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 #if defined(__LITTLE_ENDIAN) 132 # define BITOP_BE32_SWIZZLE (0x1F & ~7) 133 #else 134 # define BITOP_BE32_SWIZZLE 0 135 #endif 136 137 static __inline__ __be32 addr_bit_set(void *token, int fn_bit) 138 { 139 __be32 *addr = token; 140 /* 141 * Here, 142 * 1 << ((~fn_bit ^ BITOP_BE32_SWIZZLE) & 0x1f) 143 * is optimized version of 144 * htonl(1 << ((~fn_bit)&0x1F)) 145 * See include/asm-generic/bitops/le.h. 146 */ 147 return (__force __be32)(1 << ((~fn_bit ^ BITOP_BE32_SWIZZLE) & 0x1f)) & 148 addr[fn_bit >> 5]; 149 } 150 151 static __inline__ struct fib6_node * node_alloc(void) 152 { 153 struct fib6_node *fn; 154 155 fn = kmem_cache_zalloc(fib6_node_kmem, GFP_ATOMIC); 156 157 return fn; 158 } 159 160 static __inline__ void node_free(struct fib6_node * fn) 161 { 162 kmem_cache_free(fib6_node_kmem, fn); 163 } 164 165 static __inline__ void rt6_release(struct rt6_info *rt) 166 { 167 if (atomic_dec_and_test(&rt->rt6i_ref)) 168 dst_free(&rt->u.dst); 169 } 170 171 static void fib6_link_table(struct net *net, struct fib6_table *tb) 172 { 173 unsigned int h; 174 175 /* 176 * Initialize table lock at a single place to give lockdep a key, 177 * tables aren't visible prior to being linked to the list. 178 */ 179 rwlock_init(&tb->tb6_lock); 180 181 h = tb->tb6_id & (FIB6_TABLE_HASHSZ - 1); 182 183 /* 184 * No protection necessary, this is the only list mutatation 185 * operation, tables never disappear once they exist. 186 */ 187 hlist_add_head_rcu(&tb->tb6_hlist, &net->ipv6.fib_table_hash[h]); 188 } 189 190 #ifdef CONFIG_IPV6_MULTIPLE_TABLES 191 192 static struct fib6_table *fib6_alloc_table(struct net *net, u32 id) 193 { 194 struct fib6_table *table; 195 196 table = kzalloc(sizeof(*table), GFP_ATOMIC); 197 if (table != NULL) { 198 table->tb6_id = id; 199 table->tb6_root.leaf = net->ipv6.ip6_null_entry; 200 table->tb6_root.fn_flags = RTN_ROOT | RTN_TL_ROOT | RTN_RTINFO; 201 } 202 203 return table; 204 } 205 206 struct fib6_table *fib6_new_table(struct net *net, u32 id) 207 { 208 struct fib6_table *tb; 209 210 if (id == 0) 211 id = RT6_TABLE_MAIN; 212 tb = fib6_get_table(net, id); 213 if (tb) 214 return tb; 215 216 tb = fib6_alloc_table(net, id); 217 if (tb != NULL) 218 fib6_link_table(net, tb); 219 220 return tb; 221 } 222 223 struct fib6_table *fib6_get_table(struct net *net, u32 id) 224 { 225 struct fib6_table *tb; 226 struct hlist_head *head; 227 struct hlist_node *node; 228 unsigned int h; 229 230 if (id == 0) 231 id = RT6_TABLE_MAIN; 232 h = id & (FIB6_TABLE_HASHSZ - 1); 233 rcu_read_lock(); 234 head = &net->ipv6.fib_table_hash[h]; 235 hlist_for_each_entry_rcu(tb, node, head, tb6_hlist) { 236 if (tb->tb6_id == id) { 237 rcu_read_unlock(); 238 return tb; 239 } 240 } 241 rcu_read_unlock(); 242 243 return NULL; 244 } 245 246 static void __net_init fib6_tables_init(struct net *net) 247 { 248 fib6_link_table(net, net->ipv6.fib6_main_tbl); 249 fib6_link_table(net, net->ipv6.fib6_local_tbl); 250 } 251 #else 252 253 struct fib6_table *fib6_new_table(struct net *net, u32 id) 254 { 255 return fib6_get_table(net, id); 256 } 257 258 struct fib6_table *fib6_get_table(struct net *net, u32 id) 259 { 260 return net->ipv6.fib6_main_tbl; 261 } 262 263 struct dst_entry *fib6_rule_lookup(struct net *net, struct flowi *fl, 264 int flags, pol_lookup_t lookup) 265 { 266 return (struct dst_entry *) lookup(net, net->ipv6.fib6_main_tbl, fl, flags); 267 } 268 269 static void __net_init fib6_tables_init(struct net *net) 270 { 271 fib6_link_table(net, net->ipv6.fib6_main_tbl); 272 } 273 274 #endif 275 276 static int fib6_dump_node(struct fib6_walker_t *w) 277 { 278 int res; 279 struct rt6_info *rt; 280 281 for (rt = w->leaf; rt; rt = rt->u.dst.rt6_next) { 282 res = rt6_dump_route(rt, w->args); 283 if (res < 0) { 284 /* Frame is full, suspend walking */ 285 w->leaf = rt; 286 return 1; 287 } 288 WARN_ON(res == 0); 289 } 290 w->leaf = NULL; 291 return 0; 292 } 293 294 static void fib6_dump_end(struct netlink_callback *cb) 295 { 296 struct fib6_walker_t *w = (void*)cb->args[2]; 297 298 if (w) { 299 if (cb->args[4]) { 300 cb->args[4] = 0; 301 fib6_walker_unlink(w); 302 } 303 cb->args[2] = 0; 304 kfree(w); 305 } 306 cb->done = (void*)cb->args[3]; 307 cb->args[1] = 3; 308 } 309 310 static int fib6_dump_done(struct