1 /* 2 * Linux INET6 implementation 3 * Forwarding Information Database 4 * 5 * Authors: 6 * Pedro Roque <roque@di.fc.ul.pt> 7 * 8 * $Id: ip6_fib.c,v 1.25 2001/10/31 21:55:55 davem Exp $ 9 * 10 * This program is free software; you can redistribute it and/or 11 * modify it under the terms of the GNU General Public License 12 * as published by the Free Software Foundation; either version 13 * 2 of the License, or (at your option) any later version. 14 */ 15 16 /* 17 * Changes: 18 * Yuji SEKIYA @USAGI: Support default route on router node; 19 * remove ip6_null_entry from the top of 20 * routing table. 21 * Ville Nuorvala: Fixed routing subtrees. 22 */ 23 #include <linux/errno.h> 24 #include <linux/types.h> 25 #include <linux/net.h> 26 #include <linux/route.h> 27 #include <linux/netdevice.h> 28 #include <linux/in6.h> 29 #include <linux/init.h> 30 #include <linux/list.h> 31 32 #ifdef CONFIG_PROC_FS 33 #include <linux/proc_fs.h> 34 #endif 35 36 #include <net/ipv6.h> 37 #include <net/ndisc.h> 38 #include <net/addrconf.h> 39 40 #include <net/ip6_fib.h> 41 #include <net/ip6_route.h> 42 43 #define RT6_DEBUG 2 44 45 #if RT6_DEBUG >= 3 46 #define RT6_TRACE(x...) printk(KERN_DEBUG x) 47 #else 48 #define RT6_TRACE(x...) do { ; } while (0) 49 #endif 50 51 static struct kmem_cache * fib6_node_kmem __read_mostly; 52 53 enum fib_walk_state_t 54 { 55 #ifdef CONFIG_IPV6_SUBTREES 56 FWS_S, 57 #endif 58 FWS_L, 59 FWS_R, 60 FWS_C, 61 FWS_U 62 }; 63 64 struct fib6_cleaner_t 65 { 66 struct fib6_walker_t w; 67 struct net *net; 68 int (*func)(struct rt6_info *, void *arg); 69 void *arg; 70 }; 71 72 static DEFINE_RWLOCK(fib6_walker_lock); 73 74 #ifdef CONFIG_IPV6_SUBTREES 75 #define FWS_INIT FWS_S 76 #else 77 #define FWS_INIT FWS_L 78 #endif 79 80 static void fib6_prune_clones(struct net *net, struct fib6_node *fn, 81 struct rt6_info *rt); 82 static struct rt6_info *fib6_find_prefix(struct net *net, struct fib6_node *fn); 83 static struct fib6_node *fib6_repair_tree(struct net *net, struct fib6_node *fn); 84 static int fib6_walk(struct fib6_walker_t *w); 85 static int fib6_walk_continue(struct fib6_walker_t *w); 86 87 /* 88 * A routing update causes an increase of the serial number on the 89 * affected subtree. This allows for cached routes to be asynchronously 90 * tested when modifications are made to the destination cache as a 91 * result of redirects, path MTU changes, etc. 92 */ 93 94 static __u32 rt_sernum; 95 96 static void fib6_gc_timer_cb(unsigned long arg); 97 98 static struct fib6_walker_t fib6_walker_list = { 99 .prev = &fib6_walker_list, 100 .next = &fib6_walker_list, 101 }; 102 103 #define FOR_WALKERS(w) for ((w)=fib6_walker_list.next; (w) != &fib6_walker_list; (w)=(w)->next) 104 105 static inline void fib6_walker_link(struct fib6_walker_t *w) 106 { 107 write_lock_bh(&fib6_walker_lock); 108 w->next = fib6_walker_list.next; 109 w->prev = &fib6_walker_list; 110 w->next->prev = w; 111 w->prev->next = w; 112 write_unlock_bh(&fib6_walker_lock); 113 } 114 115 static