpr_raf_onlink == 0) 1520 continue; 1521 1522 if ((pr->ndpr_stateflags & NDPRF_DETACHED) != 0 && 1523 (pr->ndpr_stateflags & NDPRF_ONLINK) != 0) { 1524 if ((e = nd6_prefix_offlink(pr)) != 0) { 1525 nd6log((LOG_ERR, 1526 "pfxlist_onlink_check: failed to " 1527 "make %s/%d offlink, errno=%d\n", 1528 ip6_sprintf(&pr->ndpr_prefix.sin6_addr), 1529 pr->ndpr_plen, e)); 1530 } 1531 } 1532 if ((pr->ndpr_stateflags & NDPRF_DETACHED) == 0 && 1533 (pr->ndpr_stateflags & NDPRF_ONLINK) == 0 && 1534 pr->ndpr_raf_onlink) { 1535 if ((e = nd6_prefix_onlink(pr)) != 0) { 1536 nd6log((LOG_ERR, 1537 "pfxlist_onlink_check: failed to " 1538 "make %s/%d onlink, errno=%d\n", 1539 ip6_sprintf(&pr->ndpr_prefix.sin6_addr), 1540 pr->ndpr_plen, e)); 1541 } 1542 } 1543 } 1544 1545 /* 1546 * Changes on the prefix status might affect address status as well. 1547 * Make sure that all addresses derived from an attached prefix are 1548 * attached, and that all addresses derived from a detached prefix are 1549 * detached. Note, however, that a manually configured address should 1550 * always be attached. 1551 * The precise detection logic is same as the one for prefixes. 1552 */ 1553 for (ifa = in6_ifaddr; ifa; ifa = ifa->ia_next) { 1554 if (!(ifa->ia6_flags & IN6_IFF_AUTOCONF)) 1555 continue; 1556 1557 if (ifa->ia6_ndpr == NULL) { 1558 /* 1559 * This can happen when we first configure the address 1560 * (i.e. the address exists, but the prefix does not). 1561 * XXX: complicated relationships... 1562 */ 1563 continue; 1564 } 1565 1566 if (find_pfxlist_reachable_router(ifa->ia6_ndpr)) 1567 break; 1568 } 1569 if (ifa) { 1570 for (ifa = in6_ifaddr; ifa; ifa = ifa->ia_next) { 1571 if ((ifa->ia6_flags & IN6_IFF_AUTOCONF) == 0) 1572 continue; 1573 1574 if (ifa->ia6_ndpr == NULL) /* XXX: see above. */ 1575 continue; 1576 1577 if (find_pfxlist_reachable_router(ifa->ia6_ndpr)) { 1578 if (ifa->ia6_flags & IN6_IFF_DETACHED) { 1579 ifa->ia6_flags &= ~IN6_IFF_DETACHED; 1580 ifa->ia6_flags |= IN6_IFF_TENTATIVE; 1581 nd6_dad_start((struct ifaddr *)ifa, 1582 0); 1583 } 1584 } else { 1585 if ((ifa->ia6_flags & IN6_IFF_DETACHED) == 0) { 1586 ifa->ia6_flags |= IN6_IFF_DETACHED; 1587 } 1588 } 1589 } 1590 } 1591 else { 1592 for (ifa = in6_ifaddr; ifa; ifa = ifa->ia_next) { 1593 if ((ifa->ia6_flags & IN6_IFF_AUTOCONF) == 0) 1594 continue; 1595 1596 if (ifa->ia6_flags & IN6_IFF_DETACHED) { 1597 ifa->ia6_flags &= ~IN6_IFF_DETACHED; 1598 ifa->ia6_flags |= IN6_IFF_TENTATIVE; 1599 /* Do we need a delay in this case? */ 1600 nd6_dad_start((struct ifaddr *)ifa, 0); 1601 } 1602 } 1603 } 1604} 1605 1606int 1607nd6_prefix_onlink(struct nd_prefix *pr) 1608{ 1609 struct ifaddr *ifa; 1610 struct ifnet *ifp = pr->ndpr_ifp; 1611 struct sockaddr_in6 mask6; 1612 struct nd_prefix *opr; 1613 u_long rtflags; 1614 int error = 0; 1615 struct rtentry *rt = NULL; 1616 1617 /* sanity check */ 1618 if ((pr->ndpr_stateflags & NDPRF_ONLINK) != 0) { 1619 nd6log((LOG_ERR, 1620 "nd6_prefix_onlink: %s/%d is already on-link\n", 1621 ip6_sprintf(&pr->ndpr_prefix.sin6_addr), pr->ndpr_plen)); 1622 return (EEXIST); 1623 } 1624 1625 /* 1626 * Add the interface route associated with the prefix. Before 1627 * installing the route, check if there's the same prefix on another 1628 * interface, and the prefix has already installed the interface route. 