1 /* 2 * Linux INET6 implementation 3 * Forwarding Information Database 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 /* 15 * Changes: 16 * Yuji SEKIYA @USAGI: Support default route on router node; 17 * remove ip6_null_entry from the top of 18 * routing table. 19 * Ville Nuorvala: Fixed routing subtrees. 20 */ 21 #include <linux/errno.h> 22 #include <linux/types.h> 23 #include <linux/net.h> 24 #include <linux/route.h> 25 #include <linux/netdevice.h> 26 #include <linux/in6.h> 27 #include <linux/init.h> 28 #include <linux/list.h> 29 #include <linux/slab.h> 30 31 #ifdef CONFIG_PROC_FS 32 #include <linux/proc_fs.h> 33 #endif 34 35 #include <net/ipv6.h> 36 #include <net/ndisc.h> 37 #include <net/addrconf.h> 38 39 #include <net/ip6_fib.h> 40 #include <net/ip6_route.h> 41 42 #define RT6_DEBUG 2 43 44 #if RT6_DEBUG >= 3 45 #define RT6_TRACE(x...) printk(KERN_DEBUG x) 46 #else 47 #define RT6_TRACE(x...) do { ; } while (0) 48 #endif 49 50 static struct kmem_cache * fib6_node_kmem __read_mostly; 51 52 enum fib_walk_state_t 53 { 54 #ifdef CONFIG_IPV6_SUBTREES 55 FWS_S, 56 #endif 57 FWS_L, 58 FWS_R, 59 FWS_C, 60 FWS_U 61 }; 62 63 struct fib6_cleaner_t 64 { 65 struct fib6_walker_t w; 66 struct net *net; 67 int (*func)(struct rt6_info *, void *arg); 68 void *arg; 69 }; 70 71 static DEFINE_RWLOCK(fib6_walker_lock); 72 73 #ifdef CONFIG_IPV6_SUBTREES 74 #define FWS_INIT FWS_S 75 #else 76 #define FWS_INIT FWS_L 77 #endif 78 79 static void fib6_prune_clones(struct net *net, struct fib6_node *fn, 80 struct rt6_info *rt); 81 static struct rt6_info *fib6_find_prefix(struct net *net, struct fib6_node *fn); 82 static struct fib6_node *fib6_repair_tree(struct net *net, struct fib6_node *fn); 83 static int fib6_walk(struct fib6_walker_t *w); 84 static int fib6_walk_continue(struct fib6_walker_t *w); 85 86 /* 87 * A routing update causes an increase of the serial number on the 88 * affected subtree. This allows for cached routes to be asynchronously 89 * tested when modifications are made to the destination cache as a 90 * result of redirects, path MTU changes, etc. 91 */ 92 93 static __u32 rt_sernum; 94 95 static void fib6_gc_timer_cb(unsigned long arg); 96 97 static LIST_HEAD(fib6_walkers); 98 #define FOR_WALKERS(w) list_for_each_entry(w, &fib6_walkers, lh) 99 100 static inline void fib6_walker_link(struct fib6_walker_t *w) 101 { 102 write_lock_bh(&fib6_walker_lock); 103 list_add(&w->lh, &fib6_walkers); 104 write_unlock_bh(&fib6_walker_lock); 105 } 106 107 static inline void fib6_walker_unlink(struct fib6_walker_t *w) 108 { 109 write_lock_bh(&fib6_walker_lock); 110 list_del(&w->lh); 111 write_unlock_bh(&fib6_walker_lock); 112 } 113 static __inline__ u32 fib6_new_sernum(void) 114 { 115 u32 n = ++rt_sernum; 116 if ((__s32)n <= 0) 117 rt_sernum = n = 1; 118 return n; 119 } 120 121 /* 122 * Auxiliary address test functions for the radix tree. 123 * 124 * These assume a 32bit processor (although it will work on 125 * 64bit processors) 126 */ 127 128 /* 129 * test bit 130 */ 131 132 static __inline__ __be32 addr_bit_set(void *token, int fn_bit) 133 { 134 __be32 *addr = token; 135 136 return htonl(1 << ((~fn_bit)&0x1F)) & addr[fn_bit>>5]; 137 } 138 139 static __inline__ struct fib6_node * node_alloc(void) 140 { 141 struct fib6_node *fn; 142 143 fn = kmem_cache_zalloc(fib6_node_kmem, GFP_ATOMIC); 144 145 return fn; 146 } 147 148 static __inline__ void node_free(struct fib6_node * fn) 149 { 150 kmem_cache_free(fib6_node_kmem, fn); 151 } 152 153 static __inline__ void rt6_release(struct rt6_info *rt) 154 { 155 if (atomic_dec_and_test(&rt->rt6i_ref)) 156 dst_free(&rt->u.dst); 157 } 158 159 static void fib6_link_table(struct net *net, struct fib6_table *tb) 160 { 161 unsigned int h; 162 163 /* 164 * Initialize table lock at a single place to give lockdep a key, 165 * tables aren't visible prior to being linked to the list. 166 */ 167 rwlock_init(&tb->tb6_lock); 168 169 h = tb->tb6_id & (FIB6_TABLE_HASHSZ - 1); 170 171 /* 172 * No protection necessary, this is the only list mutatation 173 * operation, tables never disappear once they exist. 