1 /* 2 * net/core/fib_rules.c Generic Routing Rules 3 * 4 * This program is free software; you can redistribute it and/or 5 * modify it under the terms of the GNU General Public License as 6 * published by the Free Software Foundation, version 2. 7 * 8 * Authors: Thomas Graf <tgraf@suug.ch> 9 */ 10 11 #include <linux/types.h> 12 #include <linux/kernel.h> 13 #include <linux/slab.h> 14 #include <linux/list.h> 15 #include <linux/module.h> 16 #include <net/net_namespace.h> 17 #include <net/sock.h> 18 #include <net/fib_rules.h> 19 20 int fib_default_rule_add(struct fib_rules_ops *ops, 21 u32 pref, u32 table, u32 flags) 22 { 23 struct fib_rule *r; 24 25 r = kzalloc(ops->rule_size, GFP_KERNEL); 26 if (r == NULL) 27 return -ENOMEM; 28 29 atomic_set(&r->refcnt, 1); 30 r->action = FR_ACT_TO_TBL; 31 r->pref = pref; 32 r->table = table; 33 r->flags = flags; 34 r->fr_net = hold_net(ops->fro_net); 35 36 /* The lock is not required here, the list in unreacheable 37 * at the moment this function is called */ 38 list_add_tail(&r->list, &ops->rules_list); 39 return 0; 40 } 41 EXPORT_SYMBOL(fib_default_rule_add); 42 43 u32 fib_default_rule_pref(struct fib_rules_ops *ops) 44 { 45 struct list_head *pos; 46 struct fib_rule *rule; 47 48 if (!list_empty(&ops->rules_list)) { 49 pos = ops->rules_list.next; 50 if (pos->next != &ops->rules_list) { 51 rule = list_entry(pos->next, struct fib_rule, list); 52 if (rule->pref) 53 return rule->pref - 1; 54 } 55 } 56 57 return 0; 58 } 59 EXPORT_SYMBOL(fib_default_rule_pref); 60 61 static void notify_rule_change(int event, struct fib_rule *rule, 62 struct fib_rules_ops *ops, struct nlmsghdr *nlh, 63 u32 pid); 64 65 static struct fib_rules_ops *lookup_rules_ops(struct net *net, int family) 66 { 67 struct fib_rules_ops *ops; 68 69 rcu_read_lock(); 70 list_for_each_entry_rcu(ops, &net->rules_ops, list) { 71 if (ops->family == family) { 72 if (!try_module_get(ops->owner)) 73 ops = NULL; 74 rcu_read_unlock(); 75 return ops; 76 } 77 } 78 rcu_read_unlock(); 79 80 return NULL; 81 } 82 83 static void rules_ops_put(struct fib_rules_ops *ops) 84 { 85 if (ops) 86 module_put(ops->owner); 87 } 88 89 static void flush_route_cache(struct fib_rules_ops *ops) 90 { 91 if (ops->flush_cache) 92 ops->flush_cache(ops); 93 } 94 95 static int __fib_rules_register(struct fib_rules_ops *ops) 96 { 97 int err = -EEXIST; 98 struct fib_rules_ops *o; 99 struct net *net; 100 101 net = ops->fro_net; 102 103 if (ops->rule_size < sizeof(struct fib_rule)) 104 return -EINVAL; 105 106 if (ops->match == NULL || ops->configure == NULL || 107 ops->compare == NULL || ops->fill == NULL || 108 ops->action == NULL) 109 return -EINVAL; 110 111 spin_lock(&net->rules_mod_lock); 112 list_for_each_entry(o, &net->rules_ops, list) 113 if (ops->family == o->family) 114 goto errout; 115 116 hold_net(net); 117 list_add_tail_rcu(&ops->list, &net->rules_ops); 118 err = 0; 119 errout: 120 spin_unlock(&net->rules_mod_lock); 121 122 return err; 123 } 124 125 struct fib_rules_ops * 126 fib_rules_register(const struct fib_rules_ops *tmpl, struct net *net) 127 { 128 struct fib_rules_ops *ops; 129 int err; 130 131 ops = kmemdup(tmpl, sizeof(*ops), GFP_KERNEL); 132 if (ops == NULL) 133 return