inline void fib6_walker_unlink(struct fib6_walker_t *w) 116 { 117 write_lock_bh(&fib6_walker_lock); 118 w->next->prev = w->prev; 119 w->prev->next = w->next; 120 w->prev = w->next = w; 121 write_unlock_bh(&fib6_walker_lock); 122 } 123 static __inline__ u32 fib6_new_sernum(void) 124 { 125 u32 n = ++rt_sernum; 126 if ((__s32)n <= 0) 127 rt_sernum = n = 1; 128 return n; 129 } 130 131 /* 132 * Auxiliary address test functions for the radix tree. 133 * 134 * These assume a 32bit processor (although it will work on 135 * 64bit processors) 136 */ 137 138 /* 139 * test bit 140 */ 141 142 static __inline__ __be32 addr_bit_set(void *token, int fn_bit) 143 { 144 __be32 *addr = token; 145 146 return htonl(1 << ((~fn_bit)&0x1F)) & addr[fn_bit>>5]; 147 } 148 149 static __inline__ struct fib6_node * node_alloc(void) 150 { 151 struct fib6_node *fn; 152 153 fn = kmem_cache_zalloc(fib6_node_kmem, GFP_ATOMIC); 154 155 return fn; 156 } 157 158 static __inline__ void node_free(struct fib6_node * fn) 159 { 160 kmem_cache_free(fib6_node_kmem, fn); 161 } 162 163 static __inline__ void rt6_release(struct rt6_info *rt) 164 { 165 if (atomic_dec_and_test(&rt->rt6i_ref)) 166 dst_free(&rt->u.dst); 167 } 168 169 #ifdef CONFIG_IPV6_MULTIPLE_TABLES 170 #define FIB_TABLE_HASHSZ 256 171 #else 172 #define FIB_TABLE_HASHSZ 1 173 #endif 174 175 static void fib6_link_table(struct net *net, struct fib6_table *tb) 176 { 177 unsigned int h; 178 179 /* 180 * Initialize table lock at a single place to give lockdep a key, 181 * tables aren't visible prior to being linked to the list. 182 */ 183 rwlock_init(&tb->tb6_lock); 184 185 h = tb->tb6_id & (FIB_TABLE_HASHSZ - 1); 186 187 /* 188 * No protection necessary, this is the only list mutatation 189 * operation, tables never disappear once they exist. 190 */ 191 hlist_add_head_rcu(&tb->tb6_hlist, &net->ipv6.fib_table_hash[h]); 192 } 193 194 #ifdef CONFIG_IPV6_MULTIPLE_TABLES 195 196 static struct fib6_table *fib6_alloc_table(struct net *net, u32 id) 197 { 198 struct fib6_table *table; 199 200 table = kzalloc(sizeof(*table), GFP_ATOMIC); 201 if (table != NULL) { 202 table->tb6_id = id; 203 table->tb6_root.leaf = net->ipv6.ip6_null_entry; 204 table->tb6_root.fn_flags = RTN_ROOT | RTN_TL_ROOT | RTN_RTINFO; 205 } 206 207 return table; 208 } 209 210 struct fib6_table *fib6_new_table(struct net *net, u32 id) 211 { 212 struct fib6_table *tb; 213 214 if (id == 0) 215 id = RT6_TABLE_MAIN; 216 tb = fib6_get_table(net, id); 217 if (tb) 218 return tb; 219 220 tb = fib6_alloc_table(net, id); 221 if (tb != NULL) 222 fib6_link_table(net, tb); 223 224 return tb; 225 } 226 227 struct fib6_table *fib6_get_table(struct net *net, u32 id) 228 { 229 struct fib6_table *tb; 230 struct hlist_head *head; 231 struct hlist_node *node; 232 unsigned int h; 233 234 if (id == 0) 235 id = RT6_TABLE_MAIN; 236 h = id & (FIB_TABLE_HASHSZ - 1); 237 rcu_read_lock(); 238 head = &net->ipv6.fib_table_hash[h]; 239 hlist_for_each_entry_rcu(tb, node, head, tb6_hlist) { 240 if (tb->tb6_id == id) { 241 rcu_read_unlock(); 242 return tb; 243 } 244 } 245 rcu_read_unlock(); 246 247 return NULL; 248 } 249 250 static void fib6_tables_init(struct net *net) 251 { 252 fib6_link_table(net, net->ipv6.fib6_main_tbl); 253 fib6_link_table(net, net->ipv6.fib6_local_tbl); 254 } 255 #else 256 257 struct fib6_table *fib6_new_table(struct net *net, u32 id) 258 { 259 return fib6_get_table(net, id); 260 } 261 262 struct fib6_table *fib6_get_table(struct net *net, u32 id) 263 { 264 return net->ipv6.fib6_main_tbl; 265 } 266 267 struct dst_entry *fib6_rule_lookup(struct net *net, struct flowi *fl, 268 int flags, pol_lookup_t lookup) 269 { 270 return (struct dst_entry *) lookup(net, net->ipv6.fib6_main_tbl, fl, flags); 271 } 272 273 static void fib6_tables_init(struct net *net) 274 { 275 fib6_link_table(net, net->ipv6.fib6_main_tbl); 276 } 277 278 #endif 279 280 static int fib6_dump_node(struct fib6_walker_t *w) 281 { 282 int res; 283 struct rt6_info *rt; 284 285 for (rt = w->leaf; rt; rt = rt->u.dst.rt6_next) { 286 res = rt6_dump_route(rt, w->args); 287 if (res < 0) { 288 /* Frame is full, suspend walking */ 289 w->leaf = rt; 290 return 1; 291 } 292 BUG_TRAP(res!=0); 293 } 294 w->leaf = NULL; 295 return 0; 296 } 297 298 static void fib6_dump_end(struct netlink_callback *cb) 299 { 300 struct fib6_walker_t *w = (void*)cb->args[2]; 301 302 if (w) { 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 read_lock_bh(&table->tb6_lock); 327 res = fib6_walk(w); 328 read_unlock_bh(&table->tb6_lock); 329 if (res > 0) 330 cb->args[4] = 1; 331 } else { 332 read_lock_bh(&table->tb6_lock); 333 res = fib6_walk_continue(w); 334 read_unlock_bh(&table->tb6_lock); 335 if (res != 0) { 336 if (res < 0) 337 fib6_walker_unlink(w); 338 goto end; 339 } 340 fib6_walker_unlink(w); 341 cb->args[4] = 0; 342 } 343 end: 344 return res; 345 } 346 347 static int inet6_dump_fib(struct sk_buff *skb, struct netlink_callback *cb) 348 { 349 struct net *net = sock_net(skb->sk); 350 unsigned int h, s_h; 351 unsigned int e = 0, s_e; 352 struct rt6_rtnl_dump_arg arg; 353 struct fib6_walker_t *w; 354 struct fib6_table *tb; 355 struct hlist_node *node; 356 struct hlist_head *head; 357 int res = 0; 358 359 s_h = cb->args[0]; 360 s_e = cb->args[1]; 361 362 w = (void *)cb->args[2]; 363 if (w == NULL) { 364 /* New dump: 365 * 366 * 1. hook callback destructor. 367 */ 368 cb->args[3] = (long)cb->done; 369 cb->done = fib6_dump_done; 370 371 /* 372 * 2. allocate and initialize walker. 373 */ 374 w = kzalloc(sizeof(*w), GFP_ATOMIC); 375 if (w == NULL) 376 return -ENOMEM; 377 w->func = fib6_dump_node; 378 cb->args[2] = (long)w; 379 } 380 381 arg.skb = skb; 382 arg.cb = cb; 383 w->args = &arg; 384 385 for (h = s_h; h < FIB_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 (net->ipv6.ip6_fib_timer->expires == 0 && 667 (rt->rt6i_flags & (RTF_EXPIRES|RTF_CACHE))) 668 mod_timer(net->ipv6.ip6_fib_timer, jiffies + 669 net->ipv6.sysctl.ip6_rt_gc_interval); 670 } 671 672 void fib6_force_start_gc(struct net *net) 673 { 674 if (net->ipv6.ip6_fib_timer->expires == 0) 675 mod_timer(net->ipv6.ip6_fib_timer, jiffies + 676 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 BUG_TRAP(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 BUG_TRAP(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 BUG_TRAP(!