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 <linux/rculist.h> 26 #include <net/net_namespace.h> 27 #include <net/sock.h> 28 #include <net/netlink.h> 29 #include <net/pkt_sched.h> 30 #include <net/pkt_cls.h> 31 #include <net/tc_act/tc_pedit.h> 32 #include <net/tc_act/tc_mirred.h> 33 #include <net/tc_act/tc_vlan.h> 34 #include <net/tc_act/tc_tunnel_key.h> 35 #include <net/tc_act/tc_csum.h> 36 #include <net/tc_act/tc_gact.h> 37 #include <net/tc_act/tc_police.h> 38 #include <net/tc_act/tc_sample.h> 39 #include <net/tc_act/tc_skbedit.h> 40 #include <net/tc_act/tc_ct.h> 41 #include <net/tc_act/tc_mpls.h> 42 #include <net/flow_offload.h> 43 44 extern const struct nla_policy rtm_tca_policy[TCA_MAX + 1]; 45 46 /* The list of all installed classifier types */ 47 static LIST_HEAD(tcf_proto_base); 48 49 /* Protects list of registered TC modules. It is pure SMP lock. */ 50 static DEFINE_RWLOCK(cls_mod_lock); 51 52 static u32 destroy_obj_hashfn(const struct tcf_proto *tp) 53 { 54 return jhash_3words(tp->chain->index, tp->prio, 55 (__force __u32)tp->protocol, 0); 56 } 57 58 static void tcf_proto_signal_destroying(struct tcf_chain *chain, 59 struct tcf_proto *tp) 60 { 61 struct tcf_block *block = chain->block; 62 63 mutex_lock(&block->proto_destroy_lock); 64 hash_add_rcu(block->proto_destroy_ht, &tp->destroy_ht_node, 65 destroy_obj_hashfn(tp)); 66 mutex_unlock(&block->proto_destroy_lock); 67 } 68 69 static bool tcf_proto_cmp(const struct tcf_proto *tp1, 70 const struct tcf_proto *tp2) 71 { 72 return tp1->chain->index == tp2->chain->index && 73 tp1->prio == tp2->prio && 74 tp1->protocol == tp2->protocol; 75 } 76 77 static bool tcf_proto_exists_destroying(struct tcf_chain *chain, 78 struct tcf_proto *tp) 79 { 80 u32 hash = destroy_obj_hashfn(tp); 81 struct tcf_proto *iter; 82 bool found = false; 83 84 rcu_read_lock(); 85 hash_for_each_possible_rcu(chain->block->proto_destroy_ht, iter, 86 destroy_ht_node, hash) { 87 if (tcf_proto_cmp(tp, iter)) { 88 found = true; 89 break; 90 } 91 } 92 rcu_read_unlock(); 93 94 return found; 95 } 96 97 static void 98 tcf_proto_signal_destroyed(struct tcf_chain *chain, struct tcf_proto *tp) 99 { 100 struct tcf_block *block = chain->block; 101 102 mutex_lock(&block->proto_destroy_lock); 103 if (hash_hashed(&tp->destroy_ht_node)) 104 hash_del_rcu(&tp->destroy_ht_node); 105 mutex_unlock(&block->proto_destroy_lock); 106 } 107 108 /* Find classifier type by string name */ 109 110 static const struct tcf_proto_ops *__tcf_proto_lookup_ops(const char *kind) 111 { 112 const struct tcf_proto_ops *t, *res = NULL; 113 114 if (kind) { 115 read_lock(&cls_mod_lock); 116 list_for_each_entry(t, &tcf_proto_base, head) { 117 if (strcmp(kind, t->kind) == 0) { 118 if (try_module_get(t->owner)) 119 res = t; 120 break; 121 } 122 } 123 read_unlock(&cls_mod_lock); 124 } 125 return res; 126 } 127 128 static const struct tcf_proto_ops * 129 tcf_proto_lookup_ops(const char *kind, bool rtnl_held, 130 struct netlink_ext_ack *extack) 131 { 132 const struct tcf_proto_ops *ops; 133 134 ops = __tcf_proto_lookup_ops(kind); 135 if (ops) 136 return ops; 137 #ifdef CONFIG_MODULES 138 if (rtnl_held) 139 rtnl_unlock(); 140 request_module("cls_%s", kind); 141 if (rtnl_held) 142 rtnl_lock(); 143 ops = __tcf_proto_lookup_ops(kind); 144 /* We dropped the RTNL semaphore in order to perform 145 * the module load. So, even if we succeeded in loading 146 * the module we have to replay the request. We indicate 147 * this using -EAGAIN. 148 */ 149 if (ops) { 150 module_put(ops->owner); 151 return ERR_PTR(-EAGAIN); 152 } 153 #endif 154 NL_SET_ERR_MSG(extack, "TC classifier not found"); 155 return ERR_PTR(-ENOENT); 156 } 157 158 /* Register(unregister) new classifier type */ 159 160 int register_tcf_proto_ops(struct tcf_proto_ops *ops) 161 { 162 struct tcf_proto_ops *t; 163 int rc = -EEXIST; 164 165 write_lock(&cls_mod_lock); 166 list_for_each_entry(t, &tcf_proto_base, head) 167 if (!strcmp(ops->kind, t->kind)) 168 goto out; 169 170 list_add_tail(&ops->head, &tcf_proto_base); 171 rc = 0; 172 out: 173 write_unlock(&cls_mod_lock); 174 return rc; 175 } 176 EXPORT_SYMBOL(register_tcf_proto_ops); 177 178 static struct workqueue_struct *tc_filter_wq; 179 180 int unregister_tcf_proto_ops(struct tcf_proto_ops *ops) 181 { 182 struct tcf_proto_ops *t; 183 int rc = -ENOENT; 184 185 /* Wait for outstanding call_rcu()s, if any, from a 186 * tcf_proto_ops's destroy() handler. 187 */ 188 rcu_barrier(); 189 flush_workqueue(tc_filter_wq); 190 191 write_lock(&cls_mod_lock); 192 list_for_each_entry(t, &tcf_proto_base, head) { 193 if (t == ops) { 194 list_del(&t->head); 195 rc = 0; 196 break; 197 } 198 } 199 write_unlock(&cls_mod_lock); 200 return rc; 201 } 202 EXPORT_SYMBOL(unregister_tcf_proto_ops); 203 204 bool tcf_queue_work(struct rcu_work *rwork, work_func_t func) 205 { 206 INIT_RCU_WORK(rwork, func); 207 return queue_rcu_work(tc_filter_wq, rwork); 208 } 209 EXPORT_SYMBOL(tcf_queue_work); 210 211 /* Select new prio value from the range, managed by kernel. */ 212 213 static inline u32 tcf_auto_prio(struct tcf_proto *tp) 214 { 215 u32 first = TC_H_MAKE(0xC0000000U, 0U); 216 217 if (tp) 218 first = tp->prio - 1; 219 220 return TC_H_MAJ(first); 221 } 222 223 static bool tcf_proto_check_kind(struct nlattr *kind, char *name) 224 { 225 if (kind) 226 return nla_strlcpy(name, kind, IFNAMSIZ) >= IFNAMSIZ; 227 memset(name, 0, IFNAMSIZ); 228 return false; 229 } 230 231 static bool tcf_proto_is_unlocked(const char *kind) 232 { 233 const struct tcf_proto_ops *ops; 234 bool ret; 235 236 if (strlen(kind) == 0) 237 return false; 238 239 ops = tcf_proto_lookup_ops(kind, false, NULL); 240 /* On error return false to take rtnl lock. Proto lookup/create 241 * functions will perform lookup again and properly handle errors. 242 */ 243 if (IS_ERR(ops)) 244 return false; 245 246 ret = !!(ops->flags & TCF_PROTO_OPS_DOIT_UNLOCKED); 247 module_put(ops->owner); 248 return ret; 249 } 250 251 static struct tcf_proto *tcf_proto_create(const char *kind, u32 protocol, 252 u32 prio, struct tcf_chain *chain, 253 bool rtnl_held, 254 struct netlink_ext_ack *extack) 255 { 256 struct tcf_proto *tp; 257 int err; 258 259 tp = kzalloc(sizeof(*tp), GFP_KERNEL); 260 if (!tp) 261 return ERR_PTR(-ENOBUFS); 262 263 tp->ops = tcf_proto_lookup_ops(kind, rtnl_held, extack); 264 if (IS_ERR(tp->ops)) { 265 err = PTR_ERR(tp->ops); 266 goto errout; 267 } 268 tp->classify = tp->ops->classify; 269 tp->protocol = protocol; 270 tp->prio = prio; 271 tp->chain = chain; 272 spin_lock_init(&tp->lock); 273 refcount_set(&tp->refcnt, 1); 274 275 err = tp->ops->init(tp); 276 if (err) { 277 module_put(tp->ops->owner); 278 goto errout; 279 } 280 return tp; 281 282 errout: 283 kfree(tp); 284 return ERR_PTR(err); 285 } 286 287 static void tcf_proto_get(struct tcf_proto *tp) 288 { 289 refcount_inc(&tp->refcnt); 290 } 291 292 static void tcf_chain_put(struct tcf_chain *chain); 293 294 static void tcf_proto_destroy(struct tcf_proto *tp, bool rtnl_held, 295 bool sig_destroy, struct netlink_ext_ack *extack) 296 { 297 tp->ops->destroy(tp, rtnl_held, extack); 298 if (sig_destroy) 299 tcf_proto_signal_destroyed(tp->chain, tp); 300 tcf_chain_put(tp->chain); 301 module_put(tp->ops->owner); 302 kfree_rcu(tp, rcu); 303 } 304 305 static void tcf_proto_put(struct tcf_proto *tp, bool rtnl_held, 306 struct netlink_ext_ack *extack) 307 { 308 if (refcount_dec_and_test(&tp->refcnt)) 309 tcf_proto_destroy(tp, rtnl_held, true, extack); 310 } 311 312 static bool tcf_proto_check_delete(struct tcf_proto *tp) 313 { 314 if (tp->ops->delete_empty) 315 return tp->ops->delete_empty(tp); 316 317 tp->deleting = true; 318 return tp->deleting; 319 } 320 321 static void tcf_proto_mark_delete(struct tcf_proto *tp) 322 { 323 spin_lock(&tp->lock); 324 tp->deleting = true; 325 spin_unlock(&tp->lock); 326 } 327 328 static bool tcf_proto_is_deleting(struct tcf_proto *tp) 329 { 330 bool deleting; 331 332 spin_lock(&tp->lock); 333 deleting = tp->deleting; 334 spin_unlock(&tp->lock); 335 336 return deleting; 337 } 338 339 #define ASSERT_BLOCK_LOCKED(block) \ 340 lockdep_assert_held(&(block)->lock) 341 342 struct tcf_filter_chain_list_item { 343 struct list_head list; 344 tcf_chain_head_change_t *chain_head_change; 345 void *chain_head_change_priv; 346 }; 347 348 static struct tcf_chain *tcf_chain_create(struct tcf_block *block, 349 u32 chain_index) 350 { 351 struct tcf_chain *chain; 352 353 ASSERT_BLOCK_LOCKED(block); 354 355 chain = kzalloc(sizeof(*chain), GFP_KERNEL); 356 if (!chain) 357 return NULL; 358 list_add_tail_rcu(&chain->list, &block->chain_list); 359 mutex_init(&chain->filter_chain_lock); 360 chain->block = block; 361 chain->index = chain_index; 362 chain->refcnt = 1; 363 if (!chain->index) 364 block->chain0.chain = chain; 365 return chain; 366 } 367 368 static void tcf_chain_head_change_item(struct tcf_filter_chain_list_item *item, 369 struct tcf_proto *tp_head) 370 { 371 if (item->chain_head_change) 372 item->chain_head_change(tp_head, item->chain_head_change_priv); 373 } 374 375 static void tcf_chain0_head_change(struct tcf_chain *chain, 376 struct tcf_proto *tp_head) 377 { 378 struct tcf_filter_chain_list_item *item; 379 struct tcf_block *block = chain->block; 380 381 if (chain->index) 382 return; 383 384 mutex_lock(&block->lock); 385 list_for_each_entry(item, &block->chain0.filter_chain_list, list) 386 tcf_chain_head_change_item(item, tp_head); 387 mutex_unlock(&block->lock); 388 } 389 390 /* Returns true if block can be safely freed. */ 391 392 static bool tcf_chain_detach(struct tcf_chain *chain) 393 { 394 struct tcf_block *block = chain->block; 395 396 ASSERT_BLOCK_LOCKED(block); 397 398 list_del_rcu(&chain->list); 399 if (!chain->index) 400 block->chain0.chain = NULL; 401 402 if (list_empty(&block->chain_list) && 403 refcount_read(&block->refcnt) == 0) 404 return true; 405 406 return false; 407 } 408 409 static void tcf_block_destroy(struct tcf_block *block) 410 { 411 mutex_destroy(&block->lock); 412 mutex_destroy(&block->proto_destroy_lock); 413 kfree_rcu(block, rcu); 414 } 415 416 static void tcf_chain_destroy(struct tcf_chain *chain, bool free_block) 417 { 418 struct tcf_block *block = chain->block; 419 420 mutex_destroy(&chain->filter_chain_lock); 421 kfree_rcu(chain, rcu); 422 if (free_block) 423 tcf_block_destroy(block); 424 } 425 426 static void tcf_chain_hold(struct tcf_chain *chain) 427 { 428 ASSERT_BLOCK_LOCKED(chain->block); 429 430 ++chain->refcnt; 431 } 432 433 static bool tcf_chain_held_by_acts_only(struct tcf_chain *chain) 434 { 435 ASSERT_BLOCK_LOCKED(chain->block); 436 437 /* In case all the references are action references, this 438 * chain should not be shown to the user. 439 */ 440 return chain->refcnt == chain->action_refcnt; 441 } 442 443 static struct tcf_chain *tcf_chain_lookup(struct tcf_block *block, 444 u32 chain_index) 445 { 446 struct tcf_chain *chain; 447 448 ASSERT_BLOCK_LOCKED(block); 449 450 list_for_each_entry(chain, &block->chain_list, list) { 451 if (chain->index == chain_index) 452 return chain; 453 } 454 return NULL; 455 } 456 457 #if IS_ENABLED(CONFIG_NET_TC_SKB_EXT) 458 static struct tcf_chain *tcf_chain_lookup_rcu(const struct tcf_block *block, 459 u32 chain_index) 460 { 461 struct tcf_chain *chain; 462 463 list_for_each_entry_rcu(chain, &block->chain_list, list) { 464 if (chain->index == chain_index) 465 return chain; 466 } 467 return NULL; 468 } 469 #endif 470 471 static int tc_chain_notify(struct tcf_chain *chain, struct sk_buff *oskb, 472 u32 seq, u16 flags, int event, bool unicast); 473 474 static struct tcf_chain *__tcf_chain_get(struct tcf_block *block, 475 u32 chain_index, bool create, 476 bool by_act) 477 { 478 struct tcf_chain *chain = NULL; 479 bool is_first_reference; 480 481 mutex_lock(&block->lock); 482 chain = tcf_chain_lookup(block, chain_index); 483 if (chain) { 484 tcf_chain_hold(chain); 485 } else { 486 if (!create) 487 goto errout; 488 chain = tcf_chain_create(block, chain_index); 489 if (!chain) 490 goto errout; 491 } 492 493 if (by_act) 494 ++chain->action_refcnt; 495 is_first_reference = chain->refcnt - chain->action_refcnt == 1; 496 mutex_unlock(&block->lock); 497 498 /* Send notification only in case we got the first 499 * non-action reference. Until then, the chain acts only as 500 * a placeholder for actions pointing to it and user ought 501 * not know about them. 502 */ 503 if (is_first_reference && !by_act) 504 tc_chain_notify(chain, NULL, 0, NLM_F_CREATE | NLM_F_EXCL, 505 RTM_NEWCHAIN, false); 506 507 return chain; 508 509 errout: 510 mutex_unlock(&block->lock); 511 return chain; 512 } 513 514 static struct tcf_chain *tcf_chain_get(struct tcf_block *block, u32 chain_index, 515 bool create) 516 { 517 return __tcf_chain_get(block, chain_index, create, false); 518 } 519 520 struct tcf_chain *tcf_chain_get_by_act(struct tcf_block *block, u32 chain_index) 521 { 522 return __tcf_chain_get(block, chain_index, true, true); 523 } 524 EXPORT_SYMBOL(tcf_chain_get_by_act); 525 526 static void tc_chain_tmplt_del(const struct tcf_proto_ops *tmplt_ops, 527 void *tmplt_priv); 528 static int tc_chain_notify_delete(const struct tcf_proto_ops *tmplt_ops, 529 void *tmplt_priv, u32 chain_index, 530 struct tcf_block *block, struct sk_buff *oskb, 531 u32 seq, u16 flags, bool unicast); 532 533 static void __tcf_chain_put(struct tcf_chain *chain, bool by_act, 534 bool explicitly_created) 535 { 536 struct tcf_block *block = chain->block; 537 const struct tcf_proto_ops *tmplt_ops; 538 bool free_block = false; 539 unsigned int refcnt; 540 void *tmplt_priv; 541 542 mutex_lock(&block->lock); 543 if (explicitly_created) { 544 if (!chain->explicitly_created) { 545 mutex_unlock(&block->lock); 546 return; 547 } 548 chain->explicitly_created = false; 549 } 550 551 if (by_act) 552 chain->action_refcnt--; 553 554 /* tc_chain_notify_delete can't be called while holding block lock. 555 * However, when block is unlocked chain can be changed concurrently, so 556 * save these to temporary variables. 