1 /* 2 * Linux INET6 implementation 3 * FIB front-end. 4 * 5 * Authors: 6 * Pedro Roque <roque@di.fc.ul.pt> 7 * 8 * This program is free software; you can redistribute it and/or 9 * modify it under the terms of the GNU General Public License 10 * as published by the Free Software Foundation; either version 11 * 2 of the License, or (at your option) any later version. 12 */ 13 14 /* Changes: 15 * 16 * YOSHIFUJI Hideaki @USAGI 17 * reworked default router selection. 18 * - respect outgoing interface 19 * - select from (probably) reachable routers (i.e. 20 * routers in REACHABLE, STALE, DELAY or PROBE states). 21 * - always select the same router if it is (probably) 22 * reachable. otherwise, round-robin the list. 23 * Ville Nuorvala 24 * Fixed routing subtrees. 25 */ 26 27 #define pr_fmt(fmt) "IPv6: " fmt 28 29 #include <linux/capability.h> 30 #include <linux/errno.h> 31 #include <linux/export.h> 32 #include <linux/types.h> 33 #include <linux/times.h> 34 #include <linux/socket.h> 35 #include <linux/sockios.h> 36 #include <linux/net.h> 37 #include <linux/route.h> 38 #include <linux/netdevice.h> 39 #include <linux/in6.h> 40 #include <linux/mroute6.h> 41 #include <linux/init.h> 42 #include <linux/if_arp.h> 43 #include <linux/proc_fs.h> 44 #include <linux/seq_file.h> 45 #include <linux/nsproxy.h> 46 #include <linux/slab.h> 47 #include <net/net_namespace.h> 48 #include <net/snmp.h> 49 #include <net/ipv6.h> 50 #include <net/ip6_fib.h> 51 #include <net/ip6_route.h> 52 #include <net/ndisc.h> 53 #include <net/addrconf.h> 54 #include <net/tcp.h> 55 #include <linux/rtnetlink.h> 56 #include <net/dst.h> 57 #include <net/xfrm.h> 58 #include <net/netevent.h> 59 #include <net/netlink.h> 60 #include <net/nexthop.h> 61 62 #include <asm/uaccess.h> 63 64 #ifdef CONFIG_SYSCTL 65 #include <linux/sysctl.h> 66 #endif 67 68 enum rt6_nud_state { 69 RT6_NUD_FAIL_HARD = -3, 70 RT6_NUD_FAIL_PROBE = -2, 71 RT6_NUD_FAIL_DO_RR = -1, 72 RT6_NUD_SUCCEED = 1 73 }; 74 75 static struct rt6_info *ip6_rt_copy(struct rt6_info *ort, 76 const struct in6_addr *dest); 77 static struct dst_entry *ip6_dst_check(struct dst_entry *dst, u32 cookie); 78 static unsigned int ip6_default_advmss(const struct dst_entry *dst); 79 static unsigned int ip6_mtu(const struct dst_entry *dst); 80 static struct dst_entry *ip6_negative_advice(struct dst_entry *); 81 static void ip6_dst_destroy(struct dst_entry *); 82 static void ip6_dst_ifdown(struct dst_entry *, 83 struct net_device *dev, int how); 84 static int ip6_dst_gc(struct dst_ops *ops); 85 86 static int ip6_pkt_discard(struct sk_buff *skb); 87 static int ip6_pkt_discard_out(struct sock *sk, struct sk_buff *skb); 88 static int ip6_pkt_prohibit(struct sk_buff *skb); 89 static int ip6_pkt_prohibit_out(struct sock *sk, struct sk_buff *skb); 90 static void ip6_link_failure(struct sk_buff *skb); 91 static void ip6_rt_update_pmtu(struct dst_entry *dst, struct sock *sk, 92 struct sk_buff *skb, u32 mtu); 93 static void rt6_do_redirect(struct dst_entry *dst, struct sock *sk, 94 struct sk_buff *skb); 95 static int rt6_score_route(struct rt6_info *rt, int oif, int strict); 96 97 #ifdef CONFIG_IPV6_ROUTE_INFO 98 static struct rt6_info *rt6_add_route_info(struct net *net, 99 const struct in6_addr *prefix, int prefixlen, 100 const struct in6_addr *gwaddr, int ifindex, 101 unsigned int pref); 102 static struct rt6_info *rt6_get_route_info(struct net *net, 103 const struct in6_addr *prefix, int prefixlen, 104 const struct in6_addr *gwaddr, int ifindex); 105 #endif 106 107 static void rt6_bind_peer(struct rt6_info *rt, int create) 108 { 109 struct inet_peer_base *base; 110 struct inet_peer *peer; 111 112 base = inetpeer_base_ptr(rt->_rt6i_peer); 113 if (!base) 114 return; 115 116 peer = inet_getpeer_v6(base, &rt->rt6i_dst.addr, create); 117 if (peer) { 118 if (!rt6_set_peer(rt, peer)) 119 inet_putpeer(peer); 120 } 121 } 122 123 static struct inet_peer *__rt6_get_peer(struct rt6_info *rt, int create) 124 { 125 if (rt6_has_peer(rt)) 126 return rt6_peer_ptr(rt); 127 128 rt6_bind_peer(rt, create); 129 return (rt6_has_peer(rt) ? rt6_peer_ptr(rt) : NULL); 130 } 131 132 static struct inet_peer *rt6_get_peer_create(struct rt6_info *rt) 133 { 134 return __rt6_get_peer(rt, 1); 135 } 136 137 static u32 *ipv6_cow_metrics(struct dst_entry *dst, unsigned long old) 138 { 139 struct rt6_info *rt = (struct rt6_info *) dst; 140 struct inet_peer *peer; 141 u32 *p = NULL; 142 143 if (!(rt->dst.flags & DST_HOST)) 144 return NULL; 145 146 peer = rt6_get_peer_create(rt); 147 if (peer) { 148 u32 *old_p = __DST_METRICS_PTR(old); 149 unsigned long prev, new; 150 151 p = peer->metrics; 152 if (inet_metrics_new(peer) || 153 (old & DST_METRICS_FORCE_OVERWRITE)) 154 memcpy(p, old_p, sizeof(u32) * RTAX_MAX); 155 156 new = (unsigned long) p; 157 prev = cmpxchg(&dst->_metrics, old, new); 158 159 if (prev != old) { 160 p = __DST_METRICS_PTR(prev); 161 if (prev & DST_METRICS_READ_ONLY) 162 p = NULL; 163 } 164 } 165 return p; 166 } 167 168 static inline const void *choose_neigh_daddr(struct rt6_info *rt, 169 struct sk_buff *skb, 170 const void *daddr) 171 { 172 struct in6_addr *p = &rt->rt6i_gateway; 173 174 if (!ipv6_addr_any(p)) 175 return (const void *) p; 176 else if (skb) 177 return &ipv6_hdr(skb)->daddr; 178 return daddr; 179 } 180 181 static struct neighbour *ip6_neigh_lookup(const struct dst_entry *dst, 182 struct sk_buff *skb, 183 const void *daddr) 184 { 185 struct rt6_info *rt = (struct rt6_info *) dst; 186 struct neighbour *n; 187 188 daddr = choose_neigh_daddr(rt, skb, daddr); 189 n = __ipv6_neigh_lookup(dst->dev, daddr); 190 if (n) 191 return n; 192 return neigh_create(&nd_tbl, daddr, dst->dev); 193 } 194 195 static struct dst_ops ip6_dst_ops_template = { 196 .family = AF_INET6, 197 .protocol = cpu_to_be16(ETH_P_IPV6), 198 .gc = ip6_dst_gc, 199 .gc_thresh = 1024, 200 .check = ip6_dst_check, 201 .default_advmss = ip6_default_advmss, 202 .mtu = ip6_mtu, 203 .cow_metrics = ipv6_cow_metrics, 204 .destroy = ip6_dst_destroy, 205 .ifdown = ip6_dst_ifdown, 206 .negative_advice = ip6_negative_advice, 207 .link_failure = ip6_link_failure, 208 .update_pmtu = ip6_rt_update_pmtu, 209 .redirect = rt6_do_redirect, 210 .local_out = __ip6_local_out, 211 .neigh_lookup = ip6_neigh_lookup, 212 }; 213 214 static unsigned int ip6_blackhole_mtu(const struct dst_entry *dst) 215 { 216 unsigned int mtu = dst_metric_raw(dst, RTAX_MTU); 217 218 return mtu ? : dst->dev->mtu; 219 } 220 221 static void ip6_rt_blackhole_update_pmtu(struct dst_entry *dst, struct sock *sk, 222 struct sk_buff *skb, u32 mtu) 223 { 224 } 225 226 static void ip6_rt_blackhole_redirect(struct dst_entry *dst, struct sock *sk, 227 struct sk_buff *skb) 228 { 229 } 230 231 static u32 *ip6_rt_blackhole_cow_metrics(struct dst_entry *dst, 232 unsigned long old) 233 { 234 return NULL; 235 } 236 237 static struct dst_ops ip6_dst_blackhole_ops = { 238 .family = AF_INET6, 239 .protocol = cpu_to_be16(ETH_P_IPV6), 240 .destroy = ip6_dst_destroy, 241 .check = ip6_dst_check, 242 .mtu = ip6_blackhole_mtu, 243 .default_advmss = ip6_default_advmss, 244 .update_pmtu = ip6_rt_blackhole_update_pmtu, 245 .redirect = ip6_rt_blackhole_redirect, 246 .cow_metrics = ip6_rt_blackhole_cow_metrics, 247 .neigh_lookup = ip6_neigh_lookup, 248 }; 249 250 static const u32 ip6_template_metrics[RTAX_MAX] = { 251 [RTAX_HOPLIMIT - 1] = 0, 252 }; 253 254 static const struct rt6_info ip6_null_entry_template = { 255 .dst = { 256 .__refcnt = ATOMIC_INIT(1), 257 .__use = 1, 258 .obsolete = DST_OBSOLETE_FORCE_CHK, 259 .error = -ENETUNREACH, 260 .input = ip6_pkt_discard, 261 .output = ip6_pkt_discard_out, 262 }, 263 .rt6i_flags = (RTF_REJECT | RTF_NONEXTHOP), 264 .rt6i_protocol = RTPROT_KERNEL, 265 .rt6i_metric = ~(u32) 0, 266 .rt6i_ref = ATOMIC_INIT(1), 267 }; 268 269 #ifdef CONFIG_IPV6_MULTIPLE_TABLES 270 271 static const struct rt6_info ip6_prohibit_entry_template = { 272 .dst = { 273 .__refcnt = ATOMIC_INIT(1), 274 .__use = 1, 275 .obsolete = DST_OBSOLETE_FORCE_CHK, 276 .error = -EACCES, 277 .input = ip6_pkt_prohibit, 278 .output = ip6_pkt_prohibit_out, 279 }, 280 .rt6i_flags = (RTF_REJECT | RTF_NONEXTHOP), 281 .rt6i_protocol = RTPROT_KERNEL, 282 .rt6i_metric = ~(u32) 0, 283 .rt6i_ref = ATOMIC_INIT(1), 284 }; 285 286 static const struct rt6_info ip6_blk_hole_entry_template = { 287 .dst = { 288 .__refcnt = ATOMIC_INIT(1), 289 .__use = 1, 290 .obsolete = DST_OBSOLETE_FORCE_CHK, 291 .error = -EINVAL, 292 .input = dst_discard, 293 .output = dst_discard_sk, 294 }, 295 .rt6i_flags = (RTF_REJECT | RTF_NONEXTHOP), 296 .rt6i_protocol = RTPROT_KERNEL, 297 .rt6i_metric = ~(u32) 0, 298 .rt6i_ref = ATOMIC_INIT(1), 299 }; 300 301 #endif 302 303 /* allocate dst with ip6_dst_ops */ 304 static inline struct rt6_info *ip6_dst_alloc(struct net *net, 305 struct net_device *dev, 306 int flags, 307 struct fib6_table *table) 308 { 309 struct rt6_info *rt = dst_alloc(&net->ipv6.ip6_dst_ops, dev, 310 0, DST_OBSOLETE_FORCE_CHK, flags); 311 312 if (rt) { 313 struct dst_entry *dst = &rt->dst; 314 315 memset(dst + 1, 0, sizeof(*rt) - sizeof(*dst)); 316 rt6_init_peer(rt, table ? &table->tb6_peers : net->ipv6.peers); 317 INIT_LIST_HEAD(&rt->rt6i_siblings); 318 } 319 return rt; 320 } 321 322 static void ip6_dst_destroy(struct dst_entry *dst) 323 { 324 struct rt6_info *rt = (struct rt6_info *)dst; 325 struct inet6_dev *idev = rt->rt6i_idev; 326 struct dst_entry *from = dst->from; 327 328 if (!(rt->dst.flags & DST_HOST)) 329 dst_destroy_metrics_generic(dst); 330 331 if (idev) { 332 rt->rt6i_idev = NULL; 333 in6_dev_put(idev); 334 } 335 336 dst->from = NULL; 337 dst_release(from); 338 339 if (rt6_has_peer(rt)) { 340 struct inet_peer *peer = rt6_peer_ptr(rt); 341 inet_putpeer(peer); 342 } 343 } 344 345 static void ip6_dst_ifdown(struct dst_entry *dst, struct net_device *dev, 346 int how) 347 { 348 struct rt6_info *rt = (struct rt6_info *)dst; 349 struct inet6_dev *idev = rt->rt6i_idev; 350 struct net_device *loopback_dev = 351 dev_net(dev)->loopback_dev; 352 353 if (dev != loopback_dev) { 354 if (idev && idev->dev == dev) { 355 struct inet6_dev *loopback_idev = 356 in6_dev_get(loopback_dev); 357 if (loopback_idev) { 358 rt->rt6i_idev = loopback_idev; 359 in6_dev_put(idev); 360 } 361 } 362 } 363 } 364 365 static bool rt6_check_expired(const struct rt6_info *rt) 366 { 367 if (rt->rt6i_flags & RTF_EXPIRES) { 368 if (time_after(jiffies, rt->dst.expires)) 369 return true; 370 } else if (rt->dst.from) { 371 return rt6_check_expired((struct rt6_info *) rt->dst.from); 372 } 373 return false; 374 } 375 376 /* Multipath route selection: 377 * Hash based function using packet header and flowlabel. 