1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * net/sched/cls_api.c Packet classifier API. 4 * 5 * Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru> 6 * 7 * Changes: 8 * 9 * Eduardo J. Blanco <ejbs@netlabs.com.uy> :990222: kmod support 10 */ 11 12 #include <linux/module.h> 13 #include <linux/types.h> 14 #include <linux/kernel.h> 15 #include <linux/string.h> 16 #include <linux/errno.h> 17 #include <linux/err.h> 18 #include <linux/skbuff.h> 19 #include <linux/init.h> 20 #include <linux/kmod.h> 21 #include <linux/slab.h> 22 #include <linux/idr.h> 23 #include <linux/rhashtable.h> 24 #include <linux/jhash.h> 25 #include <net/net_namespace.h> 26 #include <net/sock.h> 27 #include <net/netlink.h> 28 #include <net/pkt_sched.h> 29 #include <net/pkt_cls.h> 30 #include <net/tc_act/tc_pedit.h> 31 #include <net/tc_act/tc_mirred.h> 32 #include <net/tc_act/tc_vlan.h> 33 #include <net/tc_act/tc_tunnel_key.h> 34 #include <net/tc_act/tc_csum.h> 35 #include <net/tc_act/tc_gact.h> 36 #include <net/tc_act/tc_police.h> 37 #include <net/tc_act/tc_sample.h> 38 #include <net/tc_act/tc_skbedit.h> 39 #include <net/tc_act/tc_ct.h> 40 #include <net/tc_act/tc_mpls.h> 41 #include <net/flow_offload.h> 42 43 extern const struct nla_policy rtm_tca_policy[TCA_MAX + 1]; 44 45 /* The list of all installed classifier types */ 46 static LIST_HEAD(tcf_proto_base); 47 48 /* Protects list of registered TC modules. It is pure SMP lock. */ 49 static DEFINE_RWLOCK(cls_mod_lock); 50 51 static u32 destroy_obj_hashfn(const struct tcf_proto *tp) 52 { 53 return jhash_3words(tp->chain->index, tp->prio, 54 (__force __u32)tp->protocol, 0); 55 } 56 57 static void tcf_proto_signal_destroying(struct tcf_chain *chain, 58 struct tcf_proto *tp) 59 { 60 struct tcf_block *block = chain->block; 61 62 mutex_lock(&block->proto_destroy_lock); 63 hash_add_rcu(block->proto_destroy_ht, &tp->destroy_ht_node, 64 destroy_obj_hashfn(tp)); 65 mutex_unlock(&block->proto_destroy_lock); 66 } 67 68 static bool tcf_proto_cmp(const struct tcf_proto *tp1, 69 const struct tcf_proto *tp2) 70 { 71 return tp1->chain->index == tp2->chain->index && 72 tp1->prio == tp2->prio && 73 tp1->protocol == tp2->protocol; 74 } 75 76 static bool tcf_proto_exists_destroying(struct tcf_chain *chain, 77 struct tcf_proto *tp) 78 { 79 u32 hash = destroy_obj_hashfn(tp); 80 struct tcf_proto *iter; 81 bool found = false; 82 83 rcu_read_lock(); 84 hash_for_each_possible_rcu(chain->block->proto_destroy_ht, iter, 85 destroy_ht_node, hash) { 86 if (tcf_proto_cmp(tp, iter)) { 87 found = true; 88 break; 89 } 90 } 91 rcu_read_unlock(); 92 93 return found; 94 } 95 96 static void 97 tcf_proto_signal_destroyed(struct tcf_chain *chain, struct tcf_proto *tp) 98 { 99 struct tcf_block *block = chain->block; 100 101 mutex_lock(&block->proto_destroy_lock); 102 if (hash_hashed(&tp->destroy_ht_node)) 103 hash_del_rcu(&tp->destroy_ht_node); 104 mutex_unlock(&block->proto_destroy_lock); 105 } 106 107 /* Find classifier type by string name */ 108 109 static const struct tcf_proto_ops *__tcf_proto_lookup_ops(const char *kind) 110 { 111 const struct tcf_proto_ops *t, *res = NULL; 112 113 if (kind) { 114 read_lock(&cls_mod_lock); 115 list_for_each_entry(t, &tcf_proto_base, head) { 116 if (strcmp(kind, t->kind) == 0) { 117 if (try_module_get(t->owner)) 118 res = t; 119 break; 120 } 121 } 122 read_unlock(&cls_mod_lock); 123 } 124 return res; 125 } 126 127 static const struct tcf_proto_ops * 128 tcf_proto_lookup_ops(const char *kind, bool rtnl_held, 129 struct netlink_ext_ack *extack) 130 { 131 const struct tcf_proto_ops *ops; 132 133 ops = __tcf_proto_lookup_ops(kind); 134 if (ops) 135 return ops; 136 #ifdef CONFIG_MODULES 137 if (rtnl_held) 138 rtnl_unlock(); 139 request_module("cls_%s", kind); 140 if (rtnl_held) 141 rtnl_lock(); 142 ops = __tcf_proto_lookup_ops(kind); 143 /* We dropped the RTNL semaphore in order to perform 144 * the module load. So, even if we succeeded in loading 145 * the module we have to replay the request. We indicate 146 * this using -EAGAIN. 147 */ 148 if (ops) { 149 module_put(ops->owner); 150 return ERR_PTR(-EAGAIN); 151 } 152 #endif 153 NL_SET_ERR_MSG(extack, "TC classifier not found"); 154 return ERR_PTR(-ENOENT); 155 } 156 157 /* Register(unregister) new classifier type */ 158 159 int register_tcf_proto_ops(struct tcf_proto_ops *ops) 160 { 161 struct tcf_proto_ops *t; 162 int rc = -EEXIST; 163 164 write_lock(&cls_mod_lock); 165 list_for_each_entry(t, &tcf_proto_base, head) 166 if (!strcmp(ops->kind, t->kind)) 167 goto out; 168 169 list_add_tail(&ops->head, &tcf_proto_base); 170 rc = 0; 171 out: 172 write_unlock(&cls_mod_lock); 173 return rc; 174 } 175 EXPORT_SYMBOL(register_tcf_proto_ops); 176 177 static struct workqueue_struct *tc_filter_wq; 178 179 int unregister_tcf_proto_ops(struct tcf_proto_ops *ops) 180 { 181 struct tcf_proto_ops *t; 182 int rc = -ENOENT; 183 184 /* Wait for outstanding call_rcu()s, if any, from a 185 * tcf_proto_ops's destroy() handler. 186 */ 187 rcu_barrier(); 188 flush_workqueue(tc_filter_wq); 189 190 write_lock(&cls_mod_lock); 191 list_for_each_entry(t, &tcf_proto_base, head) { 192 if (t == ops) { 193 list_del(&t->head); 194 rc = 0; 195 break; 196 } 197 } 198 write_unlock(&cls_mod_lock); 199 return rc; 200 } 201 EXPORT_SYMBOL(unregister_tcf_proto_ops); 202 203 bool tcf_queue_work(struct rcu_work *rwork, work_func_t func) 204 { 205 INIT_RCU_WORK(rwork, func); 206 return queue_rcu_work(tc_filter_wq, rwork); 207 } 208 EXPORT_SYMBOL(tcf_queue_work); 209 210 /* Select new prio value from the range, managed by kernel. */ 211 212 static inline u32 tcf_auto_prio(struct tcf_proto *tp) 213 { 214 u32 first = TC_H_MAKE(0xC0000000U, 0U); 215 216 if (tp) 217 first = tp->prio - 1; 218 219 return TC_H_MAJ(first); 220 } 221 222 static bool tcf_proto_check_kind(struct nlattr *kind, char *name) 223 { 224 if (kind) 225 return nla_strlcpy(name, kind, IFNAMSIZ) >= IFNAMSIZ; 226 memset(name, 0, IFNAMSIZ); 227 return false; 228 } 229 230 static bool tcf_proto_is_unlocked(const char *kind) 231 { 232 const struct tcf_proto_ops *ops; 233 bool ret; 234 235 if (strlen(kind) == 0) 236 return false; 237 238 ops = tcf_proto_lookup_ops(kind, false, NULL); 239 /* On error return false to take rtnl lock. Proto lookup/create 240 * functions will perform lookup again and properly handle errors. 241 */ 242 if (IS_ERR(ops)) 243 return false; 244 245 ret = !!(ops->flags & TCF_PROTO_OPS_DOIT_UNLOCKED); 246 module_put(ops->owner); 247 return ret; 248 } 249 250 static struct tcf_proto *tcf_proto_create(const char *kind, u32 protocol, 251 u32 prio, struct tcf_chain *chain, 252 bool rtnl_held, 253 struct netlink_ext_ack *extack) 254 { 255 struct tcf_proto *tp; 256 int err; 257 258 tp = kzalloc(sizeof(*tp), GFP_KERNEL); 259 if (!tp) 260 return ERR_PTR(-ENOBUFS); 261 262 tp->ops = tcf_proto_lookup_ops(kind, rtnl_held, extack); 263 if (IS_ERR(tp->ops)) { 264 err = PTR_ERR(tp->ops); 265 goto errout; 266 } 267 tp->classify = tp->ops->classify; 268 tp->protocol = protocol; 269 tp->prio = prio; 270 tp->chain = chain; 271 spin_lock_init(&tp->lock); 272 refcount_set(&tp->refcnt, 1); 273 274 err = tp->ops->init(tp); 275 if (err) { 276 module_put(tp->ops->owner); 277 goto errout; 278 } 279 return tp; 280 281 errout: 282 kfree(tp); 283 return ERR_PTR(err); 284 } 285 286 static void tcf_proto_get(struct tcf_proto *tp) 287 { 288 refcount_inc(&tp->refcnt); 289 } 290 291 static void tcf_chain_put(struct tcf_chain *chain); 292 293 static void tcf_proto_destroy(struct tcf_proto *tp, bool rtnl_held, 294 bool sig_destroy, struct netlink_ext_ack *extack) 295 { 296 tp->ops->destroy(tp, rtnl_held, extack); 297 if (sig_destroy) 298 tcf_proto_signal_destroyed(tp->chain, tp); 299 tcf_chain_put(tp->chain); 300 module_put(tp->ops->owner); 301 kfree_rcu(tp, rcu); 302 } 303 304 static void tcf_proto_put(struct tcf_proto *tp, bool rtnl_held, 305 struct netlink_ext_ack *extack) 306 { 307 if (refcount_dec_and_test(&tp->refcnt)) 308 tcf_proto_destroy(tp, rtnl_held, true, extack); 309 } 310 311 static int walker_check_empty(struct tcf_proto *tp, void *fh, 312 struct tcf_walker *arg) 313 { 314 if (fh) { 315 arg->nonempty = true; 316 return -1; 317 } 318 return 0; 319 } 320 321 static bool tcf_proto_is_empty(struct tcf_proto *tp, bool rtnl_held) 322 { 323 struct tcf_walker walker = { .fn = walker_check_empty, }; 324 325 if (tp->ops->walk) { 326 tp->ops->walk(tp, &walker, rtnl_held); 327 return !walker.nonempty; 328 } 329 return true; 330 } 331 332 static bool tcf_proto_check_delete(struct tcf_proto *tp, bool rtnl_held) 333 { 334 spin_lock(&tp->lock); 335 if (tcf_proto_is_empty(tp, rtnl_held)) 336 tp->deleting = true; 337 spin_unlock(&tp->lock); 338 return tp->deleting; 339 } 340 341 static void tcf_proto_mark_delete(struct tcf_proto *tp) 342 { 343 spin_lock(&tp->lock); 344 tp->deleting = true; 345 spin_unlock(&tp->lock); 346 } 347 348 static bool tcf_proto_is_deleting(struct tcf_proto *tp) 349 { 350 bool deleting; 351 352 spin_lock(&tp->lock); 353 deleting = tp->deleting; 354 spin_unlock(&tp->lock); 355 356 return deleting; 357 } 358 359 #define ASSERT_BLOCK_LOCKED(block) \ 360 lockdep_assert_held(&(block)->lock) 361 362 struct tcf_filter_chain_list_item { 363 struct list_head list; 364 tcf_chain_head_change_t *chain_head_change; 365 void *chain_head_change_priv; 366 }; 367 368 static struct tcf_chain *tcf_chain_create(struct tcf_block *block, 369 u32 chain_index) 370 { 371 struct tcf_chain *chain; 372 373 ASSERT_BLOCK_LOCKED(block); 374 375 chain = kzalloc(sizeof(*chain), GFP_KERNEL); 376 if (!chain) 377 return NULL; 378 list_add_tail(&chain->list, &block->chain_list); 379 mutex_init(&chain->filter_chain_lock); 380 chain->block = block; 381 chain->index = chain_index; 382 chain->refcnt = 1; 383 if (!chain->index) 384 block->chain0.chain = chain; 385 return chain; 386 } 387 388 static void tcf_chain_head_change_item(struct tcf_filter_chain_list_item *item, 389 struct tcf_proto *tp_head) 390 { 391 if (item->chain_head_change) 392 item->chain_head_change(tp_head, item->chain_head_change_priv); 393 } 394 395 static void tcf_chain0_head_change(struct tcf_chain *chain, 396 struct tcf_proto *tp_head) 397 { 398 struct tcf_filter_chain_list_item *item; 399 struct tcf_block *block = chain->block; 400 401 if (chain->index) 402 return; 403 404 mutex_lock(&block->lock); 405 list_for_each_entry(item, &block->chain0.filter_chain_list, list) 406 tcf_chain_head_change_item(item, tp_head); 407 mutex_unlock(&block->lock); 408 } 409 410 /* Returns true if block can be safely freed. */ 411 412 static bool tcf_chain_detach(struct tcf_chain *chain) 413 { 414 struct tcf_block *block = chain->block; 415 416 ASSERT_BLOCK_LOCKED(block); 417 418 list_del(&chain->list); 419 if (!chain->index) 420 block->chain0.chain = NULL; 421 422 if (list_empty(&block->chain_list) && 423 refcount_read(&block->refcnt) == 0) 424 return true; 425 426 return false; 427 } 428 429 static void tcf_block_destroy(struct tcf_block *block) 430 { 431 mutex_destroy(&block->lock); 432 mutex_destroy(&block->proto_destroy_lock); 433 kfree_rcu(block, rcu); 434 } 435 436 static void tcf_chain_destroy(struct tcf_chain *chain, bool free_block) 437 { 438 struct tcf_block *block = chain->block; 439 440 mutex_destroy(&chain->filter_chain_lock); 441 kfree_rcu(chain, rcu); 442 if (free_block) 443 tcf_block_destroy(block); 444 } 445 446 static void tcf_chain_hold(struct tcf_chain *chain) 447 { 448 ASSERT_BLOCK_LOCKED(chain->block); 449 450 ++chain->refcnt; 451 } 452 453 static bool tcf_chain_held_by_acts_only(struct tcf_chain *chain) 454 { 455 ASSERT_BLOCK_LOCKED(chain->block); 456 457 /* In case all the references are action references, this 458 * chain should not be shown to the user. 459 */ 460 return chain->refcnt == chain->action_refcnt; 461 } 462 463 static struct tcf_chain *tcf_chain_lookup(struct tcf_block *block, 464 u32 chain_index) 465 { 466 struct tcf_chain *chain; 467 468 ASSERT_BLOCK_LOCKED(block); 469 470 list_for_each_entry(chain, &block->chain_list, list) { 471 if (chain->index == chain_index) 472 return chain; 473 } 474 return NULL; 475 } 476 477 static int tc_chain_notify(struct tcf_chain *chain, struct sk_buff *oskb, 478 u32 seq, u16 flags, int event, bool unicast); 479 480 static struct tcf_chain *__tcf_chain_get(struct tcf_block *block, 481 u32 chain_index, bool create, 482 bool by_act) 483 { 484 struct tcf_chain *chain = NULL; 485 bool is_first_reference; 486 487 mutex_lock(&block->lock); 488 chain = tcf_chain_lookup(block, chain_index); 489 if (chain) { 490 tcf_chain_hold(chain); 491 } else { 492 if (!create) 493 goto errout; 494 chain = tcf_chain_create(block, chain_index); 495 if (!chain) 496 goto errout; 497 } 498 499 if (by_act) 500 ++chain->action_refcnt; 501 is_first_reference = chain->refcnt - chain->action_refcnt == 1; 502 mutex_unlock(&block->lock); 503 504 /* Send notification only in case we got the first 505 * non-action reference. Until then, the chain acts only as 506 * a placeholder for actions pointing to it and user ought 507 * not know about them. 508 */ 509 if (is_first_reference && !by_act) 510 tc_chain_notify(chain, NULL, 0, NLM_F_CREATE | NLM_F_EXCL, 511 RTM_NEWCHAIN, false); 512 513 return chain; 514 515 errout: 516 mutex_unlock(&block->lock); 517 return chain; 518 } 519 520 static struct tcf_chain *tcf_chain_get(struct tcf_block *block, u32 chain_index, 521 bool create) 522 { 523 return __tcf_chain_get(block, chain_index, create, false); 524 } 525 526 struct tcf_chain *tcf_chain_get_by_act(struct tcf_block *block, u32 chain_index) 527 { 528 return __tcf_chain_get(block, chain_index, true, true); 529 } 530 EXPORT_SYMBOL(tcf_chain_get_by_act); 531 532 static void tc_chain_tmplt_del(const struct tcf_proto_ops *tmplt_ops, 533 void *tmplt_priv); 534 static int tc_chain_notify_delete(const struct tcf_proto_ops *tmplt_ops, 535 void *tmplt_priv, u32 chain_index, 536 struct tcf_block *block, struct sk_buff *oskb, 537 u32 seq, u16 flags, bool unicast); 538 539 static void __tcf_chain_put(struct tcf_chain *chain, bool by_act, 540 bool explicitly_created) 541 { 542 struct tcf_block *block = chain->block; 543 const struct tcf_proto_ops *tmplt_ops; 544 bool free_block = false; 545 unsigned int refcnt; 546 void *tmplt_priv; 547 548 mutex_lock(&block->lock); 549 if (explicitly_created) { 550 if (!chain->explicitly_created) { 551 mutex_unlock(&block->lock); 552 return; 553 } 554 chain->explicitly_created = false; 555 } 556 557 if (by_act) 558 chain->action_refcnt--; 559 560 /* tc_chain_notify_delete can't be called while holding block lock. 561 * However, when block is unlocked chain can be changed concurrently, so 562 * save these to temporary variables. 