(fn->fn_flags&RTN_RTINFO)); 1002 BUG_TRAP(!(fn->fn_flags&RTN_TL_ROOT)); 1003 BUG_TRAP(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 BUG_TRAP(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 BUG_TRAP(fn->fn_flags&RTN_ROOT); 1031 FIB6_SUBTREE(pn) = NULL; 1032 nstate = FWS_L; 1033 } else { 1034 BUG_TRAP(!(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 BUG_TRAP(0); 1040 #endif 1041 if (child) 1042 child->parent = pn; 1043 nstate = FWS_R; 1044 #ifdef CONFIG_IPV6_SUBTREES 1045 } 1046 #endif 1047 1048 read_lock(&fib6_walker_lock); 1049 FOR_WALKERS(w) { 1050 if (child == NULL) { 1051 if (w->root == fn) { 1052 w->root = w->node = NULL; 1053 RT6_TRACE("W %p adjusted by delroot 1\n", w); 1054 } else if (w->node == fn) { 1055 RT6_TRACE("W %p adjusted by delnode 1, s=%d/%d\n", w, w->state, nstate); 1056 w->node = pn; 1057 w->state = nstate; 1058 } 1059 } else { 1060 if (w->root == fn) { 1061 w->root = child; 1062 RT6_TRACE("W %p adjusted by delroot 2\n", w); 1063 } 1064 if (w->node == fn) { 1065 w->node = child; 1066 if (children&2) { 1067 RT6_TRACE("W %p adjusted by delnode 2, s=%d\n", w, w->state); 1068 w->state = w->state>=FWS_R ? FWS_U : FWS_INIT; 1069 } else { 1070 RT6_TRACE("W %p adjusted by delnode 2, s=%d\n", w, w->state); 1071 w->state = w->state>=FWS_C ? FWS_U : FWS_INIT; 1072 } 1073 } 1074 } 1075 } 1076 read_unlock(&fib6_walker_lock); 1077 1078 node_free(fn); 1079 if (pn->fn_flags&RTN_RTINFO || FIB6_SUBTREE(pn)) 1080 return pn; 1081 1082 rt6_release(pn->leaf); 1083 pn->leaf = NULL; 1084 fn = pn; 1085 } 1086 } 1087 1088 static void fib6_del_route(struct fib6_node *fn, struct rt6_info **rtp, 1089 struct nl_info *info) 1090 { 1091 struct fib6_walker_t *w; 1092 struct rt6_info *rt = *rtp; 1093 struct net *net = info->nl_net; 1094 1095 RT6_TRACE("fib6_del_route\n"); 1096 1097 /* Unlink it */ 1098 *rtp = rt->u.dst.rt6_next; 1099 rt->rt6i_node = NULL; 1100 net->ipv6.rt6_stats->fib_rt_entries--; 1101 net->ipv6.rt6_stats->fib_discarded_routes++; 1102 1103 /* Reset round-robin state, if necessary */ 1104 if (fn->rr_ptr == rt) 1105 fn->rr_ptr = NULL; 1106 1107 /* Adjust walkers */ 1108 read_lock(&fib6_walker_lock); 1109 FOR_WALKERS(w) { 1110 if (w->state == FWS_C && w->leaf == rt) { 1111 RT6_TRACE("walker %p adjusted by delroute\n", w); 1112 w->leaf = rt->u.dst.rt6_next; 1113 if (w->leaf == NULL) 1114 w->state = FWS_U; 1115 } 1116 } 1117 read_unlock(&fib6_walker_lock); 1118 1119 rt->u.dst.rt6_next = NULL; 1120 1121 /* If it was last route, expunge its radix tree node */ 1122 if (fn->leaf == NULL) { 1123 fn->fn_flags &= ~RTN_RTINFO; 1124 net->ipv6.rt6_stats->fib_route_nodes--; 1125 fn = fib6_repair_tree(net, fn); 1126 } 1127 1128 if (atomic_read(&rt->rt6i_ref) != 1) { 1129 /* This route is used as dummy address holder in some split 1130 * nodes. It is not leaked, but it still holds other resources, 1131 * which must be released in time. So, scan ascendant nodes 1132 * and replace dummy references to this route with references 1133 * to still alive ones. 1134 */ 1135 while (fn) { 1136 if (!