378 * Adapted from fib_info_hashfn() 379 */ 380 static int rt6_info_hash_nhsfn(unsigned int candidate_count, 381 const struct flowi6 *fl6) 382 { 383 unsigned int val = fl6->flowi6_proto; 384 385 val ^= ipv6_addr_hash(&fl6->daddr); 386 val ^= ipv6_addr_hash(&fl6->saddr); 387 388 /* Work only if this not encapsulated */ 389 switch (fl6->flowi6_proto) { 390 case IPPROTO_UDP: 391 case IPPROTO_TCP: 392 case IPPROTO_SCTP: 393 val ^= (__force u16)fl6->fl6_sport; 394 val ^= (__force u16)fl6->fl6_dport; 395 break; 396 397 case IPPROTO_ICMPV6: 398 val ^= (__force u16)fl6->fl6_icmp_type; 399 val ^= (__force u16)fl6->fl6_icmp_code; 400 break; 401 } 402 /* RFC6438 recommands to use flowlabel */ 403 val ^= (__force u32)fl6->flowlabel; 404 405 /* Perhaps, we need to tune, this function? */ 406 val = val ^ (val >> 7) ^ (val >> 12); 407 return val % candidate_count; 408 } 409 410 static struct rt6_info *rt6_multipath_select(struct rt6_info *match, 411 struct flowi6 *fl6, int oif, 412 int strict) 413 { 414 struct rt6_info *sibling, *next_sibling; 415 int route_choosen; 416 417 route_choosen = rt6_info_hash_nhsfn(match->rt6i_nsiblings + 1, fl6); 418 /* Don't change the route, if route_choosen == 0 419 * (siblings does not include ourself) 420 */ 421 if (route_choosen) 422 list_for_each_entry_safe(sibling, next_sibling, 423 &match->rt6i_siblings, rt6i_siblings) { 424 route_choosen--; 425 if (route_choosen == 0) { 426 if (rt6_score_route(sibling, oif, strict) < 0) 427 break; 428 match = sibling; 429 break; 430 } 431 } 432 return match; 433 } 434 435 /* 436 * Route lookup. Any table->tb6_lock is implied. 437 */ 438 439 static inline struct rt6_info *rt6_device_match(struct net *net, 440 struct rt6_info *rt, 441 const struct in6_addr *saddr, 442 int oif, 443 int flags) 444 { 445 struct rt6_info *local = NULL; 446 struct rt6_info *sprt; 447 448 if (!oif && ipv6_addr_any(saddr)) 449 goto out; 450 451 for (sprt = rt; sprt; sprt = sprt->dst.rt6_next) { 452 struct net_device *dev = sprt->dst.dev; 453 454 if (oif) { 455 if (dev->ifindex == oif) 456 return sprt; 457 if (dev->flags & IFF_LOOPBACK) { 458 if (!sprt->rt6i_idev || 459 sprt->rt6i_idev->dev->ifindex != oif) { 460 if (flags & RT6_LOOKUP_F_IFACE && oif) 461 continue; 462 if (local && (!oif || 463 local->rt6i_idev->dev->ifindex == oif)) 464 continue; 465 } 466 local = sprt; 467 } 468 } else { 469 if (ipv6_chk_addr(net, saddr, dev, 470 flags & RT6_LOOKUP_F_IFACE)) 471 return sprt; 472 } 473 } 474 475 if (oif) { 476 if (local) 477 return local; 478 479 if (flags & RT6_LOOKUP_F_IFACE) 480 return net->ipv6.ip6_null_entry; 481 } 482 out: 483 return rt; 484 } 485 486 #ifdef CONFIG_IPV6_ROUTER_PREF 487 struct __rt6_probe_work { 488 struct work_struct work; 489 struct in6_addr target; 490 struct net_device *dev; 491 }; 492 493 static void rt6_probe_deferred(struct work_struct *w) 494 { 495 struct in6_addr mcaddr; 496 struct __rt6_probe_work *work = 497 container_of(w, struct __rt6_probe_work, work); 498 499 addrconf_addr_solict_mult(&work->target, &mcaddr); 500 ndisc_send_ns(work->dev, NULL, &work->target, &mcaddr, NULL); 501 dev_put(work->dev); 502 kfree(w); 503 } 504 505 static void rt6_probe(struct rt6_info *rt) 506 { 507 struct neighbour *neigh; 508 /* 509 * Okay, this does not seem to be appropriate 510 * for now, however, we need to check if it 511 * is really so; aka Router Reachability Probing. 512 * 513 * Router Reachability Probe MUST be rate-limited 514 * to no more than one per minute. 515 */ 516 if (!rt || !(rt->rt6i_flags & RTF_GATEWAY)) 517 return; 518 rcu_read_lock_bh(); 519 neigh = __ipv6_neigh_lookup_noref(rt->dst.dev, &rt->rt6i_gateway); 520 if (neigh) { 521 write_lock(&neigh->lock); 522 if (neigh->nud_state & NUD_VALID) 523 goto out; 524 } 525 526 if (!neigh || 527 time_after(jiffies, neigh->updated + rt->rt6i_idev->cnf.rtr_probe_interval)) { 528 struct __rt6_probe_work *work; 529 530 work = kmalloc(sizeof(*work), GFP_ATOMIC); 531 532 if (neigh && work) 533 __neigh_set_probe_once(neigh); 534 535 if (neigh) 536 write_unlock(&neigh->lock); 537 538 if (work) { 539 INIT_WORK(&work->work, rt6_probe_deferred); 540 work->target = rt->rt6i_gateway; 541 dev_hold(rt->dst.dev); 542 work->dev = rt->dst.dev; 543 schedule_work(&work->work); 544 } 545 } else { 546 out: 547 write_unlock(&neigh->lock); 548 } 549 rcu_read_unlock_bh(); 550 } 551 #else 552 static inline void rt6_probe(struct rt6_info *rt) 553 { 554 } 555 #endif 556 557 /* 558 * Default Router Selection (RFC 2461 6.3.6) 559 */ 560 static inline int rt6_check_dev(struct rt6_info *rt, int oif) 561 { 562 struct net_device *dev = rt->dst.dev; 563 if (!oif || dev->ifindex == oif) 564 return 2; 565 if ((dev->flags & IFF_LOOPBACK) && 566 rt->rt6i_idev && rt->rt6i_idev->dev->ifindex == oif) 567 return 1; 568 return 0; 569 } 570 571 static inline enum rt6_nud_state rt6_check_neigh(struct rt6_info *rt) 572 { 573 struct neighbour *neigh; 574 enum rt6_nud_state ret = RT6_NUD_FAIL_HARD; 575 576 if (rt->rt6i_flags & RTF_NONEXTHOP || 577 !(rt->rt6i_flags & RTF_GATEWAY)) 578 return RT6_NUD_SUCCEED; 579 580 rcu_read_lock_bh(); 581 neigh = __ipv6_neigh_lookup_noref(rt->dst.dev, &rt->rt6i_gateway); 582 if (neigh) { 583 read_lock(&neigh->lock); 584 if (neigh->nud_state & NUD_VALID) 585 ret = RT6_NUD_SUCCEED; 586 #ifdef CONFIG_IPV6_ROUTER_PREF 587 else if (!(neigh->nud_state & NUD_FAILED)) 588 ret = RT6_NUD_SUCCEED; 589 else 590 ret = RT6_NUD_FAIL_PROBE; 591 #endif 592 read_unlock(&neigh->lock); 593 } else { 594 ret = IS_ENABLED(CONFIG_IPV6_ROUTER_PREF) ? 595 RT6_NUD_SUCCEED : RT6_NUD_FAIL_DO_RR; 596 } 597 rcu_read_unlock_bh(); 598 599 return ret; 600 } 601 602 static int rt6_score_route(struct rt6_info *rt, int oif, 603 int strict) 604 { 605 int m; 606 607 m = rt6_check_dev(rt, oif); 608 if (!m && (strict & RT6_LOOKUP_F_IFACE)) 609 return RT6_NUD_FAIL_HARD; 610 #ifdef CONFIG_IPV6_ROUTER_PREF 611 m |= IPV6_DECODE_PREF(IPV6_EXTRACT_PREF(rt->rt6i_flags)) << 2; 612 #endif 613 if (strict & RT6_LOOKUP_F_REACHABLE) { 614 int n = rt6_check_neigh(rt); 615 if (n < 0) 616 return n; 617 } 618 return m; 619 } 620 621 static struct rt6_info *find_match(struct rt6_info *rt, int oif, int strict, 622 int *mpri, struct rt6_info *match, 623 bool *do_rr) 624 { 625 int m; 626 bool match_do_rr = false; 627 628 if (rt6_check_expired(rt)) 629 goto out; 630 631 m = rt6_score_route(rt, oif, strict); 632 if (m == RT6_NUD_FAIL_DO_RR) { 633 match_do_rr = true; 634 m = 0; /* lowest valid score */ 635 } else if (m == RT6_NUD_FAIL_HARD) { 636 goto out; 637 } 638 639 if (strict & RT6_LOOKUP_F_REACHABLE) 640 rt6_probe(rt); 641 642 /* note that m can be RT6_NUD_FAIL_PROBE at this point */ 643 if (m > *mpri) { 644 *do_rr = match_do_rr; 645 *mpri = m; 646 match = rt; 647 } 648 out: 649 return match; 650 } 651 652 static struct rt6_info *find_rr_leaf(struct fib6_node *fn, 653 struct rt6_info *rr_head, 654 u32 metric, int oif, int strict, 655 bool *do_rr) 656 { 657 struct rt6_info *rt, *match; 658 int mpri = -1; 659 660 match = NULL; 661 for (rt = rr_head; rt && rt->rt6i_metric == metric; 662 rt = rt->dst.rt6_next) 663 match = find_match(rt, oif, strict, &mpri, match, do_rr); 664 for (rt = fn->leaf; rt && rt != rr_head && rt->rt6i_metric == metric; 665 rt = rt->dst.rt6_next) 666 match = find_match(rt, oif, strict, &mpri, match, do_rr); 667 668 return match; 669 } 670 671 static struct rt6_info *rt6_select(struct fib6_node *fn, int oif, int strict) 672 { 673 struct rt6_info *match, *rt0; 674 struct net *net; 675 bool do_rr = false; 676 677 rt0 = fn->rr_ptr; 678 if (!rt0) 679 fn->rr_ptr = rt0 = fn->leaf; 680 681 match = find_rr_leaf(fn, rt0, rt0->rt6i_metric, oif, strict, 682 &do_rr); 683 684 if (do_rr) { 685 struct rt6_info *next = rt0->dst.rt6_next; 686 687 /* no entries matched; do round-robin */ 688 if (!next || next->rt6i_metric != rt0->rt6i_metric) 689 next = fn->leaf; 690 691 if (next != rt0) 692 fn->rr_ptr = next; 693 } 694 695 net = dev_net(rt0->dst.dev); 696 return match ? match : net->ipv6.ip6_null_entry; 697 } 698 699 #ifdef CONFIG_IPV6_ROUTE_INFO 700 int rt6_route_rcv(struct net_device *dev, u8 *opt, int len, 701 const struct in6_addr *gwaddr) 702 { 703 struct net *net = dev_net(dev); 704 struct route_info *rinfo = (struct route_info *) opt; 705 struct in6_addr prefix_buf, *prefix; 706 unsigned int pref; 707 unsigned long lifetime; 708 struct rt6_info *rt; 709 710 if (len < sizeof(struct route_info)) { 711 return -EINVAL; 712 } 713 714 /* Sanity check for prefix_len and length */ 715 if (rinfo->length > 3) { 716 return -EINVAL; 717 } else if (rinfo->prefix_len > 128) { 718 return -EINVAL; 719 } else if (rinfo->prefix_len > 64) { 720 if (rinfo->length < 2) { 721 return -EINVAL; 722 } 723 } else if (rinfo->prefix_len > 0) { 724 if (rinfo->length < 1) { 725 return -EINVAL; 726 } 727 } 728 729 pref = rinfo->route_pref; 730 if (pref == ICMPV6_ROUTER_PREF_INVALID) 731 return -EINVAL; 732 733 lifetime = addrconf_timeout_fixup(ntohl(rinfo->lifetime), HZ); 734 735 if (rinfo->length == 3) 736 prefix = (struct in6_addr *)rinfo->prefix; 737 else { 738 /* this function is safe */ 739 ipv6_addr_prefix(&prefix_buf, 740 (struct in6_addr *)rinfo->prefix, 741 rinfo->prefix_len); 742 prefix = &prefix_buf; 743 } 744 745 if (rinfo->prefix_len == 0) 746 rt = rt6_get_dflt_router(gwaddr, dev); 747 else 748 rt = rt6_get_route_info(net, prefix, rinfo->prefix_len, 749 gwaddr, dev->ifindex); 750 751 if (rt && !lifetime) { 752 ip6_del_rt(rt); 753 rt = NULL; 754 } 755 756 if (!rt && lifetime) 757 rt = rt6_add_route_info(net, prefix, rinfo->prefix_len, gwaddr, dev->ifindex, 758 pref); 759 else if (rt) 760 rt->rt6i_flags = RTF_ROUTEINFO | 761 (rt->rt6i_flags & ~RTF_PREF_MASK) | RTF_PREF(pref); 762 763 if (rt) { 764 if (!addrconf_finite_timeout(lifetime)) 765 rt6_clean_expires(rt); 766 else 767 rt6_set_expires(rt, jiffies + HZ * lifetime); 768 769 ip6_rt_put(rt); 770 } 771 return 0; 772 } 773 #endif 774 775 static struct fib6_node* fib6_backtrack(struct fib6_node *fn, 776 struct in6_addr *saddr) 777 { 778 struct fib6_node *pn; 779 while (1) { 780 if (fn->fn_flags & RTN_TL_ROOT) 781 return NULL; 782 pn = fn->parent; 783 if (FIB6_SUBTREE(pn) && FIB6_SUBTREE(pn) != fn) 784 fn = fib6_lookup(FIB6_SUBTREE(pn), NULL, saddr); 785 else 786 fn = pn; 787 if (fn->fn_flags & RTN_RTINFO) 788 return fn; 789 } 790 } 791 792 static struct rt6_info *ip6_pol_route_lookup(struct net *net, 793 struct fib6_table *table, 794 struct flowi6 *fl6, int flags) 795 { 796 struct fib6_node *fn; 797 struct rt6_info *rt; 798 799 read_lock_bh(&table->tb6_lock); 800 fn = fib6_lookup(&table->tb6_root, &fl6->daddr, &fl6->saddr); 801 restart: 802 rt = fn->leaf; 803 rt = rt6_device_match(net, rt, &fl6->saddr, fl6->flowi6_oif, flags); 804 if (rt->rt6i_nsiblings && fl6->flowi6_oif == 0) 805 rt = rt6_multipath_select(rt, fl6, fl6->flowi6_oif, flags); 806 if (rt == net->ipv6.ip6_null_entry) { 807 fn = fib6_backtrack(fn, &fl6->saddr); 808 if (fn) 809 goto restart; 810 } 811 dst_use(&rt->dst, jiffies); 812 read_unlock_bh(&table->tb6_lock); 813 return rt; 814 815 } 816 817 struct dst_entry *ip6_route_lookup(struct net *net, struct flowi6 *fl6, 818 int flags) 819 { 820 return fib6_rule_lookup(net, fl6, flags, ip6_pol_route_lookup); 821 } 822 EXPORT_SYMBOL_GPL(ip6_route_lookup); 823 824 struct rt6_info *rt6_lookup(struct net *net, const struct in6_addr *daddr, 825 const struct in6_addr *saddr, int oif, int strict) 826 { 827 struct flowi6 fl6 = { 828 .flowi6_oif = oif, 829 .daddr = *daddr, 830 }; 831 struct dst_entry *dst; 832 int flags = strict ? RT6_LOOKUP_F_IFACE : 0; 833 834 if (saddr) { 835 memcpy(&fl6.saddr, saddr, sizeof(*saddr)); 836 flags |= RT6_LOOKUP_F_HAS_SADDR; 837 } 838 839 dst = fib6_rule_lookup(net, &fl6, flags, ip6_pol_route_lookup); 840 if (dst->error == 0) 841 return (struct rt6_info *) dst; 842 843 dst_release(dst); 844 845 return NULL; 846 } 847 EXPORT_SYMBOL(rt6_lookup); 848 849 /* ip6_ins_rt is called with FREE table->tb6_lock. 850 It takes new route entry, the addition fails by any reason the 851 route is freed. In any case, if caller does not hold it, it may 852 be destroyed. 