174 */ 175 hlist_add_head_rcu(&tb->tb6_hlist, &net->ipv6.fib_table_hash[h]); 176 } 177 178 #ifdef CONFIG_IPV6_MULTIPLE_TABLES 179 180 static struct fib6_table *fib6_alloc_table(struct net *net, u32 id) 181 { 182 struct fib6_table *table; 183 184 table = kzalloc(sizeof(*table), GFP_ATOMIC); 185 if (table != NULL) { 186 table->tb6_id = id; 187 table->tb6_root.leaf = net->ipv6.ip6_null_entry; 188 table->tb6_root.fn_flags = RTN_ROOT | RTN_TL_ROOT | RTN_RTINFO; 189 } 190 191 return table; 192 } 193 194 struct fib6_table *fib6_new_table(struct net *net, u32 id) 195 { 196 struct fib6_table *tb; 197 198 if (id == 0) 199 id = RT6_TABLE_MAIN; 200 tb = fib6_get_table(net, id); 201 if (tb) 202 return tb; 203 204 tb = fib6_alloc_table(net, id); 205 if (tb != NULL) 206 fib6_link_table(net, tb); 207 208 return tb; 209 } 210 211 struct fib6_table *fib6_get_table(struct net *net, u32 id) 212 { 213 struct fib6_table *tb; 214 struct hlist_head *head; 215 struct hlist_node *node; 216 unsigned int h; 217 218 if (id == 0) 219 id = RT6_TABLE_MAIN; 220 h = id & (FIB6_TABLE_HASHSZ - 1); 221 rcu_read_lock(); 222 head = &net->ipv6.fib_table_hash[h]; 223 hlist_for_each_entry_rcu(tb, node, head, tb6_hlist) { 224 if (tb->tb6_id == id) { 225 rcu_read_unlock(); 226 return tb; 227 } 228 } 229 rcu_read_unlock(); 230 231 return NULL; 232 } 233 234 static void __net_init fib6_tables_init(struct net *net) 235 { 236 fib6_link_table(net, net->ipv6.fib6_main_tbl); 237 fib6_link_table(net, net->ipv6.fib6_local_tbl); 238 } 239 #else 240 241 struct fib6_table *fib6_new_table(struct net *net, u32 id) 242 { 243 return fib6_get_table(net, id); 244 } 245 246 struct fib6_table *fib6_get_table(struct net *net, u32 id) 247 { 248 return net->ipv6.fib6_main_tbl; 249 } 250 251 struct dst_entry *fib6_rule_lookup(struct net *net, struct flowi *fl, 252 int flags, pol_lookup_t lookup) 253 { 254 return (struct dst_entry *) lookup(net, net->ipv6.fib6_main_tbl, fl, flags); 255 } 256 257 static void __net_init fib6_tables_init(struct net *net) 258 { 259 fib6_link_table(net, net->ipv6.fib6_main_tbl); 260 } 261 262 #endif 263 264 static int fib6_dump_node(struct fib6_walker_t *w) 265 { 266 int res; 267 struct rt6_info *rt; 268 269 for (rt = w->leaf; rt; rt = rt->u.dst.rt6_next) { 270 res = rt6_dump_route(rt, w->args); 271 if (res < 0) { 272 /* Frame is full, suspend walking */ 273 w->leaf = rt; 274 return 1; 275 } 276 WARN_ON(res == 0); 277 } 278 w->leaf = NULL; 279 return 0; 280 } 281 282 static void fib6_dump_end(struct netlink_callback *cb) 283 { 284 struct fib6_walker_t *w = (void*)cb->args[2]; 285 286 if (w) { 287 if (cb->args[4]) { 288 cb->args[4] = 0; 289 fib6_walker_unlink(w); 290 } 291 cb->args[2] = 0; 292 kfree(w); 293 } 294 cb->done = (void*)cb->args[3]; 295 cb->args[1] = 3; 296 } 297 298 static int fib6_dump_done(struct netlink_callback *cb) 299 { 300 fib6_dump_end(cb); 301 return cb->done ? cb->done(cb) : 0; 302 } 303 304 static int fib6_dump_table(struct fib6_table *table, struct sk_buff *skb, 305 struct netlink_callback *cb) 306 { 307 struct fib6_walker_t *w; 308 int res; 309 310 w = (void *)cb->args[2]; 311 w->root = &table->tb6_root; 312 313 if (cb->args[4] == 0) { 314 w->count = 0; 315 w->skip = 0; 316 317 read_lock_bh(&table->tb6_lock); 318 res = fib6_walk(w); 319 read_unlock_bh(&table->tb6_lock); 320 if (res > 0) { 321 cb->args[4] = 1; 322 cb->args[5] = w->root->fn_sernum; 323 } 324 } else { 325 if (cb->args[5] != w->root->fn_sernum) { 326 /* Begin at the root if the tree changed */ 327 cb->args[5] = w->root->fn_sernum; 328 w->state = FWS_INIT; 329 w->node = w->root; 330 w->skip = w->count; 331 } else 332 w->skip = 0; 333 334 read_lock_bh(&table->tb6_lock); 335 res = fib6_walk_continue(w); 336 read_unlock_bh(&table->tb6_lock); 337 if (res <= 0) { 338 fib6_walker_unlink(w); 339 cb->args[4] = 0; 340 } 341 } 342 343 return res; 344 } 345 346 static int inet6_dump_fib(struct sk_buff *skb, struct netlink_callback *cb) 347 { 348 struct net *net = sock_net(skb->sk); 349 unsigned int h, s_h; 350 unsigned int e = 0, s_e; 351 struct rt6_rtnl_dump_arg arg; 352 struct fib6_walker_t *w; 353 struct fib6_table *tb; 354 struct hlist_node *node; 355 struct hlist_head *head; 356 int res = 0; 357 358 s_h = cb->args[0]; 359 s_e = cb->args[1]; 360 361 w = (void *)cb->args[2]; 362 if (w == NULL) { 363 /* New dump: 364 * 365 * 1. hook callback destructor. 366 */ 367 cb->args[3] = (long)cb->done; 368 cb->done = fib6_dump_done; 369 370 /* 371 * 2. allocate and initialize walker. 