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 #include <net/ip_tunnels.h> 20 21 int fib_default_rule_add(struct fib_rules_ops *ops, 22 u32 pref, u32 table, u32 flags) 23 { 24 struct fib_rule *r; 25 26 r = kzalloc(ops->rule_size, GFP_KERNEL); 27 if (r == NULL) 28 return -ENOMEM; 29 30 atomic_set(&r->refcnt, 1); 31 r->action = FR_ACT_TO_TBL; 32 r->pref = pref; 33 r->table = table; 34 r->flags = flags; 35 r->fr_net = ops->fro_net; 36 37 r->suppress_prefixlen = -1; 38 r->suppress_ifgroup = -1; 39 40 /* The lock is not required here, the list in unreacheable 41 * at the moment this function is called */ 42 list_add_tail(&r->list, &ops->rules_list); 43 return 0; 44 } 45 EXPORT_SYMBOL(fib_default_rule_add); 46 47 static u32 fib_default_rule_pref(struct fib_rules_ops *ops) 48 { 49 struct list_head *pos; 50 struct fib_rule *rule; 51 52 if (!list_empty(&ops->rules_list)) { 53 pos = ops->rules_list.next; 54 if (pos->next != &ops->rules_list) { 55 rule = list_entry(pos->next, struct fib_rule, list); 56 if (rule->pref) 57 return rule->pref - 1; 58 } 59 } 60 61 return 0; 62 } 63 64 static void notify_rule_change(int event, struct fib_rule *rule, 65 struct fib_rules_ops *ops, struct nlmsghdr *nlh, 66 u32 pid); 67 68 static struct fib_rules_ops *lookup_rules_ops(struct net *net, int family) 69 { 70 struct fib_rules_ops *ops; 71 72 rcu_read_lock(); 73 list_for_each_entry_rcu(ops, &net->rules_ops, list) { 74 if (ops->family == family) { 75 if (!try_module_get(ops->owner)) 76 ops = NULL; 77 rcu_read_unlock(); 78 return ops; 79 } 80 } 81 rcu_read_unlock(); 82 83 return NULL; 84 } 85 86 static void rules_ops_put(struct fib_rules_ops *ops) 87 { 88 if (ops) 89 module_put(ops->owner); 90 } 91 92 static void flush_route_cache(struct fib_rules_ops *ops) 93 { 94 if (ops->flush_cache) 95 ops->flush_cache(ops); 96 } 97 98 static int __fib_rules_register(struct fib_rules_ops *ops) 99 { 100 int err = -EEXIST; 101 struct fib_rules_ops *o; 102 struct net *net; 103 104 net = ops->fro_net; 105 106 if (ops->rule_size < sizeof(struct fib_rule)) 107 return -EINVAL; 108 109 if (ops->match == NULL || ops->configure == NULL || 110 ops->compare == NULL || ops->fill == NULL || 111 ops->action == NULL) 112 return -EINVAL; 113 114 spin_lock(&net->rules_mod_lock); 115 list_for_each_entry(o, &net->rules_ops, list) 116 if (ops->family == o->family) 117 goto errout; 118 119 list_add_tail_rcu(&ops->list, &net->rules_ops); 120 err = 0; 121 errout: 122 spin_unlock(&net->rules_mod_lock); 123 124 return err; 125 } 126 127 struct fib_rules_ops * 128 fib_rules_register(const struct fib_rules_ops *tmpl, struct net *net) 129 { 130 struct fib_rules_ops *ops; 131 int err; 132 133 ops = kmemdup(tmpl, sizeof(*ops), GFP_KERNEL); 134 if (ops == NULL) 135 return ERR_PTR(-ENOMEM); 136 137 INIT_LIST_HEAD(&ops->rules_list); 138 ops->fro_net = net; 139 140 err = __fib_rules_register(ops); 141 if (err) { 142 kfree(ops); 143 ops = ERR_PTR(err); 144 } 145 146 return ops; 147 } 148 EXPORT_SYMBOL_GPL(fib_rules_register); 149 150 static void fib_rules_cleanup_ops(struct fib_rules_ops *ops) 151 { 152 struct fib_rule *rule, *tmp; 153 154 list_for_each_entry_safe(rule, tmp, &ops->rules_list, list) { 155 list_del_rcu(&rule->list); 156 if (ops->delete) 157 ops->delete(rule); 158 fib_rule_put(rule); 159 } 160 } 161 162 void fib_rules_unregister(struct fib_rules_ops *ops) 163 { 164 struct net *net = ops->fro_net; 165 166 spin_lock(&net->rules_mod_lock); 167 list_del_rcu(&ops->list); 168 spin_unlock(&net->rules_mod_lock); 169 170 fib_rules_cleanup_ops(ops); 171 kfree_rcu(ops, rcu); 172 } 173 EXPORT_SYMBOL_GPL(fib_rules_unregister); 174 175 static int fib_rule_match(struct fib_rule *rule, struct fib_rules_ops *ops, 176 struct flowi *fl, int flags, 177 struct fib_lookup_arg *arg) 178 { 179 int ret = 0; 180 181 if (rule->iifindex && (rule->iifindex != fl->flowi_iif)) 182 goto out; 183 184 if (rule->oifindex && (rule->oifindex != fl->flowi_oif)) 185 goto out; 186 187 if ((rule->mark ^ fl->flowi_mark) & rule->mark_mask) 188 goto out; 189 190 if (rule->tun_id && (rule->tun_id != fl->flowi_tun_key.tun_id)) 191 goto out; 192 193 if (rule->l3mdev && !l3mdev_fib_rule_match(rule->fr_net, fl, arg)) 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, arg)) 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 && ops->suppress && ops->suppress(rule, arg)) 230 continue; 231 232 if (err != -EAGAIN) { 233 if ((arg->flags & FIB_LOOKUP_NOREF) || 234 likely(atomic_inc_not_zero(&rule->refcnt))) { 235 arg->rule = rule; 236 goto out; 237 } 238 break; 239 } 240 } 241 242 err = -ESRCH; 243 out: 244 rcu_read_unlock(); 245 246 return err; 247 } 248 EXPORT_SYMBOL_GPL(fib_rules_lookup); 249 250 static int validate_rulemsg(struct fib_rule_hdr *frh, struct nlattr **tb, 251 struct fib_rules_ops *ops) 252 { 253 int err = -EINVAL; 254 255 if (frh->src_len) 256 if (tb[FRA_SRC] == NULL || 257 frh->src_len > (ops->addr_size * 8) || 258 nla_len(tb[FRA_SRC]) != ops->addr_size) 259 goto errout; 260 261 if (frh->dst_len) 262 if (tb[FRA_DST] == NULL || 263 frh->dst_len > (ops->addr_size * 8) || 264 nla_len(tb[FRA_DST]) != ops->addr_size) 265 goto errout; 266 267 err = 0; 268 errout: 269 return err; 270 } 271 272 int fib_nl_newrule(struct sk_buff *skb, struct nlmsghdr *nlh) 273 { 274 struct net *net = sock_net(skb->sk); 275 struct fib_rule_hdr *frh = nlmsg_data(nlh); 276 struct fib_rules_ops *ops = NULL; 277 struct fib_rule *rule, *r, *last = NULL; 278 struct nlattr *tb[FRA_MAX+1]; 279 int err = -EINVAL, unresolved = 0; 280 281 if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*frh))) 282 goto errout; 283 284 ops = lookup_rules_ops(net, frh->family); 285 if (ops == NULL) { 