853 */ 854 855 static int __ip6_ins_rt(struct rt6_info *rt, struct nl_info *info, 856 struct nlattr *mx, int mx_len) 857 { 858 int err; 859 struct fib6_table *table; 860 861 table = rt->rt6i_table; 862 write_lock_bh(&table->tb6_lock); 863 err = fib6_add(&table->tb6_root, rt, info, mx, mx_len); 864 write_unlock_bh(&table->tb6_lock); 865 866 return err; 867 } 868 869 int ip6_ins_rt(struct rt6_info *rt) 870 { 871 struct nl_info info = { 872 .nl_net = dev_net(rt->dst.dev), 873 }; 874 return __ip6_ins_rt(rt, &info, NULL, 0); 875 } 876 877 static struct rt6_info *rt6_alloc_cow(struct rt6_info *ort, 878 const struct in6_addr *daddr, 879 const struct in6_addr *saddr) 880 { 881 struct rt6_info *rt; 882 883 /* 884 * Clone the route. 885 */ 886 887 rt = ip6_rt_copy(ort, daddr); 888 889 if (rt) { 890 if (ort->rt6i_dst.plen != 128 && 891 ipv6_addr_equal(&ort->rt6i_dst.addr, daddr)) 892 rt->rt6i_flags |= RTF_ANYCAST; 893 894 rt->rt6i_flags |= RTF_CACHE; 895 896 #ifdef CONFIG_IPV6_SUBTREES 897 if (rt->rt6i_src.plen && saddr) { 898 rt->rt6i_src.addr = *saddr; 899 rt->rt6i_src.plen = 128; 900 } 901 #endif 902 } 903 904 return rt; 905 } 906 907 static struct rt6_info *rt6_alloc_clone(struct rt6_info *ort, 908 const struct in6_addr *daddr) 909 { 910 struct rt6_info *rt = ip6_rt_copy(ort, daddr); 911 912 if (rt) 913 rt->rt6i_flags |= RTF_CACHE; 914 return rt; 915 } 916 917 static struct rt6_info *ip6_pol_route(struct net *net, struct fib6_table *table, int oif, 918 struct flowi6 *fl6, int flags) 919 { 920 struct fib6_node *fn, *saved_fn; 921 struct rt6_info *rt, *nrt; 922 int strict = 0; 923 int attempts = 3; 924 int err; 925 926 strict |= flags & RT6_LOOKUP_F_IFACE; 927 if (net->ipv6.devconf_all->forwarding == 0) 928 strict |= RT6_LOOKUP_F_REACHABLE; 929 930 redo_fib6_lookup_lock: 931 read_lock_bh(&table->tb6_lock); 932 933 fn = fib6_lookup(&table->tb6_root, &fl6->daddr, &fl6->saddr); 934 saved_fn = fn; 935 936 redo_rt6_select: 937 rt = rt6_select(fn, oif, strict); 938 if (rt->rt6i_nsiblings) 939 rt = rt6_multipath_select(rt, fl6, oif, strict); 940 if (rt == net->ipv6.ip6_null_entry) { 941 fn = fib6_backtrack(fn, &fl6->saddr); 942 if (fn) 943 goto redo_rt6_select; 944 else if (strict & RT6_LOOKUP_F_REACHABLE) { 945 /* also consider unreachable route */ 946 strict &= ~RT6_LOOKUP_F_REACHABLE; 947 fn = saved_fn; 948 goto redo_rt6_select; 949 } else { 950 dst_hold(&rt->dst); 951 read_unlock_bh(&table->tb6_lock); 952 goto out2; 953 } 954 } 955 956 dst_hold(&rt->dst); 957 read_unlock_bh(&table->tb6_lock); 958 959 if (rt->rt6i_flags & RTF_CACHE) 960 goto out2; 961 962 if (!(rt->rt6i_flags & (RTF_NONEXTHOP | RTF_GATEWAY))) 963 nrt = rt6_alloc_cow(rt, &fl6->daddr, &fl6->saddr); 964 else if (!(rt->dst.flags & DST_HOST)) 965 nrt = rt6_alloc_clone(rt, &fl6->daddr); 966 else 967 goto out2; 968 969 ip6_rt_put(rt); 970 rt = nrt ? : net->ipv6.ip6_null_entry; 971 972 dst_hold(&rt->dst); 973 if (nrt) { 974 err = ip6_ins_rt(nrt); 975 if (!err) 976 goto out2; 977 } 978 979 if (--attempts <= 0) 980 goto out2; 981 982 /* 983 * Race condition! In the gap, when table->tb6_lock was 984 * released someone could insert this route. Relookup. 985 */ 986 ip6_rt_put(rt); 987 goto redo_fib6_lookup_lock; 988 989 out2: 990 rt->dst.lastuse = jiffies; 991 rt->dst.__use++; 992 993 return rt; 994 } 995 996 static struct rt6_info *ip6_pol_route_input(struct net *net, struct fib6_table *table, 997 struct flowi6 *fl6, int flags) 998 { 999 return ip6_pol_route(net, table, fl6->flowi6_iif, fl6, flags); 1000 } 1001 1002 static struct dst_entry *ip6_route_input_lookup(struct net *net, 1003 struct net_device *dev, 1004 struct flowi6 *fl6, int flags) 1005 { 1006 if (rt6_need_strict(&fl6->daddr) && dev->type != ARPHRD_PIMREG) 1007 flags |= RT6_LOOKUP_F_IFACE; 1008 1009 return fib6_rule_lookup(net, fl6, flags, ip6_pol_route_input); 1010 } 1011 1012 void ip6_route_input(struct sk_buff *skb) 1013 { 1014 const struct ipv6hdr *iph = ipv6_hdr(skb); 1015 struct net *net = dev_net(skb->dev); 1016 int flags = RT6_LOOKUP_F_HAS_SADDR; 1017 struct flowi6 fl6 = { 1018 .flowi6_iif = skb->dev->ifindex, 1019 .daddr = iph->daddr, 1020 .saddr = iph->saddr, 1021 .flowlabel = ip6_flowinfo(iph), 1022 .flowi6_mark = skb->mark, 1023 .flowi6_proto = iph->nexthdr, 1024 }; 1025 1026 skb_dst_set(skb, ip6_route_input_lookup(net, skb->dev, &fl6, flags)); 1027 } 1028 1029 static struct rt6_info *ip6_pol_route_output(struct net *net, struct fib6_table *table, 1030 struct flowi6 *fl6, int flags) 1031 { 1032 return ip6_pol_route(net, table, fl6->flowi6_oif, fl6, flags); 1033 } 1034 1035 struct dst_entry *ip6_route_output(struct net *net, const struct sock *sk, 1036 struct flowi6 *fl6) 1037 { 1038 int flags = 0; 1039 1040 fl6->flowi6_iif = LOOPBACK_IFINDEX; 1041 1042 if ((sk && sk->sk_bound_dev_if) || rt6_need_strict(&fl6->daddr)) 1043 flags |= RT6_LOOKUP_F_IFACE; 1044 1045 if (!ipv6_addr_any(&fl6->saddr)) 1046 flags |= RT6_LOOKUP_F_HAS_SADDR; 1047 else if (sk) 1048 flags |= rt6_srcprefs2flags(inet6_sk(sk)->srcprefs); 1049 1050 return fib6_rule_lookup(net, fl6, flags, ip6_pol_route_output); 1051 } 1052 EXPORT_SYMBOL(ip6_route_output); 1053 1054 struct dst_entry *ip6_blackhole_route(struct net *net, struct dst_entry *dst_orig) 1055 { 1056 struct rt6_info *rt, *ort = (struct rt6_info *) dst_orig; 1057 struct dst_entry *new = NULL; 1058 1059 rt = dst_alloc(&ip6_dst_blackhole_ops, ort->dst.dev, 1, DST_OBSOLETE_NONE, 0); 1060 if (rt) { 1061 new = &rt->dst; 1062 1063 memset(new + 1, 0, sizeof(*rt) - sizeof(*new)); 1064 rt6_init_peer(rt, net->ipv6.peers); 1065 1066 new->__use = 1; 1067 new->input = dst_discard; 1068 new->output = dst_discard_sk; 1069 1070 if (dst_metrics_read_only(&ort->dst)) 1071 new->_metrics = ort->dst._metrics; 1072 else 1073 dst_copy_metrics(new, &ort->dst); 1074 rt->rt6i_idev = ort->rt6i_idev; 1075 if (rt->rt6i_idev) 1076 in6_dev_hold(rt->rt6i_idev); 1077 1078 rt->rt6i_gateway = ort->rt6i_gateway; 1079 rt->rt6i_flags = ort->rt6i_flags; 1080 rt->rt6i_metric = 0; 1081 1082 memcpy(&rt->rt6i_dst, &ort->rt6i_dst, sizeof(struct rt6key)); 1083 #ifdef CONFIG_IPV6_SUBTREES 1084 memcpy(&rt->rt6i_src, &ort->rt6i_src, sizeof(struct rt6key)); 1085 #endif 1086 1087 dst_free(new); 1088 } 1089 1090 dst_release(dst_orig); 1091 return new ? new : ERR_PTR(-ENOMEM); 1092 } 1093 1094 /* 1095 * Destination cache support functions 1096 */ 1097 1098 static struct dst_entry *ip6_dst_check(struct dst_entry *dst, u32 cookie) 1099 { 1100 struct rt6_info *rt; 1101 1102 rt = (struct rt6_info *) dst; 1103 1104 /* All IPV6 dsts are created with ->obsolete set to the value 1105 * DST_OBSOLETE_FORCE_CHK which forces validation calls down 1106 * into this function always. 1107 */ 1108 if (!rt->rt6i_node || (rt->rt6i_node->fn_sernum != cookie)) 1109 return NULL; 1110 1111 if (rt6_check_expired(rt)) 1112 return NULL; 1113 1114 return dst; 1115 } 1116 1117 static struct dst_entry *ip6_negative_advice(struct dst_entry *dst) 1118 { 1119 struct rt6_info *rt = (struct rt6_info *) dst; 1120 1121 if (rt) { 1122 if (rt->rt6i_flags & RTF_CACHE) { 1123 if (rt6_check_expired(rt)) { 1124 ip6_del_rt(rt); 1125 dst = NULL; 1126 } 1127 } else { 1128 dst_release(dst); 1129 dst = NULL; 1130 } 1131 } 1132 return dst; 1133 } 1134 1135 static void ip6_link_failure(struct sk_buff *skb) 1136 { 1137 struct rt6_info *rt; 1138 1139 icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_ADDR_UNREACH, 0); 1140 1141 rt = (struct rt6_info *) skb_dst(skb); 1142 if (rt) { 1143 if (rt->rt6i_flags & RTF_CACHE) { 1144 dst_hold(&rt->dst); 1145 if (ip6_del_rt(rt)) 1146 dst_free(&rt->dst); 1147 } else if (rt->rt6i_node && (rt->rt6i_flags & RTF_DEFAULT)) { 1148 rt->rt6i_node->fn_sernum = -1; 1149 } 1150 } 1151 } 1152 1153 static void ip6_rt_update_pmtu(struct dst_entry *dst, struct sock *sk, 1154 struct sk_buff *skb, u32 mtu) 1155 { 1156 struct rt6_info *rt6 = (struct rt6_info *)dst; 1157 1158 dst_confirm(dst); 1159 if (mtu < dst_mtu(dst) && rt6->rt6i_dst.plen == 128) { 1160 struct net *net = dev_net(dst->dev); 1161 1162 rt6->rt6i_flags |= RTF_MODIFIED; 1163 if (mtu < IPV6_MIN_MTU) 1164 mtu = IPV6_MIN_MTU; 1165 1166 dst_metric_set(dst, RTAX_MTU, mtu); 1167 rt6_update_expires(rt6, net->ipv6.sysctl.ip6_rt_mtu_expires); 1168 } 1169 } 1170 1171 void ip6_update_pmtu(struct sk_buff *skb, struct net *net, __be32 mtu, 1172 int oif, u32 mark) 1173 { 1174 const struct ipv6hdr *iph = (struct ipv6hdr *) skb->data; 1175 struct dst_entry *dst; 1176 struct flowi6 fl6; 1177 1178 memset(&fl6, 0, sizeof(fl6)); 1179 fl6.flowi6_oif = oif; 1180 fl6.flowi6_mark = mark ? mark : IP6_REPLY_MARK(net, skb->mark); 1181 fl6.daddr = iph->daddr; 1182 fl6.saddr = iph->saddr; 1183 fl6.flowlabel = ip6_flowinfo(iph); 1184 1185 dst = ip6_route_output(net, NULL, &fl6); 1186 if (!dst->error) 1187 ip6_rt_update_pmtu(dst, NULL, skb, ntohl(mtu)); 1188 dst_release(dst); 1189 } 1190 EXPORT_SYMBOL_GPL(ip6_update_pmtu); 1191 1192 void ip6_sk_update_pmtu(struct sk_buff *skb, struct sock *sk, __be32 mtu) 1193 { 1194 ip6_update_pmtu(skb, sock_net(sk), mtu, 1195 sk->sk_bound_dev_if, sk->sk_mark); 1196 } 1197 EXPORT_SYMBOL_GPL(ip6_sk_update_pmtu); 1198 1199 /* Handle redirects */ 1200 struct ip6rd_flowi { 1201 struct flowi6 fl6; 1202 struct in6_addr gateway; 1203 }; 1204 1205 static struct rt6_info *__ip6_route_redirect(struct net *net, 1206 struct fib6_table *table, 1207 struct flowi6 *fl6, 1208 int flags) 1209 { 1210 struct ip6rd_flowi *rdfl = (struct ip6rd_flowi *)fl6; 1211 struct rt6_info *rt; 1212 struct fib6_node *fn; 1213 1214 /* Get the "current" route for this destination and 1215 * check if the redirect has come from approriate router. 1216 * 1217 * RFC 4861 specifies that redirects should only be 1218 * accepted if they come from the nexthop to the target. 1219 * Due to the way the routes are chosen, this notion 1220 * is a bit fuzzy and one might need to check all possible 1221 * routes. 1222 */ 1223 1224 read_lock_bh(&table->tb6_lock); 1225 fn = fib6_lookup(&table->tb6_root, &fl6->daddr, &fl6->saddr); 1226 restart: 1227 for (rt = fn->leaf; rt; rt = rt->dst.rt6_next) { 1228 if (rt6_check_expired(rt)) 1229 continue; 1230 if (rt->dst.error) 1231 break; 1232 if (!