563 */ 564 refcnt = --chain->refcnt; 565 tmplt_ops = chain->tmplt_ops; 566 tmplt_priv = chain->tmplt_priv; 567 568 /* The last dropped non-action reference will trigger notification. */ 569 if (refcnt - chain->action_refcnt == 0 && !by_act) { 570 tc_chain_notify_delete(tmplt_ops, tmplt_priv, chain->index, 571 block, NULL, 0, 0, false); 572 /* Last reference to chain, no need to lock. */ 573 chain->flushing = false; 574 } 575 576 if (refcnt == 0) 577 free_block = tcf_chain_detach(chain); 578 mutex_unlock(&block->lock); 579 580 if (refcnt == 0) { 581 tc_chain_tmplt_del(tmplt_ops, tmplt_priv); 582 tcf_chain_destroy(chain, free_block); 583 } 584 } 585 586 static void tcf_chain_put(struct tcf_chain *chain) 587 { 588 __tcf_chain_put(chain, false, false); 589 } 590 591 void tcf_chain_put_by_act(struct tcf_chain *chain) 592 { 593 __tcf_chain_put(chain, true, false); 594 } 595 EXPORT_SYMBOL(tcf_chain_put_by_act); 596 597 static void tcf_chain_put_explicitly_created(struct tcf_chain *chain) 598 { 599 __tcf_chain_put(chain, false, true); 600 } 601 602 static void tcf_chain_flush(struct tcf_chain *chain, bool rtnl_held) 603 { 604 struct tcf_proto *tp, *tp_next; 605 606 mutex_lock(&chain->filter_chain_lock); 607 tp = tcf_chain_dereference(chain->filter_chain, chain); 608 while (tp) { 609 tp_next = rcu_dereference_protected(tp->next, 1); 610 tcf_proto_signal_destroying(chain, tp); 611 tp = tp_next; 612 } 613 tp = tcf_chain_dereference(chain->filter_chain, chain); 614 RCU_INIT_POINTER(chain->filter_chain, NULL); 615 tcf_chain0_head_change(chain, NULL); 616 chain->flushing = true; 617 mutex_unlock(&chain->filter_chain_lock); 618 619 while (tp) { 620 tp_next = rcu_dereference_protected(tp->next, 1); 621 tcf_proto_put(tp, rtnl_held, NULL); 622 tp = tp_next; 623 } 624 } 625 626 static int tcf_block_setup(struct tcf_block *block, 627 struct flow_block_offload *bo); 628 629 static void tc_indr_block_ing_cmd(struct net_device *dev, 630 struct tcf_block *block, 631 flow_indr_block_bind_cb_t *cb, 632 void *cb_priv, 633 enum flow_block_command command) 634 { 635 struct flow_block_offload bo = { 636 .command = command, 637 .binder_type = FLOW_BLOCK_BINDER_TYPE_CLSACT_INGRESS, 638 .net = dev_net(dev), 639 .block_shared = tcf_block_non_null_shared(block), 640 }; 641 INIT_LIST_HEAD(&bo.cb_list); 642 643 if (!block) 644 return; 645 646 bo.block = &block->flow_block; 647 648 down_write(&block->cb_lock); 649 cb(dev, cb_priv, TC_SETUP_BLOCK, &bo); 650 651 tcf_block_setup(block, &bo); 652 up_write(&block->cb_lock); 653 } 654 655 static struct tcf_block *tc_dev_ingress_block(struct net_device *dev) 656 { 657 const struct Qdisc_class_ops *cops; 658 struct Qdisc *qdisc; 659 660 if (!dev_ingress_queue(dev)) 661 return NULL; 662 663 qdisc = dev_ingress_queue(dev)->qdisc_sleeping; 664 if (!qdisc) 665 return NULL; 666 667 cops = qdisc->ops->cl_ops; 668 if (!cops) 669 return NULL; 670 671 if (!cops->tcf_block) 672 return NULL; 673 674 return cops->tcf_block(qdisc, TC_H_MIN_INGRESS, NULL); 675 } 676 677 static void tc_indr_block_get_and_ing_cmd(struct net_device *dev, 678 flow_indr_block_bind_cb_t *cb, 679 void *cb_priv, 680 enum flow_block_command command) 681 { 682 struct tcf_block *block = tc_dev_ingress_block(dev); 683 684 tc_indr_block_ing_cmd(dev, block, cb, cb_priv, command); 685 } 686 687 static void tc_indr_block_call(struct tcf_block *block, 688 struct net_device *dev, 689 struct tcf_block_ext_info *ei, 690 enum flow_block_command command, 691 struct netlink_ext_ack *extack) 692 { 693 struct flow_block_offload bo = { 694 .command = command, 695 .binder_type = ei->binder_type, 696 .net = dev_net(dev), 697 .block = &block->flow_block, 698 .block_shared = tcf_block_shared(block), 699 .extack = extack, 700 }; 701 INIT_LIST_HEAD(&bo.cb_list); 702 703 flow_indr_block_call(dev, &bo, command); 704 tcf_block_setup(block, &bo); 705 } 706 707 static bool tcf_block_offload_in_use(struct tcf_block *block) 708 { 709 return atomic_read(&block->offloadcnt); 710 } 711 712 static int tcf_block_offload_cmd(struct tcf_block *block, 713 struct net_device *dev, 714 struct tcf_block_ext_info *ei, 715 enum flow_block_command command, 716 struct netlink_ext_ack *extack) 717 { 718 struct flow_block_offload bo = {}; 719 int err; 720 721 bo.net = dev_net(dev); 722 bo.command = command; 723 bo.binder_type = ei->binder_type; 724 bo.block = &block->flow_block; 725 bo.block_shared = tcf_block_shared(block); 726 bo.extack = extack; 727 INIT_LIST_HEAD(&bo.cb_list); 728 729 err = dev->netdev_ops->ndo_setup_tc(dev, TC_SETUP_BLOCK, &bo); 730 if (err < 0) 731 return err; 732 733 return tcf_block_setup(block, &bo); 734 } 735 736 static int tcf_block_offload_bind(struct tcf_block *block, struct Qdisc *q, 737 struct tcf_block_ext_info *ei, 738 struct netlink_ext_ack *extack) 739 { 740 struct net_device *dev = q->dev_queue->dev; 741 int err; 742 743 down_write(&block->cb_lock); 744 if (!dev->netdev_ops->ndo_setup_tc) 745 goto no_offload_dev_inc; 746 747 /* If tc offload feature is disabled and the block we try to bind 748 * to already has some offloaded filters, forbid to bind. 749 */ 750 if (!tc_can_offload(dev) && tcf_block_offload_in_use(block)) { 751 NL_SET_ERR_MSG(extack, "Bind to offloaded block failed as dev has offload disabled"); 752 err = -EOPNOTSUPP; 753 goto err_unlock; 754 } 755 756 err = tcf_block_offload_cmd(block, dev, ei, FLOW_BLOCK_BIND, extack); 757 if (err == -EOPNOTSUPP) 758 goto no_offload_dev_inc; 759 if (err) 760 goto err_unlock; 761 762 tc_indr_block_call(block, dev, ei, FLOW_BLOCK_BIND, extack); 763 up_write(&block->cb_lock); 764 return 0; 765 766 no_offload_dev_inc: 767 if (tcf_block_offload_in_use(block)) { 768 err = -EOPNOTSUPP; 769 goto err_unlock; 770 } 771 err = 0; 772 block->nooffloaddevcnt++; 773 tc_indr_block_call(block, dev, ei, FLOW_BLOCK_BIND, extack); 774 err_unlock: 775 up_write(&block->cb_lock); 776 return err; 777 } 778 779 static void tcf_block_offload_unbind(struct tcf_block *block, struct Qdisc *q, 780 struct tcf_block_ext_info *ei) 781 { 782 struct net_device *dev = q->dev_queue->dev; 783 int err; 784 785 down_write(&block->cb_lock); 786 tc_indr_block_call(block, dev, ei, FLOW_BLOCK_UNBIND, NULL); 787 788 if (!dev->netdev_ops->ndo_setup_tc) 789 goto no_offload_dev_dec; 790 err = tcf_block_offload_cmd(block, dev, ei, FLOW_BLOCK_UNBIND, NULL); 791 if (err == -EOPNOTSUPP) 792 goto no_offload_dev_dec; 793 up_write(&block->cb_lock); 794 return; 795 796 no_offload_dev_dec: 797 WARN_ON(block->nooffloaddevcnt-- == 0); 798 up_write(&block->cb_lock); 799 } 800 801 static int 802 tcf_chain0_head_change_cb_add(struct tcf_block *block, 803 struct tcf_block_ext_info *ei, 804 struct netlink_ext_ack *extack) 805 { 806 struct tcf_filter_chain_list_item *item; 807 struct tcf_chain *chain0; 808 809 item = kmalloc(sizeof(*item), GFP_KERNEL); 810 if (!item) { 811 NL_SET_ERR_MSG(extack, "Memory allocation for head change callback item failed"); 812 return -ENOMEM; 813 } 814 item->chain_head_change = ei->chain_head_change; 815 item->chain_head_change_priv = ei->chain_head_change_priv; 816 817 mutex_lock(&block->lock); 818 chain0 = block->chain0.chain; 819 if (chain0) 820 tcf_chain_hold(chain0); 821 else 822 list_add(&item->list, &block->chain0.filter_chain_list); 823 mutex_unlock(&block->lock); 824 825 if (chain0) { 826 struct tcf_proto *tp_head; 827 828 mutex_lock(&chain0->filter_chain_lock); 829 830 tp_head = tcf_chain_dereference(chain0->filter_chain, chain0); 831 if (tp_head) 832 tcf_chain_head_change_item(item, tp_head); 833 834 mutex_lock(&block->lock); 835 list_add(&item->list, &block->chain0.filter_chain_list); 836 mutex_unlock(&block->lock); 837 838 mutex_unlock(&chain0->filter_chain_lock); 839 tcf_chain_put(chain0); 840 } 841 842 return 0; 843 } 844 845 static void 846 tcf_chain0_head_change_cb_del(struct tcf_block *block, 847 struct tcf_block_ext_info *ei) 848 { 849 struct tcf_filter_chain_list_item *item; 850 851 mutex_lock(&block->lock); 852 list_for_each_entry(item, &block->chain0.filter_chain_list, list) { 853 if ((!ei->chain_head_change && !ei->chain_head_change_priv) || 854 (item->chain_head_change == ei->chain_head_change && 855 item->chain_head_change_priv == ei->chain_head_change_priv)) { 856 if (block->chain0.chain) 857 tcf_chain_head_change_item(item, NULL); 858 list_del(&item->list); 859 mutex_unlock(&block->lock); 860 861 kfree(item); 862 return; 863 } 864 } 865 mutex_unlock(&block->lock); 866 WARN_ON(1); 867 } 868 869 struct tcf_net { 870 spinlock_t idr_lock; /* Protects idr */ 871 struct idr idr; 872 }; 873 874 static unsigned int tcf_net_id; 875 876 static int tcf_block_insert(struct tcf_block *block, struct net *net, 877 struct netlink_ext_ack *extack) 878 { 879 struct tcf_net *tn = net_generic(net, tcf_net_id); 880 int err; 881 882 idr_preload(GFP_KERNEL); 883 spin_lock(&tn->idr_lock); 884 err = idr_alloc_u32(&tn->idr, block, &block->index, block->index, 885 GFP_NOWAIT); 886 spin_unlock(&tn->idr_lock); 887 idr_preload_end(); 888 889 return err; 890 } 891 892 static void tcf_block_remove(struct tcf_block *block, struct net *net) 893 { 894 struct tcf_net *tn = net_generic(net, tcf_net_id); 895 896 spin_lock(&tn->idr_lock); 897 idr_remove(&tn->idr, block->index); 898 spin_unlock(&tn->idr_lock); 899 } 900 901 static struct tcf_block *tcf_block_create(struct net *net, struct Qdisc *q, 902 u32 block_index, 903 struct netlink_ext_ack *extack) 904 { 905 struct tcf_block *block; 906 907 block = kzalloc(sizeof(*block), GFP_KERNEL); 908 if (!block) { 909 NL_SET_ERR_MSG(extack, "Memory allocation for block failed"); 910 return ERR_PTR(-ENOMEM); 911 } 912 mutex_init(&block->lock); 913 mutex_init(&block->proto_destroy_lock); 914 init_rwsem(&block->cb_lock); 915 flow_block_init(&block->flow_block); 916 INIT_LIST_HEAD(&block->chain_list); 917 INIT_LIST_HEAD(&block->owner_list); 918 INIT_LIST_HEAD(&block->chain0.filter_chain_list); 919 920 refcount_set(&block->refcnt, 1); 921 block->net = net; 922 block->index = block_index; 923 924 /* Don't store q pointer for blocks which are shared */ 925 if (!tcf_block_shared(block)) 926 block->q = q; 927 return block; 928 } 929 930 static struct tcf_block *tcf_block_lookup(struct net *net, u32 block_index) 931 { 932 struct tcf_net *tn = net_generic(net, tcf_net_id); 933 934 return idr_find(&tn->idr, block_index); 935 } 936 937 static struct tcf_block *tcf_block_refcnt_get(struct net *net, u32 block_index) 938 { 939 struct tcf_block *block; 940 941 rcu_read_lock(); 942 block = tcf_block_lookup(net, block_index); 943 if (block && !refcount_inc_not_zero(&block->refcnt)) 944 block = NULL; 945 rcu_read_unlock(); 946 947 return block; 948 } 949 950 static struct tcf_chain * 951 __tcf_get_next_chain(struct tcf_block *block, struct tcf_chain *chain) 952 { 953 mutex_lock(&block->lock); 954 if (chain) 955 chain = list_is_last(&chain->list, &block->chain_list) ? 956 NULL : list_next_entry(chain, list); 957 else 958 chain = list_first_entry_or_null(&block->chain_list, 959 struct tcf_chain, list); 960 961 /* skip all action-only chains */ 962 while (chain && tcf_chain_held_by_acts_only(chain)) 963 chain = list_is_last(&chain->list, &block->chain_list) ? 