372 */ 373 w = kzalloc(sizeof(*w), GFP_ATOMIC); 374 if (w == NULL) 375 return -ENOMEM; 376 w->func = fib6_dump_node; 377 cb->args[2] = (long)w; 378 } 379 380 arg.skb = skb; 381 arg.cb = cb; 382 arg.net = net; 383 w->args = &arg; 384 385 for (h = s_h; h < FIB6_TABLE_HASHSZ; h++, s_e = 0) { 386 e = 0; 387 head = &net->ipv6.fib_table_hash[h]; 388 hlist_for_each_entry(tb, node, head, tb6_hlist) { 389 if (e < s_e) 390 goto next; 391 res = fib6_dump_table(tb, skb, cb); 392 if (res != 0) 393 goto out; 394 next: 395 e++; 396 } 397 } 398 out: 399 cb->args[1] = e; 400 cb->args[0] = h; 401 402 res = res < 0 ? res : skb->len; 403 if (res <= 0) 404 fib6_dump_end(cb); 405 return res; 406 } 407 408 /* 409 * Routing Table 410 * 411 * return the appropriate node for a routing tree "add" operation 412 * by either creating and inserting or by returning an existing 413 * node. 414 */ 415 416 static struct fib6_node * fib6_add_1(struct fib6_node *root, void *addr, 417 int addrlen, int plen, 418 int offset) 419 { 420 struct fib6_node *fn, *in, *ln; 421 struct fib6_node *pn = NULL; 422 struct rt6key *key; 423 int bit; 424 __be32 dir = 0; 425 __u32 sernum = fib6_new_sernum(); 426 427 RT6_TRACE("fib6_add_1\n"); 428 429 /* insert node in tree */ 430 431 fn = root; 432 433 do { 434 key = (struct rt6key *)((u8 *)fn->leaf + offset); 435 436 /* 437 * Prefix match 438 */ 439 if (plen < fn->fn_bit || 440 !ipv6_prefix_equal(&key->addr, addr, fn->fn_bit)) 441 goto insert_above; 442 443 /* 444 * Exact match ? 445 */ 446 447 if (plen == fn->fn_bit) { 448 /* clean up an intermediate node */ 449 if ((fn->fn_flags & RTN_RTINFO) == 0) { 450 rt6_release(fn->leaf); 451 fn->leaf = NULL; 452 } 453 454 fn->fn_sernum = sernum; 455 456 return fn; 457 } 458 459 /* 460 * We have more bits to go 461 */ 462 463 /* Try to walk down on tree. */ 464 fn->fn_sernum = sernum; 465 dir = addr_bit_set(addr, fn->fn_bit); 466 pn = fn; 467 fn = dir ? fn->right: fn->left; 468 } while (fn); 469 470 /* 471 * We walked to the bottom of tree. 472 * Create new leaf node without children. 473 */ 474 475 ln = node_alloc(); 476 477 if (ln == NULL) 478 return NULL; 479 ln->fn_bit = plen; 480 481 ln->parent = pn; 482 ln->fn_sernum = sernum; 483 484 if (dir) 485 pn->right = ln; 486 else 487 pn->left = ln; 488 489 return ln; 490 491 492 insert_above: 493 /* 494 * split since we don't have a common prefix anymore or 495 * we have a less significant route. 496 * we've to insert an intermediate node on the list 497 * this new node will point to the one we need to create 498 * and the current 499 */ 500 501 pn = fn->parent; 502 503 /* find 1st bit in difference between the 2 addrs. 504 505 See comment in __ipv6_addr_diff: bit may be an invalid value, 506 but if it is >= plen, the value is ignored in any case. 507 */ 508 509 bit = __ipv6_addr_diff(addr, &key->addr, addrlen); 510 511 /* 512 * (intermediate)[in] 513 * / \ 514 * (new leaf node)[ln] (old node)[fn] 515 */ 516 if (plen > bit) { 517 in = node_alloc(); 518 ln = node_alloc(); 519 520 if (in == NULL || ln == NULL) { 521 if (in) 522 node_free(in); 523 if (ln) 524 node_free(ln); 525 return NULL; 526 } 527 528 /* 529 * new intermediate node. 530 * RTN_RTINFO will 531 * be off since that an address that chooses one of 532 * the branches would not match less specific routes 533 * in the other branch 534 */ 535 536 in->fn_bit = bit; 537 538 in->parent = pn; 539 in->leaf = fn->leaf; 540 atomic_inc(&in->leaf->rt6i_ref); 541 542 in->fn_sernum = sernum; 543 544 /* update parent pointer */ 545 if (dir) 546 pn->right = in; 547 else 548 pn->left = in; 549 550 ln->fn_bit = plen; 551 552 ln->parent = in; 553 fn->parent = in; 554 555 ln->fn_sernum = sernum; 556 557 if (addr_bit_set(addr, bit)) { 558 in->right = ln; 559 in->left = fn; 560 } else { 561 in->left = ln; 562 in->right = fn; 563 } 564 } else { /* plen <= bit */ 565 566 /* 567 * (new leaf node)[ln] 568 * / \ 569 * (old node)[fn] NULL 570 */ 571 572 ln = node_alloc(); 573 574 if (ln == NULL) 575 return NULL; 576 577 ln->fn_bit = plen; 578 579 ln->parent = pn; 580 581 ln->fn_sernum = sernum; 582 583 if (dir) 584 pn->right = ln; 585 else 586 pn->left = ln; 587 588 if (addr_bit_set(&key->addr, plen)) 589 ln->right = fn; 590 else 591 ln->left = fn; 592 593 fn->parent = ln; 594 } 595 return ln; 596 } 597 598 /* 599 * Insert routing information in a node. 600 */ 601 602 static int fib6_add_rt2node(struct fib6_node *fn, struct rt6_info *rt, 603 struct nl_info *info) 604 { 605 struct rt6_info *iter = NULL; 606 struct rt6_info **ins; 607 608 ins = &fn->leaf; 609 610 for (iter = fn->leaf; iter; iter=iter->u.dst.rt6_next) { 611 /* 612 * Search for duplicates 613 */ 614 615 if (iter->rt6i_metric == rt->rt6i_metric) { 616 /* 617 * Same priority level 618 */ 619 620 if (iter->rt6i_dev == rt->rt6i_dev && 621 iter->rt6i_idev == rt->rt6i_idev && 622 ipv6_addr_equal(&iter->rt6i_gateway, 623 &rt->rt6i_gateway)) { 624 if (!(iter->rt6i_flags&RTF_EXPIRES)) 625 return -EEXIST; 626 iter->rt6i_expires = rt->rt6i_expires; 627 if (!