nd6_rtr.c revision 222728
1/*- 2 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project. 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. Neither the name of the project nor the names of its contributors 14 * may be used to endorse or promote products derived from this software 15 * without specific prior written permission. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE 21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * SUCH DAMAGE. 28 * 29 * $KAME: nd6_rtr.c,v 1.111 2001/04/27 01:37:15 jinmei Exp $ 30 */ 31 32#include <sys/cdefs.h> 33__FBSDID("$FreeBSD: head/sys/netinet6/nd6_rtr.c 222728 2011-06-06 02:14:23Z hrs $"); 34 35#include "opt_inet.h" 36#include "opt_inet6.h" 37 38#include <sys/param.h> 39#include <sys/systm.h> 40#include <sys/malloc.h> 41#include <sys/mbuf.h> 42#include <sys/socket.h> 43#include <sys/sockio.h> 44#include <sys/time.h> 45#include <sys/kernel.h> 46#include <sys/lock.h> 47#include <sys/errno.h> 48#include <sys/rwlock.h> 49#include <sys/syslog.h> 50#include <sys/queue.h> 51 52#include <net/if.h> 53#include <net/if_types.h> 54#include <net/if_dl.h> 55#include <net/route.h> 56#include <net/radix.h> 57#include <net/vnet.h> 58 59#include <netinet/in.h> 60#include <net/if_llatbl.h> 61#include <netinet6/in6_var.h> 62#include <netinet6/in6_ifattach.h> 63#include <netinet/ip6.h> 64#include <netinet6/ip6_var.h> 65#include <netinet6/nd6.h> 66#include <netinet/icmp6.h> 67#include <netinet6/scope6_var.h> 68 69static int rtpref(struct nd_defrouter *); 70static struct nd_defrouter *defrtrlist_update(struct nd_defrouter *); 71static int prelist_update __P((struct nd_prefixctl *, struct nd_defrouter *, 72 struct mbuf *, int)); 73static struct in6_ifaddr *in6_ifadd(struct nd_prefixctl *, int); 74static struct nd_pfxrouter *pfxrtr_lookup __P((struct nd_prefix *, 75 struct nd_defrouter *)); 76static void pfxrtr_add(struct nd_prefix *, struct nd_defrouter *); 77static void pfxrtr_del(struct nd_pfxrouter *); 78static struct nd_pfxrouter *find_pfxlist_reachable_router 79(struct nd_prefix *); 80static void defrouter_delreq(struct nd_defrouter *); 81static void nd6_rtmsg(int, struct rtentry *); 82 83static int in6_init_prefix_ltimes(struct nd_prefix *); 84static void in6_init_address_ltimes __P((struct nd_prefix *, 85 struct in6_addrlifetime *)); 86 87static int rt6_deleteroute(struct radix_node *, void *); 88 89VNET_DECLARE(int, nd6_recalc_reachtm_interval); 90#define V_nd6_recalc_reachtm_interval VNET(nd6_recalc_reachtm_interval) 91 92static VNET_DEFINE(struct ifnet *, nd6_defifp); 93VNET_DEFINE(int, nd6_defifindex); 94#define V_nd6_defifp VNET(nd6_defifp) 95 96VNET_DEFINE(int, ip6_use_tempaddr) = 0; 97 98VNET_DEFINE(int, ip6_desync_factor); 99VNET_DEFINE(u_int32_t, ip6_temp_preferred_lifetime) = DEF_TEMP_PREFERRED_LIFETIME; 100VNET_DEFINE(u_int32_t, ip6_temp_valid_lifetime) = DEF_TEMP_VALID_LIFETIME; 101 102VNET_DEFINE(int, ip6_temp_regen_advance) = TEMPADDR_REGEN_ADVANCE; 103 104/* RTPREF_MEDIUM has to be 0! */ 105#define RTPREF_HIGH 1 106#define RTPREF_MEDIUM 0 107#define RTPREF_LOW (-1) 108#define RTPREF_RESERVED (-2) 109#define RTPREF_INVALID (-3) /* internal */ 110 111/* 112 * Receive Router Solicitation Message - just for routers. 113 * Router solicitation/advertisement is mostly managed by userland program 114 * (rtadvd) so here we have no function like nd6_ra_output(). 115 * 116 * Based on RFC 2461 117 */ 118void 119nd6_rs_input(struct mbuf *m, int off, int icmp6len) 120{ 121 struct ifnet *ifp = m->m_pkthdr.rcvif; 122 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 123 struct nd_router_solicit *nd_rs; 124 struct in6_addr saddr6 = ip6->ip6_src; 125 char *lladdr = NULL; 126 int lladdrlen = 0; 127 union nd_opts ndopts; 128 char ip6bufs[INET6_ADDRSTRLEN], ip6bufd[INET6_ADDRSTRLEN]; 129 130 /* 131 * Accept RS only when V_ip6_forwarding=1 and the interface has 132 * no ND6_IFF_ACCEPT_RTADV. 133 */ 134 if (!V_ip6_forwarding || ND_IFINFO(ifp)->flags & ND6_IFF_ACCEPT_RTADV) 135 goto freeit; 136 137 /* Sanity checks */ 138 if (ip6->ip6_hlim != 255) { 139 nd6log((LOG_ERR, 140 "nd6_rs_input: invalid hlim (%d) from %s to %s on %s\n", 141 ip6->ip6_hlim, ip6_sprintf(ip6bufs, &ip6->ip6_src), 142 ip6_sprintf(ip6bufd, &ip6->ip6_dst), if_name(ifp))); 143 goto bad; 144 } 145 146 /* 147 * Don't update the neighbor cache, if src = ::. 148 * This indicates that the src has no IP address assigned yet. 149 */ 150 if (IN6_IS_ADDR_UNSPECIFIED(&saddr6)) 151 goto freeit; 152 153#ifndef PULLDOWN_TEST 154 IP6_EXTHDR_CHECK(m, off, icmp6len,); 155 nd_rs = (struct nd_router_solicit *)((caddr_t)ip6 + off); 156#else 157 IP6_EXTHDR_GET(nd_rs, struct nd_router_solicit *, m, off, icmp6len); 158 if (nd_rs == NULL) { 159 ICMP6STAT_INC(icp6s_tooshort); 160 return; 161 } 162#endif 163 164 icmp6len -= sizeof(*nd_rs); 165 nd6_option_init(nd_rs + 1, icmp6len, &ndopts); 166 if (nd6_options(&ndopts) < 0) { 167 nd6log((LOG_INFO, 168 "nd6_rs_input: invalid ND option, ignored\n")); 169 /* nd6_options have incremented stats */ 170 goto freeit; 171 } 172 173 if (ndopts.nd_opts_src_lladdr) { 174 lladdr = (char *)(ndopts.nd_opts_src_lladdr + 1); 175 lladdrlen = ndopts.nd_opts_src_lladdr->nd_opt_len << 3; 176 } 177 178 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) { 179 nd6log((LOG_INFO, 180 "nd6_rs_input: lladdrlen mismatch for %s " 181 "(if %d, RS packet %d)\n", 182 ip6_sprintf(ip6bufs, &saddr6), 183 ifp->if_addrlen, lladdrlen - 2)); 184 goto bad; 185 } 186 187 nd6_cache_lladdr(ifp, &saddr6, lladdr, lladdrlen, ND_ROUTER_SOLICIT, 0); 188 189 freeit: 190 m_freem(m); 191 return; 192 193 bad: 194 ICMP6STAT_INC(icp6s_badrs); 195 m_freem(m); 196} 197 198/* 199 * Receive Router Advertisement Message. 200 * 201 * Based on RFC 2461 202 * TODO: on-link bit on prefix information 203 * TODO: ND_RA_FLAG_{OTHER,MANAGED} processing 204 */ 205void 206nd6_ra_input(struct mbuf *m, int off, int icmp6len) 207{ 208 struct ifnet *ifp = m->m_pkthdr.rcvif; 209 struct nd_ifinfo *ndi = ND_IFINFO(ifp); 210 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 211 struct nd_router_advert *nd_ra; 212 struct in6_addr saddr6 = ip6->ip6_src; 213 int mcast = 0; 214 union nd_opts ndopts; 215 struct nd_defrouter *dr; 216 char ip6bufs[INET6_ADDRSTRLEN], ip6bufd[INET6_ADDRSTRLEN]; 217 218 /* 219 * We only accept RAs only when the per-interface flag 220 * ND6_IFF_ACCEPT_RTADV is on the receiving interface. 221 */ 222 if (!(ndi->flags & ND6_IFF_ACCEPT_RTADV)) 223 goto freeit; 224 225 if (ip6->ip6_hlim != 255) { 226 nd6log((LOG_ERR, 227 "nd6_ra_input: invalid hlim (%d) from %s to %s on %s\n", 228 ip6->ip6_hlim, ip6_sprintf(ip6bufs, &ip6->ip6_src), 229 ip6_sprintf(ip6bufd, &ip6->ip6_dst), if_name(ifp))); 230 goto bad; 231 } 232 233 if (!IN6_IS_ADDR_LINKLOCAL(&saddr6)) { 234 nd6log((LOG_ERR, 235 "nd6_ra_input: src %s is not link-local\n", 236 ip6_sprintf(ip6bufs, &saddr6))); 237 goto bad; 238 } 239 240#ifndef PULLDOWN_TEST 241 IP6_EXTHDR_CHECK(m, off, icmp6len,); 242 nd_ra = (struct nd_router_advert *)((caddr_t)ip6 + off); 243#else 244 IP6_EXTHDR_GET(nd_ra, struct nd_router_advert *, m, off, icmp6len); 245 if (nd_ra == NULL) { 246 ICMP6STAT_INC(icp6s_tooshort); 247 return; 248 } 249#endif 250 251 icmp6len -= sizeof(*nd_ra); 252 nd6_option_init(nd_ra + 1, icmp6len, &ndopts); 253 if (nd6_options(&ndopts) < 0) { 254 nd6log((LOG_INFO, 255 "nd6_ra_input: invalid ND option, ignored\n")); 256 /* nd6_options have incremented stats */ 257 goto freeit; 258 } 259 260 { 261 struct nd_defrouter dr0; 262 u_int32_t advreachable = nd_ra->nd_ra_reachable; 263 264 /* remember if this is a multicasted advertisement */ 265 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) 266 mcast = 1; 267 268 bzero(&dr0, sizeof(dr0)); 269 dr0.rtaddr = saddr6; 270 dr0.flags = nd_ra->nd_ra_flags_reserved; 271 /* 272 * Effectively-disable the route in the RA packet 273 * when ND6_IFF_NO_RADR on the receiving interface or 274 * ip6.forwarding=1. 