964 NULL : list_next_entry(chain, list); 965 966 if (chain) 967 tcf_chain_hold(chain); 968 mutex_unlock(&block->lock); 969 970 return chain; 971 } 972 973 /* Function to be used by all clients that want to iterate over all chains on 974 * block. It properly obtains block->lock and takes reference to chain before 975 * returning it. Users of this function must be tolerant to concurrent chain 976 * insertion/deletion or ensure that no concurrent chain modification is 977 * possible. Note that all netlink dump callbacks cannot guarantee to provide 978 * consistent dump because rtnl lock is released each time skb is filled with 979 * data and sent to user-space. 980 */ 981 982 struct tcf_chain * 983 tcf_get_next_chain(struct tcf_block *block, struct tcf_chain *chain) 984 { 985 struct tcf_chain *chain_next = __tcf_get_next_chain(block, chain); 986 987 if (chain) 988 tcf_chain_put(chain); 989 990 return chain_next; 991 } 992 EXPORT_SYMBOL(tcf_get_next_chain); 993 994 static struct tcf_proto * 995 __tcf_get_next_proto(struct tcf_chain *chain, struct tcf_proto *tp) 996 { 997 u32 prio = 0; 998 999 ASSERT_RTNL(); 1000 mutex_lock(&chain->filter_chain_lock); 1001 1002 if (!tp) { 1003 tp = tcf_chain_dereference(chain->filter_chain, chain); 1004 } else if (tcf_proto_is_deleting(tp)) { 1005 /* 'deleting' flag is set and chain->filter_chain_lock was 1006 * unlocked, which means next pointer could be invalid. Restart 1007 * search. 1008 */ 1009 prio = tp->prio + 1; 1010 tp = tcf_chain_dereference(chain->filter_chain, chain); 1011 1012 for (; tp; tp = tcf_chain_dereference(tp->next, chain)) 1013 if (!tp->deleting && tp->prio >= prio) 1014 break; 1015 } else { 1016 tp = tcf_chain_dereference(tp->next, chain); 1017 } 1018 1019 if (tp) 1020 tcf_proto_get(tp); 1021 1022 mutex_unlock(&chain->filter_chain_lock); 1023 1024 return tp; 1025 } 1026 1027 /* Function to be used by all clients that want to iterate over all tp's on 1028 * chain. Users of this function must be tolerant to concurrent tp 1029 * insertion/deletion or ensure that no concurrent chain modification is 1030 * possible. Note that all netlink dump callbacks cannot guarantee to provide 1031 * consistent dump because rtnl lock is released each time skb is filled with 1032 * data and sent to user-space. 1033 */ 1034 1035 struct tcf_proto * 1036 tcf_get_next_proto(struct tcf_chain *chain, struct tcf_proto *tp, 1037 bool rtnl_held) 1038 { 1039 struct tcf_proto *tp_next = __tcf_get_next_proto(chain, tp); 1040 1041 if (tp) 1042 tcf_proto_put(tp, rtnl_held, NULL); 1043 1044 return tp_next; 1045 } 1046 EXPORT_SYMBOL(tcf_get_next_proto); 1047 1048 static void tcf_block_flush_all_chains(struct tcf_block *block, bool rtnl_held) 1049 { 1050 struct tcf_chain *chain; 1051 1052 /* Last reference to block. At this point chains cannot be added or 1053 * removed concurrently. 1054 */ 1055 for (chain = tcf_get_next_chain(block, NULL); 1056 chain; 1057 chain = tcf_get_next_chain(block, chain)) { 1058 tcf_chain_put_explicitly_created(chain); 1059 tcf_chain_flush(chain, rtnl_held); 1060 } 1061 } 1062 1063 /* Lookup Qdisc and increments its reference counter. 1064 * Set parent, if necessary. 1065 */ 1066 1067 static int __tcf_qdisc_find(struct net *net, struct Qdisc **q, 1068 u32 *parent, int ifindex, bool rtnl_held, 1069 struct netlink_ext_ack *extack) 1070 { 1071 const struct Qdisc_class_ops *cops; 1072 struct net_device *dev; 1073 int err = 0; 1074 1075 if (ifindex == TCM_IFINDEX_MAGIC_BLOCK) 1076 return 0; 1077 1078 rcu_read_lock(); 1079 1080 /* Find link */ 1081 dev = dev_get_by_index_rcu(net, ifindex); 1082 if (!dev) { 1083 rcu_read_unlock(); 1084 return -ENODEV; 1085 } 1086 1087 /* Find qdisc */ 1088 if (!*parent) { 1089 *q = dev->qdisc; 1090 *parent = (*q)->handle; 1091 } else { 1092 *q = qdisc_lookup_rcu(dev, TC_H_MAJ(*parent)); 1093 if (!*q) { 1094 NL_SET_ERR_MSG(extack, "Parent Qdisc doesn't exists"); 1095 err = -EINVAL; 1096 goto errout_rcu; 1097 } 1098 } 1099 1100 *q = qdisc_refcount_inc_nz(*q); 1101 if (!*q) { 1102 NL_SET_ERR_MSG(extack, "Parent Qdisc doesn't exists"); 1103 err = -EINVAL; 1104 goto errout_rcu; 1105 } 1106 1107 /* Is it classful? */ 1108 cops = (*q)->ops->cl_ops; 1109 if (!cops) { 1110 NL_SET_ERR_MSG(extack, "Qdisc not classful"); 1111 err = -EINVAL; 1112 goto errout_qdisc; 1113 } 1114 1115 if (!cops->tcf_block) { 1116 NL_SET_ERR_MSG(extack, "Class doesn't support blocks"); 1117 err = -EOPNOTSUPP; 1118 goto errout_qdisc; 1119 } 1120 1121 errout_rcu: 1122 /* At this point we know that qdisc is not noop_qdisc, 1123 * which means that qdisc holds a reference to net_device 1124 * and we hold a reference to qdisc, so it is safe to release 1125 * rcu read lock. 1126 */ 1127 rcu_read_unlock(); 1128 return err; 1129 1130 errout_qdisc: 1131 rcu_read_unlock(); 1132 1133 if (rtnl_held) 1134 qdisc_put(*q); 1135 else 1136 qdisc_put_unlocked(*q); 1137 *q = NULL; 1138 1139 return err; 1140 } 1141 1142 static int __tcf_qdisc_cl_find(struct Qdisc *q, u32 parent, unsigned long *cl, 1143 int ifindex, struct netlink_ext_ack *extack) 1144 { 1145 if (ifindex == TCM_IFINDEX_MAGIC_BLOCK) 1146 return 0; 1147 1148 /* Do we search for filter, attached to class? */ 1149 if (TC_H_MIN(parent)) { 1150 const struct Qdisc_class_ops *cops = q->ops->cl_ops; 1151 1152 *cl = cops->find(q, parent); 1153 if (*cl == 0) { 1154 NL_SET_ERR_MSG(extack, "Specified class doesn't exist"); 1155 return -ENOENT; 1156 } 1157 } 1158 1159 return 0; 1160 } 1161 1162 static struct tcf_block *__tcf_block_find(struct net *net, struct Qdisc *q, 1163 unsigned long cl, int ifindex, 1164 u32 block_index, 1165 struct netlink_ext_ack *extack) 1166 { 1167 struct tcf_block *block; 1168 1169 if (ifindex == TCM_IFINDEX_MAGIC_BLOCK) { 1170 block = tcf_block_refcnt_get(net, block_index); 1171 if (!block) { 1172 NL_SET_ERR_MSG(extack, "Block of given index was not found"); 1173 return ERR_PTR(-EINVAL); 1174 } 1175 } else { 1176 const struct Qdisc_class_ops *cops = q->ops->cl_ops; 1177 1178 block = cops->tcf_block(q, cl, extack); 1179 if (!block) 1180 return ERR_PTR(-EINVAL); 1181 1182 if (tcf_block_shared(block)) { 1183 NL_SET_ERR_MSG(extack, "This filter block is shared. Please use the block index to manipulate the filters"); 1184 return ERR_PTR(-EOPNOTSUPP); 1185 } 1186 1187 /* Always take reference to block in order to support execution 1188 * of rules update path of cls API without rtnl lock. Caller 1189 * must release block when it is finished using it. 'if' block 1190 * of this conditional obtain reference to block by calling 1191 * tcf_block_refcnt_get(). 1192 */ 1193 refcount_inc(&block->refcnt); 1194 } 1195 1196 return block; 1197 } 1198 1199 static void __tcf_block_put(struct tcf_block *block, struct Qdisc *q, 1200 struct tcf_block_ext_info *ei, bool rtnl_held) 1201 { 1202 if (refcount_dec_and_mutex_lock(&block->refcnt, &block->lock)) { 1203 /* Flushing/putting all chains will cause the block to be 1204 * deallocated when last chain is freed. However, if chain_list 1205 * is empty, block has to be manually deallocated. After block 1206 * reference counter reached 0, it is no longer possible to 1207 * increment it or add new chains to block. 1208 */ 1209 bool free_block = list_empty(&block->chain_list); 1210 1211 mutex_unlock(&block->lock); 1212 if (tcf_block_shared(block)) 1213 tcf_block_remove(block, block->net); 1214 1215 if (q) 1216 tcf_block_offload_unbind(block, q, ei); 1217 1218 if (free_block) 1219 tcf_block_destroy(block); 1220 else 1221 tcf_block_flush_all_chains(block, rtnl_held); 1222 } else if (q) { 1223 tcf_block_offload_unbind(block, q, ei); 1224 } 1225 } 1226 1227 static void tcf_block_refcnt_put(struct tcf_block *block, bool rtnl_held) 1228 { 1229 __tcf_block_put(block, NULL, NULL, rtnl_held); 1230 } 1231 1232 /* Find tcf block. 1233 * Set q, parent, cl when appropriate. 1234 */ 1235 1236 static struct tcf_block *tcf_block_find(struct net *net, struct Qdisc **q, 1237 u32 *parent, unsigned long *cl, 1238 int ifindex, u32 block_index, 1239 struct netlink_ext_ack *extack) 1240 { 1241 struct tcf_block *block; 1242 int err = 0; 1243 1244 ASSERT_RTNL(); 1245 1246 err = __tcf_qdisc_find(net, q, parent, ifindex, true, extack); 1247 if (err) 1248 goto errout; 1249 1250 err = __tcf_qdisc_cl_find(*q, *parent, cl, ifindex, extack); 1251 if (err) 1252 goto errout_qdisc; 1253 1254 block = __tcf_block_find(net, *q, *cl, ifindex, block_index, extack); 1255 if (IS_ERR(block)) { 1256 err = PTR_ERR(block); 1257 goto errout_qdisc; 1258 } 1259 1260 return block; 1261 1262 errout_qdisc: 1263 if (*q) 1264 qdisc_put(*q); 1265 errout: 1266 *q = NULL; 1267 return ERR_PTR(err); 1268 } 1269 1270 static void tcf_block_release(struct Qdisc *q, struct tcf_block *block, 1271 bool rtnl_held) 1272 { 1273 if (!IS_ERR_OR_NULL(block)) 1274 tcf_block_refcnt_put(block, rtnl_held); 1275 1276 if (q) { 1277 if (rtnl_held) 1278 qdisc_put(q); 1279 else 1280 qdisc_put_unlocked(q); 1281 } 1282 } 1283 1284 struct tcf_block_owner_item { 1285 struct list_head list; 1286 struct Qdisc *q; 1287 enum flow_block_binder_type binder_type; 1288 }; 1289 1290 static void 1291 tcf_block_owner_netif_keep_dst(struct tcf_block *block, 1292 struct Qdisc *q, 1293 enum flow_block_binder_type binder_type) 1294 { 1295 if (block->keep_dst && 1296 binder_type != FLOW_BLOCK_BINDER_TYPE_CLSACT_INGRESS && 1297 binder_type != FLOW_BLOCK_BINDER_TYPE_CLSACT_EGRESS) 1298 netif_keep_dst(qdisc_dev(q)); 1299 } 1300 1301 void tcf_block_netif_keep_dst(struct tcf_block *block) 1302 { 1303 struct tcf_block_owner_item *item; 1304 1305 block->keep_dst = true; 1306 list_for_each_entry(item, &block->owner_list, list) 1307 tcf_block_owner_netif_keep_dst(block, item->q, 1308 item->binder_type); 1309 } 1310 EXPORT_SYMBOL(tcf_block_netif_keep_dst); 1311 1312 static int tcf_block_owner_add(struct tcf_block *block, 1313 struct Qdisc *q, 1314 enum flow_block_binder_type binder_type) 1315 { 1316 struct tcf_block_owner_item *item; 1317 1318 item = kmalloc(sizeof(*item), GFP_KERNEL); 1319 if (!item) 1320 return -ENOMEM; 1321 item->q = q; 1322 item->binder_type = binder_type; 1323 list_add(&item->list, &block->owner_list); 1324 return 0; 1325 } 1326 1327 static void tcf_block_owner_del(struct tcf_block *block, 1328 struct Qdisc *q, 1329 enum flow_block_binder_type binder_type) 1330 { 1331 struct tcf_block_owner_item *item; 1332 1333 list_for_each_entry(item, &block->owner_list, list) { 1334 if (item->q == q && item->binder_type == binder_type) { 1335 list_del(&item->list); 1336 kfree(item); 1337 return; 1338 } 1339 } 1340 WARN_ON(1); 1341 } 1342 1343 int tcf_block_get_ext(struct tcf_block **p_block, struct Qdisc *q, 1344 struct tcf_block_ext_info *ei, 1345 struct netlink_ext_ack *extack) 1346 { 1347 struct net *net = qdisc_net(q); 1348 struct tcf_block *block = NULL; 1349 int err; 1350 1351 if (ei->block_index) 1352 /* block_index not 0 means the shared block is requested */ 1353 block = tcf_block_refcnt_get(net, ei->block_index); 1354 1355 if (!block) { 1356 block = tcf_block_create(net, q, ei->block_index, extack); 1357 if (IS_ERR(block)) 1358 return PTR_ERR(block); 1359 if (tcf_block_shared(block)) { 1360 err = tcf_block_insert(block, net, extack); 1361 if (err) 1362 goto err_block_insert; 1363 } 1364 } 1365 1366 err = tcf_block_owner_add(block, q, ei->binder_type); 1367 if (err) 1368 goto err_block_owner_add; 1369 1370 tcf_block_owner_netif_keep_dst(block, q, ei->binder_type); 1371 1372 err = tcf_chain0_head_change_cb_add(block, ei, extack); 1373 if (err) 1374 goto err_chain0_head_change_cb_add; 1375 1376 err = tcf_block_offload_bind(block, q, ei, extack); 1377 if (err) 1378 goto err_block_offload_bind; 1379 1380 *p_block = block; 1381 return 0; 1382 1383 err_block_offload_bind: 1384 tcf_chain0_head_change_cb_del(block, ei); 1385 err_chain0_head_change_cb_add: 1386 tcf_block_owner_del(block, q, ei->binder_type); 1387 err_block_owner_add: 1388 err_block_insert: 1389 tcf_block_refcnt_put(block, true); 1390 return err; 1391 } 1392 EXPORT_SYMBOL(tcf_block_get_ext); 1393 1394 static void tcf_chain_head_change_dflt(struct tcf_proto *tp_head, void *priv) 1395 { 1396 struct tcf_proto __rcu **p_filter_chain = priv; 1397 1398 rcu_assign_pointer(*p_filter_chain, tp_head); 1399 } 1400 1401 int tcf_block_get(struct tcf_block **p_block, 1402 struct tcf_proto __rcu **p_filter_chain, struct Qdisc *q, 1403 struct netlink_ext_ack *extack) 1404 { 1405 struct tcf_block_ext_info ei = { 1406 .chain_head_change = tcf_chain_head_change_dflt, 1407 .chain_head_change_priv = p_filter_chain, 1408 }; 1409 1410 WARN_ON(!p_filter_chain); 1411 return tcf_block_get_ext(p_block, q, &ei, extack); 1412 } 1413 EXPORT_SYMBOL(tcf_block_get); 1414 1415 /* XXX: Standalone actions are not allowed to jump to any chain, and bound 1416 * actions should be all removed after flushing. 