(rt->rt6i_flags & RTF_GATEWAY)) 1233 continue; 1234 if (fl6->flowi6_oif != rt->dst.dev->ifindex) 1235 continue; 1236 if (!ipv6_addr_equal(&rdfl->gateway, &rt->rt6i_gateway)) 1237 continue; 1238 break; 1239 } 1240 1241 if (!rt) 1242 rt = net->ipv6.ip6_null_entry; 1243 else if (rt->dst.error) { 1244 rt = net->ipv6.ip6_null_entry; 1245 goto out; 1246 } 1247 1248 if (rt == net->ipv6.ip6_null_entry) { 1249 fn = fib6_backtrack(fn, &fl6->saddr); 1250 if (fn) 1251 goto restart; 1252 } 1253 1254 out: 1255 dst_hold(&rt->dst); 1256 1257 read_unlock_bh(&table->tb6_lock); 1258 1259 return rt; 1260 }; 1261 1262 static struct dst_entry *ip6_route_redirect(struct net *net, 1263 const struct flowi6 *fl6, 1264 const struct in6_addr *gateway) 1265 { 1266 int flags = RT6_LOOKUP_F_HAS_SADDR; 1267 struct ip6rd_flowi rdfl; 1268 1269 rdfl.fl6 = *fl6; 1270 rdfl.gateway = *gateway; 1271 1272 return fib6_rule_lookup(net, &rdfl.fl6, 1273 flags, __ip6_route_redirect); 1274 } 1275 1276 void ip6_redirect(struct sk_buff *skb, struct net *net, int oif, u32 mark) 1277 { 1278 const struct ipv6hdr *iph = (struct ipv6hdr *) skb->data; 1279 struct dst_entry *dst; 1280 struct flowi6 fl6; 1281 1282 memset(&fl6, 0, sizeof(fl6)); 1283 fl6.flowi6_iif = LOOPBACK_IFINDEX; 1284 fl6.flowi6_oif = oif; 1285 fl6.flowi6_mark = mark; 1286 fl6.daddr = iph->daddr; 1287 fl6.saddr = iph->saddr; 1288 fl6.flowlabel = ip6_flowinfo(iph); 1289 1290 dst = ip6_route_redirect(net, &fl6, &ipv6_hdr(skb)->saddr); 1291 rt6_do_redirect(dst, NULL, skb); 1292 dst_release(dst); 1293 } 1294 EXPORT_SYMBOL_GPL(ip6_redirect); 1295 1296 void ip6_redirect_no_header(struct sk_buff *skb, struct net *net, int oif, 1297 u32 mark) 1298 { 1299 const struct ipv6hdr *iph = ipv6_hdr(skb); 1300 const struct rd_msg *msg = (struct rd_msg *)icmp6_hdr(skb); 1301 struct dst_entry *dst; 1302 struct flowi6 fl6; 1303 1304 memset(&fl6, 0, sizeof(fl6)); 1305 fl6.flowi6_iif = LOOPBACK_IFINDEX; 1306 fl6.flowi6_oif = oif; 1307 fl6.flowi6_mark = mark; 1308 fl6.daddr = msg->dest; 1309 fl6.saddr = iph->daddr; 1310 1311 dst = ip6_route_redirect(net, &fl6, &iph->saddr); 1312 rt6_do_redirect(dst, NULL, skb); 1313 dst_release(dst); 1314 } 1315 1316 void ip6_sk_redirect(struct sk_buff *skb, struct sock *sk) 1317 { 1318 ip6_redirect(skb, sock_net(sk), sk->sk_bound_dev_if, sk->sk_mark); 1319 } 1320 EXPORT_SYMBOL_GPL(ip6_sk_redirect); 1321 1322 static unsigned int ip6_default_advmss(const struct dst_entry *dst) 1323 { 1324 struct net_device *dev = dst->dev; 1325 unsigned int mtu = dst_mtu(dst); 1326 struct net *net = dev_net(dev); 1327 1328 mtu -= sizeof(struct ipv6hdr) + sizeof(struct tcphdr); 1329 1330 if (mtu < net->ipv6.sysctl.ip6_rt_min_advmss) 1331 mtu = net->ipv6.sysctl.ip6_rt_min_advmss; 1332 1333 /* 1334 * Maximal non-jumbo IPv6 payload is IPV6_MAXPLEN and 1335 * corresponding MSS is IPV6_MAXPLEN - tcp_header_size. 1336 * IPV6_MAXPLEN is also valid and means: "any MSS, 1337 * rely only on pmtu discovery" 1338 */ 1339 if (mtu > IPV6_MAXPLEN - sizeof(struct tcphdr)) 1340 mtu = IPV6_MAXPLEN; 1341 return mtu; 1342 } 1343 1344 static unsigned int ip6_mtu(const struct dst_entry *dst) 1345 { 1346 struct inet6_dev *idev; 1347 unsigned int mtu = dst_metric_raw(dst, RTAX_MTU); 1348 1349 if (mtu) 1350 goto out; 1351 1352 mtu = IPV6_MIN_MTU; 1353 1354 rcu_read_lock(); 1355 idev = __in6_dev_get(dst->dev); 1356 if (idev) 1357 mtu = idev->cnf.mtu6; 1358 rcu_read_unlock(); 1359 1360 out: 1361 return min_t(unsigned int, mtu, IP6_MAX_MTU); 1362 } 1363 1364 static struct dst_entry *icmp6_dst_gc_list; 1365 static DEFINE_SPINLOCK(icmp6_dst_lock); 1366 1367 struct dst_entry *icmp6_dst_alloc(struct net_device *dev, 1368 struct flowi6 *fl6) 1369 { 1370 struct dst_entry *dst; 1371 struct rt6_info *rt; 1372 struct inet6_dev *idev = in6_dev_get(dev); 1373 struct net *net = dev_net(dev); 1374 1375 if (unlikely(!idev)) 1376 return ERR_PTR(-ENODEV); 1377 1378 rt = ip6_dst_alloc(net, dev, 0, NULL); 1379 if (unlikely(!rt)) { 1380 in6_dev_put(idev); 1381 dst = ERR_PTR(-ENOMEM); 1382 goto out; 1383 } 1384 1385 rt->dst.flags |= DST_HOST; 1386 rt->dst.output = ip6_output; 1387 atomic_set(&rt->dst.__refcnt, 1); 1388 rt->rt6i_gateway = fl6->daddr; 1389 rt->rt6i_dst.addr = fl6->daddr; 1390 rt->rt6i_dst.plen = 128; 1391 rt->rt6i_idev = idev; 1392 dst_metric_set(&rt->dst, RTAX_HOPLIMIT, 0); 1393 1394 spin_lock_bh(&icmp6_dst_lock); 1395 rt->dst.next = icmp6_dst_gc_list; 1396 icmp6_dst_gc_list = &rt->dst; 1397 spin_unlock_bh(&icmp6_dst_lock); 1398 1399 fib6_force_start_gc(net); 1400 1401 dst = xfrm_lookup(net, &rt->dst, flowi6_to_flowi(fl6), NULL, 0); 1402 1403 out: 1404 return dst; 1405 } 1406 1407 int icmp6_dst_gc(void) 1408 { 1409 struct dst_entry *dst, **pprev; 1410 int more = 0; 1411 1412 spin_lock_bh(&icmp6_dst_lock); 1413 pprev = &icmp6_dst_gc_list; 1414 1415 while ((dst = *pprev) != NULL) { 1416 if (!atomic_read(&dst->__refcnt)) { 1417 *pprev = dst->next; 1418 dst_free(dst); 1419 } else { 1420 pprev = &dst->next; 1421 ++more; 1422 } 1423 } 1424 1425 spin_unlock_bh(&icmp6_dst_lock); 1426 1427 return more; 1428 } 1429 1430 static void icmp6_clean_all(int (*func)(struct rt6_info *rt, void *arg), 1431 void *arg) 1432 { 1433 struct dst_entry *dst, **pprev; 1434 1435 spin_lock_bh(&icmp6_dst_lock); 1436 pprev = &icmp6_dst_gc_list; 1437 while ((dst = *pprev) != NULL) { 1438 struct rt6_info *rt = (struct rt6_info *) dst; 1439 if (func(rt, arg)) { 1440 *pprev = dst->next; 1441 dst_free(dst); 1442 } else { 1443 pprev = &dst->next; 1444 } 1445 } 1446 spin_unlock_bh(&icmp6_dst_lock); 1447 } 1448 1449 static int ip6_dst_gc(struct dst_ops *ops) 1450 { 1451 struct net *net = container_of(ops, struct net, ipv6.ip6_dst_ops); 1452 int rt_min_interval = net->ipv6.sysctl.ip6_rt_gc_min_interval; 1453 int rt_max_size = net->ipv6.sysctl.ip6_rt_max_size; 1454 int rt_elasticity = net->ipv6.sysctl.ip6_rt_gc_elasticity; 1455 int rt_gc_timeout = net->ipv6.sysctl.ip6_rt_gc_timeout; 1456 unsigned long rt_last_gc = net->ipv6.ip6_rt_last_gc; 1457 int entries; 1458 1459 entries = dst_entries_get_fast(ops); 1460 if (time_after(rt_last_gc + rt_min_interval, jiffies) && 1461 entries <= rt_max_size) 1462 goto out; 1463 1464 net->ipv6.ip6_rt_gc_expire++; 1465 fib6_run_gc(net->ipv6.ip6_rt_gc_expire, net, true); 1466 entries = dst_entries_get_slow(ops); 1467 if (entries < ops->gc_thresh) 1468 net->ipv6.ip6_rt_gc_expire = rt_gc_timeout>>1; 1469 out: 1470 net->ipv6.ip6_rt_gc_expire -= net->ipv6.ip6_rt_gc_expire>>rt_elasticity; 1471 return entries > rt_max_size; 1472 } 1473 1474 /* 1475 * 1476 */ 1477 1478 int ip6_route_add(struct fib6_config *cfg) 1479 { 1480 int err; 1481 struct net *net = cfg->fc_nlinfo.nl_net; 1482 struct rt6_info *rt = NULL; 1483 struct net_device *dev = NULL; 1484 struct inet6_dev *idev = NULL; 1485 struct fib6_table *table; 1486 int addr_type; 1487 1488 if (cfg->fc_dst_len > 128 || cfg->fc_src_len > 128) 1489 return -EINVAL; 1490 #ifndef CONFIG_IPV6_SUBTREES 1491 if (cfg->fc_src_len) 1492 return -EINVAL; 1493 #endif 1494 if (cfg->fc_ifindex) { 1495 err = -ENODEV; 1496 dev = dev_get_by_index(net, cfg->fc_ifindex); 1497 if (!dev) 1498 goto out; 1499 idev = in6_dev_get(dev); 1500 if (!idev) 1501 goto out; 1502 } 1503 1504 if (cfg->fc_metric == 0) 1505 cfg->fc_metric = IP6_RT_PRIO_USER; 1506 1507 err = -ENOBUFS; 1508 if (cfg->fc_nlinfo.nlh && 1509 !(cfg->fc_nlinfo.nlh->nlmsg_flags & NLM_F_CREATE)) { 1510 table = fib6_get_table(net, cfg->fc_table); 1511 if (!table) { 1512 pr_warn("NLM_F_CREATE should be specified when creating new route\n"); 1513 table = fib6_new_table(net, cfg->fc_table); 1514 } 1515 } else { 1516 table = fib6_new_table(net, cfg->fc_table); 1517 } 1518 1519 if (!table) 1520 goto out; 1521 1522 rt = ip6_dst_alloc(net, NULL, (cfg->fc_flags & RTF_ADDRCONF) ? 0 : DST_NOCOUNT, table); 1523 1524 if (!rt) { 1525 err = -ENOMEM; 1526 goto out; 1527 } 1528 1529 if (cfg->fc_flags & RTF_EXPIRES) 1530 rt6_set_expires(rt, jiffies + 1531 clock_t_to_jiffies(cfg->fc_expires)); 1532 else 1533 rt6_clean_expires(rt); 1534 1535 if (cfg->fc_protocol == RTPROT_UNSPEC) 1536 cfg->fc_protocol = RTPROT_BOOT; 1537 rt->rt6i_protocol = cfg->fc_protocol; 1538 1539 addr_type = ipv6_addr_type(&cfg->fc_dst); 1540 1541 if (addr_type & IPV6_ADDR_MULTICAST) 1542 rt->dst.input = ip6_mc_input; 1543 else if (cfg->fc_flags & RTF_LOCAL) 1544 rt->dst.input = ip6_input; 1545 else 1546 rt->dst.input = ip6_forward; 1547 1548 rt->dst.output = ip6_output; 1549 1550 ipv6_addr_prefix(&rt->rt6i_dst.addr, &cfg->fc_dst, cfg->fc_dst_len); 1551 rt->rt6i_dst.plen = cfg->fc_dst_len; 1552 if (rt->rt6i_dst.plen == 128) { 1553 rt->dst.flags |= DST_HOST; 1554 dst_metrics_set_force_overwrite(&rt->dst); 1555 } 1556 1557 #ifdef CONFIG_IPV6_SUBTREES 1558 ipv6_addr_prefix(&rt->rt6i_src.addr, &cfg->fc_src, cfg->fc_src_len); 1559 rt->rt6i_src.plen = cfg->fc_src_len; 1560 #endif 1561 1562 rt->rt6i_metric = cfg->fc_metric; 1563 1564 /* We cannot add true routes via loopback here, 1565 they would result in kernel looping; promote them to reject routes 1566 */ 1567 if ((cfg->fc_flags & RTF_REJECT) || 1568 (dev && (dev->flags & IFF_LOOPBACK) && 1569 !(addr_type & IPV6_ADDR_LOOPBACK) && 1570 !(cfg->fc_flags & RTF_LOCAL))) { 1571 /* hold loopback dev/idev if we haven't done so. */ 1572 if (dev != net->loopback_dev) { 1573 if (dev) { 1574 dev_put(dev); 1575 in6_dev_put(idev); 1576 } 1577 dev = net->loopback_dev; 1578 dev_hold(dev); 1579 idev = in6_dev_get(dev); 1580 if (!idev) { 1581 err = -ENODEV; 1582 goto out; 1583 } 1584 } 1585 rt->rt6i_flags = RTF_REJECT|RTF_NONEXTHOP; 1586 switch (cfg->fc_type) { 1587 case RTN_BLACKHOLE: 1588 rt->dst.error = -EINVAL; 1589 rt->dst.output = dst_discard_sk; 1590 rt->dst.input = dst_discard; 1591 break; 1592 case RTN_PROHIBIT: 1593 rt->dst.error = -EACCES; 1594 rt->dst.output = ip6_pkt_prohibit_out; 1595 rt->dst.input = ip6_pkt_prohibit; 1596 break; 1597 case RTN_THROW: 1598 default: 1599 rt->dst.error = (cfg->fc_type == RTN_THROW) ? -EAGAIN 1600 : -ENETUNREACH; 1601 rt->dst.output = ip6_pkt_discard_out; 1602 rt->dst.input = ip6_pkt_discard; 1603 break; 1604 } 1605 goto install_route; 1606 } 1607 1608 if (cfg->fc_flags & RTF_GATEWAY) { 1609 const struct in6_addr *gw_addr; 1610 int gwa_type; 1611 1612 gw_addr = &cfg->fc_gateway; 1613 rt->rt6i_gateway = *gw_addr; 1614 gwa_type = ipv6_addr_type(gw_addr); 1615 1616 if (gwa_type != (IPV6_ADDR_LINKLOCAL|IPV6_ADDR_UNICAST)) { 1617 struct rt6_info *grt; 1618 1619 /* IPv6 strictly inhibits using not link-local 1620 addresses as nexthop address. 1621 Otherwise, router will not able to send redirects. 1622 It is very good, but in some (rare!) circumstances 1623 (SIT, PtP, NBMA NOARP links) it is handy to allow 1624 some exceptions. --ANK 1625 */ 1626 err = -EINVAL; 1627 if (!(gwa_type & IPV6_ADDR_UNICAST)) 1628 goto out; 1629 1630 grt = rt6_lookup(net, gw_addr, NULL, cfg->fc_ifindex, 1); 1631 1632 err = -EHOSTUNREACH; 1633 if (!grt) 1634 goto out; 1635 if (dev) { 1636 if (dev != grt->dst.dev) { 1637 ip6_rt_put(grt); 1638 goto out; 1639 } 1640 } else { 1641 dev = grt->dst.dev; 1642 idev = grt->rt6i_idev; 1643 dev_hold(dev); 1644 in6_dev_hold(grt->rt6i_idev); 1645 } 1646 if (!