557 */ 558 refcnt = --chain->refcnt; 559 tmplt_ops = chain->tmplt_ops; 560 tmplt_priv = chain->tmplt_priv; 561 562 /* The last dropped non-action reference will trigger notification. */ 563 if (refcnt - chain->action_refcnt == 0 && !by_act) { 564 tc_chain_notify_delete(tmplt_ops, tmplt_priv, chain->index, 565 block, NULL, 0, 0, false); 566 /* Last reference to chain, no need to lock. */ 567 chain->flushing = false; 568 } 569 570 if (refcnt == 0) 571 free_block = tcf_chain_detach(chain); 572 mutex_unlock(&block->lock); 573 574 if (refcnt == 0) { 575 tc_chain_tmplt_del(tmplt_ops, tmplt_priv); 576 tcf_chain_destroy(chain, free_block); 577 } 578 } 579 580 static void tcf_chain_put(struct tcf_chain *chain) 581 { 582 __tcf_chain_put(chain, false, false); 583 } 584 585 void tcf_chain_put_by_act(struct tcf_chain *chain) 586 { 587 __tcf_chain_put(chain, true, false); 588 } 589 EXPORT_SYMBOL(tcf_chain_put_by_act); 590 591 static void tcf_chain_put_explicitly_created(struct tcf_chain *chain) 592 { 593 __tcf_chain_put(chain, false, true); 594 } 595 596 static void tcf_chain_flush(struct tcf_chain *chain, bool rtnl_held) 597 { 598 struct tcf_proto *tp, *tp_next; 599 600 mutex_lock(&chain->filter_chain_lock); 601 tp = tcf_chain_dereference(chain->filter_chain, chain); 602 while (tp) { 603 tp_next = rcu_dereference_protected(tp->next, 1); 604 tcf_proto_signal_destroying(chain, tp); 605 tp = tp_next; 606 } 607 tp = tcf_chain_dereference(chain->filter_chain, chain); 608 RCU_INIT_POINTER(chain->filter_chain, NULL); 609 tcf_chain0_head_change(chain, NULL); 610 chain->flushing = true; 611 mutex_unlock(&chain->filter_chain_lock); 612 613 while (tp) { 614 tp_next = rcu_dereference_protected(tp->next, 1); 615 tcf_proto_put(tp, rtnl_held, NULL); 616 tp = tp_next; 617 } 618 } 619 620 static int tcf_block_setup(struct tcf_block *block, 621 struct flow_block_offload *bo); 622 623 static void tc_indr_block_cmd(struct net_device *dev, struct tcf_block *block, 624 flow_indr_block_bind_cb_t *cb, void *cb_priv, 625 enum flow_block_command command, bool ingress) 626 { 627 struct flow_block_offload bo = { 628 .command = command, 629 .binder_type = ingress ? 630 FLOW_BLOCK_BINDER_TYPE_CLSACT_INGRESS : 631 FLOW_BLOCK_BINDER_TYPE_CLSACT_EGRESS, 632 .net = dev_net(dev), 633 .block_shared = tcf_block_non_null_shared(block), 634 }; 635 INIT_LIST_HEAD(&bo.cb_list); 636 637 if (!block) 638 return; 639 640 bo.block = &block->flow_block; 641 642 down_write(&block->cb_lock); 643 cb(dev, cb_priv, TC_SETUP_BLOCK, &bo); 644 645 tcf_block_setup(block, &bo); 646 up_write(&block->cb_lock); 647 } 648 649 static struct tcf_block *tc_dev_block(struct net_device *dev, bool ingress) 650 { 651 const struct Qdisc_class_ops *cops; 652 const struct Qdisc_ops *ops; 653 struct Qdisc *qdisc; 654 655 if (!dev_ingress_queue(dev)) 656 return NULL; 657 658 qdisc = dev_ingress_queue(dev)->qdisc_sleeping; 659 if (!qdisc) 660 return NULL; 661 662 ops = qdisc->ops; 663 if (!ops) 664 return NULL; 665 666 if (!ingress && !strcmp("ingress", ops->id)) 667 return NULL; 668 669 cops = ops->cl_ops; 670 if (!cops) 671 return NULL; 672 673 if (!cops->tcf_block) 674 return NULL; 675 676 return cops->tcf_block(qdisc, 677 ingress ? TC_H_MIN_INGRESS : TC_H_MIN_EGRESS, 678 NULL); 679 } 680 681 static void tc_indr_block_get_and_cmd(struct net_device *dev, 682 flow_indr_block_bind_cb_t *cb, 683 void *cb_priv, 684 enum flow_block_command command) 685 { 686 struct tcf_block *block; 687 688 block = tc_dev_block(dev, true); 689 tc_indr_block_cmd(dev, block, cb, cb_priv, command, true); 690 691 block = tc_dev_block(dev, false); 692 tc_indr_block_cmd(dev, block, cb, cb_priv, command, false); 693 } 694 695 static void tc_indr_block_call(struct tcf_block *block, 696 struct net_device *dev, 697 struct tcf_block_ext_info *ei, 698 enum flow_block_command command, 699 struct netlink_ext_ack *extack) 700 { 701 struct flow_block_offload bo = { 702 .command = command, 703 .binder_type = ei->binder_type, 704 .net = dev_net(dev), 705 .block = &block->flow_block, 706 .block_shared = tcf_block_shared(block), 707 .extack = extack, 708 }; 709 INIT_LIST_HEAD(&bo.cb_list); 710 711 flow_indr_block_call(dev, &bo, command, TC_SETUP_BLOCK); 712 tcf_block_setup(block, &bo); 713 } 714 715 static bool tcf_block_offload_in_use(struct tcf_block *block) 716 { 717 return atomic_read(&block->offloadcnt); 718 } 719 720 static int tcf_block_offload_cmd(struct tcf_block *block, 721 struct net_device *dev, 722 struct tcf_block_ext_info *ei, 723 enum flow_block_command command, 724 struct netlink_ext_ack *extack) 725 { 726 struct flow_block_offload bo = {}; 727 int err; 728 729 bo.net = dev_net(dev); 730 bo.command = command; 731 bo.binder_type = ei->binder_type; 732 bo.block = &block->flow_block; 733 bo.block_shared = tcf_block_shared(block); 734 bo.extack = extack; 735 INIT_LIST_HEAD(&bo.cb_list); 736 737 err = dev->netdev_ops->ndo_setup_tc(dev, TC_SETUP_BLOCK, &bo); 738 if (err < 0) 739 return err; 740 741 return tcf_block_setup(block, &bo); 742 } 743 744 static int tcf_block_offload_bind(struct tcf_block *block, struct Qdisc *q, 745 struct tcf_block_ext_info *ei, 746 struct netlink_ext_ack *extack) 747 { 748 struct net_device *dev = q->dev_queue->dev; 749 int err; 750 751 down_write(&block->cb_lock); 752 if (!dev->netdev_ops->ndo_setup_tc) 753 goto no_offload_dev_inc; 754 755 /* If tc offload feature is disabled and the block we try to bind 756 * to already has some offloaded filters, forbid to bind. 757 */ 758 if (!tc_can_offload(dev) && tcf_block_offload_in_use(block)) { 759 NL_SET_ERR_MSG(extack, "Bind to offloaded block failed as dev has offload disabled"); 760 err = -EOPNOTSUPP; 761 goto err_unlock; 762 } 763 764 err = tcf_block_offload_cmd(block, dev, ei, FLOW_BLOCK_BIND, extack); 765 if (err == -EOPNOTSUPP) 766 goto no_offload_dev_inc; 767 if (err) 768 goto err_unlock; 769 770 tc_indr_block_call(block, dev, ei, FLOW_BLOCK_BIND, extack); 771 up_write(&block->cb_lock); 772 return 0; 773 774 no_offload_dev_inc: 775 if (tcf_block_offload_in_use(block)) { 776 err = -EOPNOTSUPP; 777 goto err_unlock; 778 } 779 err = 0; 780 block->nooffloaddevcnt++; 781 tc_indr_block_call(block, dev, ei, FLOW_BLOCK_BIND, extack); 782 err_unlock: 783 up_write(&block->cb_lock); 784 return err; 785 } 786 787 static void tcf_block_offload_unbind(struct tcf_block *block, struct Qdisc *q, 788 struct tcf_block_ext_info *ei) 789 { 790 struct net_device *dev = q->dev_queue->dev; 791 int err; 792 793 down_write(&block->cb_lock); 794 tc_indr_block_call(block, dev, ei, FLOW_BLOCK_UNBIND, NULL); 795 796 if (!dev->netdev_ops->ndo_setup_tc) 797 goto no_offload_dev_dec; 798 err = tcf_block_offload_cmd(block, dev, ei, FLOW_BLOCK_UNBIND, NULL); 799 if (err == -EOPNOTSUPP) 800 goto no_offload_dev_dec; 801 up_write(&block->cb_lock); 802 return; 803 804 no_offload_dev_dec: 805 WARN_ON(block->nooffloaddevcnt-- == 0); 806 up_write(&block->cb_lock); 807 } 808 809 static int 810 tcf_chain0_head_change_cb_add(struct tcf_block *block, 811 struct tcf_block_ext_info *ei, 812 struct netlink_ext_ack *extack) 813 { 814 struct tcf_filter_chain_list_item *item; 815 struct tcf_chain *chain0; 816 817 item = kmalloc(sizeof(*item), GFP_KERNEL); 818 if (!item) { 819 NL_SET_ERR_MSG(extack, "Memory allocation for head change callback item failed"); 820 return -ENOMEM; 821 } 822 item->chain_head_change = ei->chain_head_change; 823 item->chain_head_change_priv = ei->chain_head_change_priv; 824 825 mutex_lock(&block->lock); 826 chain0 = block->chain0.chain; 827 if (chain0) 828 tcf_chain_hold(chain0); 829 else 830 list_add(&item->list, &block->chain0.filter_chain_list); 831 mutex_unlock(&block->lock); 832 833 if (chain0) { 834 struct tcf_proto *tp_head; 835 836 mutex_lock(&chain0->filter_chain_lock); 837 838 tp_head = tcf_chain_dereference(chain0->filter_chain, chain0); 839 if (tp_head) 840 tcf_chain_head_change_item(item, tp_head); 841 842 mutex_lock(&block->lock); 843 list_add(&item->list, &block->chain0.filter_chain_list); 844 mutex_unlock(&block->lock); 845 846 mutex_unlock(&chain0->filter_chain_lock); 847 tcf_chain_put(chain0); 848 } 849 850 return 0; 851 } 852 853 static void 854 tcf_chain0_head_change_cb_del(struct tcf_block *block, 855 struct tcf_block_ext_info *ei) 856 { 857 struct tcf_filter_chain_list_item *item; 858 859 mutex_lock(&block->lock); 860 list_for_each_entry(item, &block->chain0.filter_chain_list, list) { 861 if ((!ei->chain_head_change && !ei->chain_head_change_priv) || 862 (item->chain_head_change == ei->chain_head_change && 863 item->chain_head_change_priv == ei->chain_head_change_priv)) { 864 if (block->chain0.chain) 865 tcf_chain_head_change_item(item, NULL); 866 list_del(&item->list); 867 mutex_unlock(&block->lock); 868 869 kfree(item); 870 return; 871 } 872 } 873 mutex_unlock(&block->lock); 874 WARN_ON(1); 875 } 876 877 struct tcf_net { 878 spinlock_t idr_lock; /* Protects idr */ 879 struct idr idr; 880 }; 881 882 static unsigned int tcf_net_id; 883 884 static int tcf_block_insert(struct tcf_block *block, struct net *net, 885 struct netlink_ext_ack *extack) 886 { 887 struct tcf_net *tn = net_generic(net, tcf_net_id); 888 int err; 889 890 idr_preload(GFP_KERNEL); 891 spin_lock(&tn->idr_lock); 892 err = idr_alloc_u32(&tn->idr, block, &block->index, block->index, 893 GFP_NOWAIT); 894 spin_unlock(&tn->idr_lock); 895 idr_preload_end(); 896 897 return err; 898 } 899 900 static void tcf_block_remove(struct tcf_block *block, struct net *net) 901 { 902 struct tcf_net *tn = net_generic(net, tcf_net_id); 903 904 spin_lock(&tn->idr_lock); 905 idr_remove(&tn->idr, block->index); 906 spin_unlock(&tn->idr_lock); 907 } 908 909 static struct tcf_block *tcf_block_create(struct net *net, struct Qdisc *q, 910 u32 block_index, 911 struct netlink_ext_ack *extack) 912 { 913 struct tcf_block *block; 914 915 block = kzalloc(sizeof(*block), GFP_KERNEL); 916 if (!block) { 917 NL_SET_ERR_MSG(extack, "Memory allocation for block failed"); 918 return ERR_PTR(-ENOMEM); 919 } 920 mutex_init(&block->lock); 921 mutex_init(&block->proto_destroy_lock); 922 init_rwsem(&block->cb_lock); 923 flow_block_init(&block->flow_block); 924 INIT_LIST_HEAD(&block->chain_list); 925 INIT_LIST_HEAD(&block->owner_list); 926 INIT_LIST_HEAD(&block->chain0.filter_chain_list); 927 928 refcount_set(&block->refcnt, 1); 929 block->net = net; 930 block->index = block_index; 931 932 /* Don't store q pointer for blocks which are shared */ 933 if (!tcf_block_shared(block)) 934 block->q = q; 935 return block; 936 } 937 938 static struct tcf_block *tcf_block_lookup(struct net *net, u32 block_index) 939 { 940 struct tcf_net *tn = net_generic(net, tcf_net_id); 941 942 return idr_find(&tn->idr, block_index); 943 } 944 945 static struct tcf_block *tcf_block_refcnt_get(struct net *net, u32 block_index) 946 { 947 struct tcf_block *block; 948 949 rcu_read_lock(); 950 block = tcf_block_lookup(net, block_index); 951 if (block && !refcount_inc_not_zero(&block->refcnt)) 952 block = NULL; 953 rcu_read_unlock(); 954 955 return block; 956 } 957 958 static struct tcf_chain * 959 __tcf_get_next_chain(struct tcf_block *block, struct tcf_chain *chain) 960 { 961 mutex_lock(&block->lock); 962 if (chain) 963 chain = list_is_last(&chain->list, &block->chain_list) ? 