1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * net/core/fib_rules.c Generic Routing Rules 4 * 5 * Authors: Thomas Graf <tgraf@suug.ch> 6 */ 7 8 #include <linux/types.h> 9 #include <linux/kernel.h> 10 #include <linux/slab.h> 11 #include <linux/list.h> 12 #include <linux/module.h> 13 #include <net/net_namespace.h> 14 #include <net/inet_dscp.h> 15 #include <net/sock.h> 16 #include <net/fib_rules.h> 17 #include <net/ip_tunnels.h> 18 #include <linux/indirect_call_wrapper.h> 19 20 #if defined(CONFIG_IPV6) && defined(CONFIG_IPV6_MULTIPLE_TABLES) 21 #ifdef CONFIG_IP_MULTIPLE_TABLES 22 #define INDIRECT_CALL_MT(f, f2, f1, ...) \ 23 INDIRECT_CALL_INET(f, f2, f1, __VA_ARGS__) 24 #else 25 #define INDIRECT_CALL_MT(f, f2, f1, ...) INDIRECT_CALL_1(f, f2, __VA_ARGS__) 26 #endif 27 #elif defined(CONFIG_IP_MULTIPLE_TABLES) 28 #define INDIRECT_CALL_MT(f, f2, f1, ...) INDIRECT_CALL_1(f, f1, __VA_ARGS__) 29 #else 30 #define INDIRECT_CALL_MT(f, f2, f1, ...) f(__VA_ARGS__) 31 #endif 32 33 static const struct fib_kuid_range fib_kuid_range_unset = { 34 KUIDT_INIT(0), 35 KUIDT_INIT(~0), 36 }; 37 38 bool fib_rule_matchall(const struct fib_rule *rule) 39 { 40 if (READ_ONCE(rule->iifindex) || READ_ONCE(rule->oifindex) || 41 rule->mark || rule->tun_id || rule->flags) 42 return false; 43 if (rule->suppress_ifgroup != -1 || rule->suppress_prefixlen != -1) 44 return false; 45 if (!uid_eq(rule->uid_range.start, fib_kuid_range_unset.start) || 46 !uid_eq(rule->uid_range.end, fib_kuid_range_unset.end)) 47 return false; 48 if (fib_rule_port_range_set(&rule->sport_range)) 49 return false; 50 if (fib_rule_port_range_set(&rule->dport_range)) 51 return false; 52 return true; 53 } 54 EXPORT_SYMBOL_GPL(fib_rule_matchall); 55 56 int fib_default_rule_add(struct fib_rules_ops *ops, 57 u32 pref, u32 table) 58 { 59 struct fib_rule *r; 60 61 r = kzalloc(ops->rule_size, GFP_KERNEL_ACCOUNT); 62 if (r == NULL) 63 return -ENOMEM; 64 65 refcount_set(&r->refcnt, 1); 66 r->action = FR_ACT_TO_TBL; 67 r->pref = pref; 68 r->table = table; 69 r->proto = RTPROT_KERNEL; 70 r->fr_net = ops->fro_net; 71 r->uid_range = fib_kuid_range_unset; 72 73 r->suppress_prefixlen = -1; 74 r->suppress_ifgroup = -1; 75 76 /* The lock is not required here, the list in unreachable 77 * at the moment this function is called */ 78 list_add_tail(&r->list, &ops->rules_list); 79 return 0; 80 } 81 EXPORT_SYMBOL(fib_default_rule_add); 82 83 static u32 fib_default_rule_pref(struct fib_rules_ops *ops) 84 { 85 struct list_head *pos; 86 struct fib_rule *rule; 87 88 if (!list_empty(&ops->rules_list)) { 89 pos = ops->rules_list.next; 90 if (pos->next != &ops->rules_list) { 91 rule = list_entry(pos->next, struct fib_rule, list); 92 if (rule->pref) 93 return rule->pref - 1; 94 } 95 } 96 97 return 0; 98 } 99 100 static void notify_rule_change(int event, struct fib_rule *rule, 101 struct fib_rules_ops *ops, struct nlmsghdr *nlh, 102 u32 pid); 103 104 static struct fib_rules_ops *lookup_rules_ops(const struct net *net, 105 int family) 106 { 107 struct fib_rules_ops *ops; 108 109 rcu_read_lock(); 110 list_for_each_entry_rcu(ops, &net->rules_ops, list) { 111 if (ops->family == family) { 112 if (!try_module_get(ops->owner)) 113 ops = NULL; 114 rcu_read_unlock(); 115 return ops; 116 } 117 } 118 rcu_read_unlock(); 119 120 return NULL; 121 } 122 123 static void rules_ops_put(struct fib_rules_ops *ops) 124 { 125 if (ops) 126 module_put(ops->owner); 127 } 128 129 static void flush_route_cache(struct fib_rules_ops *ops) 130 { 131 if (ops->flush_cache) 132 ops->flush_cache(ops); 133 } 134 135 static int __fib_rules_register(struct fib_rules_ops *ops) 136 { 137 int err = -EEXIST; 138 struct fib_rules_ops *o; 139 struct net *net; 140 141 net = ops->fro_net; 142 143 if (ops->rule_size < sizeof(struct fib_rule)) 144 return -EINVAL; 145 146 if (ops->match == NULL || ops->configure == NULL || 147 ops->compare == NULL || ops->fill == NULL || 148 ops->action == NULL) 149 return -EINVAL; 150 151 spin_lock(&net->rules_mod_lock); 152 list_for_each_entry(o, &net->rules_ops, list) 153 if (ops->family == o->family) 154 goto errout; 155 156 list_add_tail_rcu(&ops->list, &net->rules_ops); 157 err = 0; 158 errout: 159 spin_unlock(&net->rules_mod_lock); 160 161 return err; 162 } 163 164 struct fib_rules_ops * 165 fib_rules_register(const struct fib_rules_ops *tmpl, struct net *net) 166 { 167 struct fib_rules_ops *ops; 168 int err; 169 170 ops = kmemdup(tmpl, sizeof(*ops), GFP_KERNEL); 171 if (ops == NULL) 172 return ERR_PTR(-ENOMEM); 173 174 INIT_LIST_HEAD(&ops->rules_list); 175 ops->fro_net = net; 176 177 err = __fib_rules_register(ops); 178 if (err) { 179 kfree(ops); 180 ops = ERR_PTR(err); 181 } 182 183 return ops; 184 } 185 EXPORT_SYMBOL_GPL(fib_rules_register); 186 187 static void fib_rules_cleanup_ops(struct fib_rules_ops *ops) 188 { 189 struct fib_rule *rule, *tmp; 190 191 list_for_each_entry_safe(rule, tmp, &ops->rules_list, list) { 192 list_del_rcu(&rule->list); 193 if (ops->delete) 194 