(grt->rt6i_flags & RTF_GATEWAY)) 1647 err = 0; 1648 ip6_rt_put(grt); 1649 1650 if (err) 1651 goto out; 1652 } 1653 err = -EINVAL; 1654 if (!dev || (dev->flags & IFF_LOOPBACK)) 1655 goto out; 1656 } 1657 1658 err = -ENODEV; 1659 if (!dev) 1660 goto out; 1661 1662 if (!ipv6_addr_any(&cfg->fc_prefsrc)) { 1663 if (!ipv6_chk_addr(net, &cfg->fc_prefsrc, dev, 0)) { 1664 err = -EINVAL; 1665 goto out; 1666 } 1667 rt->rt6i_prefsrc.addr = cfg->fc_prefsrc; 1668 rt->rt6i_prefsrc.plen = 128; 1669 } else 1670 rt->rt6i_prefsrc.plen = 0; 1671 1672 rt->rt6i_flags = cfg->fc_flags; 1673 1674 install_route: 1675 rt->dst.dev = dev; 1676 rt->rt6i_idev = idev; 1677 rt->rt6i_table = table; 1678 1679 cfg->fc_nlinfo.nl_net = dev_net(dev); 1680 1681 return __ip6_ins_rt(rt, &cfg->fc_nlinfo, cfg->fc_mx, cfg->fc_mx_len); 1682 1683 out: 1684 if (dev) 1685 dev_put(dev); 1686 if (idev) 1687 in6_dev_put(idev); 1688 if (rt) 1689 dst_free(&rt->dst); 1690 return err; 1691 } 1692 1693 static int __ip6_del_rt(struct rt6_info *rt, struct nl_info *info) 1694 { 1695 int err; 1696 struct fib6_table *table; 1697 struct net *net = dev_net(rt->dst.dev); 1698 1699 if (rt == net->ipv6.ip6_null_entry) { 1700 err = -ENOENT; 1701 goto out; 1702 } 1703 1704 table = rt->rt6i_table; 1705 write_lock_bh(&table->tb6_lock); 1706 err = fib6_del(rt, info); 1707 write_unlock_bh(&table->tb6_lock); 1708 1709 out: 1710 ip6_rt_put(rt); 1711 return err; 1712 } 1713 1714 int ip6_del_rt(struct rt6_info *rt) 1715 { 1716 struct nl_info info = { 1717 .nl_net = dev_net(rt->dst.dev), 1718 }; 1719 return __ip6_del_rt(rt, &info); 1720 } 1721 1722 static int ip6_route_del(struct fib6_config *cfg) 1723 { 1724 struct fib6_table *table; 1725 struct fib6_node *fn; 1726 struct rt6_info *rt; 1727 int err = -ESRCH; 1728 1729 table = fib6_get_table(cfg->fc_nlinfo.nl_net, cfg->fc_table); 1730 if (!table) 1731 return err; 1732 1733 read_lock_bh(&table->tb6_lock); 1734 1735 fn = fib6_locate(&table->tb6_root, 1736 &cfg->fc_dst, cfg->fc_dst_len, 1737 &cfg->fc_src, cfg->fc_src_len); 1738 1739 if (fn) { 1740 for (rt = fn->leaf; rt; rt = rt->dst.rt6_next) { 1741 if (cfg->fc_ifindex && 1742 (!rt->dst.dev || 1743 rt->dst.dev->ifindex != cfg->fc_ifindex)) 1744 continue; 1745 if (cfg->fc_flags & RTF_GATEWAY && 1746 !ipv6_addr_equal(&cfg->fc_gateway, &rt->rt6i_gateway)) 1747 continue; 1748 if (cfg->fc_metric && cfg->fc_metric != rt->rt6i_metric) 1749 continue; 1750 dst_hold(&rt->dst); 1751 read_unlock_bh(&table->tb6_lock); 1752 1753 return __ip6_del_rt(rt, &cfg->fc_nlinfo); 1754 } 1755 } 1756 read_unlock_bh(&table->tb6_lock); 1757 1758 return err; 1759 } 1760 1761 static void rt6_do_redirect(struct dst_entry *dst, struct sock *sk, struct sk_buff *skb) 1762 { 1763 struct net *net = dev_net(skb->dev); 1764 struct netevent_redirect netevent; 1765 struct rt6_info *rt, *nrt = NULL; 1766 struct ndisc_options ndopts; 1767 struct inet6_dev *in6_dev; 1768 struct neighbour *neigh; 1769 struct rd_msg *msg; 1770 int optlen, on_link; 1771 u8 *lladdr; 1772 1773 optlen = skb_tail_pointer(skb) - skb_transport_header(skb); 1774 optlen -= sizeof(*msg); 1775 1776 if (optlen < 0) { 1777 net_dbg_ratelimited("rt6_do_redirect: packet too short\n"); 1778 return; 1779 } 1780 1781 msg = (struct rd_msg *)icmp6_hdr(skb); 1782 1783 if (ipv6_addr_is_multicast(&msg->dest)) { 1784 net_dbg_ratelimited("rt6_do_redirect: destination address is multicast\n"); 1785 return; 1786 } 1787 1788 on_link = 0; 1789 if (ipv6_addr_equal(&msg->dest, &msg->target)) { 1790 on_link = 1; 1791 } else if (ipv6_addr_type(&msg->target) != 1792 (IPV6_ADDR_UNICAST|IPV6_ADDR_LINKLOCAL)) { 1793 net_dbg_ratelimited("rt6_do_redirect: target address is not link-local unicast\n"); 1794 return; 1795 } 1796 1797 in6_dev = __in6_dev_get(skb->dev); 1798 if (!in6_dev) 1799 return; 1800 if (in6_dev->cnf.forwarding || !in6_dev->cnf.accept_redirects) 1801 return; 1802 1803 /* RFC2461 8.1: 1804 * The IP source address of the Redirect MUST be the same as the current 1805 * first-hop router for the specified ICMP Destination Address. 1806 */ 1807 1808 if (!ndisc_parse_options(msg->opt, optlen, &ndopts)) { 1809 net_dbg_ratelimited("rt6_redirect: invalid ND options\n"); 1810 return; 1811 } 1812 1813 lladdr = NULL; 1814 if (ndopts.nd_opts_tgt_lladdr) { 1815 lladdr = ndisc_opt_addr_data(ndopts.nd_opts_tgt_lladdr, 1816 skb->dev); 1817 if (!lladdr) { 1818 net_dbg_ratelimited("rt6_redirect: invalid link-layer address length\n"); 1819 return; 1820 } 1821 } 1822 1823 rt = (struct rt6_info *) dst; 1824 if (rt == net->ipv6.ip6_null_entry) { 1825 net_dbg_ratelimited("rt6_redirect: source isn't a valid nexthop for redirect target\n"); 1826 return; 1827 } 1828 1829 /* Redirect received -> path was valid. 1830 * Look, redirects are sent only in response to data packets, 1831 * so that this nexthop apparently is reachable. --ANK 1832 */ 1833 dst_confirm(&rt->dst); 1834 1835 neigh = __neigh_lookup(&nd_tbl, &msg->target, skb->dev, 1); 1836 if (!neigh) 1837 return; 1838 1839 /* 1840 * We have finally decided to accept it. 1841 */ 1842 1843 neigh_update(neigh, lladdr, NUD_STALE, 1844 NEIGH_UPDATE_F_WEAK_OVERRIDE| 1845 NEIGH_UPDATE_F_OVERRIDE| 1846 (on_link ? 0 : (NEIGH_UPDATE_F_OVERRIDE_ISROUTER| 1847 NEIGH_UPDATE_F_ISROUTER)) 1848 ); 1849 1850 nrt = ip6_rt_copy(rt, &msg->dest); 1851 if (!nrt) 1852 goto out; 1853 1854 nrt->rt6i_flags = RTF_GATEWAY|RTF_UP|RTF_DYNAMIC|RTF_CACHE; 1855 if (on_link) 1856 nrt->rt6i_flags &= ~RTF_GATEWAY; 1857 1858 nrt->rt6i_gateway = *(struct in6_addr *)neigh->primary_key; 1859 1860 if (ip6_ins_rt(nrt)) 1861 goto out; 1862 1863 netevent.old = &rt->dst; 1864 netevent.new = &nrt->dst; 1865 netevent.daddr = &msg->dest; 1866 netevent.neigh = neigh; 1867 call_netevent_notifiers(NETEVENT_REDIRECT, &netevent); 1868 1869 if (rt->rt6i_flags & RTF_CACHE) { 1870 rt = (struct rt6_info *) dst_clone(&rt->dst); 1871 ip6_del_rt(rt); 1872 } 1873 1874 out: 1875 neigh_release(neigh); 1876 } 1877 1878 /* 1879 * Misc support functions 1880 */ 1881 1882 static struct rt6_info *ip6_rt_copy(struct rt6_info *ort, 1883 const struct in6_addr *dest) 1884 { 1885 struct net *net = dev_net(ort->dst.dev); 1886 struct rt6_info *rt = ip6_dst_alloc(net, ort->dst.dev, 0, 1887 ort->rt6i_table); 1888 1889 if (rt) { 1890 rt->dst.input = ort->dst.input; 1891 rt->dst.output = ort->dst.output; 1892 rt->dst.flags |= DST_HOST; 1893 1894 rt->rt6i_dst.addr = *dest; 1895 rt->rt6i_dst.plen = 128; 1896 dst_copy_metrics(&rt->dst, &ort->dst); 1897 rt->dst.error = ort->dst.error; 1898 rt->rt6i_idev = ort->rt6i_idev; 1899 if (rt->rt6i_idev) 1900 in6_dev_hold(rt->rt6i_idev); 1901 rt->dst.lastuse = jiffies; 1902 1903 if (ort->rt6i_flags & RTF_GATEWAY) 1904 rt->rt6i_gateway = ort->rt6i_gateway; 1905 else 1906 rt->rt6i_gateway = *dest; 1907 rt->rt6i_flags = ort->rt6i_flags; 1908 rt6_set_from(rt, ort); 1909 rt->rt6i_metric = 0; 1910 1911 #ifdef CONFIG_IPV6_SUBTREES 1912 memcpy(&rt->rt6i_src, &ort->rt6i_src, sizeof(struct rt6key)); 1913 #endif 1914 memcpy(&rt->rt6i_prefsrc, &ort->rt6i_prefsrc, sizeof(struct rt6key)); 1915 rt->rt6i_table = ort->rt6i_table; 1916 } 1917 return rt; 1918 } 1919 1920 #ifdef CONFIG_IPV6_ROUTE_INFO 1921 static struct rt6_info *rt6_get_route_info(struct net *net, 1922 const struct in6_addr *prefix, int prefixlen, 1923 const struct in6_addr *gwaddr, int ifindex) 1924 { 1925 struct fib6_node *fn; 1926 struct rt6_info *rt = NULL; 1927 struct fib6_table *table; 1928 1929 table = fib6_get_table(net, RT6_TABLE_INFO); 1930 if (!table) 1931 return NULL; 1932 1933 read_lock_bh(&table->tb6_lock); 1934 fn = fib6_locate(&table->tb6_root, prefix, prefixlen, NULL, 0); 1935 if (!fn) 1936 goto out; 1937 1938 for (rt = fn->leaf; rt; rt = rt->dst.rt6_next) { 1939 if (rt->dst.dev->ifindex != ifindex) 1940 continue; 1941 if ((rt->rt6i_flags & (RTF_ROUTEINFO|RTF_GATEWAY)) != (RTF_ROUTEINFO|RTF_GATEWAY)) 1942 continue; 1943 if (!ipv6_addr_equal(&rt->rt6i_gateway, gwaddr)) 1944 continue; 1945 dst_hold(&rt->dst); 1946 break; 1947 } 1948 out: 1949 read_unlock_bh(&table->tb6_lock); 1950 return rt; 1951 } 1952 1953 static struct rt6_info *rt6_add_route_info(struct net *net, 1954 const struct in6_addr *prefix, int prefixlen, 1955 const struct in6_addr *gwaddr, int ifindex, 1956 unsigned int pref) 1957 { 1958 struct fib6_config cfg = { 1959 .fc_table = RT6_TABLE_INFO, 1960 .fc_metric = IP6_RT_PRIO_USER, 1961 .fc_ifindex = ifindex, 1962 .fc_dst_len = prefixlen, 1963 .fc_flags = RTF_GATEWAY | RTF_ADDRCONF | RTF_ROUTEINFO | 1964 RTF_UP | RTF_PREF(pref), 1965 .fc_nlinfo.portid = 0, 1966 .fc_nlinfo.nlh = NULL, 1967 .fc_nlinfo.nl_net = net, 1968 }; 1969 1970 cfg.fc_dst = *prefix; 1971 cfg.fc_gateway = *gwaddr; 1972 1973 /* We should treat it as a default route if prefix length is 0. */ 1974 if (!prefixlen) 1975 cfg.fc_flags |= RTF_DEFAULT; 1976 1977 ip6_route_add(&cfg); 1978 1979 return rt6_get_route_info(net, prefix, prefixlen, gwaddr, ifindex); 1980 } 1981 #endif 1982 1983 struct rt6_info *rt6_get_dflt_router(const struct in6_addr *addr, struct net_device *dev) 1984 { 1985 struct rt6_info *rt; 1986 struct fib6_table *table; 1987 1988 table = fib6_get_table(dev_net(dev), RT6_TABLE_DFLT); 1989 if (!table) 1990 return NULL; 1991 1992 read_lock_bh(&table->tb6_lock); 1993 for (rt = table->tb6_root.leaf; rt; rt = rt->dst.rt6_next) { 1994 if (dev == rt->dst.dev && 1995 ((rt->rt6i_flags & (RTF_ADDRCONF | RTF_DEFAULT)) == (RTF_ADDRCONF | RTF_DEFAULT)) && 1996 ipv6_addr_equal(&rt->rt6i_gateway, addr)) 1997 break; 1998 } 1999 if (rt) 2000 dst_hold(&rt->dst); 2001 read_unlock_bh(&table->tb6_lock); 2002 return rt; 2003 } 2004 2005 struct rt6_info *rt6_add_dflt_router(const struct in6_addr *gwaddr, 2006 struct net_device *dev, 2007 unsigned int pref) 2008 { 2009 struct fib6_config cfg = { 2010 .fc_table = RT6_TABLE_DFLT, 2011 .fc_metric = IP6_RT_PRIO_USER, 2012 .fc_ifindex = dev->ifindex, 2013 .fc_flags = RTF_GATEWAY | RTF_ADDRCONF | RTF_DEFAULT | 2014 RTF_UP | RTF_EXPIRES | RTF_PREF(pref), 2015 .fc_nlinfo.portid = 0, 2016 .fc_nlinfo.nlh = NULL, 2017 .fc_nlinfo.nl_net = dev_net(dev), 2018 }; 2019 2020 cfg.fc_gateway = *gwaddr; 2021 2022 ip6_route_add(&cfg); 2023 2024 return rt6_get_dflt_router(gwaddr, dev); 2025 } 2026 2027 void rt6_purge_dflt_routers(struct net *net) 2028 { 2029 struct rt6_info *rt; 2030 struct fib6_table *table; 2031 2032 /* NOTE: Keep consistent with rt6_get_dflt_router */ 2033 table = fib6_get_table(net, RT6_TABLE_DFLT); 2034 if (!table) 2035 return; 2036 2037 restart: 2038 read_lock_bh(&table->tb6_lock); 2039 for (rt = table->tb6_root.leaf; rt; rt = rt->dst.rt6_next) { 2040 if (rt->rt6i_flags & (RTF_DEFAULT | RTF_ADDRCONF) && 2041 (!rt->rt6i_idev || rt->rt6i_idev->cnf.accept_ra != 2)) { 2042 dst_hold(&rt->dst); 2043 read_unlock_bh(&table->tb6_lock); 2044 ip6_del_rt(rt); 2045 goto restart; 2046 } 2047 } 2048 read_unlock_bh(&table->tb6_lock); 2049 } 2050 2051 static void rtmsg_to_fib6_config(struct net *net, 2052 struct in6_rtmsg *rtmsg, 2053 struct fib6_config *cfg) 2054 { 2055 memset(cfg, 0, sizeof(*cfg)); 2056 2057 cfg->fc_table = RT6_TABLE_MAIN; 2058 cfg->fc_ifindex = rtmsg->rtmsg_ifindex; 2059 cfg->fc_metric = rtmsg->rtmsg_metric; 2060 cfg->fc_expires = rtmsg->rtmsg_info; 2061 cfg->fc_dst_len = rtmsg->rtmsg_dst_len; 2062 cfg->fc_src_len = rtmsg->rtmsg_src_len; 2063 cfg->fc_flags = rtmsg->rtmsg_flags; 2064 2065 cfg->fc_nlinfo.nl_net = net; 2066 2067 cfg->fc_dst = rtmsg->rtmsg_dst; 2068 cfg->fc_src = rtmsg->rtmsg_src; 2069 cfg->fc_gateway = rtmsg->rtmsg_gateway; 2070 } 2071 2072 int ipv6_route_ioctl(struct net *net, unsigned int cmd, void __user *arg) 2073 { 2074 struct fib6_config cfg; 2075 struct in6_rtmsg rtmsg; 2076 int err; 2077 2078 switch (cmd) { 2079 case SIOCADDRT: /* Add a route */ 2080 case SIOCDELRT: /* Delete a route */ 2081 if (!ns_capable(net->user_ns, CAP_NET_ADMIN)) 2082 return -EPERM; 2083 err = copy_from_user(&rtmsg, arg, 2084 sizeof(struct in6_rtmsg)); 2085 if (err) 2086 return -EFAULT; 2087 2088 rtmsg_to_fib6_config(net, &rtmsg, &cfg); 2089 2090 rtnl_lock(); 2091 switch (cmd) { 2092 case SIOCADDRT: 2093 err = ip6_route_add(&cfg); 2094 break; 2095 case SIOCDELRT: 2096 err = ip6_route_del(&cfg); 2097 break; 2098 default: 2099 err = -EINVAL; 2100 } 2101 rtnl_unlock(); 2102 2103 return err; 2104 } 2105 2106 return -EINVAL; 2107 } 2108 2109 /* 2110 * Drop the packet on the floor 2111 */ 2112 2113 static int ip6_pkt_drop(struct sk_buff *skb, u8 code, int ipstats_mib_noroutes) 2114 { 2115 int type; 2116 struct dst_entry *dst = skb_dst(skb); 2117 switch (ipstats_mib_noroutes) { 2118 case IPSTATS_MIB_INNOROUTES: 2119 type = ipv6_addr_type(&ipv6_hdr(skb)->daddr); 2120 if (type == IPV6_ADDR_ANY) { 2121 IP6_INC_STATS(dev_net(dst->dev), ip6_dst_idev(dst), 2122 IPSTATS_MIB_INADDRERRORS); 2123 break; 2124 } 2125 /* FALLTHROUGH */ 2126 case IPSTATS_MIB_OUTNOROUTES: 2127 IP6_INC_STATS(dev_net(dst->dev), ip6_dst_idev(dst), 2128 ipstats_mib_noroutes); 2129 break; 2130 } 2131 icmpv6_send(skb, ICMPV6_DEST_UNREACH, code, 0); 2132 kfree_skb(skb); 2133 return 0; 2134 } 2135 2136 static int ip6_pkt_discard(struct sk_buff *skb) 2137 { 2138 return ip6_pkt_drop(skb, ICMPV6_NOROUTE, IPSTATS_MIB_INNOROUTES); 2139 } 2140 2141 static int ip6_pkt_discard_out(struct sock *sk, struct sk_buff *skb) 2142 { 2143 skb->dev = skb_dst(skb)->dev; 2144 return ip6_pkt_drop(skb, ICMPV6_NOROUTE, IPSTATS_MIB_OUTNOROUTES); 2145 } 2146 2147 static int ip6_pkt_prohibit(struct sk_buff *skb) 2148 { 2149 return ip6_pkt_drop(skb, ICMPV6_ADM_PROHIBITED, IPSTATS_MIB_INNOROUTES); 2150 } 2151 2152 static int ip6_pkt_prohibit_out(struct sock *sk, struct sk_buff *skb) 2153 { 2154 skb->dev = skb_dst(skb)->dev; 2155 return ip6_pkt_drop(skb, ICMPV6_ADM_PROHIBITED, IPSTATS_MIB_OUTNOROUTES); 2156 } 2157 2158 /* 2159 * Allocate a dst for local (unicast / anycast) address. 2160 */ 2161 2162 struct rt6_info *addrconf_dst_alloc(struct inet6_dev *idev, 2163 const struct in6_addr *addr, 2164 bool anycast) 2165 { 2166 struct net *net = dev_net(idev->dev); 2167 struct rt6_info *rt = ip6_dst_alloc(net, net->loopback_dev, 2168 DST_NOCOUNT, NULL); 2169 if (!rt) 2170 return ERR_PTR(-ENOMEM); 2171 2172 in6_dev_hold(idev); 2173 2174 rt->dst.flags |= DST_HOST; 2175 rt->dst.input = ip6_input; 2176 rt->dst.output = ip6_output; 2177 rt->rt6i_idev = idev; 2178 2179 rt->rt6i_flags = RTF_UP | RTF_NONEXTHOP; 2180 if (anycast) 2181 rt->rt6i_flags |= RTF_ANYCAST; 2182 else 2183 rt->rt6i_flags |= RTF_LOCAL; 2184 2185 rt->rt6i_gateway = *addr; 2186 rt->rt6i_dst.addr = *addr; 2187 rt->rt6i_dst.plen = 128; 2188 rt->rt6i_table = fib6_get_table(net, RT6_TABLE_LOCAL); 2189 2190 atomic_set(&rt->dst.__refcnt, 1); 2191 2192 return rt; 2193 } 2194 2195 int ip6_route_get_saddr(struct net *net, 2196 struct rt6_info *rt, 2197 const struct in6_addr *daddr, 2198 unsigned int prefs, 2199 struct in6_addr *saddr) 2200 { 2201 struct inet6_dev *idev = ip6_dst_idev((struct dst_entry *)rt); 2202 int err = 0; 2203 if (rt->rt6i_prefsrc.plen) 2204 *saddr = rt->rt6i_prefsrc.addr; 2205 else 2206 err = ipv6_dev_get_saddr(net, idev ? idev->dev : NULL, 2207 daddr, prefs, saddr); 2208 return err; 2209 } 2210 2211 /* remove deleted ip from prefsrc entries */ 2212 struct arg_dev_net_ip { 2213 struct net_device *dev; 2214 struct net *net; 2215 struct in6_addr *addr; 2216 }; 2217 2218 static int fib6_remove_prefsrc(struct rt6_info *rt, void *arg) 2219 { 2220 struct net_device *dev = ((struct arg_dev_net_ip *)arg)->dev; 2221 struct net *net = ((struct arg_dev_net_ip *)arg)->net; 2222 struct in6_addr *addr = ((struct arg_dev_net_ip *)arg)->addr; 2223 2224 if (((void *)rt->dst.dev == dev || !dev) && 2225 rt != net->ipv6.ip6_null_entry && 2226 ipv6_addr_equal(addr, &rt->rt6i_prefsrc.addr)) { 2227 /* remove prefsrc entry */ 2228 rt->rt6i_prefsrc.plen = 0; 2229 } 2230 return 0; 2231 } 2232 2233 void rt6_remove_prefsrc(struct inet6_ifaddr *ifp) 2234 { 2235 struct net *net = dev_net(ifp->idev->dev); 2236 struct arg_dev_net_ip adni = { 2237 .dev = ifp->idev->dev, 2238 .net = net, 2239 .addr = &ifp->addr, 2240 }; 2241 fib6_clean_all(net, fib6_remove_prefsrc, &adni); 2242 } 2243 2244 #define RTF_RA_ROUTER (RTF_ADDRCONF | RTF_DEFAULT | RTF_GATEWAY) 2245 #define RTF_CACHE_GATEWAY (RTF_GATEWAY | RTF_CACHE) 2246 2247 /* Remove routers and update dst entries when gateway turn into host. */ 2248 static int fib6_clean_tohost(struct rt6_info *rt, void *arg) 2249 { 2250 struct in6_addr *gateway = (struct in6_addr *)arg; 2251 2252 if ((((rt->rt6i_flags & RTF_RA_ROUTER) == RTF_RA_ROUTER) || 2253 ((rt->rt6i_flags & RTF_CACHE_GATEWAY) == RTF_CACHE_GATEWAY)) && 2254 ipv6_addr_equal(gateway, &rt->rt6i_gateway)) { 2255 return -1; 2256 } 2257 return 0; 2258 } 2259 2260 void rt6_clean_tohost(struct net *net, struct in6_addr *gateway) 2261 { 2262 fib6_clean_all(net, fib6_clean_tohost, gateway); 2263 } 2264 2265 struct arg_dev_net { 2266 struct net_device *dev; 2267 struct net *net; 2268 }; 2269 2270 static int fib6_ifdown(struct rt6_info *rt, void *arg) 2271 { 2272 const struct arg_dev_net *adn = arg; 2273 const struct net_device *dev = adn->dev; 2274 2275 if ((rt->dst.dev == dev || !dev) && 2276 rt != adn->net->ipv6.ip6_null_entry) 2277 return -1; 2278 2279 return 0; 2280 } 2281 2282 void rt6_ifdown(struct net *net, struct net_device *dev) 2283 { 2284 struct arg_dev_net adn = { 2285 .dev = dev, 2286 .net = net, 2287 }; 2288 2289 fib6_clean_all(net, fib6_ifdown, &adn); 2290 icmp6_clean_all(fib6_ifdown, &adn); 2291 } 2292 2293 struct rt6_mtu_change_arg { 2294 struct net_device *dev; 2295 unsigned int mtu; 2296 }; 2297 2298 static int rt6_mtu_change_route(struct rt6_info *rt, void *p_arg) 2299 { 2300 struct rt6_mtu_change_arg *arg = (struct rt6_mtu_change_arg *) p_arg; 2301 struct inet6_dev *idev; 2302 2303 /* In IPv6 pmtu discovery is not optional, 2304 so that RTAX_MTU lock cannot disable it. 2305 We still use this lock to block changes 2306 caused by addrconf/ndisc. 2307 */ 2308 2309 idev = __in6_dev_get(arg->dev); 2310 if (!idev) 2311 return 0; 2312 2313 /* For administrative MTU increase, there is no way to discover 2314 IPv6 PMTU increase, so PMTU increase should be updated here. 2315 Since RFC 1981 doesn't include administrative MTU increase 2316 update PMTU increase is a MUST. (i.e. jumbo frame) 2317 */ 2318 /* 2319 If new MTU is less than route PMTU, this new MTU will be the 2320 lowest MTU in the path, update the route PMTU to reflect PMTU 2321 decreases; if new MTU is greater than route PMTU, and the 2322 old MTU is the lowest MTU in the path, update the route PMTU 2323 to reflect the increase. In this case if the other nodes' MTU 2324 also have the lowest MTU, TOO BIG MESSAGE will be lead to 2325 PMTU discouvery. 2326 */ 2327 if (rt->dst.dev == arg->dev && 2328 !dst_metric_locked(&rt->dst, RTAX_MTU) && 2329 (dst_mtu(&rt->dst) >= arg->mtu || 2330 (dst_mtu(&rt->dst) < arg->mtu && 2331 dst_mtu(&rt->dst) == idev->cnf.mtu6))) { 2332 dst_metric_set(&rt->dst, RTAX_MTU, arg->mtu); 2333 } 2334 return 0; 2335 } 2336 2337 void rt6_mtu_change(struct net_device *dev, unsigned int mtu) 2338 { 2339 struct rt6_mtu_change_arg arg = { 2340 .dev = dev, 2341 .mtu = mtu, 2342 }; 2343 2344 fib6_clean_all(dev_net(dev), rt6_mtu_change_route, &arg); 2345 } 2346 2347 static const struct nla_policy rtm_ipv6_policy[RTA_MAX+1] = { 2348 [RTA_GATEWAY] = { .len = sizeof(struct in6_addr) }, 2349 [RTA_OIF] = { .type = NLA_U32 }, 2350 [RTA_IIF] = { .type = NLA_U32 }, 2351 [RTA_PRIORITY] = { .type = NLA_U32 }, 2352 [RTA_METRICS] = { .type = NLA_NESTED }, 2353 [RTA_MULTIPATH] = { .len = sizeof(struct rtnexthop) }, 2354 }; 2355 2356 static int rtm_to_fib6_config(struct sk_buff *skb, struct nlmsghdr *nlh, 2357 struct fib6_config *cfg) 2358 { 2359 struct rtmsg *rtm; 2360 struct nlattr *tb[RTA_MAX+1]; 2361 int err; 2362 2363 err = nlmsg_parse(nlh, sizeof(*rtm), tb, RTA_MAX, rtm_ipv6_policy); 2364 if (err < 0) 2365 goto errout; 2366 2367 err = -EINVAL; 2368 rtm = nlmsg_data(nlh); 2369 memset(cfg, 0, sizeof(*cfg)); 2370 2371 cfg->fc_table = rtm->rtm_table; 2372 cfg->fc_dst_len = rtm->rtm_dst_len; 2373 cfg->fc_src_len = rtm->rtm_src_len; 2374 cfg->fc_flags = RTF_UP; 2375 cfg->fc_protocol = rtm->rtm_protocol; 2376 cfg->fc_type = rtm->rtm_type; 2377 2378 if (rtm->rtm_type == RTN_UNREACHABLE || 2379 rtm->rtm_type == RTN_BLACKHOLE || 2380 rtm->rtm_type == RTN_PROHIBIT || 2381 rtm->rtm_type == RTN_THROW) 2382 cfg->fc_flags |= RTF_REJECT; 2383 2384 if (rtm->rtm_type == RTN_LOCAL) 2385 cfg->fc_flags |= RTF_LOCAL; 2386 2387 cfg->fc_nlinfo.portid = NETLINK_CB(skb).portid; 2388 cfg->fc_nlinfo.nlh = nlh; 2389 cfg->fc_nlinfo.nl_net = sock_net(skb->sk); 2390 2391 if (tb[RTA_GATEWAY]) { 2392 nla_memcpy(&cfg->fc_gateway, tb[RTA_GATEWAY], 16); 2393 cfg->fc_flags |= RTF_GATEWAY; 2394 } 2395 2396 if (tb[RTA_DST]) { 2397 int plen = (rtm->rtm_dst_len + 7) >> 3; 2398 2399 if (nla_len(tb[RTA_DST]) < plen) 2400 goto errout; 2401 2402 nla_memcpy(&cfg->fc_dst, tb[RTA_DST], plen); 2403 } 2404 2405 if (tb[RTA_SRC]) { 2406 int plen = (rtm->rtm_src_len + 7) >> 3; 2407 2408 if (nla_len(tb[RTA_SRC]) < plen) 2409 goto errout; 2410 2411 nla_memcpy(&cfg->fc_src, tb[RTA_SRC], plen); 2412 } 2413 2414 if (tb[RTA_PREFSRC]) 2415 nla_memcpy(&cfg->fc_prefsrc, tb[RTA_PREFSRC], 16); 2416 2417 if (tb[RTA_OIF]) 2418 cfg->fc_ifindex = nla_get_u32(tb[RTA_OIF]); 2419 2420 if (tb[RTA_PRIORITY]) 2421 cfg->fc_metric = nla_get_u32(tb[RTA_PRIORITY]); 2422 2423 if (tb[RTA_METRICS]) { 2424 cfg->fc_mx = nla_data(tb[RTA_METRICS]); 2425 cfg->fc_mx_len = nla_len(tb[RTA_METRICS]); 2426 } 2427 2428 if (tb[RTA_TABLE]) 2429 cfg->fc_table = nla_get_u32(tb[RTA_TABLE]); 2430 2431 if (tb[RTA_MULTIPATH]) { 2432 cfg->fc_mp = nla_data(tb[RTA_MULTIPATH]); 2433 cfg->fc_mp_len = nla_len(tb[RTA_MULTIPATH]); 2434 } 2435 2436 err = 0; 2437 errout: 2438 return err; 2439 } 2440 2441 static int ip6_route_multipath(struct fib6_config *cfg, int add) 2442 { 2443 struct fib6_config r_cfg; 2444 struct rtnexthop *rtnh; 2445 int remaining; 2446 int attrlen; 2447 int err = 0, last_err = 0; 2448 2449 beginning: 2450 rtnh = (struct rtnexthop *)cfg->fc_mp; 2451 remaining = cfg->fc_mp_len; 2452 2453 /* Parse a Multipath Entry */ 2454 while (rtnh_ok(rtnh, remaining)) { 2455 memcpy(&r_cfg, cfg, sizeof(*cfg)); 2456 if (rtnh->rtnh_ifindex) 2457 r_cfg.fc_ifindex = rtnh->rtnh_ifindex; 2458 2459 attrlen = rtnh_attrlen(rtnh); 2460 if (attrlen > 0) { 2461 struct nlattr *nla, *attrs = rtnh_attrs(rtnh); 2462 2463 nla = nla_find(attrs, attrlen, RTA_GATEWAY); 2464 if (nla) { 2465 nla_memcpy(&r_cfg.fc_gateway, nla, 16); 2466 r_cfg.fc_flags |= RTF_GATEWAY; 2467 } 2468 } 2469 err = add ? ip6_route_add(&r_cfg) : ip6_route_del(&r_cfg); 2470 if (err) { 2471 last_err = err; 2472 /* If we are trying to remove a route, do not stop the 2473 * loop when ip6_route_del() fails (because next hop is 2474 * already gone), we should try to remove all next hops. 2475 */ 2476 if (add) { 2477 /* If add fails, we should try to delete all 2478 * next hops that have been already added. 