286 err = -EAFNOSUPPORT; 287 goto errout; 288 } 289 290 err = nlmsg_parse(nlh, sizeof(*frh), tb, FRA_MAX, ops->policy); 291 if (err < 0) 292 goto errout; 293 294 err = validate_rulemsg(frh, tb, ops); 295 if (err < 0) 296 goto errout; 297 298 rule = kzalloc(ops->rule_size, GFP_KERNEL); 299 if (rule == NULL) { 300 err = -ENOMEM; 301 goto errout; 302 } 303 rule->fr_net = net; 304 305 rule->pref = tb[FRA_PRIORITY] ? nla_get_u32(tb[FRA_PRIORITY]) 306 : fib_default_rule_pref(ops); 307 308 if (tb[FRA_IIFNAME]) { 309 struct net_device *dev; 310 311 rule->iifindex = -1; 312 nla_strlcpy(rule->iifname, tb[FRA_IIFNAME], IFNAMSIZ); 313 dev = __dev_get_by_name(net, rule->iifname); 314 if (dev) 315 rule->iifindex = dev->ifindex; 316 } 317 318 if (tb[FRA_OIFNAME]) { 319 struct net_device *dev; 320 321 rule->oifindex = -1; 322 nla_strlcpy(rule->oifname, tb[FRA_OIFNAME], IFNAMSIZ); 323 dev = __dev_get_by_name(net, rule->oifname); 324 if (dev) 325 rule->oifindex = dev->ifindex; 326 } 327 328 if (tb[FRA_FWMARK]) { 329 rule->mark = nla_get_u32(tb[FRA_FWMARK]); 330 if (rule->mark) 331 /* compatibility: if the mark value is non-zero all bits 332 * are compared unless a mask is explicitly specified. 333 */ 334 rule->mark_mask = 0xFFFFFFFF; 335 } 336 337 if (tb[FRA_FWMASK]) 338 rule->mark_mask = nla_get_u32(tb[FRA_FWMASK]); 339 340 if (tb[FRA_TUN_ID]) 341 rule->tun_id = nla_get_be64(tb[FRA_TUN_ID]); 342 343 if (tb[FRA_L3MDEV]) { 344 #ifdef CONFIG_NET_L3_MASTER_DEV 345 rule->l3mdev = nla_get_u8(tb[FRA_L3MDEV]); 346 if (rule->l3mdev != 1) 347 #endif 348 goto errout_free; 349 } 350 351 rule->action = frh->action; 352 rule->flags = frh->flags; 353 rule->table = frh_get_table(frh, tb); 354 if (tb[FRA_SUPPRESS_PREFIXLEN]) 355 rule->suppress_prefixlen = nla_get_u32(tb[FRA_SUPPRESS_PREFIXLEN]); 356 else 357 rule->suppress_prefixlen = -1; 358 359 if (tb[FRA_SUPPRESS_IFGROUP]) 360 rule->suppress_ifgroup = nla_get_u32(tb[FRA_SUPPRESS_IFGROUP]); 361 else 362 rule->suppress_ifgroup = -1; 363 364 err = -EINVAL; 365 if (tb[FRA_GOTO]) { 366 if (rule->action != FR_ACT_GOTO) 367 goto errout_free; 368 369 rule->target = nla_get_u32(tb[FRA_GOTO]); 370 /* Backward jumps are prohibited to avoid endless loops */ 371 if (rule->target <= rule->pref) 372 goto errout_free; 373 374 list_for_each_entry(r, &ops->rules_list, list) { 375 if (r->pref == rule->target) { 376 RCU_INIT_POINTER(rule->ctarget, r); 377 break; 378 } 379 } 380 381 if (rcu_dereference_protected(rule->ctarget, 1) == NULL) 382 unresolved = 1; 383 } else if (rule->action == FR_ACT_GOTO) 384 goto errout_free; 385 386 if (rule->l3mdev && rule->table) 387 goto errout_free; 388 389 err = ops->configure(rule, skb, frh, tb); 390 if (err < 0) 391 goto errout_free; 392 393 list_for_each_entry(r, &ops->rules_list, list) { 394 if (r->pref > rule->pref) 395 break; 396 last = r; 397 } 398 399 fib_rule_get(rule); 400 401 if (last) 402 list_add_rcu(&rule->list, &last->list); 403 else 404 list_add_rcu(&rule->list, &ops->rules_list); 405 406 if (ops->unresolved_rules) { 407 /* 408 * There are unresolved goto rules in the list, check if 409 * any of them are pointing to this new rule. 410 */ 411 list_for_each_entry(r, &ops->rules_list, list) { 412 if (r->action == FR_ACT_GOTO && 413 r->target == rule->pref && 414 rtnl_dereference(r->ctarget) == NULL) { 415 rcu_assign_pointer(r->ctarget, rule); 416 if (--ops->unresolved_rules == 0) 417 break; 418 } 419 } 420 } 421 422 if (rule->action == FR_ACT_GOTO) 423 ops->nr_goto_rules++; 424 425 if (unresolved) 426 ops->unresolved_rules++; 427 428 if (rule->tun_id) 429 ip_tunnel_need_metadata(); 430 431 notify_rule_change(RTM_NEWRULE, rule, ops, nlh, NETLINK_CB(skb).portid); 432 flush_route_cache(ops); 433 rules_ops_put(ops); 434 return 0; 435 436 errout_free: 437 kfree(rule); 438 errout: 439 rules_ops_put(ops); 440 return err; 441 } 442 EXPORT_SYMBOL_GPL(fib_nl_newrule); 443 444 int fib_nl_delrule(struct sk_buff *skb, struct nlmsghdr *nlh) 445 { 446 struct net *net = sock_net(skb->sk); 447 struct fib_rule_hdr *frh = nlmsg_data(nlh); 448 struct fib_rules_ops *ops = NULL; 449 struct fib_rule *rule, *tmp; 450 struct nlattr *tb[FRA_MAX+1]; 451 int err = -EINVAL; 452 453 if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*frh))) 454 goto errout; 455 456 ops = lookup_rules_ops(net, frh->family); 457 if (ops == NULL) { 458 err = -EAFNOSUPPORT; 459 goto errout; 460 } 461 462 err = nlmsg_parse(nlh, sizeof(*frh), tb, FRA_MAX, ops->policy); 463 if (err < 0) 464 goto errout; 465 466 err = validate_rulemsg(frh, tb, ops); 467 if (err < 0) 468 goto errout; 469 470 list_for_each_entry(rule, &ops->rules_list, list) { 471 if (frh->action && (frh->action != rule->action)) 472 continue; 473 474 if (frh_get_table(frh, tb) && 475 (frh_get_table(frh, tb) != rule->table)) 476 continue; 477 478 if (tb[FRA_PRIORITY] && 479 (rule->pref != nla_get_u32(tb[FRA_PRIORITY]))) 480 continue; 481 482 if (tb[FRA_IIFNAME] && 483 nla_strcmp(tb[FRA_IIFNAME], rule->iifname)) 484 continue; 485 486 if (tb[FRA_OIFNAME] && 487 nla_strcmp(tb[FRA_OIFNAME], rule->oifname)) 488 continue; 489 490 if (tb[FRA_FWMARK] && 491 (rule->mark != nla_get_u32(tb[FRA_FWMARK]))) 492 continue; 493 494 if (tb[FRA_FWMASK] && 495 (rule->mark_mask != nla_get_u32(tb[FRA_FWMASK]))) 496 continue; 497 498 if (tb[FRA_TUN_ID] && 499 (rule->tun_id != nla_get_be64(tb[FRA_TUN_ID]))) 500 continue; 501 502 if (tb[FRA_L3MDEV] && 503 (rule->l3mdev != nla_get_u8(tb[FRA_L3MDEV]))) 504 continue; 505 506 if (!ops->compare(rule, frh, tb)) 507 continue; 508 509 if (rule->flags & FIB_RULE_PERMANENT) { 510 err = -EPERM; 511 goto errout; 512 } 513 514 if (ops->delete) { 515 err = ops->delete(rule); 516 if (err) 517 goto errout; 518 } 519 520 if (rule->tun_id) 521 ip_tunnel_unneed_metadata(); 522 523 list_del_rcu(&rule->list); 524 525 if (rule->action == FR_ACT_GOTO) { 526 ops->nr_goto_rules--; 527 if (rtnl_dereference(rule->ctarget) == NULL) 528 ops->unresolved_rules--; 529 } 530 531 /* 532 * Check if this rule is a target to any of them. If so, 533 * disable them. As this operation is eventually very 534 * expensive, it is only performed if goto rules have 535 * actually been added. 536 */ 537 if (ops->nr_goto_rules > 0) { 538 list_for_each_entry(tmp, &ops->rules_list, list) { 539 if (rtnl_dereference(tmp->ctarget) == rule) { 540 RCU_INIT_POINTER(tmp->ctarget, NULL); 541 ops->unresolved_rules++; 542 } 543 } 544 } 545 546 notify_rule_change(RTM_DELRULE, rule, ops, nlh, 547 NETLINK_CB(skb).portid); 548 fib_rule_put(rule); 549 flush_route_cache(ops); 550 rules_ops_put(ops); 551 return 0; 552 } 553 554 err = -ENOENT; 555 errout: 556 rules_ops_put(ops); 557 return err; 558 } 559 EXPORT_SYMBOL_GPL(fib_nl_delrule); 560 561 static inline size_t fib_rule_nlmsg_size(struct fib_rules_ops *ops, 562 struct fib_rule *rule) 563 { 564 size_t payload = NLMSG_ALIGN(sizeof(struct fib_rule_hdr)) 565 + nla_total_size(IFNAMSIZ) /* FRA_IIFNAME */ 566 + nla_total_size(IFNAMSIZ) /* FRA_OIFNAME */ 567 + nla_total_size(4) /* FRA_PRIORITY */ 568 + nla_total_size(4) /* FRA_TABLE */ 569 + nla_total_size(4) /* FRA_SUPPRESS_PREFIXLEN */ 570 + nla_total_size(4) /* FRA_SUPPRESS_IFGROUP */ 571 + nla_total_size(4) /* FRA_FWMARK */ 572 + nla_total_size(4) /* FRA_FWMASK */ 573 + nla_total_size_64bit(8); /* FRA_TUN_ID */ 574 575 if (ops->nlmsg_payload) 576 payload += ops->nlmsg_payload(rule); 577 578 return payload; 579 } 580 581 static int fib_nl_fill_rule(struct sk_buff *skb, struct fib_rule *rule, 582 u32 pid, u32 seq, int type, int flags, 583 struct fib_rules_ops *ops) 584 { 585 struct nlmsghdr *nlh; 586 struct fib_rule_hdr *frh; 587 588 nlh = nlmsg_put(skb, pid, seq, type, sizeof(*frh), flags); 589 if (nlh == NULL) 590 return -EMSGSIZE; 591 592 frh = nlmsg_data(nlh); 593 frh->family = ops->family; 594 frh->table = rule->table; 595 if (nla_put_u32(skb, FRA_TABLE, rule->table)) 596 goto nla_put_failure; 597 if (nla_put_u32(skb, FRA_SUPPRESS_PREFIXLEN, rule->suppress_prefixlen)) 598 goto nla_put_failure; 599 frh->res1 = 0; 600 frh->res2 = 0; 601 frh->action = rule->action; 602 frh->flags = rule->flags; 603 604 if (rule->action == FR_ACT_GOTO && 605 rcu_access_pointer(rule->ctarget) == NULL) 606 frh->flags |= FIB_RULE_UNRESOLVED; 607 608 if (rule->iifname[0]) { 609 if (nla_put_string(skb, FRA_IIFNAME, rule->iifname)) 610 goto nla_put_failure; 611 if (rule->iifindex == -1) 612 frh->flags |= FIB_RULE_IIF_DETACHED; 613 } 614 615 if (rule->oifname[0]) { 616 if (nla_put_string(skb, FRA_OIFNAME, rule->oifname)) 617 goto