(rt->rt6i_flags&RTF_EXPIRES)) { 628 iter->rt6i_flags &= ~RTF_EXPIRES; 629 iter->rt6i_expires = 0; 630 } 631 return -EEXIST; 632 } 633 } 634 635 if (iter->rt6i_metric > rt->rt6i_metric) 636 break; 637 638 ins = &iter->u.dst.rt6_next; 639 } 640 641 /* Reset round-robin state, if necessary */ 642 if (ins == &fn->leaf) 643 fn->rr_ptr = NULL; 644 645 /* 646 * insert node 647 */ 648 649 rt->u.dst.rt6_next = iter; 650 *ins = rt; 651 rt->rt6i_node = fn; 652 atomic_inc(&rt->rt6i_ref); 653 inet6_rt_notify(RTM_NEWROUTE, rt, info); 654 info->nl_net->ipv6.rt6_stats->fib_rt_entries++; 655 656 if ((fn->fn_flags & RTN_RTINFO) == 0) { 657 info->nl_net->ipv6.rt6_stats->fib_route_nodes++; 658 fn->fn_flags |= RTN_RTINFO; 659 } 660 661 return 0; 662 } 663 664 static __inline__ void fib6_start_gc(struct net *net, struct rt6_info *rt) 665 { 666 if (!timer_pending(&net->ipv6.ip6_fib_timer) && 667 (rt->rt6i_flags & (RTF_EXPIRES|RTF_CACHE))) 668 mod_timer(&net->ipv6.ip6_fib_timer, 669 jiffies + net->ipv6.sysctl.ip6_rt_gc_interval); 670 } 671 672 void fib6_force_start_gc(struct net *net) 673 { 674 if (!timer_pending(&net->ipv6.ip6_fib_timer)) 675 mod_timer(&net->ipv6.ip6_fib_timer, 676 jiffies + net->ipv6.sysctl.ip6_rt_gc_interval); 677 } 678 679 /* 680 * Add routing information to the routing tree. 681 * <destination addr>/<source addr> 682 * with source addr info in sub-trees 683 */ 684 685 int fib6_add(struct fib6_node *root, struct rt6_info *rt, struct nl_info *info) 686 { 687 struct fib6_node *fn, *pn = NULL; 688 int err = -ENOMEM; 689 690 fn = fib6_add_1(root, &rt->rt6i_dst.addr, sizeof(struct in6_addr), 691 rt->rt6i_dst.plen, offsetof(struct rt6_info, rt6i_dst)); 692 693 if (fn == NULL) 694 goto out; 695 696 pn = fn; 697 698 #ifdef CONFIG_IPV6_SUBTREES 699 if (rt->rt6i_src.plen) { 700 struct fib6_node *sn; 701 702 if (fn->subtree == NULL) { 703 struct fib6_node *sfn; 704 705 /* 706 * Create subtree. 707 * 708 * fn[main tree] 709 * | 710 * sfn[subtree root] 711 * \ 712 * sn[new leaf node] 713 */ 714 715 /* Create subtree root node */ 716 sfn = node_alloc(); 717 if (sfn == NULL) 718 goto st_failure; 719 720 sfn->leaf = info->nl_net->ipv6.ip6_null_entry; 721 atomic_inc(&info->nl_net->ipv6.ip6_null_entry->rt6i_ref); 722 sfn->fn_flags = RTN_ROOT; 723 sfn->fn_sernum = fib6_new_sernum(); 724 725 /* Now add the first leaf node to new subtree */ 726 727 sn = fib6_add_1(sfn, &rt->rt6i_src.addr, 728 sizeof(struct in6_addr), rt->rt6i_src.plen, 729 offsetof(struct rt6_info, rt6i_src)); 730 731 if (sn == NULL) { 732 /* If it is failed, discard just allocated 733 root, and then (in st_failure) stale node 734 in main tree. 735 */ 736 node_free(sfn); 737 goto st_failure; 738 } 739 740 /* Now link new subtree to main tree */ 741 sfn->parent = fn; 742 fn->subtree = sfn; 743 } else { 744 sn = fib6_add_1(fn->subtree, &rt->rt6i_src.addr, 745 sizeof(struct in6_addr), rt->rt6i_src.plen, 746 offsetof(struct rt6_info, rt6i_src)); 747 748 if (sn == NULL) 749 goto st_failure; 750 } 751 752 if (fn->leaf == NULL) { 753 fn->leaf = rt; 754 atomic_inc(&rt->rt6i_ref); 755 } 756 fn = sn; 757 } 758 #endif 759 760 err = fib6_add_rt2node(fn, rt, info); 761 762 if (err == 0) { 763 fib6_start_gc(info->nl_net, rt); 764 if (!(rt->rt6i_flags&RTF_CACHE)) 765 fib6_prune_clones(info->nl_net, pn, rt); 766 } 767 768 out: 769 if (err) { 770 #ifdef CONFIG_IPV6_SUBTREES 771 /* 772 * If fib6_add_1 has cleared the old leaf pointer in the 773 * super-tree leaf node we have to find a new one for it. 774 */ 775 if (pn != fn && pn->leaf == rt) { 776 pn->leaf = NULL; 777 atomic_dec(&rt->rt6i_ref); 778 } 779 if (pn != fn && !pn->leaf && !(pn->fn_flags & RTN_RTINFO)) { 780 pn->leaf = fib6_find_prefix(info->nl_net, pn); 781 #if RT6_DEBUG >= 2 782 if (!pn->leaf) { 783 WARN_ON(pn->leaf == NULL); 784 pn->leaf = info->nl_net->ipv6.ip6_null_entry; 785 } 786 #endif 787 atomic_inc(&pn->leaf->rt6i_ref); 788 } 789 #endif 790 dst_free(&rt->u.dst); 791 } 792 return err; 793 794 #ifdef CONFIG_IPV6_SUBTREES 795 /* Subtree creation failed, probably main tree node 796 is orphan. If it is, shoot it. 797 */ 798 st_failure: 799 if (fn && !(fn->fn_flags & (RTN_RTINFO|RTN_ROOT))) 800 fib6_repair_tree(info->nl_net, fn); 801 dst_free(&rt->u.dst); 802 return err; 803 #endif 804 } 805 806 /* 807 * Routing tree lookup 808 * 809 */ 810 811 struct lookup_args { 812 int offset; /* key offset on rt6_info */ 813 struct in6_addr *addr; /* search key */ 814 }; 815 816 static struct fib6_node * fib6_lookup_1(struct fib6_node *root, 817 struct lookup_args *args) 818 { 819 struct fib6_node *fn; 820 __be32 dir; 821 822 if (unlikely(args->offset == 0)) 823 return NULL; 824 825 /* 826 * Descend on a tree 827 */ 828 829 fn = root; 830 831 for (;;) { 832 struct fib6_node *next; 833 834 dir = addr_bit_set(args->addr, fn->fn_bit); 835 836 next = dir ? fn->right : fn->left; 837 838 if (next) { 839 fn = next; 840 continue; 841 } 842 843 break; 844 } 845 846 while(fn) { 847 if (FIB6_SUBTREE(fn) || fn->fn_flags & RTN_RTINFO) { 848 struct rt6key *key; 849 850 key = (struct rt6key *) ((u8 *) fn->leaf + 851 args->offset); 852 853 if (ipv6_prefix_equal(&key->addr, args->addr, key->plen)) { 854 #ifdef CONFIG_IPV6_SUBTREES 855 if (fn->subtree) 856 fn = fib6_lookup_1(fn->subtree, args + 1); 857 #endif 858 if (!fn || fn->fn_flags & RTN_RTINFO) 859 return fn; 860 } 861 } 862 863 if (fn->fn_flags & RTN_ROOT) 864 break; 865 866 fn = fn->parent; 867 } 868 869 return NULL; 870 } 871 872 struct fib6_node * fib6_lookup(struct fib6_node *root, struct in6_addr *daddr, 873 struct in6_addr *saddr) 874 { 875 struct fib6_node *fn; 876 struct lookup_args args[] = { 877 { 878 .offset = offsetof(struct rt6_info, rt6i_dst), 879 .addr = daddr, 880 }, 881 #ifdef CONFIG_IPV6_SUBTREES 882 { 883 .offset = offsetof(struct rt6_info, rt6i_src), 884 .addr = saddr, 885 }, 886 #endif 887 { 888 .offset = 0, /* sentinel */ 889 } 890 }; 891 892 fn = fib6_lookup_1(root, daddr ? args : args + 1); 893 894 if (fn == NULL || fn->fn_flags & RTN_TL_ROOT) 895 fn = root; 896 897 return fn; 898 } 899 900 /* 901 * Get node with specified destination prefix (and source prefix, 902 * if subtrees are used) 903 */ 904 905 906 static struct fib6_node * fib6_locate_1(struct fib6_node *root, 907 struct in6_addr *addr, 908 int plen, int offset) 909 { 910 struct fib6_node *fn; 911 912 for (fn = root; fn ; ) { 913 struct rt6key *key = (struct rt6key *)((u8 *)fn->leaf + offset); 914 915 /* 916 * Prefix match 917 */ 918 if (plen < fn->fn_bit || 919 !ipv6_prefix_equal(&key->addr, addr, fn->fn_bit)) 920 return NULL; 921 922 if (plen == fn->fn_bit) 923 return fn; 924 925 /* 926 * We have more bits to go 927 */ 928 if (addr_bit_set(addr, fn->fn_bit)) 929 fn = fn->right; 930 else 931 fn = fn->left; 932 } 933 return NULL; 934 } 935 936 struct fib6_node * fib6_locate(struct fib6_node *root, 937 struct in6_addr *daddr, int dst_len, 938 struct in6_addr *saddr, int src_len) 939 { 940 struct fib6_node *fn; 941 942 fn = fib6_locate_1(root, daddr, dst_len, 943 offsetof(struct rt6_info, rt6i_dst)); 944 945 #ifdef CONFIG_IPV6_SUBTREES 946 if (src_len) { 947 WARN_ON(saddr == NULL); 948 if (fn && fn->subtree) 949 fn = fib6_locate_1(fn->subtree, saddr, src_len, 950 offsetof(struct rt6_info, rt6i_src)); 951 } 952 #endif 953 954 if (fn && fn->fn_flags&RTN_RTINFO) 955 return fn; 956 957 return NULL; 958 } 959 960 961 /* 962 * Deletion 963 * 964 */ 965 966 static struct rt6_info *fib6_find_prefix(struct net *net, struct fib6_node *fn) 967 { 968 if (fn->fn_flags&RTN_ROOT) 969 return net->ipv6.ip6_null_entry; 970 971 while(fn) { 972 if(fn->left) 973 return fn->left->leaf; 974 975 if(fn->right) 976 return fn->right->leaf; 977 978 fn = FIB6_SUBTREE(fn); 979 } 980 return NULL; 981 } 982 983 /* 984 * Called to trim the tree of intermediate nodes when possible. "fn" 985 * is the node we want to try and remove. 986 */ 987 988 static struct fib6_node *fib6_repair_tree(struct net *net, 989 struct fib6_node *fn) 990 { 991 int children; 992 int nstate; 993 struct fib6_node *child, *pn; 994 struct fib6_walker_t *w; 995 int iter = 0; 996 997 for (;;) { 998 RT6_TRACE("fixing tree: plen=%d iter=%d\n", fn->fn_bit, iter); 999 iter++; 1000 1001 WARN_ON(fn->fn_flags & RTN_RTINFO); 1002 WARN_ON(fn->fn_flags & RTN_TL_ROOT); 1003 WARN_ON(fn->leaf != NULL); 1004 1005 children = 0; 1006 child = NULL; 1007 if (fn->right) child = fn->right, children |= 1; 1008 if (fn->left) child = fn->left, children |= 2; 1009 1010 if (children == 3 || FIB6_SUBTREE(fn) 1011 #ifdef CONFIG_IPV6_SUBTREES 1012 /* Subtree root (i.e. fn) may have one child */ 1013 || (children && fn->fn_flags&RTN_ROOT) 1014 #endif 1015 ) { 1016 fn->leaf = fib6_find_prefix(net, fn); 1017 #if RT6_DEBUG >= 2 1018 if (fn->leaf==NULL) { 1019 WARN_ON(!fn->leaf); 1020 fn->leaf = net->ipv6.ip6_null_entry; 1021 } 1022 #endif 1023 atomic_inc(&fn->leaf->rt6i_ref); 1024 return fn->parent; 1025 } 1026 1027 pn = fn->parent; 1028 #ifdef CONFIG_IPV6_SUBTREES 1029 if (FIB6_SUBTREE(pn) == fn) { 1030 WARN_ON(!