netlink_callback *cb) 311 { 312 fib6_dump_end(cb); 313 return cb->done ? cb->done(cb) : 0; 314 } 315 316 static int fib6_dump_table(struct fib6_table *table, struct sk_buff *skb, 317 struct netlink_callback *cb) 318 { 319 struct fib6_walker_t *w; 320 int res; 321 322 w = (void *)cb->args[2]; 323 w->root = &table->tb6_root; 324 325 if (cb->args[4] == 0) { 326 w->count = 0; 327 w->skip = 0; 328 329 read_lock_bh(&table->tb6_lock); 330 res = fib6_walk(w); 331 read_unlock_bh(&table->tb6_lock); 332 if (res > 0) { 333 cb->args[4] = 1; 334 cb->args[5] = w->root->fn_sernum; 335 } 336 } else { 337 if (cb->args[5] != w->root->fn_sernum) { 338 /* Begin at the root if the tree changed */ 339 cb->args[5] = w->root->fn_sernum; 340 w->state = FWS_INIT; 341 w->node = w->root; 342 w->skip = w->count; 343 } else 344 w->skip = 0; 345 346 read_lock_bh(&table->tb6_lock); 347 res = fib6_walk_continue(w); 348 read_unlock_bh(&table->tb6_lock); 349 if (res <= 0) { 350 fib6_walker_unlink(w); 351 cb->args[4] = 0; 352 } 353 } 354 355 return res; 356 } 357 358 static int inet6_dump_fib(struct sk_buff *skb, struct netlink_callback *cb) 359 { 360 struct net *net = sock_net(skb->sk); 361 unsigned int h, s_h; 362 unsigned int e = 0, s_e; 363 struct rt6_rtnl_dump_arg arg; 364 struct fib6_walker_t *w; 365 struct fib6_table *tb; 366 struct hlist_node *node; 367 struct hlist_head *head; 368 int res = 0; 369 370 s_h = cb->args[0]; 371 s_e = cb->args[1]; 372 373 w = (void *)cb->args[2]; 374 if (w == NULL) { 375 /* New dump: 376 * 377 * 1. hook callback destructor. 378 */ 379 cb->args[3] = (long)cb->done; 380 cb->done = fib6_dump_done; 381 382 /* 383 * 2. allocate and initialize walker. 384 */ 385 w = kzalloc(sizeof(*w), GFP_ATOMIC); 386 if (w == NULL) 387 return -ENOMEM; 388 w->func = fib6_dump_node; 389 cb->args[2] = (long)w; 390 } 391 392 arg.skb = skb; 393 arg.cb = cb; 394 arg.net = net; 395 w->args = &arg; 396 397 for (h = s_h; h < FIB6_TABLE_HASHSZ; h++, s_e = 0) { 398 e = 0; 399 head = &net->ipv6.fib_table_hash[h]; 400 hlist_for_each_entry(tb, node, head, tb6_hlist) { 401 if (e < s_e) 402 goto next; 403 res = fib6_dump_table(tb, skb, cb); 404 if (res != 0) 405 goto out; 406 next: 407 e++; 408 } 409 } 410 out: 411 cb->args[1] = e; 412 cb->args[0] = h; 413 414 res = res < 0 ? res : skb->len; 415 if (res <= 0) 416 fib6_dump_end(cb); 417 return res; 418 } 419 420 /* 421 * Routing Table 422 * 423 * return the appropriate node for a routing tree "add" operation 424 * by either creating and inserting or by returning an existing 425 * node. 426 */ 427 428 static struct fib6_node * fib6_add_1(struct fib6_node *root, void *addr, 429 int addrlen, int plen, 430 int offset) 431 { 432 struct fib6_node *fn, *in, *ln; 433 struct fib6_node *pn = NULL; 434 struct rt6key *key; 435 int bit; 436 __be32 dir = 0; 437 __u32 sernum = fib6_new_sernum(); 438 439 RT6_TRACE("fib6_add_1\n"); 440 441 /* insert node in tree */ 442 443 fn = root; 444 445 do { 446 key = (struct rt6key *)((u8 *)fn->leaf + offset); 447 448 /* 449 * Prefix match 450 */ 451 if (plen < fn->fn_bit || 452 !ipv6_prefix_equal(&key->addr, addr, fn->fn_bit)) 453 goto insert_above; 454 455 /* 456 * Exact match ? 457 */ 458 459 if (plen == fn->fn_bit) { 460 /* clean up an intermediate node */ 461 if ((fn->fn_flags & RTN_RTINFO) == 0) { 462 rt6_release(fn->leaf); 463 fn->leaf = NULL; 464 } 465 466 fn->fn_sernum = sernum; 467 468 return fn; 469 } 470 471 /* 472 * We have more bits to go 473 */ 474 475 /* Try to walk down on tree. */ 476 fn->fn_sernum = sernum; 477 dir = addr_bit_set(addr, fn->fn_bit); 478 pn = fn; 479 fn = dir ? fn->right: fn->left; 480 } while (fn); 481 482 /* 483 * We walked to the bottom of tree. 484 * Create new leaf node without children. 485 */ 486 487 ln = node_alloc(); 488 489 if (ln == NULL) 490 return NULL; 491 ln->fn_bit = plen; 492 493 ln->parent = pn; 494 ln->fn_sernum = sernum; 495 496 if (dir) 497 pn->right = ln; 498 else 499 pn->left = ln; 500 501 return ln; 502 503 504 insert_above: 505 /* 506 * split since we don't have a common prefix anymore or 507 * we have a less significant route. 508 * we've to insert an intermediate node on the list 509 * this new node will point to the one we need to create 510 * and the current 511 */ 512 513 pn = fn->parent; 514 515 /* find 1st bit in difference between the 2 addrs. 