1629 * Although such a configuration is expected to be rare, we explicitly 1630 * allow it. 1631 */ 1632 LIST_FOREACH(opr, &nd_prefix, ndpr_entry) { 1633 if (opr == pr) 1634 continue; 1635 1636 if ((opr->ndpr_stateflags & NDPRF_ONLINK) == 0) 1637 continue; 1638 1639 if (opr->ndpr_plen == pr->ndpr_plen && 1640 in6_are_prefix_equal(&pr->ndpr_prefix.sin6_addr, 1641 &opr->ndpr_prefix.sin6_addr, pr->ndpr_plen)) 1642 return (0); 1643 } 1644 1645 /* 1646 * We prefer link-local addresses as the associated interface address. 1647 */ 1648 /* search for a link-local addr */ 1649 ifa = (struct ifaddr *)in6ifa_ifpforlinklocal(ifp, 1650 IN6_IFF_NOTREADY | IN6_IFF_ANYCAST); 1651 if (ifa == NULL) { 1652 /* XXX: freebsd does not have ifa_ifwithaf */ 1653 IFADDR_FOREACH(ifa, ifp) { 1654 if (ifa->ifa_addr->sa_family == AF_INET6) 1655 break; 1656 } 1657 /* should we care about ia6_flags? */ 1658 } 1659 if (ifa == NULL) { 1660 /* 1661 * This can still happen, when, for example, we receive an RA 1662 * containing a prefix with the L bit set and the A bit clear, 1663 * after removing all IPv6 addresses on the receiving 1664 * interface. This should, of course, be rare though. 1665 */ 1666 nd6log((LOG_NOTICE, 1667 "nd6_prefix_onlink: failed to find any ifaddr" 1668 " to add route for a prefix(%s/%d) on %s\n", 1669 ip6_sprintf(&pr->ndpr_prefix.sin6_addr), 1670 pr->ndpr_plen, if_name(ifp))); 1671 return (0); 1672 } 1673 1674 /* 1675 * in6_ifinit() sets nd6_rtrequest to ifa_rtrequest for all ifaddrs. 1676 * ifa->ifa_rtrequest = nd6_rtrequest; 1677 */ 1678 memset(&mask6, 0, sizeof(mask6)); 1679 mask6.sin6_len = sizeof(mask6); 1680 mask6.sin6_addr = pr->ndpr_mask; 1681 /* rtrequest() will probably set RTF_UP, but we're not sure. */ 1682 rtflags = ifa->ifa_flags | RTF_UP; 1683 if (nd6_need_cache(ifp)) { 1684 /* explicitly set in case ifa_flags does not set the flag. */ 1685 rtflags |= RTF_CLONING; 1686 } else { 1687 /* 1688 * explicitly clear the cloning bit in case ifa_flags sets it. 1689 */ 1690 rtflags &= ~RTF_CLONING; 1691 } 1692 error = rtrequest(RTM_ADD, (struct sockaddr *)&pr->ndpr_prefix, 1693 ifa->ifa_addr, (struct sockaddr *)&mask6, rtflags, &rt); 1694 if (error == 0) { 1695 if (rt != NULL) { /* this should be non NULL, though */ 1696 nd6_rtmsg(RTM_ADD, rt); 1697 nd6_numroutes++; 1698 } 1699 pr->ndpr_stateflags |= NDPRF_ONLINK; 1700 } else { 1701 nd6log((LOG_ERR, "nd6_prefix_onlink: failed to add route for a" 1702 " prefix (%s/%d) on %s, gw=%s, mask=%s, flags=%lx " 1703 "errno = %d\n", 1704 ip6_sprintf(&pr->ndpr_prefix.sin6_addr), 1705 pr->ndpr_plen, if_name(ifp), 1706 ip6_sprintf(&((struct sockaddr_in6 *)ifa->ifa_addr)->sin6_addr), 1707 ip6_sprintf(&mask6.sin6_addr), rtflags, error)); 1708 } 1709 1710 if (rt != NULL) 1711 rt->rt_refcnt--; 1712 1713 return (error); 1714} 1715 1716int 1717nd6_prefix_offlink(struct nd_prefix *pr) 