ops->delete(rule); 195 fib_rule_put(rule); 196 } 197 } 198 199 void fib_rules_unregister(struct fib_rules_ops *ops) 200 { 201 struct net *net = ops->fro_net; 202 203 spin_lock(&net->rules_mod_lock); 204 list_del_rcu(&ops->list); 205 spin_unlock(&net->rules_mod_lock); 206 207 fib_rules_cleanup_ops(ops); 208 kfree_rcu(ops, rcu); 209 } 210 EXPORT_SYMBOL_GPL(fib_rules_unregister); 211 212 static int uid_range_set(struct fib_kuid_range *range) 213 { 214 return uid_valid(range->start) && uid_valid(range->end); 215 } 216 217 static struct fib_kuid_range nla_get_kuid_range(struct nlattr **tb) 218 { 219 struct fib_rule_uid_range *in; 220 struct fib_kuid_range out; 221 222 in = (struct fib_rule_uid_range *)nla_data(tb[FRA_UID_RANGE]); 223 224 out.start = make_kuid(current_user_ns(), in->start); 225 out.end = make_kuid(current_user_ns(), in->end); 226 227 return out; 228 } 229 230 static int nla_put_uid_range(struct sk_buff *skb, struct fib_kuid_range *range) 231 { 232 struct fib_rule_uid_range out = { 233 from_kuid_munged(current_user_ns(), range->start), 234 from_kuid_munged(current_user_ns(), range->end) 235 }; 236 237 return nla_put(skb, FRA_UID_RANGE, sizeof(out), &out); 238 } 239 240 static int nla_get_port_range(struct nlattr *pattr, 241 struct fib_rule_port_range *port_range) 242 { 243 const struct fib_rule_port_range *pr = nla_data(pattr); 244 245 if (!fib_rule_port_range_valid(pr)) 246 return -EINVAL; 247 248 port_range->start = pr->start; 249 port_range->end = pr->end; 250 251 return 0; 252 } 253 254 static int nla_put_port_range(struct sk_buff *skb, int attrtype, 255 struct fib_rule_port_range *range) 256 { 257 return nla_put(skb, attrtype, sizeof(*range), range); 258 } 259 260 static bool fib_rule_iif_match(const struct fib_rule *rule, int iifindex, 261 const struct flowi *fl) 262 { 263 u8 iif_is_l3_master = READ_ONCE(rule->iif_is_l3_master); 264 265 return iif_is_l3_master ? l3mdev_fib_rule_iif_match(fl, iifindex) : 266 fl->flowi_iif == iifindex; 267 } 268 269 static bool fib_rule_oif_match(const struct fib_rule *rule, int oifindex, 270 const struct flowi *fl) 271 { 272 u8 oif_is_l3_master = READ_ONCE(rule->oif_is_l3_master); 273 274 return oif_is_l3_master ? l3mdev_fib_rule_oif_match(fl, oifindex) : 275 fl->flowi_oif == oifindex; 276 } 277 278 static int fib_rule_match(struct fib_rule *rule, struct fib_rules_ops *ops, 279 struct flowi *fl, int flags, 280 struct fib_lookup_arg *arg) 281 { 282 int iifindex, oifindex, ret = 0; 283 284 iifindex = READ_ONCE(rule->iifindex); 285 if (iifindex && !fib_rule_iif_match(rule, iifindex, fl)) 286 goto out; 287 288 oifindex = READ_ONCE(rule->oifindex); 289 if (oifindex && !fib_rule_oif_match(rule, oifindex, fl)) 290 goto out; 291 292 if ((rule->mark ^ fl->flowi_mark) & rule->mark_mask) 293 goto out; 294 295 if (rule->tun_id && (rule->tun_id != fl->flowi_tun_key.tun_id)) 296 goto out; 297 298 if (rule->l3mdev && !l3mdev_fib_rule_match(rule->fr_net, fl, arg)) 299 goto out; 300 301 if (uid_lt(fl->flowi_uid, rule->uid_range.start) || 302 uid_gt(fl->flowi_uid, rule->uid_range.end)) 303 goto out; 304 305 ret = INDIRECT_CALL_MT(ops->match, 306 fib6_rule_match, 307 fib4_rule_match, 308 rule, fl, flags); 309 out: 310 return (rule->flags & FIB_RULE_INVERT) ? !ret : ret; 311 } 312 313 int fib_rules_lookup(struct fib_rules_ops *ops, struct flowi *fl, 314 int flags, struct fib_lookup_arg *arg) 315 { 316 struct fib_rule *rule; 317 int err; 318 319 rcu_read_lock(); 320 321 list_for_each_entry_rcu(rule, &ops->rules_list, list) { 322 jumped: 323 if (!fib_rule_match(rule, ops, fl, flags, arg)) 324 continue; 325 326 if (rule->action == FR_ACT_GOTO) { 327 struct fib_rule *target; 328 329 target = rcu_dereference(rule->ctarget); 330 if (target == NULL) { 331 continue; 332 } else { 333 rule = target; 334 goto jumped; 335 } 336 } else if (rule->action == FR_ACT_NOP) 337 continue; 338 else 339 err = INDIRECT_CALL_MT(ops->action, 340 fib6_rule_action, 341 fib4_rule_action, 342 rule, fl, flags, arg); 343 344 if (!err && ops->suppress && INDIRECT_CALL_MT(ops->suppress, 345 fib6_rule_suppress, 346 fib4_rule_suppress, 347 rule, flags, arg)) 348 continue; 349 350 if (err != -EAGAIN) { 351 if ((arg->flags & FIB_LOOKUP_NOREF) || 352 likely(fib_rule_get_safe(rule))) { 353 arg->rule = rule; 354 goto out; 355 } 356 break; 357 } 358 } 359 360 err = -ESRCH; 361 out: 362 rcu_read_unlock(); 363 364 return err; 365 } 366 EXPORT_SYMBOL_GPL(fib_rules_lookup); 367 368 static int call_fib_rule_notifier(struct notifier_block *nb, 369 enum fib_event_type event_type, 370 struct fib_rule *rule, int family, 371 struct netlink_ext_ack *extack) 372 { 373 struct fib_rule_notifier_info info = { 374 .info.family = family, 375 .info.extack = extack, 376 .rule = rule, 377 }; 378 379 return call_fib_notifier(nb, event_type, &info.info); 380 } 381 382 static int call_fib_rule_notifiers(struct net *net, 383 enum fib_event_type event_type, 384 struct fib_rule *rule, 385 struct fib_rules_ops *ops, 