(fn->fn_flags & RTN_ROOT)); 1031 FIB6_SUBTREE(pn) = NULL; 1032 nstate = FWS_L; 1033 } else { 1034 WARN_ON(fn->fn_flags & RTN_ROOT); 1035 #endif 1036 if (pn->right == fn) pn->right = child; 1037 else if (pn->left == fn) pn->left = child; 1038 #if RT6_DEBUG >= 2 1039 else 1040 WARN_ON(1); 1041 #endif 1042 if (child) 1043 child->parent = pn; 1044 nstate = FWS_R; 1045 #ifdef CONFIG_IPV6_SUBTREES 1046 } 1047 #endif 1048 1049 read_lock(&fib6_walker_lock); 1050 FOR_WALKERS(w) { 1051 if (child == NULL) { 1052 if (w->root == fn) { 1053 w->root = w->node = NULL; 1054 RT6_TRACE("W %p adjusted by delroot 1\n", w); 1055 } else if (w->node == fn) { 1056 RT6_TRACE("W %p adjusted by delnode 1, s=%d/%d\n", w, w->state, nstate); 1057 w->node = pn; 1058 w->state = nstate; 1059 } 1060 } else { 1061 if (w->root == fn) { 1062 w->root = child; 1063 RT6_TRACE("W %p adjusted by delroot 2\n", w); 1064 } 1065 if (w->node == fn) { 1066 w->node = child; 1067 if (children&2) { 1068 RT6_TRACE("W %p adjusted by delnode 2, s=%d\n", w, w->state); 1069 w->state = w->state>=FWS_R ? FWS_U : FWS_INIT; 1070 } else { 1071 RT6_TRACE("W %p adjusted by delnode 2, s=%d\n", w, w->state); 1072 w->state = w->state>=FWS_C ? FWS_U : FWS_INIT; 1073 } 1074 } 1075 } 1076 } 1077 read_unlock(&fib6_walker_lock); 1078 1079 node_free(fn); 1080 if (pn->fn_flags&RTN_RTINFO || FIB6_SUBTREE(pn)) 1081 return pn; 1082 1083 rt6_release(pn->leaf); 1084 pn->leaf = NULL; 1085 fn = pn; 1086 } 1087 } 1088 1089 static void fib6_del_route(struct fib6_node *fn, struct rt6_info **rtp, 1090 struct nl_info *info) 1091 { 1092 struct fib6_walker_t *w; 1093 struct rt6_info *rt = *rtp; 1094 struct net *net = info->nl_net; 1095 1096 RT6_TRACE("fib6_del_route\n"); 1097 1098 /* Unlink it */ 1099 *rtp = rt->u.dst.rt6_next; 1100 rt->rt6i_node = NULL; 1101 net->ipv6.rt6_stats->fib_rt_entries--; 1102 net->ipv6.rt6_stats->fib_discarded_routes++; 1103 1104 /* Reset round-robin state, if necessary */ 1105 if (fn->rr_ptr == rt) 1106 fn->rr_ptr = NULL; 1107 1108 /* Adjust walkers */ 1109 read_lock(&fib6_walker_lock); 1110 FOR_WALKERS(w) { 1111 if (w->state == FWS_C && w->leaf == rt) { 1112 RT6_TRACE("walker %p adjusted by delroute\n", w); 1113 w->leaf = rt->u.dst.rt6_next; 1114 if (w->leaf == NULL) 1115 w->state = FWS_U; 1116 } 1117 } 1118 read_unlock(&fib6_walker_lock); 1119 1120 rt->u.dst.rt6_next = NULL; 1121 1122 /* If it was last route, expunge its radix tree node */ 1123 if (fn->leaf == NULL) { 1124 fn->fn_flags &= ~RTN_RTINFO; 1125 net->ipv6.rt6_stats->fib_route_nodes--; 1126 fn = fib6_repair_tree(net, fn); 1127 } 1128 1129 if (atomic_read(&rt->rt6i_ref) != 1) { 1130 /* This route is used as dummy address holder in some split 1131 * nodes. It is not leaked, but it still holds other resources, 1132 * which must be released in time. So, scan ascendant nodes 1133 * and replace dummy references to this route with references 1134 * to still alive ones. 1135 */ 1136 while (fn) { 1137 if (!(fn->fn_flags&RTN_RTINFO) && fn->leaf == rt) { 1138 fn->leaf = fib6_find_prefix(net, fn); 1139 atomic_inc(&fn->leaf->rt6i_ref); 1140 rt6_release(rt); 1141 } 1142 fn = fn->parent; 1143 } 1144 /* No more references are possible at this point. */ 1145 BUG_ON(atomic_read(&rt->rt6i_ref) != 1); 1146 } 1147 1148 inet6_rt_notify(RTM_DELROUTE, rt, info); 1149 rt6_release(rt); 1150 } 1151 1152 int fib6_del(struct rt6_info *rt, struct nl_info *info) 1153 { 1154 struct net *net = info->nl_net; 1155 struct fib6_node *fn = rt->rt6i_node; 1156 struct rt6_info **rtp; 1157 1158 #if RT6_DEBUG >= 2 1159 if (rt->u.dst.obsolete>0) { 1160 WARN_ON(fn != NULL); 1161 return -ENOENT; 1162 } 1163 #endif 1164 if (fn == NULL || rt == net->ipv6.ip6_null_entry) 1165 return -ENOENT; 1166 1167 WARN_ON(!(fn->fn_flags & RTN_RTINFO)); 1168 1169 if (!(rt->rt6i_flags&RTF_CACHE)) { 1170 struct fib6_node *pn = fn; 1171 #ifdef CONFIG_IPV6_SUBTREES 1172 /* clones of this route might be in another subtree */ 1173 if (rt->rt6i_src.plen) { 1174 while (!(pn->fn_flags&RTN_ROOT)) 1175 pn = pn->parent; 1176 pn = pn->parent; 1177 } 1178 #endif 1179 fib6_prune_clones(info->nl_net, pn, rt); 1180 } 1181 1182 /* 1183 * Walk the leaf entries looking for ourself 1184 */ 1185 1186 for (rtp = &fn->leaf; *rtp; rtp = &(*rtp)->u.dst.rt6_next) { 1187 if (*rtp == rt) { 1188 fib6_del_route(fn, rtp, info); 1189 return 0; 1190 } 1191 } 1192 return -ENOENT; 1193 } 1194 1195 /* 1196 * Tree traversal function. 1197 * 1198 * Certainly, it is not interrupt safe. 1199 * However, it is internally reenterable wrt itself and fib6_add/fib6_del. 1200 * It means, that we can modify tree during walking 1201 * and use this function for garbage collection, clone pruning, 1202 * cleaning tree when a device goes down etc. etc. 1203 * 1204 * It guarantees that every node will be traversed, 1205 * and that it will be traversed only once. 1206 * 1207 * Callback function w->func may return: 1208 * 0 -> continue walking. 1209 * positive value -> walking is suspended (used by tree dumps, 1210 * and probably by gc, if it will be split to several slices) 1211 * negative value -> terminate walking. 1212 * 1213 * The function itself returns: 1214 * 0 -> walk is complete. 