1718{ 1719 int error = 0; 1720 struct ifnet *ifp = pr->ndpr_ifp; 1721 struct nd_prefix *opr; 1722 struct sockaddr_in6 sa6, mask6; 1723 struct rtentry *rt = NULL; 1724 1725 /* sanity check */ 1726 if ((pr->ndpr_stateflags & NDPRF_ONLINK) == 0) { 1727 nd6log((LOG_ERR, 1728 "nd6_prefix_offlink: %s/%d is already off-link\n", 1729 ip6_sprintf(&pr->ndpr_prefix.sin6_addr), pr->ndpr_plen)); 1730 return (EEXIST); 1731 } 1732 1733 sockaddr_in6_init(&sa6, &pr->ndpr_prefix.sin6_addr, 0, 0, 0); 1734 sockaddr_in6_init(&mask6, &pr->ndpr_mask, 0, 0, 0); 1735 error = rtrequest(RTM_DELETE, (struct sockaddr *)&sa6, NULL, 1736 (struct sockaddr *)&mask6, 0, &rt); 1737 if (error == 0) { 1738 pr->ndpr_stateflags &= ~NDPRF_ONLINK; 1739 1740 /* report the route deletion to the routing socket. */ 1741 if (rt != NULL) { 1742 nd6_rtmsg(RTM_DELETE, rt); 1743 nd6_numroutes--; 1744 } 1745 1746 /* 1747 * There might be the same prefix on another interface, 1748 * the prefix which could not be on-link just because we have 1749 * the interface route (see comments in nd6_prefix_onlink). 1750 * If there's one, try to make the prefix on-link on the 1751 * interface. 1752 */ 1753 LIST_FOREACH(opr, &nd_prefix, ndpr_entry) { 1754 if (opr == pr) 1755 continue; 1756 1757 if ((opr->ndpr_stateflags & NDPRF_ONLINK) != 0) 1758 continue; 1759 1760 /* 1761 * KAME specific: detached prefixes should not be 1762 * on-link. 1763 */ 1764 if ((opr->ndpr_stateflags & NDPRF_DETACHED) != 0) 1765 continue; 1766 1767 if (opr->ndpr_plen == pr->ndpr_plen && 1768 in6_are_prefix_equal(&pr->ndpr_prefix.sin6_addr, 1769 &opr->ndpr_prefix.sin6_addr, pr->ndpr_plen)) { 1770 int e; 1771 1772 if ((e = nd6_prefix_onlink(opr)) != 0) { 1773 nd6log((LOG_ERR, 1774 "nd6_prefix_offlink: failed to " 1775 "recover a prefix %s/%d from %s " 1776 "to %s (errno = %d)\n", 1777 ip6_sprintf(&opr->ndpr_prefix.sin6_addr), 1778 opr->ndpr_plen, if_name(ifp), 1779 if_name(opr->ndpr_ifp), e)); 1780 } 1781 } 1782 } 1783 } else { 1784 /* XXX: can we still set the NDPRF_ONLINK flag? */ 1785 nd6log((LOG_ERR, 1786 "nd6_prefix_offlink: failed to delete route: " 1787 "%s/%d on %s (errno = %d)\n", 1788 ip6_sprintf(&sa6.sin6_addr), pr->ndpr_plen, if_name(ifp), 1789 error)); 1790 } 1791 1792 if (rt != NULL) { 1793 if (rt->rt_refcnt <= 0) { 1794 /* XXX: we should free the entry ourselves. */ 1795 rt->rt_refcnt++; 1796 rtfree(rt); 1797 } 1798 } 1799 1800 return (error); 1801} 1802 1803static struct in6_ifaddr * 1804in6_ifadd(struct nd_prefixctl *pr, int mcast) 1805{ 1806 struct ifnet *ifp = pr->ndpr_ifp; 1807 struct ifaddr *ifa; 1808 struct in6_aliasreq ifra; 1809 struct in6_ifaddr *ia, *ib; 1810 int error, plen0; 1811 struct in6_addr mask; 1812 int prefixlen = pr->ndpr_plen; 1813 int updateflags; 1814 1815 in6_prefixlen2mask(&mask, prefixlen); 1816 1817 /* 1818 * find a link-local address (will be interface ID). 1819 * Is it really mandatory? Theoretically, a global or a site-local 1820 * address can be configured without a link-local address, if we 1821 * have a unique interface identifier... 