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 #include <linux/capability.h> 28 #include <linux/errno.h> 29 #include <linux/types.h> 30 #include <linux/times.h> 31 #include <linux/socket.h> 32 #include <linux/sockios.h> 33 #include <linux/net.h> 34 #include <linux/route.h> 35 #include <linux/netdevice.h> 36 #include <linux/in6.h> 37 #include <linux/mroute6.h> 38 #include <linux/init.h> 39 #include <linux/if_arp.h> 40 #include <linux/proc_fs.h> 41 #include <linux/seq_file.h> 42 #include <linux/nsproxy.h> 43 #include <net/net_namespace.h> 44 #include <net/snmp.h> 45 #include <net/ipv6.h> 46 #include <net/ip6_fib.h> 47 #include <net/ip6_route.h> 48 #include <net/ndisc.h> 49 #include <net/addrconf.h> 50 #include <net/tcp.h> 51 #include <linux/rtnetlink.h> 52 #include <net/dst.h> 53 #include <net/xfrm.h> 54 #include <net/netevent.h> 55 #include <net/netlink.h> 56 57 #include <asm/uaccess.h> 58 59 #ifdef CONFIG_SYSCTL 60 #include <linux/sysctl.h> 61 #endif 62 63 /* Set to 3 to get tracing. */ 64 #define RT6_DEBUG 2 65 66 #if RT6_DEBUG >= 3 67 #define RDBG(x) printk x 68 #define RT6_TRACE(x...) printk(KERN_DEBUG x) 69 #else 70 #define RDBG(x) 71 #define RT6_TRACE(x...) do { ; } while (0) 72 #endif 73 74 #define CLONE_OFFLINK_ROUTE 0 75 76 static struct rt6_info * ip6_rt_copy(struct rt6_info *ort); 77 static struct dst_entry *ip6_dst_check(struct dst_entry *dst, u32 cookie); 78 static struct dst_entry *ip6_negative_advice(struct dst_entry *); 79 static void ip6_dst_destroy(struct dst_entry *); 80 static void ip6_dst_ifdown(struct dst_entry *, 81 struct net_device *dev, int how); 82 static int ip6_dst_gc(struct dst_ops *ops); 83 84 static int ip6_pkt_discard(struct sk_buff *skb); 85 static int ip6_pkt_discard_out(struct sk_buff *skb); 86 static void ip6_link_failure(struct sk_buff *skb); 87 static void ip6_rt_update_pmtu(struct dst_entry *dst, u32 mtu); 88 89 #ifdef CONFIG_IPV6_ROUTE_INFO 90 static struct rt6_info *rt6_add_route_info(struct net *net, 91 struct in6_addr *prefix, int prefixlen, 92 struct in6_addr *gwaddr, int ifindex, 93 unsigned pref); 94 static struct rt6_info *rt6_get_route_info(struct net *net, 95 struct in6_addr *prefix, int prefixlen, 96 struct in6_addr *gwaddr, int ifindex); 97 #endif 98 99 static struct dst_ops ip6_dst_ops_template = { 100 .family = AF_INET6, 101 .protocol = __constant_htons(ETH_P_IPV6), 102 .gc = ip6_dst_gc, 103 .gc_thresh = 1024, 104 .check = ip6_dst_check, 105 .destroy = ip6_dst_destroy, 106 .ifdown = ip6_dst_ifdown, 107 .negative_advice = ip6_negative_advice, 108 .link_failure = ip6_link_failure, 109 .update_pmtu = ip6_rt_update_pmtu, 110 .local_out = __ip6_local_out, 111 .entry_size = sizeof(struct rt6_info), 112 .entries = ATOMIC_INIT(0), 113 }; 114 115 static void ip6_rt_blackhole_update_pmtu(struct dst_entry *dst, u32 mtu) 116 { 117 } 118 119 static struct dst_ops ip6_dst_blackhole_ops = { 120 .family = AF_INET6, 121 .protocol = __constant_htons(ETH_P_IPV6), 122 .destroy = ip6_dst_destroy, 123 .check = ip6_dst_check, 124 .update_pmtu = ip6_rt_blackhole_update_pmtu, 125 .entry_size = sizeof(struct rt6_info), 126 .entries = ATOMIC_INIT(0), 127 }; 128 129 static struct rt6_info ip6_null_entry_template = { 130 .u = { 131 .dst = { 132 .__refcnt = ATOMIC_INIT(1), 133 .__use = 1, 134 .obsolete = -1, 135 .error = -ENETUNREACH, 136 .metrics = { [RTAX_HOPLIMIT - 1] = 255, }, 137 .input = ip6_pkt_discard, 138 .output = ip6_pkt_discard_out, 139 } 140 }, 141 .rt6i_flags = (RTF_REJECT | RTF_NONEXTHOP), 142 .rt6i_metric = ~(u32) 0, 143 .rt6i_ref = ATOMIC_INIT(1), 144 }; 145 146 #ifdef CONFIG_IPV6_MULTIPLE_TABLES 147 148 static int ip6_pkt_prohibit(struct sk_buff *skb); 149 static int ip6_pkt_prohibit_out(struct sk_buff *skb); 150 151 static struct rt6_info ip6_prohibit_entry_template = { 152 .u = { 153 .dst = { 154 .__refcnt = ATOMIC_INIT(1), 155 .__use = 1, 156 .obsolete = -1, 157 .error = -EACCES, 158 .metrics = { [RTAX_HOPLIMIT - 1] = 255, }, 159 .input = ip6_pkt_prohibit, 160 .output = ip6_pkt_prohibit_out, 161 } 162 }, 163 .rt6i_flags = (RTF_REJECT | RTF_NONEXTHOP), 164 .rt6i_metric = ~(u32) 0, 165 .rt6i_ref = ATOMIC_INIT(1), 166 }; 167 168 static struct rt6_info ip6_blk_hole_entry_template = { 169 .u = { 170 .dst = { 171 .__refcnt = ATOMIC_INIT(1), 172 .__use = 1, 173 .obsolete = -1, 174 .error = -EINVAL, 175 .metrics = { [RTAX_HOPLIMIT - 1] = 255, }, 176 .input = dst_discard, 177 .output = dst_discard, 178 } 179 }, 180 .rt6i_flags = (RTF_REJECT | RTF_NONEXTHOP), 181 .rt6i_metric = ~(u32) 0, 182 .rt6i_ref = ATOMIC_INIT(1), 183 }; 184 185 #endif 186 187 /* allocate dst with ip6_dst_ops */ 188 static inline struct rt6_info *ip6_dst_alloc(struct dst_ops *ops) 189 { 190 return (struct rt6_info *)dst_alloc(ops); 191 } 192 193 static void ip6_dst_destroy(struct dst_entry *dst) 194 { 195 struct rt6_info *rt = (struct rt6_info *)dst; 196 struct inet6_dev *idev = rt->rt6i_idev; 197 198 if (idev != NULL) { 199 rt->rt6i_idev = NULL; 200 in6_dev_put(idev); 201 } 202 } 203 204 static void ip6_dst_ifdown(struct dst_entry *dst, struct net_device *dev, 205 int how) 206 { 207 struct rt6_info *rt = (struct rt6_info *)dst; 208 struct inet6_dev *idev = rt->rt6i_idev; 209 struct net_device *loopback_dev = 210 dev_net(dev)->loopback_dev; 211 212 if (dev != loopback_dev && idev != NULL && idev->dev == dev) { 213 struct inet6_dev *loopback_idev = 214 in6_dev_get(loopback_dev); 215 if (loopback_idev != NULL) { 216 rt->rt6i_idev = loopback_idev; 217 in6_dev_put(idev); 218 } 219 } 220 } 221 222 static __inline__ int rt6_check_expired(const struct rt6_info *rt) 223 { 224 return (rt->rt6i_flags & RTF_EXPIRES && 225 time_after(jiffies, rt->rt6i_expires)); 226 } 227 228 static inline int rt6_need_strict(struct in6_addr *daddr) 229 { 230 return (ipv6_addr_type(daddr) & 231 (IPV6_ADDR_MULTICAST | IPV6_ADDR_LINKLOCAL | IPV6_ADDR_LOOPBACK)); 232 } 233 234 /* 235 * Route lookup. Any table->tb6_lock is implied. 236 */ 237 238 static inline struct rt6_info *rt6_device_match(struct net *net, 239 struct rt6_info *rt, 240 struct in6_addr *saddr, 241 int oif, 242 int flags) 243 { 244 struct rt6_info *local = NULL; 245 struct rt6_info *sprt; 246 247 if (!oif && ipv6_addr_any(saddr)) 248 goto out; 249 250 for (sprt = rt; sprt; sprt = sprt->u.dst.rt6_next) { 251 struct net_device *dev = sprt->rt6i_dev; 252 253 if (oif) { 254 if (dev->ifindex == oif) 255 return sprt; 256 if (dev->flags & IFF_LOOPBACK) { 257 if (sprt->rt6i_idev == NULL || 258 sprt->rt6i_idev->dev->ifindex != oif) { 259 if (flags & RT6_LOOKUP_F_IFACE && oif) 260 continue; 261 if (local && (!oif || 262 local->rt6i_idev->dev->ifindex == oif)) 263 continue; 264 } 265 local = sprt; 266 } 267 } else { 268 if (ipv6_chk_addr(net, saddr, dev, 269 flags & RT6_LOOKUP_F_IFACE)) 270 return sprt; 271 } 272 } 273 274 if (oif) { 275 if (local) 276 return local; 277 278 if (flags & RT6_LOOKUP_F_IFACE) 279 return net->ipv6.ip6_null_entry; 280 } 281 out: 282 return rt; 283 } 284 285 #ifdef CONFIG_IPV6_ROUTER_PREF 286 static void rt6_probe(struct rt6_info *rt) 287 { 288 struct neighbour *neigh = rt ? rt->rt6i_nexthop : NULL; 289 /* 290 * Okay, this does not seem to be appropriate 291 * for now, however, we need to check if it 292 * is really so; aka Router Reachability Probing. 293 * 294 * Router Reachability Probe MUST be rate-limited 295 * to no more than one per minute. 296 */ 297 if (!neigh || (neigh->nud_state & NUD_VALID)) 298 return; 299 read_lock_bh(&neigh->lock); 300 if (!(neigh->nud_state & NUD_VALID) && 301 time_after(jiffies, neigh->updated + rt->rt6i_idev->cnf.rtr_probe_interval)) { 302 struct in6_addr mcaddr; 303 struct in6_addr *target; 304 305 neigh->updated = jiffies; 306 read_unlock_bh(&neigh->lock); 307 308 target = (struct in6_addr *)&neigh->primary_key; 309 addrconf_addr_solict_mult(target, &mcaddr); 310 ndisc_send_ns(rt->rt6i_dev, NULL, target, &mcaddr, NULL); 311 } else 312 read_unlock_bh(&neigh->lock); 313 } 314 #else 315 static inline void rt6_probe(struct rt6_info *rt) 316 { 317 return; 318 } 319 #endif 320 321 /* 322 * Default Router Selection (RFC 2461 6.3.6) 323 */ 324 static inline int rt6_check_dev(struct rt6_info *rt, int oif) 325 { 326 struct net_device *dev = rt->rt6i_dev; 327 if (!oif || dev->ifindex == oif) 328 return 2; 329 if ((dev->flags & IFF_LOOPBACK) && 330 rt->rt6i_idev && rt->rt6i_idev->dev->ifindex == oif) 331 return 1; 332 return 0; 333 } 334 335 static inline int rt6_check_neigh(struct rt6_info *rt) 336 { 337 struct neighbour *neigh = rt->rt6i_nexthop; 338 int m; 339 if (rt->rt6i_flags & RTF_NONEXTHOP || 340 !