275 */ 276 if (ndi->flags & ND6_IFF_NO_RADR || V_ip6_forwarding) 277 dr0.rtlifetime = 0; 278 else 279 dr0.rtlifetime = ntohs(nd_ra->nd_ra_router_lifetime); 280 dr0.expire = time_second + dr0.rtlifetime; 281 dr0.ifp = ifp; 282 /* unspecified or not? (RFC 2461 6.3.4) */ 283 if (advreachable) { 284 advreachable = ntohl(advreachable); 285 if (advreachable <= MAX_REACHABLE_TIME && 286 ndi->basereachable != advreachable) { 287 ndi->basereachable = advreachable; 288 ndi->reachable = ND_COMPUTE_RTIME(ndi->basereachable); 289 ndi->recalctm = V_nd6_recalc_reachtm_interval; /* reset */ 290 } 291 } 292 if (nd_ra->nd_ra_retransmit) 293 ndi->retrans = ntohl(nd_ra->nd_ra_retransmit); 294 if (nd_ra->nd_ra_curhoplimit) 295 ndi->chlim = nd_ra->nd_ra_curhoplimit; 296 dr = defrtrlist_update(&dr0); 297 } 298 299 /* 300 * prefix 301 */ 302 if (ndopts.nd_opts_pi) { 303 struct nd_opt_hdr *pt; 304 struct nd_opt_prefix_info *pi = NULL; 305 struct nd_prefixctl pr; 306 307 for (pt = (struct nd_opt_hdr *)ndopts.nd_opts_pi; 308 pt <= (struct nd_opt_hdr *)ndopts.nd_opts_pi_end; 309 pt = (struct nd_opt_hdr *)((caddr_t)pt + 310 (pt->nd_opt_len << 3))) { 311 if (pt->nd_opt_type != ND_OPT_PREFIX_INFORMATION) 312 continue; 313 pi = (struct nd_opt_prefix_info *)pt; 314 315 if (pi->nd_opt_pi_len != 4) { 316 nd6log((LOG_INFO, 317 "nd6_ra_input: invalid option " 318 "len %d for prefix information option, " 319 "ignored\n", pi->nd_opt_pi_len)); 320 continue; 321 } 322 323 if (128 < pi->nd_opt_pi_prefix_len) { 324 nd6log((LOG_INFO, 325 "nd6_ra_input: invalid prefix " 326 "len %d for prefix information option, " 327 "ignored\n", pi->nd_opt_pi_prefix_len)); 328 continue; 329 } 330 331 if (IN6_IS_ADDR_MULTICAST(&pi->nd_opt_pi_prefix) 332 || IN6_IS_ADDR_LINKLOCAL(&pi->nd_opt_pi_prefix)) { 333 nd6log((LOG_INFO, 334 "nd6_ra_input: invalid prefix " 335 "%s, ignored\n", 336 ip6_sprintf(ip6bufs, 337 &pi->nd_opt_pi_prefix))); 338 continue; 339 } 340 341 bzero(&pr, sizeof(pr)); 342 pr.ndpr_prefix.sin6_family = AF_INET6; 343 pr.ndpr_prefix.sin6_len = sizeof(pr.ndpr_prefix); 344 pr.ndpr_prefix.sin6_addr = pi->nd_opt_pi_prefix; 345 pr.ndpr_ifp = (struct ifnet *)m->m_pkthdr.rcvif; 346 347 pr.ndpr_raf_onlink = (pi->nd_opt_pi_flags_reserved & 348 ND_OPT_PI_FLAG_ONLINK) ? 1 : 0; 349 pr.ndpr_raf_auto = (pi->nd_opt_pi_flags_reserved & 350 ND_OPT_PI_FLAG_AUTO) ? 1 : 0; 351 pr.ndpr_plen = pi->nd_opt_pi_prefix_len; 352 pr.ndpr_vltime = ntohl(pi->nd_opt_pi_valid_time); 353 pr.ndpr_pltime = ntohl(pi->nd_opt_pi_preferred_time); 354 (void)prelist_update(&pr, dr, m, mcast); 355 } 356 } 357 358 /* 359 * MTU 360 */ 361 if (ndopts.nd_opts_mtu && ndopts.nd_opts_mtu->nd_opt_mtu_len == 1) { 362 u_long mtu; 363 u_long maxmtu; 364 365 mtu = (u_long)ntohl(ndopts.nd_opts_mtu->nd_opt_mtu_mtu); 366 367 /* lower bound */ 368 if (mtu < IPV6_MMTU) { 369 nd6log((LOG_INFO, "nd6_ra_input: bogus mtu option " 370 "mtu=%lu sent from %s, ignoring\n", 371 mtu, ip6_sprintf(ip6bufs, &ip6->ip6_src))); 372 goto skip; 373 } 374 375 /* upper bound */ 376 maxmtu = (ndi->maxmtu && ndi->maxmtu < ifp->if_mtu) 377 ? ndi->maxmtu : ifp->if_mtu; 378 if (mtu <= maxmtu) { 379 int change = (ndi->linkmtu != mtu); 380 381 ndi->linkmtu = mtu; 382 if (change) /* in6_maxmtu may change */ 383 in6_setmaxmtu(); 384 } else { 385 nd6log((LOG_INFO, "nd6_ra_input: bogus mtu " 386 "mtu=%lu sent from %s; " 387 "exceeds maxmtu %lu, ignoring\n", 388 mtu, ip6_sprintf(ip6bufs, &ip6->ip6_src), maxmtu)); 389 } 390 } 391 392 skip: 393 394 /* 395 * Source link layer address 396 */ 397 { 398 char *lladdr = NULL; 399 int lladdrlen = 0; 400 401 if (ndopts.nd_opts_src_lladdr) { 402 lladdr = (char *)(ndopts.nd_opts_src_lladdr + 1); 403 lladdrlen = ndopts.nd_opts_src_lladdr->nd_opt_len << 3; 404 } 405 406 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) { 407 nd6log((LOG_INFO, 408 "nd6_ra_input: lladdrlen mismatch for %s " 409 "(if %d, RA packet %d)\n", ip6_sprintf(ip6bufs, &saddr6), 410 ifp->if_addrlen, lladdrlen - 2)); 411 goto bad; 412 } 413 414 nd6_cache_lladdr(ifp, &saddr6, lladdr, 415 lladdrlen, ND_ROUTER_ADVERT, 0); 416 417 /* 418 * Installing a link-layer address might change the state of the 419 * router's neighbor cache, which might also affect our on-link 420 * detection of adveritsed prefixes. 421 */ 422 pfxlist_onlink_check(); 423 } 424 425 freeit: 426 m_freem(m); 427 return; 428 429 bad: 430 ICMP6STAT_INC(icp6s_badra); 431 m_freem(m); 432} 433 434/* 435 * default router list proccessing sub routines 436 */ 437 438/* tell the change to user processes watching the routing socket. */ 439static void 440nd6_rtmsg(int cmd, struct rtentry *rt) 441{ 442 struct rt_addrinfo info; 443 struct ifnet *ifp; 444 struct ifaddr *ifa; 445 446 bzero((caddr_t)&info, sizeof(info)); 447 info.rti_info[RTAX_DST] = rt_key(rt); 448 info.rti_info[RTAX_GATEWAY] = rt->rt_gateway; 449 info.rti_info[RTAX_NETMASK] = rt_mask(rt); 450 ifp = rt->rt_ifp; 451 if (ifp != NULL) { 452 IF_ADDR_LOCK(ifp); 453 ifa = TAILQ_FIRST(&ifp->if_addrhead); 454 info.rti_info[RTAX_IFP] = ifa->ifa_addr; 455 ifa_ref(ifa); 456 IF_ADDR_UNLOCK(ifp); 457 info.rti_info[RTAX_IFA] = rt->rt_ifa->ifa_addr; 458 } else 459 ifa = NULL; 460 461 rt_missmsg(cmd, &info, rt->rt_flags, 0); 462 if (ifa != NULL) 463 ifa_free(ifa); 464} 465 466void 467defrouter_addreq(struct nd_defrouter *new) 468{ 469 struct sockaddr_in6 def, mask, gate; 470 struct rtentry *newrt = NULL; 471 int s; 472 int error; 473 474 bzero(&def, sizeof(def)); 475 bzero(&mask, sizeof(mask)); 476 bzero(&gate, sizeof(gate)); 477 478 def.sin6_len = mask.sin6_len = gate.sin6_len = 479 sizeof(struct sockaddr_in6); 480 def.sin6_family = gate.sin6_family = AF_INET6; 481 gate.sin6_addr = new->rtaddr; 482 483 s = splnet(); 484 error = rtrequest(RTM_ADD, (struct sockaddr *)&def, 485 (struct sockaddr *)&gate, (struct sockaddr *)&mask, 486 RTF_GATEWAY, &newrt); 487 if (newrt) { 488 nd6_rtmsg(RTM_ADD, newrt); /* tell user process */ 489 RTFREE(newrt); 490 } 491 if (error == 0) 492 new->installed = 1; 493 splx(s); 494 return; 495} 496 497struct nd_defrouter * 498defrouter_lookup(struct in6_addr *addr, struct ifnet *ifp) 499{ 500 struct nd_defrouter *dr; 501 502 for (dr = TAILQ_FIRST(&V_nd_defrouter); dr; 503 dr = TAILQ_NEXT(dr, dr_entry)) { 504 if (dr->ifp == ifp && IN6_ARE_ADDR_EQUAL(addr, &dr->rtaddr)) 505 return (dr); 506 } 507 508 return (NULL); /* search failed */ 509} 510 511/* 512 * Remove the default route for a given router. 513 * This is just a subroutine function for defrouter_select(), and should 514 * not be called from anywhere else. 515 */ 516static void 517defrouter_delreq(struct nd_defrouter *dr) 518{ 519 struct sockaddr_in6 def, mask, gate; 520 struct rtentry *oldrt = NULL; 521 522 bzero(&def, sizeof(def)); 523 bzero(&mask, sizeof(mask)); 524 bzero(&gate, sizeof(gate)); 525 526 def.sin6_len = mask.sin6_len = gate.sin6_len = 527 sizeof(struct sockaddr_in6); 528 def.sin6_family = gate.sin6_family = AF_INET6; 529 gate.sin6_addr = dr->rtaddr; 530 531 rtrequest(RTM_DELETE, (struct sockaddr *)&def, 532 (struct sockaddr *)&gate, 533 (struct sockaddr *)&mask, RTF_GATEWAY, &oldrt); 534 if (oldrt) { 535 nd6_rtmsg(RTM_DELETE, oldrt); 536 RTFREE(oldrt); 537 } 538 539 dr->installed = 0; 540} 541 542/* 543 * remove all default routes from default router list 544 */ 545void 546defrouter_reset(void) 547{ 548 struct nd_defrouter *dr; 549 550 for (dr = TAILQ_FIRST(&V_nd_defrouter); dr; 551 dr = TAILQ_NEXT(dr, dr_entry)) 552 defrouter_delreq(dr); 553 554 /* 555 * XXX should we also nuke any default routers in the kernel, by 556 * going through them by rtalloc1()? 557 */ 558} 559 560void 561defrtrlist_del(struct nd_defrouter *dr) 562{ 563 struct nd_defrouter *deldr = NULL; 564 struct nd_prefix *pr; 565 566 /* 567 * Flush all the routing table entries that use the router 568 * as a next hop. 569 */ 570 if (ND_IFINFO(dr->ifp)->flags & ND6_IFF_ACCEPT_RTADV) 571 rt6_flush(&dr->rtaddr, dr->ifp); 572 573 if (dr->installed) { 574 deldr = dr; 575 defrouter_delreq(dr); 576 } 577 TAILQ_REMOVE(&V_nd_defrouter, dr, dr_entry); 578 579 /* 580 * Also delete all the pointers to the router in each prefix lists. 