1822 * 1823 * it is not mandatory to have a link-local address, we can generate 1824 * interface identifier on the fly. we do this because: 1825 * (1) it should be the easiest way to find interface identifier. 1826 * (2) RFC2462 5.4 suggesting the use of the same interface identifier 1827 * for multiple addresses on a single interface, and possible shortcut 1828 * of DAD. we omitted DAD for this reason in the past. 1829 * (3) a user can prevent autoconfiguration of global address 1830 * by removing link-local address by hand (this is partly because we 1831 * don't have other way to control the use of IPv6 on an interface. 1832 * this has been our design choice - cf. NRL's "ifconfig auto"). 1833 * (4) it is easier to manage when an interface has addresses 1834 * with the same interface identifier, than to have multiple addresses 1835 * with different interface identifiers. 1836 */ 1837 ifa = (struct ifaddr *)in6ifa_ifpforlinklocal(ifp, 0); /* 0 is OK? */ 1838 if (ifa) 1839 ib = (struct in6_ifaddr *)ifa; 1840 else 1841 return NULL; 1842 1843#if 0 /* don't care link local addr state, and always do DAD */ 1844 /* if link-local address is not eligible, do not autoconfigure. */ 1845 if (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_NOTREADY) { 1846 printf("in6_ifadd: link-local address not ready\n"); 1847 return NULL; 1848 } 1849#endif 1850 1851 /* prefixlen + ifidlen must be equal to 128 */ 1852 plen0 = in6_mask2len(&ib->ia_prefixmask.sin6_addr, NULL); 1853 if (prefixlen != plen0) { 1854 nd6log((LOG_INFO, "in6_ifadd: wrong prefixlen for %s " 1855 "(prefix=%d ifid=%d)\n", 1856 if_name(ifp), prefixlen, 128 - plen0)); 1857 return NULL; 1858 } 1859 1860 /* make ifaddr */ 1861 1862 memset(&ifra, 0, sizeof(ifra)); 1863 /* 1864 * in6_update_ifa() does not use ifra_name, but we accurately set it 1865 * for safety. 1866 */ 1867 strncpy(ifra.ifra_name, if_name(ifp), sizeof(ifra.ifra_name)); 1868 sockaddr_in6_init(&ifra.ifra_addr, &pr->ndpr_prefix.sin6_addr, 0, 0, 0); 1869 /* prefix */ 1870 ifra.ifra_addr.sin6_addr.s6_addr32[0] &= mask.s6_addr32[0]; 1871 ifra.ifra_addr.sin6_addr.s6_addr32[1] &= mask.s6_addr32[1]; 1872 ifra.ifra_addr.sin6_addr.s6_addr32[2] &= mask.s6_addr32[2]; 1873 ifra.ifra_addr.sin6_addr.s6_addr32[3] &= mask.s6_addr32[3]; 1874 1875 /* interface ID */ 1876 ifra.ifra_addr.sin6_addr.s6_addr32[0] |= 1877 (ib->ia_addr.sin6_addr.s6_addr32[0] & ~mask.s6_addr32[0]); 1878 ifra.ifra_addr.sin6_addr.s6_addr32[1] |= 1879 (ib->ia_addr.sin6_addr.s6_addr32[1] & ~mask.s6_addr32[1]); 1880 ifra.ifra_addr.sin6_addr.s6_addr32[2] |= 1881 (ib->ia_addr.sin6_addr.s6_addr32[2] & ~mask.s6_addr32[2]); 1882 ifra.ifra_addr.sin6_addr.s6_addr32[3] |= 1883 (ib->ia_addr.sin6_addr.s6_addr32[3] & ~mask.s6_addr32[3]); 1884 1885 /* new prefix mask. */ 1886 sockaddr_in6_init(&ifra.ifra_prefixmask, &mask, 0, 0, 0); 1887 1888 /* lifetimes */ 1889 ifra.ifra_lifetime.ia6t_vltime = pr->ndpr_vltime; 1890 ifra.ifra_lifetime.ia6t_pltime = pr->ndpr_pltime; 1891 1892 /* XXX: scope zone ID? */ 1893 1894 ifra.ifra_flags |= IN6_IFF_AUTOCONF; /* obey autoconf */ 1895 1896 /* 1897 * Make sure that we do not have this address already. This should 1898 * usually not happen, but we can still see this case, e.g., if we 1899 * have manually configured the exact address to be configured. 