386 struct netlink_ext_ack *extack) 387 { 388 struct fib_rule_notifier_info info = { 389 .info.family = ops->family, 390 .info.extack = extack, 391 .rule = rule, 392 }; 393 394 ASSERT_RTNL_NET(net); 395 396 /* Paired with READ_ONCE() in fib_rules_seq() */ 397 WRITE_ONCE(ops->fib_rules_seq, ops->fib_rules_seq + 1); 398 return call_fib_notifiers(net, event_type, &info.info); 399 } 400 401 /* Called with rcu_read_lock() */ 402 int fib_rules_dump(struct net *net, struct notifier_block *nb, int family, 403 struct netlink_ext_ack *extack) 404 { 405 struct fib_rules_ops *ops; 406 struct fib_rule *rule; 407 int err = 0; 408 409 ops = lookup_rules_ops(net, family); 410 if (!ops) 411 return -EAFNOSUPPORT; 412 list_for_each_entry_rcu(rule, &ops->rules_list, list) { 413 if (!fib_rule_get_safe(rule)) 414 continue; 415 416 err = call_fib_rule_notifier(nb, FIB_EVENT_RULE_ADD, 417 rule, family, extack); 418 fib_rule_put(rule); 419 if (err) 420 break; 421 } 422 rules_ops_put(ops); 423 424 return err; 425 } 426 EXPORT_SYMBOL_GPL(fib_rules_dump); 427 428 unsigned int fib_rules_seq_read(const struct net *net, int family) 429 { 430 unsigned int fib_rules_seq; 431 struct fib_rules_ops *ops; 432 433 ops = lookup_rules_ops(net, family); 434 if (!ops) 435 return 0; 436 /* Paired with WRITE_ONCE() in call_fib_rule_notifiers() */ 437 fib_rules_seq = READ_ONCE(ops->fib_rules_seq); 438 rules_ops_put(ops); 439 440 return fib_rules_seq; 441 } 442 EXPORT_SYMBOL_GPL(fib_rules_seq_read); 443 444 static struct fib_rule *rule_find(struct fib_rules_ops *ops, 445 struct fib_rule_hdr *frh, 446 struct nlattr **tb, 447 struct fib_rule *rule, 448 bool user_priority) 449 { 450 struct fib_rule *r; 451 452 list_for_each_entry(r, &ops->rules_list, list) { 453 if (rule->action && r->action != rule->action) 454 continue; 455 456 if (rule->table && r->table != rule->table) 457 continue; 458 459 if (user_priority && r->pref != rule->pref) 460 continue; 461 462 if (rule->iifname[0] && 463 memcmp(r->iifname, rule->iifname, IFNAMSIZ)) 464 continue; 465 466 if (rule->oifname[0] && 467 memcmp(r->oifname, rule->oifname, IFNAMSIZ)) 468 continue; 469 470 if (rule->mark && r->mark != rule->mark) 471 continue; 472 473 if (rule->suppress_ifgroup != -1 && 474 r->suppress_ifgroup != rule->suppress_ifgroup) 475 continue; 476 477 if (rule->suppress_prefixlen != -1 && 478 r->suppress_prefixlen != rule->suppress_prefixlen) 479 continue; 480 481 if (rule->mark_mask && r->mark_mask != rule->mark_mask) 482 continue; 483 484 if (rule->tun_id && r->tun_id != rule->tun_id) 485 continue; 486 487 if (rule->l3mdev && r->l3mdev != rule->l3mdev) 488 continue; 489 490 if (uid_range_set(&rule->uid_range) && 491 (!uid_eq(r->uid_range.start, rule->uid_range.start) || 492 !uid_eq(r->uid_range.end, rule->uid_range.end))) 493 continue; 494 495 if (rule->ip_proto && r->ip_proto != rule->ip_proto) 496 continue; 497 498 if (rule->proto && r->proto != rule->proto) 499 continue; 500 501 if (fib_rule_port_range_set(&rule->sport_range) && 502 !fib_rule_port_range_compare(&r->sport_range, 503 &rule->sport_range)) 504 continue; 505 506 if (rule->sport_mask && r->sport_mask != rule->sport_mask) 507 continue; 508 509 if (fib_rule_port_range_set(&rule->dport_range) && 510 !fib_rule_port_range_compare(&r->dport_range, 511 &rule->dport_range)) 512 continue; 513 514 if (rule->dport_mask && r->dport_mask != rule->dport_mask) 515 continue; 516 517 if (!ops->compare(r, frh, tb)) 518 continue; 519 return r; 520 } 521 522 return NULL; 523 } 524 525 #ifdef CONFIG_NET_L3_MASTER_DEV 526 static int fib_nl2rule_l3mdev(struct nlattr *nla, struct fib_rule *nlrule, 527 struct netlink_ext_ack *extack) 528 { 529 nlrule->l3mdev = nla_get_u8(nla); 530 if (nlrule->l3mdev != 1) { 531 NL_SET_ERR_MSG(extack, "Invalid l3mdev attribute"); 532 return -1; 533 } 534 535 return 0; 536 } 537 #else 538 static int fib_nl2rule_l3mdev(struct nlattr *nla, struct fib_rule *nlrule, 539 struct netlink_ext_ack *extack) 540 { 541 NL_SET_ERR_MSG(extack, "l3mdev support is not enabled in kernel"); 542 return -1; 543 } 544 #endif 545 546 static int fib_nl2rule_port_mask(const struct nlattr *mask_attr, 547 const struct fib_rule_port_range *range, 548 u16 *port_mask, 549 struct netlink_ext_ack *extack) 550 { 551 if (!fib_rule_port_range_valid(range)) { 552 NL_SET_ERR_MSG_ATTR(extack, mask_attr, 553 "Cannot specify port mask without port value"); 554 return -EINVAL; 555 } 556 557 if (fib_rule_port_is_range(range)) { 558 NL_SET_ERR_MSG_ATTR(extack, mask_attr, 559 "Cannot specify port mask for port range"); 560 return -EINVAL; 561 } 562 563 if (range->start & ~nla_get_u16(mask_attr)) { 564 NL_SET_ERR_MSG_ATTR(extack, mask_attr, "Invalid port mask"); 565 return -EINVAL; 566 } 567 568 *port_mask = nla_get_u16(mask_attr); 569 570 return 0; 571 } 572 573 static int fib_nl2rule(struct net *net, struct nlmsghdr *nlh, 574 struct netlink_ext_ack *extack, 575 struct fib_rules_ops *ops, 576 struct nlattr *tb[], 577 struct fib_rule **rule, 578 bool *user_priority) 579 { 580 struct fib_rule_hdr *frh = nlmsg_data(nlh); 581 struct fib_rule *nlrule = NULL; 582 int err = -EINVAL; 583 584 if (frh->src_len) 585 if (!tb[FRA_SRC] || 586 frh->src_len > (ops->addr_size * 8) || 587 nla_len(tb[FRA_SRC]) != ops->addr_size) { 588 NL_SET_ERR_MSG(extack, "Invalid source address"); 589 goto errout; 590 } 591 592 if (frh->dst_len) 593 if (!tb[FRA_DST] || 594 frh->dst_len > (ops->addr_size * 8) || 595 nla_len(tb[FRA_DST]) != ops->addr_size) { 596 NL_SET_ERR_MSG(extack, "Invalid dst address"); 597 goto errout; 598 } 599 600 nlrule = kzalloc(ops->rule_size, GFP_KERNEL_ACCOUNT); 601 if (!nlrule) { 602 err = -ENOMEM; 603 goto errout; 604 } 605 refcount_set(&nlrule->refcnt, 1); 606 nlrule->fr_net = net; 607 608 if (tb[FRA_PRIORITY]) { 609 nlrule->pref = nla_get_u32(tb[FRA_PRIORITY]); 610 *user_priority = true; 611 } 612 613 nlrule->proto = nla_get_u8_default(tb[FRA_PROTOCOL], RTPROT_UNSPEC); 614 615 if (tb[FRA_IIFNAME]) { 616 nlrule->iifindex = -1; 617 nla_strscpy(nlrule->iifname, tb[FRA_IIFNAME], IFNAMSIZ); 618 } 619 620 if (tb[FRA_OIFNAME]) { 621 nlrule->oifindex = -1; 622 nla_strscpy(nlrule->oifname, tb[FRA_OIFNAME], IFNAMSIZ); 623 } 624 625 if (tb[FRA_FWMARK]) { 626 nlrule->mark = nla_get_u32(tb[FRA_FWMARK]); 627 if (nlrule->mark) 628 /* compatibility: if the mark value is non-zero all bits 629 * are compared unless a mask is explicitly specified. 630 */ 631 nlrule->mark_mask = 0xFFFFFFFF; 632 } 633 634 if (tb[FRA_FWMASK]) 635 nlrule->mark_mask = nla_get_u32(tb[FRA_FWMASK]); 636 637 if (tb[FRA_TUN_ID]) 638 nlrule->tun_id = nla_get_be64(tb[FRA_TUN_ID]); 639 640 if (tb[FRA_L3MDEV] && 641 fib_nl2rule_l3mdev(tb[FRA_L3MDEV], nlrule, extack) < 0) 642 goto errout_free; 643 644 nlrule->action = frh->action; 645 nlrule->flags = frh->flags; 646 nlrule->table = frh_get_table(frh, tb); 647 if (tb[FRA_SUPPRESS_PREFIXLEN]) 648 nlrule->suppress_prefixlen = nla_get_u32(tb[FRA_SUPPRESS_PREFIXLEN]); 649 else 650 nlrule->suppress_prefixlen = -1; 651 652 if (tb[FRA_SUPPRESS_IFGROUP]) 653 nlrule->suppress_ifgroup = nla_get_u32(tb[FRA_SUPPRESS_IFGROUP]); 654 else 655 nlrule->suppress_ifgroup = -1; 656 657 if (tb[FRA_GOTO]) { 658 if (nlrule->action != FR_ACT_GOTO) { 659 NL_SET_ERR_MSG(extack, "Unexpected goto"); 660 goto errout_free; 661 } 662 663 nlrule->target = nla_get_u32(tb[FRA_GOTO]); 664 } else if (nlrule->action == FR_ACT_GOTO) { 665 NL_SET_ERR_MSG(extack, "Missing goto target for action goto"); 666 goto errout_free; 667 } 668 669 if (nlrule->l3mdev && nlrule->table) { 670 NL_SET_ERR_MSG(extack, "l3mdev and table are mutually exclusive"); 671 goto errout_free; 672 } 673 674 if (tb[FRA_UID_RANGE]) { 675 if (current_user_ns() != net->user_ns) { 676 err = -EPERM; 677 NL_SET_ERR_MSG(extack, "No permission to set uid"); 678 goto errout_free; 679 } 680 681 nlrule->uid_range = nla_get_kuid_range(tb); 682 683 if (!uid_range_set(&nlrule->uid_range) || 684 !uid_lte(nlrule->uid_range.start, nlrule->uid_range.end)) { 685 NL_SET_ERR_MSG(extack, "Invalid uid range"); 686 goto errout_free; 687 } 688 } else { 689 nlrule->uid_range = fib_kuid_range_unset; 690 } 691 692 if (tb[FRA_IP_PROTO]) 693 nlrule->ip_proto = nla_get_u8(tb[FRA_IP_PROTO]); 694 695 if (tb[FRA_SPORT_RANGE]) { 696 err = nla_get_port_range(tb[FRA_SPORT_RANGE], 697 &nlrule->sport_range); 698 if (err) { 699 NL_SET_ERR_MSG(extack, "Invalid sport range"); 700 goto errout_free; 701 } 702 if (!fib_rule_port_is_range(&nlrule->sport_range)) 703 nlrule->sport_mask = U16_MAX; 704 } 705 706 if (tb[FRA_SPORT_MASK]) { 707 err = fib_nl2rule_port_mask(tb[FRA_SPORT_MASK], 708 &nlrule->sport_range, 709 &nlrule->sport_mask, extack); 710 if (err) 711 goto errout_free; 712 } 713 714 if (tb[FRA_DPORT_RANGE]) { 715 err = nla_get_port_range(tb[FRA_DPORT_RANGE], 716 &nlrule->dport_range); 717 if (err) { 718 NL_SET_ERR_MSG(extack, "Invalid dport range"); 719 goto errout_free; 720 } 721 if (!fib_rule_port_is_range(&nlrule->dport_range)) 722 nlrule->dport_mask = U16_MAX; 723 } 724 725 if (tb[FRA_DPORT_MASK]) { 726 err = fib_nl2rule_port_mask(tb[FRA_DPORT_MASK], 727 &nlrule->dport_range, 728 &nlrule->dport_mask, extack); 729 if (err) 730 goto errout_free; 731 } 732 733 *rule = nlrule; 734 735 return 0; 736 737 errout_free: 738 kfree(nlrule); 739 errout: 740 return err; 741 } 742 743 static int fib_nl2rule_rtnl(struct fib_rule *nlrule, 744 struct fib_rules_ops *ops, 745 struct nlattr *tb[], 746 struct netlink_ext_ack *extack) 747 { 748 if (!tb[FRA_PRIORITY]) 749 nlrule->pref = fib_default_rule_pref(ops); 750 751 /* Backward jumps are prohibited to avoid endless loops */ 752 if (tb[FRA_GOTO] && nlrule->target <= nlrule->pref) { 753 NL_SET_ERR_MSG(extack, "Backward goto not supported"); 754 return -EINVAL; 755 } 756 757 if (tb[FRA_IIFNAME]) { 758 struct net_device *dev; 759 760 dev = __dev_get_by_name(nlrule->fr_net, nlrule->iifname); 761 if (dev) { 762 nlrule->iifindex = dev->ifindex; 763 nlrule->iif_is_l3_master = netif_is_l3_master(dev); 764 } 765 } 766 767 if (tb[FRA_OIFNAME]) { 768 struct net_device *dev; 769 770 dev = __dev_get_by_name(nlrule->fr_net, nlrule->oifname); 771 if (dev) { 772 nlrule->oifindex = dev->ifindex; 773 nlrule->oif_is_l3_master = netif_is_l3_master(dev); 774 } 775 } 776 777 return 0; 778 } 779 780 static int rule_exists(struct fib_rules_ops *ops, struct fib_rule_hdr *frh, 781 struct nlattr **tb, struct fib_rule *rule) 782 { 783 struct fib_rule *r; 784 785 list_for_each_entry(r, &ops->rules_list, list) { 786 if (r->action != rule->action) 787 continue; 788 789 if (r->table != rule->table) 790 continue; 791 792 if (r->pref != rule->pref) 793 continue; 794 795 if (memcmp(r->iifname, rule->iifname, IFNAMSIZ)) 796 continue; 797 798 if (memcmp(r->oifname, rule->oifname, IFNAMSIZ)) 799 continue; 800 801 if (r->mark != rule->mark) 802 continue; 803 804 if (r->suppress_ifgroup != rule->suppress_ifgroup) 805 continue; 806 807 if (r->suppress_prefixlen != rule->suppress_prefixlen) 808 continue; 809 810 if (r->mark_mask != rule->mark_mask) 811 continue; 812 813 if (r->tun_id != rule->tun_id) 814 continue; 815 816 if (r->l3mdev != rule->l3mdev) 817 continue; 818 819 if (!uid_eq(r->uid_range.start, rule->uid_range.start) || 820 !uid_eq(r->uid_range.end, rule->uid_range.end)) 821 continue; 822 823 if (r->ip_proto != rule->ip_proto) 824 continue; 825 826 if (r->proto != rule->proto) 827 continue; 828 829 if (!fib_rule_port_range_compare(&r->sport_range, 830 &rule->sport_range)) 831 continue; 832 833 if (r->sport_mask != rule->sport_mask) 834 continue; 835 836 if (!fib_rule_port_range_compare(&r->dport_range, 837 &rule->dport_range)) 838 continue; 839 840 if (r->dport_mask != rule->dport_mask) 841 continue; 842 843 if (!ops->compare(r, frh, tb)) 844 continue; 845 return 1; 846 } 847 return 0; 848 } 849 850 static const struct nla_policy fib_rule_policy[FRA_MAX + 1] = { 851 [FRA_UNSPEC] = { .strict_start_type = FRA_DPORT_RANGE + 1 }, 852 [FRA_IIFNAME] = { .type = NLA_STRING, .len = IFNAMSIZ - 1 }, 853 [FRA_OIFNAME] = { .type = NLA_STRING, .len = IFNAMSIZ - 1 }, 854 [FRA_PRIORITY] = { .type = NLA_U32 }, 855 [FRA_FWMARK] = { .type = NLA_U32 }, 856 [FRA_FLOW] = { .type = NLA_U32 }, 857 [FRA_TUN_ID] = { .type = NLA_U64 }, 858 [FRA_FWMASK] = { .type = NLA_U32 }, 859 [FRA_TABLE] = { .type = NLA_U32 }, 860 [FRA_SUPPRESS_PREFIXLEN] = { .type = NLA_U32 }, 861 [FRA_SUPPRESS_IFGROUP] = { .type = NLA_U32 }, 862 [FRA_GOTO] = { .type = NLA_U32 }, 863 [FRA_L3MDEV] = { .type = NLA_U8 }, 864 [FRA_UID_RANGE] = { .len = sizeof(struct fib_rule_uid_range) }, 865 [FRA_PROTOCOL] = { .type = NLA_U8 }, 866 [FRA_IP_PROTO] = { .type = NLA_U8 }, 867 [FRA_SPORT_RANGE] = { .len = sizeof(struct fib_rule_port_range) }, 868 [FRA_DPORT_RANGE] = { .len = sizeof(struct fib_rule_port_range) }, 869 [FRA_DSCP] = NLA_POLICY_MAX(NLA_U8, INET_DSCP_MASK >> 2), 870 [FRA_FLOWLABEL] = { .type = NLA_BE32 }, 871 [FRA_FLOWLABEL_MASK] = { .type = NLA_BE32 }, 872 [FRA_SPORT_MASK] = { .type = NLA_U16 }, 873 [FRA_DPORT_MASK] = { .type = NLA_U16 }, 874 [FRA_DSCP_MASK] = NLA_POLICY_MASK(NLA_U8, INET_DSCP_MASK >> 2), 875 }; 876 877 int fib_newrule(struct net *net, struct sk_buff *skb, struct nlmsghdr *nlh, 878 struct netlink_ext_ack *extack, bool rtnl_held) 879 { 880 struct fib_rule *rule = NULL, *r, *last = NULL; 881 int err = -EINVAL, unresolved = 0; 882 struct fib_rules_ops *ops = NULL; 883 struct nlattr *tb[FRA_MAX + 1]; 884 bool user_priority = false; 885 struct fib_rule_hdr *frh; 886 887 frh = nlmsg_payload(nlh, sizeof(*frh)); 888 if (!frh) { 889 NL_SET_ERR_MSG(extack, "Invalid msg length"); 890 goto errout; 891 } 892 893 ops = lookup_rules_ops(net, frh->family); 894 if (!ops) { 895 err = -EAFNOSUPPORT; 896 NL_SET_ERR_MSG(extack, "Rule family not supported"); 897 goto errout; 898 } 899 900 err = nlmsg_parse_deprecated(nlh, sizeof(*frh), tb, FRA_MAX, 901 fib_rule_policy, extack); 902 if (err < 0) { 903 NL_SET_ERR_MSG(extack, "Error parsing msg"); 904 goto errout; 905 } 906 907 err = fib_nl2rule(net, nlh, extack, ops, tb, &rule, &user_priority); 908 if (err) 909 goto errout; 910 911 if (!rtnl_held) 912 rtnl_net_lock(net); 913 914 err = fib_nl2rule_rtnl(rule, ops, tb, extack); 915 if (err) 916 goto errout_free; 917 918 if ((nlh->nlmsg_flags & NLM_F_EXCL) && 919 rule_exists(ops, frh, tb, rule)) { 920 err = -EEXIST; 921 goto errout_free; 922 } 923 924 err = ops->configure(rule, skb, frh, tb, extack); 925 if (err < 0) 926 goto errout_free; 927 928 err = call_fib_rule_notifiers(net, FIB_EVENT_RULE_ADD, rule, ops, 929 extack); 930 if (err < 0) 931 goto errout_free; 932 933 list_for_each_entry(r, &ops->rules_list, list) { 934 if (r->pref == rule->target) { 935 RCU_INIT_POINTER(rule->ctarget, r); 936 break; 937 } 938 } 939 940 if (rcu_dereference_protected(rule->ctarget, 1) == NULL) 941 unresolved = 1; 942 943 list_for_each_entry(r, &ops->rules_list, list) { 944 if (r->pref > rule->pref) 945 break; 946 last = r; 947 } 948 949 if (last) 950 