ERR_PTR(-ENOMEM); 134 135 INIT_LIST_HEAD(&ops->rules_list); 136 ops->fro_net = net; 137 138 err = __fib_rules_register(ops); 139 if (err) { 140 kfree(ops); 141 ops = ERR_PTR(err); 142 } 143 144 return ops; 145 } 146 EXPORT_SYMBOL_GPL(fib_rules_register); 147 148 static void fib_rules_cleanup_ops(struct fib_rules_ops *ops) 149 { 150 struct fib_rule *rule, *tmp; 151 152 list_for_each_entry_safe(rule, tmp, &ops->rules_list, list) { 153 list_del_rcu(&rule->list); 154 if (ops->delete) 155 ops->delete(rule); 156 fib_rule_put(rule); 157 } 158 } 159 160 static void fib_rules_put_rcu(struct rcu_head *head) 161 { 162 struct fib_rules_ops *ops = container_of(head, struct fib_rules_ops, rcu); 163 struct net *net = ops->fro_net; 164 165 release_net(net); 166 kfree(ops); 167 } 168 169 void fib_rules_unregister(struct fib_rules_ops *ops) 170 { 171 struct net *net = ops->fro_net; 172 173 spin_lock(&net->rules_mod_lock); 174 list_del_rcu(&ops->list); 175 fib_rules_cleanup_ops(ops); 176 spin_unlock(&net->rules_mod_lock); 177 178 call_rcu(&ops->rcu, fib_rules_put_rcu); 179 } 180 EXPORT_SYMBOL_GPL(fib_rules_unregister); 181 182 static int fib_rule_match(struct fib_rule *rule, struct fib_rules_ops *ops, 183 struct flowi *fl, int flags) 184 { 185 int ret = 0; 186 187 if (rule->iifindex && (rule->iifindex != fl->flowi_iif)) 188 goto out; 189 190 if (rule->oifindex && (rule->oifindex != fl->flowi_oif)) 191 goto out; 192 193 if ((rule->mark ^ fl->flowi_mark) & rule->mark_mask) 194 goto out; 195 196 ret = ops->match(rule, fl, flags); 197 out: 198 return (rule->flags & FIB_RULE_INVERT) ? !ret : ret; 199 } 200 201 int fib_rules_lookup(struct fib_rules_ops *ops, struct flowi *fl, 202 int flags, struct fib_lookup_arg *arg) 203 { 204 struct fib_rule *rule; 205 int err; 206 207 rcu_read_lock(); 208 209 list_for_each_entry_rcu(rule, &ops->rules_list, list) { 210 jumped: 211 if (!fib_rule_match(rule, ops, fl, flags)) 212 continue; 213 214 if (rule->action == FR_ACT_GOTO) { 215 struct fib_rule *target; 216 217 target = rcu_dereference(rule->ctarget); 218 if (target == NULL) { 219 continue; 220 } else { 221 rule = target; 222 goto jumped; 223 } 224 } else if (rule->action == FR_ACT_NOP) 225 continue; 226 else 227 err = ops->action(rule, fl, flags, arg); 228 229 if (err != -EAGAIN) { 230 if ((arg->flags & FIB_LOOKUP_NOREF) || 231 likely(atomic_inc_not_zero(&rule->refcnt))) { 232 arg->rule = rule; 233 goto out; 234 } 235 break; 236 } 237 } 238 239 err = -ESRCH; 240 out: 241 rcu_read_unlock(); 242 243 return err; 244 } 245 EXPORT_SYMBOL_GPL(fib_rules_lookup); 246 247 static int validate_rulemsg(struct fib_rule_hdr *frh, struct nlattr **tb, 248 struct fib_rules_ops *ops) 249 { 250 int err = -EINVAL; 251 252 if (frh->src_len) 253 if (tb[FRA_SRC] == NULL || 254 frh->src_len > (ops->addr_size * 8) || 255 nla_len(tb[FRA_SRC]) != ops->addr_size) 256 goto errout; 257 258 if (frh->dst_len) 259 if (tb[FRA_DST] == NULL || 260 frh->dst_len > (ops->addr_size * 8) || 261 nla_len(tb[FRA_DST]) != ops->addr_size) 262 goto errout; 263 264 err = 0; 265 errout: 266 return err; 267 } 268 269 static int fib_nl_newrule(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg) 270 { 271 struct net *net = sock_net(skb->sk); 272 struct fib_rule_hdr *frh = nlmsg_data(nlh); 273 struct fib_rules_ops *ops = NULL; 274 struct fib_rule *rule, *r, *last = NULL; 275 struct nlattr *tb[FRA_MAX+1]; 276 int err = -EINVAL, unresolved = 0; 277 278 if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*frh))) 279 goto errout; 280 281 ops = lookup_rules_ops(net, frh->family); 282 if (ops == NULL) { 283 err = -EAFNOSUPPORT; 284 goto errout; 285 } 286 287 err = nlmsg_parse(nlh, sizeof(*frh), tb, FRA_MAX, ops->policy); 288 if (err < 0) 289 goto errout; 290 291 err = validate_rulemsg(frh, tb, ops); 292 if (err < 0) 293 goto errout; 294 295 rule = kzalloc(ops->rule_size, GFP_KERNEL); 296 if (rule == NULL) { 297 err = -ENOMEM; 298 goto errout; 299 } 300 rule->fr_net = hold_net(net); 301 302 if (tb[FRA_PRIORITY]) 303 rule->pref = nla_get_u32(tb[FRA_PRIORITY]); 304 305 if (tb[FRA_IIFNAME]) { 306 struct net_device *dev; 307 308 rule->iifindex = -1; 309 nla_strlcpy(rule->iifname, tb[FRA_IIFNAME], IFNAMSIZ); 310 dev = __dev_get_by_name(net, rule->iifname); 311 if (dev) 312 rule->iifindex = dev->ifindex; 313 } 314 315 if (tb[FRA_OIFNAME]) { 316 struct net_device *dev; 317 318 rule->oifindex = -1; 319 nla_strlcpy(rule->oifname, tb[FRA_OIFNAME], IFNAMSIZ); 320 dev = __dev_get_by_name(net, rule->oifname); 321 if (dev) 322 rule->oifindex = dev->ifindex; 323 } 324 325 if (tb[FRA_FWMARK]) { 326 rule->mark = nla_get_u32(tb[FRA_FWMARK]); 327 if (rule->mark) 328 /* compatibility: if the mark value is non-zero all bits 329 * are compared unless a mask is explicitly specified. 330 */ 331 rule->mark_mask = 0xFFFFFFFF; 332 } 333 334 if (tb[FRA_FWMASK]) 335 rule->mark_mask = nla_get_u32(tb[FRA_FWMASK]); 336 337 rule->action = frh->action; 338 rule->flags = frh->flags; 339 rule->table = frh_get_table(frh, tb); 340 341 if (!tb[FRA_PRIORITY] && ops->default_pref) 342 rule->pref = ops->default_pref(ops); 343 344 err = -EINVAL; 345 if (tb[FRA_GOTO]) { 346 if (rule->action != FR_ACT_GOTO) 347 goto errout_free; 348 349 rule->target = nla_get_u32(tb[FRA_GOTO]); 350 /* Backward jumps are prohibited to avoid endless loops */ 351 if (rule->target <= rule->pref) 352 goto errout_free; 353 354 list_for_each_entry(r, &ops->rules_list, list) { 355 if (r->pref == rule->target) { 356 RCU_INIT_POINTER(rule->ctarget, r); 357 break; 358 } 359 } 360 361 if (rcu_dereference_protected(rule->ctarget, 1) == NULL) 362 unresolved = 1; 363 } else if (rule->action == FR_ACT_GOTO) 364 goto errout_free; 365 366 err = ops->configure(rule, skb, frh, tb); 367 if (err < 0) 368 goto errout_free; 369 370 list_for_each_entry(r, &ops->rules_list, list) { 371 if (r->pref > rule->pref) 372 break; 373 last = r; 374 } 375 376 fib_rule_get(rule); 377 378 if (last) 379 list_add_rcu(&rule->list, &last->list); 380 else 381 list_add_rcu(&rule->list, &ops->rules_list); 382 383 if (ops->unresolved_rules) { 384 /* 385 * There are unresolved goto rules in the list, check if 386 * any of them are pointing to this new rule. 387 */ 388 list_for_each_entry(r, &ops->rules_list, list) { 389 if (r->action == FR_ACT_GOTO && 390 r->target == rule->pref && 391 rtnl_dereference(r->ctarget) == NULL) { 392 rcu_assign_pointer(r->ctarget, rule); 