1900 */ 1901 if (in6ifa_ifpwithaddr(ifp, &ifra.ifra_addr.sin6_addr) != NULL) { 1902 /* this should be rare enough to make an explicit log */ 1903 log(LOG_INFO, "in6_ifadd: %s is already configured\n", 1904 ip6_sprintf(&ifra.ifra_addr.sin6_addr)); 1905 return (NULL); 1906 } 1907 1908 /* 1909 * Allocate ifaddr structure, link into chain, etc. 1910 * If we are going to create a new address upon receiving a multicasted 1911 * RA, we need to impose a random delay before starting DAD. 1912 * [draft-ietf-ipv6-rfc2462bis-02.txt, Section 5.4.2] 1913 */ 1914 updateflags = 0; 1915 if (mcast) 1916 updateflags |= IN6_IFAUPDATE_DADDELAY; 1917 if ((error = in6_update_ifa(ifp, &ifra, NULL, updateflags)) != 0) { 1918 nd6log((LOG_ERR, 1919 "in6_ifadd: failed to make ifaddr %s on %s (errno=%d)\n", 1920 ip6_sprintf(&ifra.ifra_addr.sin6_addr), if_name(ifp), 1921 error)); 1922 return (NULL); /* ifaddr must not have been allocated. */ 1923 } 1924 1925 ia = in6ifa_ifpwithaddr(ifp, &ifra.ifra_addr.sin6_addr); 1926 1927 return (ia); /* this is always non-NULL */ 1928} 1929 1930int 1931in6_tmpifadd( 1932 const struct in6_ifaddr *ia0, /* corresponding public address */ 1933 int forcegen, 1934 int dad_delay) 1935{ 1936 struct ifnet *ifp = ia0->ia_ifa.ifa_ifp; 1937 struct in6_ifaddr *newia, *ia; 1938 struct in6_aliasreq ifra; 1939 int i, error; 1940 int trylimit = 3; /* XXX: adhoc value */ 1941 int updateflags; 1942 u_int32_t randid[2]; 1943 u_int32_t vltime0, pltime0; 1944 1945 memset(&ifra, 0, sizeof(ifra)); 1946 strncpy(ifra.ifra_name, if_name(ifp), sizeof(ifra.ifra_name)); 1947 ifra.ifra_addr = ia0->ia_addr; 1948 /* copy prefix mask */ 1949 ifra.ifra_prefixmask = ia0->ia_prefixmask; 1950 /* clear the old IFID */ 1951 for (i = 0; i < 4; i++) { 1952 ifra.ifra_addr.sin6_addr.s6_addr32[i] &= 1953 ifra.ifra_prefixmask.sin6_addr.s6_addr32[i]; 1954 } 1955 1956 again: 1957 if (in6_get_tmpifid(ifp, (u_int8_t *)randid, 1958 (const u_int8_t *)&ia0->ia_addr.sin6_addr.s6_addr[8], forcegen)) { 1959 nd6log((LOG_NOTICE, "in6_tmpifadd: failed to find a good " 1960 "random IFID\n")); 1961 return (EINVAL); 1962 } 1963 ifra.ifra_addr.sin6_addr.s6_addr32[2] |= 1964 (randid[0] & ~(ifra.ifra_prefixmask.sin6_addr.s6_addr32[2])); 1965 ifra.ifra_addr.sin6_addr.s6_addr32[3] |= 1966 (randid[1] & ~(ifra.ifra_prefixmask.sin6_addr.s6_addr32[3])); 1967 1968 /* 1969 * in6_get_tmpifid() quite likely provided a unique interface ID. 1970 * However, we may still have a chance to see collision, because 1971 * there may be a time lag between generation of the ID and generation 1972 * of the address. So, we'll do one more sanity check. 1973 */ 1974 for (ia = in6_ifaddr; ia; ia = ia->ia_next) { 1975 if (IN6_ARE_ADDR_EQUAL(&ia->ia_addr.sin6_addr, 1976 &ifra.ifra_addr.sin6_addr)) { 1977 if (trylimit-- == 0) { 1978 /* 1979 * Give up. Something strange should have 1980 * happened. 