964 NULL : list_next_entry(chain, list); 965 else 966 chain = list_first_entry_or_null(&block->chain_list, 967 struct tcf_chain, list); 968 969 /* skip all action-only chains */ 970 while (chain && tcf_chain_held_by_acts_only(chain)) 971 chain = list_is_last(&chain->list, &block->chain_list) ? 972 NULL : list_next_entry(chain, list); 973 974 if (chain) 975 tcf_chain_hold(chain); 976 mutex_unlock(&block->lock); 977 978 return chain; 979 } 980 981 /* Function to be used by all clients that want to iterate over all chains on 982 * block. It properly obtains block->lock and takes reference to chain before 983 * returning it. Users of this function must be tolerant to concurrent chain 984 * insertion/deletion or ensure that no concurrent chain modification is 985 * possible. Note that all netlink dump callbacks cannot guarantee to provide 986 * consistent dump because rtnl lock is released each time skb is filled with 987 * data and sent to user-space. 988 */ 989 990 struct tcf_chain * 991 tcf_get_next_chain(struct tcf_block *block, struct tcf_chain *chain) 992 { 993 struct tcf_chain *chain_next = __tcf_get_next_chain(block, chain); 994 995 if (chain) 996 tcf_chain_put(chain); 997 998 return chain_next; 999 } 1000 EXPORT_SYMBOL(tcf_get_next_chain); 1001 1002 static struct tcf_proto * 1003 __tcf_get_next_proto(struct tcf_chain *chain, struct tcf_proto *tp) 1004 { 1005 u32 prio = 0; 1006 1007 ASSERT_RTNL(); 1008 mutex_lock(&chain->filter_chain_lock); 1009 1010 if (!tp) { 1011 tp = tcf_chain_dereference(chain->filter_chain, chain); 1012 } else if (tcf_proto_is_deleting(tp)) { 1013 /* 'deleting' flag is set and chain->filter_chain_lock was 1014 * unlocked, which means next pointer could be invalid. Restart 1015 * search. 1016 */ 1017 prio = tp->prio + 1; 1018 tp = tcf_chain_dereference(chain->filter_chain, chain); 1019 1020 for (; tp; tp = tcf_chain_dereference(tp->next, chain)) 1021 if (!tp->deleting && tp->prio >= prio) 1022 break; 1023 } else { 1024 tp = tcf_chain_dereference(tp->next, chain); 1025 } 1026 1027 if (tp) 1028 tcf_proto_get(tp); 1029 1030 mutex_unlock(&chain->filter_chain_lock); 1031 1032 return tp; 1033 } 1034 1035 /* Function to be used by all clients that want to iterate over all tp's on 1036 * chain. Users of this function must be tolerant to concurrent tp 1037 * insertion/deletion or ensure that no concurrent chain modification is 1038 * possible. Note that all netlink dump callbacks cannot guarantee to provide 1039 * consistent dump because rtnl lock is released each time skb is filled with 1040 * data and sent to user-space. 1041 */ 1042 1043 struct tcf_proto * 1044 tcf_get_next_proto(struct tcf_chain *chain, struct tcf_proto *tp, 1045 bool rtnl_held) 1046 { 1047 struct tcf_proto *tp_next = __tcf_get_next_proto(chain, tp); 1048 1049 if (tp) 1050 tcf_proto_put(tp, rtnl_held, NULL); 1051 1052 return tp_next; 1053 } 1054 EXPORT_SYMBOL(tcf_get_next_proto); 1055 1056 static void tcf_block_flush_all_chains(struct tcf_block *block, bool rtnl_held) 1057 { 1058 struct tcf_chain *chain; 1059 1060 /* Last reference to block. At this point chains cannot be added or 1061 * removed concurrently. 1062 */ 1063 for (chain = tcf_get_next_chain(block, NULL); 1064 chain; 1065 chain = tcf_get_next_chain(block, chain)) { 1066 tcf_chain_put_explicitly_created(chain); 1067 tcf_chain_flush(chain, rtnl_held); 1068 } 1069 } 1070 1071 /* Lookup Qdisc and increments its reference counter. 1072 * Set parent, if necessary. 1073 */ 1074 1075 static int __tcf_qdisc_find(struct net *net, struct Qdisc **q, 1076 u32 *parent, int ifindex, bool rtnl_held, 1077 struct netlink_ext_ack *extack) 1078 { 1079 const struct Qdisc_class_ops *cops; 1080 struct net_device *dev; 1081 int err = 0; 1082 1083 if (ifindex == TCM_IFINDEX_MAGIC_BLOCK) 1084 return 0; 1085 1086 rcu_read_lock(); 1087 1088 /* Find link */ 1089 dev = dev_get_by_index_rcu(net, ifindex); 1090 if (!dev) { 1091 rcu_read_unlock(); 1092 return -ENODEV; 1093 } 1094 1095 /* Find qdisc */ 1096 if (!*parent) { 1097 *q = dev->qdisc; 1098 *parent = (*q)->handle; 1099 } else { 1100 *q = qdisc_lookup_rcu(dev, TC_H_MAJ(*parent)); 1101 if (!*q) { 1102 NL_SET_ERR_MSG(extack, "Parent Qdisc doesn't exists"); 1103 err = -EINVAL; 1104 goto errout_rcu; 1105 } 1106 } 1107 1108 *q = qdisc_refcount_inc_nz(*q); 1109 if (!*q) { 1110 NL_SET_ERR_MSG(extack, "Parent Qdisc doesn't exists"); 1111 err = -EINVAL; 1112 goto errout_rcu; 1113 } 1114 1115 /* Is it classful? */ 1116 cops = (*q)->ops->cl_ops; 1117 if (!cops) { 1118 NL_SET_ERR_MSG(extack, "Qdisc not classful"); 1119 err = -EINVAL; 1120 goto errout_qdisc; 1121 } 1122 1123 if (!cops->tcf_block) { 1124 NL_SET_ERR_MSG(extack, "Class doesn't support blocks"); 1125 err = -EOPNOTSUPP; 1126 goto errout_qdisc; 1127 } 1128 1129 errout_rcu: 1130 /* At this point we know that qdisc is not noop_qdisc, 1131 * which means that qdisc holds a reference to net_device 1132 * and we hold a reference to qdisc, so it is safe to release 1133 * rcu read lock. 1134 */ 1135 rcu_read_unlock(); 1136 return err; 1137 1138 errout_qdisc: 1139 rcu_read_unlock(); 1140 1141 if (rtnl_held) 1142 qdisc_put(*q); 1143 else 1144 qdisc_put_unlocked(*q); 1145 *q = NULL; 1146 1147 return err; 1148 } 1149 1150 static int __tcf_qdisc_cl_find(struct Qdisc *q, u32 parent, unsigned long *cl, 1151 int ifindex, struct netlink_ext_ack *extack) 1152 { 1153 if (ifindex == TCM_IFINDEX_MAGIC_BLOCK) 1154 return 0; 1155 1156 /* Do we search for filter, attached to class? */ 1157 if (TC_H_MIN(parent)) { 1158 const struct Qdisc_class_ops *cops = q->ops->cl_ops; 1159 1160 *cl = cops->find(q, parent); 1161 if (*cl == 0) { 1162 NL_SET_ERR_MSG(extack, "Specified class doesn't exist"); 1163 return -ENOENT; 1164 } 1165 } 1166 1167 return 0; 1168 } 1169 1170 static struct tcf_block *__tcf_block_find(struct net *net, struct Qdisc *q, 1171 unsigned long cl, int ifindex, 1172 u32 block_index, 1173 struct netlink_ext_ack *extack) 1174 { 1175 struct tcf_block *block; 1176 1177 if (ifindex == TCM_IFINDEX_MAGIC_BLOCK) { 1178 block = tcf_block_refcnt_get(net, block_index); 1179 if (!block) { 1180 NL_SET_ERR_MSG(extack, "Block of given index was not found"); 1181 return ERR_PTR(-EINVAL); 1182 } 1183 } else { 1184 const struct Qdisc_class_ops *cops = q->ops->cl_ops; 1185 1186 block = cops->tcf_block(q, cl, extack); 1187 if (!block) 1188 return ERR_PTR(-EINVAL); 1189 1190 if (tcf_block_shared(block)) { 1191 NL_SET_ERR_MSG(extack, "This filter block is shared. Please use the block index to manipulate the filters"); 1192 return ERR_PTR(-EOPNOTSUPP); 1193 } 1194 1195 /* Always take reference to block in order to support execution 1196 * of rules update path of cls API without rtnl lock. Caller 1197 * must release block when it is finished using it. 'if' block 1198 * of this conditional obtain reference to block by calling 1199 * tcf_block_refcnt_get(). 1200 */ 1201 refcount_inc(&block->refcnt); 1202 } 1203 1204 return block; 1205 } 1206 1207 static void __tcf_block_put(struct tcf_block *block, struct Qdisc *q, 1208 struct tcf_block_ext_info *ei, bool rtnl_held) 1209 { 1210 if (refcount_dec_and_mutex_lock(&block->refcnt, &block->lock)) { 1211 /* Flushing/putting all chains will cause the block to be 1212 * deallocated when last chain is freed. However, if chain_list 1213 * is empty, block has to be manually deallocated. After block 1214 * reference counter reached 0, it is no longer possible to 1215 * increment it or add new chains to block. 1216 */ 1217 bool free_block = list_empty(&block->chain_list); 1218 1219 mutex_unlock(&block->lock); 1220 if (tcf_block_shared(block)) 1221 tcf_block_remove(block, block->net); 1222 1223 if (q) 1224 tcf_block_offload_unbind(block, q, ei); 1225 1226 if (free_block) 1227 tcf_block_destroy(block); 1228 else 1229 tcf_block_flush_all_chains(block, rtnl_held); 1230 } else if (q) { 1231 tcf_block_offload_unbind(block, q, ei); 1232 } 1233 } 1234 1235 static void tcf_block_refcnt_put(struct tcf_block *block, bool rtnl_held) 1236 { 1237 __tcf_block_put(block, NULL, NULL, rtnl_held); 1238 } 1239 1240 /* Find tcf block. 1241 * Set q, parent, cl when appropriate. 1242 */ 1243 1244 static struct tcf_block *tcf_block_find(struct net *net, struct Qdisc **q, 1245 u32 *parent, unsigned long *cl, 1246 int ifindex, u32 block_index, 1247 struct netlink_ext_ack *extack) 1248 { 1249 struct tcf_block *block; 1250 int err = 0; 1251 1252 ASSERT_RTNL(); 1253 1254 err = __tcf_qdisc_find(net, q, parent, ifindex, true, extack); 1255 if (err) 1256 goto errout; 1257 1258 err = __tcf_qdisc_cl_find(*q, *parent, cl, ifindex, extack); 1259 if (err) 1260 goto errout_qdisc; 1261 1262 block = __tcf_block_find(net, *q, *cl, ifindex, block_index, extack); 1263 if (IS_ERR(block)) { 1264 err = PTR_ERR(block); 1265 goto errout_qdisc; 1266 } 1267 1268 return block; 1269 1270 errout_qdisc: 1271 if (*q) 1272 qdisc_put(*q); 1273 errout: 1274 *q = NULL; 1275 return ERR_PTR(err); 1276 } 1277 1278 static void tcf_block_release(struct Qdisc *q, struct tcf_block *block, 1279 bool rtnl_held) 1280 { 1281 if (!IS_ERR_OR_NULL(block)) 1282 tcf_block_refcnt_put(block, rtnl_held); 1283 1284 if (q) { 1285 if (rtnl_held) 1286 qdisc_put(q); 1287 else 1288 qdisc_put_unlocked(q); 1289 } 1290 } 1291 1292 struct tcf_block_owner_item { 1293 struct list_head list; 1294 struct Qdisc *q; 1295 enum flow_block_binder_type binder_type; 1296 }; 1297 1298 static void 1299 tcf_block_owner_netif_keep_dst(struct tcf_block *block, 1300 struct Qdisc *q, 1301 enum flow_block_binder_type binder_type) 1302 { 1303 if (block->keep_dst && 1304 binder_type != FLOW_BLOCK_BINDER_TYPE_CLSACT_INGRESS && 1305 binder_type != FLOW_BLOCK_BINDER_TYPE_CLSACT_EGRESS) 1306 netif_keep_dst(qdisc_dev(q)); 1307 } 1308 1309 void tcf_block_netif_keep_dst(struct tcf_block *block) 1310 { 1311 struct tcf_block_owner_item *item; 1312 1313 block->keep_dst = true; 1314 list_for_each_entry(item, &block->owner_list, list) 1315 tcf_block_owner_netif_keep_dst(block, item->q, 1316 item->binder_type); 1317 } 1318 EXPORT_SYMBOL(tcf_block_netif_keep_dst); 1319 1320 static int tcf_block_owner_add(struct tcf_block *block, 1321 struct Qdisc *q, 1322 enum flow_block_binder_type binder_type) 1323 { 1324 struct tcf_block_owner_item *item; 1325 1326 item = kmalloc(sizeof(*item), GFP_KERNEL); 1327 if (!item) 1328 return -ENOMEM; 1329 item->q = q; 1330 item->binder_type = binder_type; 1331 list_add(&item->list, &block->owner_list); 1332 return 0; 1333 } 1334 1335 static void tcf_block_owner_del(struct tcf_block *block, 1336 struct Qdisc *q, 1337 enum flow_block_binder_type binder_type) 1338 { 1339 struct tcf_block_owner_item *item; 1340 1341 list_for_each_entry(item, &block->owner_list, list) { 1342 if (item->q == q && item->binder_type == binder_type) { 1343 list_del(&item->list); 1344 kfree(item); 1345 return; 1346 } 1347 } 1348 WARN_ON(1); 1349 } 1350 1351 int tcf_block_get_ext(struct tcf_block **p_block, struct Qdisc *q, 1352 struct tcf_block_ext_info *ei, 1353 struct netlink_ext_ack *extack) 1354 { 1355 struct net *net = qdisc_net(q); 1356 struct tcf_block *block = NULL; 1357 int err; 1358 1359 if (ei->block_index) 1360 /* block_index not 0 means the shared block is requested */ 1361 block = tcf_block_refcnt_get(net, ei->block_index); 1362 1363 if (!block) { 1364 block = tcf_block_create(net, q, ei->block_index, extack); 1365 if (IS_ERR(block)) 1366 return PTR_ERR(block); 1367 if (tcf_block_shared(block)) { 1368 err = tcf_block_insert(block, net, extack); 1369 if (err) 1370 goto err_block_insert; 1371 } 1372 } 1373 1374 err = tcf_block_owner_add(block, q, ei->binder_type); 1375 if (err) 1376 goto err_block_owner_add; 1377 1378 tcf_block_owner_netif_keep_dst(block, q, ei->binder_type); 1379 1380 err = tcf_chain0_head_change_cb_add(block, ei, extack); 1381 if (err) 1382 goto err_chain0_head_change_cb_add; 1383 1384 err = tcf_block_offload_bind(block, q, ei, extack); 1385 if (err) 1386 goto err_block_offload_bind; 1387 1388 *p_block = block; 1389 return 0; 1390 1391 err_block_offload_bind: 1392 tcf_chain0_head_change_cb_del(block, ei); 1393 err_chain0_head_change_cb_add: 1394 tcf_block_owner_del(block, q, ei->binder_type); 1395 err_block_owner_add: 1396 err_block_insert: 1397 tcf_block_refcnt_put(block, true); 1398 return err; 1399 } 1400 EXPORT_SYMBOL(tcf_block_get_ext); 1401 1402 static void tcf_chain_head_change_dflt(struct tcf_proto *tp_head, void *priv) 1403 { 1404 struct tcf_proto __rcu **p_filter_chain = priv; 1405 1406 rcu_assign_pointer(*p_filter_chain, tp_head); 1407 } 1408 1409 int tcf_block_get(struct tcf_block **p_block, 1410 struct tcf_proto __rcu **p_filter_chain, struct Qdisc *q, 1411 struct netlink_ext_ack *extack) 1412 { 1413 struct tcf_block_ext_info ei = { 1414 .chain_head_change = tcf_chain_head_change_dflt, 1415 .chain_head_change_priv = p_filter_chain, 1416 }; 1417 1418 WARN_ON(!p_filter_chain); 1419 return tcf_block_get_ext(p_block, q, &ei, extack); 1420 } 1421 EXPORT_SYMBOL(tcf_block_get); 1422 1423 /* XXX: Standalone actions are not allowed to jump to any chain, and bound 1424 * actions should be all removed after flushing. 