(fn->fn_flags&RTN_RTINFO) && fn->leaf == rt) { 1137 fn->leaf = fib6_find_prefix(net, fn); 1138 atomic_inc(&fn->leaf->rt6i_ref); 1139 rt6_release(rt); 1140 } 1141 fn = fn->parent; 1142 } 1143 /* No more references are possible at this point. */ 1144 BUG_ON(atomic_read(&rt->rt6i_ref) != 1); 1145 } 1146 1147 inet6_rt_notify(RTM_DELROUTE, rt, info); 1148 rt6_release(rt); 1149 } 1150 1151 int fib6_del(struct rt6_info *rt, struct nl_info *info) 1152 { 1153 struct net *net = info->nl_net; 1154 struct fib6_node *fn = rt->rt6i_node; 1155 struct rt6_info **rtp; 1156 1157 #if RT6_DEBUG >= 2 1158 if (rt->u.dst.obsolete>0) { 1159 BUG_TRAP(fn==NULL); 1160 return -ENOENT; 1161 } 1162 #endif 1163 if (fn == NULL || rt == net->ipv6.ip6_null_entry) 1164 return -ENOENT; 1165 1166 BUG_TRAP(fn->fn_flags&RTN_RTINFO); 1167 1168 if (!(rt->rt6i_flags&RTF_CACHE)) { 1169 struct fib6_node *pn = fn; 1170 #ifdef CONFIG_IPV6_SUBTREES 1171 /* clones of this route might be in another subtree */ 1172 if (rt->rt6i_src.plen) { 1173 while (!(pn->fn_flags&RTN_ROOT)) 1174 pn = pn->parent; 1175 pn = pn->parent; 1176 } 1177 #endif 1178 fib6_prune_clones(info->nl_net, pn, rt); 1179 } 1180 1181 /* 1182 * Walk the leaf entries looking for ourself 1183 */ 1184 1185 for (rtp = &fn->leaf; *rtp; rtp = &(*rtp)->u.dst.rt6_next) { 1186 if (*rtp == rt) { 1187 fib6_del_route(fn, rtp, info); 1188 return 0; 1189 } 1190 } 1191 return -ENOENT; 1192 } 1193 1194 /* 1195 * Tree traversal function. 1196 * 1197 * Certainly, it is not interrupt safe. 1198 * However, it is internally reenterable wrt itself and fib6_add/fib6_del. 1199 * It means, that we can modify tree during walking 1200 * and use this function for garbage collection, clone pruning, 1201 * cleaning tree when a device goes down etc. etc. 1202 * 1203 * It guarantees that every node will be traversed, 1204 * and that it will be traversed only once. 1205 * 1206 * Callback function w->func may return: 1207 * 0 -> continue walking. 1208 * positive value -> walking is suspended (used by tree dumps, 1209 * and probably by gc, if it will be split to several slices) 1210 * negative value -> terminate walking. 1211 * 1212 * The function itself returns: 1213 * 0 -> walk is complete. 1214 * >0 -> walk is incomplete (i.e. suspended) 1215 * <0 -> walk is terminated by an error. 