1981 */ 1982 nd6log((LOG_NOTICE, "in6_tmpifadd: failed to " 1983 "find a unique random IFID\n")); 1984 return (EEXIST); 1985 } 1986 forcegen = 1; 1987 goto again; 1988 } 1989 } 1990 1991 /* 1992 * The Valid Lifetime is the lower of the Valid Lifetime of the 1993 * public address or TEMP_VALID_LIFETIME. 1994 * The Preferred Lifetime is the lower of the Preferred Lifetime 1995 * of the public address or TEMP_PREFERRED_LIFETIME - 1996 * DESYNC_FACTOR. 1997 */ 1998 if (ia0->ia6_lifetime.ia6t_vltime != ND6_INFINITE_LIFETIME) { 1999 vltime0 = IFA6_IS_INVALID(ia0) ? 0 : 2000 (ia0->ia6_lifetime.ia6t_vltime - 2001 (time_second - ia0->ia6_updatetime)); 2002 if (vltime0 > ip6_temp_valid_lifetime) 2003 vltime0 = ip6_temp_valid_lifetime; 2004 } else 2005 vltime0 = ip6_temp_valid_lifetime; 2006 if (ia0->ia6_lifetime.ia6t_pltime != ND6_INFINITE_LIFETIME) { 2007 pltime0 = IFA6_IS_DEPRECATED(ia0) ? 0 : 2008 (ia0->ia6_lifetime.ia6t_pltime - 2009 (time_second - ia0->ia6_updatetime)); 2010 if (pltime0 > ip6_temp_preferred_lifetime - ip6_desync_factor){ 2011 pltime0 = ip6_temp_preferred_lifetime - 2012 ip6_desync_factor; 2013 } 2014 } else 2015 pltime0 = ip6_temp_preferred_lifetime - ip6_desync_factor; 2016 ifra.ifra_lifetime.ia6t_vltime = vltime0; 2017 ifra.ifra_lifetime.ia6t_pltime = pltime0; 2018 2019 /* 2020 * A temporary address is created only if this calculated Preferred 2021 * Lifetime is greater than REGEN_ADVANCE time units. 2022 */ 2023 if (ifra.ifra_lifetime.ia6t_pltime <= ip6_temp_regen_advance) 2024 return (0); 2025 2026 /* XXX: scope zone ID? */ 2027 2028 ifra.ifra_flags |= (IN6_IFF_AUTOCONF|IN6_IFF_TEMPORARY); 2029 2030 /* allocate ifaddr structure, link into chain, etc. */ 2031 updateflags = 0; 2032 if (dad_delay) 2033 updateflags |= IN6_IFAUPDATE_DADDELAY; 2034 if ((error = in6_update_ifa(ifp, &ifra, NULL, updateflags)) != 0) 2035 return (error); 2036 2037 newia = in6ifa_ifpwithaddr(ifp, &ifra.ifra_addr.sin6_addr); 2038 if (newia == NULL) { /* XXX: can it happen? */ 2039 nd6log((LOG_ERR, 2040 "in6_tmpifadd: ifa update succeeded, but we got " 2041 "no ifaddr\n")); 2042 return (EINVAL); /* XXX */ 2043 } 2044 newia->ia6_ndpr = ia0->ia6_ndpr; 2045 newia->ia6_ndpr->ndpr_refcnt++; 2046 2047 /* 2048 * A newly added address might affect the status of other addresses. 2049 * XXX: when the temporary address is generated with a new public 2050 * address, the onlink check is redundant. However, it would be safe 2051 * to do the check explicitly everywhere a new address is generated, 2052 * and, in fact, we surely need the check when we create a new 2053 * temporary address due to deprecation of an old temporary address. 2054 */ 2055 pfxlist_onlink_check(); 2056 2057 return (0); 2058} 2059 2060static int 2061in6_init_prefix_ltimes(struct nd_prefix *ndpr) 2062{ 2063 2064 /* check if preferred lifetime > valid lifetime. RFC2462 5.5.3 (c) */ 2065 if (ndpr->ndpr_pltime > ndpr->ndpr_vltime) { 2066 nd6log((LOG_INFO, "in6_init_prefix_ltimes: preferred lifetime" 2067 "(%d) is greater than valid lifetime(%d)\n", 2068 (u_int)ndpr->ndpr_pltime, (u_int)ndpr->ndpr_vltime)); 2069 return (EINVAL); 2070 } 