516 517 See comment in __ipv6_addr_diff: bit may be an invalid value, 518 but if it is >= plen, the value is ignored in any case. 519 */ 520 521 bit = __ipv6_addr_diff(addr, &key->addr, addrlen); 522 523 /* 524 * (intermediate)[in] 525 * / \ 526 * (new leaf node)[ln] (old node)[fn] 527 */ 528 if (plen > bit) { 529 in = node_alloc(); 530 ln = node_alloc(); 531 532 if (in == NULL || ln == NULL) { 533 if (in) 534 node_free(in); 535 if (ln) 536 node_free(ln); 537 return NULL; 538 } 539 540 /* 541 * new intermediate node. 542 * RTN_RTINFO will 543 * be off since that an address that chooses one of 544 * the branches would not match less specific routes 545 * in the other branch 546 */ 547 548 in->fn_bit = bit; 549 550 in->parent = pn; 551 in->leaf = fn->leaf; 552 atomic_inc(&in->leaf->rt6i_ref); 553 554 in->fn_sernum = sernum; 555 556 /* update parent pointer */ 557 if (dir) 558 pn->right = in; 559 else 560 pn->left = in; 561 562 ln->fn_bit = plen; 563 564 ln->parent = in; 565 fn->parent = in; 566 567 ln->fn_sernum = sernum; 568 569 if (addr_bit_set(addr, bit)) { 570 in->right = ln; 571 in->left = fn; 572 } else { 573 in->left = ln; 574 in->right = fn; 575 } 576 } else { /* plen <= bit */ 577 578 /* 579 * (new leaf node)[ln] 580 * / \ 581 * (old node)[fn] NULL 582 */ 583 584 ln = node_alloc(); 585 586 if (ln == NULL) 587 return NULL; 588 589 ln->fn_bit = plen; 590 591 ln->parent = pn; 592 593 ln->fn_sernum = sernum; 594 595 if (dir) 596 pn->right = ln; 597 else 598 pn->left = ln; 599 600 if (addr_bit_set(&key->addr, plen)) 601 ln->right = fn; 602 else 603 ln->left = fn; 604 605 fn->parent = ln; 606 } 607 return ln; 608 } 609 610 /* 611 * Insert routing information in a node. 612 */ 613 614 static int fib6_add_rt2node(struct fib6_node *fn, struct rt6_info *rt, 615 struct nl_info *info) 616 { 617 struct rt6_info *iter = NULL; 618 struct rt6_info **ins; 619 620 ins = &fn->leaf; 621 622 for (iter = fn->leaf; iter; iter=iter->u.dst.rt6_next) { 623 /* 624 * Search for duplicates 625 */ 626 627 if (iter->rt6i_metric == rt->rt6i_metric) { 628 /* 629 * Same priority level 630 */ 631 632 if (iter->rt6i_dev == rt->rt6i_dev && 633 iter->rt6i_idev == rt->rt6i_idev && 634 ipv6_addr_equal(&iter->rt6i_gateway, 635 &rt->rt6i_gateway)) { 636 if (!(iter->rt6i_flags&RTF_EXPIRES)) 637 return -EEXIST; 638 iter->rt6i_expires = rt->rt6i_expires; 639 if (!(rt->rt6i_flags&RTF_EXPIRES)) { 640 iter->rt6i_flags &= ~RTF_EXPIRES; 641 iter->rt6i_expires = 0; 642 } 643 return -EEXIST; 644 } 645 } 646 647 if (iter->rt6i_metric > rt->rt6i_metric) 648 break; 649 650 ins = &iter->u.dst.rt6_next; 651 } 652 653 /* Reset round-robin state, if necessary */ 654 if (ins == &fn->leaf) 655 fn->rr_ptr = NULL; 656 657 /* 658 * insert node 659 */ 660 661 rt->u.dst.rt6_next = iter; 662 *ins = rt; 663 rt->rt6i_node = fn; 664 atomic_inc(&rt->rt6i_ref); 665 inet6_rt_notify(RTM_NEWROUTE, rt, info); 666 info->nl_net->ipv6.rt6_stats->fib_rt_entries++; 667 668 if ((fn->fn_flags & RTN_RTINFO) == 0) { 669 info->nl_net->ipv6.rt6_stats->fib_route_nodes++; 670 fn->fn_flags |= RTN_RTINFO; 671 } 672 673 return 0; 674 } 675 676 static __inline__ void fib6_start_gc(struct net *net, struct rt6_info *rt) 677 { 678 if (!timer_pending(&net->ipv6.ip6_fib_timer) && 679 (rt->rt6i_flags & (RTF_EXPIRES|RTF_CACHE))) 680 mod_timer(&net->ipv6.ip6_fib_timer, 681 jiffies + net->ipv6.sysctl.ip6_rt_gc_interval); 682 } 683 684 void fib6_force_start_gc(struct net *net) 685 { 686 if (!timer_pending(&net->ipv6.ip6_fib_timer)) 687 mod_timer(&net->ipv6.ip6_fib_timer, 688 jiffies + net->ipv6.sysctl.ip6_rt_gc_interval); 689 } 690 691 /* 692 * Add routing information to the routing tree. 693 * <destination addr>/<source addr> 694 * with source addr info in sub-trees 695 */ 696 697 int fib6_add(struct fib6_node *root, struct rt6_info *rt, struct nl_info *info) 698 { 699 struct fib6_node *fn, *pn = NULL; 700 int err = -ENOMEM; 701 702 fn = fib6_add_1(root, &rt->rt6i_dst.addr, sizeof(struct in6_addr), 703 rt->rt6i_dst.plen, offsetof(struct rt6_info, rt6i_dst)); 704 705 if (fn == NULL) 706 goto out; 707 708 pn = fn; 709 710 #ifdef CONFIG_IPV6_SUBTREES 711 if (rt->rt6i_src.plen) { 712 struct fib6_node *sn; 713 714 if (fn->subtree == NULL) { 715 struct fib6_node *sfn; 716 717 /* 718 * Create subtree. 