1425 */ 1426 void tcf_block_put_ext(struct tcf_block *block, struct Qdisc *q, 1427 struct tcf_block_ext_info *ei) 1428 { 1429 if (!block) 1430 return; 1431 tcf_chain0_head_change_cb_del(block, ei); 1432 tcf_block_owner_del(block, q, ei->binder_type); 1433 1434 __tcf_block_put(block, q, ei, true); 1435 } 1436 EXPORT_SYMBOL(tcf_block_put_ext); 1437 1438 void tcf_block_put(struct tcf_block *block) 1439 { 1440 struct tcf_block_ext_info ei = {0, }; 1441 1442 if (!block) 1443 return; 1444 tcf_block_put_ext(block, block->q, &ei); 1445 } 1446 1447 EXPORT_SYMBOL(tcf_block_put); 1448 1449 static int 1450 tcf_block_playback_offloads(struct tcf_block *block, flow_setup_cb_t *cb, 1451 void *cb_priv, bool add, bool offload_in_use, 1452 struct netlink_ext_ack *extack) 1453 { 1454 struct tcf_chain *chain, *chain_prev; 1455 struct tcf_proto *tp, *tp_prev; 1456 int err; 1457 1458 lockdep_assert_held(&block->cb_lock); 1459 1460 for (chain = __tcf_get_next_chain(block, NULL); 1461 chain; 1462 chain_prev = chain, 1463 chain = __tcf_get_next_chain(block, chain), 1464 tcf_chain_put(chain_prev)) { 1465 for (tp = __tcf_get_next_proto(chain, NULL); tp; 1466 tp_prev = tp, 1467 tp = __tcf_get_next_proto(chain, tp), 1468 tcf_proto_put(tp_prev, true, NULL)) { 1469 if (tp->ops->reoffload) { 1470 err = tp->ops->reoffload(tp, add, cb, cb_priv, 1471 extack); 1472 if (err && add) 1473 goto err_playback_remove; 1474 } else if (add && offload_in_use) { 1475 err = -EOPNOTSUPP; 1476 NL_SET_ERR_MSG(extack, "Filter HW offload failed - classifier without re-offloading support"); 1477 goto err_playback_remove; 1478 } 1479 } 1480 } 1481 1482 return 0; 1483 1484 err_playback_remove: 1485 tcf_proto_put(tp, true, NULL); 1486 tcf_chain_put(chain); 1487 tcf_block_playback_offloads(block, cb, cb_priv, false, offload_in_use, 1488 extack); 1489 return err; 1490 } 1491 1492 static int tcf_block_bind(struct tcf_block *block, 1493 struct flow_block_offload *bo) 1494 { 1495 struct flow_block_cb *block_cb, *next; 1496 int err, i = 0; 1497 1498 lockdep_assert_held(&block->cb_lock); 1499 1500 list_for_each_entry(block_cb, &bo->cb_list, list) { 1501 err = tcf_block_playback_offloads(block, block_cb->cb, 1502 block_cb->cb_priv, true, 1503 tcf_block_offload_in_use(block), 1504 bo->extack); 1505 if (err) 1506 goto err_unroll; 1507 if (!bo->unlocked_driver_cb) 1508 block->lockeddevcnt++; 1509 1510 i++; 1511 } 1512 list_splice(&bo->cb_list, &block->flow_block.cb_list); 1513 1514 return 0; 1515 1516 err_unroll: 1517 list_for_each_entry_safe(block_cb, next, &bo->cb_list, list) { 1518 if (i-- > 0) { 1519 list_del(&block_cb->list); 1520 tcf_block_playback_offloads(block, block_cb->cb, 1521 block_cb->cb_priv, false, 1522 tcf_block_offload_in_use(block), 1523 NULL); 1524 if (!bo->unlocked_driver_cb) 1525 block->lockeddevcnt--; 1526 } 1527 flow_block_cb_free(block_cb); 1528 } 1529 1530 return err; 1531 } 1532 1533 static void tcf_block_unbind(struct tcf_block *block, 1534 struct flow_block_offload *bo) 1535 { 1536 struct flow_block_cb *block_cb, *next; 1537 1538 lockdep_assert_held(&block->cb_lock); 1539 1540 list_for_each_entry_safe(block_cb, next, &bo->cb_list, list) { 1541 tcf_block_playback_offloads(block, block_cb->cb, 1542 block_cb->cb_priv, false, 1543 tcf_block_offload_in_use(block), 1544 NULL); 1545 list_del(&block_cb->list); 1546 flow_block_cb_free(block_cb); 1547 if (!bo->unlocked_driver_cb) 1548 block->lockeddevcnt--; 1549 } 1550 } 1551 1552 static int tcf_block_setup(struct tcf_block *block, 1553 struct flow_block_offload *bo) 1554 { 1555 int err; 1556 1557 switch (bo->command) { 1558 case FLOW_BLOCK_BIND: 1559 err = tcf_block_bind(block, bo); 1560 break; 1561 case FLOW_BLOCK_UNBIND: 1562 err = 0; 1563 tcf_block_unbind(block, bo); 1564 break; 1565 default: 1566 WARN_ON_ONCE(1); 1567 err = -EOPNOTSUPP; 1568 } 1569 1570 return err; 1571 } 1572 1573 /* Main classifier routine: scans classifier chain attached 1574 * to this qdisc, (optionally) tests for protocol and asks 1575 * specific classifiers. 1576 */ 1577 static inline int __tcf_classify(struct sk_buff *skb, 1578 const struct tcf_proto *tp, 1579 const struct tcf_proto *orig_tp, 1580 struct tcf_result *res, 1581 bool compat_mode, 1582 u32 *last_executed_chain) 1583 { 1584 #ifdef CONFIG_NET_CLS_ACT 1585 const int max_reclassify_loop = 4; 1586 const struct tcf_proto *first_tp; 1587 int limit = 0; 1588 1589 reclassify: 1590 #endif 1591 for (; tp; tp = rcu_dereference_bh(tp->next)) { 1592 __be16 protocol = tc_skb_protocol(skb); 1593 int err; 1594 1595 if (tp->protocol != protocol && 1596 tp->protocol != htons(ETH_P_ALL)) 1597 continue; 1598 1599 err = tp->classify(skb, tp, res); 1600 #ifdef CONFIG_NET_CLS_ACT 1601 if (unlikely(err == TC_ACT_RECLASSIFY && !compat_mode)) { 1602 first_tp = orig_tp; 1603 *last_executed_chain = first_tp->chain->index; 1604 goto reset; 1605 } else if (unlikely(TC_ACT_EXT_CMP(err, TC_ACT_GOTO_CHAIN))) { 1606 first_tp = res->goto_tp; 1607 *last_executed_chain = err & TC_ACT_EXT_VAL_MASK; 1608 goto reset; 1609 } 1610 #endif 1611 if (err >= 0) 1612 return err; 1613 } 1614 1615 return TC_ACT_UNSPEC; /* signal: continue lookup */ 1616 #ifdef CONFIG_NET_CLS_ACT 1617 reset: 1618 if (unlikely(limit++ >= max_reclassify_loop)) { 1619 net_notice_ratelimited("%u: reclassify loop, rule prio %u, protocol %02x\n", 1620 tp->chain->block->index, 1621 tp->prio & 0xffff, 1622 ntohs(tp->protocol)); 1623 return TC_ACT_SHOT; 1624 } 1625 1626 tp = first_tp; 1627 goto reclassify; 1628 #endif 1629 } 1630 1631 int tcf_classify(struct sk_buff *skb, const struct tcf_proto *tp, 1632 struct tcf_result *res, bool compat_mode) 1633 { 1634 u32 last_executed_chain = 0; 1635 1636 return __tcf_classify(skb, tp, tp, res, compat_mode, 1637 &last_executed_chain); 1638 } 1639 EXPORT_SYMBOL(tcf_classify); 1640 1641 int tcf_classify_ingress(struct sk_buff *skb, 1642 const struct tcf_block *ingress_block, 1643 const struct tcf_proto *tp, 1644 struct tcf_result *res, bool compat_mode) 1645 { 1646 #if !IS_ENABLED(CONFIG_NET_TC_SKB_EXT) 1647 u32 last_executed_chain = 0; 1648 1649 return __tcf_classify(skb, tp, tp, res, compat_mode, 1650 &last_executed_chain); 1651 #else 1652 u32 last_executed_chain = tp ? tp->chain->index : 0; 1653 const struct tcf_proto *orig_tp = tp; 1654 struct tc_skb_ext *ext; 1655 int ret; 1656 1657 ext = skb_ext_find(skb, TC_SKB_EXT); 1658 1659 if (ext && ext->chain) { 1660 struct tcf_chain *fchain; 1661 1662 fchain = tcf_chain_lookup_rcu(ingress_block, ext->chain); 1663 if (!fchain) 1664 return TC_ACT_SHOT; 1665 1666 /* Consume, so cloned/redirect skbs won't inherit ext */ 1667 skb_ext_del(skb, TC_SKB_EXT); 1668 1669 tp = rcu_dereference_bh(fchain->filter_chain); 1670 } 1671 1672 ret = __tcf_classify(skb, tp, orig_tp, res, compat_mode, 1673 &last_executed_chain); 1674 1675 /* If we missed on some chain */ 1676 if (ret == TC_ACT_UNSPEC && last_executed_chain) { 1677 ext = skb_ext_add(skb, TC_SKB_EXT); 1678 if (WARN_ON_ONCE(!ext)) 1679 return TC_ACT_SHOT; 1680 ext->chain = last_executed_chain; 1681 } 1682 1683 return ret; 1684 #endif 1685 } 1686 EXPORT_SYMBOL(tcf_classify_ingress); 1687 1688 struct tcf_chain_info { 1689 struct tcf_proto __rcu **pprev; 1690 struct tcf_proto __rcu *next; 1691 }; 1692 1693 static struct tcf_proto *tcf_chain_tp_prev(struct tcf_chain *chain, 1694 struct tcf_chain_info *chain_info) 1695 { 1696 return tcf_chain_dereference(*chain_info->pprev, chain); 1697 } 1698 1699 static int tcf_chain_tp_insert(struct tcf_chain *chain, 1700 struct tcf_chain_info *chain_info, 1701 struct tcf_proto *tp) 1702 { 1703 if (chain->flushing) 1704 return -EAGAIN; 1705 1706 if (*chain_info->pprev == chain->filter_chain) 1707 tcf_chain0_head_change(chain, tp); 1708 tcf_proto_get(tp); 1709 RCU_INIT_POINTER(tp->next, tcf_chain_tp_prev(chain, chain_info)); 1710 rcu_assign_pointer(*chain_info->pprev, tp); 1711 1712 return 0; 1713 } 1714 1715 static void tcf_chain_tp_remove(struct tcf_chain *chain, 1716 struct tcf_chain_info *chain_info, 1717 struct tcf_proto *tp) 1718 { 1719 struct tcf_proto *next = tcf_chain_dereference(chain_info->next, chain); 1720 1721 tcf_proto_mark_delete(tp); 1722 if (tp == chain->filter_chain) 1723 tcf_chain0_head_change(chain, next); 1724 RCU_INIT_POINTER(*chain_info->pprev, next); 1725 } 1726 1727 static struct tcf_proto *tcf_chain_tp_find(struct tcf_chain *chain, 1728 struct tcf_chain_info *chain_info, 1729 u32 protocol, u32 prio, 1730 bool prio_allocate); 1731 1732 /* Try to insert new proto. 1733 * If proto with specified priority already exists, free new proto 1734 * and return existing one. 1735 */ 1736 1737 static struct tcf_proto *tcf_chain_tp_insert_unique(struct tcf_chain *chain, 1738 struct tcf_proto *tp_new, 1739 u32 protocol, u32 prio, 1740 bool rtnl_held) 1741 { 1742 struct tcf_chain_info chain_info; 1743 struct tcf_proto *tp; 1744 int err = 0; 1745 1746 mutex_lock(&chain->filter_chain_lock); 1747 1748 if (tcf_proto_exists_destroying(chain, tp_new)) { 1749 mutex_unlock(&chain->filter_chain_lock); 1750 tcf_proto_destroy(tp_new, rtnl_held, false, NULL); 1751 return ERR_PTR(-EAGAIN); 1752 } 1753 1754 tp = tcf_chain_tp_find(chain, &chain_info, 1755 protocol, prio, false); 1756 if (!tp) 1757 err = tcf_chain_tp_insert(chain, &chain_info, tp_new); 1758 mutex_unlock(&chain->filter_chain_lock); 1759 1760 if (tp) { 1761 tcf_proto_destroy(tp_new, rtnl_held, false, NULL); 1762 tp_new = tp; 1763 } else if (err) { 1764 tcf_proto_destroy(tp_new, rtnl_held, false, NULL); 1765 tp_new = ERR_PTR(err); 1766 } 1767 1768 return tp_new; 1769 } 1770 1771 static void tcf_chain_tp_delete_empty(struct tcf_chain *chain, 1772 struct tcf_proto *tp, bool rtnl_held, 1773 struct netlink_ext_ack *extack) 1774 { 1775 struct tcf_chain_info chain_info; 1776 struct tcf_proto *tp_iter; 1777 struct tcf_proto **pprev; 1778 struct tcf_proto *next; 1779 1780 mutex_lock(&chain->filter_chain_lock); 1781 1782 /* Atomically find and remove tp from chain. */ 1783 for (pprev = &chain->filter_chain; 1784 (tp_iter = tcf_chain_dereference(*pprev, chain)); 1785 pprev = &tp_iter->next) { 1786 if (tp_iter == tp) { 1787 chain_info.pprev = pprev; 1788 chain_info.next = tp_iter->next; 1789 WARN_ON(tp_iter->deleting); 1790 break; 1791 } 1792 } 1793 /* Verify that tp still exists and no new filters were inserted 1794 * concurrently. 1795 * Mark tp for deletion if it is empty. 