1216 */ 1217 1218 static int fib6_walk_continue(struct fib6_walker_t *w) 1219 { 1220 struct fib6_node *fn, *pn; 1221 1222 for (;;) { 1223 fn = w->node; 1224 if (fn == NULL) 1225 return 0; 1226 1227 if (w->prune && fn != w->root && 1228 fn->fn_flags&RTN_RTINFO && w->state < FWS_C) { 1229 w->state = FWS_C; 1230 w->leaf = fn->leaf; 1231 } 1232 switch (w->state) { 1233 #ifdef CONFIG_IPV6_SUBTREES 1234 case FWS_S: 1235 if (FIB6_SUBTREE(fn)) { 1236 w->node = FIB6_SUBTREE(fn); 1237 continue; 1238 } 1239 w->state = FWS_L; 1240 #endif 1241 case FWS_L: 1242 if (fn->left) { 1243 w->node = fn->left; 1244 w->state = FWS_INIT; 1245 continue; 1246 } 1247 w->state = FWS_R; 1248 case FWS_R: 1249 if (fn->right) { 1250 w->node = fn->right; 1251 w->state = FWS_INIT; 1252 continue; 1253 } 1254 w->state = FWS_C; 1255 w->leaf = fn->leaf; 1256 case FWS_C: 1257 if (w->leaf && fn->fn_flags&RTN_RTINFO) { 1258 int err = w->func(w); 1259 if (err) 1260 return err; 1261 continue; 1262 } 1263 w->state = FWS_U; 1264 case FWS_U: 1265 if (fn == w->root) 1266 return 0; 1267 pn = fn->parent; 1268 w->node = pn; 1269 #ifdef CONFIG_IPV6_SUBTREES 1270 if (FIB6_SUBTREE(pn) == fn) { 1271 BUG_TRAP(fn->fn_flags&RTN_ROOT); 1272 w->state = FWS_L; 1273 continue; 1274 } 1275 #endif 1276 if (pn->left == fn) { 1277 w->state = FWS_R; 1278 continue; 1279 } 1280 if (pn->right == fn) { 1281 w->state = FWS_C; 1282 w->leaf = w->node->leaf; 1283 continue; 1284 } 1285 #if RT6_DEBUG >= 2 1286 BUG_TRAP(0); 1287 #endif 1288 } 1289 } 1290 } 1291 1292 static int fib6_walk(struct fib6_walker_t *w) 1293 { 1294 int res; 1295 1296 w->state = FWS_INIT; 1297 w->node = w->root; 1298 1299 fib6_walker_link(w); 1300 res = fib6_walk_continue(w); 1301 if (res <= 0) 1302 fib6_walker_unlink(w); 1303 return res; 1304 } 1305 1306 static int fib6_clean_node(struct fib6_walker_t *w) 1307 { 1308 int res; 1309 struct rt6_info *rt; 1310 struct fib6_cleaner_t *c = container_of(w, struct fib6_cleaner_t, w); 1311 struct nl_info info = { 1312 .nl_net = c->net, 1313 }; 1314 1315 for (rt = w->leaf; rt; rt = rt->u.dst.rt6_next) { 1316 res = c->func(rt, c->arg); 1317 if (res < 0) { 1318 w->leaf = rt; 1319 res = fib6_del(rt, &info); 1320 if (res) { 1321 #if RT6_DEBUG >= 2 1322 printk(KERN_DEBUG "fib6_clean_node: del failed: rt=%p@%p err=%d\n", rt, rt->rt6i_node, res); 1323 #endif 1324 continue; 1325 } 1326 return 0; 1327 } 1328 BUG_TRAP(res==0); 1329 } 1330 w->leaf = rt; 1331 return 0; 1332 } 1333 1334 /* 1335 * Convenient frontend to tree walker. 1336 * 1337 * func is called on each route. 1338 * It may return -1 -> delete this route. 1339 * 0 -> continue walking 1340 * 1341 * prune==1 -> only immediate children of node (certainly, 1342 * ignoring pure split nodes) will be scanned. 1343 */ 1344 1345 static void fib6_clean_tree(struct net *net, struct fib6_node *root, 1346 int (*func)(struct rt6_info *, void *arg), 1347 int prune, void *arg) 1348 { 1349 struct fib6_cleaner_t c; 1350 1351 c.w.root = root; 1352 c.w.func = fib6_clean_node; 1353 c.w.prune = prune; 1354 c.func = func; 1355 c.arg = arg; 1356 c.net = net; 1357 1358 fib6_walk(&c.w); 1359 } 1360 1361 void fib6_clean_all(struct net *net, int (*func)(struct rt6_info *, void *arg), 1362 int prune, void *arg) 1363 { 1364 struct fib6_table *table; 1365 struct hlist_node *node; 1366 struct hlist_head *head; 1367 unsigned int