2071 if (ndpr->ndpr_pltime == ND6_INFINITE_LIFETIME) 2072 ndpr->ndpr_preferred = 0; 2073 else 2074 ndpr->ndpr_preferred = time_second + ndpr->ndpr_pltime; 2075 if (ndpr->ndpr_vltime == ND6_INFINITE_LIFETIME) 2076 ndpr->ndpr_expire = 0; 2077 else 2078 ndpr->ndpr_expire = time_second + ndpr->ndpr_vltime; 2079 2080 return 0; 2081} 2082 2083static void 2084in6_init_address_ltimes(struct nd_prefix *new, 2085 struct in6_addrlifetime *lt6) 2086{ 2087 2088 /* Valid lifetime must not be updated unless explicitly specified. */ 2089 /* init ia6t_expire */ 2090 if (lt6->ia6t_vltime == ND6_INFINITE_LIFETIME) 2091 lt6->ia6t_expire = 0; 2092 else { 2093 lt6->ia6t_expire = time_second; 2094 lt6->ia6t_expire += lt6->ia6t_vltime; 2095 } 2096 2097 /* init ia6t_preferred */ 2098 if (lt6->ia6t_pltime == ND6_INFINITE_LIFETIME) 2099 lt6->ia6t_preferred = 0; 2100 else { 2101 lt6->ia6t_preferred = time_second; 2102 lt6->ia6t_preferred += lt6->ia6t_pltime; 2103 } 2104} 2105 2106/* 2107 * Delete all the routing table entries that use the specified gateway. 2108 * XXX: this function causes search through all entries of routing table, so 2109 * it shouldn't be called when acting as a router. 2110 */ 2111void 2112rt6_flush(struct in6_addr *gateway, struct ifnet *ifp) 2113{ 2114 int s = splsoftnet(); 2115 2116 /* We'll care only link-local addresses */ 2117 if (!IN6_IS_ADDR_LINKLOCAL(gateway)) { 2118 splx(s); 2119 return; 2120 } 2121 2122 rt_walktree(AF_INET6, rt6_deleteroute, (void *)gateway); 2123 splx(s); 2124} 2125 2126static int 2127rt6_deleteroute(struct rtentry *rt, void *arg) 2128{ 2129#define SIN6(s) ((struct sockaddr_in6 *)s) 2130 struct in6_addr *gate = (struct in6_addr *)arg; 2131 2132 if (rt->rt_gateway == NULL || rt->rt_gateway->sa_family != AF_INET6) 2133 return (0); 2134 2135 if (!IN6_ARE_ADDR_EQUAL(gate, &SIN6(rt->rt_gateway)->sin6_addr)) 2136 return (0); 2137 2138 /* 2139 * Do not delete a static route. 2140 * XXX: this seems to be a bit ad-hoc. Should we consider the 2141 * 'cloned' bit instead? 2142 */ 2143 if ((rt->rt_flags & RTF_STATIC) != 0) 2144 return (0); 2145 2146 /* 2147 * We delete only host route. This means, in particular, we don't 2148 * delete default route. 2149 */ 2150 if ((rt->rt_flags & RTF_HOST) == 0) 2151 return (0); 2152 2153 return (rtrequest(RTM_DELETE, rt_getkey(rt), rt->rt_gateway, 2154 rt_mask(rt), rt->rt_flags, 0)); 2155#undef SIN6 2156} 2157 2158int 2159nd6_setdefaultiface(int ifindex) 2160{ 2161 int error = 0; 2162 2163 if (ifindex < 0 || if_indexlim <= ifindex) 2164 return (EINVAL); 2165 if (ifindex != 0 && !ifindex2ifnet[ifindex]) 2166 return (EINVAL); 2167 2168 if (nd6_defifindex != ifindex) { 2169 nd6_defifindex = ifindex; 2170 if (nd6_defifindex > 0) { 2171 nd6_defifp = ifindex2ifnet[nd6_defifindex]; 2172 } else 2173 nd6_defifp = NULL; 2174 2175 /* 2176 * Our current implementation assumes one-to-one maping between 2177 * interfaces and links, so it would be natural to use the 2178 * default interface as the default link. 2179 */ 2180 scope6_setdefault(nd6_defifp); 2181 } 2182 2183 return (error); 2184} 2185