1796 */ 1797 if (!tp_iter || !tcf_proto_check_delete(tp)) { 1798 mutex_unlock(&chain->filter_chain_lock); 1799 return; 1800 } 1801 1802 tcf_proto_signal_destroying(chain, tp); 1803 next = tcf_chain_dereference(chain_info.next, chain); 1804 if (tp == chain->filter_chain) 1805 tcf_chain0_head_change(chain, next); 1806 RCU_INIT_POINTER(*chain_info.pprev, next); 1807 mutex_unlock(&chain->filter_chain_lock); 1808 1809 tcf_proto_put(tp, rtnl_held, extack); 1810 } 1811 1812 static struct tcf_proto *tcf_chain_tp_find(struct tcf_chain *chain, 1813 struct tcf_chain_info *chain_info, 1814 u32 protocol, u32 prio, 1815 bool prio_allocate) 1816 { 1817 struct tcf_proto **pprev; 1818 struct tcf_proto *tp; 1819 1820 /* Check the chain for existence of proto-tcf with this priority */ 1821 for (pprev = &chain->filter_chain; 1822 (tp = tcf_chain_dereference(*pprev, chain)); 1823 pprev = &tp->next) { 1824 if (tp->prio >= prio) { 1825 if (tp->prio == prio) { 1826 if (prio_allocate || 1827 (tp->protocol != protocol && protocol)) 1828 return ERR_PTR(-EINVAL); 1829 } else { 1830 tp = NULL; 1831 } 1832 break; 1833 } 1834 } 1835 chain_info->pprev = pprev; 1836 if (tp) { 1837 chain_info->next = tp->next; 1838 tcf_proto_get(tp); 1839 } else { 1840 chain_info->next = NULL; 1841 } 1842 return tp; 1843 } 1844 1845 static int tcf_fill_node(struct net *net, struct sk_buff *skb, 1846 struct tcf_proto *tp, struct tcf_block *block, 1847 struct Qdisc *q, u32 parent, void *fh, 1848 u32 portid, u32 seq, u16 flags, int event, 1849 bool rtnl_held) 1850 { 1851 struct tcmsg *tcm; 1852 struct nlmsghdr *nlh; 1853 unsigned char *b = skb_tail_pointer(skb); 1854 1855 nlh = nlmsg_put(skb, portid, seq, event, sizeof(*tcm), flags); 1856 if (!nlh) 1857 goto out_nlmsg_trim; 1858 tcm = nlmsg_data(nlh); 1859 tcm->tcm_family = AF_UNSPEC; 1860 tcm->tcm__pad1 = 0; 1861 tcm->tcm__pad2 = 0; 1862 if (q) { 1863 tcm->tcm_ifindex = qdisc_dev(q)->ifindex; 1864 tcm->tcm_parent = parent; 1865 } else { 1866 tcm->tcm_ifindex = TCM_IFINDEX_MAGIC_BLOCK; 1867 tcm->tcm_block_index = block->index; 1868 } 1869 tcm->tcm_info = TC_H_MAKE(tp->prio, tp->protocol); 1870 if (nla_put_string(skb, TCA_KIND, tp->ops->kind)) 1871 goto nla_put_failure; 1872 if (nla_put_u32(skb, TCA_CHAIN, tp->chain->index)) 1873 goto nla_put_failure; 1874 if (!fh) { 1875 tcm->tcm_handle = 0; 1876 } else { 1877 if (tp->ops->dump && 1878 tp->ops->dump(net, tp, fh, skb, tcm, rtnl_held) < 0) 1879 goto nla_put_failure; 1880 } 1881 nlh->nlmsg_len = skb_tail_pointer(skb) - b; 1882 return skb->len; 1883 1884 out_nlmsg_trim: 1885 nla_put_failure: 1886 nlmsg_trim(skb, b); 1887 return -1; 1888 } 1889 1890 static int tfilter_notify(struct net *net, struct sk_buff *oskb, 1891 struct nlmsghdr *n, struct tcf_proto *tp, 1892 struct tcf_block *block, struct Qdisc *q, 1893 u32 parent, void *fh, int event, bool unicast, 1894 bool rtnl_held) 1895 { 1896 struct sk_buff *skb; 1897 u32 portid = oskb ? NETLINK_CB(oskb).portid : 0; 1898 int err = 0; 1899 1900 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL); 1901 if (!skb) 1902 return -ENOBUFS; 1903 1904 if (tcf_fill_node(net, skb, tp, block, q, parent, fh, portid, 1905 n->nlmsg_seq, n->nlmsg_flags, event, 1906 rtnl_held) <= 0) { 1907 kfree_skb(skb); 1908 return -EINVAL; 1909 } 1910 1911 if (unicast) 1912 err = netlink_unicast(net->rtnl, skb, portid, MSG_DONTWAIT); 1913 else 1914 err = rtnetlink_send(skb, net, portid, RTNLGRP_TC, 1915 n->nlmsg_flags & NLM_F_ECHO); 1916 1917 if (err > 0) 1918 err = 0; 1919 return err; 1920 } 1921 1922 static int tfilter_del_notify(struct net *net, struct sk_buff *oskb, 1923 struct nlmsghdr *n, struct tcf_proto *tp, 1924 struct tcf_block *block, struct Qdisc *q, 1925 u32 parent, void *fh, bool unicast, bool *last, 1926 bool rtnl_held, struct netlink_ext_ack *extack) 1927 { 1928 struct sk_buff *skb; 1929 u32 portid = oskb ? NETLINK_CB(oskb).portid : 0; 1930 int err; 1931 1932 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL); 1933 if (!skb) 1934 return -ENOBUFS; 1935 1936 if (tcf_fill_node(net, skb, tp, block, q, parent, fh, portid, 1937 n->nlmsg_seq, n->nlmsg_flags, RTM_DELTFILTER, 1938 rtnl_held) <= 0) { 1939 NL_SET_ERR_MSG(extack, "Failed to build del event notification"); 1940 kfree_skb(skb); 1941 return -EINVAL; 1942 } 1943 1944 err = tp->ops->delete(tp, fh, last, rtnl_held, extack); 1945 if (err) { 1946 kfree_skb(skb); 1947 return err; 1948 } 1949 1950 if (unicast) 1951 err = netlink_unicast(net->rtnl, skb, portid, MSG_DONTWAIT); 1952 else 1953 err = rtnetlink_send(skb, net, portid, RTNLGRP_TC, 1954 n->nlmsg_flags & NLM_F_ECHO); 1955 if (err < 0) 1956 NL_SET_ERR_MSG(extack, "Failed to send filter delete notification"); 1957 1958 if (err > 0) 1959 err = 0; 1960 return err; 1961 } 1962 1963 static void tfilter_notify_chain(struct net *net, struct sk_buff *oskb, 1964 struct tcf_block *block, struct Qdisc *q, 1965 u32 parent, struct nlmsghdr *n, 1966 struct tcf_chain *chain, int event, 1967 bool rtnl_held) 1968 { 1969 struct tcf_proto *tp; 1970 1971 for (tp = tcf_get_next_proto(chain, NULL, rtnl_held); 1972 tp; tp = tcf_get_next_proto(chain, tp, rtnl_held)) 1973 tfilter_notify(net, oskb, n, tp, block, 1974 q, parent, NULL, event, false, rtnl_held); 1975 } 1976 1977 static void tfilter_put(struct tcf_proto *tp, void *fh) 1978 { 1979 if (tp->ops->put && fh) 1980 tp->ops->put(tp, fh); 1981 } 1982 1983 static int tc_new_tfilter(struct sk_buff *skb, struct nlmsghdr *n, 1984 struct netlink_ext_ack *extack) 1985 { 1986 struct net *net = sock_net(skb->sk); 1987 struct nlattr *tca[TCA_MAX + 1]; 1988 char name[IFNAMSIZ]; 1989 struct tcmsg *t; 1990 u32 protocol; 1991 u32 prio; 1992 bool prio_allocate; 1993 u32 parent; 1994 u32 chain_index; 1995 struct Qdisc *q = NULL; 1996 struct tcf_chain_info chain_info; 1997 struct tcf_chain *chain = NULL; 1998 struct tcf_block *block; 1999 struct tcf_proto *tp; 2000 unsigned long cl; 2001 void *fh; 2002 int err; 2003 int tp_created; 2004 bool rtnl_held = false; 2005 2006 if (!netlink_ns_capable(skb, net->user_ns, CAP_NET_ADMIN)) 2007 return -EPERM; 2008 2009 replay: 2010 tp_created = 0; 2011 2012 err = nlmsg_parse_deprecated(n, sizeof(*t), tca, TCA_MAX, 2013 rtm_tca_policy, extack); 2014 if (err < 0) 2015 return err; 2016 2017 t = nlmsg_data(n); 2018 protocol = TC_H_MIN(t->tcm_info); 2019 prio = TC_H_MAJ(t->tcm_info); 2020 prio_allocate = false; 2021 parent = t->tcm_parent; 2022 tp = NULL; 2023 cl = 0; 2024 block = NULL; 2025 2026 if (prio == 0) { 2027 /* If no priority is provided by the user, 2028 * we allocate one. 2029 */ 2030 if (n->nlmsg_flags & NLM_F_CREATE) { 2031 prio = TC_H_MAKE(0x80000000U, 0U); 2032 prio_allocate = true; 2033 } else { 2034 NL_SET_ERR_MSG(extack, "Invalid filter command with priority of zero"); 2035 return -ENOENT; 2036 } 2037 } 2038 2039 /* Find head of filter chain. */ 2040 2041 err = __tcf_qdisc_find(net, &q, &parent, t->tcm_ifindex, false, extack); 2042 if (err) 2043 return err; 2044 2045 if (tcf_proto_check_kind(tca[TCA_KIND], name)) { 2046 NL_SET_ERR_MSG(extack, "Specified TC filter name too long"); 2047 err = -EINVAL; 2048 goto errout; 2049 } 2050 2051 /* Take rtnl mutex if rtnl_held was set to true on previous iteration, 2052 * block is shared (no qdisc found), qdisc is not unlocked, classifier 2053 * type is not specified, classifier is not unlocked. 2054 */ 2055 if (rtnl_held || 2056 (q && !(q->ops->cl_ops->flags & QDISC_CLASS_OPS_DOIT_UNLOCKED)) || 2057 !tcf_proto_is_unlocked(name)) { 2058 rtnl_held = true; 2059 rtnl_lock(); 2060 } 2061 2062 err = __tcf_qdisc_cl_find(q, parent, &cl, t->tcm_ifindex, extack); 2063 if (err) 2064 goto errout; 2065 2066 block = __tcf_block_find(net, q, cl, t->tcm_ifindex, t->tcm_block_index, 2067 extack); 2068 if (IS_ERR(block)) { 2069 err = PTR_ERR(block); 2070 goto errout; 2071 } 2072 2073 chain_index = tca[TCA_CHAIN] ? nla_get_u32(tca[TCA_CHAIN]) : 0; 2074 if (chain_index > TC_ACT_EXT_VAL_MASK) { 2075 NL_SET_ERR_MSG(extack, "Specified chain index exceeds upper limit"); 2076 err = -EINVAL; 2077 goto errout; 2078 } 2079 chain = tcf_chain_get(block, chain_index, true); 2080 if (!chain) { 2081 NL_SET_ERR_MSG(extack, "Cannot create specified filter chain"); 2082 err = -ENOMEM; 2083 goto errout; 2084 } 2085 2086 mutex_lock(&chain->filter_chain_lock); 2087 tp = tcf_chain_tp_find(chain, &chain_info, protocol, 2088 prio, prio_allocate); 2089 if (IS_ERR(tp)) { 2090 NL_SET_ERR_MSG(extack, "Filter with specified priority/protocol not found"); 2091 err = PTR_ERR(tp); 2092 goto errout_locked; 2093 } 2094 2095 if (tp == NULL) { 2096 struct tcf_proto *tp_new = NULL; 2097 2098 if (chain->flushing) { 2099 err = -EAGAIN; 2100 goto errout_locked; 2101 } 2102 2103 /* Proto-tcf does not exist, create new one */ 2104 2105 if (tca[TCA_KIND] == NULL || !protocol) { 2106 NL_SET_ERR_MSG(extack, "Filter kind and protocol must be specified"); 2107 err = -EINVAL; 2108 goto errout_locked; 2109 } 2110 2111 if (!(n->nlmsg_flags & NLM_F_CREATE)) { 2112 NL_SET_ERR_MSG(extack, "Need both RTM_NEWTFILTER and NLM_F_CREATE to create a new filter"); 2113 err = -ENOENT; 2114 goto errout_locked; 2115 } 2116 2117 if (prio_allocate) 2118 prio = tcf_auto_prio(tcf_chain_tp_prev(chain, 2119 &chain_info)); 2120 2121 mutex_unlock(&chain->filter_chain_lock); 2122 tp_new = tcf_proto_create(name, protocol, prio, chain, 2123 rtnl_held, extack); 2124 if (IS_ERR(tp_new)) { 2125 err = PTR_ERR(tp_new); 2126 goto errout_tp; 2127 } 2128 2129 tp_created = 1; 2130 tp = tcf_chain_tp_insert_unique(chain, tp_new, protocol, prio, 2131 rtnl_held); 2132 if (IS_ERR(tp)) { 2133 err = PTR_ERR(tp); 2134 goto errout_tp; 2135 } 2136 } else { 2137 mutex_unlock(&chain->filter_chain_lock); 2138 } 2139 2140 if (tca[TCA_KIND] && nla_strcmp(tca[TCA_KIND], tp->ops->kind)) { 2141 NL_SET_ERR_MSG(extack, "Specified filter kind does not match existing one"); 2142 err = -EINVAL; 2143 goto errout; 2144 } 2145 2146 fh = tp->ops->get(tp, t->tcm_handle); 2147 2148 if (!fh) { 2149 if (!(n->nlmsg_flags & NLM_F_CREATE)) { 2150 NL_SET_ERR_MSG(extack, "Need both RTM_NEWTFILTER and NLM_F_CREATE to create a new filter"); 2151 err = -ENOENT; 2152 goto errout; 2153 } 2154 } else if (n->nlmsg_flags & NLM_F_EXCL) { 2155 tfilter_put(tp, fh); 2156 NL_SET_ERR_MSG(extack, "Filter already exists"); 2157 err = -EEXIST; 2158 goto errout; 2159 } 2160 2161 if (chain->tmplt_ops && chain->tmplt_ops != tp->ops) { 2162 NL_SET_ERR_MSG(extack, "Chain template is set to a different filter kind"); 2163 err = -EINVAL; 2164 goto errout; 2165 } 2166 2167 err = tp->ops->change(net, skb, tp, cl, t->tcm_handle, tca, &fh, 2168 n->nlmsg_flags & NLM_F_CREATE ? TCA_ACT_NOREPLACE : TCA_ACT_REPLACE, 2169 rtnl_held, extack); 2170 if (err == 0) { 2171 tfilter_notify(net, skb, n, tp, block, q, parent, fh, 2172 RTM_NEWTFILTER, false, rtnl_held); 2173 tfilter_put(tp, fh); 2174 /* q pointer is NULL for shared blocks */ 2175 if (q) 2176 q->flags &= ~TCQ_F_CAN_BYPASS; 2177 } 2178 2179 errout: 2180 if (err && tp_created) 2181 tcf_chain_tp_delete_empty(chain, tp, rtnl_held, NULL); 2182 errout_tp: 2183 if (chain) { 2184 if (tp && !IS_ERR(tp)) 2185 tcf_proto_put(tp, rtnl_held, NULL); 2186 if (!tp_created) 2187 tcf_chain_put(chain); 2188 } 2189 tcf_block_release(q, block, rtnl_held); 2190 2191 if (rtnl_held) 2192 rtnl_unlock(); 2193 2194 if (err == -EAGAIN) { 2195 /* Take rtnl lock in case EAGAIN is caused by concurrent flush 2196 * of target chain. 2197 */ 2198 rtnl_held = true; 2199 /* Replay the request. */ 2200 goto replay; 2201 } 2202 return err; 2203 2204 errout_locked: 2205 mutex_unlock(&chain->filter_chain_lock); 2206 goto errout; 2207 } 2208 2209 static int tc_del_tfilter(struct sk_buff *skb, struct nlmsghdr *n, 2210 struct netlink_ext_ack *extack) 2211 { 2212 struct net *net = sock_net(skb->sk); 2213 struct nlattr *tca[TCA_MAX + 1]; 2214 char name[IFNAMSIZ]; 2215 struct tcmsg *t; 2216 u32 protocol; 2217 u32 prio; 2218 u32 parent; 2219 u32 chain_index; 2220 struct Qdisc *q = NULL; 2221 struct tcf_chain_info chain_info; 2222 struct tcf_chain *chain = NULL; 2223 struct tcf_block *block = NULL; 2224 struct tcf_proto *tp = NULL; 2225 unsigned long cl = 0; 2226 void *fh = NULL; 2227 int err; 2228 bool rtnl_held = false; 2229 2230 if (!netlink_ns_capable(skb, net->user_ns, CAP_NET_ADMIN)) 2231 return -EPERM; 2232 2233 err = nlmsg_parse_deprecated(n, sizeof(*t), tca, TCA_MAX, 2234 rtm_tca_policy, extack); 2235 if (err < 0) 2236 return err; 2237 2238 t = nlmsg_data(n); 2239 protocol = TC_H_MIN(t->tcm_info); 2240 prio = TC_H_MAJ(t->tcm_info); 2241 parent = t->tcm_parent; 2242 2243 if (prio == 0 && (protocol || t->tcm_handle || tca[TCA_KIND])) { 2244 NL_SET_ERR_MSG(extack, "Cannot flush filters with protocol, handle or kind set"); 2245 return -ENOENT; 2246 } 2247 2248 /* Find head of filter chain. */ 2249 2250 err = __tcf_qdisc_find(net, &q, &parent, t->tcm_ifindex, false, extack); 2251 if (err) 2252 return err; 2253 2254 if (tcf_proto_check_kind(tca[TCA_KIND], name)) { 2255 NL_SET_ERR_MSG(extack, "Specified TC filter name too long"); 2256 err = -EINVAL; 2257 goto errout; 2258 } 2259 /* Take rtnl mutex if flushing whole chain, block is shared (no qdisc 2260 * found), qdisc is not unlocked, classifier type is not specified, 2261 * classifier is not unlocked. 2262 */ 2263 if (!prio || 2264 (q && !