1417 */ 1418 void tcf_block_put_ext(struct tcf_block *block, struct Qdisc *q, 1419 struct tcf_block_ext_info *ei) 1420 { 1421 if (!block) 1422 return; 1423 tcf_chain0_head_change_cb_del(block, ei); 1424 tcf_block_owner_del(block, q, ei->binder_type); 1425 1426 __tcf_block_put(block, q, ei, true); 1427 } 1428 EXPORT_SYMBOL(tcf_block_put_ext); 1429 1430 void tcf_block_put(struct tcf_block *block) 1431 { 1432 struct tcf_block_ext_info ei = {0, }; 1433 1434 if (!block) 1435 return; 1436 tcf_block_put_ext(block, block->q, &ei); 1437 } 1438 1439 EXPORT_SYMBOL(tcf_block_put); 1440 1441 static int 1442 tcf_block_playback_offloads(struct tcf_block *block, flow_setup_cb_t *cb, 1443 void *cb_priv, bool add, bool offload_in_use, 1444 struct netlink_ext_ack *extack) 1445 { 1446 struct tcf_chain *chain, *chain_prev; 1447 struct tcf_proto *tp, *tp_prev; 1448 int err; 1449 1450 lockdep_assert_held(&block->cb_lock); 1451 1452 for (chain = __tcf_get_next_chain(block, NULL); 1453 chain; 1454 chain_prev = chain, 1455 chain = __tcf_get_next_chain(block, chain), 1456 tcf_chain_put(chain_prev)) { 1457 for (tp = __tcf_get_next_proto(chain, NULL); tp; 1458 tp_prev = tp, 1459 tp = __tcf_get_next_proto(chain, tp), 1460 tcf_proto_put(tp_prev, true, NULL)) { 1461 if (tp->ops->reoffload) { 1462 err = tp->ops->reoffload(tp, add, cb, cb_priv, 1463 extack); 1464 if (err && add) 1465 goto err_playback_remove; 1466 } else if (add && offload_in_use) { 1467 err = -EOPNOTSUPP; 1468 NL_SET_ERR_MSG(extack, "Filter HW offload failed - classifier without re-offloading support"); 1469 goto err_playback_remove; 1470 } 1471 } 1472 } 1473 1474 return 0; 1475 1476 err_playback_remove: 1477 tcf_proto_put(tp, true, NULL); 1478 tcf_chain_put(chain); 1479 tcf_block_playback_offloads(block, cb, cb_priv, false, offload_in_use, 1480 extack); 1481 return err; 1482 } 1483 1484 static int tcf_block_bind(struct tcf_block *block, 1485 struct flow_block_offload *bo) 1486 { 1487 struct flow_block_cb *block_cb, *next; 1488 int err, i = 0; 1489 1490 lockdep_assert_held(&block->cb_lock); 1491 1492 list_for_each_entry(block_cb, &bo->cb_list, list) { 1493 err = tcf_block_playback_offloads(block, block_cb->cb, 1494 block_cb->cb_priv, true, 1495 tcf_block_offload_in_use(block), 1496 bo->extack); 1497 if (err) 1498 goto err_unroll; 1499 if (!bo->unlocked_driver_cb) 1500 block->lockeddevcnt++; 1501 1502 i++; 1503 } 1504 list_splice(&bo->cb_list, &block->flow_block.cb_list); 1505 1506 return 0; 1507 1508 err_unroll: 1509 list_for_each_entry_safe(block_cb, next, &bo->cb_list, list) { 1510 if (i-- > 0) { 1511 list_del(&block_cb->list); 1512 tcf_block_playback_offloads(block, block_cb->cb, 1513 block_cb->cb_priv, false, 1514 tcf_block_offload_in_use(block), 1515 NULL); 1516 if (!bo->unlocked_driver_cb) 1517 block->lockeddevcnt--; 1518 } 1519 flow_block_cb_free(block_cb); 1520 } 1521 1522 return err; 1523 } 1524 1525 static void tcf_block_unbind(struct tcf_block *block, 1526 struct flow_block_offload *bo) 1527 { 1528 struct flow_block_cb *block_cb, *next; 1529 1530 lockdep_assert_held(&block->cb_lock); 1531 1532 list_for_each_entry_safe(block_cb, next, &bo->cb_list, list) { 1533 tcf_block_playback_offloads(block, block_cb->cb, 1534 block_cb->cb_priv, false, 1535 tcf_block_offload_in_use(block), 1536 NULL); 1537 list_del(&block_cb->list); 1538 flow_block_cb_free(block_cb); 1539 if (!bo->unlocked_driver_cb) 1540 block->lockeddevcnt--; 1541 } 1542 } 1543 1544 static int tcf_block_setup(struct tcf_block *block, 1545 struct flow_block_offload *bo) 1546 { 1547 int err; 1548 1549 switch (bo->command) { 1550 case FLOW_BLOCK_BIND: 1551 err = tcf_block_bind(block, bo); 1552 break; 1553 case FLOW_BLOCK_UNBIND: 1554 err = 0; 1555 tcf_block_unbind(block, bo); 1556 break; 1557 default: 1558 WARN_ON_ONCE(1); 1559 err = -EOPNOTSUPP; 1560 } 1561 1562 return err; 1563 } 1564 1565 /* Main classifier routine: scans classifier chain attached 1566 * to this qdisc, (optionally) tests for protocol and asks 1567 * specific classifiers. 1568 */ 1569 int tcf_classify(struct sk_buff *skb, const struct tcf_proto *tp, 1570 struct tcf_result *res, bool compat_mode) 1571 { 1572 #ifdef CONFIG_NET_CLS_ACT 1573 const int max_reclassify_loop = 4; 1574 const struct tcf_proto *orig_tp = tp; 1575 const struct tcf_proto *first_tp; 1576 int limit = 0; 1577 1578 reclassify: 1579 #endif 1580 for (; tp; tp = rcu_dereference_bh(tp->next)) { 1581 __be16 protocol = tc_skb_protocol(skb); 1582 int err; 1583 1584 if (tp->protocol != protocol && 1585 tp->protocol != htons(ETH_P_ALL)) 1586 continue; 1587 1588 err = tp->classify(skb, tp, res); 1589 #ifdef CONFIG_NET_CLS_ACT 1590 if (unlikely(err == TC_ACT_RECLASSIFY && !compat_mode)) { 1591 first_tp = orig_tp; 1592 goto reset; 1593 } else if (unlikely(TC_ACT_EXT_CMP(err, TC_ACT_GOTO_CHAIN))) { 1594 first_tp = res->goto_tp; 1595 1596 #if IS_ENABLED(CONFIG_NET_TC_SKB_EXT) 1597 { 1598 struct tc_skb_ext *ext; 1599 1600 ext = skb_ext_add(skb, TC_SKB_EXT); 1601 if (WARN_ON_ONCE(!ext)) 1602 return TC_ACT_SHOT; 1603 1604 ext->chain = err & TC_ACT_EXT_VAL_MASK; 1605 } 1606 #endif 1607 goto reset; 1608 } 1609 #endif 1610 if (err >= 0) 1611 return err; 1612 } 1613 1614 return TC_ACT_UNSPEC; /* signal: continue lookup */ 1615 #ifdef CONFIG_NET_CLS_ACT 1616 reset: 1617 if (unlikely(limit++ >= max_reclassify_loop)) { 1618 net_notice_ratelimited("%u: reclassify loop, rule prio %u, protocol %02x\n", 1619 tp->chain->block->index, 1620 tp->prio & 0xffff, 1621 ntohs(tp->protocol)); 1622 return TC_ACT_SHOT; 1623 } 1624 1625 tp = first_tp; 1626 goto reclassify; 1627 #endif 1628 } 1629 EXPORT_SYMBOL(tcf_classify); 1630 1631 struct tcf_chain_info { 1632 struct tcf_proto __rcu **pprev; 1633 struct tcf_proto __rcu *next; 1634 }; 1635 1636 static struct tcf_proto *tcf_chain_tp_prev(struct tcf_chain *chain, 1637 struct tcf_chain_info *chain_info) 1638 { 1639 return tcf_chain_dereference(*chain_info->pprev, chain); 1640 } 1641 1642 static int tcf_chain_tp_insert(struct tcf_chain *chain, 1643 struct tcf_chain_info *chain_info, 1644 struct tcf_proto *tp) 1645 { 1646 if (chain->flushing) 1647 return -EAGAIN; 1648 1649 if (*chain_info->pprev == chain->filter_chain) 1650 tcf_chain0_head_change(chain, tp); 1651 tcf_proto_get(tp); 1652 RCU_INIT_POINTER(tp->next, tcf_chain_tp_prev(chain, chain_info)); 1653 rcu_assign_pointer(*chain_info->pprev, tp); 1654 1655 return 0; 1656 } 1657 1658 static void tcf_chain_tp_remove(struct tcf_chain *chain, 1659 struct tcf_chain_info *chain_info, 1660 struct tcf_proto *tp) 1661 { 1662 struct tcf_proto *next = tcf_chain_dereference(chain_info->next, chain); 1663 1664 tcf_proto_mark_delete(tp); 1665 if (tp == chain->filter_chain) 1666 tcf_chain0_head_change(chain, next); 1667 RCU_INIT_POINTER(*chain_info->pprev, next); 1668 } 1669 1670 static struct tcf_proto *tcf_chain_tp_find(struct tcf_chain *chain, 1671 struct tcf_chain_info *chain_info, 1672 u32 protocol, u32 prio, 1673 bool prio_allocate); 1674 1675 /* Try to insert new proto. 1676 * If proto with specified priority already exists, free new proto 1677 * and return existing one. 1678 */ 1679 1680 static struct tcf_proto *tcf_chain_tp_insert_unique(struct tcf_chain *chain, 1681 struct tcf_proto *tp_new, 1682 u32 protocol, u32 prio, 1683 bool rtnl_held) 1684 { 1685 struct tcf_chain_info chain_info; 1686 struct tcf_proto *tp; 1687 int err = 0; 1688 1689 mutex_lock(&chain->filter_chain_lock); 1690 1691 if (tcf_proto_exists_destroying(chain, tp_new)) { 1692 mutex_unlock(&chain->filter_chain_lock); 1693 tcf_proto_destroy(tp_new, rtnl_held, false, NULL); 1694 return ERR_PTR(-EAGAIN); 1695 } 1696 1697 tp = tcf_chain_tp_find(chain, &chain_info, 1698 protocol, prio, false); 1699 if (!tp) 1700 err = tcf_chain_tp_insert(chain, &chain_info, tp_new); 1701 mutex_unlock(&chain->filter_chain_lock); 1702 1703 if (tp) { 1704 tcf_proto_destroy(tp_new, rtnl_held, false, NULL); 1705 tp_new = tp; 1706 } else if (err) { 1707 tcf_proto_destroy(tp_new, rtnl_held, false, NULL); 1708 tp_new = ERR_PTR(err); 1709 } 1710 1711 return tp_new; 1712 } 1713 1714 static void tcf_chain_tp_delete_empty(struct tcf_chain *chain, 1715 struct tcf_proto *tp, bool rtnl_held, 1716 struct netlink_ext_ack *extack) 1717 { 1718 struct tcf_chain_info chain_info; 1719 struct tcf_proto *tp_iter; 1720 struct tcf_proto **pprev; 1721 struct tcf_proto *next; 1722 1723 mutex_lock(&chain->filter_chain_lock); 1724 1725 /* Atomically find and remove tp from chain. */ 1726 for (pprev = &chain->filter_chain; 1727 (tp_iter = tcf_chain_dereference(*pprev, chain)); 1728 pprev = &tp_iter->next) { 1729 if (tp_iter == tp) { 1730 chain_info.pprev = pprev; 1731 chain_info.next = tp_iter->next; 1732 WARN_ON(tp_iter->deleting); 1733 break; 1734 } 1735 } 1736 /* Verify that tp still exists and no new filters were inserted 1737 * concurrently. 1738 * Mark tp for deletion if it is empty. 1739 */ 1740 if (!tp_iter || !tcf_proto_check_delete(tp, rtnl_held)) { 1741 mutex_unlock(&chain->filter_chain_lock); 1742 return; 1743 } 1744 1745 tcf_proto_signal_destroying(chain, tp); 1746 next = tcf_chain_dereference(chain_info.next, chain); 1747 if (tp == chain->filter_chain) 1748 tcf_chain0_head_change(chain, next); 1749 RCU_INIT_POINTER(*chain_info.pprev, next); 1750 mutex_unlock(&chain->filter_chain_lock); 1751 1752 tcf_proto_put(tp, rtnl_held, extack); 1753 } 1754 1755 static struct tcf_proto *tcf_chain_tp_find(struct tcf_chain *chain, 1756 struct tcf_chain_info *chain_info, 1757 u32 protocol, u32 prio, 1758 bool prio_allocate) 1759 { 1760 struct tcf_proto **pprev; 1761 struct tcf_proto *tp; 1762 1763 /* Check the chain for existence of proto-tcf with this priority */ 1764 for (pprev = &chain->filter_chain; 1765 (tp = tcf_chain_dereference(*pprev, chain)); 1766 pprev = &tp->next) { 1767 if (tp->prio >= prio) { 1768 if (tp->prio == prio) { 1769 if (prio_allocate || 1770 (tp->protocol != protocol && protocol)) 1771 return ERR_PTR(-EINVAL); 1772 } else { 1773 tp = NULL; 1774 } 1775 break; 1776 } 1777 } 1778 chain_info->pprev = pprev; 1779 if (tp) { 1780 chain_info->next = tp->next; 1781 tcf_proto_get(tp); 1782 } else { 1783 chain_info->next = NULL; 1784 } 1785 return tp; 1786 } 1787 1788 static int tcf_fill_node(struct net *net, struct sk_buff *skb, 1789 struct tcf_proto *tp, struct tcf_block *block, 1790 struct Qdisc *q, u32 parent, void *fh, 1791 u32 portid, u32 seq, u16 flags, int event, 1792 bool rtnl_held) 1793 { 1794 struct tcmsg *tcm; 1795 struct nlmsghdr *nlh; 1796 unsigned char *b = skb_tail_pointer(skb); 1797 1798 nlh = nlmsg_put(skb, portid, seq, event, sizeof(*tcm), flags); 1799 if (!nlh) 1800 goto out_nlmsg_trim; 1801 tcm = nlmsg_data(nlh); 1802 tcm->tcm_family = AF_UNSPEC; 1803 tcm->tcm__pad1 = 0; 1804 tcm->tcm__pad2 = 0; 1805 if (q) { 1806 tcm->tcm_ifindex = qdisc_dev(q)->ifindex; 1807 tcm->tcm_parent = parent; 1808 } else { 1809 tcm->tcm_ifindex = TCM_IFINDEX_MAGIC_BLOCK; 1810 tcm->tcm_block_index = block->index; 1811 } 1812 tcm->tcm_info = TC_H_MAKE(tp->prio, tp->protocol); 1813 if (nla_put_string(skb, TCA_KIND, tp->ops->kind)) 1814 goto nla_put_failure; 1815 if (nla_put_u32(skb, TCA_CHAIN, tp->chain->index)) 1816 goto nla_put_failure; 1817 if (!fh) { 1818 tcm->tcm_handle = 0; 1819 } else { 1820 if (tp->ops->dump && 1821 tp->ops->dump(net, tp, fh, skb, tcm, rtnl_held) < 0) 1822 goto nla_put_failure; 1823 } 1824 nlh->nlmsg_len = skb_tail_pointer(skb) - b; 1825 return skb->len; 1826 1827 out_nlmsg_trim: 1828 nla_put_failure: 1829 nlmsg_trim(skb, b); 1830 return -1; 1831 } 1832 1833 static int tfilter_notify(struct net *net, struct sk_buff *oskb, 1834 struct nlmsghdr *n, struct tcf_proto *tp, 1835 struct tcf_block *block, struct Qdisc *q, 1836 u32 parent, void *fh, int event, bool unicast, 1837 bool rtnl_held) 1838 { 1839 struct sk_buff *skb; 1840 u32 portid = oskb ? NETLINK_CB(oskb).portid : 0; 1841 int err = 0; 1842 1843 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL); 1844 if (!skb) 1845 return -ENOBUFS; 1846 1847 if (tcf_fill_node(net, skb, tp, block, q, parent, fh, portid, 1848 n->nlmsg_seq, n->nlmsg_flags, event, 1849 rtnl_held) <= 0) { 1850 kfree_skb(skb); 1851 return -EINVAL; 1852 } 1853 1854 if (unicast) 1855 err = netlink_unicast(net->rtnl, skb, portid, MSG_DONTWAIT); 1856 else 1857 err = rtnetlink_send(skb, net, portid, RTNLGRP_TC, 1858 n->nlmsg_flags & NLM_F_ECHO); 1859 1860 if (err > 0) 1861 err = 0; 1862 return err; 1863 } 1864 1865 static int tfilter_del_notify(struct net *net, struct sk_buff *oskb, 1866 struct nlmsghdr *n, struct tcf_proto *tp, 1867 struct tcf_block *block, struct Qdisc *q, 1868 u32 parent, void *fh, bool unicast, bool *last, 1869 bool rtnl_held, struct netlink_ext_ack *extack) 1870 { 1871 struct sk_buff *skb; 1872 u32 portid = oskb ? NETLINK_CB(oskb).portid : 0; 1873 int err; 1874 1875 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL); 1876 if (!skb) 1877 return -ENOBUFS; 1878 1879 if (tcf_fill_node(net, skb, tp, block, q, parent, fh, portid, 1880 n->nlmsg_seq, n->nlmsg_flags, RTM_DELTFILTER, 1881 rtnl_held) <= 0) { 1882 NL_SET_ERR_MSG(extack, "Failed to build del event notification"); 1883 kfree_skb(skb); 1884 return -EINVAL; 1885 } 1886 1887 err = tp->ops->delete(tp, fh, last, rtnl_held, extack); 1888 if (err) { 1889 kfree_skb(skb); 1890 return err; 1891 } 1892 1893 if (unicast) 1894 err = netlink_unicast(net->rtnl, skb, portid, MSG_DONTWAIT); 1895 else 1896 err = rtnetlink_send(skb, net, portid, RTNLGRP_TC, 1897 n->nlmsg_flags & NLM_F_ECHO); 1898 if (err < 0) 1899 NL_SET_ERR_MSG(extack, "Failed to send filter delete notification"); 1900 1901 if (err > 0) 1902 err = 0; 1903 return err; 1904 } 1905 1906 static void tfilter_notify_chain(struct net *net, struct sk_buff *oskb, 1907 struct tcf_block *block, struct Qdisc *q, 1908 u32 parent, struct nlmsghdr *n, 1909 struct tcf_chain *chain, int event, 1910 bool rtnl_held) 1911 { 1912 struct tcf_proto *tp; 1913 1914 for (tp = tcf_get_next_proto(chain, NULL, rtnl_held); 1915 tp; tp = tcf_get_next_proto(chain, tp, rtnl_held)) 1916 tfilter_notify(net, oskb, n, tp, block, 1917 q, parent, NULL, event, false, rtnl_held); 1918 } 1919 1920 static void tfilter_put(struct tcf_proto *tp, void *fh) 1921 { 1922 if (tp->ops->put && fh) 1923 tp->ops->put(tp, fh); 1924 } 1925 1926 static int tc_new_tfilter(struct sk_buff *skb, struct nlmsghdr *n, 1927 struct netlink_ext_ack *extack) 1928 { 1929 struct net *net = sock_net(skb->sk); 1930 struct nlattr *tca[TCA_MAX + 1]; 1931 char name[IFNAMSIZ]; 1932 struct tcmsg *t; 1933 u32 protocol; 1934 u32 prio; 1935 bool prio_allocate; 1936 u32 parent; 1937 u32 chain_index; 1938 struct Qdisc *q = NULL; 1939 struct tcf_chain_info chain_info; 1940 struct tcf_chain *chain = NULL; 1941 struct tcf_block *block; 1942 struct tcf_proto *tp; 1943 unsigned long cl; 1944 void *fh; 1945 int err; 1946 int tp_created; 1947 bool rtnl_held = false; 1948 1949 if (!netlink_ns_capable(skb, net->user_ns, CAP_NET_ADMIN)) 1950 return -EPERM; 1951 1952 replay: 1953 tp_created = 0; 1954 1955 err = nlmsg_parse_deprecated(n, sizeof(*t), tca, TCA_MAX, 1956 rtm_tca_policy, extack); 1957 if (err < 0) 1958 return err; 1959 1960 t = nlmsg_data(n); 1961 protocol = TC_H_MIN(t->tcm_info); 1962 prio = TC_H_MAJ(t->tcm_info); 1963 prio_allocate = false; 1964 parent = t->tcm_parent; 1965 tp = NULL; 1966 cl = 0; 1967 block = NULL; 1968 1969 if (prio == 0) { 1970 /* If no priority is provided by the user, 1971 * we allocate one. 1972 */ 1973 if (n->nlmsg_flags & NLM_F_CREATE) { 1974 prio = TC_H_MAKE(0x80000000U, 0U); 1975 prio_allocate = true; 1976 } else { 1977 NL_SET_ERR_MSG(extack, "Invalid filter command with priority of zero"); 1978 return -ENOENT; 1979 } 1980 } 1981 1982 /* Find head of filter chain. */ 1983 1984 err = __tcf_qdisc_find(net, &q, &parent, t->tcm_ifindex, false, extack); 1985 if (err) 1986 return err; 1987 1988 if (tcf_proto_check_kind(tca[TCA_KIND], name)) { 1989 NL_SET_ERR_MSG(extack, "Specified TC filter name too long"); 1990 err = -EINVAL; 1991 goto errout; 1992 } 1993 1994 /* Take rtnl mutex if rtnl_held was set to true on previous iteration, 1995 * block is shared (no qdisc found), qdisc is not unlocked, classifier 1996 * type is not specified, classifier is not unlocked. 1997 */ 1998 if (rtnl_held || 1999 (q && !(q->ops->cl_ops->flags & QDISC_CLASS_OPS_DOIT_UNLOCKED)) || 2000 !tcf_proto_is_unlocked(name)) { 2001 rtnl_held = true; 2002 rtnl_lock(); 2003 } 2004 2005 err = __tcf_qdisc_cl_find(q, parent, &cl, t->tcm_ifindex, extack); 2006 if (err) 2007 goto errout; 2008 2009 block = __tcf_block_find(net, q, cl, t->tcm_ifindex, t->tcm_block_index, 2010 extack); 2011 if (IS_ERR(block)) { 2012 err = PTR_ERR(block); 2013 goto errout; 2014 } 2015 2016 chain_index = tca[TCA_CHAIN] ? nla_get_u32(tca[TCA_CHAIN]) : 0; 2017 if (chain_index > TC_ACT_EXT_VAL_MASK) { 2018 NL_SET_ERR_MSG(extack, "Specified chain index exceeds upper limit"); 2019 err = -EINVAL; 2020 goto errout; 2021 } 2022 chain = tcf_chain_get(block, chain_index, true); 2023 if (!chain) { 2024 NL_SET_ERR_MSG(extack, "Cannot create specified filter chain"); 2025 err = -ENOMEM; 2026 goto errout; 2027 } 2028 2029 mutex_lock(&chain->filter_chain_lock); 2030 tp = tcf_chain_tp_find(chain, &chain_info, protocol, 2031 prio, prio_allocate); 2032 if (IS_ERR(tp)) { 2033 NL_SET_ERR_MSG(extack, "Filter with specified priority/protocol not found"); 2034 err = PTR_ERR(tp); 2035 goto errout_locked; 2036 } 2037 2038 if (tp == NULL) { 2039 struct tcf_proto *tp_new = NULL; 2040 2041 if (chain->flushing) { 2042 err = -EAGAIN; 2043 goto errout_locked; 2044 } 2045 2046 /* Proto-tcf does not exist, create new one */ 2047 2048 if (tca[TCA_KIND] == NULL || !protocol) { 2049 NL_SET_ERR_MSG(extack, "Filter kind and protocol must be specified"); 2050 err = -EINVAL; 2051 goto errout_locked; 2052 } 2053 2054 if (!(n->nlmsg_flags & NLM_F_CREATE)) { 2055 NL_SET_ERR_MSG(extack, "Need both RTM_NEWTFILTER and NLM_F_CREATE to create a new filter"); 2056 err = -ENOENT; 2057 goto errout_locked; 2058 } 2059 2060 if (prio_allocate) 2061 prio = tcf_auto_prio(tcf_chain_tp_prev(chain, 2062 &chain_info)); 2063 2064 mutex_unlock(&chain->filter_chain_lock); 2065 tp_new = tcf_proto_create(nla_data(tca[TCA_KIND]), 2066 protocol, prio, chain, rtnl_held, 2067 extack); 2068 if (IS_ERR(tp_new)) { 2069 err = PTR_ERR(tp_new); 2070 goto errout_tp; 2071 } 2072 2073 tp_created = 1; 2074 tp = tcf_chain_tp_insert_unique(chain, tp_new, protocol, prio, 2075 rtnl_held); 2076 if (IS_ERR(tp)) { 2077 err = PTR_ERR(tp); 2078 goto errout_tp; 2079 } 2080 } else { 2081 mutex_unlock(&chain->filter_chain_lock); 2082 } 2083 2084 if (tca[TCA_KIND] && nla_strcmp(tca[TCA_KIND], tp->ops->kind)) { 2085 NL_SET_ERR_MSG(extack, "Specified filter kind does not match existing one"); 2086 err = -EINVAL; 2087 goto errout; 2088 } 2089 2090 fh = tp->ops->get(tp, t->tcm_handle); 2091 2092 if (!fh) { 2093 if (!(n->nlmsg_flags & NLM_F_CREATE)) { 2094 NL_SET_ERR_MSG(extack, "Need both RTM_NEWTFILTER and NLM_F_CREATE to create a new filter"); 2095 err = -ENOENT; 2096 goto errout; 2097 } 2098 } else if (n->nlmsg_flags & NLM_F_EXCL) { 2099 tfilter_put(tp, fh); 2100 NL_SET_ERR_MSG(extack, "Filter already exists"); 2101 err = -EEXIST; 2102 goto errout; 2103 } 2104 2105 if (chain->tmplt_ops && chain->tmplt_ops != tp->ops) { 2106 NL_SET_ERR_MSG(extack, "Chain template is set to a different filter kind"); 2107 err = -EINVAL; 2108 goto errout; 2109 } 2110 2111 err = tp->ops->change(net, skb, tp, cl, t->tcm_handle, tca, &fh, 2112 n->nlmsg_flags & NLM_F_CREATE ? TCA_ACT_NOREPLACE : TCA_ACT_REPLACE, 2113 rtnl_held, extack); 2114 if (err == 0) { 2115 tfilter_notify(net, skb, n, tp, block, q, parent, fh, 2116 RTM_NEWTFILTER, false, rtnl_held); 2117 tfilter_put(tp, fh); 2118 /* q pointer is NULL for shared blocks */ 2119 if (q) 2120 q->flags &= ~TCQ_F_CAN_BYPASS; 2121 } 2122 2123 errout: 2124 if (err && tp_created) 2125 tcf_chain_tp_delete_empty(chain, tp, rtnl_held, NULL); 2126 errout_tp: 2127 if (chain) { 2128 if (tp && !IS_ERR(tp)) 2129 tcf_proto_put(tp, rtnl_held, NULL); 2130 if (!tp_created) 2131 tcf_chain_put(chain); 2132 } 2133 tcf_block_release(q, block, rtnl_held); 2134 2135 if (rtnl_held) 2136 rtnl_unlock(); 2137 2138 if (err == -EAGAIN) { 2139 /* Take rtnl lock in case EAGAIN is caused by concurrent flush 2140 * of target chain. 2141 */ 2142 rtnl_held = true; 2143 /* Replay the request. */ 2144 goto replay; 2145 } 2146 return err; 2147 2148 errout_locked: 2149 mutex_unlock(&chain->filter_chain_lock); 2150 goto errout; 2151 } 2152 2153 static int tc_del_tfilter(struct sk_buff *skb, struct nlmsghdr *n, 2154 struct netlink_ext_ack *extack) 2155 { 2156 struct net *net = sock_net(skb->sk); 2157 struct nlattr *tca[TCA_MAX + 1]; 2158 char name[IFNAMSIZ]; 2159 struct tcmsg *t; 2160 u32 protocol; 2161 u32 prio; 2162 u32 parent; 2163 u32 chain_index; 2164 struct Qdisc *q = NULL; 2165 struct tcf_chain_info chain_info; 2166 struct tcf_chain *chain = NULL; 2167 struct tcf_block *block = NULL; 2168 struct tcf_proto *tp = NULL; 2169 unsigned long cl = 0; 2170 void *fh = NULL; 2171 int err; 2172 bool rtnl_held = false; 2173 2174 if (!netlink_ns_capable(skb, net->user_ns, CAP_NET_ADMIN)) 2175 return -EPERM; 2176 2177 err = nlmsg_parse_deprecated(n, sizeof(*t), tca, TCA_MAX, 2178 rtm_tca_policy, extack); 2179 if (err < 0) 2180 return err; 2181 2182 t = nlmsg_data(n); 2183 protocol = TC_H_MIN(t->tcm_info); 2184 prio = TC_H_MAJ(t->tcm_info); 2185 parent = t->tcm_parent; 2186 2187 if (prio == 0 && (protocol || t->tcm_handle || tca[TCA_KIND])) { 2188 NL_SET_ERR_MSG(extack, "Cannot flush filters with protocol, handle or kind set"); 2189 return -ENOENT; 2190 } 2191 2192 /* Find head of filter chain. */ 2193 2194 err = __tcf_qdisc_find(net, &q, &parent, t->tcm_ifindex, false, extack); 2195 if (err) 2196 return err; 2197 2198 if (tcf_proto_check_kind(tca[TCA_KIND], name)) { 2199 NL_SET_ERR_MSG(extack, "Specified TC filter name too long"); 2200 err = -EINVAL; 2201 goto errout; 2202 } 2203 /* Take rtnl mutex if flushing whole chain, block is shared (no qdisc 2204 * found), qdisc is not unlocked, classifier type is not specified, 2205 * classifier is not unlocked. 2206 */ 2207 if (!prio || 2208 (q && !(q->ops->cl_ops->flags & QDISC_CLASS_OPS_DOIT_UNLOCKED)) || 2209 !tcf_proto_is_unlocked(name)) { 2210 rtnl_held = true; 2211 rtnl_lock(); 2212 } 2213 2214 err = __tcf_qdisc_cl_find(q, parent, &cl, t->tcm_ifindex, extack); 2215 if (err) 2216 goto errout; 2217 2218 block = __tcf_block_find(net, q, cl, t->tcm_ifindex, t->tcm_block_index, 2219 extack); 2220 if (IS_ERR(block)) { 2221 err = PTR_ERR(block); 2222 goto errout; 2223 } 2224 2225 chain_index = tca[TCA_CHAIN] ? nla_get_u32(tca[TCA_CHAIN]) : 0; 2226 if (chain_index > TC_ACT_EXT_VAL_MASK) { 2227 NL_SET_ERR_MSG(extack, "Specified chain index exceeds upper limit"); 2228 err = -EINVAL; 2229 goto errout; 2230 } 2231 chain = tcf_chain_get(block, chain_index, false); 2232 if (!chain) { 2233 /* User requested flush on non-existent chain. Nothing to do, 2234 * so just return success. 2235 */ 2236 if (prio == 0) { 2237 err = 0; 2238 goto errout; 2239 } 2240 NL_SET_ERR_MSG(extack, "Cannot find specified filter chain"); 2241 err = -ENOENT; 2242 goto errout; 2243 } 2244 2245 if (prio == 0) { 2246 tfilter_notify_chain(net, skb, block, q, parent, n, 2247 chain, RTM_DELTFILTER, rtnl_held); 2248 tcf_chain_flush(chain, rtnl_held); 2249 err = 0; 2250 goto errout; 2251 } 2252 2253 mutex_lock(&chain->filter_chain_lock); 2254 tp = tcf_chain_tp_find(chain, &chain_info, protocol, 2255 prio, false); 2256 if (!tp || IS_ERR(tp)) { 2257 NL_SET_ERR_MSG(extack, "Filter with specified priority/protocol not found"); 2258 err = tp ? PTR_ERR(tp) : -ENOENT; 2259 goto errout_locked; 2260 } else if (tca[TCA_KIND] && nla_strcmp(tca[TCA_KIND], tp->ops->kind)) { 2261 NL_SET_ERR_MSG(extack, "Specified filter kind does not match existing one"); 2262 err = -EINVAL; 2263 goto errout_locked; 2264 } else if (t->tcm_handle == 0) { 2265 tcf_proto_signal_destroying(chain, tp); 2266 tcf_chain_tp_remove(chain, &chain_info, tp); 2267 mutex_unlock(&chain->filter_chain_lock); 2268 2269 tcf_proto_put(tp, rtnl_held, NULL); 2270 tfilter_notify(net, skb, n, tp, block, q, parent, fh, 2271 RTM_DELTFILTER, false, rtnl_held); 2272 err = 0; 2273 goto errout; 2274 } 2275 mutex_unlock(&chain->filter_chain_lock); 2276 2277 fh = tp->ops->get(tp, t->tcm_handle); 2278 2279 if (!fh) { 2280 NL_SET_ERR_MSG(extack, "Specified filter handle not found"); 2281 err = -ENOENT; 2282 } else { 2283 bool last; 2284 2285 err = tfilter_del_notify(net, skb, n, tp, block, 2286 q, parent, fh, false, &last, 2287 rtnl_held, extack); 2288 2289 if (err) 2290 goto errout; 2291 if (last) 2292 tcf_chain_tp_delete_empty(chain, tp, rtnl_held, extack); 2293 } 2294 2295 errout: 2296 if (chain) { 2297 if (tp && !IS_ERR(tp)) 2298 tcf_proto_put(tp, rtnl_held, NULL); 2299 tcf_chain_put(chain); 2300 } 2301 tcf_block_release(q, block, rtnl_held); 2302 2303 if (rtnl_held) 2304 rtnl_unlock(); 2305 2306 return err; 2307 2308 errout_locked: 2309 mutex_unlock(&chain->filter_chain_lock); 2310 goto errout; 2311 } 2312 2313 static int tc_get_tfilter(struct sk_buff *skb, struct nlmsghdr *n, 2314 struct netlink_ext_ack *extack) 2315 { 2316 struct net *net = sock_net(skb->sk); 2317 struct nlattr *tca[TCA_MAX + 1]; 2318 char name[IFNAMSIZ]; 2319 struct tcmsg *t; 2320 u32 protocol; 2321 u32 prio; 2322 u32 parent; 2323 u32 chain_index; 2324 struct Qdisc *q = NULL; 2325 struct tcf_chain_info chain_info; 2326 struct tcf_chain *chain = NULL; 2327 struct tcf_block *block = NULL; 2328 struct tcf_proto *tp = NULL; 2329 unsigned long cl = 0; 2330 void *fh = NULL; 2331 int err; 2332 bool rtnl_held = false; 2333 2334 err = nlmsg_parse_deprecated(n, sizeof(*t), tca, TCA_MAX, 2335 rtm_tca_policy, extack); 2336 if (err < 0) 2337 return err; 2338 2339 t = nlmsg_data(n); 2340 protocol = TC_H_MIN(t->tcm_info); 2341 prio = TC_H_MAJ(t->tcm_info); 2342 parent = t->tcm_parent; 2343 2344 if (prio == 0) { 2345 NL_SET_ERR_MSG(extack, "Invalid filter command with priority of zero"); 2346 return -ENOENT; 2347 } 2348 2349 /* Find head of filter chain. */ 2350 2351 err = __tcf_qdisc_find(net, &q, &parent, t->tcm_ifindex, false, extack); 2352 if (err) 2353 return err; 2354 2355 if (tcf_proto_check_kind(tca[TCA_KIND], name)) { 2356 NL_SET_ERR_MSG(extack, "Specified TC filter name too long"); 2357 err = -EINVAL; 2358 goto errout; 2359 } 2360 /* Take rtnl mutex if block is shared (no qdisc found), qdisc is not 2361 * unlocked, classifier type is not specified, classifier is not 2362 * unlocked. 