(rt->rt6i_flags & RTF_GATEWAY)) 341 m = 1; 342 else if (neigh) { 343 read_lock_bh(&neigh->lock); 344 if (neigh->nud_state & NUD_VALID) 345 m = 2; 346 #ifdef CONFIG_IPV6_ROUTER_PREF 347 else if (neigh->nud_state & NUD_FAILED) 348 m = 0; 349 #endif 350 else 351 m = 1; 352 read_unlock_bh(&neigh->lock); 353 } else 354 m = 0; 355 return m; 356 } 357 358 static int rt6_score_route(struct rt6_info *rt, int oif, 359 int strict) 360 { 361 int m, n; 362 363 m = rt6_check_dev(rt, oif); 364 if (!m && (strict & RT6_LOOKUP_F_IFACE)) 365 return -1; 366 #ifdef CONFIG_IPV6_ROUTER_PREF 367 m |= IPV6_DECODE_PREF(IPV6_EXTRACT_PREF(rt->rt6i_flags)) << 2; 368 #endif 369 n = rt6_check_neigh(rt); 370 if (!n && (strict & RT6_LOOKUP_F_REACHABLE)) 371 return -1; 372 return m; 373 } 374 375 static struct rt6_info *find_match(struct rt6_info *rt, int oif, int strict, 376 int *mpri, struct rt6_info *match) 377 { 378 int m; 379 380 if (rt6_check_expired(rt)) 381 goto out; 382 383 m = rt6_score_route(rt, oif, strict); 384 if (m < 0) 385 goto out; 386 387 if (m > *mpri) { 388 if (strict & RT6_LOOKUP_F_REACHABLE) 389 rt6_probe(match); 390 *mpri = m; 391 match = rt; 392 } else if (strict & RT6_LOOKUP_F_REACHABLE) { 393 rt6_probe(rt); 394 } 395 396 out: 397 return match; 398 } 399 400 static struct rt6_info *find_rr_leaf(struct fib6_node *fn, 401 struct rt6_info *rr_head, 402 u32 metric, int oif, int strict) 403 { 404 struct rt6_info *rt, *match; 405 int mpri = -1; 406 407 match = NULL; 408 for (rt = rr_head; rt && rt->rt6i_metric == metric; 409 rt = rt->u.dst.rt6_next) 410 match = find_match(rt, oif, strict, &mpri, match); 411 for (rt = fn->leaf; rt && rt != rr_head && rt->rt6i_metric == metric; 412 rt = rt->u.dst.rt6_next) 413 match = find_match(rt, oif, strict, &mpri, match); 414 415 return match; 416 } 417 418 static struct rt6_info *rt6_select(struct fib6_node *fn, int oif, int strict) 419 { 420 struct rt6_info *match, *rt0; 421 struct net *net; 422 423 RT6_TRACE("%s(fn->leaf=%p, oif=%d)\n", 424 __func__, fn->leaf, oif); 425 426 rt0 = fn->rr_ptr; 427 if (!rt0) 428 fn->rr_ptr = rt0 = fn->leaf; 429 430 match = find_rr_leaf(fn, rt0, rt0->rt6i_metric, oif, strict); 431 432 if (!match && 433 (strict & RT6_LOOKUP_F_REACHABLE)) { 434 struct rt6_info *next = rt0->u.dst.rt6_next; 435 436 /* no entries matched; do round-robin */ 437 if (!next || next->rt6i_metric != rt0->rt6i_metric) 438 next = fn->leaf; 439 440 if (next != rt0) 441 fn->rr_ptr = next; 442 } 443 444 RT6_TRACE("%s() => %p\n", 445 __func__, match); 446 447 net = dev_net(rt0->rt6i_dev); 448 return (match ? match : net->ipv6.ip6_null_entry); 449 } 450 451 #ifdef CONFIG_IPV6_ROUTE_INFO 452 int rt6_route_rcv(struct net_device *dev, u8 *opt, int len, 453 struct in6_addr *gwaddr) 454 { 455 struct net *net = dev_net(dev); 456 struct route_info *rinfo = (struct route_info *) opt; 457 struct in6_addr prefix_buf, *prefix; 458 unsigned int pref; 459 unsigned long lifetime; 460 struct rt6_info *rt; 461 462 if (len < sizeof(struct route_info)) { 463 return -EINVAL; 464 } 465 466 /* Sanity check for prefix_len and length */ 467 if (rinfo->length > 3) { 468 return -EINVAL; 469 } else if (rinfo->prefix_len > 128) { 470 return -EINVAL; 471 } else if (rinfo->prefix_len > 64) { 472 if (rinfo->length < 2) { 473 return -EINVAL; 474 } 475 } else if (rinfo->prefix_len > 0) { 476 if (rinfo->length < 1) { 477 return -EINVAL; 478 } 479 } 480 481 pref = rinfo->route_pref; 482 if (pref == ICMPV6_ROUTER_PREF_INVALID) 483 pref = ICMPV6_ROUTER_PREF_MEDIUM; 484 485 lifetime = addrconf_timeout_fixup(ntohl(rinfo->lifetime), HZ); 486 487 if (rinfo->length == 3) 488 prefix = (struct in6_addr *)rinfo->prefix; 489 else { 490 /* this function is safe */ 491 ipv6_addr_prefix(&prefix_buf, 492 (struct in6_addr *)rinfo->prefix, 493 rinfo->prefix_len); 494 prefix = &prefix_buf; 495 } 496 497 rt = rt6_get_route_info(net, prefix, rinfo->prefix_len, gwaddr, 498 dev->ifindex); 499 500 if (rt && !lifetime) { 501 ip6_del_rt(rt); 502 rt = NULL; 503 } 504 505 if (!rt && lifetime) 506 rt = rt6_add_route_info(net, prefix, rinfo->prefix_len, gwaddr, dev->ifindex, 507 pref); 508 else if (rt) 509 rt->rt6i_flags = RTF_ROUTEINFO | 510 (rt->rt6i_flags & ~RTF_PREF_MASK) | RTF_PREF(pref); 511 512 if (rt) { 513 if (!addrconf_finite_timeout(lifetime)) { 514 rt->rt6i_flags &= ~RTF_EXPIRES; 515 } else { 516 rt->rt6i_expires = jiffies + HZ * lifetime; 517 rt->rt6i_flags |= RTF_EXPIRES; 518 } 519 dst_release(&rt->u.dst); 520 } 521 return 0; 522 } 523 #endif 524 525 #define BACKTRACK(__net, saddr) \ 526 do { \ 527 if (rt == __net->ipv6.ip6_null_entry) { \ 528 struct fib6_node *pn; \ 529 while (1) { \ 530 if (fn->fn_flags & RTN_TL_ROOT) \ 531 goto out; \ 532 pn = fn->parent; \ 533 if (FIB6_SUBTREE(pn) && FIB6_SUBTREE(pn) != fn) \ 534 fn = fib6_lookup(FIB6_SUBTREE(pn), NULL, saddr); \ 535 else \ 536 fn = pn; \ 537 if (fn->fn_flags & RTN_RTINFO) \ 538 goto restart; \ 539 } \ 540 } \ 541 } while(0) 542 543 static struct rt6_info *ip6_pol_route_lookup(struct net *net, 544 struct fib6_table *table, 545 struct flowi *fl, int flags) 546 { 547 struct fib6_node *fn; 548 struct rt6_info *rt; 549 550 read_lock_bh(&table->tb6_lock); 551 fn = fib6_lookup(&table->tb6_root, &fl->fl6_dst, &fl->fl6_src); 552 restart: 553 rt = fn->leaf; 554 rt = rt6_device_match(net, rt, &fl->fl6_src, fl->oif, flags); 555 BACKTRACK(net, &fl->fl6_src); 556 out: 557 dst_use(&rt->u.dst, jiffies); 558 read_unlock_bh(&table->tb6_lock); 559 return rt; 560 561 } 562 563 struct rt6_info *rt6_lookup(struct net *net, const struct in6_addr *daddr, 564 const struct in6_addr *saddr, int oif, int strict) 565 { 566 struct flowi fl = { 567 .oif = oif, 568 .nl_u = { 569 .ip6_u = { 570 .daddr = *daddr, 571 }, 572 }, 573 }; 574 struct dst_entry *dst; 575 int flags = strict ? RT6_LOOKUP_F_IFACE : 0; 576 577 if (saddr) { 578 memcpy(&fl.fl6_src, saddr, sizeof(*saddr)); 579 flags |= RT6_LOOKUP_F_HAS_SADDR; 580 } 581 582 dst = fib6_rule_lookup(net, &fl, flags, ip6_pol_route_lookup); 583 if (dst->error == 0) 584 return (struct rt6_info *) dst; 585 586 dst_release(dst); 587 588 return NULL; 589 } 590 591 EXPORT_SYMBOL(rt6_lookup); 592 593 /* ip6_ins_rt is called with FREE table->tb6_lock. 594 It takes new route entry, the addition fails by any reason the 595 route is freed. In any case, if caller does not hold it, it may 596 be destroyed. 597 */ 598 599 static int __ip6_ins_rt(struct rt6_info *rt, struct nl_info *info) 600 { 601 int err; 602 struct fib6_table *table; 603 604 table = rt->rt6i_table; 605 write_lock_bh(&table->tb6_lock); 606 err = fib6_add(&table->tb6_root, rt, info); 607 write_unlock_bh(&table->tb6_lock); 608 609 return err; 610 } 611 612 int ip6_ins_rt(struct rt6_info *rt) 613 { 614 struct nl_info info = { 615 .nl_net = dev_net(rt->rt6i_dev), 616 }; 617 return __ip6_ins_rt(rt, &info); 618 } 619 620 static struct rt6_info *rt6_alloc_cow(struct rt6_info *ort, struct in6_addr *daddr, 621 struct in6_addr *saddr) 622 { 623 struct rt6_info *rt; 624 625 /* 626 * Clone the route. 627 */ 628 629 rt = ip6_rt_copy(ort); 630 631 if (rt) { 632 if (!(rt->rt6i_flags&RTF_GATEWAY)) { 633 if (rt->rt6i_dst.plen != 128 && 634 ipv6_addr_equal(&rt->rt6i_dst.addr, daddr)) 635 rt->rt6i_flags |= RTF_ANYCAST; 636 ipv6_addr_copy(&rt->rt6i_gateway, daddr); 637 } 638 639 ipv6_addr_copy(&rt->rt6i_dst.addr, daddr); 640 rt->rt6i_dst.plen = 128; 641 rt->rt6i_flags |= RTF_CACHE; 642 rt->u.dst.flags |= DST_HOST; 643 644 #ifdef CONFIG_IPV6_SUBTREES 645 if (rt->rt6i_src.plen && saddr) { 646 ipv6_addr_copy(&rt->rt6i_src.addr, saddr); 647 rt->rt6i_src.plen = 128; 648 } 649 #endif 650 651 rt->rt6i_nexthop = ndisc_get_neigh(rt->rt6i_dev, &rt->rt6i_gateway); 652 653 } 654 655 return rt; 656 } 657 658 static struct rt6_info *rt6_alloc_clone(struct rt6_info *ort, struct in6_addr *daddr) 659 { 660 struct rt6_info *rt = ip6_rt_copy(ort); 661 if (rt) { 662 ipv6_addr_copy(&rt->rt6i_dst.addr, daddr); 663 rt->rt6i_dst.plen = 128; 664 rt->rt6i_flags |= RTF_CACHE; 665 rt->u.dst.flags |= DST_HOST; 666 rt->rt6i_nexthop = neigh_clone(ort->rt6i_nexthop); 667 } 668 return rt; 669 } 670 671 static struct rt6_info *ip6_pol_route(struct net *net, struct fib6_table *table, int oif, 672 struct flowi *fl, int flags) 673 { 674 struct fib6_node *fn; 675 struct rt6_info *rt, *nrt; 676 int strict = 0; 677 int attempts = 3; 678 int err; 679 int reachable = net->ipv6.devconf_all->forwarding ? 0 : RT6_LOOKUP_F_REACHABLE; 680 681 strict |= flags & RT6_LOOKUP_F_IFACE; 682 683 relookup: 684 read_lock_bh(&table->tb6_lock); 685 686 restart_2: 687 fn = fib6_lookup(&table->tb6_root, &fl->fl6_dst, &fl->fl6_src); 688 689 restart: 690 rt = rt6_select(fn, oif, strict | reachable); 691 692 BACKTRACK(net, &fl->fl6_src); 693 if (rt == net->ipv6.ip6_null_entry || 694 rt->rt6i_flags & RTF_CACHE) 695 goto out; 696 697 dst_hold(&rt->u.dst); 698 read_unlock_bh(&table->tb6_lock); 699 700 if (!rt->rt6i_nexthop && !(rt->rt6i_flags & RTF_NONEXTHOP)) 701 nrt = rt6_alloc_cow(rt, &fl->fl6_dst, &fl->fl6_src); 702 else { 703 #if CLONE_OFFLINK_ROUTE 704 nrt = rt6_alloc_clone(rt, &fl->fl6_dst); 705 #else 706 goto out2; 707 #endif 708 } 709 710 dst_release(&rt->u.dst); 711 rt = nrt ? : net->ipv6.ip6_null_entry; 712 713 dst_hold(&rt->u.dst); 714 if (nrt) { 715 err = ip6_ins_rt(nrt); 716 if (!err) 717 goto out2; 718 } 719 720 if (--attempts <= 0) 721 goto out2; 722 723 /* 724 * Race condition! In the gap, when table->tb6_lock was 725 * released someone could insert this route. Relookup. 726 */ 727 dst_release(&rt->u.dst); 728 goto relookup; 729 730 out: 731 if (reachable) { 732 reachable = 0; 733 goto restart_2; 734 } 735 dst_hold(&rt->u.dst); 736 read_unlock_bh(&table->tb6_lock); 737 out2: 738 rt->u.dst.lastuse = jiffies; 739 rt->u.dst.