1215 * >0 -> walk is incomplete (i.e. suspended) 1216 * <0 -> walk is terminated by an error. 1217 */ 1218 1219 static int fib6_walk_continue(struct fib6_walker_t *w) 1220 { 1221 struct fib6_node *fn, *pn; 1222 1223 for (;;) { 1224 fn = w->node; 1225 if (fn == NULL) 1226 return 0; 1227 1228 if (w->prune && fn != w->root && 1229 fn->fn_flags&RTN_RTINFO && w->state < FWS_C) { 1230 w->state = FWS_C; 1231 w->leaf = fn->leaf; 1232 } 1233 switch (w->state) { 1234 #ifdef CONFIG_IPV6_SUBTREES 1235 case FWS_S: 1236 if (FIB6_SUBTREE(fn)) { 1237 w->node = FIB6_SUBTREE(fn); 1238 continue; 1239 } 1240 w->state = FWS_L; 1241 #endif 1242 case FWS_L: 1243 if (fn->left) { 1244 w->node = fn->left; 1245 w->state = FWS_INIT; 1246 continue; 1247 } 1248 w->state = FWS_R; 1249 case FWS_R: 1250 if (fn->right) { 1251 w->node = fn->right; 1252 w->state = FWS_INIT; 1253 continue; 1254 } 1255 w->state = FWS_C; 1256 w->leaf = fn->leaf; 1257 case FWS_C: 1258 if (w->leaf && fn->fn_flags&RTN_RTINFO) { 1259 int err; 1260 1261 if (w->count < w->skip) { 1262 w->count++; 1263 continue; 1264 } 1265 1266 err = w->func(w); 1267 if (err) 1268 return err; 1269 1270 w->count++; 1271 continue; 1272 } 1273 w->state = FWS_U; 1274 case FWS_U: 1275 if (fn == w->root) 1276 return 0; 1277 pn = fn->parent; 1278 w->node = pn; 1279 #ifdef CONFIG_IPV6_SUBTREES 1280 if (FIB6_SUBTREE(pn) == fn) { 1281 WARN_ON(!(fn->fn_flags & RTN_ROOT)); 1282 w->state = FWS_L; 1283 continue; 1284 } 1285 #endif 1286 if (pn->left == fn) { 1287 w->state = FWS_R; 1288 continue; 1289 } 1290 if (pn->right == fn) { 1291 w->state = FWS_C; 1292 w->leaf = w->node->leaf; 1293 continue; 1294 } 1295 #if RT6_DEBUG >= 2 1296 WARN_ON(1); 1297 #endif 1298 } 1299 } 1300 } 1301 1302 static int fib6_walk(struct fib6_walker_t *w) 1303 { 1304 int res; 1305 1306 w->state = FWS_INIT; 1307 w->node = w->root; 1308 1309 fib6_walker_link(w); 1310 res = fib6_walk_continue(w); 1311 if (res <= 0) 1312 fib6_walker_unlink(w); 1313 return res; 1314 } 1315 1316 static int fib6_clean_node(struct fib6_walker_t *w) 1317 { 1318 int res; 1319 struct rt6_info *rt; 1320 struct fib6_cleaner_t *c = container_of(w, struct fib6_cleaner_t, w); 1321 struct nl_info info = { 1322 .nl_net = c->net, 1323 }; 1324 1325 for (rt = w->leaf; rt; rt = rt->u.dst.rt6_next) { 1326 res = c->func(rt, c->arg); 1327 if (res < 0) { 1328 w->leaf = rt; 1329 res = fib6_del(rt, &info); 1330 if (res) { 1331 #if RT6_DEBUG >= 2 1332 printk(KERN_DEBUG "fib6_clean_node: del failed: rt=%p@%p err=%d\n", rt, rt->rt6i_node, res); 1333 #endif 1334 continue; 1335 } 1336 return 0; 1337 } 1338 WARN_ON(res != 0); 1339 } 1340 w->leaf = rt; 1341 return 0; 1342 } 1343 1344 /* 1345 * Convenient frontend to tree walker. 1346 * 1347 * func is called on each route. 1348 * It may return -1 -> delete this route. 1349 * 0 -> continue walking 1350 * 1351 * prune==1 -> only immediate children of node (certainly, 1352 * ignoring pure split nodes) will be scanned. 1353 */ 1354 1355 static void fib6_clean_tree(struct net *net, struct fib6_node *root, 1356 int (*func)(struct rt6_info *, void *arg), 1357 int prune, void *arg) 1358 { 1359 struct fib6_cleaner_t c; 1360 1361 c.w.root = root; 1362 c.w.func = fib6_clean_node; 1363 c.w.prune = prune; 1364 c.w.count = 0; 1365 c.w.skip = 0; 1366 c.func = func; 1367 c.arg = arg; 1368 c.net = net; 1369 1370 fib6_walk(&c.w); 1371 } 1372 1373 void fib6_clean_all(struct net *net, int (*func)(struct rt6_info *, void *arg), 1374 int prune, void *arg) 1375 { 1376 struct fib6_table *table; 1377 struct hlist_node *node; 1378 struct hlist_head *head; 1379 unsigned int h; 1380 1381 rcu_read_lock(); 1382 for (h = 0; h < FIB6_TABLE_HASHSZ; h++) { 1383 head = &net->ipv6.fib_table_hash[h]; 1384 hlist_for_each_entry_rcu(table, node, head, tb6_hlist) { 1385 write_lock_bh(&table->tb6_lock); 1386 fib6_clean_tree(net, &table->tb6_root, 1387 func, prune, arg); 1388 write_unlock_bh(&table->tb6_lock); 1389 } 1390 } 1391 rcu_read_unlock(); 1392 } 1393 1394 static int fib6_prune_clone(struct rt6_info *rt, void *arg) 1395 { 1396 if (rt->rt6i_flags & RTF_CACHE) { 1397 RT6_TRACE("pruning clone %p\n", rt); 1398 return -1; 1399 } 1400 1401 return 0; 1402 } 1403 1404 static void fib6_prune_clones(struct net *net, struct fib6_node *fn, 1405 struct rt6_info *rt) 1406 { 1407 fib6_clean_tree(net, fn, fib6_prune_clone, 1, rt); 1408 } 1409 1410 /* 1411 * Garbage collection 1412 */ 1413 1414 static struct fib6_gc_args 1415 { 1416 int timeout; 1417 int more; 1418 } gc_args; 1419 1420 static int fib6_age(struct rt6_info *rt, void *arg) 1421 { 1422 unsigned long now = jiffies; 1423 1424 /* 1425 * check addrconf expiration here. 1426 * Routes are expired even if they are in use. 1427 * 1428 * Also age clones. Note, that clones are aged out 1429 * only if they are not in use now. 1430 */ 1431 1432 if (rt->rt6i_flags&RTF_EXPIRES && rt->rt6i_expires) { 1433 if (time_after(now, rt->rt6i_expires)) { 1434 RT6_TRACE("expiring %p\n", rt); 1435 return -1; 1436 } 1437 gc_args.more++; 1438 } else if (rt->rt6i_flags & RTF_CACHE) { 1439 if (atomic_read(&rt->u.dst.