list_add_rcu(&rule->list, &last->list); 951 else 952 list_add_rcu(&rule->list, &ops->rules_list); 953 954 if (ops->unresolved_rules) { 955 /* 956 * There are unresolved goto rules in the list, check if 957 * any of them are pointing to this new rule. 958 */ 959 list_for_each_entry(r, &ops->rules_list, list) { 960 if (r->action == FR_ACT_GOTO && 961 r->target == rule->pref && 962 rtnl_dereference(r->ctarget) == NULL) { 963 rcu_assign_pointer(r->ctarget, rule); 964 if (--ops->unresolved_rules == 0) 965 break; 966 } 967 } 968 } 969 970 if (rule->action == FR_ACT_GOTO) 971 ops->nr_goto_rules++; 972 973 if (unresolved) 974 ops->unresolved_rules++; 975 976 if (rule->tun_id) 977 ip_tunnel_need_metadata(); 978 979 fib_rule_get(rule); 980 981 if (!rtnl_held) 982 rtnl_net_unlock(net); 983 984 notify_rule_change(RTM_NEWRULE, rule, ops, nlh, NETLINK_CB(skb).portid); 985 fib_rule_put(rule); 986 flush_route_cache(ops); 987 rules_ops_put(ops); 988 return 0; 989 990 errout_free: 991 if (!rtnl_held) 992 rtnl_net_unlock(net); 993 kfree(rule); 994 errout: 995 rules_ops_put(ops); 996 return err; 997 } 998 EXPORT_SYMBOL_GPL(fib_newrule); 999 1000 static int fib_nl_newrule(struct sk_buff *skb, struct nlmsghdr *nlh, 1001 struct netlink_ext_ack *extack) 1002 { 1003 return fib_newrule(sock_net(skb->sk), skb, nlh, extack, false); 1004 } 1005 1006 int fib_delrule(struct net *net, struct sk_buff *skb, struct nlmsghdr *nlh, 1007 struct netlink_ext_ack *extack, bool rtnl_held) 1008 { 1009 struct fib_rule *rule = NULL, *nlrule = NULL; 1010 struct fib_rules_ops *ops = NULL; 1011 struct nlattr *tb[FRA_MAX+1]; 1012 bool user_priority = false; 1013 struct fib_rule_hdr *frh; 1014 int err = -EINVAL; 1015 1016 frh = nlmsg_payload(nlh, sizeof(*frh)); 1017 if (!frh) { 1018 NL_SET_ERR_MSG(extack, "Invalid msg length"); 1019 goto errout; 1020 } 1021 1022 ops = lookup_rules_ops(net, frh->family); 1023 if (ops == NULL) { 1024 err = -EAFNOSUPPORT; 1025 NL_SET_ERR_MSG(extack, "Rule family not supported"); 1026 goto errout; 1027 } 1028 1029 err = nlmsg_parse_deprecated(nlh, sizeof(*frh), tb, FRA_MAX, 1030 fib_rule_policy, extack); 1031 if (err < 0) { 1032 NL_SET_ERR_MSG(extack, "Error parsing msg"); 1033 goto errout; 1034 } 1035 1036 err = fib_nl2rule(net, nlh, extack, ops, tb, &nlrule, &user_priority); 1037 if (err) 1038 goto errout; 1039 1040 if (!rtnl_held) 1041 rtnl_net_lock(net); 1042 1043 err = fib_nl2rule_rtnl(nlrule, ops, tb, extack); 1044 if (err) 1045 goto errout_free; 1046 1047 rule = rule_find(ops, frh, tb, nlrule, user_priority); 1048 if (!rule) { 1049 err = -ENOENT; 1050 goto errout_free; 1051 } 1052 1053 if (rule->flags & FIB_RULE_PERMANENT) { 1054 err = -EPERM; 1055 goto errout_free; 1056 } 1057 1058 if (ops->delete) { 1059 err = ops->delete(rule); 1060 if (err) 1061 goto errout_free; 1062 } 1063 1064 if (rule->tun_id) 1065 ip_tunnel_unneed_metadata(); 1066 1067 list_del_rcu(&rule->list); 1068 1069 if (rule->action == FR_ACT_GOTO) { 1070 ops->nr_goto_rules--; 1071 if (rtnl_dereference(rule->ctarget) == NULL) 1072 ops->unresolved_rules--; 1073 } 1074 1075 /* 1076 * Check if this rule is a target to any of them. If so, 1077 * adjust to the next one with the same preference or 1078 * disable them. As this operation is eventually very 1079 * expensive, it is only performed if goto rules, except 1080 * current if it is goto rule, have actually been added. 1081 */ 1082 if (ops->nr_goto_rules > 0) { 1083 struct fib_rule *n, *r; 1084 1085 n = list_next_entry(rule, list); 1086 if (&n->list == &ops->rules_list || n->pref != rule->pref) 1087 n = NULL; 1088 list_for_each_entry(r, &ops->rules_list, list) { 1089 if (rtnl_dereference(r->ctarget) != rule) 1090 continue; 1091 rcu_assign_pointer(r->ctarget, n); 1092 if (!n) 1093 ops->unresolved_rules++; 1094 } 1095 } 1096 1097 call_fib_rule_notifiers(net, FIB_EVENT_RULE_DEL, rule, ops, NULL); 1098 1099 if (!rtnl_held) 1100 rtnl_net_unlock(net); 1101 1102 notify_rule_change(RTM_DELRULE, rule, ops, nlh, NETLINK_CB(skb).portid); 1103 fib_rule_put(rule); 1104 flush_route_cache(ops); 1105 rules_ops_put(ops); 1106 kfree(nlrule); 1107 return 0; 1108 1109 errout_free: 1110 if (!rtnl_held) 1111 rtnl_net_unlock(net); 1112 kfree(nlrule); 1113 errout: 1114 rules_ops_put(ops); 1115 return err; 1116 } 1117 EXPORT_SYMBOL_GPL(fib_delrule); 1118 1119 static int fib_nl_delrule(struct sk_buff *skb, struct nlmsghdr *nlh, 1120 struct netlink_ext_ack *extack) 1121 { 1122 return fib_delrule(sock_net(skb->sk), skb, nlh, extack, false); 1123 } 1124 1125 static inline size_t fib_rule_nlmsg_size(struct fib_rules_ops *ops, 1126 struct fib_rule *rule) 1127 { 1128 size_t payload = NLMSG_ALIGN(sizeof(struct fib_rule_hdr)) 1129 + nla_total_size(IFNAMSIZ) /* FRA_IIFNAME */ 1130 + nla_total_size(IFNAMSIZ) /* FRA_OIFNAME */ 1131 + nla_total_size(4) /* FRA_PRIORITY */ 1132 + nla_total_size(4) /* FRA_TABLE */ 1133 + nla_total_size(4) /* FRA_SUPPRESS_PREFIXLEN */ 1134 + nla_total_size(4) /* FRA_SUPPRESS_IFGROUP */ 1135 + nla_total_size(4) /* FRA_FWMARK */ 1136 + nla_total_size(4) /* FRA_FWMASK */ 1137 + nla_total_size_64bit(8) /* FRA_TUN_ID */ 1138 + nla_total_size(sizeof(struct fib_kuid_range)) 1139 + nla_total_size(1) /* FRA_PROTOCOL */ 1140 + nla_total_size(1) /* FRA_IP_PROTO */ 1141 + nla_total_size(sizeof(struct fib_rule_port_range)) /* FRA_SPORT_RANGE */ 1142 + nla_total_size(sizeof(struct fib_rule_port_range)) /* FRA_DPORT_RANGE */ 1143 + nla_total_size(2) /* FRA_SPORT_MASK */ 1144 + nla_total_size(2); /* FRA_DPORT_MASK */ 1145 1146 if (ops->nlmsg_payload) 1147 payload += ops->nlmsg_payload(rule); 1148 1149 return payload; 1150 } 1151 1152 static int fib_nl_fill_rule(struct sk_buff *skb, struct fib_rule *rule, 1153 u32 pid, u32 seq, int type, int flags, 1154 struct fib_rules_ops *ops) 1155 { 1156 struct nlmsghdr *nlh; 1157 struct fib_rule_hdr *frh; 1158 1159 nlh = nlmsg_put(skb, pid, seq, type, sizeof(*frh), flags); 1160 if (nlh == NULL) 1161 return -EMSGSIZE; 1162 1163 frh = nlmsg_data(nlh); 1164 frh->family = ops->family; 1165 frh->table = rule->table < 256 ? rule->table : RT_TABLE_COMPAT; 1166 if (nla_put_u32(skb, FRA_TABLE, rule->table)) 1167 goto nla_put_failure; 1168 if (nla_put_u32(skb, FRA_SUPPRESS_PREFIXLEN, rule->suppress_prefixlen)) 1169 goto nla_put_failure; 1170 frh->res1 = 0; 1171 frh->res2 = 0; 1172 frh->action = rule->action; 1173 frh->flags = rule->flags; 1174 1175 if (nla_put_u8(skb, FRA_PROTOCOL, rule->proto)) 1176 goto nla_put_failure; 1177 1178 if (rule->action == FR_ACT_GOTO && 1179 rcu_access_pointer(rule->ctarget) == NULL) 1180 frh->flags |= FIB_RULE_UNRESOLVED; 1181 1182 if (rule->iifname[0]) { 1183 if (nla_put_string(skb, FRA_IIFNAME, rule->iifname)) 1184 goto nla_put_failure; 1185 if (READ_ONCE(rule->iifindex) == -1) 1186 frh->flags |= FIB_RULE_IIF_DETACHED; 1187 } 1188 1189 if (rule->oifname[0]) { 1190 if (nla_put_string(skb, FRA_OIFNAME, rule->oifname)) 1191 goto nla_put_failure; 1192 if (READ_ONCE(rule->oifindex) == -1) 1193 frh->flags |= FIB_RULE_OIF_DETACHED; 1194 } 1195 1196 if ((rule->pref && 1197 nla_put_u32(skb, FRA_PRIORITY, rule->pref)) || 1198 (rule->mark && 1199 nla_put_u32(skb, FRA_FWMARK, rule->mark)) || 1200 ((rule->mark_mask || rule->mark) && 1201 nla_put_u32(skb, FRA_FWMASK, rule->mark_mask)) || 1202 (rule->target && 1203 nla_put_u32(skb, FRA_GOTO, rule->target)) || 1204 (rule->tun_id && 1205 nla_put_be64(skb, FRA_TUN_ID, rule->tun_id, FRA_PAD)) || 1206 (rule->l3mdev && 1207 nla_put_u8(skb, FRA_L3MDEV, rule->l3mdev)) || 1208 (uid_range_set(&rule->uid_range) && 1209 nla_put_uid_range(skb, &rule->uid_range)) || 1210 (fib_rule_port_range_set(&rule->sport_range) && 1211 nla_put_port_range(skb, FRA_SPORT_RANGE, &rule->sport_range)) || 1212 (rule->sport_mask && nla_put_u16(skb, FRA_SPORT_MASK, 1213 rule->sport_mask)) || 1214 (fib_rule_port_range_set(&rule->dport_range) && 1215 nla_put_port_range(skb, FRA_DPORT_RANGE, &rule->dport_range)) || 1216 (rule->dport_mask && nla_put_u16(skb, FRA_DPORT_MASK, 1217 rule->dport_mask)) || 1218 (rule->ip_proto && nla_put_u8(skb, FRA_IP_PROTO, rule->ip_proto))) 1219 goto nla_put_failure; 1220 1221 if (rule->suppress_ifgroup != -1) { 1222 if (nla_put_u32(skb, FRA_SUPPRESS_IFGROUP, rule->suppress_ifgroup)) 1223 goto nla_put_failure; 1224 } 1225 1226 if (ops->fill(rule, skb, frh) < 0) 1227 goto nla_put_failure; 1228 1229 nlmsg_end(skb, nlh); 1230 return 0; 1231 1232 nla_put_failure: 1233 nlmsg_cancel(skb, nlh); 1234 return -EMSGSIZE; 1235 } 1236 1237 static int dump_rules(struct sk_buff *skb, struct netlink_callback *cb, 1238 struct fib_rules_ops *ops) 1239 { 1240 int idx = 0; 1241 struct fib_rule *rule; 1242 int err = 0; 1243 1244 rcu_read_lock(); 1245 list_for_each_entry_rcu(rule, &ops->rules_list, list) { 1246 if (idx < cb->args[1]) 1247 goto skip; 1248 1249 err = fib_nl_fill_rule(skb, rule, NETLINK_CB(cb->skb).portid, 1250 cb->nlh->nlmsg_seq, RTM_NEWRULE, 1251 NLM_F_MULTI, ops); 1252 if (err) 1253 break; 1254 skip: 1255 idx++; 1256 } 1257 rcu_read_unlock(); 1258 cb->args[1] = idx; 1259 rules_ops_put(ops); 1260 1261 return err; 1262 } 1263 1264 static int fib_valid_dumprule_req(const struct nlmsghdr *nlh, 1265 struct netlink_ext_ack *extack) 1266 { 1267 struct fib_rule_hdr *frh; 1268 1269 frh = nlmsg_payload(nlh, sizeof(*frh)); 1270 if (!frh) { 1271 NL_SET_ERR_MSG(extack, "Invalid header for fib rule dump request"); 1272 return -EINVAL; 1273 } 1274 1275 if (frh->dst_len || frh->src_len || frh->tos || frh->table || 1276 frh->res1 || frh->res2 || frh->action || frh->flags) { 1277 NL_SET_ERR_MSG(extack, 1278 "Invalid values in header for fib rule dump request"); 1279 return -EINVAL; 1280 } 1281 1282 if (nlmsg_attrlen(nlh, sizeof(*frh))) { 1283 NL_SET_ERR_MSG(extack, "Invalid data after header in fib rule dump request"); 1284 return -EINVAL; 1285 } 1286 1287 return 0; 1288 } 1289 1290 static int fib_nl_dumprule(struct sk_buff *skb, struct netlink_callback *cb) 1291 { 1292 const struct nlmsghdr *nlh = cb->nlh; 1293 struct