(q->ops->cl_ops->flags & QDISC_CLASS_OPS_DOIT_UNLOCKED)) || 2265 !tcf_proto_is_unlocked(name)) { 2266 rtnl_held = true; 2267 rtnl_lock(); 2268 } 2269 2270 err = __tcf_qdisc_cl_find(q, parent, &cl, t->tcm_ifindex, extack); 2271 if (err) 2272 goto errout; 2273 2274 block = __tcf_block_find(net, q, cl, t->tcm_ifindex, t->tcm_block_index, 2275 extack); 2276 if (IS_ERR(block)) { 2277 err = PTR_ERR(block); 2278 goto errout; 2279 } 2280 2281 chain_index = tca[TCA_CHAIN] ? nla_get_u32(tca[TCA_CHAIN]) : 0; 2282 if (chain_index > TC_ACT_EXT_VAL_MASK) { 2283 NL_SET_ERR_MSG(extack, "Specified chain index exceeds upper limit"); 2284 err = -EINVAL; 2285 goto errout; 2286 } 2287 chain = tcf_chain_get(block, chain_index, false); 2288 if (!chain) { 2289 /* User requested flush on non-existent chain. Nothing to do, 2290 * so just return success. 2291 */ 2292 if (prio == 0) { 2293 err = 0; 2294 goto errout; 2295 } 2296 NL_SET_ERR_MSG(extack, "Cannot find specified filter chain"); 2297 err = -ENOENT; 2298 goto errout; 2299 } 2300 2301 if (prio == 0) { 2302 tfilter_notify_chain(net, skb, block, q, parent, n, 2303 chain, RTM_DELTFILTER, rtnl_held); 2304 tcf_chain_flush(chain, rtnl_held); 2305 err = 0; 2306 goto errout; 2307 } 2308 2309 mutex_lock(&chain->filter_chain_lock); 2310 tp = tcf_chain_tp_find(chain, &chain_info, protocol, 2311 prio, false); 2312 if (!tp || IS_ERR(tp)) { 2313 NL_SET_ERR_MSG(extack, "Filter with specified priority/protocol not found"); 2314 err = tp ? PTR_ERR(tp) : -ENOENT; 2315 goto errout_locked; 2316 } else if (tca[TCA_KIND] && nla_strcmp(tca[TCA_KIND], tp->ops->kind)) { 2317 NL_SET_ERR_MSG(extack, "Specified filter kind does not match existing one"); 2318 err = -EINVAL; 2319 goto errout_locked; 2320 } else if (t->tcm_handle == 0) { 2321 tcf_proto_signal_destroying(chain, tp); 2322 tcf_chain_tp_remove(chain, &chain_info, tp); 2323 mutex_unlock(&chain->filter_chain_lock); 2324 2325 tcf_proto_put(tp, rtnl_held, NULL); 2326 tfilter_notify(net, skb, n, tp, block, q, parent, fh, 2327 RTM_DELTFILTER, false, rtnl_held); 2328 err = 0; 2329 goto errout; 2330 } 2331 mutex_unlock(&chain->filter_chain_lock); 2332 2333 fh = tp->ops->get(tp, t->tcm_handle); 2334 2335 if (!fh) { 2336 NL_SET_ERR_MSG(extack, "Specified filter handle not found"); 2337 err = -ENOENT; 2338 } else { 2339 bool last; 2340 2341 err = tfilter_del_notify(net, skb, n, tp, block, 2342 q, parent, fh, false, &last, 2343 rtnl_held, extack); 2344 2345 if (err) 2346 goto errout; 2347 if (last) 2348 tcf_chain_tp_delete_empty(chain, tp, rtnl_held, extack); 2349 } 2350 2351 errout: 2352 if (chain) { 2353 if (tp && !IS_ERR(tp)) 2354 tcf_proto_put(tp, rtnl_held, NULL); 2355 tcf_chain_put(chain); 2356 } 2357 tcf_block_release(q, block, rtnl_held); 2358 2359 if (rtnl_held) 2360 rtnl_unlock(); 2361 2362 return err; 2363 2364 errout_locked: 2365 mutex_unlock(&chain->filter_chain_lock); 2366 goto errout; 2367 } 2368 2369 static int tc_get_tfilter(struct sk_buff *skb, struct nlmsghdr *n, 2370 struct netlink_ext_ack *extack) 2371 { 2372 struct net *net = sock_net(skb->sk); 2373 struct nlattr *tca[TCA_MAX + 1]; 2374 char name[IFNAMSIZ]; 2375 struct tcmsg *t; 2376 u32 protocol; 2377 u32 prio; 2378 u32 parent; 2379 u32 chain_index; 2380 struct Qdisc *q = NULL; 2381 struct tcf_chain_info chain_info; 2382 struct tcf_chain *chain = NULL; 2383 struct tcf_block *block = NULL; 2384 struct tcf_proto *tp = NULL; 2385 unsigned long cl = 0; 2386 void *fh = NULL; 2387 int err; 2388 bool rtnl_held = false; 2389 2390 err = nlmsg_parse_deprecated(n, sizeof(*t), tca, TCA_MAX, 2391 rtm_tca_policy, extack); 2392 if (err < 0) 2393 return err; 2394 2395 t = nlmsg_data(n); 2396 protocol = TC_H_MIN(t->tcm_info); 2397 prio = TC_H_MAJ(t->tcm_info); 2398 parent = t->tcm_parent; 2399 2400 if (prio == 0) { 2401 NL_SET_ERR_MSG(extack, "Invalid filter command with priority of zero"); 2402 return -ENOENT; 2403 } 2404 2405 /* Find head of filter chain. */ 2406 2407 err = __tcf_qdisc_find(net, &q, &parent, t->tcm_ifindex, false, extack); 2408 if (err) 2409 return err; 2410 2411 if (tcf_proto_check_kind(tca[TCA_KIND], name)) { 2412 NL_SET_ERR_MSG(extack, "Specified TC filter name too long"); 2413 err = -EINVAL; 2414 goto errout; 2415 } 2416 /* Take rtnl mutex if block is shared (no qdisc found), qdisc is not 2417 * unlocked, classifier type is not specified, classifier is not 2418 * unlocked. 2419 */ 2420 if ((q && !(q->ops->cl_ops->flags & QDISC_CLASS_OPS_DOIT_UNLOCKED)) || 2421 !tcf_proto_is_unlocked(name)) { 2422 rtnl_held = true; 2423 rtnl_lock(); 2424 } 2425 2426 err = __tcf_qdisc_cl_find(q, parent, &cl, t->tcm_ifindex, extack); 2427 if (err) 2428 goto errout; 2429 2430 block = __tcf_block_find(net, q, cl, t->tcm_ifindex, t->tcm_block_index, 2431 extack); 2432 if (IS_ERR(block)) { 2433 err = PTR_ERR(block); 2434 goto errout; 2435 } 2436 2437 chain_index = tca[TCA_CHAIN] ? nla_get_u32(tca[TCA_CHAIN]) : 0; 2438 if (chain_index > TC_ACT_EXT_VAL_MASK) { 2439 NL_SET_ERR_MSG(extack, "Specified chain index exceeds upper limit"); 2440 err = -EINVAL; 2441 goto errout; 2442 } 2443 chain = tcf_chain_get(block, chain_index, false); 2444 if (!chain) { 2445 NL_SET_ERR_MSG(extack, "Cannot find specified filter chain"); 2446 err = -EINVAL; 2447 goto errout; 2448 } 2449 2450 mutex_lock(&chain->filter_chain_lock); 2451 tp = tcf_chain_tp_find(chain, &chain_info, protocol, 2452 prio, false); 2453 mutex_unlock(&chain->filter_chain_lock); 2454 if (!tp || IS_ERR(tp)) { 2455 NL_SET_ERR_MSG(extack, "Filter with specified priority/protocol not found"); 2456 err = tp ? PTR_ERR(tp) : -ENOENT; 2457 goto errout; 2458 } else if (tca[TCA_KIND] && nla_strcmp(tca[TCA_KIND], tp->ops->kind)) { 2459 NL_SET_ERR_MSG(extack, "Specified filter kind does not match existing one"); 2460 err = -EINVAL; 2461 goto errout; 2462 } 2463 2464 fh = tp->ops->get(tp, t->tcm_handle); 2465 2466 if (!fh) { 2467 NL_SET_ERR_MSG(extack, "Specified filter handle not found"); 2468 err = -ENOENT; 2469 } else { 2470 err = tfilter_notify(net, skb, n, tp, block, q, parent, 2471 fh, RTM_NEWTFILTER, true, rtnl_held); 2472 if (err < 0) 2473 NL_SET_ERR_MSG(extack, "Failed to send filter notify message"); 2474 } 2475 2476 tfilter_put(tp, fh); 2477 errout: 2478 if (chain) { 2479 if (tp && !IS_ERR(tp)) 2480 tcf_proto_put(tp, rtnl_held, NULL); 2481 tcf_chain_put(chain); 2482 } 2483 tcf_block_release(q, block, rtnl_held); 2484 2485 if (rtnl_held) 2486 rtnl_unlock(); 2487 2488 return err; 2489 } 2490 2491 struct tcf_dump_args { 2492 struct tcf_walker w; 2493 struct sk_buff *skb; 2494 struct netlink_callback *cb; 2495 struct tcf_block *block; 2496 struct Qdisc *q; 2497 u32 parent; 2498 }; 2499 2500 static int tcf_node_dump(struct tcf_proto *tp, void *n, struct tcf_walker *arg) 2501 { 2502 struct tcf_dump_args *a = (void *)arg; 2503 struct net *net = sock_net(a->skb->sk); 2504 2505 return tcf_fill_node(net, a->skb, tp, a->block, a->q, a->parent, 2506 n, NETLINK_CB(a->cb->skb).portid, 2507 a->cb->nlh->nlmsg_seq, NLM_F_MULTI, 2508 RTM_NEWTFILTER, true); 2509 } 2510 2511 static bool tcf_chain_dump(struct tcf_chain *chain, struct Qdisc *q, u32 parent, 2512 struct sk_buff *skb, struct netlink_callback *cb, 2513 long index_start, long *p_index) 2514 { 2515 struct net *net = sock_net(skb->sk); 2516 struct tcf_block *block = chain->block; 2517 struct tcmsg *tcm = nlmsg_data(cb->nlh); 2518 struct tcf_proto *tp, *tp_prev; 2519 struct tcf_dump_args arg; 2520 2521 for (tp = __tcf_get_next_proto(chain, NULL); 2522 tp; 2523 tp_prev = tp, 2524 tp = __tcf_get_next_proto(chain, tp), 2525 tcf_proto_put(tp_prev, true, NULL), 2526 (*p_index)++) { 2527 if (*p_index < index_start) 2528 continue; 2529 if (TC_H_MAJ(tcm->tcm_info) && 2530 TC_H_MAJ(tcm->tcm_info) != tp->prio) 2531 continue; 2532 if (TC_H_MIN(tcm->tcm_info) && 2533 TC_H_MIN(tcm->tcm_info) != tp->protocol) 2534 continue; 2535 if (*p_index > index_start) 2536 memset(&cb->args[1], 0, 2537 sizeof(cb->args) - sizeof(cb->args[0])); 2538 if (cb->args[1] == 0) { 2539 if (tcf_fill_node(net, skb, tp, block, q, parent, NULL, 2540 NETLINK_CB(cb->skb).portid, 2541 cb->nlh->nlmsg_seq, NLM_F_MULTI, 2542 RTM_NEWTFILTER, true) <= 0) 2543 goto errout; 2544 cb->args[1] = 1; 2545 } 2546 if (!tp->ops->walk) 2547 continue; 2548 arg.w.fn = tcf_node_dump; 2549 arg.skb = skb; 2550 arg.cb = cb; 2551 arg.block = block; 2552 arg.q = q; 2553 arg.parent = parent; 2554 arg.w.stop = 0; 2555 arg.w.skip = cb->args[1] - 1; 2556 arg.w.count = 0; 2557 arg.w.cookie = cb->args[2]; 2558 tp->ops->walk(tp, &arg.w, true); 2559 cb->args[2] = arg.w.cookie; 2560 cb->args[1] = arg.w.count + 1; 2561 if (arg.w.stop) 2562 goto errout; 2563 } 2564 return true; 2565 2566 errout: 2567 tcf_proto_put(tp, true, NULL); 2568 return false; 2569 } 2570 2571 /* called with RTNL */ 2572 static int tc_dump_tfilter(struct sk_buff *skb, struct netlink_callback *cb) 2573 { 2574 struct tcf_chain *chain, *chain_prev; 2575 struct net *net = sock_net(skb->sk); 2576 struct nlattr *tca[TCA_MAX + 1]; 2577 struct Qdisc *q = NULL; 2578 struct tcf_block *block; 2579 struct tcmsg *tcm = nlmsg_data(cb->nlh); 2580 long index_start; 2581 long index; 2582 u32 parent; 2583 int err; 2584 2585 if (nlmsg_len(cb->nlh) < sizeof(*tcm)) 2586 return skb->len; 2587 2588 err = nlmsg_parse_deprecated(cb->nlh, sizeof(*tcm), tca, TCA_MAX, 2589 NULL, cb->extack); 2590 if (err) 2591 return err; 2592 2593 if (tcm->tcm_ifindex == TCM_IFINDEX_MAGIC_BLOCK) { 2594 block = tcf_block_refcnt_get(net, tcm->tcm_block_index); 2595 if (!block) 2596 goto out; 2597 /* If we work with block index, q is NULL and parent value 2598 * will never be used in the following code. The check 2599 * in tcf_fill_node prevents it. However, compiler does not 2600 * see that far, so set parent to zero to silence the warning 2601 * about parent being uninitialized. 2602 */ 2603 parent = 0; 2604 } else { 2605 const struct Qdisc_class_ops *cops; 2606 struct net_device *dev; 2607 unsigned long cl = 0; 2608 2609 dev = __dev_get_by_index(net, tcm->tcm_ifindex); 2610 if (!dev) 2611 return skb->len; 2612 2613 parent = tcm->tcm_parent; 2614 if (!parent) { 2615 q = dev->qdisc; 2616 parent = q->handle; 2617 } else { 2618 q = qdisc_lookup(dev, TC_H_MAJ(tcm->tcm_parent)); 2619 } 2620 if (!q) 2621 goto out; 2622 cops = q->ops->cl_ops; 2623 if (!cops) 2624 goto out; 2625 if (!cops->tcf_block) 2626 goto out; 2627 if (TC_H_MIN(tcm->tcm_parent)) { 2628 cl = cops->find(q, tcm->tcm_parent); 2629 if (cl == 0) 2630 goto out; 2631 } 2632 block = cops->tcf_block(q, cl, NULL); 2633 if (!block) 2634 goto out; 2635 if (tcf_block_shared(block)) 2636 q = NULL; 2637 } 2638 2639 index_start = cb->args[0]; 2640 index = 0; 2641 2642 for (chain = __tcf_get_next_chain(block, NULL); 2643 chain; 2644 chain_prev = chain, 2645 chain = __tcf_get_next_chain(block, chain), 2646 tcf_chain_put(chain_prev)) { 2647 if (tca[TCA_CHAIN] && 2648 nla_get_u32(tca[TCA_CHAIN]) != chain->index) 2649 continue; 2650 if (!tcf_chain_dump(chain, q, parent, skb, cb, 2651 index_start, &index)) { 2652 tcf_chain_put(chain); 2653 err = -EMSGSIZE; 2654 break; 2655 } 2656 } 2657 2658 if (tcm->tcm_ifindex == TCM_IFINDEX_MAGIC_BLOCK) 2659 tcf_block_refcnt_put(block, true); 2660 cb->args[0] = index; 2661 2662 out: 2663 /* If we did no progress, the error (EMSGSIZE) is real */ 2664 if (skb->len == 0 && err) 2665 return err; 2666 return skb->len; 2667 } 2668 2669 static int tc_chain_fill_node(const struct tcf_proto_ops *tmplt_ops, 2670 void *tmplt_priv, u32 chain_index, 2671 struct net *net, struct sk_buff *skb, 2672 struct tcf_block *block, 2673 u32 portid, u32 seq, u16 flags, int event) 2674 { 2675 unsigned char *b = skb_tail_pointer(skb); 2676 const struct tcf_proto_ops *ops; 2677 struct nlmsghdr *nlh; 2678 struct tcmsg *tcm; 2679 void *priv; 2680 2681 ops = tmplt_ops; 2682 priv = tmplt_priv; 2683 2684 nlh = nlmsg_put(skb, portid, seq, event, sizeof(*tcm), flags); 2685 if (!nlh) 2686 goto out_nlmsg_trim; 2687 tcm = nlmsg_data(nlh); 2688 tcm->tcm_family = AF_UNSPEC; 2689 tcm->tcm__pad1 = 0; 2690 tcm->tcm__pad2 = 0; 2691 tcm->tcm_handle = 0; 2692 if (block->q) { 2693 tcm->tcm_ifindex = qdisc_dev(block->q)->ifindex; 2694 tcm->tcm_parent = block->q->handle; 2695 } else { 2696 tcm->tcm_ifindex = TCM_IFINDEX_MAGIC_BLOCK; 2697 tcm->tcm_block_index = block->index; 2698 } 2699 2700 if (nla_put_u32(skb, TCA_CHAIN, chain_index)) 2701 goto nla_put_failure; 2702 2703 if (ops) { 2704 if (nla_put_string(skb, TCA_KIND, ops->kind)) 2705 goto nla_put_failure; 2706 if (ops->tmplt_dump(skb, net, priv) < 0) 2707 goto nla_put_failure; 2708 } 2709 2710 nlh->nlmsg_len = skb_tail_pointer(skb) - b; 2711 return skb->len; 