__use++; 740 741 return rt; 742 } 743 744 static struct rt6_info *ip6_pol_route_input(struct net *net, struct fib6_table *table, 745 struct flowi *fl, int flags) 746 { 747 return ip6_pol_route(net, table, fl->iif, fl, flags); 748 } 749 750 void ip6_route_input(struct sk_buff *skb) 751 { 752 struct ipv6hdr *iph = ipv6_hdr(skb); 753 struct net *net = dev_net(skb->dev); 754 int flags = RT6_LOOKUP_F_HAS_SADDR; 755 struct flowi fl = { 756 .iif = skb->dev->ifindex, 757 .nl_u = { 758 .ip6_u = { 759 .daddr = iph->daddr, 760 .saddr = iph->saddr, 761 .flowlabel = (* (__be32 *) iph)&IPV6_FLOWINFO_MASK, 762 }, 763 }, 764 .mark = skb->mark, 765 .proto = iph->nexthdr, 766 }; 767 768 if (rt6_need_strict(&iph->daddr)) 769 flags |= RT6_LOOKUP_F_IFACE; 770 771 skb->dst = fib6_rule_lookup(net, &fl, flags, ip6_pol_route_input); 772 } 773 774 static struct rt6_info *ip6_pol_route_output(struct net *net, struct fib6_table *table, 775 struct flowi *fl, int flags) 776 { 777 return ip6_pol_route(net, table, fl->oif, fl, flags); 778 } 779 780 struct dst_entry * ip6_route_output(struct net *net, struct sock *sk, 781 struct flowi *fl) 782 { 783 int flags = 0; 784 785 if (rt6_need_strict(&fl->fl6_dst)) 786 flags |= RT6_LOOKUP_F_IFACE; 787 788 if (!ipv6_addr_any(&fl->fl6_src)) 789 flags |= RT6_LOOKUP_F_HAS_SADDR; 790 else if (sk) { 791 unsigned int prefs = inet6_sk(sk)->srcprefs; 792 if (prefs & IPV6_PREFER_SRC_TMP) 793 flags |= RT6_LOOKUP_F_SRCPREF_TMP; 794 if (prefs & IPV6_PREFER_SRC_PUBLIC) 795 flags |= RT6_LOOKUP_F_SRCPREF_PUBLIC; 796 if (prefs & IPV6_PREFER_SRC_COA) 797 flags |= RT6_LOOKUP_F_SRCPREF_COA; 798 } 799 800 return fib6_rule_lookup(net, fl, flags, ip6_pol_route_output); 801 } 802 803 EXPORT_SYMBOL(ip6_route_output); 804 805 int ip6_dst_blackhole(struct sock *sk, struct dst_entry **dstp, struct flowi *fl) 806 { 807 struct rt6_info *ort = (struct rt6_info *) *dstp; 808 struct rt6_info *rt = (struct rt6_info *) 809 dst_alloc(&ip6_dst_blackhole_ops); 810 struct dst_entry *new = NULL; 811 812 if (rt) { 813 new = &rt->u.dst; 814 815 atomic_set(&new->__refcnt, 1); 816 new->__use = 1; 817 new->input = dst_discard; 818 new->output = dst_discard; 819 820 memcpy(new->metrics, ort->u.dst.metrics, RTAX_MAX*sizeof(u32)); 821 new->dev = ort->u.dst.dev; 822 if (new->dev) 823 dev_hold(new->dev); 824 rt->rt6i_idev = ort->rt6i_idev; 825 if (rt->rt6i_idev) 826 in6_dev_hold(rt->rt6i_idev); 827 rt->rt6i_expires = 0; 828 829 ipv6_addr_copy(&rt->rt6i_gateway, &ort->rt6i_gateway); 830 rt->rt6i_flags = ort->rt6i_flags & ~RTF_EXPIRES; 831 rt->rt6i_metric = 0; 832 833 memcpy(&rt->rt6i_dst, &ort->rt6i_dst, sizeof(struct rt6key)); 834 #ifdef CONFIG_IPV6_SUBTREES 835 memcpy(&rt->rt6i_src, &ort->rt6i_src, sizeof(struct rt6key)); 836 #endif 837 838 dst_free(new); 839 } 840 841 dst_release(*dstp); 842 *dstp = new; 843 return (new ? 0 : -ENOMEM); 844 } 845 EXPORT_SYMBOL_GPL(ip6_dst_blackhole); 846 847 /* 848 * Destination cache support functions 849 */ 850 851 static struct dst_entry *ip6_dst_check(struct dst_entry *dst, u32 cookie) 852 { 853 struct rt6_info *rt; 854 855 rt = (struct rt6_info *) dst; 856 857 if (rt && rt->rt6i_node && (rt->rt6i_node->fn_sernum == cookie)) 858 return dst; 859 860 return NULL; 861 } 862 863 static struct dst_entry *ip6_negative_advice(struct dst_entry *dst) 864 { 865 struct rt6_info *rt = (struct rt6_info *) dst; 866 867 if (rt) { 868 if (rt->rt6i_flags & RTF_CACHE) 869 ip6_del_rt(rt); 870 else 871 dst_release(dst); 872 } 873 return NULL; 874 } 875 876 static void ip6_link_failure(struct sk_buff *skb) 877 { 878 struct rt6_info *rt; 879 880 icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_ADDR_UNREACH, 0, skb->dev); 881 882 rt = (struct rt6_info *) skb->dst; 883 if (rt) { 884 if (rt->rt6i_flags&RTF_CACHE) { 885 dst_set_expires(&rt->u.dst, 0); 886 rt->rt6i_flags |= RTF_EXPIRES; 887 } else if (rt->rt6i_node && (rt->rt6i_flags & RTF_DEFAULT)) 888 rt->rt6i_node->fn_sernum = -1; 889 } 890 } 891 892 static void ip6_rt_update_pmtu(struct dst_entry *dst, u32 mtu) 893 { 894 struct rt6_info *rt6 = (struct rt6_info*)dst; 895 896 if (mtu < dst_mtu(dst) && rt6->rt6i_dst.plen == 128) { 897 rt6->rt6i_flags |= RTF_MODIFIED; 898 if (mtu < IPV6_MIN_MTU) { 899 mtu = IPV6_MIN_MTU; 900 dst->metrics[RTAX_FEATURES-1] |= RTAX_FEATURE_ALLFRAG; 901 } 902 dst->metrics[RTAX_MTU-1] = mtu; 903 call_netevent_notifiers(NETEVENT_PMTU_UPDATE, dst); 904 } 905 } 906 907 static int ipv6_get_mtu(struct net_device *dev); 908 909 static inline unsigned int ipv6_advmss(struct net *net, unsigned int mtu) 910 { 911 mtu -= sizeof(struct ipv6hdr) + sizeof(struct tcphdr); 912 913 if (mtu < net->ipv6.sysctl.ip6_rt_min_advmss) 914 mtu = net->ipv6.sysctl.ip6_rt_min_advmss; 915 916 /* 917 * Maximal non-jumbo IPv6 payload is IPV6_MAXPLEN and 918 * corresponding MSS is IPV6_MAXPLEN - tcp_header_size. 919 * IPV6_MAXPLEN is also valid and means: "any MSS, 920 * rely only on pmtu discovery" 921 */ 922 if (mtu > IPV6_MAXPLEN - sizeof(struct tcphdr)) 923 mtu = IPV6_MAXPLEN; 924 return mtu; 925 } 926 927 static struct dst_entry *icmp6_dst_gc_list; 928 static DEFINE_SPINLOCK(icmp6_dst_lock); 929 930 struct dst_entry *icmp6_dst_alloc(struct net_device *dev, 931 struct neighbour *neigh, 932 const struct in6_addr *addr) 933 { 934 struct rt6_info *rt; 935 struct inet6_dev *idev = in6_dev_get(dev); 936 struct net *net = dev_net(dev); 937 938 if (unlikely(idev == NULL)) 939 return NULL; 940 941 rt = ip6_dst_alloc(net->ipv6.ip6_dst_ops); 942 if (unlikely(rt == NULL)) { 943 in6_dev_put(idev); 944 goto out; 945 } 946 947 dev_hold(dev); 948 if (neigh) 949 neigh_hold(neigh); 950 else 951 neigh = ndisc_get_neigh(dev, addr); 952 953 rt->rt6i_dev = dev; 954 rt->rt6i_idev = idev; 955 rt->rt6i_nexthop = neigh; 956 atomic_set(&rt->u.dst.__refcnt, 1); 957 rt->u.dst.metrics[RTAX_HOPLIMIT-1] = 255; 958 rt->u.dst.metrics[RTAX_MTU-1] = ipv6_get_mtu(rt->rt6i_dev); 959 rt->u.dst.metrics[RTAX_ADVMSS-1] = ipv6_advmss(net, dst_mtu(&rt->u.dst)); 960 rt->u.dst.output = ip6_output; 961 962 #if 0 /* there's no chance to use these for ndisc */ 963 rt->u.dst.flags = ipv6_addr_type(addr) & IPV6_ADDR_UNICAST 964 ? DST_HOST 965 : 0; 966 ipv6_addr_copy(&rt->rt6i_dst.addr, addr); 967 rt->rt6i_dst.plen = 128; 968 #endif 969 970 spin_lock_bh(&icmp6_dst_lock); 971 rt->u.dst.next = icmp6_dst_gc_list; 972 icmp6_dst_gc_list = &rt->u.dst; 973 spin_unlock_bh(&icmp6_dst_lock); 974 975 fib6_force_start_gc(net); 976 977 out: 978 return &rt->u.dst; 979 } 980 981 int icmp6_dst_gc(void) 982 { 983 struct dst_entry *dst, *next, **pprev; 984 int more = 0; 985 986 next = NULL; 987 988 spin_lock_bh(&icmp6_dst_lock); 989 pprev = &icmp6_dst_gc_list; 990 991 while ((dst = *pprev) != NULL) { 992 if (!atomic_read(&dst->__refcnt)) { 993 *pprev = dst->next; 994 dst_free(dst); 995 } else { 996 pprev = &dst->next; 997 ++more; 998 } 999 } 1000 1001 spin_unlock_bh(&icmp6_dst_lock); 1002 1003 return more; 1004 } 1005 1006 static int ip6_dst_gc(struct dst_ops *ops) 1007 { 1008 unsigned long now = jiffies; 1009 struct net *net = ops->dst_net; 1010 int rt_min_interval = net->ipv6.sysctl.ip6_rt_gc_min_interval; 1011 int rt_max_size = net->ipv6.sysctl.ip6_rt_max_size; 1012 int rt_elasticity = net->ipv6.sysctl.ip6_rt_gc_elasticity; 1013 int rt_gc_timeout = net->ipv6.sysctl.ip6_rt_gc_timeout; 1014 unsigned long rt_last_gc = net->ipv6.ip6_rt_last_gc; 1015 1016 if (time_after(rt_last_gc + rt_min_interval, now) && 1017 atomic_read(&ops->entries) <= rt_max_size) 1018 goto out; 1019 1020 net->ipv6.ip6_rt_gc_expire++; 1021 fib6_run_gc(net->ipv6.ip6_rt_gc_expire, net); 1022 net->ipv6.ip6_rt_last_gc = now; 1023 if (atomic_read(&ops->entries) < ops->gc_thresh) 1024 net->ipv6.ip6_rt_gc_expire = rt_gc_timeout>>1; 1025 out: 1026 net->ipv6.ip6_rt_gc_expire -= net->ipv6.ip6_rt_gc_expire>>rt_elasticity; 1027 return (atomic_read(&ops->entries) > rt_max_size); 1028 } 1029 1030 /* Clean host part of a prefix. Not necessary in radix tree, 1031 but results in cleaner routing tables. 1032 1033 Remove it only when all the things will work! 1034 */ 1035 1036 static int ipv6_get_mtu(struct net_device *dev) 1037 { 1038 int mtu = IPV6_MIN_MTU; 1039 struct inet6_dev *idev; 1040 1041 idev = in6_dev_get(dev); 1042 if (idev) { 1043 mtu = idev->cnf.mtu6; 1044 in6_dev_put(idev); 1045 } 1046 return mtu; 1047 } 1048 1049 int ip6_dst_hoplimit(struct dst_entry *dst) 1050 { 1051 int hoplimit = dst_metric(dst, RTAX_HOPLIMIT); 1052 if (hoplimit < 0) { 1053 struct net_device *dev = dst->dev; 1054 struct inet6_dev *idev = in6_dev_get(dev); 1055 if (idev) { 1056 hoplimit = idev->cnf.hop_limit; 1057 in6_dev_put(idev); 1058 } else 1059 hoplimit = dev_net(dev)->ipv6.devconf_all->hop_limit; 1060 } 1061 return hoplimit; 1062 } 1063 1064 /* 1065 * 1066 */ 1067 1068 int ip6_route_add(struct fib6_config *cfg) 1069 { 1070 int err; 1071 struct net *net = cfg->fc_nlinfo.nl_net; 1072 struct rt6_info *rt = NULL; 1073 struct net_device *dev = NULL; 1074 struct inet6_dev *idev = NULL; 1075 struct fib6_table *table; 1076 int addr_type; 1077 1078 if (cfg->fc_dst_len > 128 || cfg->fc_src_len > 128) 1079 return -EINVAL; 1080 #ifndef CONFIG_IPV6_SUBTREES 1081 if (cfg->fc_src_len) 1082 return -EINVAL; 1083 #endif 1084 if (cfg->fc_ifindex) { 1085 err = -ENODEV; 1086 dev = dev_get_by_index(net, cfg->fc_ifindex); 1087 if (!dev) 1088 goto out; 1089 idev = in6_dev_get(dev); 1090 if (!idev) 1091 goto out; 1092 } 1093 1094 if (cfg->fc_metric == 0) 1095 cfg->fc_metric = IP6_RT_PRIO_USER; 1096 1097 table = fib6_new_table(net, cfg->fc_table); 1098 if (table == NULL) { 1099 err = -ENOBUFS; 1100 goto out; 1101 } 1102 1103 rt = ip6_dst_alloc(net->ipv6.ip6_dst_ops); 1104 1105 if (rt == NULL) { 1106 err = -ENOMEM; 1107 goto out; 1108 } 1109 1110 rt->u.dst.obsolete = -1; 1111 rt->rt6i_expires = (cfg->fc_flags & RTF_EXPIRES) ? 