nla_put_failure; 618 if (rule->oifindex == -1) 619 frh->flags |= FIB_RULE_OIF_DETACHED; 620 } 621 622 if ((rule->pref && 623 nla_put_u32(skb, FRA_PRIORITY, rule->pref)) || 624 (rule->mark && 625 nla_put_u32(skb, FRA_FWMARK, rule->mark)) || 626 ((rule->mark_mask || rule->mark) && 627 nla_put_u32(skb, FRA_FWMASK, rule->mark_mask)) || 628 (rule->target && 629 nla_put_u32(skb, FRA_GOTO, rule->target)) || 630 (rule->tun_id && 631 nla_put_be64(skb, FRA_TUN_ID, rule->tun_id, FRA_PAD)) || 632 (rule->l3mdev && 633 nla_put_u8(skb, FRA_L3MDEV, rule->l3mdev))) 634 goto nla_put_failure; 635 636 if (rule->suppress_ifgroup != -1) { 637 if (nla_put_u32(skb, FRA_SUPPRESS_IFGROUP, rule->suppress_ifgroup)) 638 goto nla_put_failure; 639 } 640 641 if (ops->fill(rule, skb, frh) < 0) 642 goto nla_put_failure; 643 644 nlmsg_end(skb, nlh); 645 return 0; 646 647 nla_put_failure: 648 nlmsg_cancel(skb, nlh); 649 return -EMSGSIZE; 650 } 651 652 static int dump_rules(struct sk_buff *skb, struct netlink_callback *cb, 653 struct fib_rules_ops *ops) 654 { 655 int idx = 0; 656 struct fib_rule *rule; 657 int err = 0; 658 659 rcu_read_lock(); 660 list_for_each_entry_rcu(rule, &ops->rules_list, list) { 661 if (idx < cb->args[1]) 662 goto skip; 663 664 err = fib_nl_fill_rule(skb, rule, NETLINK_CB(cb->skb).portid, 665 cb->nlh->nlmsg_seq, RTM_NEWRULE, 666 NLM_F_MULTI, ops); 667 if (err) 668 break; 669 skip: 670 idx++; 671 } 672 rcu_read_unlock(); 673 cb->args[1] = idx; 674 rules_ops_put(ops); 675 676 return err; 677 } 678 679 static int fib_nl_dumprule(struct sk_buff *skb, struct netlink_callback *cb) 680 { 681 struct net *net = sock_net(skb->sk); 682 struct fib_rules_ops *ops; 683 int idx = 0, family; 684 685 family = rtnl_msg_family(cb->nlh); 686 if (family != AF_UNSPEC) { 687 /* Protocol specific dump request */ 688 ops = lookup_rules_ops(net, family); 689 if (ops == NULL) 690 return -EAFNOSUPPORT; 691 692 dump_rules(skb, cb, ops); 693 694 return skb->len; 695 } 696 697 rcu_read_lock(); 698 list_for_each_entry_rcu(ops, &net->rules_ops, list) { 699 if (idx < cb->args[0] || !try_module_get(ops->owner)) 700 goto skip; 701 702 if (dump_rules(skb, cb, ops) < 0) 703 break; 704 705 cb->args[1] = 0; 706 skip: 707 idx++; 708 } 709 rcu_read_unlock(); 710 cb->args[0] = idx; 711 712 return skb->len; 713 } 714 715 static void notify_rule_change(int event, struct fib_rule *rule, 716 struct fib_rules_ops *ops, struct nlmsghdr *nlh, 717 u32 pid) 718 { 719 struct net *net; 720 struct sk_buff *skb; 721 int err = -ENOBUFS; 722 723 net = ops->fro_net; 724 skb = nlmsg_new(fib_rule_nlmsg_size(ops, rule), GFP_KERNEL); 725 if (skb == NULL) 726 goto errout; 727 728 err = fib_nl_fill_rule(skb, rule, pid, nlh->nlmsg_seq, event, 0, ops); 729 if (err < 0) { 730 /* -EMSGSIZE implies BUG in fib_rule_nlmsg_size() */ 731 WARN_ON(err == -EMSGSIZE); 732 