719 * 720 * fn[main tree] 721 * | 722 * sfn[subtree root] 723 * \ 724 * sn[new leaf node] 725 */ 726 727 /* Create subtree root node */ 728 sfn = node_alloc(); 729 if (sfn == NULL) 730 goto st_failure; 731 732 sfn->leaf = info->nl_net->ipv6.ip6_null_entry; 733 atomic_inc(&info->nl_net->ipv6.ip6_null_entry->rt6i_ref); 734 sfn->fn_flags = RTN_ROOT; 735 sfn->fn_sernum = fib6_new_sernum(); 736 737 /* Now add the first leaf node to new subtree */ 738 739 sn = fib6_add_1(sfn, &rt->rt6i_src.addr, 740 sizeof(struct in6_addr), rt->rt6i_src.plen, 741 offsetof(struct rt6_info, rt6i_src)); 742 743 if (sn == NULL) { 744 /* If it is failed, discard just allocated 745 root, and then (in st_failure) stale node 746 in main tree. 747 */ 748 node_free(sfn); 749 goto st_failure; 750 } 751 752 /* Now link new subtree to main tree */ 753 sfn->parent = fn; 754 fn->subtree = sfn; 755 } else { 756 sn = fib6_add_1(fn->subtree, &rt->rt6i_src.addr, 757 sizeof(struct in6_addr), rt->rt6i_src.plen, 758 offsetof(struct rt6_info, rt6i_src)); 759 760 if (sn == NULL) 761 goto st_failure; 762 } 763 764 if (fn->leaf == NULL) { 765 fn->leaf = rt; 766 atomic_inc(&rt->rt6i_ref); 767 } 768 fn = sn; 769 } 770 #endif 771 772 err = fib6_add_rt2node(fn, rt, info); 773 774 if (err == 0) { 775 fib6_start_gc(info->nl_net, rt); 776 if (!(rt->rt6i_flags&RTF_CACHE)) 777 fib6_prune_clones(info->nl_net, pn, rt); 778 } 779 780 out: 781 if (err) { 782 #ifdef CONFIG_IPV6_SUBTREES 783 /* 784 * If fib6_add_1 has cleared the old leaf pointer in the 785 * super-tree leaf node we have to find a new one for it. 786 */ 787 if (pn != fn && pn->leaf == rt) { 788 pn->leaf = NULL; 789 atomic_dec(&rt->rt6i_ref); 790 } 791 if (pn != fn && !pn->leaf && !(pn->fn_flags & RTN_RTINFO)) { 792 pn->leaf = fib6_find_prefix(info->nl_net, pn); 793 #if RT6_DEBUG >= 2 794 if (!pn->leaf) { 795 WARN_ON(pn->leaf == NULL); 796 pn->leaf = info->nl_net->ipv6.ip6_null_entry; 797 } 798 #endif 799 atomic_inc(&pn->leaf->rt6i_ref); 800 } 801 #endif 802 dst_free(&rt->u.dst); 803 } 804 return err; 805 806 #ifdef CONFIG_IPV6_SUBTREES 807 /* Subtree creation failed, probably main tree node 808 is orphan. If it is, shoot it. 809 */ 810 st_failure: 811 if (fn && !(fn->fn_flags & (RTN_RTINFO|RTN_ROOT))) 812 fib6_repair_tree(info->nl_net, fn); 813 dst_free(&rt->u.dst); 814 return err; 815 #endif 816 } 817 818 /* 819 * Routing tree lookup 820 * 821 */ 822 823 struct lookup_args { 824 int offset; /* key offset on rt6_info */ 825 struct in6_addr *addr; /* search key */ 826 }; 827 828 static struct fib6_node * fib6_lookup_1(struct fib6_node *root, 829 struct lookup_args *args) 830 { 831 struct fib6_node *fn; 832 __be32 dir; 833 834 if (unlikely(args->offset == 0)) 835 return NULL; 836 837 /* 838 * Descend on a tree 839 */ 840 841 fn = root; 842 843 for (;;) { 844 struct fib6_node *next; 845 846 dir = addr_bit_set(args->addr, fn->fn_bit); 847 848 next = dir ? fn->right : fn->left; 849 850 if (next) { 851 fn = next; 852 continue; 853 } 854 855 break; 856 } 857 858 while(fn) { 859 if (FIB6_SUBTREE(fn) || fn->fn_flags & RTN_RTINFO) { 860 struct rt6key *key; 861 862 key = (struct rt6key *) ((u8 *) fn->leaf + 863 args->offset); 864 865 if (ipv6_prefix_equal(&key->addr, args->addr, key->plen)) { 866 #ifdef CONFIG_IPV6_SUBTREES 867 if (fn->subtree) 868 fn = fib6_lookup_1(fn->subtree, args + 1); 869 #endif 870 if (!fn || fn->fn_flags & RTN_RTINFO) 871 return fn; 872 } 873 } 874 875 if (fn->fn_flags & RTN_ROOT) 876 break; 877 878 fn = fn->parent; 879 } 880 881 return NULL; 882 } 883 884 struct fib6_node * fib6_lookup(struct fib6_node *root, struct in6_addr *daddr, 885 struct in6_addr *saddr) 886 { 887 struct fib6_node *fn; 888 struct lookup_args args[] = { 889 { 890 .offset = offsetof(struct rt6_info, rt6i_dst), 891 .addr = daddr, 892 }, 893 #ifdef CONFIG_IPV6_SUBTREES 894 { 895 .offset = offsetof(struct rt6_info, rt6i_src), 896 .addr = saddr, 897 }, 898 #endif 899 { 900 .offset = 0, /* sentinel */ 901 } 902 }; 903 904 fn = fib6_lookup_1(root, daddr ? args : args + 1); 905 906 if (fn == NULL || fn->fn_flags & RTN_TL_ROOT) 907 fn = root; 908 909 return fn; 910 } 911 912 /* 913 * Get node with specified destination prefix (and source prefix, 914 * if subtrees are used) 915 */ 916 917 918 static struct fib6_node * fib6_locate_1(struct fib6_node *root, 919 struct in6_addr *addr, 920 int plen, int offset) 921 { 922 struct fib6_node *fn; 923 924 for (fn = root; fn ; ) { 925 struct rt6key *key = (struct rt6key *)((u8 *)fn->leaf + offset); 926 927 /* 928 * Prefix match 929 */ 930 if (plen < fn->fn_bit || 931 !ipv6_prefix_equal(&key->addr, addr, fn->fn_bit)) 932 return NULL; 933 934 if (plen == fn->fn_bit) 935 return fn; 936 937 /* 938 * We have more bits to go 939 */ 940 if (addr_bit_set(addr, fn->fn_bit)) 941 fn = fn->right; 942 else 943 fn = fn->left; 944 } 945 return NULL; 946 } 947 948 struct fib6_node * fib6_locate(struct fib6_node *root, 949 struct in6_addr *daddr, int dst_len, 950 struct in6_addr *saddr, int src_len) 951 { 952 struct fib6_node *fn; 953 954 fn = fib6_locate_1(root, daddr, dst_len, 955 offsetof(struct rt6_info, rt6i_dst)); 956 957 #ifdef CONFIG_IPV6_SUBTREES 958 if (src_len) { 959 WARN_ON(saddr == NULL); 960 if (fn && fn->subtree) 961 fn = fib6_locate_1(fn->subtree, saddr, src_len, 962 offsetof(struct rt6_info, rt6i_src)); 963 } 964 #endif 965 966 if (fn && fn->fn_flags&RTN_RTINFO) 967 return fn; 968 969 return NULL; 970 } 971 972 973 /* 974 * Deletion 975 * 976 */ 977 978 static struct rt6_info *fib6_find_prefix(struct net *net, struct fib6_node *fn) 979 { 980 if (fn->fn_flags&RTN_ROOT) 981 return net->ipv6.ip6_null_entry; 982 983 while(fn) { 984 if(fn->left) 985 return fn->left->leaf; 986 987 if(fn->right) 988 return fn->right->leaf; 989 990 fn = FIB6_SUBTREE(fn); 991 } 992 return NULL; 993 } 994 995 /* 996 * Called to trim the tree of intermediate nodes when possible. "fn" 997 * is the node we want to try and remove. 998 */ 999 1000 static struct fib6_node *fib6_repair_tree(struct net *net, 1001 struct fib6_node *fn) 1002 { 1003 int children; 1004 int nstate; 1005 struct fib6_node *child, *pn; 1006 struct fib6_walker_t *w; 1007 int iter = 0; 1008 1009 for (;;) { 1010 RT6_TRACE("fixing tree: plen=%d iter=%d\n", fn->fn_bit, iter); 1011 iter++; 1012 1013 WARN_ON(fn->fn_flags & RTN_RTINFO); 1014 WARN_ON(fn->fn_flags & RTN_TL_ROOT); 1015 WARN_ON(fn->leaf != NULL); 1016 1017 children = 0; 1018 child = NULL; 1019 if (fn->right) child = fn->right, children |= 1; 1020 if (fn->left) child = fn->left, children |= 2; 1021 1022 if (children == 3 || FIB6_SUBTREE(fn) 1023 #ifdef CONFIG_IPV6_SUBTREES 1024 /* Subtree root (i.e. fn) may have one child */ 1025 || (children && fn->fn_flags&RTN_ROOT) 1026 #endif 1027 ) { 1028 fn->leaf = fib6_find_prefix(net, fn); 1029 #if RT6_DEBUG >= 2 1030 if (fn->leaf==NULL) { 1031 WARN_ON(!fn->leaf); 1032 fn->leaf = net->ipv6.ip6_null_entry; 1033 } 1034 #endif 1035 atomic_inc(&fn->leaf->rt6i_ref); 1036 return fn->parent; 1037 } 1038 1039 pn = fn->parent; 1040 #ifdef CONFIG_IPV6_SUBTREES 1041 if (FIB6_SUBTREE(pn) == fn) { 1042 WARN_ON(!(fn->fn_flags & RTN_ROOT)); 1043 FIB6_SUBTREE(pn) = NULL; 1044 nstate = FWS_L; 1045 } else { 1046 WARN_ON(fn->fn_flags & RTN_ROOT); 1047 #endif 1048 if (pn->right == fn) pn->right = child; 1049 else if (pn->left == fn) pn->left = child; 1050 #if RT6_DEBUG >= 2 1051 else 1052 WARN_ON(1); 1053 #endif 1054 if (child) 1055 child->parent = pn; 1056 nstate = FWS_R; 1057 #ifdef CONFIG_IPV6_SUBTREES 1058 } 1059 #endif 1060 1061 read_lock(&fib6_walker_lock); 1062 FOR_WALKERS(w) { 1063 if (child == NULL) { 1064 if (w->root == fn) { 1065 w->root = w->node = NULL; 1066 RT6_TRACE("W %p adjusted by delroot 1\n", w); 1067 } else if (w->node == fn) { 1068 RT6_TRACE("W %p adjusted by delnode 1, s=%d/%d\n", w, w->state, nstate); 1069 w->node = pn; 1070 w->state = nstate; 1071 } 1072 } else { 1073 if (w->root == fn) { 1074 w->root = child; 1075 RT6_TRACE("W %p adjusted by delroot 2\n", w); 1076 } 1077 if (w->node == fn) { 1078 w->node = child; 1079 if (children&2) { 1080 RT6_TRACE("W %p adjusted by delnode 2, s=%d\n", w, w->state); 1081 w->state = w->state>=FWS_R ? FWS_U : FWS_INIT; 1082 } else { 1083 RT6_TRACE("W %p adjusted by delnode 2, s=%d\n", w, w->state); 1084 w->state = w->state>=FWS_C ? FWS_U : FWS_INIT; 1085 } 1086 } 1087 } 1088 } 1089 read_unlock(&fib6_walker_lock); 1090 1091 node_free(fn); 1092 if (pn->fn_flags&RTN_RTINFO || FIB6_SUBTREE(pn)) 1093 return pn; 1094 1095 rt6_release(pn->leaf); 1096 pn->leaf = NULL; 1097 fn = pn; 1098 } 1099 } 1100 1101 static void fib6_del_route(struct fib6_node *fn, struct rt6_info **rtp, 1102 struct nl_info *info) 1103 { 1104 struct fib6_walker_t *w; 1105 struct rt6_info *rt = *rtp; 1106 struct net *net = info->nl_net; 1107 1108 RT6_TRACE("fib6_del_route\n"); 1109 1110 /* Unlink it */ 1111 *rtp = rt->u.dst.rt6_next; 1112 rt->rt6i_node = NULL; 1113 net->ipv6.rt6_stats->fib_rt_entries--; 1114 net->ipv6.rt6_stats->fib_discarded_routes++; 1115 1116 /* Reset round-robin state, if necessary */ 1117 if (fn->rr_ptr == rt) 1118 fn->rr_ptr = NULL; 1119 1120 /* Adjust walkers */ 1121 read_lock(&fib6_walker_lock); 1122 FOR_WALKERS(w) { 1123 if (w->state == FWS_C && w->leaf == rt) { 1124 RT6_TRACE("walker %p adjusted by delroute\n", w); 1125 w->leaf = rt->u.dst.rt6_next; 1126 if (w->leaf == NULL) 1127 w->state = FWS_U; 1128 } 1129 } 1130 read_unlock(&fib6_walker_lock); 1131 1132 rt->u.dst.rt6_next = NULL; 1133 1134 /* If it was last route, expunge its radix tree node */ 1135 if (fn->leaf == NULL) { 1136 fn->fn_flags &= ~RTN_RTINFO; 1137 net->ipv6.rt6_stats->fib_route_nodes--; 1138 fn = fib6_repair_tree(net, fn); 1139 } 1140 1141 if (atomic_read(&rt->rt6i_ref) != 1) { 1142 /* This route is used as dummy address holder in some split 1143 * nodes. It is not leaked, but it still holds other resources, 1144 * which must be released in time. So, scan ascendant nodes 1145 * and replace dummy references to this route with references 1146 * to still alive ones. 1147 */ 1148 while (fn) { 1149 if (!(fn->fn_flags&RTN_RTINFO) && fn->leaf == rt) { 1150 fn->leaf = fib6_find_prefix(net, fn); 1151 atomic_inc(&fn->leaf->rt6i_ref); 1152 rt6_release(rt); 1153 } 1154 fn = fn->parent; 1155 } 1156 /* No more references are possible at this point. */ 1157 BUG_ON(atomic_read(&rt->rt6i_ref) != 1); 1158 } 1159 1160 inet6_rt_notify(RTM_DELROUTE, rt, info); 1161 rt6_release(rt); 1162 } 1163 1164 int fib6_del(struct rt6_info *rt, struct nl_info *info) 1165 { 1166 struct net *net = info->nl_net; 1167 struct fib6_node *fn = rt->rt6i_node; 1168 struct rt6_info **rtp; 1169 1170 #if RT6_DEBUG >= 2 1171 if (rt->u.dst.obsolete>0) { 1172 WARN_ON(fn != NULL); 1173 return -ENOENT; 1174 } 1175 #endif 1176 if (fn == NULL || rt == net->ipv6.ip6_null_entry) 1177 return -ENOENT; 1178 1179 WARN_ON(!(fn->fn_flags & RTN_RTINFO)); 1180 1181 if (!(rt->rt6i_flags&RTF_CACHE)) { 1182 struct fib6_node *pn = fn; 1183 #ifdef CONFIG_IPV6_SUBTREES 1184 /* clones of this route might be in another subtree */ 1185 if (rt->rt6i_src.plen) { 1186 while (!(pn->fn_flags&RTN_ROOT)) 1187 pn = pn->parent; 1188 pn = pn->parent; 1189 } 1190 #endif 1191 fib6_prune_clones(info->nl_net, pn, rt); 1192 } 1193 1194 /* 1195 * Walk the leaf entries looking for ourself 1196 */ 1197 1198 for (rtp = &fn->leaf; *rtp; rtp = &(*rtp)->u.dst.rt6_next) { 1199 if (*rtp == rt) { 1200 fib6_del_route(fn, rtp, info); 1201 return 0; 1202 } 1203 } 1204 return -ENOENT; 1205 } 1206 1207 /* 1208 * Tree traversal function. 1209 * 1210 * Certainly, it is not interrupt safe. 1211 * However, it is internally reenterable wrt itself and fib6_add/fib6_del. 1212 * It means, that we can modify tree during walking 1213 * and use this function for garbage collection, clone pruning, 1214 * cleaning tree when a device goes down etc. etc. 1215 * 1216 * It guarantees that every node will be traversed, 1217 * and that it will be traversed only once. 1218 * 1219 * Callback function w->func may return: 1220 * 0 -> continue walking. 1221 * positive value -> walking is suspended (used by tree dumps, 1222 * and probably by gc, if it will be split to several slices) 1223 * negative value -> terminate walking. 1224 * 1225 * The function itself returns: 1226 * 0 -> walk is complete. 1227 * >0 -> walk is incomplete (i.e. suspended) 1228 * <0 -> walk is terminated by an error. 