581 */ 582 for (pr = V_nd_prefix.lh_first; pr; pr = pr->ndpr_next) { 583 struct nd_pfxrouter *pfxrtr; 584 if ((pfxrtr = pfxrtr_lookup(pr, dr)) != NULL) 585 pfxrtr_del(pfxrtr); 586 } 587 pfxlist_onlink_check(); 588 589 /* 590 * If the router is the primary one, choose a new one. 591 * Note that defrouter_select() will remove the current gateway 592 * from the routing table. 593 */ 594 if (deldr) 595 defrouter_select(); 596 597 free(dr, M_IP6NDP); 598} 599 600/* 601 * Default Router Selection according to Section 6.3.6 of RFC 2461 and 602 * draft-ietf-ipngwg-router-selection: 603 * 1) Routers that are reachable or probably reachable should be preferred. 604 * If we have more than one (probably) reachable router, prefer ones 605 * with the highest router preference. 606 * 2) When no routers on the list are known to be reachable or 607 * probably reachable, routers SHOULD be selected in a round-robin 608 * fashion, regardless of router preference values. 609 * 3) If the Default Router List is empty, assume that all 610 * destinations are on-link. 611 * 612 * We assume nd_defrouter is sorted by router preference value. 613 * Since the code below covers both with and without router preference cases, 614 * we do not need to classify the cases by ifdef. 615 * 616 * At this moment, we do not try to install more than one default router, 617 * even when the multipath routing is available, because we're not sure about 618 * the benefits for stub hosts comparing to the risk of making the code 619 * complicated and the possibility of introducing bugs. 620 */ 621void 622defrouter_select(void) 623{ 624 int s = splnet(); 625 struct nd_defrouter *dr, *selected_dr = NULL, *installed_dr = NULL; 626 struct llentry *ln = NULL; 627 628 /* 629 * Let's handle easy case (3) first: 630 * If default router list is empty, there's nothing to be done. 631 */ 632 if (!TAILQ_FIRST(&V_nd_defrouter)) { 633 splx(s); 634 return; 635 } 636 637 /* 638 * Search for a (probably) reachable router from the list. 639 * We just pick up the first reachable one (if any), assuming that 640 * the ordering rule of the list described in defrtrlist_update(). 641 */ 642 for (dr = TAILQ_FIRST(&V_nd_defrouter); dr; 643 dr = TAILQ_NEXT(dr, dr_entry)) { 644 IF_AFDATA_LOCK(dr->ifp); 645 if (selected_dr == NULL && 646 (ln = nd6_lookup(&dr->rtaddr, 0, dr->ifp)) && 647 ND6_IS_LLINFO_PROBREACH(ln)) { 648 selected_dr = dr; 649 } 650 IF_AFDATA_UNLOCK(dr->ifp); 651 if (ln != NULL) { 652 LLE_RUNLOCK(ln); 653 ln = NULL; 654 } 655 656 if (dr->installed && installed_dr == NULL) 657 installed_dr = dr; 658 else if (dr->installed && installed_dr) { 659 /* this should not happen. warn for diagnosis. */ 660 log(LOG_ERR, "defrouter_select: more than one router" 661 " is installed\n"); 662 } 663 } 664 /* 665 * If none of the default routers was found to be reachable, 666 * round-robin the list regardless of preference. 667 * Otherwise, if we have an installed router, check if the selected 668 * (reachable) router should really be preferred to the installed one. 669 * We only prefer the new router when the old one is not reachable 670 * or when the new one has a really higher preference value. 671 */ 672 if (selected_dr == NULL) { 673 if (installed_dr == NULL || !TAILQ_NEXT(installed_dr, dr_entry)) 674 selected_dr = TAILQ_FIRST(&V_nd_defrouter); 675 else 676 selected_dr = TAILQ_NEXT(installed_dr, dr_entry); 677 } else if (installed_dr) { 678 IF_AFDATA_LOCK(installed_dr->ifp); 679 if ((ln = nd6_lookup(&installed_dr->rtaddr, 0, installed_dr->ifp)) && 680 ND6_IS_LLINFO_PROBREACH(ln) && 681 rtpref(selected_dr) <= rtpref(installed_dr)) { 682 selected_dr = installed_dr; 683 } 684 IF_AFDATA_UNLOCK(installed_dr->ifp); 685 if (ln != NULL) 686 LLE_RUNLOCK(ln); 687 } 688 689 /* 690 * If the selected router is different than the installed one, 691 * remove the installed router and install the selected one. 692 * Note that the selected router is never NULL here. 693 */ 694 if (installed_dr != selected_dr) { 695 if (installed_dr) 696 defrouter_delreq(installed_dr); 697 defrouter_addreq(selected_dr); 698 } 699 700 splx(s); 701 return; 702} 703 704/* 705 * for default router selection 706 * regards router-preference field as a 2-bit signed integer 707 */ 708static int 709rtpref(struct nd_defrouter *dr) 710{ 711 switch (dr->flags & ND_RA_FLAG_RTPREF_MASK) { 712 case ND_RA_FLAG_RTPREF_HIGH: 713 return (RTPREF_HIGH); 714 case ND_RA_FLAG_RTPREF_MEDIUM: 715 case ND_RA_FLAG_RTPREF_RSV: 716 return (RTPREF_MEDIUM); 717 case ND_RA_FLAG_RTPREF_LOW: 718 return (RTPREF_LOW); 719 default: 720 /* 721 * This case should never happen. If it did, it would mean a 722 * serious bug of kernel internal. We thus always bark here. 723 * Or, can we even panic? 724 */ 725 log(LOG_ERR, "rtpref: impossible RA flag %x\n", dr->flags); 726 return (RTPREF_INVALID); 727 } 728 /* NOTREACHED */ 729} 730 731static struct nd_defrouter * 732defrtrlist_update(struct nd_defrouter *new) 733{ 734 struct nd_defrouter *dr, *n; 735 int s = splnet(); 736 737 if ((dr = defrouter_lookup(&new->rtaddr, new->ifp)) != NULL) { 738 /* entry exists */ 739 if (new->rtlifetime == 0) { 740 defrtrlist_del(dr); 741 dr = NULL; 742 } else { 743 int oldpref = rtpref(dr); 744 745 /* override */ 746 dr->flags = new->flags; /* xxx flag check */ 747 dr->rtlifetime = new->rtlifetime; 748 dr->expire = new->expire; 749 750 /* 751 * If the preference does not change, there's no need 752 * to sort the entries. 753 */ 754 if (rtpref(new) == oldpref) { 755 splx(s); 756 return (dr); 757 } 758 759 /* 760 * preferred router may be changed, so relocate 761 * this router. 762 * XXX: calling TAILQ_REMOVE directly is a bad manner. 763 * However, since defrtrlist_del() has many side 764 * effects, we intentionally do so here. 765 * defrouter_select() below will handle routing 766 * changes later. 767 */ 768 TAILQ_REMOVE(&V_nd_defrouter, dr, dr_entry); 769 n = dr; 770 goto insert; 771 } 772 splx(s); 773 return (dr); 774 } 775 776 /* entry does not exist */ 777 if (new->rtlifetime == 0) { 778 splx(s); 779 return (NULL); 780 } 781 782 n = (struct nd_defrouter *)malloc(sizeof(*n), M_IP6NDP, M_NOWAIT); 783 if (n == NULL) { 784 splx(s); 785 return (NULL); 786 } 787 bzero(n, sizeof(*n)); 788 *n = *new; 789 790insert: 791 /* 792 * Insert the new router in the Default Router List; 793 * The Default Router List should be in the descending order 794 * of router-preferece. Routers with the same preference are 795 * sorted in the arriving time order. 796 */ 797 798 /* insert at the end of the group */ 799 for (dr = TAILQ_FIRST(&V_nd_defrouter); dr; 800 dr = TAILQ_NEXT(dr, dr_entry)) { 801 if (rtpref(n) > rtpref(dr)) 802 break; 803 } 804 if (dr) 805 TAILQ_INSERT_BEFORE(dr, n, dr_entry); 806 else 807 TAILQ_INSERT_TAIL(&V_nd_defrouter, n, dr_entry); 808 809 defrouter_select(); 810 811 splx(s); 812 813 return (n); 814} 815 816static struct nd_pfxrouter * 817pfxrtr_lookup(struct nd_prefix *pr, struct nd_defrouter *dr) 818{ 819 struct nd_pfxrouter *search; 820 821 for (search = pr->ndpr_advrtrs.lh_first; search; search = search->pfr_next) { 822 if (search->router == dr) 823 break; 824 } 825 826 return (search); 827} 828 829static void 830pfxrtr_add(struct nd_prefix *pr, struct nd_defrouter *dr) 831{ 832 struct nd_pfxrouter *new; 833 834 new = (struct nd_pfxrouter *)malloc(sizeof(*new), M_IP6NDP, M_NOWAIT); 835 if (new == NULL) 836 return; 837 bzero(new, sizeof(*new)); 838 new->router = dr; 839 840 LIST_INSERT_HEAD(&pr->ndpr_advrtrs, new, pfr_entry); 841 842 pfxlist_onlink_check(); 843} 844 845static void 846pfxrtr_del(struct nd_pfxrouter *pfr) 847{ 848 LIST_REMOVE(pfr, pfr_entry); 849 free(pfr, M_IP6NDP); 850} 851 852struct nd_prefix * 853nd6_prefix_lookup(struct nd_prefixctl *key) 854{ 855 struct nd_prefix *search; 856 857 for (search = V_nd_prefix.lh_first; 858 search; search = search->ndpr_next) { 859 if (key->ndpr_ifp == search->ndpr_ifp && 860 key->ndpr_plen == search->ndpr_plen && 861 in6_are_prefix_equal(&key->ndpr_prefix.sin6_addr, 862 &search->ndpr_prefix.sin6_addr, key->ndpr_plen)) { 863 break; 864 } 865 } 866 867 return (search); 868} 869 870int 871nd6_prelist_add(struct nd_prefixctl *pr, struct nd_defrouter *dr, 872 struct nd_prefix **newp) 873{ 874 struct nd_prefix *new = NULL; 875 int error = 0; 876 int i, s; 877 char ip6buf[INET6_ADDRSTRLEN]; 878 879 new = (struct nd_prefix *)malloc(sizeof(*new), M_IP6NDP, M_NOWAIT); 880 if (new == NULL) 881 return(ENOMEM); 882 bzero(new, sizeof(*new)); 883 new->ndpr_ifp = pr->ndpr_ifp; 884 new->ndpr_prefix = pr->ndpr_prefix; 885 new->ndpr_plen = pr->ndpr_plen; 886 new->ndpr_vltime = pr->ndpr_vltime; 887 new->ndpr_pltime = pr->ndpr_pltime; 888 new->ndpr_flags = pr->ndpr_flags; 889 if ((error = in6_init_prefix_ltimes(new)) != 0) { 890 free(new, M_IP6NDP); 891 return(error); 892 } 893 new->ndpr_lastupdate = time_second; 894 if (newp != NULL) 895 *newp = new; 896 897 /* initialization */ 898 LIST_INIT(&new->ndpr_advrtrs); 899 in6_prefixlen2mask(&new->ndpr_mask, new->ndpr_plen); 900 /* make prefix in the canonical form */ 901 for (i = 0; i < 4; i++) 902 new->ndpr_prefix.sin6_addr.s6_addr32[i] &= 903 new->ndpr_mask.s6_addr32[i]; 904 905 s = splnet(); 906 /* link ndpr_entry to nd_prefix list */ 907 LIST_INSERT_HEAD(&V_nd_prefix, new, ndpr_entry); 908 splx(s); 909 910 /* ND_OPT_PI_FLAG_ONLINK processing */ 911 if (new->ndpr_raf_onlink) { 912 int e; 913 914 if ((e = nd6_prefix_onlink(new)) != 0) { 915 nd6log((LOG_ERR, "nd6_prelist_add: failed to make " 916 "the prefix %s/%d on-link on %s (errno=%d)\n", 917 ip6_sprintf(ip6buf, &pr->ndpr_prefix.sin6_addr), 918 pr->ndpr_plen, if_name(pr->ndpr_ifp), e)); 919 /* proceed anyway. XXX: is it correct? */ 920 } 921 } 922 923 if (dr) 924 pfxrtr_add(new, dr); 925 926 return 0; 927} 928 929void 930prelist_remove(struct nd_prefix *pr) 931{ 932 struct nd_pfxrouter *pfr, *next; 933 int e, s; 934 char ip6buf[INET6_ADDRSTRLEN]; 935 936 /* make sure to invalidate the prefix until it is really freed. */ 937 pr->ndpr_vltime = 0; 938 pr->ndpr_pltime = 0; 939 940 /* 941 * Though these flags are now meaningless, we'd rather keep the value 942 * of pr->ndpr_raf_onlink and pr->ndpr_raf_auto not to confuse users 943 * when executing "ndp -p". 944 */ 945 946 if ((pr->ndpr_stateflags & NDPRF_ONLINK) != 0 && 947 (e = nd6_prefix_offlink(pr)) != 0) { 948 nd6log((LOG_ERR, "prelist_remove: failed to make %s/%d offlink " 949 "on %s, errno=%d\n", 950 ip6_sprintf(ip6buf, &pr->ndpr_prefix.sin6_addr), 951 pr->ndpr_plen, if_name(pr->ndpr_ifp), e)); 952 /* what should we do? */ 953 } 954 955 if (pr->ndpr_refcnt > 0) 956 return; /* notice here? */ 957 958 s = splnet(); 959 960 /* unlink ndpr_entry from nd_prefix list */ 961 LIST_REMOVE(pr, ndpr_entry); 962 963 /* free list of routers that adversed the prefix */ 964 for (pfr = pr->ndpr_advrtrs.lh_first; pfr; pfr = next) { 965 next = pfr->pfr_next; 966 967 free(pfr, M_IP6NDP); 968 } 969 splx(s); 970 971 free(pr, M_IP6NDP); 972 973 pfxlist_onlink_check(); 974} 975 976/* 977 * dr - may be NULL 978 */ 979 980static int 981prelist_update(struct nd_prefixctl *new, struct nd_defrouter *dr, 982 struct mbuf *m, int mcast) 983{ 984 struct in6_ifaddr *ia6 = NULL, *ia6_match = NULL; 985 struct ifaddr *ifa; 986 struct ifnet *ifp = new->ndpr_ifp; 987 struct nd_prefix *pr; 988 int s = splnet(); 989 int error = 0; 990 int newprefix = 0; 991 int auth; 992 struct in6_addrlifetime lt6_tmp; 993 char ip6buf[INET6_ADDRSTRLEN]; 994 995 auth = 0; 996 if (m) { 997 /* 998 * Authenticity for NA consists authentication for 999 * both IP header and IP datagrams, doesn't it ? 1000 */ 1001#if defined(M_AUTHIPHDR) && defined(M_AUTHIPDGM) 1002 auth = ((m->m_flags & M_AUTHIPHDR) && 1003 (m->m_flags & M_AUTHIPDGM)); 1004#endif 1005 } 1006 1007 if ((pr = nd6_prefix_lookup(new)) != NULL) { 1008 /* 1009 * nd6_prefix_lookup() ensures that pr and new have the same 1010 * prefix on a same interface. 1011 */ 1012 1013 /* 1014 * Update prefix information. Note that the on-link (L) bit 1015 * and the autonomous (A) bit should NOT be changed from 1 1016 * to 0. 1017 */ 1018 if (new->ndpr_raf_onlink == 1) 1019 pr->ndpr_raf_onlink = 1; 1020 if (new->ndpr_raf_auto == 1) 1021 pr->ndpr_raf_auto = 1; 1022 if (new->ndpr_raf_onlink) { 1023 pr->ndpr_vltime = new->ndpr_vltime; 1024 pr->ndpr_pltime = new->ndpr_pltime; 1025 (void)in6_init_prefix_ltimes(pr); /* XXX error case? */ 1026 pr->ndpr_lastupdate = time_second; 1027 } 1028 1029 if (new->ndpr_raf_onlink && 1030 (pr->ndpr_stateflags & NDPRF_ONLINK) == 0) { 1031 int e; 1032 1033 if ((e = nd6_prefix_onlink(pr)) != 0) { 1034 nd6log((LOG_ERR, 1035 "prelist_update: failed to make " 1036 "the prefix %s/%d on-link on %s " 1037 "(errno=%d)\n", 1038 ip6_sprintf(ip6buf, 1039 &pr->ndpr_prefix.sin6_addr), 1040 pr->ndpr_plen, if_name(pr->ndpr_ifp), e)); 1041 /* proceed anyway. XXX: is it correct? */ 1042 } 1043 } 1044 1045 if (dr && pfxrtr_lookup(pr, dr) == NULL) 1046 pfxrtr_add(pr, dr); 1047 } else { 1048 struct nd_prefix *newpr = NULL; 1049 1050 newprefix = 1; 1051 1052 if (new->ndpr_vltime == 0) 1053 goto end; 1054 if (new->ndpr_raf_onlink == 0 && new->ndpr_raf_auto == 0) 1055 goto end; 1056 1057 error = nd6_prelist_add(new, dr, &newpr); 1058 if (error != 0 || newpr == NULL) { 1059 nd6log((LOG_NOTICE, "prelist_update: " 1060 "nd6_prelist_add failed for %s/%d on %s " 1061 "errno=%d, returnpr=%p\n", 1062 ip6_sprintf(ip6buf, &new->ndpr_prefix.sin6_addr), 1063 new->ndpr_plen, if_name(new->ndpr_ifp), 1064 error, newpr)); 1065 goto end; /* we should just give up in this case. */ 1066 } 1067 1068 /* 1069 * XXX: from the ND point of view, we can ignore a prefix 1070 * with the on-link bit being zero. However, we need a 1071 * prefix structure for references from autoconfigured 1072 * addresses. Thus, we explicitly make sure that the prefix 1073 * itself expires now. 1074 */ 1075 if (newpr->ndpr_raf_onlink == 0) { 1076 newpr->ndpr_vltime = 0; 1077 newpr->ndpr_pltime = 0; 1078 in6_init_prefix_ltimes(newpr); 1079 } 1080 1081 pr = newpr; 1082 } 1083 1084 /* 1085 * Address autoconfiguration based on Section 5.5.3 of RFC 2462. 1086 * Note that pr must be non NULL at this point. 1087 */ 1088 1089 /* 5.5.3 (a). Ignore the prefix without the A bit set. */ 1090 if (!new->ndpr_raf_auto) 1091 goto end; 1092 1093 /* 1094 * 5.5.3 (b). the link-local prefix should have been ignored in 1095 * nd6_ra_input. 1096 */ 1097 1098 /* 5.5.3 (c). Consistency check on lifetimes: pltime <= vltime. */ 1099 if (new->ndpr_pltime > new->ndpr_vltime) { 1100 error = EINVAL; /* XXX: won't be used */ 1101 goto end; 1102 } 1103 1104 /* 1105 * 5.5.3 (d). If the prefix advertised is not equal to the prefix of 1106 * an address configured by stateless autoconfiguration already in the 1107 * list of addresses associated with the interface, and the Valid 1108 * Lifetime is not 0, form an address. We first check if we have 1109 * a matching prefix. 1110 * Note: we apply a clarification in rfc2462bis-02 here. We only 1111 * consider autoconfigured addresses while RFC2462 simply said 1112 * "address". 1113 */ 1114 IF_ADDR_LOCK(ifp); 1115 TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) { 1116 struct in6_ifaddr *ifa6; 1117 u_int32_t remaininglifetime; 1118 1119 if (ifa->ifa_addr->sa_family != AF_INET6) 1120 continue; 1121 1122 ifa6 = (struct in6_ifaddr *)ifa; 1123 1124 /* 1125 * We only consider autoconfigured addresses as per rfc2462bis. 1126 */ 1127 if (!(ifa6->ia6_flags & IN6_IFF_AUTOCONF)) 1128 continue; 1129 1130 /* 1131 * Spec is not clear here, but I believe we should concentrate 1132 * on unicast (i.e. not anycast) addresses. 1133 * XXX: other ia6_flags? detached or duplicated? 1134 */ 1135 if ((ifa6->ia6_flags & IN6_IFF_ANYCAST) != 0) 1136 continue; 1137 1138 /* 1139 * Ignore the address if it is not associated with a prefix 1140 * or is associated with a prefix that is different from this 1141 * one. (pr is never NULL here) 1142 */ 1143 if (ifa6->ia6_ndpr != pr) 1144 continue; 1145 1146 if (ia6_match == NULL) /* remember the first one */ 1147 ia6_match = ifa6; 1148 1149 /* 1150 * An already autoconfigured address matched. Now that we 1151 * are sure there is at least one matched address, we can 1152 * proceed to 5.5.3. (e): update the lifetimes according to the 1153 * "two hours" rule and the privacy extension. 