1112 jiffies + clock_t_to_jiffies(cfg->fc_expires) : 1113 0; 1114 1115 if (cfg->fc_protocol == RTPROT_UNSPEC) 1116 cfg->fc_protocol = RTPROT_BOOT; 1117 rt->rt6i_protocol = cfg->fc_protocol; 1118 1119 addr_type = ipv6_addr_type(&cfg->fc_dst); 1120 1121 if (addr_type & IPV6_ADDR_MULTICAST) 1122 rt->u.dst.input = ip6_mc_input; 1123 else 1124 rt->u.dst.input = ip6_forward; 1125 1126 rt->u.dst.output = ip6_output; 1127 1128 ipv6_addr_prefix(&rt->rt6i_dst.addr, &cfg->fc_dst, cfg->fc_dst_len); 1129 rt->rt6i_dst.plen = cfg->fc_dst_len; 1130 if (rt->rt6i_dst.plen == 128) 1131 rt->u.dst.flags = DST_HOST; 1132 1133 #ifdef CONFIG_IPV6_SUBTREES 1134 ipv6_addr_prefix(&rt->rt6i_src.addr, &cfg->fc_src, cfg->fc_src_len); 1135 rt->rt6i_src.plen = cfg->fc_src_len; 1136 #endif 1137 1138 rt->rt6i_metric = cfg->fc_metric; 1139 1140 /* We cannot add true routes via loopback here, 1141 they would result in kernel looping; promote them to reject routes 1142 */ 1143 if ((cfg->fc_flags & RTF_REJECT) || 1144 (dev && (dev->flags&IFF_LOOPBACK) && !(addr_type&IPV6_ADDR_LOOPBACK))) { 1145 /* hold loopback dev/idev if we haven't done so. */ 1146 if (dev != net->loopback_dev) { 1147 if (dev) { 1148 dev_put(dev); 1149 in6_dev_put(idev); 1150 } 1151 dev = net->loopback_dev; 1152 dev_hold(dev); 1153 idev = in6_dev_get(dev); 1154 if (!idev) { 1155 err = -ENODEV; 1156 goto out; 1157 } 1158 } 1159 rt->u.dst.output = ip6_pkt_discard_out; 1160 rt->u.dst.input = ip6_pkt_discard; 1161 rt->u.dst.error = -ENETUNREACH; 1162 rt->rt6i_flags = RTF_REJECT|RTF_NONEXTHOP; 1163 goto install_route; 1164 } 1165 1166 if (cfg->fc_flags & RTF_GATEWAY) { 1167 struct in6_addr *gw_addr; 1168 int gwa_type; 1169 1170 gw_addr = &cfg->fc_gateway; 1171 ipv6_addr_copy(&rt->rt6i_gateway, gw_addr); 1172 gwa_type = ipv6_addr_type(gw_addr); 1173 1174 if (gwa_type != (IPV6_ADDR_LINKLOCAL|IPV6_ADDR_UNICAST)) { 1175 struct rt6_info *grt; 1176 1177 /* IPv6 strictly inhibits using not link-local 1178 addresses as nexthop address. 1179 Otherwise, router will not able to send redirects. 1180 It is very good, but in some (rare!) circumstances 1181 (SIT, PtP, NBMA NOARP links) it is handy to allow 1182 some exceptions. --ANK 1183 */ 1184 err = -EINVAL; 1185 if (!(gwa_type&IPV6_ADDR_UNICAST)) 1186 goto out; 1187 1188 grt = rt6_lookup(net, gw_addr, NULL, cfg->fc_ifindex, 1); 1189 1190 err = -EHOSTUNREACH; 1191 if (grt == NULL) 1192 goto out; 1193 if (dev) { 1194 if (dev != grt->rt6i_dev) { 1195 dst_release(&grt->u.dst); 1196 goto out; 1197 } 1198 } else { 1199 dev = grt->rt6i_dev; 1200 idev = grt->rt6i_idev; 1201 dev_hold(dev); 1202 in6_dev_hold(grt->rt6i_idev); 1203 } 1204 if (!(grt->rt6i_flags&RTF_GATEWAY)) 1205 err = 0; 1206 dst_release(&grt->u.dst); 1207 1208 if (err) 1209 goto out; 1210 } 1211 err = -EINVAL; 1212 if (dev == NULL || (dev->flags&IFF_LOOPBACK)) 1213 goto out; 1214 } 1215 1216 err = -ENODEV; 1217 if (dev == NULL) 1218 goto out; 1219 1220 if (cfg->fc_flags & (RTF_GATEWAY | RTF_NONEXTHOP)) { 1221 rt->rt6i_nexthop = __neigh_lookup_errno(&nd_tbl, &rt->rt6i_gateway, dev); 1222 if (IS_ERR(rt->rt6i_nexthop)) { 1223 err = PTR_ERR(rt->rt6i_nexthop); 1224 rt->rt6i_nexthop = NULL; 1225 goto out; 1226 } 1227 } 1228 1229 rt->rt6i_flags = cfg->fc_flags; 1230 1231 install_route: 1232 if (cfg->fc_mx) { 1233 struct nlattr *nla; 1234 int remaining; 1235 1236 nla_for_each_attr(nla, cfg->fc_mx, cfg->fc_mx_len, remaining) { 1237 int type = nla_type(nla); 1238 1239 if (type) { 1240 if (type > RTAX_MAX) { 1241 err = -EINVAL; 1242 goto out; 1243 } 1244 1245 rt->u.dst.metrics[type - 1] = nla_get_u32(nla); 1246 } 1247 } 1248 } 1249 1250 if (dst_metric(&rt->u.dst, RTAX_HOPLIMIT) == 0) 1251 rt->u.dst.metrics[RTAX_HOPLIMIT-1] = -1; 1252 if (!dst_metric(&rt->u.dst, RTAX_MTU)) 1253 rt->u.dst.metrics[RTAX_MTU-1] = ipv6_get_mtu(dev); 1254 if (!dst_metric(&rt->u.dst, RTAX_ADVMSS)) 1255 rt->u.dst.metrics[RTAX_ADVMSS-1] = ipv6_advmss(net, dst_mtu(&rt->u.dst)); 1256 rt->u.dst.dev = dev; 1257 rt->rt6i_idev = idev; 1258 rt->rt6i_table = table; 1259 1260 cfg->fc_nlinfo.nl_net = dev_net(dev); 1261 1262 return __ip6_ins_rt(rt, &cfg->fc_nlinfo); 1263 1264 out: 1265 if (dev) 1266 dev_put(dev); 1267 if (idev) 1268 in6_dev_put(idev); 1269 if (rt) 1270 dst_free(&rt->u.dst); 1271 return err; 1272 } 1273 1274 static int __ip6_del_rt(struct rt6_info *rt, struct nl_info *info) 1275 { 1276 int err; 1277 struct fib6_table *table; 1278 struct net *net = dev_net(rt->rt6i_dev); 1279 1280 if (rt == net->ipv6.ip6_null_entry) 1281 return -ENOENT; 1282 1283 table = rt->rt6i_table; 1284 write_lock_bh(&table->tb6_lock); 1285 1286 err = fib6_del(rt, info); 1287 dst_release(&rt->u.dst); 1288 1289 write_unlock_bh(&table->tb6_lock); 1290 1291 return err; 1292 } 1293 1294 int ip6_del_rt(struct rt6_info *rt) 1295 { 1296 struct nl_info info = { 1297 .nl_net = dev_net(rt->rt6i_dev), 1298 }; 1299 return __ip6_del_rt(rt, &info); 1300 } 1301 1302 static int ip6_route_del(struct fib6_config *cfg) 1303 { 1304 struct fib6_table *table; 1305 struct fib6_node *fn; 1306 struct rt6_info *rt; 1307 int err = -ESRCH; 1308 1309 table = fib6_get_table(cfg->fc_nlinfo.nl_net, cfg->fc_table); 1310 if (table == NULL) 1311 return err; 1312 1313 read_lock_bh(&table->tb6_lock); 1314 1315 fn = fib6_locate(&table->tb6_root, 1316 &cfg->fc_dst, cfg->fc_dst_len, 1317 &cfg->fc_src, cfg->fc_src_len); 1318 1319 if (fn) { 1320 for (rt = fn->leaf; rt; rt = rt->u.dst.rt6_next) { 1321 if (cfg->fc_ifindex && 1322 (rt->rt6i_dev == NULL || 1323 rt->rt6i_dev->ifindex != cfg->fc_ifindex)) 1324 continue; 1325 if (cfg->fc_flags & RTF_GATEWAY && 1326 !ipv6_addr_equal(&cfg->fc_gateway, &rt->rt6i_gateway)) 1327 continue; 1328 if (cfg->fc_metric && cfg->fc_metric != rt->rt6i_metric) 1329 continue; 1330 dst_hold(&rt->u.dst); 1331 read_unlock_bh(&table->tb6_lock); 1332 1333 return __ip6_del_rt(rt, &cfg->fc_nlinfo); 1334 } 1335 } 1336 read_unlock_bh(&table->tb6_lock); 1337 1338 return err; 1339 } 1340 1341 /* 1342 * Handle redirects 1343 */ 1344 struct ip6rd_flowi { 1345 struct flowi fl; 1346 struct in6_addr gateway; 1347 }; 1348 1349 static struct rt6_info *__ip6_route_redirect(struct net *net, 1350 struct fib6_table *table, 1351 struct flowi *fl, 1352 int flags) 1353 { 1354 struct ip6rd_flowi *rdfl = (struct ip6rd_flowi *)fl; 1355 struct rt6_info *rt; 1356 struct fib6_node *fn; 1357 1358 /* 1359 * Get the "current" route for this destination and 1360 * check if the redirect has come from approriate router. 1361 * 1362 * RFC 2461 specifies that redirects should only be 1363 * accepted if they come from the nexthop to the target. 1364 * Due to the way the routes are chosen, this notion 1365 * is a bit fuzzy and one might need to check all possible 1366 * routes. 1367 */ 1368 1369 read_lock_bh(&table->tb6_lock); 1370 fn = fib6_lookup(&table->tb6_root, &fl->fl6_dst, &fl->fl6_src); 1371 restart: 1372 for (rt = fn->leaf; rt; rt = rt->u.dst.rt6_next) { 1373 /* 1374 * Current route is on-link; redirect is always invalid. 1375 * 1376 * Seems, previous statement is not true. It could 1377 * be node, which looks for us as on-link (f.e. proxy ndisc) 1378 * But then router serving it might decide, that we should 1379 * know truth 8)8) --ANK (980726). 1380 */ 1381 if (rt6_check_expired(rt)) 1382 continue; 1383 if (!(rt->rt6i_flags & RTF_GATEWAY)) 1384 continue; 1385 if (fl->oif != rt->rt6i_dev->ifindex) 1386 continue; 1387 if (!ipv6_addr_equal(&rdfl->gateway, &rt->rt6i_gateway)) 1388 continue; 1389 break; 1390 } 1391 1392 if (!rt) 1393 rt = net->ipv6.ip6_null_entry; 1394 BACKTRACK(net, &fl->fl6_src); 1395 out: 1396 dst_hold(&rt->u.dst); 1397 1398 read_unlock_bh(&table->tb6_lock); 1399 1400 return rt; 1401 }; 1402 1403 static struct rt6_info *ip6_route_redirect(struct in6_addr *dest, 1404 struct in6_addr *src, 1405 struct in6_addr *gateway, 1406 struct net_device *dev) 1407 { 1408 int flags = RT6_LOOKUP_F_HAS_SADDR; 1409 struct net *net = dev_net(dev); 1410 struct ip6rd_flowi rdfl = { 1411 .fl = { 1412 .oif = dev->ifindex, 1413 .nl_u = { 1414 .ip6_u = { 1415 .daddr = *dest, 1416 .saddr = *src, 1417 }, 1418 }, 1419 }, 1420 .gateway = *gateway, 1421 }; 1422 1423 if (rt6_need_strict(dest)) 1424 flags |= RT6_LOOKUP_F_IFACE; 1425 1426 return (struct rt6_info *)fib6_rule_lookup(net, (struct flowi *)&rdfl, 1427 flags, __ip6_route_redirect); 1428 } 1429 1430 void rt6_redirect(struct in6_addr *dest, struct in6_addr *src, 1431 struct in6_addr *saddr, 1432 struct neighbour *neigh, u8 *lladdr, int on_link) 1433 { 1434 struct rt6_info *rt, *nrt = NULL; 1435 struct netevent_redirect netevent; 1436 struct net *net = dev_net(neigh->dev); 1437 1438 rt = ip6_route_redirect(dest, src, saddr, neigh->dev); 1439 1440 if (rt == net->ipv6.ip6_null_entry) { 1441 if (net_ratelimit()) 1442 printk(KERN_DEBUG "rt6_redirect: source isn't a valid nexthop " 1443 "for redirect target\n"); 1444 goto out; 1445 } 1446 1447 /* 1448 * We have finally decided to accept it. 1449 */ 1450 1451 neigh_update(neigh, lladdr, NUD_STALE, 1452 NEIGH_UPDATE_F_WEAK_OVERRIDE| 1453 NEIGH_UPDATE_F_OVERRIDE| 1454 (on_link ? 0 : (NEIGH_UPDATE_F_OVERRIDE_ISROUTER| 1455 NEIGH_UPDATE_F_ISROUTER)) 1456 ); 1457 1458 /* 1459 * Redirect received -> path was valid. 