2712 2713 out_nlmsg_trim: 2714 nla_put_failure: 2715 nlmsg_trim(skb, b); 2716 return -EMSGSIZE; 2717 } 2718 2719 static int tc_chain_notify(struct tcf_chain *chain, struct sk_buff *oskb, 2720 u32 seq, u16 flags, int event, bool unicast) 2721 { 2722 u32 portid = oskb ? NETLINK_CB(oskb).portid : 0; 2723 struct tcf_block *block = chain->block; 2724 struct net *net = block->net; 2725 struct sk_buff *skb; 2726 int err = 0; 2727 2728 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL); 2729 if (!skb) 2730 return -ENOBUFS; 2731 2732 if (tc_chain_fill_node(chain->tmplt_ops, chain->tmplt_priv, 2733 chain->index, net, skb, block, portid, 2734 seq, flags, event) <= 0) { 2735 kfree_skb(skb); 2736 return -EINVAL; 2737 } 2738 2739 if (unicast) 2740 err = netlink_unicast(net->rtnl, skb, portid, MSG_DONTWAIT); 2741 else 2742 err = rtnetlink_send(skb, net, portid, RTNLGRP_TC, 2743 flags & NLM_F_ECHO); 2744 2745 if (err > 0) 2746 err = 0; 2747 return err; 2748 } 2749 2750 static int tc_chain_notify_delete(const struct tcf_proto_ops *tmplt_ops, 2751 void *tmplt_priv, u32 chain_index, 2752 struct tcf_block *block, struct sk_buff *oskb, 2753 u32 seq, u16 flags, bool unicast) 2754 { 2755 u32 portid = oskb ? NETLINK_CB(oskb).portid : 0; 2756 struct net *net = block->net; 2757 struct sk_buff *skb; 2758 2759 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL); 2760 if (!skb) 2761 return -ENOBUFS; 2762 2763 if (tc_chain_fill_node(tmplt_ops, tmplt_priv, chain_index, net, skb, 2764 block, portid, seq, flags, RTM_DELCHAIN) <= 0) { 2765 kfree_skb(skb); 2766 return -EINVAL; 2767 } 2768 2769 if (unicast) 2770 return netlink_unicast(net->rtnl, skb, portid, MSG_DONTWAIT); 2771 2772 return rtnetlink_send(skb, net, portid, RTNLGRP_TC, flags & NLM_F_ECHO); 2773 } 2774 2775 static int tc_chain_tmplt_add(struct tcf_chain *chain, struct net *net, 2776 struct nlattr **tca, 2777 struct netlink_ext_ack *extack) 2778 { 2779 const struct tcf_proto_ops *ops; 2780 char name[IFNAMSIZ]; 2781 void *tmplt_priv; 2782 2783 /* If kind is not set, user did not specify template. */ 2784 if (!tca[TCA_KIND]) 2785 return 0; 2786 2787 if (tcf_proto_check_kind(tca[TCA_KIND], name)) { 2788 NL_SET_ERR_MSG(extack, "Specified TC chain template name too long"); 2789 return -EINVAL; 2790 } 2791 2792 ops = tcf_proto_lookup_ops(name, true, extack); 2793 if (IS_ERR(ops)) 2794 return PTR_ERR(ops); 2795 if (!ops->tmplt_create || !ops->tmplt_destroy || !ops->tmplt_dump) { 2796 NL_SET_ERR_MSG(extack, "Chain templates are not supported with specified classifier"); 2797 return -EOPNOTSUPP; 2798 } 2799 2800 tmplt_priv = ops->tmplt_create(net, chain, tca, extack); 2801 if (IS_ERR(tmplt_priv)) { 2802 module_put(ops->owner); 2803 return PTR_ERR(tmplt_priv); 2804 } 2805 chain->tmplt_ops = ops; 2806 chain->tmplt_priv = tmplt_priv; 2807 return 0; 2808 } 2809 2810 static void tc_chain_tmplt_del(const struct tcf_proto_ops *tmplt_ops, 2811 void *tmplt_priv) 2812 { 2813 /* If template ops are set, no work to do for us. */ 2814 if (!tmplt_ops) 2815 return; 2816 2817 tmplt_ops->tmplt_destroy(tmplt_priv); 2818 module_put(tmplt_ops->owner); 2819 } 2820 2821 /* Add/delete/get a chain */ 2822 2823 static int tc_ctl_chain(struct sk_buff *skb, struct nlmsghdr *n, 2824 struct netlink_ext_ack *extack) 2825 { 2826 struct net *net = sock_net(skb->sk); 2827 struct nlattr *tca[TCA_MAX + 1]; 2828 struct tcmsg *t; 2829 u32 parent; 2830 u32 chain_index; 2831 struct Qdisc *q = NULL; 2832 struct tcf_chain *chain = NULL; 2833 struct tcf_block *block; 2834 unsigned long cl; 2835 int err; 2836 2837 if (n->nlmsg_type != RTM_GETCHAIN && 2838 !netlink_ns_capable(skb, net->user_ns, CAP_NET_ADMIN)) 2839 return -EPERM; 2840 2841 replay: 2842 err = nlmsg_parse_deprecated(n, sizeof(*t), tca, TCA_MAX, 2843 rtm_tca_policy, extack); 2844 if (err < 0) 2845 return err; 2846 2847 t = nlmsg_data(n); 2848 parent = t->tcm_parent; 2849 cl = 0; 2850 2851 block = tcf_block_find(net, &q, &parent, &cl, 2852 t->tcm_ifindex, t->tcm_block_index, extack); 2853 if (IS_ERR(block)) 2854 return PTR_ERR(block); 2855 2856 chain_index = tca[TCA_CHAIN] ? nla_get_u32(tca[TCA_CHAIN]) : 0; 2857 if (chain_index > TC_ACT_EXT_VAL_MASK) { 2858 NL_SET_ERR_MSG(extack, "Specified chain index exceeds upper limit"); 2859 err = -EINVAL; 2860 goto errout_block; 2861 } 2862 2863 mutex_lock(&block->lock); 2864 chain = tcf_chain_lookup(block, chain_index); 2865 if (n->nlmsg_type == RTM_NEWCHAIN) { 2866 if (chain) { 2867 if (tcf_chain_held_by_acts_only(chain)) { 2868 /* The chain exists only because there is 2869 * some action referencing it. 2870 */ 2871 tcf_chain_hold(chain); 2872 } else { 2873 NL_SET_ERR_MSG(extack, "Filter chain already exists"); 2874 err = -EEXIST; 2875 goto errout_block_locked; 2876 } 2877 } else { 2878 if (!(n->nlmsg_flags & NLM_F_CREATE)) { 2879 NL_SET_ERR_MSG(extack, "Need both RTM_NEWCHAIN and NLM_F_CREATE to create a new chain"); 2880 err = -ENOENT; 2881 goto errout_block_locked; 2882 } 2883 chain = tcf_chain_create(block, chain_index); 2884 if (!chain) { 2885 NL_SET_ERR_MSG(extack, "Failed to create filter chain"); 2886 err = -ENOMEM; 2887 goto errout_block_locked; 2888 } 2889 } 2890 } else { 2891 if (!chain || tcf_chain_held_by_acts_only(chain)) { 2892 NL_SET_ERR_MSG(extack, "Cannot find specified filter chain"); 2893 err = -EINVAL; 2894 goto errout_block_locked; 2895 } 2896 tcf_chain_hold(chain); 2897 } 2898 2899 if (n->nlmsg_type == RTM_NEWCHAIN) { 2900 /* Modifying chain requires holding parent block lock. In case 2901 * the chain was successfully added, take a reference to the 2902 * chain. This ensures that an empty chain does not disappear at 2903 * the end of this function. 2904 */ 2905 tcf_chain_hold(chain); 2906 chain->explicitly_created = true; 2907 } 2908 mutex_unlock(&block->lock); 2909 2910 switch (n->nlmsg_type) { 2911 case RTM_NEWCHAIN: 2912 err = tc_chain_tmplt_add(chain, net, tca, extack); 2913 if (err) { 2914 tcf_chain_put_explicitly_created(chain); 2915 goto errout; 2916 } 2917 2918 tc_chain_notify(chain, NULL, 0, NLM_F_CREATE | NLM_F_EXCL, 2919 RTM_NEWCHAIN, false); 2920 break; 2921 case RTM_DELCHAIN: 2922 tfilter_notify_chain(net, skb, block, q, parent, n, 2923 chain, RTM_DELTFILTER, true); 2924 /* Flush the chain first as the user requested chain removal. */ 2925 tcf_chain_flush(chain, true); 2926 /* In case the chain was successfully deleted, put a reference 2927 * to the chain previously taken during addition. 2928 */ 2929 tcf_chain_put_explicitly_created(chain); 2930 break; 2931 case RTM_GETCHAIN: 2932 err = tc_chain_notify(chain, skb, n->nlmsg_seq, 2933 n->nlmsg_seq, n->nlmsg_type, true); 2934 if (err < 0) 2935 NL_SET_ERR_MSG(extack, "Failed to send chain notify message"); 2936 break; 2937 default: 2938 err = -EOPNOTSUPP; 2939 NL_SET_ERR_MSG(extack, "Unsupported message type"); 2940 goto errout; 2941 } 2942 2943 errout: 2944 tcf_chain_put(chain); 2945 errout_block: 2946 tcf_block_release(q, block, true); 2947 if (err == -EAGAIN) 2948 /* Replay the request. */ 2949 goto replay; 2950 return err; 2951 2952 errout_block_locked: 2953 mutex_unlock(&block->lock); 2954 goto errout_block; 2955 } 2956 2957 /* called with RTNL */ 2958 static int tc_dump_chain(struct sk_buff *skb, struct netlink_callback *cb) 2959 { 2960 struct net *net = sock_net(skb->sk); 2961 struct nlattr *tca[TCA_MAX + 1]; 2962 struct Qdisc *q = NULL; 2963 struct tcf_block *block; 2964 struct tcmsg *tcm = nlmsg_data(cb->nlh); 2965 struct tcf_chain *chain; 2966 long index_start; 2967 long index; 2968 u32 parent; 2969 int err; 2970 2971 if (nlmsg_len(cb->nlh) < sizeof(*tcm)) 2972 return skb->len; 2973 2974 err = nlmsg_parse_deprecated(cb->nlh, sizeof(*tcm), tca, TCA_MAX, 2975 rtm_tca_policy, cb->extack); 2976 if (err) 2977 return err; 2978 2979 if (tcm->tcm_ifindex == TCM_IFINDEX_MAGIC_BLOCK) { 2980 block = tcf_block_refcnt_get(net, tcm->tcm_block_index); 2981 if (!block) 2982 goto out; 2983 /* If we work with block index, q is NULL and parent value 2984 * will never be used in the following code. The check 2985 * in tcf_fill_node prevents it. However, compiler does not 2986 * see that far, so set parent to zero to silence the warning 2987 * about parent being uninitialized. 2988 */ 2989 parent = 0; 2990 } else { 2991 const struct Qdisc_class_ops *cops; 2992 struct net_device *dev; 2993 unsigned long cl = 0; 2994 2995 dev = __dev_get_by_index(net, tcm->tcm_ifindex); 2996 if (!dev) 2997 return skb->len; 2998 2999 parent = tcm->tcm_parent; 3000 if (!parent) { 3001 q = dev->qdisc; 3002 parent = q->handle; 3003 } else { 3004 q = qdisc_lookup(dev, TC_H_MAJ(tcm->tcm_parent)); 3005 } 3006 if (!q) 3007 goto out; 3008 cops = q->ops->cl_ops; 3009 if (!cops) 3010 goto out; 3011 if (!cops->tcf_block) 3012 goto out; 3013 if (TC_H_MIN(tcm->tcm_parent)) { 3014 cl = cops->find(q, tcm->tcm_parent); 3015 if (cl == 0) 3016 goto out; 3017 } 3018 block = cops->tcf_block(q, cl, NULL); 3019 if (!block) 3020 goto out; 3021 if (tcf_block_shared(block)) 3022 q = NULL; 3023 } 3024 3025 index_start = cb->args[0]; 3026 index = 0; 3027 3028 mutex_lock(&block->lock); 3029 list_for_each_entry(chain, &block->chain_list, list) { 3030 if ((tca[TCA_CHAIN] && 3031 nla_get_u32(tca[TCA_CHAIN]) != chain->index)) 3032 continue; 3033 if (index < index_start) { 3034 index++; 3035 continue; 3036 } 3037 if (tcf_chain_held_by_acts_only(chain)) 3038 continue; 3039 err = tc_chain_fill_node(chain->tmplt_ops, chain->tmplt_priv, 3040 chain->index, net, skb, block, 3041 NETLINK_CB(cb->skb).portid, 3042 cb->nlh->nlmsg_seq, NLM_F_MULTI, 3043 RTM_NEWCHAIN); 3044 if (err <= 0) 3045 break; 3046 index++; 3047 } 3048 mutex_unlock(&block->lock); 3049 3050 if (tcm->tcm_ifindex == TCM_IFINDEX_MAGIC_BLOCK) 3051 tcf_block_refcnt_put(block, true); 3052 cb->args[0] = index; 3053 3054 out: 3055 /* If we did no progress, the error (EMSGSIZE) is real */ 3056 if (skb->len == 0 && err) 3057 return err; 3058 return skb->len; 3059 } 3060 3061 void tcf_exts_destroy(struct tcf_exts *exts) 3062 { 3063 #ifdef CONFIG_NET_CLS_ACT 3064 if (exts->actions) { 3065 tcf_action_destroy(exts->actions, TCA_ACT_UNBIND); 3066 kfree(exts->actions); 3067 } 3068 exts->nr_actions = 0; 3069 #endif 3070 } 3071 EXPORT_SYMBOL(tcf_exts_destroy); 3072 3073 int tcf_exts_validate(struct net *net, struct tcf_proto *tp, struct nlattr **tb, 3074 struct nlattr *rate_tlv, struct tcf_exts *exts, bool ovr, 3075 bool rtnl_held, struct netlink_ext_ack *extack) 3076 { 3077 #ifdef CONFIG_NET_CLS_ACT 3078 { 3079 struct tc_action *act; 3080 size_t attr_size = 0; 3081 3082 if (exts->police && tb[exts->police]) { 3083 act = tcf_action_init_1(net, tp, tb[exts->police], 3084 rate_tlv, "police", ovr, 3085 TCA_ACT_BIND, rtnl_held, 3086 extack); 3087 if (IS_ERR(act)) 3088 return PTR_ERR(act); 3089 3090 act->type = exts->type = TCA_OLD_COMPAT; 3091 exts->actions[0] = act; 3092 exts->nr_actions = 1; 3093 } else if (exts->action && tb[exts->action]) { 3094 int err; 3095 3096 err = tcf_action_init(net, tp, tb[exts->action], 3097 rate_tlv, NULL, ovr, TCA_ACT_BIND, 3098 exts->actions, &attr_size, 3099 rtnl_held, extack); 3100 if (err < 0) 3101 return err; 3102 exts->nr_actions = err; 3103 } 3104 } 3105 #else 3106 if ((exts->action && tb[exts->action]) || 3107 (exts->police && tb[exts->police])) { 3108 NL_SET_ERR_MSG(extack, "Classifier actions are not supported per compile options (CONFIG_NET_CLS_ACT)"); 3109 return -EOPNOTSUPP; 3110 } 3111 #endif 3112 3113 return 0; 3114 } 3115 EXPORT_SYMBOL(tcf_exts_validate); 3116 3117 void tcf_exts_change(struct tcf_exts *dst, struct tcf_exts *src) 3118 { 3119 #ifdef CONFIG_NET_CLS_ACT 3120 struct tcf_exts old = *dst; 3121 3122 *dst = *src; 3123 tcf_exts_destroy(&old); 3124 #endif 3125 } 3126 EXPORT_SYMBOL(tcf_exts_change); 3127 3128 #ifdef CONFIG_NET_CLS_ACT 3129 static struct tc_action *tcf_exts_first_act(struct tcf_exts *exts) 3130 { 3131 if (exts->nr_actions == 0) 3132 return NULL; 3133 else 3134 return exts->actions[0]; 3135 } 3136 #endif 3137 3138 int tcf_exts_dump(struct sk_buff *skb, struct tcf_exts *exts) 3139 { 3140 #ifdef CONFIG_NET_CLS_ACT 3141 struct nlattr *nest; 3142 3143 if (exts->action && tcf_exts_has_actions(exts)) { 3144 /* 3145 * again for backward compatible mode - we want 3146 * to work with both old and new modes of entering 3147 * tc data even if iproute2 was newer - jhs 3148 */ 3149 if (exts->type != TCA_OLD_COMPAT) { 3150 nest = nla_nest_start_noflag(skb, exts->action); 3151 if (nest == NULL) 3152 goto nla_put_failure; 3153 3154 if (tcf_action_dump(skb, exts->actions, 0, 0) < 0) 3155 goto nla_put_failure; 3156 nla_nest_end(skb, nest); 3157 } else if (exts->police) { 3158 struct tc_action *act = tcf_exts_first_act(exts); 3159 nest = nla_nest_start_noflag(skb, exts->police); 3160 if (nest == NULL || !act) 3161 goto nla_put_failure; 3162 if (tcf_action_dump_old(skb, act, 0, 0) < 0) 3163 goto nla_put_failure; 3164 nla_nest_end(skb, nest); 3165 } 3166 } 3167 return 0; 3168 3169 nla_put_failure: 3170 nla_nest_cancel(skb, nest); 3171 return -1; 3172 #else 3173 return 0; 3174 #endif 3175 } 3176 EXPORT_SYMBOL(tcf_exts_dump); 3177 3178 3179 int tcf_exts_dump_stats(struct sk_buff *skb, struct tcf_exts *exts) 3180 { 3181 #ifdef CONFIG_NET_CLS_ACT 3182 struct tc_action *a = tcf_exts_first_act(exts); 3183 if (a != NULL && tcf_action_copy_stats(skb, a, 1) < 0) 3184 return -1; 3185 #endif 3186 return 0; 3187 } 3188 EXPORT_SYMBOL(tcf_exts_dump_stats); 3189 3190 static void tcf_block_offload_inc(struct tcf_block *block, u32 *flags) 3191 { 3192 if (*flags & TCA_CLS_FLAGS_IN_HW) 3193 return; 3194 *flags |= TCA_CLS_FLAGS_IN_HW; 3195 atomic_inc(&block->offloadcnt); 3196 } 3197 3198 static void tcf_block_offload_dec(struct tcf_block *block, u32 *flags) 3199 { 3200 if (!