1154 * We apply some clarifications in rfc2462bis: 1155 * - use remaininglifetime instead of storedlifetime as a 1156 * variable name 1157 * - remove the dead code in the "two-hour" rule 1158 */ 1159#define TWOHOUR (120*60) 1160 lt6_tmp = ifa6->ia6_lifetime; 1161 1162 if (lt6_tmp.ia6t_vltime == ND6_INFINITE_LIFETIME) 1163 remaininglifetime = ND6_INFINITE_LIFETIME; 1164 else if (time_second - ifa6->ia6_updatetime > 1165 lt6_tmp.ia6t_vltime) { 1166 /* 1167 * The case of "invalid" address. We should usually 1168 * not see this case. 1169 */ 1170 remaininglifetime = 0; 1171 } else 1172 remaininglifetime = lt6_tmp.ia6t_vltime - 1173 (time_second - ifa6->ia6_updatetime); 1174 1175 /* when not updating, keep the current stored lifetime. */ 1176 lt6_tmp.ia6t_vltime = remaininglifetime; 1177 1178 if (TWOHOUR < new->ndpr_vltime || 1179 remaininglifetime < new->ndpr_vltime) { 1180 lt6_tmp.ia6t_vltime = new->ndpr_vltime; 1181 } else if (remaininglifetime <= TWOHOUR) { 1182 if (auth) { 1183 lt6_tmp.ia6t_vltime = new->ndpr_vltime; 1184 } 1185 } else { 1186 /* 1187 * new->ndpr_vltime <= TWOHOUR && 1188 * TWOHOUR < remaininglifetime 1189 */ 1190 lt6_tmp.ia6t_vltime = TWOHOUR; 1191 } 1192 1193 /* The 2 hour rule is not imposed for preferred lifetime. */ 1194 lt6_tmp.ia6t_pltime = new->ndpr_pltime; 1195 1196 in6_init_address_ltimes(pr, <6_tmp); 1197 1198 /* 1199 * We need to treat lifetimes for temporary addresses 1200 * differently, according to 1201 * draft-ietf-ipv6-privacy-addrs-v2-01.txt 3.3 (1); 1202 * we only update the lifetimes when they are in the maximum 1203 * intervals. 1204 */ 1205 if ((ifa6->ia6_flags & IN6_IFF_TEMPORARY) != 0) { 1206 u_int32_t maxvltime, maxpltime; 1207 1208 if (V_ip6_temp_valid_lifetime > 1209 (u_int32_t)((time_second - ifa6->ia6_createtime) + 1210 V_ip6_desync_factor)) { 1211 maxvltime = V_ip6_temp_valid_lifetime - 1212 (time_second - ifa6->ia6_createtime) - 1213 V_ip6_desync_factor; 1214 } else 1215 maxvltime = 0; 1216 if (V_ip6_temp_preferred_lifetime > 1217 (u_int32_t)((time_second - ifa6->ia6_createtime) + 1218 V_ip6_desync_factor)) { 1219 maxpltime = V_ip6_temp_preferred_lifetime - 1220 (time_second - ifa6->ia6_createtime) - 1221 V_ip6_desync_factor; 1222 } else 1223 maxpltime = 0; 1224 1225 if (lt6_tmp.ia6t_vltime == ND6_INFINITE_LIFETIME || 1226 lt6_tmp.ia6t_vltime > maxvltime) { 1227 lt6_tmp.ia6t_vltime = maxvltime; 1228 } 1229 if (lt6_tmp.ia6t_pltime == ND6_INFINITE_LIFETIME || 1230 lt6_tmp.ia6t_pltime > maxpltime) { 1231 lt6_tmp.ia6t_pltime = maxpltime; 1232 } 1233 } 1234 ifa6->ia6_lifetime = lt6_tmp; 1235 ifa6->ia6_updatetime = time_second; 1236 } 1237 IF_ADDR_UNLOCK(ifp); 1238 if (ia6_match == NULL && new->ndpr_vltime) { 1239 int ifidlen; 1240 1241 /* 1242 * 5.5.3 (d) (continued) 1243 * No address matched and the valid lifetime is non-zero. 1244 * Create a new address. 1245 */ 1246 1247 /* 1248 * Prefix Length check: 1249 * If the sum of the prefix length and interface identifier 1250 * length does not equal 128 bits, the Prefix Information 1251 * option MUST be ignored. The length of the interface 1252 * identifier is defined in a separate link-type specific 1253 * document. 1254 */ 1255 ifidlen = in6_if2idlen(ifp); 1256 if (ifidlen < 0) { 1257 /* this should not happen, so we always log it. */ 1258 log(LOG_ERR, "prelist_update: IFID undefined (%s)\n", 1259 if_name(ifp)); 1260 goto end; 1261 } 1262 if (ifidlen + pr->ndpr_plen != 128) { 1263 nd6log((LOG_INFO, 1264 "prelist_update: invalid prefixlen " 1265 "%d for %s, ignored\n", 1266 pr->ndpr_plen, if_name(ifp))); 1267 goto end; 1268 } 1269 1270 if ((ia6 = in6_ifadd(new, mcast)) != NULL) { 1271 /* 1272 * note that we should use pr (not new) for reference. 1273 */ 1274 pr->ndpr_refcnt++; 1275 ia6->ia6_ndpr = pr; 1276 1277 /* 1278 * RFC 3041 3.3 (2). 1279 * When a new public address is created as described 1280 * in RFC2462, also create a new temporary address. 1281 * 1282 * RFC 3041 3.5. 1283 * When an interface connects to a new link, a new 1284 * randomized interface identifier should be generated 1285 * immediately together with a new set of temporary 1286 * addresses. Thus, we specifiy 1 as the 2nd arg of 1287 * in6_tmpifadd(). 1288 */ 1289 if (V_ip6_use_tempaddr) { 1290 int e; 1291 if ((e = in6_tmpifadd(ia6, 1, 1)) != 0) { 1292 nd6log((LOG_NOTICE, "prelist_update: " 1293 "failed to create a temporary " 1294 "address, errno=%d\n", 1295 e)); 1296 } 1297 } 1298 ifa_free(&ia6->ia_ifa); 1299 1300 /* 1301 * A newly added address might affect the status 1302 * of other addresses, so we check and update it. 1303 * XXX: what if address duplication happens? 1304 */ 1305 pfxlist_onlink_check(); 1306 } else { 1307 /* just set an error. do not bark here. */ 1308 error = EADDRNOTAVAIL; /* XXX: might be unused. */ 1309 } 1310 } 1311 1312 end: 1313 splx(s); 1314 return error; 1315} 1316 1317/* 1318 * A supplement function used in the on-link detection below; 1319 * detect if a given prefix has a (probably) reachable advertising router. 1320 * XXX: lengthy function name... 1321 */ 1322static struct nd_pfxrouter * 1323find_pfxlist_reachable_router(struct nd_prefix *pr) 1324{ 1325 struct nd_pfxrouter *pfxrtr; 1326 struct llentry *ln; 1327 int canreach; 1328 1329 for (pfxrtr = LIST_FIRST(&pr->ndpr_advrtrs); pfxrtr != NULL; 1330 pfxrtr = LIST_NEXT(pfxrtr, pfr_entry)) { 1331 IF_AFDATA_LOCK(pfxrtr->router->ifp); 1332 ln = nd6_lookup(&pfxrtr->router->rtaddr, 0, pfxrtr->router->ifp); 1333 IF_AFDATA_UNLOCK(pfxrtr->router->ifp); 1334 if (ln == NULL) 1335 continue; 1336 canreach = ND6_IS_LLINFO_PROBREACH(ln); 1337 LLE_RUNLOCK(ln); 1338 if (canreach) 1339 break; 1340 } 1341 return (pfxrtr); 1342} 1343 1344/* 1345 * Check if each prefix in the prefix list has at least one available router 1346 * that advertised the prefix (a router is "available" if its neighbor cache 1347 * entry is reachable or probably reachable). 1348 * If the check fails, the prefix may be off-link, because, for example, 1349 * we have moved from the network but the lifetime of the prefix has not 1350 * expired yet. So we should not use the prefix if there is another prefix 1351 * that has an available router. 1352 * But, if there is no prefix that has an available router, we still regards 1353 * all the prefixes as on-link. This is because we can't tell if all the 1354 * routers are simply dead or if we really moved from the network and there 1355 * is no router around us. 1356 */ 1357void 1358pfxlist_onlink_check() 1359{ 1360 struct nd_prefix *pr; 1361 struct in6_ifaddr *ifa; 1362 struct nd_defrouter *dr; 1363 struct nd_pfxrouter *pfxrtr = NULL; 1364 1365 /* 1366 * Check if there is a prefix that has a reachable advertising 1367 * router. 1368 */ 1369 for (pr = V_nd_prefix.lh_first; pr; pr = pr->ndpr_next) { 1370 if (pr->ndpr_raf_onlink && find_pfxlist_reachable_router(pr)) 1371 break; 1372 } 1373 1374 /* 1375 * If we have no such prefix, check whether we still have a router 1376 * that does not advertise any prefixes. 1377 */ 1378 if (pr == NULL) { 1379 for (dr = TAILQ_FIRST(&V_nd_defrouter); dr; 1380 dr = TAILQ_NEXT(dr, dr_entry)) { 1381 struct nd_prefix *pr0; 1382 1383 for (pr0 = V_nd_prefix.lh_first; pr0; 1384 pr0 = pr0->ndpr_next) { 1385 if ((pfxrtr = pfxrtr_lookup(pr0, dr)) != NULL) 1386 break; 1387 } 1388 if (pfxrtr != NULL) 1389 break; 1390 } 1391 } 1392 if (pr != NULL || (TAILQ_FIRST(&V_nd_defrouter) && pfxrtr == NULL)) { 1393 /* 1394 * There is at least one prefix that has a reachable router, 1395 * or at least a router which probably does not advertise 1396 * any prefixes. The latter would be the case when we move 1397 * to a new link where we have a router that does not provide 1398 * prefixes and we configure an address by hand. 1399 * Detach prefixes which have no reachable advertising 1400 * router, and attach other prefixes. 