2363 */ 2364 if ((q && !(q->ops->cl_ops->flags & QDISC_CLASS_OPS_DOIT_UNLOCKED)) || 2365 !tcf_proto_is_unlocked(name)) { 2366 rtnl_held = true; 2367 rtnl_lock(); 2368 } 2369 2370 err = __tcf_qdisc_cl_find(q, parent, &cl, t->tcm_ifindex, extack); 2371 if (err) 2372 goto errout; 2373 2374 block = __tcf_block_find(net, q, cl, t->tcm_ifindex, t->tcm_block_index, 2375 extack); 2376 if (IS_ERR(block)) { 2377 err = PTR_ERR(block); 2378 goto errout; 2379 } 2380 2381 chain_index = tca[TCA_CHAIN] ? nla_get_u32(tca[TCA_CHAIN]) : 0; 2382 if (chain_index > TC_ACT_EXT_VAL_MASK) { 2383 NL_SET_ERR_MSG(extack, "Specified chain index exceeds upper limit"); 2384 err = -EINVAL; 2385 goto errout; 2386 } 2387 chain = tcf_chain_get(block, chain_index, false); 2388 if (!chain) { 2389 NL_SET_ERR_MSG(extack, "Cannot find specified filter chain"); 2390 err = -EINVAL; 2391 goto errout; 2392 } 2393 2394 mutex_lock(&chain->filter_chain_lock); 2395 tp = tcf_chain_tp_find(chain, &chain_info, protocol, 2396 prio, false); 2397 mutex_unlock(&chain->filter_chain_lock); 2398 if (!tp || IS_ERR(tp)) { 2399 NL_SET_ERR_MSG(extack, "Filter with specified priority/protocol not found"); 2400 err = tp ? PTR_ERR(tp) : -ENOENT; 2401 goto errout; 2402 } else if (tca[TCA_KIND] && nla_strcmp(tca[TCA_KIND], tp->ops->kind)) { 2403 NL_SET_ERR_MSG(extack, "Specified filter kind does not match existing one"); 2404 err = -EINVAL; 2405 goto errout; 2406 } 2407 2408 fh = tp->ops->get(tp, t->tcm_handle); 2409 2410 if (!fh) { 2411 NL_SET_ERR_MSG(extack, "Specified filter handle not found"); 2412 err = -ENOENT; 2413 } else { 2414 err = tfilter_notify(net, skb, n, tp, block, q, parent, 2415 fh, RTM_NEWTFILTER, true, rtnl_held); 2416 if (err < 0) 2417 NL_SET_ERR_MSG(extack, "Failed to send filter notify message"); 2418 } 2419 2420 tfilter_put(tp, fh); 2421 errout: 2422 if (chain) { 2423 if (tp && !IS_ERR(tp)) 2424 tcf_proto_put(tp, rtnl_held, NULL); 2425 tcf_chain_put(chain); 2426 } 2427 tcf_block_release(q, block, rtnl_held); 2428 2429 if (rtnl_held) 2430 rtnl_unlock(); 2431 2432 return err; 2433 } 2434 2435 struct tcf_dump_args { 2436 struct tcf_walker w; 2437 struct sk_buff *skb; 2438 struct netlink_callback *cb; 2439 struct tcf_block *block; 2440 struct Qdisc *q; 2441 u32 parent; 2442 }; 2443 2444 static int tcf_node_dump(struct tcf_proto *tp, void *n, struct tcf_walker *arg) 2445 { 2446 struct tcf_dump_args *a = (void *)arg; 2447 struct net *net = sock_net(a->skb->sk); 2448 2449 return tcf_fill_node(net, a->skb, tp, a->block, a->q, a->parent, 2450 n, NETLINK_CB(a->cb->skb).portid, 2451 a->cb->nlh->nlmsg_seq, NLM_F_MULTI, 2452 RTM_NEWTFILTER, true); 2453 } 2454 2455 static bool tcf_chain_dump(struct tcf_chain *chain, struct Qdisc *q, u32 parent, 2456 struct sk_buff *skb, struct netlink_callback *cb, 2457 long index_start, long *p_index) 2458 { 2459 struct net *net = sock_net(skb->sk); 2460 struct tcf_block *block = chain->block; 2461 struct tcmsg *tcm = nlmsg_data(cb->nlh); 2462 struct tcf_proto *tp, *tp_prev; 2463 struct tcf_dump_args arg; 2464 2465 for (tp = __tcf_get_next_proto(chain, NULL); 2466 tp; 2467 tp_prev = tp, 2468 tp = __tcf_get_next_proto(chain, tp), 2469 tcf_proto_put(tp_prev, true, NULL), 2470 (*p_index)++) { 2471 if (*p_index < index_start) 2472 continue; 2473 if (TC_H_MAJ(tcm->tcm_info) && 2474 TC_H_MAJ(tcm->tcm_info) != tp->prio) 2475 continue; 2476 if (TC_H_MIN(tcm->tcm_info) && 2477 TC_H_MIN(tcm->tcm_info) != tp->protocol) 2478 continue; 2479 if (*p_index > index_start) 2480 memset(&cb->args[1], 0, 2481 sizeof(cb->args) - sizeof(cb->args[0])); 2482 if (cb->args[1] == 0) { 2483 if (tcf_fill_node(net, skb, tp, block, q, parent, NULL, 2484 NETLINK_CB(cb->skb).portid, 2485 cb->nlh->nlmsg_seq, NLM_F_MULTI, 2486 RTM_NEWTFILTER, true) <= 0) 2487 goto errout; 2488 cb->args[1] = 1; 2489 } 2490 if (!tp->ops->walk) 2491 continue; 2492 arg.w.fn = tcf_node_dump; 2493 arg.skb = skb; 2494 arg.cb = cb; 2495 arg.block = block; 2496 arg.q = q; 2497 arg.parent = parent; 2498 arg.w.stop = 0; 2499 arg.w.skip = cb->args[1] - 1; 2500 arg.w.count = 0; 2501 arg.w.cookie = cb->args[2]; 2502 tp->ops->walk(tp, &arg.w, true); 2503 cb->args[2] = arg.w.cookie; 2504 cb->args[1] = arg.w.count + 1; 2505 if (arg.w.stop) 2506 goto errout; 2507 } 2508 return true; 2509 2510 errout: 2511 tcf_proto_put(tp, true, NULL); 2512 return false; 2513 } 2514 2515 /* called with RTNL */ 2516 static int tc_dump_tfilter(struct sk_buff *skb, struct netlink_callback *cb) 2517 { 2518 struct tcf_chain *chain, *chain_prev; 2519 struct net *net = sock_net(skb->sk); 2520 struct nlattr *tca[TCA_MAX + 1]; 2521 struct Qdisc *q = NULL; 2522 struct tcf_block *block; 2523 struct tcmsg *tcm = nlmsg_data(cb->nlh); 2524 long index_start; 2525 long index; 2526 u32 parent; 2527 int err; 2528 2529 if (nlmsg_len(cb->nlh) < sizeof(*tcm)) 2530 return skb->len; 2531 2532 err = nlmsg_parse_deprecated(cb->nlh, sizeof(*tcm), tca, TCA_MAX, 2533 NULL, cb->extack); 2534 if (err) 2535 return err; 2536 2537 if (tcm->tcm_ifindex == TCM_IFINDEX_MAGIC_BLOCK) { 2538 block = tcf_block_refcnt_get(net, tcm->tcm_block_index); 2539 if (!block) 2540 goto out; 2541 /* If we work with block index, q is NULL and parent value 2542 * will never be used in the following code. The check 2543 * in tcf_fill_node prevents it. However, compiler does not 2544 * see that far, so set parent to zero to silence the warning 2545 * about parent being uninitialized. 2546 */ 2547 parent = 0; 2548 } else { 2549 const struct Qdisc_class_ops *cops; 2550 struct net_device *dev; 2551 unsigned long cl = 0; 2552 2553 dev = __dev_get_by_index(net, tcm->tcm_ifindex); 2554 if (!dev) 2555 return skb->len; 2556 2557 parent = tcm->tcm_parent; 2558 if (!parent) { 2559 q = dev->qdisc; 2560 parent = q->handle; 2561 } else { 2562 q = qdisc_lookup(dev, TC_H_MAJ(tcm->tcm_parent)); 2563 } 2564 if (!q) 2565 goto out; 2566 cops = q->ops->cl_ops; 2567 if (!cops) 2568 goto out; 2569 if (!cops->tcf_block) 2570 goto out; 2571 if (TC_H_MIN(tcm->tcm_parent)) { 2572 cl = cops->find(q, tcm->tcm_parent); 2573 if (cl == 0) 2574 goto out; 2575 } 2576 block = cops->tcf_block(q, cl, NULL); 2577 if (!block) 2578 goto out; 2579 if (tcf_block_shared(block)) 2580 q = NULL; 2581 } 2582 2583 index_start = cb->args[0]; 2584 index = 0; 2585 2586 for (chain = __tcf_get_next_chain(block, NULL); 2587 chain; 2588 chain_prev = chain, 2589 chain = __tcf_get_next_chain(block, chain), 2590 tcf_chain_put(chain_prev)) { 2591 if (tca[TCA_CHAIN] && 2592 nla_get_u32(tca[TCA_CHAIN]) != chain->index) 2593 continue; 2594 if (!tcf_chain_dump(chain, q, parent, skb, cb, 2595 index_start, &index)) { 2596 tcf_chain_put(chain); 2597 err = -EMSGSIZE; 2598 break; 2599 } 2600 } 2601 2602 if (tcm->tcm_ifindex == TCM_IFINDEX_MAGIC_BLOCK) 2603 tcf_block_refcnt_put(block, true); 2604 cb->args[0] = index; 2605 2606 out: 2607 /* If we did no progress, the error (EMSGSIZE) is real */ 2608 if (skb->len == 0 && err) 2609 return err; 2610 return skb->len; 2611 } 2612 2613 static int tc_chain_fill_node(const struct tcf_proto_ops *tmplt_ops, 2614 void *tmplt_priv, u32 chain_index, 2615 struct net *net, struct sk_buff *skb, 2616 struct tcf_block *block, 2617 u32 portid, u32 seq, u16 flags, int event) 2618 { 2619 unsigned char *b = skb_tail_pointer(skb); 2620 const struct tcf_proto_ops *ops; 2621 struct nlmsghdr *nlh; 2622 struct tcmsg *tcm; 2623 void *priv; 2624 2625 ops = tmplt_ops; 2626 priv = tmplt_priv; 2627 2628 nlh = nlmsg_put(skb, portid, seq, event, sizeof(*tcm), flags); 2629 if (!nlh) 2630 goto out_nlmsg_trim; 2631 tcm = nlmsg_data(nlh); 2632 tcm->tcm_family = AF_UNSPEC; 2633 tcm->tcm__pad1 = 0; 2634 tcm->tcm__pad2 = 0; 2635 tcm->tcm_handle = 0; 2636 if (block->q) { 2637 tcm->tcm_ifindex = qdisc_dev(block->q)->ifindex; 2638 tcm->tcm_parent = block->q->handle; 2639 } else { 2640 tcm->tcm_ifindex = TCM_IFINDEX_MAGIC_BLOCK; 2641 tcm->tcm_block_index = block->index; 2642 } 2643 2644 if (nla_put_u32(skb, TCA_CHAIN, chain_index)) 2645 goto nla_put_failure; 2646 2647 if (ops) { 2648 if (nla_put_string(skb, TCA_KIND, ops->kind)) 2649 goto nla_put_failure; 2650 if (ops->tmplt_dump(skb, net, priv) < 0) 2651 goto nla_put_failure; 2652 } 2653 2654 nlh->nlmsg_len = skb_tail_pointer(skb) - b; 2655 return skb->len; 2656 2657 out_nlmsg_trim: 2658 nla_put_failure: 2659 nlmsg_trim(skb, b); 2660 return -EMSGSIZE; 2661 } 2662 2663 static int tc_chain_notify(struct tcf_chain *chain, struct sk_buff *oskb, 2664 u32 seq, u16 flags, int event, bool unicast) 2665 { 2666 u32 portid = oskb ? NETLINK_CB(oskb).portid : 0; 2667 struct tcf_block *block = chain->block; 2668 struct net *net = block->net; 2669 struct sk_buff *skb; 2670 int err = 0; 2671 2672 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL); 2673 if (!skb) 2674 return -ENOBUFS; 2675 2676 if (tc_chain_fill_node(chain->tmplt_ops, chain->tmplt_priv, 2677 chain->index, net, skb, block, portid, 2678 seq, flags, event) <= 0) { 2679 kfree_skb(skb); 2680 return -EINVAL; 2681 } 2682 2683 if (unicast) 2684 err = netlink_unicast(net->rtnl, skb, portid, MSG_DONTWAIT); 2685 else 2686 err = rtnetlink_send(skb, net, portid, RTNLGRP_TC, 2687 flags & NLM_F_ECHO); 2688 2689 if (err > 0) 2690 err = 0; 2691 return err; 2692 } 2693 2694 static int tc_chain_notify_delete(const struct tcf_proto_ops *tmplt_ops, 2695 void *tmplt_priv, u32 chain_index, 2696 struct tcf_block *block, struct sk_buff *oskb, 2697 u32 seq, u16 flags, bool unicast) 2698 { 2699 u32 portid = oskb ? NETLINK_CB(oskb).portid : 0; 2700 struct net *net = block->net; 2701 struct sk_buff *skb; 2702 2703 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL); 2704 if (!skb) 2705 return -ENOBUFS; 2706 2707 if (tc_chain_fill_node(tmplt_ops, tmplt_priv, chain_index, net, skb, 2708 block, portid, seq, flags, RTM_DELCHAIN) <= 0) { 2709 kfree_skb(skb); 2710 return -EINVAL; 2711 } 2712 2713 if (unicast) 2714 return netlink_unicast(net->rtnl, skb, portid, MSG_DONTWAIT); 2715 2716 return rtnetlink_send(skb, net, portid, RTNLGRP_TC, flags & NLM_F_ECHO); 2717 } 2718 2719 static int tc_chain_tmplt_add(struct tcf_chain *chain, struct net *net, 2720 struct nlattr **tca, 2721 struct netlink_ext_ack *extack) 2722 { 2723 const struct tcf_proto_ops *ops; 2724 void *tmplt_priv; 2725 2726 /* If kind is not set, user did not specify template. */ 2727 if (!tca[TCA_KIND]) 2728 return 0; 2729 2730 ops = tcf_proto_lookup_ops(nla_data(tca[TCA_KIND]), true, extack); 2731 if (IS_ERR(ops)) 2732 return PTR_ERR(ops); 2733 if (!ops->tmplt_create || !ops->tmplt_destroy || !ops->tmplt_dump) { 2734 NL_SET_ERR_MSG(extack, "Chain templates are not supported with specified classifier"); 2735 return -EOPNOTSUPP; 2736 } 2737 2738 tmplt_priv = ops->tmplt_create(net, chain, tca, extack); 2739 if (IS_ERR(tmplt_priv)) { 2740 module_put(ops->owner); 2741 return PTR_ERR(tmplt_priv); 2742 } 2743 chain->tmplt_ops = ops; 2744 chain->tmplt_priv = tmplt_priv; 2745 return 0; 2746 } 2747 2748 static void tc_chain_tmplt_del(const struct tcf_proto_ops *tmplt_ops, 2749 void *tmplt_priv) 2750 { 2751 /* If template ops are set, no work to do for us. */ 2752 if (!tmplt_ops) 2753 return; 2754 2755 tmplt_ops->tmplt_destroy(tmplt_priv); 2756 module_put(tmplt_ops->owner); 2757 } 2758 2759 /* Add/delete/get a chain */ 2760 2761 static int tc_ctl_chain(struct sk_buff *skb, struct nlmsghdr *n, 2762 struct netlink_ext_ack *extack) 2763 { 2764 struct net *net = sock_net(skb->sk); 2765 struct nlattr *tca[TCA_MAX + 1]; 2766 struct tcmsg *t; 2767 u32 parent; 2768 u32 chain_index; 2769 struct Qdisc *q = NULL; 2770 struct tcf_chain *chain = NULL; 2771 struct tcf_block *block; 2772 unsigned long cl; 2773 int err; 2774 2775 if (n->nlmsg_type != RTM_GETCHAIN && 2776 !netlink_ns_capable(skb, net->user_ns, CAP_NET_ADMIN)) 2777 return -EPERM; 2778 2779 replay: 2780 err = nlmsg_parse_deprecated(n, sizeof(*t), tca, TCA_MAX, 2781 rtm_tca_policy, extack); 2782 if (err < 0) 2783 return err; 2784 2785 t = nlmsg_data(n); 2786 parent = t->tcm_parent; 2787 cl = 0; 2788 2789 block = tcf_block_find(net, &q, &parent, &cl, 2790 t->tcm_ifindex, t->tcm_block_index, extack); 2791 if (IS_ERR(block)) 2792 return PTR_ERR(block); 2793 2794 chain_index = tca[TCA_CHAIN] ? nla_get_u32(tca[TCA_CHAIN]) : 0; 2795 if (chain_index > TC_ACT_EXT_VAL_MASK) { 2796 NL_SET_ERR_MSG(extack, "Specified chain index exceeds upper limit"); 2797 err = -EINVAL; 2798 goto errout_block; 2799 } 2800 2801 mutex_lock(&block->lock); 2802 chain = tcf_chain_lookup(block, chain_index); 2803 if (n->nlmsg_type == RTM_NEWCHAIN) { 2804 if (chain) { 2805 if (tcf_chain_held_by_acts_only(chain)) { 2806 /* The chain exists only because there is 2807 * some action referencing it. 2808 */ 2809 tcf_chain_hold(chain); 2810 } else { 2811 NL_SET_ERR_MSG(extack, "Filter chain already exists"); 2812 err = -EEXIST; 2813 goto errout_block_locked; 2814 } 2815 } else { 2816 if (!