1460 * Look, redirects are sent only in response to data packets, 1461 * so that this nexthop apparently is reachable. --ANK 1462 */ 1463 dst_confirm(&rt->u.dst); 1464 1465 /* Duplicate redirect: silently ignore. */ 1466 if (neigh == rt->u.dst.neighbour) 1467 goto out; 1468 1469 nrt = ip6_rt_copy(rt); 1470 if (nrt == NULL) 1471 goto out; 1472 1473 nrt->rt6i_flags = RTF_GATEWAY|RTF_UP|RTF_DYNAMIC|RTF_CACHE; 1474 if (on_link) 1475 nrt->rt6i_flags &= ~RTF_GATEWAY; 1476 1477 ipv6_addr_copy(&nrt->rt6i_dst.addr, dest); 1478 nrt->rt6i_dst.plen = 128; 1479 nrt->u.dst.flags |= DST_HOST; 1480 1481 ipv6_addr_copy(&nrt->rt6i_gateway, (struct in6_addr*)neigh->primary_key); 1482 nrt->rt6i_nexthop = neigh_clone(neigh); 1483 /* Reset pmtu, it may be better */ 1484 nrt->u.dst.metrics[RTAX_MTU-1] = ipv6_get_mtu(neigh->dev); 1485 nrt->u.dst.metrics[RTAX_ADVMSS-1] = ipv6_advmss(dev_net(neigh->dev), 1486 dst_mtu(&nrt->u.dst)); 1487 1488 if (ip6_ins_rt(nrt)) 1489 goto out; 1490 1491 netevent.old = &rt->u.dst; 1492 netevent.new = &nrt->u.dst; 1493 call_netevent_notifiers(NETEVENT_REDIRECT, &netevent); 1494 1495 if (rt->rt6i_flags&RTF_CACHE) { 1496 ip6_del_rt(rt); 1497 return; 1498 } 1499 1500 out: 1501 dst_release(&rt->u.dst); 1502 return; 1503 } 1504 1505 /* 1506 * Handle ICMP "packet too big" messages 1507 * i.e. Path MTU discovery 1508 */ 1509 1510 void rt6_pmtu_discovery(struct in6_addr *daddr, struct in6_addr *saddr, 1511 struct net_device *dev, u32 pmtu) 1512 { 1513 struct rt6_info *rt, *nrt; 1514 struct net *net = dev_net(dev); 1515 int allfrag = 0; 1516 1517 rt = rt6_lookup(net, daddr, saddr, dev->ifindex, 0); 1518 if (rt == NULL) 1519 return; 1520 1521 if (pmtu >= dst_mtu(&rt->u.dst)) 1522 goto out; 1523 1524 if (pmtu < IPV6_MIN_MTU) { 1525 /* 1526 * According to RFC2460, PMTU is set to the IPv6 Minimum Link 1527 * MTU (1280) and a fragment header should always be included 1528 * after a node receiving Too Big message reporting PMTU is 1529 * less than the IPv6 Minimum Link MTU. 1530 */ 1531 pmtu = IPV6_MIN_MTU; 1532 allfrag = 1; 1533 } 1534 1535 /* New mtu received -> path was valid. 1536 They are sent only in response to data packets, 1537 so that this nexthop apparently is reachable. --ANK 1538 */ 1539 dst_confirm(&rt->u.dst); 1540 1541 /* Host route. If it is static, it would be better 1542 not to override it, but add new one, so that 1543 when cache entry will expire old pmtu 1544 would return automatically. 1545 */ 1546 if (rt->rt6i_flags & RTF_CACHE) { 1547 rt->u.dst.metrics[RTAX_MTU-1] = pmtu; 1548 if (allfrag) 1549 rt->u.dst.metrics[RTAX_FEATURES-1] |= RTAX_FEATURE_ALLFRAG; 1550 dst_set_expires(&rt->u.dst, net->ipv6.sysctl.ip6_rt_mtu_expires); 1551 rt->rt6i_flags |= RTF_MODIFIED|RTF_EXPIRES; 1552 goto out; 1553 } 1554 1555 /* Network route. 1556 Two cases are possible: 1557 1. It is connected route. Action: COW 1558 2. It is gatewayed route or NONEXTHOP route. Action: clone it. 1559 */ 1560 if (!rt->rt6i_nexthop && !(rt->rt6i_flags & RTF_NONEXTHOP)) 1561 nrt = rt6_alloc_cow(rt, daddr, saddr); 1562 else 1563 nrt = rt6_alloc_clone(rt, daddr); 1564 1565 if (nrt) { 1566 nrt->u.dst.metrics[RTAX_MTU-1] = pmtu; 1567 if (allfrag) 1568 nrt->u.dst.metrics[RTAX_FEATURES-1] |= RTAX_FEATURE_ALLFRAG; 1569 1570 /* According to RFC 1981, detecting PMTU increase shouldn't be 1571 * happened within 5 mins, the recommended timer is 10 mins. 1572 * Here this route expiration time is set to ip6_rt_mtu_expires 1573 * which is 10 mins. After 10 mins the decreased pmtu is expired 1574 * and detecting PMTU increase will be automatically happened. 1575 */ 1576 dst_set_expires(&nrt->u.dst, net->ipv6.sysctl.ip6_rt_mtu_expires); 1577 nrt->rt6i_flags |= RTF_DYNAMIC|RTF_EXPIRES; 1578 1579 ip6_ins_rt(nrt); 1580 } 1581 out: 1582 dst_release(&rt->u.dst); 1583 } 1584 1585 /* 1586 * Misc support functions 1587 */ 1588 1589 static struct rt6_info * ip6_rt_copy(struct rt6_info *ort) 1590 { 1591 struct net *net = dev_net(ort->rt6i_dev); 1592 struct rt6_info *rt = ip6_dst_alloc(net->ipv6.ip6_dst_ops); 1593 1594 if (rt) { 1595 rt->u.dst.input = ort->u.dst.input; 1596 rt->u.dst.output = ort->u.dst.output; 1597 1598 memcpy(rt->u.dst.metrics, ort->u.dst.metrics, RTAX_MAX*sizeof(u32)); 1599 rt->u.dst.error = ort->u.dst.error; 1600 rt->u.dst.dev = ort->u.dst.dev; 1601 if (rt->u.dst.dev) 1602 dev_hold(rt->u.dst.dev); 1603 rt->rt6i_idev = ort->rt6i_idev; 1604 if (rt->rt6i_idev) 1605 in6_dev_hold(rt->rt6i_idev); 1606 rt->u.dst.lastuse = jiffies; 1607 rt->rt6i_expires = 0; 1608 1609 ipv6_addr_copy(&rt->rt6i_gateway, &ort->rt6i_gateway); 1610 rt->rt6i_flags = ort->rt6i_flags & ~RTF_EXPIRES; 1611 rt->rt6i_metric = 0; 1612 1613 memcpy(&rt->rt6i_dst, &ort->rt6i_dst, sizeof(struct rt6key)); 1614 #ifdef CONFIG_IPV6_SUBTREES 1615 memcpy(&rt->rt6i_src, &ort->rt6i_src, sizeof(struct rt6key)); 1616 #endif 1617 rt->rt6i_table = ort->rt6i_table; 1618 } 1619 return rt; 1620 } 1621 1622 #ifdef CONFIG_IPV6_ROUTE_INFO 1623 static struct rt6_info *rt6_get_route_info(struct net *net, 1624 struct in6_addr *prefix, int prefixlen, 1625 struct in6_addr *gwaddr, int ifindex) 1626 { 1627 struct fib6_node *fn; 1628 struct rt6_info *rt = NULL; 1629 struct fib6_table *table; 1630 1631 table = fib6_get_table(net, RT6_TABLE_INFO); 1632 if (table == NULL) 1633 return NULL; 1634 1635 write_lock_bh(&table->tb6_lock); 1636 fn = fib6_locate(&table->tb6_root, prefix ,prefixlen, NULL, 0); 1637 if (!fn) 1638 goto out; 1639 1640 for (rt = fn->leaf; rt; rt = rt->u.dst.rt6_next) { 1641 if (rt->rt6i_dev->ifindex != ifindex) 1642 continue; 1643 if ((rt->rt6i_flags & (RTF_ROUTEINFO|RTF_GATEWAY)) != (RTF_ROUTEINFO|RTF_GATEWAY)) 1644 continue; 1645 if (!ipv6_addr_equal(&rt->rt6i_gateway, gwaddr)) 1646 continue; 1647 dst_hold(&rt->u.dst); 1648 break; 1649 } 1650 out: 1651 write_unlock_bh(&table->tb6_lock); 1652 return rt; 1653 } 1654 1655 static struct rt6_info *rt6_add_route_info(struct net *net, 1656 struct in6_addr *prefix, int prefixlen, 1657 struct in6_addr *gwaddr, int ifindex, 1658 unsigned pref) 1659 { 1660 struct fib6_config cfg = { 1661 .fc_table = RT6_TABLE_INFO, 1662 .fc_metric = IP6_RT_PRIO_USER, 1663 .fc_ifindex = ifindex, 1664 .fc_dst_len = prefixlen, 1665 .fc_flags = RTF_GATEWAY | RTF_ADDRCONF | RTF_ROUTEINFO | 1666 RTF_UP | RTF_PREF(pref), 1667 .fc_nlinfo.pid = 0, 1668 .fc_nlinfo.nlh = NULL, 1669 .fc_nlinfo.nl_net = net, 1670 }; 1671 1672 ipv6_addr_copy(&cfg.fc_dst, prefix); 1673 ipv6_addr_copy(&cfg.fc_gateway, gwaddr); 1674 1675 /* We should treat it as a default route if prefix length is 0. */ 1676 if (!prefixlen) 1677 cfg.fc_flags |= RTF_DEFAULT; 1678 1679 ip6_route_add(&cfg); 1680 1681 return rt6_get_route_info(net, prefix, prefixlen, gwaddr, ifindex); 1682 } 1683 #endif 1684 1685 struct rt6_info *rt6_get_dflt_router(struct in6_addr *addr, struct net_device *dev) 1686 { 1687 struct rt6_info *rt; 1688 struct fib6_table *table; 1689 1690 table = fib6_get_table(dev_net(dev), RT6_TABLE_DFLT); 1691 if (table == NULL) 1692 return NULL; 1693 1694 write_lock_bh(&table->tb6_lock); 1695 for (rt = table->tb6_root.leaf; rt; rt=rt->u.dst.rt6_next) { 1696 if (dev == rt->rt6i_dev && 1697 ((rt->rt6i_flags & (RTF_ADDRCONF | RTF_DEFAULT)) == (RTF_ADDRCONF | RTF_DEFAULT)) && 1698 ipv6_addr_equal(&rt->rt6i_gateway, addr)) 1699 break; 1700 } 1701 if (rt) 1702 dst_hold(&rt->u.dst); 1703 write_unlock_bh(&table->tb6_lock); 1704 return rt; 1705 } 1706 1707 struct rt6_info *rt6_add_dflt_router(struct in6_addr *gwaddr, 1708 struct net_device *dev, 1709 unsigned int pref) 1710 { 1711 struct fib6_config cfg = { 1712 .fc_table = RT6_TABLE_DFLT, 1713 .fc_metric = IP6_RT_PRIO_USER, 1714 .fc_ifindex = dev->ifindex, 1715 .fc_flags = RTF_GATEWAY | RTF_ADDRCONF | RTF_DEFAULT | 1716 RTF_UP | RTF_EXPIRES | RTF_PREF(pref), 1717 .fc_nlinfo.pid = 0, 1718 .fc_nlinfo.nlh = NULL, 1719 .fc_nlinfo.nl_net = dev_net(dev), 1720 }; 1721 1722 ipv6_addr_copy(&cfg.fc_gateway, gwaddr); 1723 1724 ip6_route_add(&cfg); 1725 1726 return rt6_get_dflt_router(gwaddr, dev); 1727 } 1728 1729 void rt6_purge_dflt_routers(struct net *net) 1730 { 1731 struct rt6_info *rt; 1732 struct fib6_table *table; 1733 1734 /* NOTE: Keep consistent with rt6_get_dflt_router */ 1735 table = fib6_get_table(net, RT6_TABLE_DFLT); 1736 if (table == NULL) 1737 return; 1738 1739 restart: 1740 read_lock_bh(&table->tb6_lock); 1741 for (rt = table->tb6_root.leaf; rt; rt = rt->u.dst.rt6_next) { 1742 if (rt->rt6i_flags & (RTF_DEFAULT | RTF_ADDRCONF)) { 1743 dst_hold(&rt->u.dst); 1744 read_unlock_bh(&table->tb6_lock); 1745 ip6_del_rt(rt); 1746 goto restart; 1747 } 1748 } 1749 read_unlock_bh(&table->tb6_lock); 1750 } 1751 1752 static void rtmsg_to_fib6_config(struct net *net, 1753 struct in6_rtmsg *rtmsg, 1754 struct fib6_config *cfg) 1755 { 1756 memset(cfg, 0, sizeof(*cfg)); 1757 1758 cfg->fc_table = RT6_TABLE_MAIN; 1759 cfg->fc_ifindex = rtmsg->rtmsg_ifindex; 1760 cfg->fc_metric = rtmsg->rtmsg_metric; 1761 cfg->fc_expires = rtmsg->rtmsg_info; 1762 cfg->fc_dst_len = rtmsg->rtmsg_dst_len; 1763 cfg->fc_src_len = rtmsg->rtmsg_src_len; 1764 cfg->fc_flags = rtmsg->rtmsg_flags; 1765 1766 cfg->fc_nlinfo.nl_net = net; 1767 1768 ipv6_addr_copy(&cfg->fc_dst, &rtmsg->rtmsg_dst); 1769 ipv6_addr_copy(&cfg->fc_src, &rtmsg->rtmsg_src); 1770 ipv6_addr_copy(&cfg->fc_gateway, &rtmsg->rtmsg_gateway); 1771 } 1772 1773 int ipv6_route_ioctl(struct net *net, unsigned int cmd, void __user *arg) 1774 { 1775 struct fib6_config cfg; 1776 struct in6_rtmsg