1229 */ 1230 1231 static int fib6_walk_continue(struct fib6_walker_t *w) 1232 { 1233 struct fib6_node *fn, *pn; 1234 1235 for (;;) { 1236 fn = w->node; 1237 if (fn == NULL) 1238 return 0; 1239 1240 if (w->prune && fn != w->root && 1241 fn->fn_flags&RTN_RTINFO && w->state < FWS_C) { 1242 w->state = FWS_C; 1243 w->leaf = fn->leaf; 1244 } 1245 switch (w->state) { 1246 #ifdef CONFIG_IPV6_SUBTREES 1247 case FWS_S: 1248 if (FIB6_SUBTREE(fn)) { 1249 w->node = FIB6_SUBTREE(fn); 1250 continue; 1251 } 1252 w->state = FWS_L; 1253 #endif 1254 case FWS_L: 1255 if (fn->left) { 1256 w->node = fn->left; 1257 w->state = FWS_INIT; 1258 continue; 1259 } 1260 w->state = FWS_R; 1261 case FWS_R: 1262 if (fn->right) { 1263 w->node = fn->right; 1264 w->state = FWS_INIT; 1265 continue; 1266 } 1267 w->state = FWS_C; 1268 w->leaf = fn->leaf; 1269 case FWS_C: 1270 if (w->leaf && fn->fn_flags&RTN_RTINFO) { 1271 int err; 1272 1273 if (w->count < w->skip) { 1274 w->count++; 1275 continue; 1276 } 1277 1278 err = w->func(w); 1279 if (err) 1280 return err; 1281 1282 w->count++; 1283 continue; 1284 } 1285 w->state = FWS_U; 1286 case FWS_U: 1287 if (fn == w->root) 1288 return 0; 1289 pn = fn->parent; 1290 w->node = pn; 1291 #ifdef CONFIG_IPV6_SUBTREES 1292 if (FIB6_SUBTREE(pn) == fn) { 1293 WARN_ON(!(fn->fn_flags & RTN_ROOT)); 1294 w->state = FWS_L; 1295 continue; 1296 } 1297 #endif 1298 if (pn->left == fn) { 1299 w->state = FWS_R; 1300 continue; 1301 } 1302 if (pn->right == fn) { 1303 w->state = FWS_C; 1304 w->leaf = w->node->leaf; 1305 continue; 1306 } 1307 #if RT6_DEBUG >= 2 1308 WARN_ON(1); 1309 #endif 1310 } 1311 } 1312 } 1313 1314 static int fib6_walk(struct fib6_walker_t *w) 1315 { 1316 int res; 1317 1318 w->state = FWS_INIT; 1319 w->node = w->root; 1320 1321 fib6_walker_link(w); 1322 res = fib6_walk_continue(w); 1323 if (res <= 0) 1324 fib6_walker_unlink(w); 1325 return res; 1326 } 1327 1328 static int fib6_clean_node(struct fib6_walker_t *w) 1329 { 1330 int res; 1331 struct rt6_info *rt; 1332 struct fib6_cleaner_t *c = container_of(w, struct fib6_cleaner_t, w); 1333 struct nl_info info = { 1334 .nl_net = c->net, 1335 }; 1336 1337 for (rt = w->leaf; rt; rt = rt->u.dst.rt6_next) { 1338 res = c->func(rt, c->arg); 1339 if (res < 0) { 1340 w->leaf = rt; 1341 res = fib6_del(rt, &info); 1342 if (res) { 1343 #if RT6_DEBUG >= 2 1344 printk(KERN_DEBUG "fib6_clean_node: del failed: rt=%p@%p err=%d\n", rt, rt->rt6i_node, res); 1345 #endif 1346 continue; 1347 } 1348 return 0; 1349 } 1350 WARN_ON(res != 0); 1351 } 1352 w->leaf = rt; 1353 return 0; 1354 } 1355 1356 /* 1357 * Convenient frontend to tree walker. 1358 * 1359 * func is called on each route. 1360 * It may return -1 -> delete this route. 1361 * 0 -> continue walking 1362 * 1363 * prune==1 -> only immediate children of node (certainly, 1364 * ignoring pure split nodes) will be scanned. 1365 */ 1366 1367 static void fib6_clean_tree(struct net *net, struct fib6_node *root, 1368 int (*func)(struct rt6_info *, void *arg), 1369 int prune, void *arg) 1370 { 1371 struct fib6_cleaner_t c; 1372 1373 c.w.root = root; 1374 c.w.func = fib6_clean_node; 1375 c.w.prune = prune; 1376 c.w.count = 0; 1377 c.w.skip = 0; 1378 c.func = func; 1379 c.arg = arg; 1380 c.net = net; 1381 1382 fib6_walk(&c.w); 1383 } 1384 1385 void fib6_clean_all(struct net *net, int (*func)(struct rt6_info *, void *arg), 1386 int prune, void *arg) 1387 { 1388 struct fib6_table *table; 1389 struct hlist_node *node; 1390 struct hlist_head *head; 1391 unsigned int h; 1392 1393 rcu_read_lock(); 1394 for (h = 0; h < FIB6_TABLE_HASHSZ; h++) { 1395 head = &net->ipv6.fib_table_hash[h]; 1396 hlist_for_each_entry_rcu(table, node, head, tb6_hlist) { 1397 write_lock_bh(&table->tb6_lock); 1398 fib6_clean_tree(net, &table->tb6_root, 1399 func, prune, arg); 1400 write_unlock_bh(&table->tb6_lock); 1401 } 1402 } 1403 rcu_read_unlock(); 1404 } 1405 1406 static int fib6_prune_clone(struct rt6_info *rt, void *arg) 1407 { 1408 if (rt->rt6i_flags & RTF_CACHE) { 1409 RT6_TRACE("pruning clone %p\n", rt); 1410 return -1; 1411 } 1412 1413 return 0; 1414 } 1415 1416 static void fib6_prune_clones(struct net *net, struct fib6_node *fn, 1417 struct rt6_info *rt) 1418 { 1419 fib6_clean_tree(net, fn, fib6_prune_clone, 1, rt); 1420 } 1421 1422 /* 1423 * Garbage collection 1424 */ 1425 1426 static struct fib6_gc_args 1427 { 1428 int timeout; 1429 int more; 1430 } gc_args; 1431 1432 static int fib6_age(struct rt6_info *rt, void *arg) 1433 { 1434 unsigned long now = jiffies; 1435 1436 /* 1437 * check addrconf expiration here. 1438 * Routes are expired even if they are in use. 1439 * 1440 * Also age clones. Note, that clones are aged out 1441 * only if they are not in use now. 1442 */ 1443 1444 if (rt->rt6i_flags&RTF_EXPIRES && rt->rt6i_expires) { 1445 if (time_after(now, rt->rt6i_expires)) { 1446 RT6_TRACE("expiring %p\n", rt); 1447 return -1; 1448 } 1449 gc_args.more++; 1450 } else if (rt->rt6i_flags & RTF_CACHE) { 1451 if (atomic_read(&rt->u.dst.