(n->nlmsg_flags & NLM_F_CREATE)) { 2817 NL_SET_ERR_MSG(extack, "Need both RTM_NEWCHAIN and NLM_F_CREATE to create a new chain"); 2818 err = -ENOENT; 2819 goto errout_block_locked; 2820 } 2821 chain = tcf_chain_create(block, chain_index); 2822 if (!chain) { 2823 NL_SET_ERR_MSG(extack, "Failed to create filter chain"); 2824 err = -ENOMEM; 2825 goto errout_block_locked; 2826 } 2827 } 2828 } else { 2829 if (!chain || tcf_chain_held_by_acts_only(chain)) { 2830 NL_SET_ERR_MSG(extack, "Cannot find specified filter chain"); 2831 err = -EINVAL; 2832 goto errout_block_locked; 2833 } 2834 tcf_chain_hold(chain); 2835 } 2836 2837 if (n->nlmsg_type == RTM_NEWCHAIN) { 2838 /* Modifying chain requires holding parent block lock. In case 2839 * the chain was successfully added, take a reference to the 2840 * chain. This ensures that an empty chain does not disappear at 2841 * the end of this function. 2842 */ 2843 tcf_chain_hold(chain); 2844 chain->explicitly_created = true; 2845 } 2846 mutex_unlock(&block->lock); 2847 2848 switch (n->nlmsg_type) { 2849 case RTM_NEWCHAIN: 2850 err = tc_chain_tmplt_add(chain, net, tca, extack); 2851 if (err) { 2852 tcf_chain_put_explicitly_created(chain); 2853 goto errout; 2854 } 2855 2856 tc_chain_notify(chain, NULL, 0, NLM_F_CREATE | NLM_F_EXCL, 2857 RTM_NEWCHAIN, false); 2858 break; 2859 case RTM_DELCHAIN: 2860 tfilter_notify_chain(net, skb, block, q, parent, n, 2861 chain, RTM_DELTFILTER, true); 2862 /* Flush the chain first as the user requested chain removal. */ 2863 tcf_chain_flush(chain, true); 2864 /* In case the chain was successfully deleted, put a reference 2865 * to the chain previously taken during addition. 2866 */ 2867 tcf_chain_put_explicitly_created(chain); 2868 break; 2869 case RTM_GETCHAIN: 2870 err = tc_chain_notify(chain, skb, n->nlmsg_seq, 2871 n->nlmsg_seq, n->nlmsg_type, true); 2872 if (err < 0) 2873 NL_SET_ERR_MSG(extack, "Failed to send chain notify message"); 2874 break; 2875 default: 2876 err = -EOPNOTSUPP; 2877 NL_SET_ERR_MSG(extack, "Unsupported message type"); 2878 goto errout; 2879 } 2880 2881 errout: 2882 tcf_chain_put(chain); 2883 errout_block: 2884 tcf_block_release(q, block, true); 2885 if (err == -EAGAIN) 2886 /* Replay the request. */ 2887 goto replay; 2888 return err; 2889 2890 errout_block_locked: 2891 mutex_unlock(&block->lock); 2892 goto errout_block; 2893 } 2894 2895 /* called with RTNL */ 2896 static int tc_dump_chain(struct sk_buff *skb, struct netlink_callback *cb) 2897 { 2898 struct net *net = sock_net(skb->sk); 2899 struct nlattr *tca[TCA_MAX + 1]; 2900 struct Qdisc *q = NULL; 2901 struct tcf_block *block; 2902 struct tcmsg *tcm = nlmsg_data(cb->nlh); 2903 struct tcf_chain *chain; 2904 long index_start; 2905 long index; 2906 u32 parent; 2907 int err; 2908 2909 if (nlmsg_len(cb->nlh) < sizeof(*tcm)) 2910 return skb->len; 2911 2912 err = nlmsg_parse_deprecated(cb->nlh, sizeof(*tcm), tca, TCA_MAX, 2913 rtm_tca_policy, cb->extack); 2914 if (err) 2915 return err; 2916 2917 if (tcm->tcm_ifindex == TCM_IFINDEX_MAGIC_BLOCK) { 2918 block = tcf_block_refcnt_get(net, tcm->tcm_block_index); 2919 if (!block) 2920 goto out; 2921 /* If we work with block index, q is NULL and parent value 2922 * will never be used in the following code. The check 2923 * in tcf_fill_node prevents it. However, compiler does not 2924 * see that far, so set parent to zero to silence the warning 2925 * about parent being uninitialized. 2926 */ 2927 parent = 0; 2928 } else { 2929 const struct Qdisc_class_ops *cops; 2930 struct net_device *dev; 2931 unsigned long cl = 0; 2932 2933 dev = __dev_get_by_index(net, tcm->tcm_ifindex); 2934 if (!dev) 2935 return skb->len; 2936 2937 parent = tcm->tcm_parent; 2938 if (!parent) { 2939 q = dev->qdisc; 2940 parent = q->handle; 2941 } else { 2942 q = qdisc_lookup(dev, TC_H_MAJ(tcm->tcm_parent)); 2943 } 2944 if (!q) 2945 goto out; 2946 cops = q->ops->cl_ops; 2947 if (!cops) 2948 goto out; 2949 if (!cops->tcf_block) 2950 goto out; 2951 if (TC_H_MIN(tcm->tcm_parent)) { 2952 cl = cops->find(q, tcm->tcm_parent); 2953 if (cl == 0) 2954 goto out; 2955 } 2956 block = cops->tcf_block(q, cl, NULL); 2957 if (!block) 2958 goto out; 2959 if (tcf_block_shared(block)) 2960 q = NULL; 2961 } 2962 2963 index_start = cb->args[0]; 2964 index = 0; 2965 2966 mutex_lock(&block->lock); 2967 list_for_each_entry(chain, &block->chain_list, list) { 2968 if ((tca[TCA_CHAIN] && 2969 nla_get_u32(tca[TCA_CHAIN]) != chain->index)) 2970 continue; 2971 if (index < index_start) { 2972 index++; 2973 continue; 2974 } 2975 if (tcf_chain_held_by_acts_only(chain)) 2976 continue; 2977 err = tc_chain_fill_node(chain->tmplt_ops, chain->tmplt_priv, 2978 chain->index, net, skb, block, 2979 NETLINK_CB(cb->skb).portid, 2980 cb->nlh->nlmsg_seq, NLM_F_MULTI, 2981 RTM_NEWCHAIN); 2982 if (err <= 0) 2983 break; 2984 index++; 2985 } 2986 mutex_unlock(&block->lock); 2987 2988 if (tcm->tcm_ifindex == TCM_IFINDEX_MAGIC_BLOCK) 2989 tcf_block_refcnt_put(block, true); 2990 cb->args[0] = index; 2991 2992 out: 2993 /* If we did no progress, the error (EMSGSIZE) is real */ 2994 if (skb->len == 0 && err) 2995 return err; 2996 return skb->len; 2997 } 2998 2999 void tcf_exts_destroy(struct tcf_exts *exts) 3000 { 3001 #ifdef CONFIG_NET_CLS_ACT 3002 if (exts->actions) { 3003 tcf_action_destroy(exts->actions, TCA_ACT_UNBIND); 3004 kfree(exts->actions); 3005 } 3006 exts->nr_actions = 0; 3007 #endif 3008 } 3009 EXPORT_SYMBOL(tcf_exts_destroy); 3010 3011 int tcf_exts_validate(struct net *net, struct tcf_proto *tp, struct nlattr **tb, 3012 struct nlattr *rate_tlv, struct tcf_exts *exts, bool ovr, 3013 bool rtnl_held, struct netlink_ext_ack *extack) 3014 { 3015 #ifdef CONFIG_NET_CLS_ACT 3016 { 3017 struct tc_action *act; 3018 size_t attr_size = 0; 3019 3020 if (exts->police && tb[exts->police]) { 3021 act = tcf_action_init_1(net, tp, tb[exts->police], 3022 rate_tlv, "police", ovr, 3023 TCA_ACT_BIND, rtnl_held, 3024 extack); 3025 if (IS_ERR(act)) 3026 return PTR_ERR(act); 3027 3028 act->type = exts->type = TCA_OLD_COMPAT; 3029 exts->actions[0] = act; 3030 exts->nr_actions = 1; 3031 } else if (exts->action && tb[exts->action]) { 3032 int err; 3033 3034 err = tcf_action_init(net, tp, tb[exts->action], 3035 rate_tlv, NULL, ovr, TCA_ACT_BIND, 3036 exts->actions, &attr_size, 3037 rtnl_held, extack); 3038 if (err < 0) 3039 return err; 3040 exts->nr_actions = err; 3041 } 3042 } 3043 #else 3044 if ((exts->action && tb[exts->action]) || 3045 (exts->police && tb[exts->police])) { 3046 NL_SET_ERR_MSG(extack, "Classifier actions are not supported per compile options (CONFIG_NET_CLS_ACT)"); 3047 return -EOPNOTSUPP; 3048 } 3049 #endif 3050 3051 return 0; 3052 } 3053 EXPORT_SYMBOL(tcf_exts_validate); 3054 3055 void tcf_exts_change(struct tcf_exts *dst, struct tcf_exts *src) 3056 { 3057 #ifdef CONFIG_NET_CLS_ACT 3058 struct tcf_exts old = *dst; 3059 3060 *dst = *src; 3061 tcf_exts_destroy(&old); 3062 #endif 3063 } 3064 EXPORT_SYMBOL(tcf_exts_change); 3065 3066 #ifdef CONFIG_NET_CLS_ACT 3067 static struct tc_action *tcf_exts_first_act(struct tcf_exts *exts) 3068 { 3069 if (exts->nr_actions == 0) 3070 return NULL; 3071 else 3072 return exts->actions[0]; 3073 } 3074 #endif 3075 3076 int tcf_exts_dump(struct sk_buff *skb, struct tcf_exts *exts) 3077 { 3078 #ifdef CONFIG_NET_CLS_ACT 3079 struct nlattr *nest; 3080 3081 if (exts->action && tcf_exts_has_actions(exts)) { 3082 /* 3083 * again for backward compatible mode - we want 3084 * to work with both old and new modes of entering 3085 * tc data even if iproute2 was newer - jhs 3086 */ 3087 if (exts->type != TCA_OLD_COMPAT) { 3088 nest = nla_nest_start_noflag(skb, exts->action); 3089 if (nest == NULL) 3090 goto nla_put_failure; 3091 3092 if (tcf_action_dump(skb, exts->actions, 0, 0) < 0) 3093 goto nla_put_failure; 3094 nla_nest_end(skb, nest); 3095 } else if (exts->police) { 3096 struct tc_action *act = tcf_exts_first_act(exts); 3097 nest = nla_nest_start_noflag(skb, exts->police); 3098 if (nest == NULL || !act) 3099 goto nla_put_failure; 3100 if (tcf_action_dump_old(skb, act, 0, 0) < 0) 3101 goto nla_put_failure; 3102 nla_nest_end(skb, nest); 3103 } 3104 } 3105 return 0; 3106 3107 nla_put_failure: 3108 nla_nest_cancel(skb, nest); 3109 return -1; 3110 #else 3111 return 0; 3112 #endif 3113 } 3114 EXPORT_SYMBOL(tcf_exts_dump); 3115 3116 3117 int tcf_exts_dump_stats(struct sk_buff *skb, struct tcf_exts *exts) 3118 { 3119 #ifdef CONFIG_NET_CLS_ACT 3120 struct tc_action *a = tcf_exts_first_act(exts); 3121 if (a != NULL && tcf_action_copy_stats(skb, a, 1) < 0) 3122 return -1; 3123 #endif 3124 return 0; 3125 } 3126 EXPORT_SYMBOL(tcf_exts_dump_stats); 3127 3128 static void tcf_block_offload_inc(struct tcf_block *block, u32 *flags) 3129 { 3130 if (*flags & TCA_CLS_FLAGS_IN_HW) 3131 return; 3132 *flags |= TCA_CLS_FLAGS_IN_HW; 3133 atomic_inc(&block->offloadcnt); 3134 } 3135 3136 static void tcf_block_offload_dec(struct tcf_block *block, u32 *flags) 3137 { 3138 if (!(*flags & TCA_CLS_FLAGS_IN_HW)) 3139 return; 3140 *flags &= ~TCA_CLS_FLAGS_IN_HW; 3141 atomic_dec(&block->offloadcnt); 3142 } 3143 3144 static void tc_cls_offload_cnt_update(struct tcf_block *block, 3145 struct tcf_proto *tp, u32 *cnt, 3146 u32 *flags, u32 diff, bool add) 3147 { 3148 lockdep_assert_held(&block->cb_lock); 3149 3150 spin_lock(&tp->lock); 3151 if (add) { 3152 if (!*cnt) 3153 tcf_block_offload_inc(block, flags); 3154 *cnt += diff; 3155 } else { 3156 *cnt -= diff; 3157 if (!*cnt) 3158 tcf_block_offload_dec(block, flags); 3159 } 3160 spin_unlock(&tp->lock); 3161 } 3162 3163 static void 3164 tc_cls_offload_cnt_reset(struct tcf_block *block, struct tcf_proto *tp, 3165 u32 *cnt, u32 *flags) 3166 { 3167 lockdep_assert_held(&block->cb_lock); 3168 3169 spin_lock(&tp->lock); 3170 tcf_block_offload_dec(block, flags); 3171 *cnt = 0; 3172 spin_unlock(&tp->lock); 3173 } 3174 3175 static int 3176 __tc_setup_cb_call(struct tcf_block *block, enum tc_setup_type type, 3177 void *type_data, bool err_stop) 3178 { 3179 struct flow_block_cb *block_cb; 3180 int ok_count = 0; 3181 int err; 3182 3183 list_for_each_entry(block_cb, &block->flow_block.cb_list, list) { 3184 err = block_cb->cb(type, type_data, block_cb->cb_priv); 3185 if (err) { 3186 if (err_stop) 3187 return err; 3188 } else { 3189 ok_count++; 3190 } 3191 } 3192 return ok_count; 3193 } 3194 3195 int tc_setup_cb_call(struct tcf_block *block, enum tc_setup_type type, 3196 void *type_data, bool err_stop, bool rtnl_held) 3197 { 3198 bool take_rtnl = READ_ONCE(block->lockeddevcnt) && !rtnl_held; 3199 int ok_count; 3200 3201 retry: 3202 if (take_rtnl) 3203 rtnl_lock(); 3204 down_read(&block->cb_lock); 3205 /* Need to obtain rtnl lock if block is bound to devs that require it. 3206 * In block bind code cb_lock is obtained while holding rtnl, so we must 3207 * obtain the locks in same order here. 3208 */ 3209 if (!rtnl_held && !take_rtnl && block->lockeddevcnt) { 3210 up_read(&block->cb_lock); 3211 take_rtnl = true; 3212 goto retry; 3213 } 3214 3215 ok_count = __tc_setup_cb_call(block, type, type_data, err_stop); 3216 3217 up_read(&block->cb_lock); 3218 if (take_rtnl) 3219 rtnl_unlock(); 3220 return ok_count; 3221 } 3222 EXPORT_SYMBOL(tc_setup_cb_call); 3223 3224 /* Non-destructive filter add. If filter that wasn't already in hardware is 3225 * successfully offloaded, increment block offloads counter. On failure, 3226 * previously offloaded filter is considered to be intact and offloads counter 3227 * is not decremented. 