net *net = sock_net(skb->sk); 1294 struct fib_rules_ops *ops; 1295 int err, idx = 0, family; 1296 1297 if (cb->strict_check) { 1298 err = fib_valid_dumprule_req(nlh, cb->extack); 1299 1300 if (err < 0) 1301 return err; 1302 } 1303 1304 family = rtnl_msg_family(nlh); 1305 if (family != AF_UNSPEC) { 1306 /* Protocol specific dump request */ 1307 ops = lookup_rules_ops(net, family); 1308 if (ops == NULL) 1309 return -EAFNOSUPPORT; 1310 1311 return dump_rules(skb, cb, ops); 1312 } 1313 1314 err = 0; 1315 rcu_read_lock(); 1316 list_for_each_entry_rcu(ops, &net->rules_ops, list) { 1317 if (idx < cb->args[0] || !try_module_get(ops->owner)) 1318 goto skip; 1319 1320 err = dump_rules(skb, cb, ops); 1321 if (err < 0) 1322 break; 1323 1324 cb->args[1] = 0; 1325 skip: 1326 idx++; 1327 } 1328 rcu_read_unlock(); 1329 cb->args[0] = idx; 1330 1331 return err; 1332 } 1333 1334 static void notify_rule_change(int event, struct fib_rule *rule, 1335 struct fib_rules_ops *ops, struct nlmsghdr *nlh, 1336 u32 pid) 1337 { 1338 struct net *net; 1339 struct sk_buff *skb; 1340 int err = -ENOMEM; 1341 1342 net = ops->fro_net; 1343 skb = nlmsg_new(fib_rule_nlmsg_size(ops, rule), GFP_KERNEL); 1344 if (skb == NULL) 1345 goto errout; 1346 1347 err = fib_nl_fill_rule(skb, rule, pid, nlh->nlmsg_seq, event, 0, ops); 1348 if (err < 0) { 1349 /* -EMSGSIZE implies BUG in fib_rule_nlmsg_size() */ 1350 WARN_ON(err == -EMSGSIZE); 1351 kfree_skb(skb); 1352 goto errout; 1353 } 1354 1355 rtnl_notify(skb, net, pid, ops->nlgroup, nlh, GFP_KERNEL); 1356 return; 1357 errout: 1358 rtnl_set_sk_err(net, ops->nlgroup, err); 1359 } 1360 1361 static void attach_rules(struct list_head *rules, struct net_device *dev) 1362 { 1363 struct fib_rule *rule; 1364 1365 list_for_each_entry(rule, rules, list) { 1366 if (rule->iifindex == -1 && 1367 strcmp(dev->name, rule->iifname) == 0) { 1368 WRITE_ONCE(rule->iifindex, dev->ifindex); 1369 WRITE_ONCE(rule->iif_is_l3_master, 1370 netif_is_l3_master(dev)); 1371 } 1372 if (rule->oifindex == -1 && 1373 strcmp(dev->name, rule->oifname) == 0) { 1374 WRITE_ONCE(rule->oifindex, dev->ifindex); 1375 WRITE_ONCE(rule->oif_is_l3_master, 1376 netif_is_l3_master(dev)); 1377 } 1378 } 1379 } 1380 1381 static void detach_rules(struct list_head *rules, struct net_device *dev) 1382 { 1383 struct fib_rule *rule; 1384 1385 list_for_each_entry(rule, rules, list) { 1386 if (rule->iifindex == dev->ifindex) { 1387 WRITE_ONCE(rule->iifindex, -1); 1388 WRITE_ONCE(rule->iif_is_l3_master, false); 1389 } 1390 if (rule->oifindex == dev->ifindex) { 1391 WRITE_ONCE(rule->oifindex, -1); 1392 WRITE_ONCE(rule->oif_is_l3_master, false); 1393 } 1394 } 1395 } 1396 1397 1398 static int fib_rules_event(struct notifier_block *this, unsigned long event, 1399 void *ptr) 1400 { 1401 struct net_device *dev = netdev_notifier_info_to_dev(ptr); 1402 struct net *net = dev_net(dev); 1403 struct fib_rules_ops *ops; 1404 1405 ASSERT_RTNL(); 1406 1407 switch (event) { 1408 case NETDEV_REGISTER: 1409 list_for_each_entry(ops, &net->rules_ops, list) 1410 attach_rules(&ops->rules_list, dev); 1411 break; 1412 1413 case NETDEV_CHANGENAME: 1414 list_for_each_entry(ops, &net->rules_ops, list) { 1415 detach_rules(&ops->rules_list, dev); 1416 attach_rules(&ops->rules_list, dev); 1417 } 1418 break; 1419 1420 case NETDEV_UNREGISTER: 1421 list_for_each_entry(ops, &net->rules_ops, list) 1422 detach_rules(&ops->rules_list, dev); 1423 break; 1424 } 1425 1426 return NOTIFY_DONE; 1427 } 1428 1429 static struct notifier_block fib_rules_notifier = { 1430 .notifier_call = fib_rules_event, 1431 }; 1432 1433 static int __net_init fib_rules_net_init(struct net *net) 1434 { 1435 INIT_LIST_HEAD(&net->rules_ops); 1436 spin_lock_init(&net->rules_mod_lock); 1437 return 0; 1438 } 1439 1440 static void __net_exit fib_rules_net_exit(struct net *net) 1441 { 1442 WARN_ON_ONCE(!list_empty(&net->rules_ops)); 1443 } 1444 1445 static struct pernet_operations fib_rules_net_ops = { 1446 .init = fib_rules_net_init, 1447 .exit = fib_rules_net_exit, 1448 }; 1449 1450 static const struct rtnl_msg_handler fib_rules_rtnl_msg_handlers[] __initconst = { 1451 {.msgtype = RTM_NEWRULE, .doit = fib_nl_newrule, 1452 .flags = RTNL_FLAG_DOIT_PERNET}, 1453 {.msgtype = RTM_DELRULE, .doit = fib_nl_delrule, 1454 .flags = RTNL_FLAG_DOIT_PERNET}, 1455 {.msgtype = RTM_GETRULE, .dumpit = fib_nl_dumprule, 1456 .flags = RTNL_FLAG_DUMP_UNLOCKED}, 1457 }; 1458 1459 static int __init fib_rules_init(void) 1460 { 1461 int err; 1462 1463 rtnl_register_many(fib_rules_rtnl_msg_handlers); 1464 1465 err = register_pernet_subsys(&fib_rules_net_ops); 1466 if (err < 0) 1467 goto fail; 1468 1469 err = register_netdevice_notifier(&fib_rules_notifier); 1470 if (err < 0) 1471 goto fail_unregister; 1472 1473 return 0; 1474 1475 fail_unregister: 1476 unregister_pernet_subsys(&fib_rules_net_ops); 1477 fail: 1478 rtnl_unregister_many(fib_rules_rtnl_msg_handlers); 1479 return err; 1480 } 1481 1482 subsys_initcall(fib_rules_init); 1483