2479 */ 2480 add = 0; 2481 goto beginning; 2482 } 2483 } 2484 /* Because each route is added like a single route we remove 2485 * this flag after the first nexthop (if there is a collision, 2486 * we have already fail to add the first nexthop: 2487 * fib6_add_rt2node() has reject it). 2488 */ 2489 cfg->fc_nlinfo.nlh->nlmsg_flags &= ~NLM_F_EXCL; 2490 rtnh = rtnh_next(rtnh, &remaining); 2491 } 2492 2493 return last_err; 2494 } 2495 2496 static int inet6_rtm_delroute(struct sk_buff *skb, struct nlmsghdr *nlh) 2497 { 2498 struct fib6_config cfg; 2499 int err; 2500 2501 err = rtm_to_fib6_config(skb, nlh, &cfg); 2502 if (err < 0) 2503 return err; 2504 2505 if (cfg.fc_mp) 2506 return ip6_route_multipath(&cfg, 0); 2507 else 2508 return ip6_route_del(&cfg); 2509 } 2510 2511 static int inet6_rtm_newroute(struct sk_buff *skb, struct nlmsghdr *nlh) 2512 { 2513 struct fib6_config cfg; 2514 int err; 2515 2516 err = rtm_to_fib6_config(skb, nlh, &cfg); 2517 if (err < 0) 2518 return err; 2519 2520 if (cfg.fc_mp) 2521 return ip6_route_multipath(&cfg, 1); 2522 else 2523 return ip6_route_add(&cfg); 2524 } 2525 2526 static inline size_t rt6_nlmsg_size(void) 2527 { 2528 return NLMSG_ALIGN(sizeof(struct rtmsg)) 2529 + nla_total_size(16) /* RTA_SRC */ 2530 + nla_total_size(16) /* RTA_DST */ 2531 + nla_total_size(16) /* RTA_GATEWAY */ 2532 + nla_total_size(16) /* RTA_PREFSRC */ 2533 + nla_total_size(4) /* RTA_TABLE */ 2534 + nla_total_size(4) /* RTA_IIF */ 2535 + nla_total_size(4) /* RTA_OIF */ 2536 + nla_total_size(4) /* RTA_PRIORITY */ 2537 + RTAX_MAX * nla_total_size(4) /* RTA_METRICS */ 2538 + nla_total_size(sizeof(struct rta_cacheinfo)); 2539 } 2540 2541 static int rt6_fill_node(struct net *net, 2542 struct sk_buff *skb, struct rt6_info *rt, 2543 struct in6_addr *dst, struct in6_addr *src, 2544 int iif, int type, u32 portid, u32 seq, 2545 int prefix, int nowait, unsigned int flags) 2546 { 2547 struct rtmsg *rtm; 2548 struct nlmsghdr *nlh; 2549 long expires; 2550 u32 table; 2551 2552 if (prefix) { /* user wants prefix routes only */ 2553 if (!(rt->rt6i_flags & RTF_PREFIX_RT)) { 2554 /* success since this is not a prefix route */ 2555 return 1; 2556 } 2557 } 2558 2559 nlh = nlmsg_put(skb, portid, seq, type, sizeof(*rtm), flags); 2560 if (!nlh) 2561 return -EMSGSIZE; 2562 2563 rtm = nlmsg_data(nlh); 2564 rtm->rtm_family = AF_INET6; 2565 rtm->rtm_dst_len = rt->rt6i_dst.plen; 2566 rtm->rtm_src_len = rt->rt6i_src.plen; 2567 rtm->rtm_tos = 0; 2568 if (rt->rt6i_table) 2569 table = rt->rt6i_table->tb6_id; 2570 else 2571 table = RT6_TABLE_UNSPEC; 2572 rtm->rtm_table = table; 2573 if (nla_put_u32(skb, RTA_TABLE, table)) 2574 goto nla_put_failure; 2575 if (rt->rt6i_flags & RTF_REJECT) { 2576 switch (rt->dst.error) { 2577 case -EINVAL: 2578 rtm->rtm_type = RTN_BLACKHOLE; 2579 break; 2580 case -EACCES: 2581 rtm->rtm_type = RTN_PROHIBIT; 2582 break; 2583 case -EAGAIN: 2584 rtm->rtm_type = RTN_THROW; 2585 break; 2586 default: 2587 rtm->rtm_type = RTN_UNREACHABLE; 2588 break; 2589 } 2590 } 2591 else if (rt->rt6i_flags & RTF_LOCAL) 2592 rtm->rtm_type = RTN_LOCAL; 2593 else if (rt->dst.dev && (rt->dst.dev->flags & IFF_LOOPBACK)) 2594 rtm->rtm_type = RTN_LOCAL; 2595 else 2596 rtm->rtm_type = RTN_UNICAST; 2597 rtm->rtm_flags = 0; 2598 rtm->rtm_scope = RT_SCOPE_UNIVERSE; 2599 rtm->rtm_protocol = rt->rt6i_protocol; 2600 if (rt->rt6i_flags & RTF_DYNAMIC) 2601 rtm->rtm_protocol = RTPROT_REDIRECT; 2602 else if (rt->rt6i_flags & RTF_ADDRCONF) { 2603 if (rt->rt6i_flags & (RTF_DEFAULT | RTF_ROUTEINFO)) 2604 rtm->rtm_protocol = RTPROT_RA; 2605 else 2606 rtm->rtm_protocol = RTPROT_KERNEL; 2607 } 2608 2609 if (rt->rt6i_flags & RTF_CACHE) 2610 rtm->rtm_flags |= RTM_F_CLONED; 2611 2612 if (dst) { 2613 if (nla_put(skb, RTA_DST, 16, dst)) 2614 goto nla_put_failure; 2615 rtm->rtm_dst_len = 128; 2616 } else if (rtm->rtm_dst_len) 2617 if (nla_put(skb, RTA_DST, 16, &rt->rt6i_dst.addr)) 2618 goto nla_put_failure; 2619 #ifdef CONFIG_IPV6_SUBTREES 2620 if (src) { 2621 if (nla_put(skb, RTA_SRC, 16, src)) 2622 goto nla_put_failure; 2623 rtm->rtm_src_len = 128; 2624 } else if (rtm->rtm_src_len && 2625 nla_put(skb, RTA_SRC, 16, &rt->rt6i_src.addr)) 2626 goto nla_put_failure; 2627 #endif 2628 if (iif) { 2629 #ifdef CONFIG_IPV6_MROUTE 2630 if (ipv6_addr_is_multicast(&rt->rt6i_dst.addr)) { 2631 int err = ip6mr_get_route(net, skb, rtm, nowait); 2632 if (err <= 0) { 2633 if (!nowait) { 2634 if (err == 0) 2635 return 0; 2636 goto nla_put_failure; 2637 } else { 2638 if (err == -EMSGSIZE) 2639 goto nla_put_failure; 2640 } 2641 } 2642 } else 2643 #endif 2644 if (nla_put_u32(skb, RTA_IIF, iif)) 2645 goto nla_put_failure; 2646 } else if (dst) { 2647 struct in6_addr saddr_buf; 2648 if (ip6_route_get_saddr(net, rt, dst, 0, &saddr_buf) == 0 && 2649 nla_put(skb, RTA_PREFSRC, 16, &saddr_buf)) 2650 goto nla_put_failure; 2651 } 2652 2653 if (rt->rt6i_prefsrc.plen) { 2654 struct in6_addr saddr_buf; 2655 saddr_buf = rt->rt6i_prefsrc.addr; 2656 if (nla_put(skb, RTA_PREFSRC, 16, &saddr_buf)) 2657 goto nla_put_failure; 2658 } 2659 2660 if (rtnetlink_put_metrics(skb, dst_metrics_ptr(&rt->dst)) < 0) 2661 goto nla_put_failure; 2662 2663 if (rt->rt6i_flags & RTF_GATEWAY) { 2664 if (nla_put(skb, RTA_GATEWAY, 16, &rt->rt6i_gateway) < 0) 2665 goto nla_put_failure; 2666 } 2667 2668 if (rt->dst.dev && 2669 nla_put_u32(skb, RTA_OIF, rt->dst.dev->ifindex)) 2670 goto nla_put_failure; 2671 if (nla_put_u32(skb, RTA_PRIORITY, rt->rt6i_metric)) 2672 goto nla_put_failure; 2673 2674 expires = (rt->rt6i_flags & RTF_EXPIRES) ? rt->dst.expires - jiffies : 0; 2675 2676 if (rtnl_put_cacheinfo(skb, &rt->dst, 0, expires, rt->dst.error) < 0) 2677 goto nla_put_failure; 2678 2679 return nlmsg_end(skb, nlh); 2680 2681 nla_put_failure: 2682 nlmsg_cancel(skb, nlh); 2683 return -EMSGSIZE; 2684 } 2685 2686 int rt6_dump_route(struct rt6_info *rt, void *p_arg) 2687 { 2688 struct rt6_rtnl_dump_arg *arg = (struct rt6_rtnl_dump_arg *) p_arg; 2689 int prefix; 2690 2691 if (nlmsg_len(arg->cb->nlh) >= sizeof(struct rtmsg)) { 2692 struct rtmsg *rtm = nlmsg_data(arg->cb->nlh); 2693 prefix = (rtm->rtm_flags & RTM_F_PREFIX) != 0; 2694 } else 2695 prefix = 0; 2696 2697 return rt6_fill_node(arg->net, 2698 arg->skb, rt, NULL, NULL, 0, RTM_NEWROUTE, 2699 NETLINK_CB(arg->cb->skb).portid, arg->cb->nlh->nlmsg_seq, 2700 prefix, 0, NLM_F_MULTI); 2701 } 2702 2703 static int inet6_rtm_getroute(struct sk_buff *in_skb, struct nlmsghdr *nlh) 2704 { 2705 struct net *net = sock_net(in_skb->sk); 2706 struct nlattr *tb[RTA_MAX+1]; 2707 struct rt6_info *rt; 2708 struct sk_buff *skb; 2709 struct rtmsg *rtm; 2710 struct flowi6 fl6; 2711 int err, iif = 0, oif = 0; 2712 2713 err = nlmsg_parse(nlh, sizeof(*rtm), tb, RTA_MAX, rtm_ipv6_policy); 2714 if (err < 0) 2715 goto errout; 2716 2717 err = -EINVAL; 2718 memset(&fl6, 0, sizeof(fl6)); 2719 2720 if (tb[RTA_SRC]) { 2721 if (nla_len(tb[RTA_SRC]) < sizeof(struct in6_addr)) 2722 goto errout; 2723 2724 fl6.saddr = *(struct in6_addr *)nla_data(tb[RTA_SRC]); 2725 } 2726 2727 if (tb[RTA_DST]) { 2728 if (nla_len(tb[RTA_DST]) < sizeof(struct in6_addr)) 2729 goto errout; 2730 2731 fl6.daddr = *(struct in6_addr *)nla_data(tb[RTA_DST]); 2732 } 2733 2734 if (tb[RTA_IIF]) 2735 iif = nla_get_u32(tb[RTA_IIF]); 2736 2737 if (tb[RTA_OIF]) 2738 oif = nla_get_u32(tb[RTA_OIF]); 2739 2740 if (tb[RTA_MARK]) 2741 fl6.flowi6_mark = nla_get_u32(tb[RTA_MARK]); 2742 2743 if (iif) { 2744 struct net_device *dev; 2745 int flags = 0; 2746 2747 dev = __dev_get_by_index(net, iif); 2748 if (!dev) { 2749 err = -ENODEV; 2750 goto errout; 2751 } 2752 2753 fl6.flowi6_iif = iif; 2754 2755 if (!ipv6_addr_any(&fl6.saddr)) 2756 flags |= RT6_LOOKUP_F_HAS_SADDR; 2757 2758 rt = (struct rt6_info *)ip6_route_input_lookup(net, dev, &fl6, 2759 flags); 2760 } else { 2761 fl6.flowi6_oif = oif; 2762 2763 rt = (struct rt6_info *)ip6_route_output(net, NULL, &fl6); 2764 } 2765 2766 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL); 2767 if (!skb) { 2768 ip6_rt_put(rt); 2769 err = -ENOBUFS; 2770 goto errout; 2771 } 2772 2773 /* Reserve room for dummy headers, this skb can pass 2774 through good chunk of routing engine. 2775 */ 2776 skb_reset_mac_header(skb); 2777 skb_reserve(skb, MAX_HEADER + sizeof(struct ipv6hdr)); 2778 2779 skb_dst_set(skb, &rt->dst); 2780 2781 err = rt6_fill_node(net, skb, rt, &fl6.daddr, &fl6.saddr, iif, 2782 RTM_NEWROUTE, NETLINK_CB(in_skb).portid, 2783 nlh->nlmsg_seq, 0, 0, 0); 2784 if (err < 0) { 2785 kfree_skb(skb); 2786 goto errout; 2787 } 2788 2789 err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid); 2790 errout: 2791 return err; 2792 } 2793 2794 void inet6_rt_notify(int event, struct rt6_info *rt, struct nl_info *info) 2795 { 2796 struct sk_buff *skb; 2797 struct net *net = info->nl_net; 2798 u32 seq; 2799 int err; 2800 2801 err = -ENOBUFS; 2802 seq = info->nlh ? info->nlh->nlmsg_seq : 0; 2803 2804 skb = nlmsg_new(rt6_nlmsg_size(), gfp_any()); 2805 if (!skb) 2806 goto errout; 2807 2808 err = rt6_fill_node(net, skb, rt, NULL, NULL, 0, 2809 event, info->portid, seq, 0, 0, 0); 2810 if (err < 0) { 2811 /* -EMSGSIZE implies BUG in rt6_nlmsg_size() */ 2812 WARN_ON(err == -EMSGSIZE); 2813 kfree_skb(skb); 2814 goto errout; 2815 } 2816 rtnl_notify(skb, net, info->portid, RTNLGRP_IPV6_ROUTE, 2817 info->nlh, gfp_any()); 2818 return; 2819 errout: 2820 if (err < 0) 2821 rtnl_set_sk_err(net, RTNLGRP_IPV6_ROUTE, err); 2822 } 2823 2824 static int ip6_route_dev_notify(struct notifier_block *this, 2825 unsigned long event, void *ptr) 2826 { 2827 struct net_device *dev = netdev_notifier_info_to_dev(ptr); 2828 struct net *net = dev_net(dev); 2829 2830 if (event == NETDEV_REGISTER && (dev->flags & IFF_LOOPBACK)) { 2831 net->ipv6.ip6_null_entry->dst.dev = dev; 2832 net->ipv6.ip6_null_entry->rt6i_idev = in6_dev_get(dev); 2833 #ifdef CONFIG_IPV6_MULTIPLE_TABLES 2834 net->ipv6.ip6_prohibit_entry->dst.dev = dev; 2835 net->ipv6.ip6_prohibit_entry->rt6i_idev = in6_dev_get(dev); 2836 net->ipv6.ip6_blk_hole_entry->dst.dev = dev; 2837 net->ipv6.ip6_blk_hole_entry->rt6i_idev = in6_dev_get(dev); 2838 #endif 2839 } 2840 2841 return NOTIFY_OK; 2842 } 2843 2844 /* 2845 * /proc 2846 */ 2847 2848 #ifdef CONFIG_PROC_FS 2849 2850 static const struct file_operations ipv6_route_proc_fops = { 2851 .owner = THIS_MODULE, 2852 .open = ipv6_route_open, 2853 .read = seq_read, 2854 .llseek = seq_lseek, 2855 .release = seq_release_net, 2856 }; 2857 2858 static int rt6_stats_seq_show(struct seq_file *seq, void *v) 2859 { 2860 struct net *net = (struct net *)seq->private; 2861 seq_printf(seq, "%04x %04x %04x %04x %04x %04x %04x\n", 2862 net->ipv6.rt6_stats->fib_nodes, 2863 net->ipv6.rt6_stats->fib_route_nodes, 2864 net->ipv6.rt6_stats->fib_rt_alloc, 2865 net->ipv6.rt6_stats->fib_rt_entries, 2866 net->ipv6.rt6_stats->fib_rt_cache, 2867 dst_entries_get_slow(&net->ipv6.ip6_dst_ops), 2868 net->ipv6.rt6_stats->fib_discarded_routes); 2869 2870 return 0; 2871 } 2872 2873 static int rt6_stats_seq_open(struct inode *inode, struct file *file) 2874 { 2875 return single_open_net(inode, file, rt6_stats_seq_show); 2876 } 2877 2878 static const struct file_operations rt6_stats_seq_fops = { 2879 .owner = THIS_MODULE, 2880 .open = rt6_stats_seq_open, 2881 .read = seq_read, 2882 .llseek = seq_lseek, 2883 .release = single_release_net, 2884 }; 2885 #endif /* CONFIG_PROC_FS */ 2886 2887 #ifdef CONFIG_SYSCTL 2888 2889 static 2890 int ipv6_sysctl_rtcache_flush(struct ctl_table *ctl, int write, 2891 void __user *buffer, size_t *lenp, loff_t *ppos) 2892 { 2893 struct net *net; 2894 int delay; 2895 if (!write) 2896 return -EINVAL; 2897 2898 net = (struct net *)ctl->extra1; 2899 delay = net->ipv6.sysctl.flush_delay; 2900 proc_dointvec(ctl, write, buffer, lenp, ppos); 2901 fib6_run_gc(delay <= 0 ? 