393 if (--ops->unresolved_rules == 0) 394 break; 395 } 396 } 397 } 398 399 if (rule->action == FR_ACT_GOTO) 400 ops->nr_goto_rules++; 401 402 if (unresolved) 403 ops->unresolved_rules++; 404 405 notify_rule_change(RTM_NEWRULE, rule, ops, nlh, NETLINK_CB(skb).portid); 406 flush_route_cache(ops); 407 rules_ops_put(ops); 408 return 0; 409 410 errout_free: 411 release_net(rule->fr_net); 412 kfree(rule); 413 errout: 414 rules_ops_put(ops); 415 return err; 416 } 417 418 static int fib_nl_delrule(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg) 419 { 420 struct net *net = sock_net(skb->sk); 421 struct fib_rule_hdr *frh = nlmsg_data(nlh); 422 struct fib_rules_ops *ops = NULL; 423 struct fib_rule *rule, *tmp; 424 struct nlattr *tb[FRA_MAX+1]; 425 int err = -EINVAL; 426 427 if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*frh))) 428 goto errout; 429 430 ops = lookup_rules_ops(net, frh->family); 431 if (ops == NULL) { 432 err = -EAFNOSUPPORT; 433 goto errout; 434 } 435 436 err = nlmsg_parse(nlh, sizeof(*frh), tb, FRA_MAX, ops->policy); 437 if (err < 0) 438 goto errout; 439 440 err = validate_rulemsg(frh, tb, ops); 441 if (err < 0) 442 goto errout; 443 444 list_for_each_entry(rule, &ops->rules_list, list) { 445 if (frh->action && (frh->action != rule->action)) 446 continue; 447 448 if (frh->table && (frh_get_table(frh, tb) != rule->table)) 449 continue; 450 451 if (tb[FRA_PRIORITY] && 452 (rule->pref != nla_get_u32(tb[FRA_PRIORITY]))) 453 continue; 454 455 if (tb[FRA_IIFNAME] && 456 nla_strcmp(tb[FRA_IIFNAME], rule->iifname)) 457 continue; 458 459 if (tb[FRA_OIFNAME] && 460 nla_strcmp(tb[FRA_OIFNAME], rule->oifname)) 461 continue; 462 463 if (tb[FRA_FWMARK] && 464 (rule->mark != nla_get_u32(tb[FRA_FWMARK]))) 465 continue; 466 467 if (tb[FRA_FWMASK] && 468 (rule->mark_mask != nla_get_u32(tb[FRA_FWMASK]))) 469 continue; 470 471 if (!ops->compare(rule, frh, tb)) 472 continue; 473 474 if (rule->flags & FIB_RULE_PERMANENT) { 475 err = -EPERM; 476 goto errout; 477 } 478 479 list_del_rcu(&rule->list); 480 481 if (rule->action == FR_ACT_GOTO) { 482 ops->nr_goto_rules--; 483 if (rtnl_dereference(rule->ctarget) == NULL) 484 ops->unresolved_rules--; 485 } 486 487 /* 488 * Check if this rule is a target to any of them. If so, 489 * disable them. As this operation is eventually very 490 * expensive, it is only performed if goto rules have 491 * actually been added. 492 */ 493 if (ops->nr_goto_rules > 0) { 494 list_for_each_entry(tmp, &ops->rules_list, list) { 495 if (rtnl_dereference(tmp->ctarget) == rule) { 496 RCU_INIT_POINTER(tmp->ctarget, NULL); 497 ops->unresolved_rules++; 498 } 499 } 500 } 501 502 notify_rule_change(RTM_DELRULE, rule, ops, nlh, 503 NETLINK_CB(skb).portid); 504 if (ops->delete) 505 ops->delete(rule); 506 fib_rule_put(rule); 507 flush_route_cache(ops); 508 rules_ops_put(ops); 509 return 0; 510 } 511 512 err = -ENOENT; 513 errout: 514 rules_ops_put(ops); 515 return err; 516 } 517 518 static inline size_t fib_rule_nlmsg_size(struct fib_rules_ops *ops, 519 struct fib_rule *rule) 520 { 521 size_t payload = NLMSG_ALIGN(sizeof(struct fib_rule_hdr)) 522 + nla_total_size(IFNAMSIZ) /* FRA_IIFNAME */ 523 + nla_total_size(IFNAMSIZ) /* FRA_OIFNAME */ 524 + nla_total_size(4) /* FRA_PRIORITY */ 525 + nla_total_size(4) /* FRA_TABLE */ 526 + nla_total_size(4) /* FRA_FWMARK */ 527 + nla_total_size(4); /* FRA_FWMASK */ 528 529 if (ops->nlmsg_payload) 530 payload += ops->nlmsg_payload(rule); 531 532 return payload; 533 } 534 535 static int fib_nl_fill_rule(struct sk_buff *skb, struct fib_rule *rule, 536 u32 pid, u32 seq, int type, int flags, 537 struct fib_rules_ops *ops) 538 { 539 struct nlmsghdr *nlh; 540 struct fib_rule_hdr *frh; 541 542 nlh = nlmsg_put(skb, pid, seq, type, sizeof(*frh), flags); 543 if (nlh == NULL) 544 return -EMSGSIZE; 545 546 frh = nlmsg_data(nlh); 547 frh->family = ops->family; 548 frh->table = rule->table; 549 if (nla_put_u32(skb, FRA_TABLE, rule->table)) 550 goto nla_put_failure; 551 frh->res1 = 0; 552 frh->res2 = 0; 553 frh->action = rule->action; 554 frh->flags = rule->flags; 555 556 if (rule->action == FR_ACT_GOTO && 557 rcu_access_pointer(rule->ctarget) == NULL) 558 frh->flags |= FIB_RULE_UNRESOLVED; 559 560 if (rule->iifname[0]) { 561 if (nla_put_string(skb, FRA_IIFNAME, rule->iifname)) 562 goto nla_put_failure; 563 if (rule->iifindex == -1) 564 frh->flags |= FIB_RULE_IIF_DETACHED; 565 } 566 567 if (rule->oifname[0]) { 568 if (nla_put_string(skb, FRA_OIFNAME, rule->oifname)) 569 goto nla_put_failure; 570 if (rule->oifindex == -1) 571 frh->flags |= FIB_RULE_OIF_DETACHED; 572 } 573 574 if ((rule->pref && 575 nla_put_u32(skb, FRA_PRIORITY, rule->pref)) || 576 (rule->mark && 577 nla_put_u32(skb, FRA_FWMARK, rule->mark)) || 578 ((rule->mark_mask || rule->mark) && 579 nla_put_u32(skb, FRA_FWMASK, rule->mark_mask)) || 580 (rule->target && 581 nla_put_u32(skb, FRA_GOTO, rule->target))) 582 goto nla_put_failure; 583 if (ops->fill(rule, skb, frh) < 0) 584 goto nla_put_failure; 585 586 return nlmsg_end(skb, nlh); 587 588 nla_put_failure: 589 nlmsg_cancel(skb, nlh); 590 return -EMSGSIZE; 591 } 592 593 static int dump_rules(struct sk_buff *skb, struct netlink_callback *cb, 594 struct fib_rules_ops *ops) 595 { 596 int idx = 0; 597 struct fib_rule *rule; 598 599 rcu_read_lock(); 600 list_for_each_entry_rcu(rule, &ops->rules_list, list) { 601 if (idx < cb->args[1]) 602 goto skip; 603 604 if (fib_nl_fill_rule(skb, rule, NETLINK_CB(cb->skb).portid, 605 cb->nlh->nlmsg_seq, RTM_NEWRULE, 606 NLM_F_MULTI, ops) < 0) 607 break; 608 skip: 609 idx++; 610 } 611 rcu_read_unlock(); 612 cb->args[1] = idx; 613 rules_ops_put(ops); 614 615 return skb->len; 616 } 617 618 static int fib_nl_dumprule(struct sk_buff *skb, struct netlink_callback *cb) 619 { 620 struct net *net = sock_net(skb->sk); 621 struct fib_rules_ops *ops; 622 int idx = 0, family; 623 624 family = rtnl_msg_family(cb->nlh); 625 if (family != AF_UNSPEC) { 626 /* Protocol specific dump request */ 627 ops = lookup_rules_ops(net, family); 628 if (ops == NULL) 629 return -EAFNOSUPPORT; 630 631 return dump_rules(skb, cb, ops); 632 } 633 634 rcu_read_lock(); 635 list_for_each_entry_rcu(ops, &net->rules_ops, list) { 636 if (idx < cb->args[0] || !try_module_get(ops->owner)) 637 goto skip; 638 639 if (dump_rules(skb, cb, ops) < 0) 640 break; 641 642 cb->args[1] = 0; 643 skip: 644 idx++; 645 } 646 rcu_read_unlock(); 647 cb->args[0] = idx; 