__refcnt) == 0 && 1440 time_after_eq(now, rt->u.dst.lastuse + gc_args.timeout)) { 1441 RT6_TRACE("aging clone %p\n", rt); 1442 return -1; 1443 } else if ((rt->rt6i_flags & RTF_GATEWAY) && 1444 (!(rt->rt6i_nexthop->flags & NTF_ROUTER))) { 1445 RT6_TRACE("purging route %p via non-router but gateway\n", 1446 rt); 1447 return -1; 1448 } 1449 gc_args.more++; 1450 } 1451 1452 return 0; 1453 } 1454 1455 static DEFINE_SPINLOCK(fib6_gc_lock); 1456 1457 void fib6_run_gc(unsigned long expires, struct net *net) 1458 { 1459 if (expires != ~0UL) { 1460 spin_lock_bh(&fib6_gc_lock); 1461 gc_args.timeout = expires ? (int)expires : 1462 net->ipv6.sysctl.ip6_rt_gc_interval; 1463 } else { 1464 if (!spin_trylock_bh(&fib6_gc_lock)) { 1465 mod_timer(&net->ipv6.ip6_fib_timer, jiffies + HZ); 1466 return; 1467 } 1468 gc_args.timeout = net->ipv6.sysctl.ip6_rt_gc_interval; 1469 } 1470 1471 gc_args.more = icmp6_dst_gc(); 1472 1473 fib6_clean_all(net, fib6_age, 0, NULL); 1474 1475 if (gc_args.more) 1476 mod_timer(&net->ipv6.ip6_fib_timer, 1477 round_jiffies(jiffies 1478 + net->ipv6.sysctl.ip6_rt_gc_interval)); 1479 else 1480 del_timer(&net->ipv6.ip6_fib_timer); 1481 spin_unlock_bh(&fib6_gc_lock); 1482 } 1483 1484 static void fib6_gc_timer_cb(unsigned long arg) 1485 { 1486 fib6_run_gc(0, (struct net *)arg); 1487 } 1488 1489 static int __net_init fib6_net_init(struct net *net) 1490 { 1491 setup_timer(&net->ipv6.ip6_fib_timer, fib6_gc_timer_cb, (unsigned long)net); 1492 1493 net->ipv6.rt6_stats = kzalloc(sizeof(*net->ipv6.rt6_stats), GFP_KERNEL); 1494 if (!net->ipv6.rt6_stats) 1495 goto out_timer; 1496 1497 net->ipv6.fib_table_hash = kcalloc(FIB6_TABLE_HASHSZ, 1498 sizeof(*net->ipv6.fib_table_hash), 1499 GFP_KERNEL); 1500 if (!net->ipv6.fib_table_hash) 1501 goto out_rt6_stats; 1502 1503 net->ipv6.fib6_main_tbl = kzalloc(sizeof(*net->ipv6.fib6_main_tbl), 1504 GFP_KERNEL); 1505 if (!net->ipv6.fib6_main_tbl) 1506 goto out_fib_table_hash; 1507 1508 net->ipv6.fib6_main_tbl->tb6_id = RT6_TABLE_MAIN; 1509 net->ipv6.fib6_main_tbl->tb6_root.leaf = net->ipv6.ip6_null_entry; 1510 net->ipv6.fib6_main_tbl->tb6_root.fn_flags = 1511 RTN_ROOT | RTN_TL_ROOT | RTN_RTINFO; 1512 1513 #ifdef CONFIG_IPV6_MULTIPLE_TABLES 1514 net->ipv6.fib6_local_tbl = kzalloc(sizeof(*net->ipv6.fib6_local_tbl), 1515 GFP_KERNEL); 1516 if (!net->ipv6.fib6_local_tbl) 1517 goto out_fib6_main_tbl; 1518 net->ipv6.fib6_local_tbl->tb6_id = RT6_TABLE_LOCAL; 1519 net->ipv6.fib6_local_tbl->tb6_root.leaf = net->ipv6.ip6_null_entry; 1520 net->ipv6.fib6_local_tbl->tb6_root.fn_flags = 1521 RTN_ROOT | RTN_TL_ROOT | RTN_RTINFO; 1522 #endif 1523 fib6_tables_init(net); 1524 1525 return 0; 1526 1527 #ifdef CONFIG_IPV6_MULTIPLE_TABLES 1528 out_fib6_main_tbl: 1529 kfree(net->ipv6.fib6_main_tbl); 1530 #endif 1531 out_fib_table_hash: 1532 kfree(net->ipv6.fib_table_hash); 1533 out_rt6_stats: 1534 kfree(net->ipv6.rt6_stats); 1535 out_timer: 1536 return -ENOMEM; 1537 } 1538 1539 static void fib6_net_exit(struct net *net) 1540 { 1541 rt6_ifdown(net, NULL); 1542 del_timer_sync(&net->ipv6.ip6_fib_timer); 1543 1544 #ifdef CONFIG_IPV6_MULTIPLE_TABLES 1545 kfree(net->ipv6.fib6_local_tbl); 1546 #endif 1547 kfree(net->ipv6.fib6_main_tbl); 1548 kfree(net->ipv6.fib_table_hash); 1549 kfree(net->ipv6.rt6_stats); 1550 } 1551 1552 static struct pernet_operations fib6_net_ops = { 1553 .init = fib6_net_init, 1554 .exit = fib6_net_exit, 1555 }; 1556 1557 int __init fib6_init(void) 1558 { 1559 int ret = -ENOMEM; 1560 1561 fib6_node_kmem = kmem_cache_create("fib6_nodes", 1562 sizeof(struct fib6_node), 1563 0, SLAB_HWCACHE_ALIGN, 1564 NULL); 1565 if (!fib6_node_kmem) 1566 goto out; 1567 1568 ret = register_pernet_subsys(&fib6_net_ops); 1569 if (ret) 1570 goto out_kmem_cache_create; 1571 1572 ret = __rtnl_register(PF_INET6, RTM_GETROUTE, NULL, inet6_dump_fib); 1573 if (ret) 1574 goto out_unregister_subsys; 1575 out: 1576 return ret; 1577 1578 out_unregister_subsys: 1579 unregister_pernet_subsys(&fib6_net_ops); 1580 out_kmem_cache_create: 1581 kmem_cache_destroy(fib6_node_kmem); 1582 goto out; 1583 } 1584 1585 void fib6_gc_cleanup(void) 1586 { 1587 unregister_pernet_subsys(&fib6_net_ops); 1588 kmem_cache_destroy(fib6_node_kmem); 1589 } 1590