0 : (unsigned long)delay, net, delay > 0); 2902 return 0; 2903 } 2904 2905 struct ctl_table ipv6_route_table_template[] = { 2906 { 2907 .procname = "flush", 2908 .data = &init_net.ipv6.sysctl.flush_delay, 2909 .maxlen = sizeof(int), 2910 .mode = 0200, 2911 .proc_handler = ipv6_sysctl_rtcache_flush 2912 }, 2913 { 2914 .procname = "gc_thresh", 2915 .data = &ip6_dst_ops_template.gc_thresh, 2916 .maxlen = sizeof(int), 2917 .mode = 0644, 2918 .proc_handler = proc_dointvec, 2919 }, 2920 { 2921 .procname = "max_size", 2922 .data = &init_net.ipv6.sysctl.ip6_rt_max_size, 2923 .maxlen = sizeof(int), 2924 .mode = 0644, 2925 .proc_handler = proc_dointvec, 2926 }, 2927 { 2928 .procname = "gc_min_interval", 2929 .data = &init_net.ipv6.sysctl.ip6_rt_gc_min_interval, 2930 .maxlen = sizeof(int), 2931 .mode = 0644, 2932 .proc_handler = proc_dointvec_jiffies, 2933 }, 2934 { 2935 .procname = "gc_timeout", 2936 .data = &init_net.ipv6.sysctl.ip6_rt_gc_timeout, 2937 .maxlen = sizeof(int), 2938 .mode = 0644, 2939 .proc_handler = proc_dointvec_jiffies, 2940 }, 2941 { 2942 .procname = "gc_interval", 2943 .data = &init_net.ipv6.sysctl.ip6_rt_gc_interval, 2944 .maxlen = sizeof(int), 2945 .mode = 0644, 2946 .proc_handler = proc_dointvec_jiffies, 2947 }, 2948 { 2949 .procname = "gc_elasticity", 2950 .data = &init_net.ipv6.sysctl.ip6_rt_gc_elasticity, 2951 .maxlen = sizeof(int), 2952 .mode = 0644, 2953 .proc_handler = proc_dointvec, 2954 }, 2955 { 2956 .procname = "mtu_expires", 2957 .data = &init_net.ipv6.sysctl.ip6_rt_mtu_expires, 2958 .maxlen = sizeof(int), 2959 .mode = 0644, 2960 .proc_handler = proc_dointvec_jiffies, 2961 }, 2962 { 2963 .procname = "min_adv_mss", 2964 .data = &init_net.ipv6.sysctl.ip6_rt_min_advmss, 2965 .maxlen = sizeof(int), 2966 .mode = 0644, 2967 .proc_handler = proc_dointvec, 2968 }, 2969 { 2970 .procname = "gc_min_interval_ms", 2971 .data = &init_net.ipv6.sysctl.ip6_rt_gc_min_interval, 2972 .maxlen = sizeof(int), 2973 .mode = 0644, 2974 .proc_handler = proc_dointvec_ms_jiffies, 2975 }, 2976 { } 2977 }; 2978 2979 struct ctl_table * __net_init ipv6_route_sysctl_init(struct net *net) 2980 { 2981 struct ctl_table *table; 2982 2983 table = kmemdup(ipv6_route_table_template, 2984 sizeof(ipv6_route_table_template), 2985 GFP_KERNEL); 2986 2987 if (table) { 2988 table[0].data = &net->ipv6.sysctl.flush_delay; 2989 table[0].extra1 = net; 2990 table[1].data = &net->ipv6.ip6_dst_ops.gc_thresh; 2991 table[2].data = &net->ipv6.sysctl.ip6_rt_max_size; 2992 table[3].data = &net->ipv6.sysctl.ip6_rt_gc_min_interval; 2993 table[4].data = &net->ipv6.sysctl.ip6_rt_gc_timeout; 2994 table[5].data = &net->ipv6.sysctl.ip6_rt_gc_interval; 2995 table[6].data = &net->ipv6.sysctl.ip6_rt_gc_elasticity; 2996 table[7].data = &net->ipv6.sysctl.ip6_rt_mtu_expires; 2997 table[8].data = &net->ipv6.sysctl.ip6_rt_min_advmss; 2998 table[9].data = &net->ipv6.sysctl.ip6_rt_gc_min_interval; 2999 3000 /* Don't export sysctls to unprivileged users */ 3001 if (net->user_ns != &init_user_ns) 3002 table[0].procname = NULL; 3003 } 3004 3005 return table; 3006 } 3007 #endif 3008 3009 static int __net_init ip6_route_net_init(struct net *net) 3010 { 3011 int ret = -ENOMEM; 3012 3013 memcpy(&net->ipv6.ip6_dst_ops, &ip6_dst_ops_template, 3014 sizeof(net->ipv6.ip6_dst_ops)); 3015 3016 if (dst_entries_init(&net->ipv6.ip6_dst_ops) < 0) 3017 goto out_ip6_dst_ops; 3018 3019 net->ipv6.ip6_null_entry = kmemdup(&ip6_null_entry_template, 3020 sizeof(*net->ipv6.ip6_null_entry), 3021 GFP_KERNEL); 3022 if (!net->ipv6.ip6_null_entry) 3023 goto out_ip6_dst_entries; 3024 net->ipv6.ip6_null_entry->dst.path = 3025 (struct dst_entry *)net->ipv6.ip6_null_entry; 3026 net->ipv6.ip6_null_entry->dst.ops = &net->ipv6.ip6_dst_ops; 3027 dst_init_metrics(&net->ipv6.ip6_null_entry->dst, 3028 ip6_template_metrics, true); 3029 3030 #ifdef CONFIG_IPV6_MULTIPLE_TABLES 3031 net->ipv6.ip6_prohibit_entry = kmemdup(&ip6_prohibit_entry_template, 3032 sizeof(*net->ipv6.ip6_prohibit_entry), 3033 GFP_KERNEL); 3034 if (!net->ipv6.ip6_prohibit_entry) 3035 goto out_ip6_null_entry; 3036 net->ipv6.ip6_prohibit_entry->dst.path = 3037 (struct dst_entry *)net->ipv6.ip6_prohibit_entry; 3038 net->ipv6.ip6_prohibit_entry->dst.ops = &net->ipv6.ip6_dst_ops; 3039 dst_init_metrics(&net->ipv6.ip6_prohibit_entry->dst, 3040 ip6_template_metrics, true); 3041 3042 net->ipv6.ip6_blk_hole_entry = kmemdup(&ip6_blk_hole_entry_template, 3043 sizeof(*net->ipv6.ip6_blk_hole_entry), 3044 GFP_KERNEL); 3045 if (!net->ipv6.ip6_blk_hole_entry) 3046 goto out_ip6_prohibit_entry; 3047 net->ipv6.ip6_blk_hole_entry->dst.path = 3048 (struct dst_entry *)net->ipv6.ip6_blk_hole_entry; 3049 net->ipv6.ip6_blk_hole_entry->dst.ops = &net->ipv6.ip6_dst_ops; 3050 dst_init_metrics(&net->ipv6.ip6_blk_hole_entry->dst, 3051 ip6_template_metrics, true); 3052 #endif 3053 3054 net->ipv6.sysctl.flush_delay = 0; 3055 net->ipv6.sysctl.ip6_rt_max_size = 4096; 3056 net->ipv6.sysctl.ip6_rt_gc_min_interval = HZ / 2; 3057 net->ipv6.sysctl.ip6_rt_gc_timeout = 60*HZ; 3058 net->ipv6.sysctl.ip6_rt_gc_interval = 30*HZ; 3059 net->ipv6.sysctl.ip6_rt_gc_elasticity = 9; 3060 net->ipv6.sysctl.ip6_rt_mtu_expires = 10*60*HZ; 3061 net->ipv6.sysctl.ip6_rt_min_advmss = IPV6_MIN_MTU - 20 - 40; 3062 3063 net->ipv6.ip6_rt_gc_expire = 30*HZ; 3064 3065 ret = 0; 3066 out: 3067 return ret; 3068 3069 #ifdef CONFIG_IPV6_MULTIPLE_TABLES 3070 out_ip6_prohibit_entry: 3071 kfree(net->ipv6.ip6_prohibit_entry); 3072 out_ip6_null_entry: 3073 kfree(net->ipv6.ip6_null_entry); 3074 #endif 3075 out_ip6_dst_entries: 3076 dst_entries_destroy(&net->ipv6.ip6_dst_ops); 3077 out_ip6_dst_ops: 3078 goto out; 3079 } 3080 3081 static void __net_exit ip6_route_net_exit(struct net *net) 3082 { 3083 kfree(net->ipv6.ip6_null_entry); 3084 #ifdef CONFIG_IPV6_MULTIPLE_TABLES 3085 kfree(net->ipv6.ip6_prohibit_entry); 3086 kfree(net->ipv6.ip6_blk_hole_entry); 3087 #endif 3088 dst_entries_destroy(&net->ipv6.ip6_dst_ops); 3089 } 3090 3091 static int __net_init ip6_route_net_init_late(struct net *net) 3092 { 3093 #ifdef CONFIG_PROC_FS 3094 proc_create("ipv6_route", 0, net->proc_net, &ipv6_route_proc_fops); 3095 proc_create("rt6_stats", S_IRUGO, net->proc_net, &rt6_stats_seq_fops); 3096 #endif 3097 return 0; 3098 } 3099 3100 static void __net_exit ip6_route_net_exit_late(struct net *net) 3101 { 3102 #ifdef CONFIG_PROC_FS 3103 remove_proc_entry("ipv6_route", net->proc_net); 3104 remove_proc_entry("rt6_stats", net->proc_net); 3105 #endif 3106 } 3107 3108 static struct pernet_operations ip6_route_net_ops = { 3109 .init = ip6_route_net_init, 3110 .exit = ip6_route_net_exit, 3111 }; 3112 3113 static int __net_init ipv6_inetpeer_init(struct net *net) 3114 { 3115 struct inet_peer_base *bp = kmalloc(sizeof(*bp), GFP_KERNEL); 3116 3117 if (!bp) 3118 return -ENOMEM; 3119 inet_peer_base_init(bp); 3120 net->ipv6.peers = bp; 3121 return 0; 3122 } 3123 3124 static void __net_exit ipv6_inetpeer_exit(struct net *net) 3125 { 3126 struct inet_peer_base *bp = net->ipv6.peers; 3127 3128 net->ipv6.peers = NULL; 3129 inetpeer_invalidate_tree(bp); 3130 kfree(bp); 3131 } 3132 3133 static struct pernet_operations ipv6_inetpeer_ops = { 3134 .init = ipv6_inetpeer_init, 3135 .exit = ipv6_inetpeer_exit, 3136 }; 3137 3138 static struct pernet_operations ip6_route_net_late_ops = { 3139 .init = ip6_route_net_init_late, 3140 .exit = ip6_route_net_exit_late, 3141 }; 3142 3143 static struct notifier_block ip6_route_dev_notifier = { 3144 .notifier_call = ip6_route_dev_notify, 3145 .priority = 0, 3146 }; 3147 3148 int __init ip6_route_init(void) 3149 { 3150 int ret; 3151 3152 ret = -ENOMEM; 3153 ip6_dst_ops_template.kmem_cachep = 3154 kmem_cache_create("ip6_dst_cache", sizeof(struct rt6_info), 0, 3155 SLAB_HWCACHE_ALIGN, NULL); 3156 if (!ip6_dst_ops_template.kmem_cachep) 3157 goto out; 3158 3159 ret = dst_entries_init(&ip6_dst_blackhole_ops); 3160 if (ret) 3161 goto out_kmem_cache; 3162 3163 ret = register_pernet_subsys(&ipv6_inetpeer_ops); 3164 if (ret) 3165 goto out_dst_entries; 3166 3167 ret = register_pernet_subsys(&ip6_route_net_ops); 3168 if (ret) 3169 goto out_register_inetpeer; 3170 3171 ip6_dst_blackhole_ops.kmem_cachep = ip6_dst_ops_template.kmem_cachep; 3172 3173 /* Registering of the loopback is done before this portion of code, 3174 * the loopback reference in rt6_info will not be taken, do it 3175 * manually for init_net */ 3176 init_net.ipv6.ip6_null_entry->dst.dev = init_net.loopback_dev; 3177 init_net.ipv6.ip6_null_entry->rt6i_idev = in6_dev_get(init_net.loopback_dev); 3178 #ifdef CONFIG_IPV6_MULTIPLE_TABLES 3179 init_net.ipv6.ip6_prohibit_entry->dst.dev = init_net.loopback_dev; 3180 init_net.ipv6.ip6_prohibit_entry->rt6i_idev = in6_dev_get(init_net.loopback_dev); 3181 init_net.ipv6.ip6_blk_hole_entry->dst.dev = init_net.loopback_dev; 3182 init_net.ipv6.ip6_blk_hole_entry->rt6i_idev = in6_dev_get(init_net.loopback_dev); 3183 #endif 3184 ret = fib6_init(); 3185 if (ret) 3186 goto out_register_subsys; 3187 3188 ret = xfrm6_init(); 3189 if (ret) 3190 goto out_fib6_init; 3191 3192 ret = fib6_rules_init(); 3193 if (ret) 3194 goto xfrm6_init; 3195 3196 ret = register_pernet_subsys(&ip6_route_net_late_ops); 3197 if (ret) 3198 goto fib6_rules_init; 3199 3200 ret = -ENOBUFS; 3201 if (__rtnl_register(PF_INET6, RTM_NEWROUTE, inet6_rtm_newroute, NULL, NULL) || 3202 __rtnl_register(PF_INET6, RTM_DELROUTE, inet6_rtm_delroute, NULL, NULL) || 3203 __rtnl_register(PF_INET6, RTM_GETROUTE, inet6_rtm_getroute, NULL, NULL)) 3204 goto out_register_late_subsys; 3205 3206 ret = register_netdevice_notifier(&ip6_route_dev_notifier); 3207 if (ret) 3208 goto out_register_late_subsys; 3209 3210 out: 3211 return ret; 3212 3213 out_register_late_subsys: 3214 unregister_pernet_subsys(&ip6_route_net_late_ops); 3215 fib6_rules_init: 3216 fib6_rules_cleanup(); 3217 xfrm6_init: 3218 xfrm6_fini(); 3219 out_fib6_init: 3220 fib6_gc_cleanup(); 3221 out_register_subsys: 3222 unregister_pernet_subsys(&ip6_route_net_ops); 3223 out_register_inetpeer: 3224 unregister_pernet_subsys(&ipv6_inetpeer_ops); 3225 out_dst_entries: 3226 dst_entries_destroy(&ip6_dst_blackhole_ops); 3227 out_kmem_cache: 3228 kmem_cache_destroy(ip6_dst_ops_template.kmem_cachep); 3229 goto out; 3230 } 3231 3232 void ip6_route_cleanup(void) 3233 { 3234 unregister_netdevice_notifier(&ip6_route_dev_notifier); 3235 unregister_pernet_subsys(&ip6_route_net_late_ops); 3236 fib6_rules_cleanup(); 3237 xfrm6_fini(); 3238 fib6_gc_cleanup(); 3239 unregister_pernet_subsys(&ipv6_inetpeer_ops); 3240 unregister_pernet_subsys(&ip6_route_net_ops); 3241 dst_entries_destroy(&ip6_dst_blackhole_ops); 3242 kmem_cache_destroy(ip6_dst_ops_template.kmem_cachep); 3243 } 3244