1401 */ 1402 for (pr = V_nd_prefix.lh_first; pr; pr = pr->ndpr_next) { 1403 /* XXX: a link-local prefix should never be detached */ 1404 if (IN6_IS_ADDR_LINKLOCAL(&pr->ndpr_prefix.sin6_addr)) 1405 continue; 1406 1407 /* 1408 * we aren't interested in prefixes without the L bit 1409 * set. 1410 */ 1411 if (pr->ndpr_raf_onlink == 0) 1412 continue; 1413 1414 if (pr->ndpr_raf_auto == 0) 1415 continue; 1416 1417 if ((pr->ndpr_stateflags & NDPRF_DETACHED) == 0 && 1418 find_pfxlist_reachable_router(pr) == NULL) 1419 pr->ndpr_stateflags |= NDPRF_DETACHED; 1420 if ((pr->ndpr_stateflags & NDPRF_DETACHED) != 0 && 1421 find_pfxlist_reachable_router(pr) != 0) 1422 pr->ndpr_stateflags &= ~NDPRF_DETACHED; 1423 } 1424 } else { 1425 /* there is no prefix that has a reachable router */ 1426 for (pr = V_nd_prefix.lh_first; pr; pr = pr->ndpr_next) { 1427 if (IN6_IS_ADDR_LINKLOCAL(&pr->ndpr_prefix.sin6_addr)) 1428 continue; 1429 1430 if (pr->ndpr_raf_onlink == 0) 1431 continue; 1432 1433 if (pr->ndpr_raf_auto == 0) 1434 continue; 1435 1436 if ((pr->ndpr_stateflags & NDPRF_DETACHED) != 0) 1437 pr->ndpr_stateflags &= ~NDPRF_DETACHED; 1438 } 1439 } 1440 1441 /* 1442 * Remove each interface route associated with a (just) detached 1443 * prefix, and reinstall the interface route for a (just) attached 1444 * prefix. Note that all attempt of reinstallation does not 1445 * necessarily success, when a same prefix is shared among multiple 1446 * interfaces. Such cases will be handled in nd6_prefix_onlink, 1447 * so we don't have to care about them. 1448 */ 1449 for (pr = V_nd_prefix.lh_first; pr; pr = pr->ndpr_next) { 1450 int e; 1451 char ip6buf[INET6_ADDRSTRLEN]; 1452 1453 if (IN6_IS_ADDR_LINKLOCAL(&pr->ndpr_prefix.sin6_addr)) 1454 continue; 1455 1456 if (pr->ndpr_raf_onlink == 0) 1457 continue; 1458 1459 if (pr->ndpr_raf_auto == 0) 1460 continue; 1461 1462 if ((pr->ndpr_stateflags & NDPRF_DETACHED) != 0 && 1463 (pr->ndpr_stateflags & NDPRF_ONLINK) != 0) { 1464 if ((e = nd6_prefix_offlink(pr)) != 0) { 1465 nd6log((LOG_ERR, 1466 "pfxlist_onlink_check: failed to " 1467 "make %s/%d offlink, errno=%d\n", 1468 ip6_sprintf(ip6buf, 1469 &pr->ndpr_prefix.sin6_addr), 1470 pr->ndpr_plen, e)); 1471 } 1472 } 1473 if ((pr->ndpr_stateflags & NDPRF_DETACHED) == 0 && 1474 (pr->ndpr_stateflags & NDPRF_ONLINK) == 0 && 1475 pr->ndpr_raf_onlink) { 1476 if ((e = nd6_prefix_onlink(pr)) != 0) { 1477 nd6log((LOG_ERR, 1478 "pfxlist_onlink_check: failed to " 1479 "make %s/%d onlink, errno=%d\n", 1480 ip6_sprintf(ip6buf, 1481 &pr->ndpr_prefix.sin6_addr), 1482 pr->ndpr_plen, e)); 1483 } 1484 } 1485 } 1486 1487 /* 1488 * Changes on the prefix status might affect address status as well. 1489 * Make sure that all addresses derived from an attached prefix are 1490 * attached, and that all addresses derived from a detached prefix are 1491 * detached. Note, however, that a manually configured address should 1492 * always be attached. 1493 * The precise detection logic is same as the one for prefixes. 1494 * 1495 * XXXRW: in6_ifaddrhead locking. 1496 */ 1497 TAILQ_FOREACH(ifa, &V_in6_ifaddrhead, ia_link) { 1498 if (!(ifa->ia6_flags & IN6_IFF_AUTOCONF)) 1499 continue; 1500 1501 if (ifa->ia6_ndpr == NULL) { 1502 /* 1503 * This can happen when we first configure the address 1504 * (i.e. the address exists, but the prefix does not). 1505 * XXX: complicated relationships... 1506 */ 1507 continue; 1508 } 1509 1510 if (find_pfxlist_reachable_router(ifa->ia6_ndpr)) 1511 break; 1512 } 1513 if (ifa) { 1514 TAILQ_FOREACH(ifa, &V_in6_ifaddrhead, ia_link) { 1515 if ((ifa->ia6_flags & IN6_IFF_AUTOCONF) == 0) 1516 continue; 1517 1518 if (ifa->ia6_ndpr == NULL) /* XXX: see above. */ 1519 continue; 1520 1521 if (find_pfxlist_reachable_router(ifa->ia6_ndpr)) { 1522 if (ifa->ia6_flags & IN6_IFF_DETACHED) { 1523 ifa->ia6_flags &= ~IN6_IFF_DETACHED; 1524 ifa->ia6_flags |= IN6_IFF_TENTATIVE; 1525 nd6_dad_start((struct ifaddr *)ifa, 0); 1526 } 1527 } else { 1528 ifa->ia6_flags |= IN6_IFF_DETACHED; 1529 } 1530 } 1531 } 1532 else { 1533 TAILQ_FOREACH(ifa, &V_in6_ifaddrhead, ia_link) { 1534 if ((ifa->ia6_flags & IN6_IFF_AUTOCONF) == 0) 1535 continue; 1536 1537 if (ifa->ia6_flags & IN6_IFF_DETACHED) { 1538 ifa->ia6_flags &= ~IN6_IFF_DETACHED; 1539 ifa->ia6_flags |= IN6_IFF_TENTATIVE; 1540 /* Do we need a delay in this case? */ 1541 nd6_dad_start((struct ifaddr *)ifa, 0); 1542 } 1543 } 1544 } 1545} 1546 1547int 1548nd6_prefix_onlink(struct nd_prefix *pr) 1549{ 1550 struct ifaddr *ifa; 1551 struct ifnet *ifp = pr->ndpr_ifp; 1552 struct sockaddr_in6 mask6; 1553 struct nd_prefix *opr; 1554 u_long rtflags; 1555 int error = 0; 1556 struct radix_node_head *rnh; 1557 struct rtentry *rt = NULL; 1558 char ip6buf[INET6_ADDRSTRLEN]; 1559 struct sockaddr_dl null_sdl = {sizeof(null_sdl), AF_LINK}; 1560 1561 /* sanity check */ 1562 if ((pr->ndpr_stateflags & NDPRF_ONLINK) != 0) { 1563 nd6log((LOG_ERR, 1564 "nd6_prefix_onlink: %s/%d is already on-link\n", 1565 ip6_sprintf(ip6buf, &pr->ndpr_prefix.sin6_addr), 1566 pr->ndpr_plen)); 1567 return (EEXIST); 1568 } 1569 1570 /* 1571 * Add the interface route associated with the prefix. Before 1572 * installing the route, check if there's the same prefix on another 1573 * interface, and the prefix has already installed the interface route. 1574 * Although such a configuration is expected to be rare, we explicitly 1575 * allow it. 1576 */ 1577 for (opr = V_nd_prefix.lh_first; opr; opr = opr->ndpr_next) { 1578 if (opr == pr) 1579 continue; 1580 1581 if ((opr->ndpr_stateflags & NDPRF_ONLINK) == 0) 1582 continue; 1583 1584 if (opr->ndpr_plen == pr->ndpr_plen && 1585 in6_are_prefix_equal(&pr->ndpr_prefix.sin6_addr, 1586 &opr->ndpr_prefix.sin6_addr, pr->ndpr_plen)) 1587 return (0); 1588 } 1589 1590 /* 1591 * We prefer link-local addresses as the associated interface address. 1592 */ 1593 /* search for a link-local addr */ 1594 ifa = (struct ifaddr *)in6ifa_ifpforlinklocal(ifp, 1595 IN6_IFF_NOTREADY | IN6_IFF_ANYCAST); 1596 if (ifa == NULL) { 1597 /* XXX: freebsd does not have ifa_ifwithaf */ 1598 IF_ADDR_LOCK(ifp); 1599 TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) { 1600 if (ifa->ifa_addr->sa_family == AF_INET6) 1601 break; 1602 } 1603 if (ifa != NULL) 1604 ifa_ref(ifa); 1605 IF_ADDR_UNLOCK(ifp); 1606 /* should we care about ia6_flags? */ 1607 } 1608 if (ifa == NULL) { 1609 /* 1610 * This can still happen, when, for example, we receive an RA 1611 * containing a prefix with the L bit set and the A bit clear, 1612 * after removing all IPv6 addresses on the receiving 1613 * interface. This should, of course, be rare though. 1614 */ 1615 nd6log((LOG_NOTICE, 1616 "nd6_prefix_onlink: failed to find any ifaddr" 1617 " to add route for a prefix(%s/%d) on %s\n", 1618 ip6_sprintf(ip6buf, &pr->ndpr_prefix.sin6_addr), 1619 pr->ndpr_plen, if_name(ifp))); 1620 return (0); 1621 } 1622 1623 /* 1624 * in6_ifinit() sets nd6_rtrequest to ifa_rtrequest for all ifaddrs. 1625 * ifa->ifa_rtrequest = nd6_rtrequest; 1626 */ 1627 bzero(&mask6, sizeof(mask6)); 1628 mask6.sin6_len = sizeof(mask6); 1629 mask6.sin6_addr = pr->ndpr_mask; 1630 rtflags = (ifa->ifa_flags & ~IFA_RTSELF) | RTF_UP; 1631 error = rtrequest(RTM_ADD, (struct sockaddr *)&pr->ndpr_prefix, 1632 ifa->ifa_addr, (struct sockaddr *)&mask6, rtflags, &rt); 1633 if (error == 0) { 1634 if (rt != NULL) /* this should be non NULL, though */ { 1635 rnh = rt_tables_get_rnh(rt->rt_fibnum, AF_INET6); 1636 /* XXX what if rhn == NULL? */ 1637 RADIX_NODE_HEAD_LOCK(rnh); 1638 RT_LOCK(rt); 1639 if (!rt_setgate(rt, rt_key(rt), (struct sockaddr *)&null_sdl)) { 1640 ((struct sockaddr_dl *)rt->rt_gateway)->sdl_type = 1641 rt->rt_ifp->if_type; 1642 ((struct sockaddr_dl *)rt->rt_gateway)->sdl_index = 1643 rt->rt_ifp->if_index; 1644 } 1645 RADIX_NODE_HEAD_UNLOCK(rnh); 1646 nd6_rtmsg(RTM_ADD, rt); 1647 RT_UNLOCK(rt); 1648 } 1649 pr->ndpr_stateflags |= NDPRF_ONLINK; 1650 } else { 1651 char ip6bufg[INET6_ADDRSTRLEN], ip6bufm[INET6_ADDRSTRLEN]; 1652 nd6log((LOG_ERR, "nd6_prefix_onlink: failed to add route for a" 1653 " prefix (%s/%d) on %s, gw=%s, mask=%s, flags=%lx " 1654 "errno = %d\n", 1655 ip6_sprintf(ip6buf, &pr->ndpr_prefix.sin6_addr), 1656 pr->ndpr_plen, if_name(ifp), 1657 ip6_sprintf(ip6bufg, &((struct sockaddr_in6 *)ifa->ifa_addr)->sin6_addr), 1658 