h; 1368 1369 rcu_read_lock(); 1370 for (h = 0; h < FIB_TABLE_HASHSZ; h++) { 1371 head = &net->ipv6.fib_table_hash[h]; 1372 hlist_for_each_entry_rcu(table, node, head, tb6_hlist) { 1373 write_lock_bh(&table->tb6_lock); 1374 fib6_clean_tree(net, &table->tb6_root, 1375 func, prune, arg); 1376 write_unlock_bh(&table->tb6_lock); 1377 } 1378 } 1379 rcu_read_unlock(); 1380 } 1381 1382 static int fib6_prune_clone(struct rt6_info *rt, void *arg) 1383 { 1384 if (rt->rt6i_flags & RTF_CACHE) { 1385 RT6_TRACE("pruning clone %p\n", rt); 1386 return -1; 1387 } 1388 1389 return 0; 1390 } 1391 1392 static void fib6_prune_clones(struct net *net, struct fib6_node *fn, 1393 struct rt6_info *rt) 1394 { 1395 fib6_clean_tree(net, fn, fib6_prune_clone, 1, rt); 1396 } 1397 1398 /* 1399 * Garbage collection 1400 */ 1401 1402 static struct fib6_gc_args 1403 { 1404 int timeout; 1405 int more; 1406 } gc_args; 1407 1408 static int fib6_age(struct rt6_info *rt, void *arg) 1409 { 1410 unsigned long now = jiffies; 1411 1412 /* 1413 * check addrconf expiration here. 1414 * Routes are expired even if they are in use. 1415 * 1416 * Also age clones. Note, that clones are aged out 1417 * only if they are not in use now. 1418 */ 1419 1420 if (rt->rt6i_flags&RTF_EXPIRES && rt->rt6i_expires) { 1421 if (time_after(now, rt->rt6i_expires)) { 1422 RT6_TRACE("expiring %p\n", rt); 1423 return -1; 1424 } 1425 gc_args.more++; 1426 } else if (rt->rt6i_flags & RTF_CACHE) { 1427 if (atomic_read(&rt->u.dst.__refcnt) == 0 && 1428 time_after_eq(now, rt->u.dst.lastuse + gc_args.timeout)) { 1429 RT6_TRACE("aging clone %p\n", rt); 1430 return -1; 1431 } else if ((rt->rt6i_flags & RTF_GATEWAY) && 1432 (!(rt->rt6i_nexthop->flags & NTF_ROUTER))) { 1433 RT6_TRACE("purging route %p via non-router but gateway\n", 1434 rt); 1435 return -1; 1436 } 1437 gc_args.more++; 1438 } 1439 1440 return 0; 1441 } 1442 1443 static DEFINE_SPINLOCK(fib6_gc_lock); 1444 1445 void fib6_run_gc(unsigned long expires, struct net *net) 1446 { 1447 if (expires != ~0UL) { 1448 spin_lock_bh(&fib6_gc_lock); 1449 gc_args.timeout = expires ? (int)expires : 1450 net->ipv6.sysctl.ip6_rt_gc_interval; 1451 } else { 1452 local_bh_disable(); 1453 if (!spin_trylock(&fib6_gc_lock)) { 1454 mod_timer(net->ipv6.ip6_fib_timer, jiffies + HZ); 1455 local_bh_enable(); 1456 return; 1457 } 1458 gc_args.timeout = net->ipv6.sysctl.ip6_rt_gc_interval; 1459 } 1460 gc_args.more = 0; 1461 1462 icmp6_dst_gc(&gc_args.more); 1463 1464 fib6_clean_all(net, fib6_age, 0, NULL); 1465 1466 if (gc_args.more) 1467 mod_timer(net->ipv6.ip6_fib_timer, jiffies + 1468 net->ipv6.sysctl.ip6_rt_gc_interval); 1469 else { 1470 del_timer(net->ipv6.ip6_fib_timer); 1471 net->ipv6.ip6_fib_timer->expires = 0; 1472 } 1473 spin_unlock_bh(&fib6_gc_lock); 1474 } 1475 1476 static void fib6_gc_timer_cb(unsigned long arg) 1477 { 1478 fib6_run_gc(0, (struct net *)arg); 1479 } 1480 1481 static int fib6_net_init(struct net *net) 1482 { 1483 int ret; 1484 struct timer_list *timer; 1485 1486 ret = -ENOMEM; 1487 timer = kzalloc(sizeof(*timer), GFP_KERNEL); 1488 if (!timer) 1489 goto out; 1490 1491 setup_timer(timer, fib6_gc_timer_cb, (unsigned long)net); 1492 net->ipv6.ip6_fib_timer = timer; 1493 1494 net->ipv6.rt6_stats = kzalloc(sizeof(*net->ipv6.rt6_stats), GFP_KERNEL); 1495 if (!net->ipv6.rt6_stats) 1496 goto out_timer; 1497 1498 net->ipv6.fib_table_hash = 1499 kzalloc(sizeof(*net->ipv6.fib_table_hash)*FIB_TABLE_HASHSZ, 1500 GFP_KERNEL); 1501 if (!net->ipv6.fib_table_hash) 1502 goto out_rt6_stats; 1503 1504 net->ipv6.fib6_main_tbl = kzalloc(sizeof(*net->ipv6.fib6_main_tbl), 1505 GFP_KERNEL); 1506 if (!net->ipv6.fib6_main_tbl) 1507 goto out_fib_table_hash; 1508 1509 net->ipv6.fib6_main_tbl->tb6_id = RT6_TABLE_MAIN; 1510 net->ipv6.fib6_main_tbl->tb6_root.leaf = net->ipv6.ip6_null_entry; 1511 net->ipv6.fib6_main_tbl->tb6_root.fn_flags = 1512 RTN_ROOT | RTN_TL_ROOT | RTN_RTINFO; 1513 1514 #ifdef CONFIG_IPV6_MULTIPLE_TABLES 1515 net->ipv6.fib6_local_tbl = kzalloc(sizeof(*net->ipv6.fib6_local_tbl), 1516 GFP_KERNEL); 1517 if (!net->ipv6.fib6_local_tbl) 1518 goto out_fib6_main_tbl; 1519 net->ipv6.fib6_local_tbl->tb6_id = RT6_TABLE_LOCAL; 1520 net->ipv6.fib6_local_tbl->tb6_root.leaf = net->ipv6.ip6_null_entry; 1521 net->ipv6.fib6_local_tbl->tb6_root.fn_flags = 1522 RTN_ROOT | RTN_TL_ROOT | RTN_RTINFO; 1523 #endif 1524 fib6_tables_init(net); 1525 1526 ret = 0; 1527 out: 1528 return ret; 1529 1530 #ifdef CONFIG_IPV6_MULTIPLE_TABLES 1531 out_fib6_main_tbl: 1532 kfree(net->ipv6.fib6_main_tbl); 1533 #endif 1534 out_fib_table_hash: 1535 kfree(net->ipv6.fib_table_hash); 1536 out_rt6_stats: 1537 kfree(net->ipv6.rt6_stats); 1538 out_timer: 1539 kfree(timer); 1540 goto out; 1541 } 1542 1543 static void fib6_net_exit(struct net *net) 1544 { 1545 rt6_ifdown(net, NULL); 1546 del_timer(net->ipv6.ip6_fib_timer); 1547 kfree(net->ipv6.ip6_fib_timer); 1548 #ifdef CONFIG_IPV6_MULTIPLE_TABLES 1549 kfree(net->ipv6.fib6_local_tbl); 1550 #endif 1551 kfree(net->ipv6.fib6_main_tbl); 1552 kfree(net->ipv6.fib_table_hash); 1553 kfree(net->ipv6.rt6_stats); 1554 } 1555 1556 static struct pernet_operations fib6_net_ops = { 1557 .init = fib6_net_init, 1558 .exit = fib6_net_exit, 1559 }; 1560 1561 int __init fib6_init(void) 1562 { 1563 int ret = -ENOMEM; 1564 1565 fib6_node_kmem = kmem_cache_create("fib6_nodes", 1566 sizeof(struct fib6_node), 1567 0, SLAB_HWCACHE_ALIGN, 1568 NULL); 1569 if (!fib6_node_kmem) 1570 goto out; 1571 1572 ret = register_pernet_subsys(&fib6_net_ops); 1573 if (ret) 1574 goto out_kmem_cache_create; 1575 1576 ret = __rtnl_register(PF_INET6, RTM_GETROUTE, NULL, inet6_dump_fib); 1577 if (ret) 1578 goto out_unregister_subsys; 1579 out: 1580 return ret; 1581 1582 out_unregister_subsys: 1583 unregister_pernet_subsys(&fib6_net_ops); 1584 out_kmem_cache_create: 1585 kmem_cache_destroy(fib6_node_kmem); 1586 goto out; 1587 } 1588 1589 void fib6_gc_cleanup(void) 1590 { 1591 unregister_pernet_subsys(&fib6_net_ops); 1592 kmem_cache_destroy(fib6_node_kmem); 1593 } 1594