rtmsg; 1777 int err; 1778 1779 switch(cmd) { 1780 case SIOCADDRT: /* Add a route */ 1781 case SIOCDELRT: /* Delete a route */ 1782 if (!capable(CAP_NET_ADMIN)) 1783 return -EPERM; 1784 err = copy_from_user(&rtmsg, arg, 1785 sizeof(struct in6_rtmsg)); 1786 if (err) 1787 return -EFAULT; 1788 1789 rtmsg_to_fib6_config(net, &rtmsg, &cfg); 1790 1791 rtnl_lock(); 1792 switch (cmd) { 1793 case SIOCADDRT: 1794 err = ip6_route_add(&cfg); 1795 break; 1796 case SIOCDELRT: 1797 err = ip6_route_del(&cfg); 1798 break; 1799 default: 1800 err = -EINVAL; 1801 } 1802 rtnl_unlock(); 1803 1804 return err; 1805 } 1806 1807 return -EINVAL; 1808 } 1809 1810 /* 1811 * Drop the packet on the floor 1812 */ 1813 1814 static int ip6_pkt_drop(struct sk_buff *skb, int code, int ipstats_mib_noroutes) 1815 { 1816 int type; 1817 switch (ipstats_mib_noroutes) { 1818 case IPSTATS_MIB_INNOROUTES: 1819 type = ipv6_addr_type(&ipv6_hdr(skb)->daddr); 1820 if (type == IPV6_ADDR_ANY || type == IPV6_ADDR_RESERVED) { 1821 IP6_INC_STATS(ip6_dst_idev(skb->dst), IPSTATS_MIB_INADDRERRORS); 1822 break; 1823 } 1824 /* FALLTHROUGH */ 1825 case IPSTATS_MIB_OUTNOROUTES: 1826 IP6_INC_STATS(ip6_dst_idev(skb->dst), ipstats_mib_noroutes); 1827 break; 1828 } 1829 icmpv6_send(skb, ICMPV6_DEST_UNREACH, code, 0, skb->dev); 1830 kfree_skb(skb); 1831 return 0; 1832 } 1833 1834 static int ip6_pkt_discard(struct sk_buff *skb) 1835 { 1836 return ip6_pkt_drop(skb, ICMPV6_NOROUTE, IPSTATS_MIB_INNOROUTES); 1837 } 1838 1839 static int ip6_pkt_discard_out(struct sk_buff *skb) 1840 { 1841 skb->dev = skb->dst->dev; 1842 return ip6_pkt_drop(skb, ICMPV6_NOROUTE, IPSTATS_MIB_OUTNOROUTES); 1843 } 1844 1845 #ifdef CONFIG_IPV6_MULTIPLE_TABLES 1846 1847 static int ip6_pkt_prohibit(struct sk_buff *skb) 1848 { 1849 return ip6_pkt_drop(skb, ICMPV6_ADM_PROHIBITED, IPSTATS_MIB_INNOROUTES); 1850 } 1851 1852 static int ip6_pkt_prohibit_out(struct sk_buff *skb) 1853 { 1854 skb->dev = skb->dst->dev; 1855 return ip6_pkt_drop(skb, ICMPV6_ADM_PROHIBITED, IPSTATS_MIB_OUTNOROUTES); 1856 } 1857 1858 #endif 1859 1860 /* 1861 * Allocate a dst for local (unicast / anycast) address. 1862 */ 1863 1864 struct rt6_info *addrconf_dst_alloc(struct inet6_dev *idev, 1865 const struct in6_addr *addr, 1866 int anycast) 1867 { 1868 struct net *net = dev_net(idev->dev); 1869 struct rt6_info *rt = ip6_dst_alloc(net->ipv6.ip6_dst_ops); 1870 1871 if (rt == NULL) 1872 return ERR_PTR(-ENOMEM); 1873 1874 dev_hold(net->loopback_dev); 1875 in6_dev_hold(idev); 1876 1877 rt->u.dst.flags = DST_HOST; 1878 rt->u.dst.input = ip6_input; 1879 rt->u.dst.output = ip6_output; 1880 rt->rt6i_dev = net->loopback_dev; 1881 rt->rt6i_idev = idev; 1882 rt->u.dst.metrics[RTAX_MTU-1] = ipv6_get_mtu(rt->rt6i_dev); 1883 rt->u.dst.metrics[RTAX_ADVMSS-1] = ipv6_advmss(net, dst_mtu(&rt->u.dst)); 1884 rt->u.dst.metrics[RTAX_HOPLIMIT-1] = -1; 1885 rt->u.dst.obsolete = -1; 1886 1887 rt->rt6i_flags = RTF_UP | RTF_NONEXTHOP; 1888 if (anycast) 1889 rt->rt6i_flags |= RTF_ANYCAST; 1890 else 1891 rt->rt6i_flags |= RTF_LOCAL; 1892 rt->rt6i_nexthop = ndisc_get_neigh(rt->rt6i_dev, &rt->rt6i_gateway); 1893 if (rt->rt6i_nexthop == NULL) { 1894 dst_free(&rt->u.dst); 1895 return ERR_PTR(-ENOMEM); 1896 } 1897 1898 ipv6_addr_copy(&rt->rt6i_dst.addr, addr); 1899 rt->rt6i_dst.plen = 128; 1900 rt->rt6i_table = fib6_get_table(net, RT6_TABLE_LOCAL); 1901 1902 atomic_set(&rt->u.dst.__refcnt, 1); 1903 1904 return rt; 1905 } 1906 1907 struct arg_dev_net { 1908 struct net_device *dev; 1909 struct net *net; 1910 }; 1911 1912 static int fib6_ifdown(struct rt6_info *rt, void *arg) 1913 { 1914 struct net_device *dev = ((struct arg_dev_net *)arg)->dev; 1915 struct net *net = ((struct arg_dev_net *)arg)->net; 1916 1917 if (((void *)rt->rt6i_dev == dev || dev == NULL) && 1918 rt != net->ipv6.ip6_null_entry) { 1919 RT6_TRACE("deleted by ifdown %p\n", rt); 1920 return -1; 1921 } 1922 return 0; 1923 } 1924 1925 void rt6_ifdown(struct net *net, struct net_device *dev) 1926 { 1927 struct arg_dev_net adn = { 1928 .dev = dev, 1929 .net = net, 1930 }; 1931 1932 fib6_clean_all(net, fib6_ifdown, 0, &adn); 1933 } 1934 1935 struct rt6_mtu_change_arg 1936 { 1937 struct net_device *dev; 1938 unsigned mtu; 1939 }; 1940 1941 static int rt6_mtu_change_route(struct rt6_info *rt, void *p_arg) 1942 { 1943 struct rt6_mtu_change_arg *arg = (struct rt6_mtu_change_arg *) p_arg; 1944 struct inet6_dev *idev; 1945 struct net *net = dev_net(arg->dev); 1946 1947 /* In IPv6 pmtu discovery is not optional, 1948 so that RTAX_MTU lock cannot disable it. 1949 We still use this lock to block changes 1950 caused by addrconf/ndisc. 1951 */ 1952 1953 idev = __in6_dev_get(arg->dev); 1954 if (idev == NULL) 1955 return 0; 1956 1957 /* For administrative MTU increase, there is no way to discover 1958 IPv6 PMTU increase, so PMTU increase should be updated here. 1959 Since RFC 1981 doesn't include administrative MTU increase 1960 update PMTU increase is a MUST. (i.e. jumbo frame) 1961 */ 1962 /* 1963 If new MTU is less than route PMTU, this new MTU will be the 1964 lowest MTU in the path, update the route PMTU to reflect PMTU 1965 decreases; if new MTU is greater than route PMTU, and the 1966 old MTU is the lowest MTU in the path, update the route PMTU 1967 to reflect the increase. In this case if the other nodes' MTU 1968 also have the lowest MTU, TOO BIG MESSAGE will be lead to 1969 PMTU discouvery. 1970 */ 1971 if (rt->rt6i_dev == arg->dev && 1972 !dst_metric_locked(&rt->u.dst, RTAX_MTU) && 1973 (dst_mtu(&rt->u.dst) >= arg->mtu || 1974 (dst_mtu(&rt->u.dst) < arg->mtu && 1975 dst_mtu(&rt->u.dst) == idev->cnf.mtu6))) { 1976 rt->u.dst.metrics[RTAX_MTU-1] = arg->mtu; 1977 rt->u.dst.metrics[RTAX_ADVMSS-1] = ipv6_advmss(net, arg->mtu); 1978 } 1979 return 0; 1980 } 1981 1982 void rt6_mtu_change(struct net_device *dev, unsigned mtu) 1983 { 1984 struct rt6_mtu_change_arg arg = { 1985 .dev = dev, 1986 .mtu = mtu, 1987 }; 1988 1989 fib6_clean_all(dev_net(dev), rt6_mtu_change_route, 0, &arg); 1990 } 1991 1992 static const struct nla_policy rtm_ipv6_policy[RTA_MAX+1] = { 1993 [RTA_GATEWAY] = { .len = sizeof(struct in6_addr) }, 1994 [RTA_OIF] = { .type = NLA_U32 }, 1995 [RTA_IIF] = { .type = NLA_U32 }, 1996 [RTA_PRIORITY] = { .type = NLA_U32 }, 1997 [RTA_METRICS] = { .type = NLA_NESTED }, 1998 }; 1999 2000 static int rtm_to_fib6_config(struct sk_buff *skb, struct nlmsghdr *nlh, 2001 struct fib6_config *cfg) 2002 { 2003 struct rtmsg *rtm; 2004 struct nlattr *tb[RTA_MAX+1]; 2005 int err; 2006 2007 err = nlmsg_parse(nlh, sizeof(*rtm), tb, RTA_MAX, rtm_ipv6_policy); 2008 if (err < 0) 2009 goto errout; 2010 2011 err = -EINVAL; 2012 rtm = nlmsg_data(nlh); 2013 memset(cfg, 0, sizeof(*cfg)); 2014 2015 cfg->fc_table = rtm->rtm_table; 2016 cfg->fc_dst_len = rtm->rtm_dst_len; 2017 cfg->fc_src_len = rtm->rtm_src_len; 2018 cfg->fc_flags = RTF_UP; 2019 cfg->fc_protocol = rtm->rtm_protocol; 2020 2021 if (rtm->rtm_type == RTN_UNREACHABLE) 2022 cfg->fc_flags |= RTF_REJECT; 2023 2024 cfg->fc_nlinfo.pid = NETLINK_CB(skb).pid; 2025 cfg->fc_nlinfo.nlh = nlh; 2026 cfg->fc_nlinfo.nl_net = sock_net(skb->sk); 2027 2028 if (tb[RTA_GATEWAY]) { 2029 nla_memcpy(&cfg->fc_gateway, tb[RTA_GATEWAY], 16); 2030 cfg->fc_flags |= RTF_GATEWAY; 2031 } 2032 2033 if (tb[RTA_DST]) { 2034 int plen = (rtm->rtm_dst_len + 7) >> 3; 2035 2036 if (nla_len(tb[RTA_DST]) < plen) 2037 goto errout; 2038 2039 nla_memcpy(&cfg->fc_dst, tb[RTA_DST], plen); 2040 } 2041 2042 if (tb[RTA_SRC]) { 2043 int plen = (rtm->rtm_src_len + 7) >> 3; 2044 2045 if (nla_len(tb[RTA_SRC]) < plen) 2046 goto errout; 2047 2048 nla_memcpy(&cfg->fc_src, tb[RTA_SRC], plen); 2049 } 2050 2051 if (tb[RTA_OIF]) 2052 cfg->fc_ifindex = nla_get_u32(tb[RTA_OIF]); 2053 2054 if (tb[RTA_PRIORITY]) 2055 cfg->fc_metric = nla_get_u32(tb[RTA_PRIORITY]); 2056 2057 if (tb[RTA_METRICS]) { 2058 cfg->fc_mx = nla_data(tb[RTA_METRICS]); 2059 cfg->fc_mx_len = nla_len(tb[RTA_METRICS]); 2060 } 2061 2062 if (tb[RTA_TABLE]) 2063 cfg->fc_table = nla_get_u32(tb[RTA_TABLE]); 2064 2065 err = 0; 2066 errout: 2067 return err; 2068 } 2069 2070 static int inet6_rtm_delroute(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg) 2071 { 2072 struct fib6_config cfg; 2073 int err; 2074 2075 err = rtm_to_fib6_config(skb, nlh, &cfg); 2076 if (err < 0) 2077 return err; 2078 2079 return ip6_route_del(&cfg); 2080 } 2081 2082 static int inet6_rtm_newroute(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg) 2083 { 2084 struct fib6_config cfg; 2085 int err; 2086 2087 err = rtm_to_fib6_config(skb, nlh, &cfg); 2088 if (err < 0) 2089 return err; 2090 2091 return ip6_route_add(&cfg); 2092 } 2093 2094 static inline size_t rt6_nlmsg_size(void) 2095 { 2096 return NLMSG_ALIGN(sizeof(struct rtmsg)) 2097 + nla_total_size(16) /* RTA_SRC */ 2098 + nla_total_size(16) /* RTA_DST */ 2099 + nla_total_size(16) /* RTA_GATEWAY */ 2100 + nla_total_size(16) /* RTA_PREFSRC */ 2101 + nla_total_size(4) /* RTA_TABLE */ 2102 + nla_total_size(4) /* RTA_IIF */ 2103 + nla_total_size(4) /* RTA_OIF */ 2104 + nla_total_size(4) /* RTA_PRIORITY */ 2105 + RTAX_MAX * nla_total_size(4) /* RTA_METRICS */ 2106 + nla_total_size(sizeof(struct rta_cacheinfo)); 2107 } 2108 2109 static int rt6_fill_node(struct sk_buff *skb, struct rt6_info *rt, 2110 struct in6_addr *dst, struct in6_addr *src, 2111 int iif, int type, u32 pid, u32 seq, 2112 int prefix, int nowait, unsigned int flags) 2113 { 2114 struct rtmsg *rtm; 2115 struct nlmsghdr *nlh; 2116 long expires; 2117 u32 table; 2118 2119 if (prefix) { /* user wants prefix routes only */ 2120 if (!