ip6_sprintf(ip6bufm, &mask6.sin6_addr), rtflags, error)); 1659 } 1660 1661 if (rt != NULL) { 1662 RT_LOCK(rt); 1663 RT_REMREF(rt); 1664 RT_UNLOCK(rt); 1665 } 1666 if (ifa != NULL) 1667 ifa_free(ifa); 1668 1669 return (error); 1670} 1671 1672int 1673nd6_prefix_offlink(struct nd_prefix *pr) 1674{ 1675 int error = 0; 1676 struct ifnet *ifp = pr->ndpr_ifp; 1677 struct nd_prefix *opr; 1678 struct sockaddr_in6 sa6, mask6; 1679 struct rtentry *rt = NULL; 1680 char ip6buf[INET6_ADDRSTRLEN]; 1681 1682 /* sanity check */ 1683 if ((pr->ndpr_stateflags & NDPRF_ONLINK) == 0) { 1684 nd6log((LOG_ERR, 1685 "nd6_prefix_offlink: %s/%d is already off-link\n", 1686 ip6_sprintf(ip6buf, &pr->ndpr_prefix.sin6_addr), 1687 pr->ndpr_plen)); 1688 return (EEXIST); 1689 } 1690 1691 bzero(&sa6, sizeof(sa6)); 1692 sa6.sin6_family = AF_INET6; 1693 sa6.sin6_len = sizeof(sa6); 1694 bcopy(&pr->ndpr_prefix.sin6_addr, &sa6.sin6_addr, 1695 sizeof(struct in6_addr)); 1696 bzero(&mask6, sizeof(mask6)); 1697 mask6.sin6_family = AF_INET6; 1698 mask6.sin6_len = sizeof(sa6); 1699 bcopy(&pr->ndpr_mask, &mask6.sin6_addr, sizeof(struct in6_addr)); 1700 error = rtrequest(RTM_DELETE, (struct sockaddr *)&sa6, NULL, 1701 (struct sockaddr *)&mask6, 0, &rt); 1702 if (error == 0) { 1703 pr->ndpr_stateflags &= ~NDPRF_ONLINK; 1704 1705 /* report the route deletion to the routing socket. */ 1706 if (rt != NULL) 1707 nd6_rtmsg(RTM_DELETE, rt); 1708 1709 /* 1710 * There might be the same prefix on another interface, 1711 * the prefix which could not be on-link just because we have 1712 * the interface route (see comments in nd6_prefix_onlink). 1713 * If there's one, try to make the prefix on-link on the 1714 * interface. 1715 */ 1716 for (opr = V_nd_prefix.lh_first; opr; opr = opr->ndpr_next) { 1717 if (opr == pr) 1718 continue; 1719 1720 if ((opr->ndpr_stateflags & NDPRF_ONLINK) != 0) 1721 continue; 1722 1723 /* 1724 * KAME specific: detached prefixes should not be 1725 * on-link. 1726 */ 1727 if ((opr->ndpr_stateflags & NDPRF_DETACHED) != 0) 1728 continue; 1729 1730 if (opr->ndpr_plen == pr->ndpr_plen && 1731 in6_are_prefix_equal(&pr->ndpr_prefix.sin6_addr, 1732 &opr->ndpr_prefix.sin6_addr, pr->ndpr_plen)) { 1733 int e; 1734 1735 if ((e = nd6_prefix_onlink(opr)) != 0) { 1736 nd6log((LOG_ERR, 1737 "nd6_prefix_offlink: failed to " 1738 "recover a prefix %s/%d from %s " 1739 "to %s (errno = %d)\n", 1740 ip6_sprintf(ip6buf, 1741 &opr->ndpr_prefix.sin6_addr), 1742 opr->ndpr_plen, if_name(ifp), 1743 if_name(opr->ndpr_ifp), e)); 1744 } 1745 } 1746 } 1747 } else { 1748 /* XXX: can we still set the NDPRF_ONLINK flag? */ 1749 nd6log((LOG_ERR, 1750 "nd6_prefix_offlink: failed to delete route: " 1751 "%s/%d on %s (errno = %d)\n", 1752 ip6_sprintf(ip6buf, &sa6.sin6_addr), pr->ndpr_plen, 1753 if_name(ifp), error)); 1754 } 1755 1756 if (rt != NULL) { 1757 RTFREE(rt); 1758 } 1759 1760 return (error); 1761} 1762 1763static struct in6_ifaddr * 1764in6_ifadd(struct nd_prefixctl *pr, int mcast) 1765{ 1766 struct ifnet *ifp = pr->ndpr_ifp; 1767 struct ifaddr *ifa; 1768 struct in6_aliasreq ifra; 1769 struct in6_ifaddr *ia, *ib; 1770 int error, plen0; 1771 struct in6_addr mask; 1772 int prefixlen = pr->ndpr_plen; 1773 int updateflags; 1774 char ip6buf[INET6_ADDRSTRLEN]; 1775 1776 in6_prefixlen2mask(&mask, prefixlen); 1777 1778 /* 1779 * find a link-local address (will be interface ID). 1780 * Is it really mandatory? Theoretically, a global or a site-local 1781 * address can be configured without a link-local address, if we 1782 * have a unique interface identifier... 1783 * 1784 * it is not mandatory to have a link-local address, we can generate 1785 * interface identifier on the fly. we do this because: 1786 * (1) it should be the easiest way to find interface identifier. 1787 * (2) RFC2462 5.4 suggesting the use of the same interface identifier 1788 * for multiple addresses on a single interface, and possible shortcut 1789 * of DAD. we omitted DAD for this reason in the past. 1790 * (3) a user can prevent autoconfiguration of global address 1791 * by removing link-local address by hand (this is partly because we 1792 * don't have other way to control the use of IPv6 on an interface. 1793 * this has been our design choice - cf. NRL's "ifconfig auto"). 1794 * (4) it is easier to manage when an interface has addresses 1795 * with the same interface identifier, than to have multiple addresses 1796 * with different interface identifiers. 1797 */ 1798 ifa = (struct ifaddr *)in6ifa_ifpforlinklocal(ifp, 0); /* 0 is OK? */ 1799 if (ifa) 1800 ib = (struct in6_ifaddr *)ifa; 1801 else 1802 return NULL; 1803 1804 /* prefixlen + ifidlen must be equal to 128 */ 1805 plen0 = in6_mask2len(&ib->ia_prefixmask.sin6_addr, NULL); 1806 if (prefixlen != plen0) { 1807 ifa_free(ifa); 1808 nd6log((LOG_INFO, "in6_ifadd: wrong prefixlen for %s " 1809 "(prefix=%d ifid=%d)\n", 1810 if_name(ifp), prefixlen, 128 - plen0)); 1811 return NULL; 1812 } 1813 1814 /* make ifaddr */ 1815 1816 bzero(&ifra, sizeof(ifra)); 1817 /* 1818 * in6_update_ifa() does not use ifra_name, but we accurately set it 1819 * for safety. 1820 */ 1821 strncpy(ifra.ifra_name, if_name(ifp), sizeof(ifra.ifra_name)); 1822 ifra.ifra_addr.sin6_family = AF_INET6; 1823 ifra.ifra_addr.sin6_len = sizeof(struct sockaddr_in6); 1824 /* prefix */ 1825 ifra.ifra_addr.sin6_addr = pr->ndpr_prefix.sin6_addr; 1826 ifra.ifra_addr.sin6_addr.s6_addr32[0] &= mask.s6_addr32[0]; 1827 ifra.ifra_addr.sin6_addr.s6_addr32[1] &= mask.s6_addr32[1]; 1828 ifra.ifra_addr.sin6_addr.s6_addr32[2] &= mask.s6_addr32[2]; 1829 ifra.ifra_addr.sin6_addr.s6_addr32[3] &= mask.s6_addr32[3]; 1830 1831 /* interface ID */ 1832 ifra.ifra_addr.sin6_addr.s6_addr32[0] |= 1833 (ib->ia_addr.sin6_addr.s6_addr32[0] & ~mask.s6_addr32[0]); 1834 ifra.ifra_addr.sin6_addr.s6_addr32[1] |= 1835 (ib->ia_addr.sin6_addr.s6_addr32[1] & ~mask.s6_addr32[1]); 1836 ifra.ifra_addr.sin6_addr.s6_addr32[2] |= 1837 (ib->ia_addr.sin6_addr.s6_addr32[2] & ~mask.s6_addr32[2]); 1838 ifra.ifra_addr.sin6_addr.s6_addr32[3] |= 1839 (ib->ia_addr.sin6_addr.s6_addr32[3] & ~mask.s6_addr32[3]); 1840 ifa_free(ifa); 1841 1842 /* new prefix mask. */ 1843 ifra.ifra_prefixmask.sin6_len = sizeof(struct sockaddr_in6); 1844 ifra.ifra_prefixmask.sin6_family = AF_INET6; 1845 bcopy(&mask, &ifra.ifra_prefixmask.sin6_addr, 1846 sizeof(ifra.ifra_prefixmask.sin6_addr)); 1847 1848 /* lifetimes. */ 1849 ifra.ifra_lifetime.ia6t_vltime = pr->ndpr_vltime; 1850 ifra.ifra_lifetime.ia6t_pltime = pr->ndpr_pltime; 1851 1852 /* XXX: scope zone ID? */ 1853 1854 ifra.ifra_flags |= IN6_IFF_AUTOCONF; /* obey autoconf */ 1855 1856 /* 1857 * Make sure that we do not have this address already. This should 1858 * usually not happen, but we can still see this case, e.g., if we 1859 * have manually configured the exact address to be configured. 1860 */ 1861 ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, 1862 &ifra.ifra_addr.sin6_addr); 1863 if (ifa != NULL) { 1864 ifa_free(ifa); 1865 /* this should be rare enough to make an explicit log */ 1866 log(LOG_INFO, "in6_ifadd: %s is already configured\n", 1867 ip6_sprintf(ip6buf, &ifra.ifra_addr.sin6_addr)); 1868 return (NULL); 1869 } 1870 1871 /* 1872 * Allocate ifaddr structure, link into chain, etc. 1873 * If we are going to create a new address upon receiving a multicasted 1874 * RA, we need to impose a random delay before starting DAD. 1875 * [draft-ietf-ipv6-rfc2462bis-02.txt, Section 5.4.2] 1876 */ 1877 updateflags = 0; 1878 if (mcast) 1879 updateflags |= IN6_IFAUPDATE_DADDELAY; 1880 if ((error = in6_update_ifa(ifp, &ifra, NULL, updateflags)) != 0) { 1881 nd6log((LOG_ERR, 1882 "in6_ifadd: failed to make ifaddr %s on %s (errno=%d)\n", 1883 ip6_sprintf(ip6buf, &ifra.ifra_addr.sin6_addr), 1884 if_name(ifp), error)); 1885 return (NULL); /* ifaddr must not have been allocated. */ 1886 } 1887 1888 ia = in6ifa_ifpwithaddr(ifp, &ifra.ifra_addr.sin6_addr); 1889 /* 1890 * XXXRW: Assumption of non-NULLness here might not be true with 1891 * fine-grained locking -- should we validate it? Or just return 1892 * earlier ifa rather than looking it up again? 