3228 */ 3229 3230 int tc_setup_cb_add(struct tcf_block *block, struct tcf_proto *tp, 3231 enum tc_setup_type type, void *type_data, bool err_stop, 3232 u32 *flags, unsigned int *in_hw_count, bool rtnl_held) 3233 { 3234 bool take_rtnl = READ_ONCE(block->lockeddevcnt) && !rtnl_held; 3235 int ok_count; 3236 3237 retry: 3238 if (take_rtnl) 3239 rtnl_lock(); 3240 down_read(&block->cb_lock); 3241 /* Need to obtain rtnl lock if block is bound to devs that require it. 3242 * In block bind code cb_lock is obtained while holding rtnl, so we must 3243 * obtain the locks in same order here. 3244 */ 3245 if (!rtnl_held && !take_rtnl && block->lockeddevcnt) { 3246 up_read(&block->cb_lock); 3247 take_rtnl = true; 3248 goto retry; 3249 } 3250 3251 /* Make sure all netdevs sharing this block are offload-capable. */ 3252 if (block->nooffloaddevcnt && err_stop) { 3253 ok_count = -EOPNOTSUPP; 3254 goto err_unlock; 3255 } 3256 3257 ok_count = __tc_setup_cb_call(block, type, type_data, err_stop); 3258 if (ok_count < 0) 3259 goto err_unlock; 3260 3261 if (tp->ops->hw_add) 3262 tp->ops->hw_add(tp, type_data); 3263 if (ok_count > 0) 3264 tc_cls_offload_cnt_update(block, tp, in_hw_count, flags, 3265 ok_count, true); 3266 err_unlock: 3267 up_read(&block->cb_lock); 3268 if (take_rtnl) 3269 rtnl_unlock(); 3270 return ok_count < 0 ? ok_count : 0; 3271 } 3272 EXPORT_SYMBOL(tc_setup_cb_add); 3273 3274 /* Destructive filter replace. If filter that wasn't already in hardware is 3275 * successfully offloaded, increment block offload counter. On failure, 3276 * previously offloaded filter is considered to be destroyed and offload counter 3277 * is decremented. 3278 */ 3279 3280 int tc_setup_cb_replace(struct tcf_block *block, struct tcf_proto *tp, 3281 enum tc_setup_type type, void *type_data, bool err_stop, 3282 u32 *old_flags, unsigned int *old_in_hw_count, 3283 u32 *new_flags, unsigned int *new_in_hw_count, 3284 bool rtnl_held) 3285 { 3286 bool take_rtnl = READ_ONCE(block->lockeddevcnt) && !rtnl_held; 3287 int ok_count; 3288 3289 retry: 3290 if (take_rtnl) 3291 rtnl_lock(); 3292 down_read(&block->cb_lock); 3293 /* Need to obtain rtnl lock if block is bound to devs that require it. 3294 * In block bind code cb_lock is obtained while holding rtnl, so we must 3295 * obtain the locks in same order here. 3296 */ 3297 if (!rtnl_held && !take_rtnl && block->lockeddevcnt) { 3298 up_read(&block->cb_lock); 3299 take_rtnl = true; 3300 goto retry; 3301 } 3302 3303 /* Make sure all netdevs sharing this block are offload-capable. */ 3304 if (block->nooffloaddevcnt && err_stop) { 3305 ok_count = -EOPNOTSUPP; 3306 goto err_unlock; 3307 } 3308 3309 tc_cls_offload_cnt_reset(block, tp, old_in_hw_count, old_flags); 3310 if (tp->ops->hw_del) 3311 tp->ops->hw_del(tp, type_data); 3312 3313 ok_count = __tc_setup_cb_call(block, type, type_data, err_stop); 3314 if (ok_count < 0) 3315 goto err_unlock; 3316 3317 if (tp->ops->hw_add) 3318 tp->ops->hw_add(tp, type_data); 3319 if (ok_count > 0) 3320 tc_cls_offload_cnt_update(block, tp, new_in_hw_count, 3321 new_flags, ok_count, true); 3322 err_unlock: 3323 up_read(&block->cb_lock); 3324 if (take_rtnl) 3325 rtnl_unlock(); 3326 return ok_count < 0 ? ok_count : 0; 3327 } 3328 EXPORT_SYMBOL(tc_setup_cb_replace); 3329 3330 /* Destroy filter and decrement block offload counter, if filter was previously 3331 * offloaded. 3332 */ 3333 3334 int tc_setup_cb_destroy(struct tcf_block *block, struct tcf_proto *tp, 3335 enum tc_setup_type type, void *type_data, bool err_stop, 3336 u32 *flags, unsigned int *in_hw_count, bool rtnl_held) 3337 { 3338 bool take_rtnl = READ_ONCE(block->lockeddevcnt) && !rtnl_held; 3339 int ok_count; 3340 3341 retry: 3342 if (take_rtnl) 3343 rtnl_lock(); 3344 down_read(&block->cb_lock); 3345 /* Need to obtain rtnl lock if block is bound to devs that require it. 3346 * In block bind code cb_lock is obtained while holding rtnl, so we must 3347 * obtain the locks in same order here. 3348 */ 3349 if (!rtnl_held && !take_rtnl && block->lockeddevcnt) { 3350 up_read(&block->cb_lock); 3351 take_rtnl = true; 3352 goto retry; 3353 } 3354 3355 ok_count = __tc_setup_cb_call(block, type, type_data, err_stop); 3356 3357 tc_cls_offload_cnt_reset(block, tp, in_hw_count, flags); 3358 if (tp->ops->hw_del) 3359 tp->ops->hw_del(tp, type_data); 3360 3361 up_read(&block->cb_lock); 3362 if (take_rtnl) 3363 rtnl_unlock(); 3364 return ok_count < 0 ? ok_count : 0; 3365 } 3366 EXPORT_SYMBOL(tc_setup_cb_destroy); 3367 3368 int tc_setup_cb_reoffload(struct tcf_block *block, struct tcf_proto *tp, 3369 bool add, flow_setup_cb_t *cb, 3370 enum tc_setup_type type, void *type_data, 3371 void *cb_priv, u32 *flags, unsigned int *in_hw_count) 3372 { 3373 int err = cb(type, type_data, cb_priv); 3374 3375 if (err) { 3376 if (add && tc_skip_sw(*flags)) 3377 return err; 3378 } else { 3379 tc_cls_offload_cnt_update(block, tp, in_hw_count, flags, 1, 3380 add); 3381 } 3382 3383 return 0; 3384 } 3385 EXPORT_SYMBOL(tc_setup_cb_reoffload); 3386 3387 void tc_cleanup_flow_action(struct flow_action *flow_action) 3388 { 3389 struct flow_action_entry *entry; 3390 int i; 3391 3392 flow_action_for_each(i, entry, flow_action) 3393 if (entry->destructor) 3394 entry->destructor(entry->destructor_priv); 3395 } 3396 EXPORT_SYMBOL(tc_cleanup_flow_action); 3397 3398 static void tcf_mirred_get_dev(struct flow_action_entry *entry, 3399 const struct tc_action *act) 3400 { 3401 #ifdef CONFIG_NET_CLS_ACT 3402 entry->dev = act->ops->get_dev(act, &entry->destructor); 3403 if (!entry->dev) 3404 return; 3405 entry->destructor_priv = entry->dev; 3406 #endif 3407 } 3408 3409 static void tcf_tunnel_encap_put_tunnel(void *priv) 3410 { 3411 struct ip_tunnel_info *tunnel = priv; 3412 3413 kfree(tunnel); 3414 } 3415 3416 static int tcf_tunnel_encap_get_tunnel(struct flow_action_entry *entry, 3417 const struct tc_action *act) 3418 { 3419 entry->tunnel = tcf_tunnel_info_copy(act); 3420 if (!entry->tunnel) 3421 return -ENOMEM; 3422 entry->destructor = tcf_tunnel_encap_put_tunnel; 3423 entry->destructor_priv = entry->tunnel; 3424 return 0; 3425 } 3426 3427 static void tcf_sample_get_group(struct flow_action_entry *entry, 3428 const struct tc_action *act) 3429 { 3430 #ifdef CONFIG_NET_CLS_ACT 3431 entry->sample.psample_group = 3432 act->ops->get_psample_group(act, &entry->destructor); 3433 entry->destructor_priv = entry->sample.psample_group; 3434 #endif 3435 } 3436 3437 int tc_setup_flow_action(struct flow_action *flow_action, 3438 const struct tcf_exts *exts, bool rtnl_held) 3439 { 3440 const struct tc_action *act; 3441 int i, j, k, err = 0; 3442 3443 if (!exts) 3444 return 0; 3445 3446 if (!rtnl_held) 3447 rtnl_lock(); 3448 3449 j = 0; 3450 tcf_exts_for_each_action(i, act, exts) { 3451 struct flow_action_entry *entry; 3452 3453 entry = &flow_action->entries[j]; 3454 if (is_tcf_gact_ok(act)) { 3455 entry->id = FLOW_ACTION_ACCEPT; 3456 } else if (is_tcf_gact_shot(act)) { 3457 entry->id = FLOW_ACTION_DROP; 3458 } else if (is_tcf_gact_trap(act)) { 3459 entry->id = FLOW_ACTION_TRAP; 3460 } else if (is_tcf_gact_goto_chain(act)) { 3461 entry->id = FLOW_ACTION_GOTO; 3462 entry->chain_index = tcf_gact_goto_chain_index(act); 3463 } else if (is_tcf_mirred_egress_redirect(act)) { 3464 entry->id = FLOW_ACTION_REDIRECT; 3465 tcf_mirred_get_dev(entry, act); 3466 } else if (is_tcf_mirred_egress_mirror(act)) { 3467 entry->id = FLOW_ACTION_MIRRED; 3468 tcf_mirred_get_dev(entry, act); 3469 } else if (is_tcf_mirred_ingress_redirect(act)) { 3470 entry->id = FLOW_ACTION_REDIRECT_INGRESS; 3471 tcf_mirred_get_dev(entry, act); 3472 } else if (is_tcf_mirred_ingress_mirror(act)) { 3473 entry->id = FLOW_ACTION_MIRRED_INGRESS; 3474 tcf_mirred_get_dev(entry, act); 3475 } else if (is_tcf_vlan(act)) { 3476 switch (tcf_vlan_action(act)) { 3477 case TCA_VLAN_ACT_PUSH: 3478 entry->id = FLOW_ACTION_VLAN_PUSH; 3479 entry->vlan.vid = tcf_vlan_push_vid(act); 3480 entry->vlan.proto = tcf_vlan_push_proto(act); 3481 entry->vlan.prio = tcf_vlan_push_prio(act); 3482 break; 3483 case TCA_VLAN_ACT_POP: 3484 entry->id = FLOW_ACTION_VLAN_POP; 3485 break; 3486 case TCA_VLAN_ACT_MODIFY: 3487 entry->id = FLOW_ACTION_VLAN_MANGLE; 3488 entry->vlan.vid = tcf_vlan_push_vid(act); 3489 entry->vlan.proto = tcf_vlan_push_proto(act); 3490 entry->vlan.prio = tcf_vlan_push_prio(act); 3491 break; 3492 default: 3493 err = -EOPNOTSUPP; 3494 goto err_out; 3495 } 3496 } else if (is_tcf_tunnel_set(act)) { 3497 entry->id = FLOW_ACTION_TUNNEL_ENCAP; 3498 err = tcf_tunnel_encap_get_tunnel(entry, act); 3499 if (err) 3500 goto err_out; 3501 } else if (is_tcf_tunnel_release(act)) { 3502 entry->id = FLOW_ACTION_TUNNEL_DECAP; 3503 } else if (is_tcf_pedit(act)) { 3504 for (k = 0; k < tcf_pedit_nkeys(act); k++) { 3505 switch (tcf_pedit_cmd(act, k)) { 3506 case TCA_PEDIT_KEY_EX_CMD_SET: 3507 entry->id = FLOW_ACTION_MANGLE; 3508 break; 3509 case TCA_PEDIT_KEY_EX_CMD_ADD: 3510 entry->id = FLOW_ACTION_ADD; 3511 break; 3512 default: 3513 err = -EOPNOTSUPP; 3514 goto err_out; 3515 } 3516 entry->mangle.htype = tcf_pedit_htype(act, k); 3517 entry->mangle.mask = tcf_pedit_mask(act, k); 3518 entry->mangle.val = tcf_pedit_val(act, k); 3519 entry->mangle.offset = tcf_pedit_offset(act, k); 3520 entry = &flow_action->entries[++j]; 3521 } 3522 } else if (is_tcf_csum(act)) { 3523 entry->id = FLOW_ACTION_CSUM; 3524 entry->csum_flags = tcf_csum_update_flags(act); 3525 } else if (is_tcf_skbedit_mark(act)) { 3526 entry->id = FLOW_ACTION_MARK; 3527 entry->mark = tcf_skbedit_mark(act); 3528 } else if (is_tcf_sample(act)) { 3529 entry->id = FLOW_ACTION_SAMPLE; 3530 entry->sample.trunc_size = tcf_sample_trunc_size(act); 3531 entry->sample.truncate = tcf_sample_truncate(act); 3532 entry->sample.rate = tcf_sample_rate(act); 3533 tcf_sample_get_group(entry, act); 3534 } else if (is_tcf_police(act)) { 3535 entry->id = FLOW_ACTION_POLICE; 3536 entry->police.burst = tcf_police_tcfp_burst(act); 3537 entry->police.rate_bytes_ps = 3538 tcf_police_rate_bytes_ps(act); 3539 } else if (is_tcf_ct(act)) { 3540 entry->id = FLOW_ACTION_CT; 3541 entry->ct.action = tcf_ct_action(act); 3542 entry->ct.zone = tcf_ct_zone(act); 3543 } else if (is_tcf_mpls(act)) { 3544 switch (tcf_mpls_action(act)) { 3545 case TCA_MPLS_ACT_PUSH: 3546 entry->id = FLOW_ACTION_MPLS_PUSH; 3547 entry->mpls_push.proto = tcf_mpls_proto(act); 3548 entry->mpls_push.label = tcf_mpls_label(act); 3549 entry->mpls_push.tc = tcf_mpls_tc(act); 3550 entry->mpls_push.bos = tcf_mpls_bos(act); 3551 entry->mpls_push.ttl = tcf_mpls_ttl(act); 3552 break; 3553 case TCA_MPLS_ACT_POP: 3554 entry->id = FLOW_ACTION_MPLS_POP; 3555 entry->mpls_pop.proto = tcf_mpls_proto(act); 3556 break; 3557 case TCA_MPLS_ACT_MODIFY: 3558 entry->id = FLOW_ACTION_MPLS_MANGLE; 3559 entry->mpls_mangle.label = tcf_mpls_label(act); 3560 entry->mpls_mangle.tc = tcf_mpls_tc(act); 3561 entry->mpls_mangle.bos = tcf_mpls_bos(act); 3562 entry->mpls_mangle.ttl = tcf_mpls_ttl(act); 3563 break; 3564 default: 3565 goto err_out; 3566 } 3567 } else if (is_tcf_skbedit_ptype(act)) { 3568 entry->id = FLOW_ACTION_PTYPE; 3569 entry->ptype = tcf_skbedit_ptype(act); 3570 } else { 3571 err = -EOPNOTSUPP; 3572 goto err_out; 3573 } 3574 3575 if (!is_tcf_pedit(act)) 3576 j++; 3577 } 3578 3579 err_out: 3580 if (!rtnl_held) 3581 rtnl_unlock(); 3582 3583 if (err) 3584 tc_cleanup_flow_action(flow_action); 3585 3586 return err; 3587 } 3588 EXPORT_SYMBOL(tc_setup_flow_action); 3589 3590 unsigned int tcf_exts_num_actions(struct tcf_exts *exts) 3591 { 3592 unsigned int num_acts = 0; 3593 struct tc_action *act; 3594 int i; 3595 3596 tcf_exts_for_each_action(i, act, exts) { 3597 if (is_tcf_pedit(act)) 3598 num_acts += tcf_pedit_nkeys(act); 3599 else 3600 num_acts++; 3601 } 3602 return num_acts; 3603 } 3604 EXPORT_SYMBOL(tcf_exts_num_actions); 3605 3606 static __net_init int tcf_net_init(struct net *net) 3607 { 3608 struct tcf_net *tn = net_generic(net, tcf_net_id); 3609 3610 spin_lock_init(&tn->idr_lock); 3611 idr_init(&tn->idr); 3612 return 0; 3613 } 3614 3615 static void __net_exit tcf_net_exit(struct net *net) 3616 { 3617 struct tcf_net *tn = net_generic(net, tcf_net_id); 3618 3619 idr_destroy(&tn->idr); 3620 } 3621 3622 static struct pernet_operations tcf_net_ops = { 3623 .init = tcf_net_init, 3624 .exit = tcf_net_exit, 3625 .id = &tcf_net_id, 3626 .size = sizeof(struct tcf_net), 3627 }; 3628 3629 static struct flow_indr_block_ing_entry block_ing_entry = { 3630 .cb = tc_indr_block_get_and_ing_cmd, 3631 .list = LIST_HEAD_INIT(block_ing_entry.list), 3632 }; 3633 3634 static int __init tc_filter_init(void) 3635 { 3636 int err; 3637 3638 tc_filter_wq = alloc_ordered_workqueue("tc_filter_workqueue", 0); 3639 if (!tc_filter_wq) 3640 return -ENOMEM; 3641 3642 err = register_pernet_subsys(&tcf_net_ops); 3643 if (err) 3644 goto err_register_pernet_subsys; 3645 3646 flow_indr_add_block_ing_cb(&block_ing_entry); 3647 3648 rtnl_register(PF_UNSPEC, RTM_NEWTFILTER, tc_new_tfilter, NULL, 3649 RTNL_FLAG_DOIT_UNLOCKED); 3650 rtnl_register(PF_UNSPEC, RTM_DELTFILTER, tc_del_tfilter, NULL, 3651 RTNL_FLAG_DOIT_UNLOCKED); 3652 rtnl_register(PF_UNSPEC, RTM_GETTFILTER, tc_get_tfilter, 3653 tc_dump_tfilter, RTNL_FLAG_DOIT_UNLOCKED); 3654 rtnl_register(PF_UNSPEC, RTM_NEWCHAIN, tc_ctl_chain, NULL, 0); 3655 rtnl_register(PF_UNSPEC, RTM_DELCHAIN, tc_ctl_chain, NULL, 0); 3656 rtnl_register(PF_UNSPEC, RTM_GETCHAIN, tc_ctl_chain, 3657 tc_dump_chain, 0); 3658 3659 return 0; 3660 3661 err_register_pernet_subsys: 3662 destroy_workqueue(tc_filter_wq); 3663 return err; 3664 } 3665 3666 subsys_initcall(tc_filter_init); 3667