(rt->rt6i_flags & RTF_PREFIX_RT)) { 2121 /* success since this is not a prefix route */ 2122 return 1; 2123 } 2124 } 2125 2126 nlh = nlmsg_put(skb, pid, seq, type, sizeof(*rtm), flags); 2127 if (nlh == NULL) 2128 return -EMSGSIZE; 2129 2130 rtm = nlmsg_data(nlh); 2131 rtm->rtm_family = AF_INET6; 2132 rtm->rtm_dst_len = rt->rt6i_dst.plen; 2133 rtm->rtm_src_len = rt->rt6i_src.plen; 2134 rtm->rtm_tos = 0; 2135 if (rt->rt6i_table) 2136 table = rt->rt6i_table->tb6_id; 2137 else 2138 table = RT6_TABLE_UNSPEC; 2139 rtm->rtm_table = table; 2140 NLA_PUT_U32(skb, RTA_TABLE, table); 2141 if (rt->rt6i_flags&RTF_REJECT) 2142 rtm->rtm_type = RTN_UNREACHABLE; 2143 else if (rt->rt6i_dev && (rt->rt6i_dev->flags&IFF_LOOPBACK)) 2144 rtm->rtm_type = RTN_LOCAL; 2145 else 2146 rtm->rtm_type = RTN_UNICAST; 2147 rtm->rtm_flags = 0; 2148 rtm->rtm_scope = RT_SCOPE_UNIVERSE; 2149 rtm->rtm_protocol = rt->rt6i_protocol; 2150 if (rt->rt6i_flags&RTF_DYNAMIC) 2151 rtm->rtm_protocol = RTPROT_REDIRECT; 2152 else if (rt->rt6i_flags & RTF_ADDRCONF) 2153 rtm->rtm_protocol = RTPROT_KERNEL; 2154 else if (rt->rt6i_flags&RTF_DEFAULT) 2155 rtm->rtm_protocol = RTPROT_RA; 2156 2157 if (rt->rt6i_flags&RTF_CACHE) 2158 rtm->rtm_flags |= RTM_F_CLONED; 2159 2160 if (dst) { 2161 NLA_PUT(skb, RTA_DST, 16, dst); 2162 rtm->rtm_dst_len = 128; 2163 } else if (rtm->rtm_dst_len) 2164 NLA_PUT(skb, RTA_DST, 16, &rt->rt6i_dst.addr); 2165 #ifdef CONFIG_IPV6_SUBTREES 2166 if (src) { 2167 NLA_PUT(skb, RTA_SRC, 16, src); 2168 rtm->rtm_src_len = 128; 2169 } else if (rtm->rtm_src_len) 2170 NLA_PUT(skb, RTA_SRC, 16, &rt->rt6i_src.addr); 2171 #endif 2172 if (iif) { 2173 #ifdef CONFIG_IPV6_MROUTE 2174 if (ipv6_addr_is_multicast(&rt->rt6i_dst.addr)) { 2175 int err = ip6mr_get_route(skb, rtm, nowait); 2176 if (err <= 0) { 2177 if (!nowait) { 2178 if (err == 0) 2179 return 0; 2180 goto nla_put_failure; 2181 } else { 2182 if (err == -EMSGSIZE) 2183 goto nla_put_failure; 2184 } 2185 } 2186 } else 2187 #endif 2188 NLA_PUT_U32(skb, RTA_IIF, iif); 2189 } else if (dst) { 2190 struct in6_addr saddr_buf; 2191 if (ipv6_dev_get_saddr(ip6_dst_idev(&rt->u.dst)->dev, 2192 dst, 0, &saddr_buf) == 0) 2193 NLA_PUT(skb, RTA_PREFSRC, 16, &saddr_buf); 2194 } 2195 2196 if (rtnetlink_put_metrics(skb, rt->u.dst.metrics) < 0) 2197 goto nla_put_failure; 2198 2199 if (rt->u.dst.neighbour) 2200 NLA_PUT(skb, RTA_GATEWAY, 16, &rt->u.dst.neighbour->primary_key); 2201 2202 if (rt->u.dst.dev) 2203 NLA_PUT_U32(skb, RTA_OIF, rt->rt6i_dev->ifindex); 2204 2205 NLA_PUT_U32(skb, RTA_PRIORITY, rt->rt6i_metric); 2206 2207 if (!(rt->rt6i_flags & RTF_EXPIRES)) 2208 expires = 0; 2209 else if (rt->rt6i_expires - jiffies < INT_MAX) 2210 expires = rt->rt6i_expires - jiffies; 2211 else 2212 expires = INT_MAX; 2213 2214 if (rtnl_put_cacheinfo(skb, &rt->u.dst, 0, 0, 0, 2215 expires, rt->u.dst.error) < 0) 2216 goto nla_put_failure; 2217 2218 return nlmsg_end(skb, nlh); 2219 2220 nla_put_failure: 2221 nlmsg_cancel(skb, nlh); 2222 return -EMSGSIZE; 2223 } 2224 2225 int rt6_dump_route(struct rt6_info *rt, void *p_arg) 2226 { 2227 struct rt6_rtnl_dump_arg *arg = (struct rt6_rtnl_dump_arg *) p_arg; 2228 int prefix; 2229 2230 if (nlmsg_len(arg->cb->nlh) >= sizeof(struct rtmsg)) { 2231 struct rtmsg *rtm = nlmsg_data(arg->cb->nlh); 2232 prefix = (rtm->rtm_flags & RTM_F_PREFIX) != 0; 2233 } else 2234 prefix = 0; 2235 2236 return rt6_fill_node(arg->skb, rt, NULL, NULL, 0, RTM_NEWROUTE, 2237 NETLINK_CB(arg->cb->skb).pid, arg->cb->nlh->nlmsg_seq, 2238 prefix, 0, NLM_F_MULTI); 2239 } 2240 2241 static int inet6_rtm_getroute(struct sk_buff *in_skb, struct nlmsghdr* nlh, void *arg) 2242 { 2243 struct net *net = sock_net(in_skb->sk); 2244 struct nlattr *tb[RTA_MAX+1]; 2245 struct rt6_info *rt; 2246 struct sk_buff *skb; 2247 struct rtmsg *rtm; 2248 struct flowi fl; 2249 int err, iif = 0; 2250 2251 err = nlmsg_parse(nlh, sizeof(*rtm), tb, RTA_MAX, rtm_ipv6_policy); 2252 if (err < 0) 2253 goto errout; 2254 2255 err = -EINVAL; 2256 memset(&fl, 0, sizeof(fl)); 2257 2258 if (tb[RTA_SRC]) { 2259 if (nla_len(tb[RTA_SRC]) < sizeof(struct in6_addr)) 2260 goto errout; 2261 2262 ipv6_addr_copy(&fl.fl6_src, nla_data(tb[RTA_SRC])); 2263 } 2264 2265 if (tb[RTA_DST]) { 2266 if (nla_len(tb[RTA_DST]) < sizeof(struct in6_addr)) 2267 goto errout; 2268 2269 ipv6_addr_copy(&fl.fl6_dst, nla_data(tb[RTA_DST])); 2270 } 2271 2272 if (tb[RTA_IIF]) 2273 iif = nla_get_u32(tb[RTA_IIF]); 2274 2275 if (tb[RTA_OIF]) 2276 fl.oif = nla_get_u32(tb[RTA_OIF]); 2277 2278 if (iif) { 2279 struct net_device *dev; 2280 dev = __dev_get_by_index(net, iif); 2281 if (!dev) { 2282 err = -ENODEV; 2283 goto errout; 2284 } 2285 } 2286 2287 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL); 2288 if (skb == NULL) { 2289 err = -ENOBUFS; 2290 goto errout; 2291 } 2292 2293 /* Reserve room for dummy headers, this skb can pass 2294 through good chunk of routing engine. 2295 */ 2296 skb_reset_mac_header(skb); 2297 skb_reserve(skb, MAX_HEADER + sizeof(struct ipv6hdr)); 2298 2299 rt = (struct rt6_info*) ip6_route_output(net, NULL, &fl); 2300 skb->dst = &rt->u.dst; 2301 2302 err = rt6_fill_node(skb, rt, &fl.fl6_dst, &fl.fl6_src, iif, 2303 RTM_NEWROUTE, NETLINK_CB(in_skb).pid, 2304 nlh->nlmsg_seq, 0, 0, 0); 2305 if (err < 0) { 2306 kfree_skb(skb); 2307 goto errout; 2308 } 2309 2310 err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).pid); 2311 errout: 2312 return err; 2313 } 2314 2315 void inet6_rt_notify(int event, struct rt6_info *rt, struct nl_info *info) 2316 { 2317 struct sk_buff *skb; 2318 struct net *net = info->nl_net; 2319 u32 seq; 2320 int err; 2321 2322 err = -ENOBUFS; 2323 seq = info->nlh != NULL ? info->nlh->nlmsg_seq : 0; 2324 2325 skb = nlmsg_new(rt6_nlmsg_size(), gfp_any()); 2326 if (skb == NULL) 2327 goto errout; 2328 2329 err = rt6_fill_node(skb, rt, NULL, NULL, 0, 2330 event, info->pid, seq, 0, 0, 0); 2331 if (err < 0) { 2332 /* -EMSGSIZE implies BUG in rt6_nlmsg_size() */ 2333 WARN_ON(err == -EMSGSIZE); 2334 kfree_skb(skb); 2335 goto errout; 2336 } 2337 err = rtnl_notify(skb, net, info->pid, RTNLGRP_IPV6_ROUTE, 2338 info->nlh, gfp_any()); 2339 errout: 2340 if (err < 0) 2341 rtnl_set_sk_err(net, RTNLGRP_IPV6_ROUTE, err); 2342 } 2343 2344 static int ip6_route_dev_notify(struct notifier_block *this, 2345 unsigned long event, void *data) 2346 { 2347 struct net_device *dev = (struct net_device *)data; 2348 struct net *net = dev_net(dev); 2349 2350 if (event == NETDEV_REGISTER && (dev->flags & IFF_LOOPBACK)) { 2351 net->ipv6.ip6_null_entry->u.dst.dev = dev; 2352 net->ipv6.ip6_null_entry->rt6i_idev = in6_dev_get(dev); 2353 #ifdef CONFIG_IPV6_MULTIPLE_TABLES 2354 net->ipv6.ip6_prohibit_entry->u.dst.dev = dev; 2355 net->ipv6.ip6_prohibit_entry->rt6i_idev = in6_dev_get(dev); 2356 net->ipv6.ip6_blk_hole_entry->u.dst.dev = dev; 2357 net->ipv6.ip6_blk_hole_entry->rt6i_idev = in6_dev_get(dev); 2358 #endif 2359 } 2360 2361 return NOTIFY_OK; 2362 } 2363 2364 /* 2365 * /proc 2366 */ 2367 2368 #ifdef CONFIG_PROC_FS 2369 2370 #define RT6_INFO_LEN (32 + 4 + 32 + 4 + 32 + 40 + 5 + 1) 2371 2372 struct rt6_proc_arg 2373 { 2374 char *buffer; 2375 int offset; 2376 int length; 2377 int skip; 2378 int len; 2379 }; 2380 2381 static int rt6_info_route(struct rt6_info *rt, void *p_arg) 2382 { 2383 struct seq_file *m = p_arg; 2384 2385 seq_printf(m, NIP6_SEQFMT " %02x ", NIP6(rt->rt6i_dst.addr), 2386 rt->rt6i_dst.plen); 2387 2388 #ifdef CONFIG_IPV6_SUBTREES 2389 seq_printf(m, NIP6_SEQFMT " %02x ", NIP6(rt->rt6i_src.addr), 2390 rt->rt6i_src.plen); 2391 #else 2392 seq_puts(m, "00000000000000000000000000000000 00 "); 2393 #endif 2394 2395 if (rt->rt6i_nexthop) { 2396 seq_printf(m, NIP6_SEQFMT, 2397 NIP6(*((struct in6_addr *)rt->rt6i_nexthop->primary_key))); 2398 } else { 2399 seq_puts(m, "00000000000000000000000000000000"); 2400 } 2401 seq_printf(m, " %08x %08x %08x %08x %8s\n", 2402 rt->rt6i_metric, atomic_read(&rt->u.dst.__refcnt), 2403 rt->u.dst.