__refcnt) == 0 && 1452 time_after_eq(now, rt->u.dst.lastuse + gc_args.timeout)) { 1453 RT6_TRACE("aging clone %p\n", rt); 1454 return -1; 1455 } else if ((rt->rt6i_flags & RTF_GATEWAY) && 1456 (!(rt->rt6i_nexthop->flags & NTF_ROUTER))) { 1457 RT6_TRACE("purging route %p via non-router but gateway\n", 1458 rt); 1459 return -1; 1460 } 1461 gc_args.more++; 1462 } 1463 1464 return 0; 1465 } 1466 1467 static DEFINE_SPINLOCK(fib6_gc_lock); 1468 1469 void fib6_run_gc(unsigned long expires, struct net *net) 1470 { 1471 if (expires != ~0UL) { 1472 spin_lock_bh(&fib6_gc_lock); 1473 gc_args.timeout = expires ? (int)expires : 1474 net->ipv6.sysctl.ip6_rt_gc_interval; 1475 } else { 1476 if (!spin_trylock_bh(&fib6_gc_lock)) { 1477 mod_timer(&net->ipv6.ip6_fib_timer, jiffies + HZ); 1478 return; 1479 } 1480 gc_args.timeout = net->ipv6.sysctl.ip6_rt_gc_interval; 1481 } 1482 1483 gc_args.more = icmp6_dst_gc(); 1484 1485 fib6_clean_all(net, fib6_age, 0, NULL); 1486 1487 if (gc_args.more) 1488 mod_timer(&net->ipv6.ip6_fib_timer, 1489 round_jiffies(jiffies 1490 + net->ipv6.sysctl.ip6_rt_gc_interval)); 1491 else 1492 del_timer(&net->ipv6.ip6_fib_timer); 1493 spin_unlock_bh(&fib6_gc_lock); 1494 } 1495 1496 static void fib6_gc_timer_cb(unsigned long arg) 1497 { 1498 fib6_run_gc(0, (struct net *)arg); 1499 } 1500 1501 static int __net_init fib6_net_init(struct net *net) 1502 { 1503 setup_timer(&net->ipv6.ip6_fib_timer, fib6_gc_timer_cb, (unsigned long)net); 1504 1505 net->ipv6.rt6_stats = kzalloc(sizeof(*net->ipv6.rt6_stats), GFP_KERNEL); 1506 if (!net->ipv6.rt6_stats) 1507 goto out_timer; 1508 1509 net->ipv6.fib_table_hash = kcalloc(FIB6_TABLE_HASHSZ, 1510 sizeof(*net->ipv6.fib_table_hash), 1511 GFP_KERNEL); 1512 if (!net->ipv6.fib_table_hash) 1513 goto out_rt6_stats; 1514 1515 net->ipv6.fib6_main_tbl = kzalloc(sizeof(*net->ipv6.fib6_main_tbl), 1516 GFP_KERNEL); 1517 if (!net->ipv6.fib6_main_tbl) 1518 goto out_fib_table_hash; 1519 1520 net->ipv6.fib6_main_tbl->tb6_id = RT6_TABLE_MAIN; 1521 net->ipv6.fib6_main_tbl->tb6_root.leaf = net->ipv6.ip6_null_entry; 1522 net->ipv6.fib6_main_tbl->tb6_root.fn_flags = 1523 RTN_ROOT | RTN_TL_ROOT | RTN_RTINFO; 1524 1525 #ifdef CONFIG_IPV6_MULTIPLE_TABLES 1526 net->ipv6.fib6_local_tbl = kzalloc(sizeof(*net->ipv6.fib6_local_tbl), 1527 GFP_KERNEL); 1528 if (!net->ipv6.fib6_local_tbl) 1529 goto out_fib6_main_tbl; 1530 net->ipv6.fib6_local_tbl->tb6_id = RT6_TABLE_LOCAL; 1531 net->ipv6.fib6_local_tbl->tb6_root.leaf = net->ipv6.ip6_null_entry; 1532 net->ipv6.fib6_local_tbl->tb6_root.fn_flags = 1533 RTN_ROOT | RTN_TL_ROOT | RTN_RTINFO; 1534 #endif 1535 fib6_tables_init(net); 1536 1537 return 0; 1538 1539 #ifdef CONFIG_IPV6_MULTIPLE_TABLES 1540 out_fib6_main_tbl: 1541 kfree(net->ipv6.fib6_main_tbl); 1542 #endif 1543 out_fib_table_hash: 1544 kfree(net->ipv6.fib_table_hash); 1545 out_rt6_stats: 1546 kfree(net->ipv6.rt6_stats); 1547 out_timer: 1548 return -ENOMEM; 1549 } 1550 1551 static void fib6_net_exit(struct net *net) 1552 { 1553 rt6_ifdown(net, NULL); 1554 del_timer_sync(&net->ipv6.ip6_fib_timer); 1555 1556 #ifdef CONFIG_IPV6_MULTIPLE_TABLES 1557 kfree(net->ipv6.fib6_local_tbl); 1558 #endif 1559 kfree(net->ipv6.fib6_main_tbl); 1560 kfree(net->ipv6.fib_table_hash); 1561 kfree(net->ipv6.rt6_stats); 1562 } 1563 1564 static struct pernet_operations fib6_net_ops = { 1565 .init = fib6_net_init, 1566 .exit = fib6_net_exit, 1567 }; 1568 1569 int __init fib6_init(void) 1570 { 1571 int ret = -ENOMEM; 1572 1573 fib6_node_kmem = kmem_cache_create("fib6_nodes", 1574 sizeof(struct fib6_node), 1575 0, SLAB_HWCACHE_ALIGN, 1576 NULL); 1577 if (!fib6_node_kmem) 1578 goto out; 1579 1580 ret = register_pernet_subsys(&fib6_net_ops); 1581 if (ret) 1582 goto out_kmem_cache_create; 1583 1584 ret = __rtnl_register(PF_INET6, RTM_GETROUTE, NULL, inet6_dump_fib); 1585 if (ret) 1586 goto out_unregister_subsys; 1587 out: 1588 return ret; 1589 1590 out_unregister_subsys: 1591 unregister_pernet_subsys(&fib6_net_ops); 1592 out_kmem_cache_create: 1593 kmem_cache_destroy(fib6_node_kmem); 1594 goto out; 1595 } 1596 1597 void fib6_gc_cleanup(void) 1598 { 1599 unregister_pernet_subsys(&fib6_net_ops); 1600 kmem_cache_destroy(fib6_node_kmem); 1601 } 1602