kfree_skb(skb); 733 goto errout; 734 } 735 736 rtnl_notify(skb, net, pid, ops->nlgroup, nlh, GFP_KERNEL); 737 return; 738 errout: 739 if (err < 0) 740 rtnl_set_sk_err(net, ops->nlgroup, err); 741 } 742 743 static void attach_rules(struct list_head *rules, struct net_device *dev) 744 { 745 struct fib_rule *rule; 746 747 list_for_each_entry(rule, rules, list) { 748 if (rule->iifindex == -1 && 749 strcmp(dev->name, rule->iifname) == 0) 750 rule->iifindex = dev->ifindex; 751 if (rule->oifindex == -1 && 752 strcmp(dev->name, rule->oifname) == 0) 753 rule->oifindex = dev->ifindex; 754 } 755 } 756 757 static void detach_rules(struct list_head *rules, struct net_device *dev) 758 { 759 struct fib_rule *rule; 760 761 list_for_each_entry(rule, rules, list) { 762 if (rule->iifindex == dev->ifindex) 763 rule->iifindex = -1; 764 if (rule->oifindex == dev->ifindex) 765 rule->oifindex = -1; 766 } 767 } 768 769 770 static int fib_rules_event(struct notifier_block *this, unsigned long event, 771 void *ptr) 772 { 773 struct net_device *dev = netdev_notifier_info_to_dev(ptr); 774 struct net *net = dev_net(dev); 775 struct fib_rules_ops *ops; 776 777 ASSERT_RTNL(); 778 779 switch (event) { 780 case NETDEV_REGISTER: 781 list_for_each_entry(ops, &net->rules_ops, list) 782 attach_rules(&ops->rules_list, dev); 783 break; 784 785 case NETDEV_CHANGENAME: 786 list_for_each_entry(ops, &net->rules_ops, list) { 787 detach_rules(&ops->rules_list, dev); 788 attach_rules(&ops->rules_list, dev); 789 } 790 break; 791 792 case NETDEV_UNREGISTER: 793 list_for_each_entry(ops, &net->rules_ops, list) 794 detach_rules(&ops->rules_list, dev); 795 break; 796 } 797 798 return NOTIFY_DONE; 799 } 800 801 static struct notifier_block fib_rules_notifier = { 802 .notifier_call = fib_rules_event, 803 }; 804 805 static int __net_init fib_rules_net_init(struct net *net) 806 { 807 INIT_LIST_HEAD(&net->rules_ops); 808 spin_lock_init(&net->rules_mod_lock); 809 return 0; 810 } 811 812 static struct pernet_operations fib_rules_net_ops = { 813 .init = fib_rules_net_init, 814 }; 815 816 static int __init fib_rules_init(void) 817 { 818 int err; 819 rtnl_register(PF_UNSPEC, RTM_NEWRULE, fib_nl_newrule, NULL, NULL); 820 rtnl_register(PF_UNSPEC, RTM_DELRULE, fib_nl_delrule, NULL, NULL); 821 rtnl_register(PF_UNSPEC, RTM_GETRULE, NULL, fib_nl_dumprule, NULL); 822 823 err = register_pernet_subsys(&fib_rules_net_ops); 824 if (err < 0) 825 goto fail; 826 827 err = register_netdevice_notifier(&fib_rules_notifier); 828 if (err < 0) 829 goto fail_unregister; 830 831 return 0; 832 833 fail_unregister: 834 unregister_pernet_subsys(&fib_rules_net_ops); 835 fail: 836 rtnl_unregister(PF_UNSPEC, RTM_NEWRULE); 837 rtnl_unregister(PF_UNSPEC, RTM_DELRULE); 838 rtnl_unregister(PF_UNSPEC, RTM_GETRULE); 839 return err; 840 } 841 842 subsys_initcall(fib_rules_init); 843