__use, rt->rt6i_flags, 2404 rt->rt6i_dev ? rt->rt6i_dev->name : ""); 2405 return 0; 2406 } 2407 2408 static int ipv6_route_show(struct seq_file *m, void *v) 2409 { 2410 struct net *net = (struct net *)m->private; 2411 fib6_clean_all(net, rt6_info_route, 0, m); 2412 return 0; 2413 } 2414 2415 static int ipv6_route_open(struct inode *inode, struct file *file) 2416 { 2417 return single_open_net(inode, file, ipv6_route_show); 2418 } 2419 2420 static const struct file_operations ipv6_route_proc_fops = { 2421 .owner = THIS_MODULE, 2422 .open = ipv6_route_open, 2423 .read = seq_read, 2424 .llseek = seq_lseek, 2425 .release = single_release_net, 2426 }; 2427 2428 static int rt6_stats_seq_show(struct seq_file *seq, void *v) 2429 { 2430 struct net *net = (struct net *)seq->private; 2431 seq_printf(seq, "%04x %04x %04x %04x %04x %04x %04x\n", 2432 net->ipv6.rt6_stats->fib_nodes, 2433 net->ipv6.rt6_stats->fib_route_nodes, 2434 net->ipv6.rt6_stats->fib_rt_alloc, 2435 net->ipv6.rt6_stats->fib_rt_entries, 2436 net->ipv6.rt6_stats->fib_rt_cache, 2437 atomic_read(&net->ipv6.ip6_dst_ops->entries), 2438 net->ipv6.rt6_stats->fib_discarded_routes); 2439 2440 return 0; 2441 } 2442 2443 static int rt6_stats_seq_open(struct inode *inode, struct file *file) 2444 { 2445 return single_open_net(inode, file, rt6_stats_seq_show); 2446 } 2447 2448 static const struct file_operations rt6_stats_seq_fops = { 2449 .owner = THIS_MODULE, 2450 .open = rt6_stats_seq_open, 2451 .read = seq_read, 2452 .llseek = seq_lseek, 2453 .release = single_release_net, 2454 }; 2455 #endif /* CONFIG_PROC_FS */ 2456 2457 #ifdef CONFIG_SYSCTL 2458 2459 static 2460 int ipv6_sysctl_rtcache_flush(ctl_table *ctl, int write, struct file * filp, 2461 void __user *buffer, size_t *lenp, loff_t *ppos) 2462 { 2463 struct net *net = current->nsproxy->net_ns; 2464 int delay = net->ipv6.sysctl.flush_delay; 2465 if (write) { 2466 proc_dointvec(ctl, write, filp, buffer, lenp, ppos); 2467 fib6_run_gc(delay <= 0 ? ~0UL : (unsigned long)delay, net); 2468 return 0; 2469 } else 2470 return -EINVAL; 2471 } 2472 2473 ctl_table ipv6_route_table_template[] = { 2474 { 2475 .procname = "flush", 2476 .data = &init_net.ipv6.sysctl.flush_delay, 2477 .maxlen = sizeof(int), 2478 .mode = 0200, 2479 .proc_handler = &ipv6_sysctl_rtcache_flush 2480 }, 2481 { 2482 .ctl_name = NET_IPV6_ROUTE_GC_THRESH, 2483 .procname = "gc_thresh", 2484 .data = &ip6_dst_ops_template.gc_thresh, 2485 .maxlen = sizeof(int), 2486 .mode = 0644, 2487 .proc_handler = &proc_dointvec, 2488 }, 2489 { 2490 .ctl_name = NET_IPV6_ROUTE_MAX_SIZE, 2491 .procname = "max_size", 2492 .data = &init_net.ipv6.sysctl.ip6_rt_max_size, 2493 .maxlen = sizeof(int), 2494 .mode = 0644, 2495 .proc_handler = &proc_dointvec, 2496 }, 2497 { 2498 .ctl_name = NET_IPV6_ROUTE_GC_MIN_INTERVAL, 2499 .procname = "gc_min_interval", 2500 .data = &init_net.ipv6.sysctl.ip6_rt_gc_min_interval, 2501 .maxlen = sizeof(int), 2502 .mode = 0644, 2503 .proc_handler = &proc_dointvec_jiffies, 2504 .strategy = &sysctl_jiffies, 2505 }, 2506 { 2507 .ctl_name = NET_IPV6_ROUTE_GC_TIMEOUT, 2508 .procname = "gc_timeout", 2509 .data = &init_net.ipv6.sysctl.ip6_rt_gc_timeout, 2510 .maxlen = sizeof(int), 2511 .mode = 0644, 2512 .proc_handler = &proc_dointvec_jiffies, 2513 .strategy = &sysctl_jiffies, 2514 }, 2515 { 2516 .ctl_name = NET_IPV6_ROUTE_GC_INTERVAL, 2517 .procname = "gc_interval", 2518 .data = &init_net.ipv6.sysctl.ip6_rt_gc_interval, 2519 .maxlen = sizeof(int), 2520 .mode = 0644, 2521 .proc_handler = &proc_dointvec_jiffies, 2522 .strategy = &sysctl_jiffies, 2523 }, 2524 { 2525 .ctl_name = NET_IPV6_ROUTE_GC_ELASTICITY, 2526 .procname = "gc_elasticity", 2527 .data = &init_net.ipv6.sysctl.ip6_rt_gc_elasticity, 2528 .maxlen = sizeof(int), 2529 .mode = 0644, 2530 .proc_handler = &proc_dointvec_jiffies, 2531 .strategy = &sysctl_jiffies, 2532 }, 2533 { 2534 .ctl_name = NET_IPV6_ROUTE_MTU_EXPIRES, 2535 .procname = "mtu_expires", 2536 .data = &init_net.ipv6.sysctl.ip6_rt_mtu_expires, 2537 .maxlen = sizeof(int), 2538 .mode = 0644, 2539 .proc_handler = &proc_dointvec_jiffies, 2540 .strategy = &sysctl_jiffies, 2541 }, 2542 { 2543 .ctl_name = NET_IPV6_ROUTE_MIN_ADVMSS, 2544 .procname = "min_adv_mss", 2545 .data = &init_net.ipv6.sysctl.ip6_rt_min_advmss, 2546 .maxlen = sizeof(int), 2547 .mode = 0644, 2548 .proc_handler = &proc_dointvec_jiffies, 2549 .strategy = &sysctl_jiffies, 2550 }, 2551 { 2552 .ctl_name = NET_IPV6_ROUTE_GC_MIN_INTERVAL_MS, 2553 .procname = "gc_min_interval_ms", 2554 .data = &init_net.ipv6.sysctl.ip6_rt_gc_min_interval, 2555 .maxlen = sizeof(int), 2556 .mode = 0644, 2557 .proc_handler = &proc_dointvec_ms_jiffies, 2558 .strategy = &sysctl_ms_jiffies, 2559 }, 2560 { .ctl_name = 0 } 2561 }; 2562 2563 struct ctl_table *ipv6_route_sysctl_init(struct net *net) 2564 { 2565 struct ctl_table *table; 2566 2567 table = kmemdup(ipv6_route_table_template, 2568 sizeof(ipv6_route_table_template), 2569 GFP_KERNEL); 2570 2571 if (table) { 2572 table[0].data = &net->ipv6.sysctl.flush_delay; 2573 table[1].data = &net->ipv6.ip6_dst_ops->gc_thresh; 2574 table[2].data = &net->ipv6.sysctl.ip6_rt_max_size; 2575 table[3].data = &net->ipv6.sysctl.ip6_rt_gc_min_interval; 2576 table[4].data = &net->ipv6.sysctl.ip6_rt_gc_timeout; 2577 table[5].data = &net->ipv6.sysctl.ip6_rt_gc_interval; 2578 table[6].data = &net->ipv6.sysctl.ip6_rt_gc_elasticity; 2579 table[7].data = &net->ipv6.sysctl.ip6_rt_mtu_expires; 2580 table[8].data = &net->ipv6.sysctl.ip6_rt_min_advmss; 2581 } 2582 2583 return table; 2584 } 2585 #endif 2586 2587 static int ip6_route_net_init(struct net *net) 2588 { 2589 int ret = -ENOMEM; 2590 2591 net->ipv6.ip6_dst_ops = kmemdup(&ip6_dst_ops_template, 2592 sizeof(*net->ipv6.ip6_dst_ops), 2593 GFP_KERNEL); 2594 if (!net->ipv6.ip6_dst_ops) 2595 goto out; 2596 net->ipv6.ip6_dst_ops->dst_net = hold_net(net); 2597 2598 net->ipv6.ip6_null_entry = kmemdup(&ip6_null_entry_template, 2599 sizeof(*net->ipv6.ip6_null_entry), 2600 GFP_KERNEL); 2601 if (!net->ipv6.ip6_null_entry) 2602 goto out_ip6_dst_ops; 2603 net->ipv6.ip6_null_entry->u.dst.path = 2604 (struct dst_entry *)net->ipv6.ip6_null_entry; 2605 net->ipv6.ip6_null_entry->u.dst.ops = net->ipv6.ip6_dst_ops; 2606 2607 #ifdef CONFIG_IPV6_MULTIPLE_TABLES 2608 net->ipv6.ip6_prohibit_entry = kmemdup(&ip6_prohibit_entry_template, 2609 sizeof(*net->ipv6.ip6_prohibit_entry), 2610 GFP_KERNEL); 2611 if (!net->ipv6.ip6_prohibit_entry) { 2612 kfree(net->ipv6.ip6_null_entry); 2613 goto out; 2614 } 2615 net->ipv6.ip6_prohibit_entry->u.dst.path = 2616 (struct dst_entry *)net->ipv6.ip6_prohibit_entry; 2617 net->ipv6.ip6_prohibit_entry->u.dst.ops = net->ipv6.ip6_dst_ops; 2618 2619 net->ipv6.ip6_blk_hole_entry = kmemdup(&ip6_blk_hole_entry_template, 2620 sizeof(*net->ipv6.ip6_blk_hole_entry), 2621 GFP_KERNEL); 2622 if (!net->ipv6.ip6_blk_hole_entry) { 2623 kfree(net->ipv6.ip6_null_entry); 2624 kfree(net->ipv6.ip6_prohibit_entry); 2625 goto out; 2626 } 2627 net->ipv6.ip6_blk_hole_entry->u.dst.path = 2628 (struct dst_entry *)net->ipv6.ip6_blk_hole_entry; 2629 net->ipv6.ip6_blk_hole_entry->u.dst.ops = net->ipv6.ip6_dst_ops; 2630 #endif 2631 2632 #ifdef CONFIG_PROC_FS 2633 proc_net_fops_create(net, "ipv6_route", 0, &ipv6_route_proc_fops); 2634 proc_net_fops_create(net, "rt6_stats", S_IRUGO, &rt6_stats_seq_fops); 2635 #endif 2636 net->ipv6.ip6_rt_gc_expire = 30*HZ; 2637 2638 ret = 0; 2639 out: 2640 return ret; 2641 2642 out_ip6_dst_ops: 2643 release_net(net->ipv6.ip6_dst_ops->dst_net); 2644 kfree(net->ipv6.ip6_dst_ops); 2645 goto out; 2646 } 2647 2648 static void ip6_route_net_exit(struct net *net) 2649 { 2650 #ifdef CONFIG_PROC_FS 2651 proc_net_remove(net, "ipv6_route"); 2652 proc_net_remove(net, "rt6_stats"); 2653 #endif 2654 kfree(net->ipv6.ip6_null_entry); 2655 #ifdef CONFIG_IPV6_MULTIPLE_TABLES 2656 kfree(net->ipv6.ip6_prohibit_entry); 2657 kfree(net->ipv6.ip6_blk_hole_entry); 2658 #endif 2659 release_net(net->ipv6.ip6_dst_ops->dst_net); 2660 kfree(net->ipv6.ip6_dst_ops); 2661 } 2662 2663 static struct pernet_operations ip6_route_net_ops = { 2664 .init = ip6_route_net_init, 2665 .exit = ip6_route_net_exit, 2666 }; 2667 2668 static struct notifier_block ip6_route_dev_notifier = { 2669 .notifier_call = ip6_route_dev_notify, 2670 .priority = 0, 2671 }; 2672 2673 int __init ip6_route_init(void) 2674 { 2675 int ret; 2676 2677 ret = -ENOMEM; 2678 ip6_dst_ops_template.kmem_cachep = 2679 kmem_cache_create("ip6_dst_cache", sizeof(struct rt6_info), 0, 2680 SLAB_HWCACHE_ALIGN, NULL); 2681 if (!ip6_dst_ops_template.kmem_cachep) 2682 goto out;; 2683 2684 ret = register_pernet_subsys(&ip6_route_net_ops); 2685 if (ret) 2686 goto out_kmem_cache; 2687 2688 /* Registering of the loopback is done before this portion of code, 2689 * the loopback reference in rt6_info will not be taken, do it 2690 * manually for init_net */ 2691 init_net.ipv6.ip6_null_entry->u.dst.dev = init_net.loopback_dev; 2692 init_net.ipv6.ip6_null_entry->rt6i_idev = in6_dev_get(init_net.loopback_dev); 2693 #ifdef CONFIG_IPV6_MULTIPLE_TABLES 2694 init_net.ipv6.ip6_prohibit_entry->u.dst.dev = init_net.loopback_dev; 2695 init_net.ipv6.ip6_prohibit_entry->rt6i_idev = in6_dev_get(init_net.loopback_dev); 2696 init_net.ipv6.ip6_blk_hole_entry->u.dst.dev = init_net.loopback_dev; 2697 init_net.ipv6.ip6_blk_hole_entry->rt6i_idev = in6_dev_get(init_net.loopback_dev); 2698 #endif 2699 ret = fib6_init(); 2700 if (ret) 2701 goto out_register_subsys; 2702 2703 ret = xfrm6_init(); 2704 if (ret) 2705 goto out_fib6_init; 2706 2707 ret = fib6_rules_init(); 2708 if (ret) 2709 goto xfrm6_init; 2710 2711 ret = -ENOBUFS; 2712 if (__rtnl_register(PF_INET6, RTM_NEWROUTE, inet6_rtm_newroute, NULL) || 2713 __rtnl_register(PF_INET6, RTM_DELROUTE, inet6_rtm_delroute, NULL) || 2714 __rtnl_register(PF_INET6, RTM_GETROUTE, inet6_rtm_getroute, NULL)) 2715 goto fib6_rules_init; 2716 2717 ret = register_netdevice_notifier(&ip6_route_dev_notifier); 2718 if (ret) 2719 goto fib6_rules_init; 2720 2721 out: 2722 return ret; 2723 2724 fib6_rules_init: 2725 fib6_rules_cleanup(); 2726 xfrm6_init: 2727 xfrm6_fini(); 2728 out_fib6_init: 2729 fib6_gc_cleanup(); 2730 out_register_subsys: 2731 unregister_pernet_subsys(&ip6_route_net_ops); 2732 out_kmem_cache: 2733 kmem_cache_destroy(ip6_dst_ops_template.kmem_cachep); 2734 goto out; 2735 } 2736 2737 void ip6_route_cleanup(void) 2738 { 2739 unregister_netdevice_notifier(&ip6_route_dev_notifier); 2740 fib6_rules_cleanup(); 2741 xfrm6_fini(); 2742 fib6_gc_cleanup(); 2743 unregister_pernet_subsys(&ip6_route_net_ops); 2744 kmem_cache_destroy(ip6_dst_ops_template.kmem_cachep); 2745 } 2746