1893 */ 1894 return (ia); /* this is always non-NULL and referenced. */ 1895} 1896 1897/* 1898 * ia0 - corresponding public address 1899 */ 1900int 1901in6_tmpifadd(const struct in6_ifaddr *ia0, int forcegen, int delay) 1902{ 1903 struct ifnet *ifp = ia0->ia_ifa.ifa_ifp; 1904 struct in6_ifaddr *newia, *ia; 1905 struct in6_aliasreq ifra; 1906 int i, error; 1907 int trylimit = 3; /* XXX: adhoc value */ 1908 int updateflags; 1909 u_int32_t randid[2]; 1910 time_t vltime0, pltime0; 1911 1912 bzero(&ifra, sizeof(ifra)); 1913 strncpy(ifra.ifra_name, if_name(ifp), sizeof(ifra.ifra_name)); 1914 ifra.ifra_addr = ia0->ia_addr; 1915 /* copy prefix mask */ 1916 ifra.ifra_prefixmask = ia0->ia_prefixmask; 1917 /* clear the old IFID */ 1918 for (i = 0; i < 4; i++) { 1919 ifra.ifra_addr.sin6_addr.s6_addr32[i] &= 1920 ifra.ifra_prefixmask.sin6_addr.s6_addr32[i]; 1921 } 1922 1923 again: 1924 if (in6_get_tmpifid(ifp, (u_int8_t *)randid, 1925 (const u_int8_t *)&ia0->ia_addr.sin6_addr.s6_addr[8], forcegen)) { 1926 nd6log((LOG_NOTICE, "in6_tmpifadd: failed to find a good " 1927 "random IFID\n")); 1928 return (EINVAL); 1929 } 1930 ifra.ifra_addr.sin6_addr.s6_addr32[2] |= 1931 (randid[0] & ~(ifra.ifra_prefixmask.sin6_addr.s6_addr32[2])); 1932 ifra.ifra_addr.sin6_addr.s6_addr32[3] |= 1933 (randid[1] & ~(ifra.ifra_prefixmask.sin6_addr.s6_addr32[3])); 1934 1935 /* 1936 * in6_get_tmpifid() quite likely provided a unique interface ID. 1937 * However, we may still have a chance to see collision, because 1938 * there may be a time lag between generation of the ID and generation 1939 * of the address. So, we'll do one more sanity check. 1940 */ 1941 IN6_IFADDR_RLOCK(); 1942 TAILQ_FOREACH(ia, &V_in6_ifaddrhead, ia_link) { 1943 if (IN6_ARE_ADDR_EQUAL(&ia->ia_addr.sin6_addr, 1944 &ifra.ifra_addr.sin6_addr)) { 1945 if (trylimit-- == 0) { 1946 IN6_IFADDR_RUNLOCK(); 1947 /* 1948 * Give up. Something strange should have 1949 * happened. 1950 */ 1951 nd6log((LOG_NOTICE, "in6_tmpifadd: failed to " 1952 "find a unique random IFID\n")); 1953 return (EEXIST); 1954 } 1955 IN6_IFADDR_RUNLOCK(); 1956 forcegen = 1; 1957 goto again; 1958 } 1959 } 1960 IN6_IFADDR_RUNLOCK(); 1961 1962 /* 1963 * The Valid Lifetime is the lower of the Valid Lifetime of the 1964 * public address or TEMP_VALID_LIFETIME. 1965 * The Preferred Lifetime is the lower of the Preferred Lifetime 1966 * of the public address or TEMP_PREFERRED_LIFETIME - 1967 * DESYNC_FACTOR. 1968 */ 1969 if (ia0->ia6_lifetime.ia6t_vltime != ND6_INFINITE_LIFETIME) { 1970 vltime0 = IFA6_IS_INVALID(ia0) ? 0 : 1971 (ia0->ia6_lifetime.ia6t_vltime - 1972 (time_second - ia0->ia6_updatetime)); 1973 if (vltime0 > V_ip6_temp_valid_lifetime) 1974 vltime0 = V_ip6_temp_valid_lifetime; 1975 } else 1976 vltime0 = V_ip6_temp_valid_lifetime; 1977 if (ia0->ia6_lifetime.ia6t_pltime != ND6_INFINITE_LIFETIME) { 1978 pltime0 = IFA6_IS_DEPRECATED(ia0) ? 0 : 1979 (ia0->ia6_lifetime.ia6t_pltime - 1980 (time_second - ia0->ia6_updatetime)); 1981 if (pltime0 > V_ip6_temp_preferred_lifetime - V_ip6_desync_factor){ 1982 pltime0 = V_ip6_temp_preferred_lifetime - 1983 V_ip6_desync_factor; 1984 } 1985 } else 1986 pltime0 = V_ip6_temp_preferred_lifetime - V_ip6_desync_factor; 1987 ifra.ifra_lifetime.ia6t_vltime = vltime0; 1988 ifra.ifra_lifetime.ia6t_pltime = pltime0; 1989 1990 /* 1991 * A temporary address is created only if this calculated Preferred 1992 * Lifetime is greater than REGEN_ADVANCE time units. 1993 */ 1994 if (ifra.ifra_lifetime.ia6t_pltime <= V_ip6_temp_regen_advance) 1995 return (0); 1996 1997 /* XXX: scope zone ID? */ 1998 1999 ifra.ifra_flags |= (IN6_IFF_AUTOCONF|IN6_IFF_TEMPORARY); 2000 2001 /* allocate ifaddr structure, link into chain, etc. */ 2002 updateflags = 0; 2003 if (delay) 2004 updateflags |= IN6_IFAUPDATE_DADDELAY; 2005 if ((error = in6_update_ifa(ifp, &ifra, NULL, updateflags)) != 0) 2006 return (error); 2007 2008 newia = in6ifa_ifpwithaddr(ifp, &ifra.ifra_addr.sin6_addr); 2009 if (newia == NULL) { /* XXX: can it happen? */ 2010 nd6log((LOG_ERR, 2011 "in6_tmpifadd: ifa update succeeded, but we got " 2012 "no ifaddr\n")); 2013 return (EINVAL); /* XXX */ 2014 } 2015 newia->ia6_ndpr = ia0->ia6_ndpr; 2016 newia->ia6_ndpr->ndpr_refcnt++; 2017 ifa_free(&newia->ia_ifa); 2018 2019 /* 2020 * A newly added address might affect the status of other addresses. 2021 * XXX: when the temporary address is generated with a new public 2022 * address, the onlink check is redundant. However, it would be safe 2023 * to do the check explicitly everywhere a new address is generated, 2024 * and, in fact, we surely need the check when we create a new 2025 * temporary address due to deprecation of an old temporary address. 2026 */ 2027 pfxlist_onlink_check(); 2028 2029 return (0); 2030} 2031 2032static int 2033in6_init_prefix_ltimes(struct nd_prefix *ndpr) 2034{ 2035 if (ndpr->ndpr_pltime == ND6_INFINITE_LIFETIME) 2036 ndpr->ndpr_preferred = 0; 2037 else 2038 ndpr->ndpr_preferred = time_second + ndpr->ndpr_pltime; 2039 if (ndpr->ndpr_vltime == ND6_INFINITE_LIFETIME) 2040 ndpr->ndpr_expire = 0; 2041 else 2042 ndpr->ndpr_expire = time_second + ndpr->ndpr_vltime; 2043 2044 return 0; 2045} 2046 2047static void 2048in6_init_address_ltimes(struct nd_prefix *new, struct in6_addrlifetime *lt6) 2049{ 2050 /* init ia6t_expire */ 2051 if (lt6->ia6t_vltime == ND6_INFINITE_LIFETIME) 2052 lt6->ia6t_expire = 0; 2053 else { 2054 lt6->ia6t_expire = time_second; 2055 lt6->ia6t_expire += lt6->ia6t_vltime; 2056 } 2057 2058 /* init ia6t_preferred */ 2059 if (lt6->ia6t_pltime == ND6_INFINITE_LIFETIME) 2060 lt6->ia6t_preferred = 0; 2061 else { 2062 lt6->ia6t_preferred = time_second; 2063 lt6->ia6t_preferred += lt6->ia6t_pltime; 2064 } 2065} 2066 2067/* 2068 * Delete all the routing table entries that use the specified gateway. 2069 * XXX: this function causes search through all entries of routing table, so 2070 * it shouldn't be called when acting as a router. 2071 */ 2072void 2073rt6_flush(struct in6_addr *gateway, struct ifnet *ifp) 2074{ 2075 struct radix_node_head *rnh; 2076 int s = splnet(); 2077 2078 /* We'll care only link-local addresses */ 2079 if (!IN6_IS_ADDR_LINKLOCAL(gateway)) { 2080 splx(s); 2081 return; 2082 } 2083 2084 rnh = rt_tables_get_rnh(0, AF_INET6); 2085 if (rnh == NULL) 2086 return; 2087 2088 RADIX_NODE_HEAD_LOCK(rnh); 2089 rnh->rnh_walktree(rnh, rt6_deleteroute, (void *)gateway); 2090 RADIX_NODE_HEAD_UNLOCK(rnh); 2091 splx(s); 2092} 2093 2094static int 2095rt6_deleteroute(struct radix_node *rn, void *arg) 2096{ 2097#define SIN6(s) ((struct sockaddr_in6 *)s) 2098 struct rtentry *rt = (struct rtentry *)rn; 2099 struct in6_addr *gate = (struct in6_addr *)arg; 2100 2101 if (rt->rt_gateway == NULL || rt->rt_gateway->sa_family != AF_INET6) 2102 return (0); 2103 2104 if (!IN6_ARE_ADDR_EQUAL(gate, &SIN6(rt->rt_gateway)->sin6_addr)) { 2105 return (0); 2106 } 2107 2108 /* 2109 * Do not delete a static route. 2110 * XXX: this seems to be a bit ad-hoc. Should we consider the 2111 * 'cloned' bit instead? 2112 */ 2113 if ((rt->rt_flags & RTF_STATIC) != 0) 2114 return (0); 2115 2116 /* 2117 * We delete only host route. This means, in particular, we don't 2118 * delete default route. 2119 */ 2120 if ((rt->rt_flags & RTF_HOST) == 0) 2121 return (0); 2122 2123 return (rtrequest(RTM_DELETE, rt_key(rt), rt->rt_gateway, 2124 rt_mask(rt), rt->rt_flags, 0)); 2125#undef SIN6 2126} 2127 2128int 2129nd6_setdefaultiface(int ifindex) 2130{ 2131 int error = 0; 2132 2133 if (ifindex < 0 || V_if_index < ifindex) 2134 return (EINVAL); 2135 if (ifindex != 0 && !ifnet_byindex(ifindex)) 2136 return (EINVAL); 2137 2138 if (V_nd6_defifindex != ifindex) { 2139 V_nd6_defifindex = ifindex; 2140 if (V_nd6_defifindex > 0) 2141 V_nd6_defifp = ifnet_byindex(V_nd6_defifindex); 2142 else 2143 V_nd6_defifp = NULL; 2144 2145 /* 2146 * Our current implementation assumes one-to-one maping between 2147 * interfaces and links, so it would be natural to use the 2148 * default interface as the default link. 2149 */ 2150 scope6_setdefault(V_nd6_defifp); 2151 } 2152 2153 return (error); 2154} 2155