648 649 return skb->len; 650 } 651 652 static void notify_rule_change(int event, struct fib_rule *rule, 653 struct fib_rules_ops *ops, struct nlmsghdr *nlh, 654 u32 pid) 655 { 656 struct net *net; 657 struct sk_buff *skb; 658 int err = -ENOBUFS; 659 660 net = ops->fro_net; 661 skb = nlmsg_new(fib_rule_nlmsg_size(ops, rule), GFP_KERNEL); 662 if (skb == NULL) 663 goto errout; 664 665 err = fib_nl_fill_rule(skb, rule, pid, nlh->nlmsg_seq, event, 0, ops); 666 if (err < 0) { 667 /* -EMSGSIZE implies BUG in fib_rule_nlmsg_size() */ 668 WARN_ON(err == -EMSGSIZE); 669 kfree_skb(skb); 670 goto errout; 671 } 672 673 rtnl_notify(skb, net, pid, ops->nlgroup, nlh, GFP_KERNEL); 674 return; 675 errout: 676 if (err < 0) 677 rtnl_set_sk_err(net, ops->nlgroup, err); 678 } 679 680 static void attach_rules(struct list_head *rules, struct net_device *dev) 681 { 682 struct fib_rule *rule; 683 684 list_for_each_entry(rule, rules, list) { 685 if (rule->iifindex == -1 && 686 strcmp(dev->name, rule->iifname) == 0) 687 rule->iifindex = dev->ifindex; 688 if (rule->oifindex == -1 && 689 strcmp(dev->name, rule->oifname) == 0) 690 rule->oifindex = dev->ifindex; 691 } 692 } 693 694 static void detach_rules(struct list_head *rules, struct net_device *dev) 695 { 696 struct fib_rule *rule; 697 698 list_for_each_entry(rule, rules, list) { 699 if (rule->iifindex == dev->ifindex) 700 rule->iifindex = -1; 701 if (rule->oifindex == dev->ifindex) 702 rule->oifindex = -1; 703 } 704 } 705 706 707 static int fib_rules_event(struct notifier_block *this, unsigned long event, 708 void *ptr) 709 { 710 struct net_device *dev = ptr; 711 struct net *net = dev_net(dev); 712 struct fib_rules_ops *ops; 713 714 ASSERT_RTNL(); 715 716 switch (event) { 717 case NETDEV_REGISTER: 718 list_for_each_entry(ops, &net->rules_ops, list) 719 attach_rules(&ops->rules_list, dev); 720 break; 721 722 case NETDEV_UNREGISTER: 723 list_for_each_entry(ops, &net->rules_ops, list) 724 detach_rules(&ops->rules_list, dev); 725 break; 726 } 727 728 return NOTIFY_DONE; 729 } 730 731 static struct notifier_block fib_rules_notifier = { 732 .notifier_call = fib_rules_event, 733 }; 734 735 static int __net_init fib_rules_net_init(struct net *net) 736 { 737 INIT_LIST_HEAD(&net->rules_ops); 738 spin_lock_init(&net->rules_mod_lock); 739 return 0; 740 } 741 742 static struct pernet_operations fib_rules_net_ops = { 743 .init = fib_rules_net_init, 744 }; 745 746 static int __init fib_rules_init(void) 747 { 748 int err; 749 rtnl_register(PF_UNSPEC, RTM_NEWRULE, fib_nl_newrule, NULL, NULL); 750 rtnl_register(PF_UNSPEC, RTM_DELRULE, fib_nl_delrule, NULL, NULL); 751 rtnl_register(PF_UNSPEC, RTM_GETRULE, NULL, fib_nl_dumprule, NULL); 752 753 err = register_pernet_subsys(&fib_rules_net_ops); 754 if (err < 0) 755 goto fail; 756 757 err = register_netdevice_notifier(&fib_rules_notifier); 758 if (err < 0) 759 goto fail_unregister; 760 761 return 0; 762 763 fail_unregister: 764 unregister_pernet_subsys(&fib_rules_net_ops); 765 fail: 766 rtnl_unregister(PF_UNSPEC, RTM_NEWRULE); 767 rtnl_unregister(PF_UNSPEC, RTM_DELRULE); 768 rtnl_unregister(PF_UNSPEC, RTM_GETRULE); 769 return err; 770 } 771 772 subsys_initcall(fib_rules_init); 773