(*flags & TCA_CLS_FLAGS_IN_HW)) 3201 return; 3202 *flags &= ~TCA_CLS_FLAGS_IN_HW; 3203 atomic_dec(&block->offloadcnt); 3204 } 3205 3206 static void tc_cls_offload_cnt_update(struct tcf_block *block, 3207 struct tcf_proto *tp, u32 *cnt, 3208 u32 *flags, u32 diff, bool add) 3209 { 3210 lockdep_assert_held(&block->cb_lock); 3211 3212 spin_lock(&tp->lock); 3213 if (add) { 3214 if (!*cnt) 3215 tcf_block_offload_inc(block, flags); 3216 *cnt += diff; 3217 } else { 3218 *cnt -= diff; 3219 if (!*cnt) 3220 tcf_block_offload_dec(block, flags); 3221 } 3222 spin_unlock(&tp->lock); 3223 } 3224 3225 static void 3226 tc_cls_offload_cnt_reset(struct tcf_block *block, struct tcf_proto *tp, 3227 u32 *cnt, u32 *flags) 3228 { 3229 lockdep_assert_held(&block->cb_lock); 3230 3231 spin_lock(&tp->lock); 3232 tcf_block_offload_dec(block, flags); 3233 *cnt = 0; 3234 spin_unlock(&tp->lock); 3235 } 3236 3237 static int 3238 __tc_setup_cb_call(struct tcf_block *block, enum tc_setup_type type, 3239 void *type_data, bool err_stop) 3240 { 3241 struct flow_block_cb *block_cb; 3242 int ok_count = 0; 3243 int err; 3244 3245 list_for_each_entry(block_cb, &block->flow_block.cb_list, list) { 3246 err = block_cb->cb(type, type_data, block_cb->cb_priv); 3247 if (err) { 3248 if (err_stop) 3249 return err; 3250 } else { 3251 ok_count++; 3252 } 3253 } 3254 return ok_count; 3255 } 3256 3257 int tc_setup_cb_call(struct tcf_block *block, enum tc_setup_type type, 3258 void *type_data, bool err_stop, bool rtnl_held) 3259 { 3260 bool take_rtnl = READ_ONCE(block->lockeddevcnt) && !rtnl_held; 3261 int ok_count; 3262 3263 retry: 3264 if (take_rtnl) 3265 rtnl_lock(); 3266 down_read(&block->cb_lock); 3267 /* Need to obtain rtnl lock if block is bound to devs that require it. 3268 * In block bind code cb_lock is obtained while holding rtnl, so we must 3269 * obtain the locks in same order here. 3270 */ 3271 if (!rtnl_held && !take_rtnl && block->lockeddevcnt) { 3272 up_read(&block->cb_lock); 3273 take_rtnl = true; 3274 goto retry; 3275 } 3276 3277 ok_count = __tc_setup_cb_call(block, type, type_data, err_stop); 3278 3279 up_read(&block->cb_lock); 3280 if (take_rtnl) 3281 rtnl_unlock(); 3282 return ok_count; 3283 } 3284 EXPORT_SYMBOL(tc_setup_cb_call); 3285 3286 /* Non-destructive filter add. If filter that wasn't already in hardware is 3287 * successfully offloaded, increment block offloads counter. On failure, 3288 * previously offloaded filter is considered to be intact and offloads counter 3289 * is not decremented. 3290 */ 3291 3292 int tc_setup_cb_add(struct tcf_block *block, struct tcf_proto *tp, 3293 enum tc_setup_type type, void *type_data, bool err_stop, 3294 u32 *flags, unsigned int *in_hw_count, bool rtnl_held) 3295 { 3296 bool take_rtnl = READ_ONCE(block->lockeddevcnt) && !rtnl_held; 3297 int ok_count; 3298 3299 retry: 3300 if (take_rtnl) 3301 rtnl_lock(); 3302 down_read(&block->cb_lock); 3303 /* Need to obtain rtnl lock if block is bound to devs that require it. 3304 * In block bind code cb_lock is obtained while holding rtnl, so we must 3305 * obtain the locks in same order here. 3306 */ 3307 if (!rtnl_held && !take_rtnl && block->lockeddevcnt) { 3308 up_read(&block->cb_lock); 3309 take_rtnl = true; 3310 goto retry; 3311 } 3312 3313 /* Make sure all netdevs sharing this block are offload-capable. */ 3314 if (block->nooffloaddevcnt && err_stop) { 3315 ok_count = -EOPNOTSUPP; 3316 goto err_unlock; 3317 } 3318 3319 ok_count = __tc_setup_cb_call(block, type, type_data, err_stop); 3320 if (ok_count < 0) 3321 goto err_unlock; 3322 3323 if (tp->ops->hw_add) 3324 tp->ops->hw_add(tp, type_data); 3325 if (ok_count > 0) 3326 tc_cls_offload_cnt_update(block, tp, in_hw_count, flags, 3327 ok_count, true); 3328 err_unlock: 3329 up_read(&block->cb_lock); 3330 if (take_rtnl) 3331 rtnl_unlock(); 3332 return ok_count < 0 ? ok_count : 0; 3333 } 3334 EXPORT_SYMBOL(tc_setup_cb_add); 3335 3336 /* Destructive filter replace. If filter that wasn't already in hardware is 3337 * successfully offloaded, increment block offload counter. On failure, 3338 * previously offloaded filter is considered to be destroyed and offload counter 3339 * is decremented. 3340 */ 3341 3342 int tc_setup_cb_replace(struct tcf_block *block, struct tcf_proto *tp, 3343 enum tc_setup_type type, void *type_data, bool err_stop, 3344 u32 *old_flags, unsigned int *old_in_hw_count, 3345 u32 *new_flags, unsigned int *new_in_hw_count, 3346 bool rtnl_held) 3347 { 3348 bool take_rtnl = READ_ONCE(block->lockeddevcnt) && !rtnl_held; 3349 int ok_count; 3350 3351 retry: 3352 if (take_rtnl) 3353 rtnl_lock(); 3354 down_read(&block->cb_lock); 3355 /* Need to obtain rtnl lock if block is bound to devs that require it. 3356 * In block bind code cb_lock is obtained while holding rtnl, so we must 3357 * obtain the locks in same order here. 3358 */ 3359 if (!rtnl_held && !take_rtnl && block->lockeddevcnt) { 3360 up_read(&block->cb_lock); 3361 take_rtnl = true; 3362 goto retry; 3363 } 3364 3365 /* Make sure all netdevs sharing this block are offload-capable. */ 3366 if (block->nooffloaddevcnt && err_stop) { 3367 ok_count = -EOPNOTSUPP; 3368 goto err_unlock; 3369 } 3370 3371 tc_cls_offload_cnt_reset(block, tp, old_in_hw_count, old_flags); 3372 if (tp->ops->hw_del) 3373 tp->ops->hw_del(tp, type_data); 3374 3375 ok_count = __tc_setup_cb_call(block, type, type_data, err_stop); 3376 if (ok_count < 0) 3377 goto err_unlock; 3378 3379 if (tp->ops->hw_add) 3380 tp->ops->hw_add(tp, type_data); 3381 if (ok_count > 0) 3382 tc_cls_offload_cnt_update(block, tp, new_in_hw_count, 3383 new_flags, ok_count, true); 3384 err_unlock: 3385 up_read(&block->cb_lock); 3386 if (take_rtnl) 3387 rtnl_unlock(); 3388 return ok_count < 0 ? ok_count : 0; 3389 } 3390 EXPORT_SYMBOL(tc_setup_cb_replace); 3391 3392 /* Destroy filter and decrement block offload counter, if filter was previously 3393 * offloaded. 3394 */ 3395 3396 int tc_setup_cb_destroy(struct tcf_block *block, struct tcf_proto *tp, 3397 enum tc_setup_type type, void *type_data, bool err_stop, 3398 u32 *flags, unsigned int *in_hw_count, bool rtnl_held) 3399 { 3400 bool take_rtnl = READ_ONCE(block->lockeddevcnt) && !rtnl_held; 3401 int ok_count; 3402 3403 retry: 3404 if (take_rtnl) 3405 rtnl_lock(); 3406 down_read(&block->cb_lock); 3407 /* Need to obtain rtnl lock if block is bound to devs that require it. 3408 * In block bind code cb_lock is obtained while holding rtnl, so we must 3409 * obtain the locks in same order here. 3410 */ 3411 if (!rtnl_held && !take_rtnl && block->lockeddevcnt) { 3412 up_read(&block->cb_lock); 3413 take_rtnl = true; 3414 goto retry; 3415 } 3416 3417 ok_count = __tc_setup_cb_call(block, type, type_data, err_stop); 3418 3419 tc_cls_offload_cnt_reset(block, tp, in_hw_count, flags); 3420 if (tp->ops->hw_del) 3421 tp->ops->hw_del(tp, type_data); 3422 3423 up_read(&block->cb_lock); 3424 if (take_rtnl) 3425 rtnl_unlock(); 3426 return ok_count < 0 ? ok_count : 0; 3427 } 3428 EXPORT_SYMBOL(tc_setup_cb_destroy); 3429 3430 int tc_setup_cb_reoffload(struct tcf_block *block, struct tcf_proto *tp, 3431 bool add, flow_setup_cb_t *cb, 3432 enum tc_setup_type type, void *type_data, 3433 void *cb_priv, u32 *flags, unsigned int *in_hw_count) 3434 { 3435 int err = cb(type, type_data, cb_priv); 3436 3437 if (err) { 3438 if (add && tc_skip_sw(*flags)) 3439 return err; 3440 } else { 3441 tc_cls_offload_cnt_update(block, tp, in_hw_count, flags, 1, 3442 add); 3443 } 3444 3445 return 0; 3446 } 3447 EXPORT_SYMBOL(tc_setup_cb_reoffload); 3448 3449 static int tcf_act_get_cookie(struct flow_action_entry *entry, 3450 const struct tc_action *act) 3451 { 3452 struct tc_cookie *cookie; 3453 int err = 0; 3454 3455 rcu_read_lock(); 3456 cookie = rcu_dereference(act->act_cookie); 3457 if (cookie) { 3458 entry->cookie = flow_action_cookie_create(cookie->data, 3459 cookie->len, 3460 GFP_ATOMIC); 3461 if (!entry->cookie) 3462 err = -ENOMEM; 3463 } 3464 rcu_read_unlock(); 3465 return err; 3466 } 3467 3468 static void tcf_act_put_cookie(struct flow_action_entry *entry) 3469 { 3470 flow_action_cookie_destroy(entry->cookie); 3471 } 3472 3473 void tc_cleanup_flow_action(struct flow_action *flow_action) 3474 { 3475 struct flow_action_entry *entry; 3476 int i; 3477 3478 flow_action_for_each(i, entry, flow_action) { 3479 tcf_act_put_cookie(entry); 3480 if (entry->destructor) 3481 entry->destructor(entry->destructor_priv); 3482 } 3483 } 3484 EXPORT_SYMBOL(tc_cleanup_flow_action); 3485 3486 static void tcf_mirred_get_dev(struct flow_action_entry *entry, 3487 const struct tc_action *act) 3488 { 3489 #ifdef CONFIG_NET_CLS_ACT 3490 entry->dev = act->ops->get_dev(act, &entry->destructor); 3491 if (!entry->dev) 3492 return; 3493 entry->destructor_priv = entry->dev; 3494 #endif 3495 } 3496 3497 static void tcf_tunnel_encap_put_tunnel(void *priv) 3498 { 3499 struct ip_tunnel_info *tunnel = priv; 3500 3501 kfree(tunnel); 3502 } 3503 3504 static int tcf_tunnel_encap_get_tunnel(struct flow_action_entry *entry, 3505 const struct tc_action *act) 3506 { 3507 entry->tunnel = tcf_tunnel_info_copy(act); 3508 if (!entry->tunnel) 3509 return -ENOMEM; 3510 entry->destructor = tcf_tunnel_encap_put_tunnel; 3511 entry->destructor_priv = entry->tunnel; 3512 return 0; 3513 } 3514 3515 static void tcf_sample_get_group(struct flow_action_entry *entry, 3516 const struct tc_action *act) 3517 { 3518 #ifdef CONFIG_NET_CLS_ACT 3519 entry->sample.psample_group = 3520 act->ops->get_psample_group(act, &entry->destructor); 3521 entry->destructor_priv = entry->sample.psample_group; 3522 #endif 3523 } 3524 3525 int tc_setup_flow_action(struct flow_action *flow_action, 3526 const struct tcf_exts *exts) 3527 { 3528 struct tc_action *act; 3529 int i, j, k, err = 0; 3530 3531 BUILD_BUG_ON(TCA_ACT_HW_STATS_ANY != FLOW_ACTION_HW_STATS_ANY); 3532 BUILD_BUG_ON(TCA_ACT_HW_STATS_IMMEDIATE != FLOW_ACTION_HW_STATS_IMMEDIATE); 3533 BUILD_BUG_ON(TCA_ACT_HW_STATS_DELAYED != FLOW_ACTION_HW_STATS_DELAYED); 3534 3535 if (!exts) 3536 return 0; 3537 3538 j = 0; 3539 tcf_exts_for_each_action(i, act, exts) { 3540 struct flow_action_entry *entry; 3541 3542 entry = &flow_action->entries[j]; 3543 spin_lock_bh(&act->tcfa_lock); 3544 err = tcf_act_get_cookie(entry, act); 3545 if (err) 3546 goto err_out_locked; 3547 3548 entry->hw_stats = act->hw_stats; 3549 3550 if (is_tcf_gact_ok(act)) { 3551 entry->id = FLOW_ACTION_ACCEPT; 3552 } else if (is_tcf_gact_shot(act)) { 3553 entry->id = FLOW_ACTION_DROP; 3554 } else if (is_tcf_gact_trap(act)) { 3555 entry->id = FLOW_ACTION_TRAP; 3556 } else if (is_tcf_gact_goto_chain(act)) { 3557 entry->id = FLOW_ACTION_GOTO; 3558 entry->chain_index = tcf_gact_goto_chain_index(act); 3559 } else if (is_tcf_mirred_egress_redirect(act)) { 3560 entry->id = FLOW_ACTION_REDIRECT; 3561 tcf_mirred_get_dev(entry, act); 3562 } else if (is_tcf_mirred_egress_mirror(act)) { 3563 entry->id = FLOW_ACTION_MIRRED; 3564 tcf_mirred_get_dev(entry, act); 3565 } else if (is_tcf_mirred_ingress_redirect(act)) { 3566 entry->id = FLOW_ACTION_REDIRECT_INGRESS; 3567 tcf_mirred_get_dev(entry, act); 3568 } else if (is_tcf_mirred_ingress_mirror(act)) { 3569 entry->id = FLOW_ACTION_MIRRED_INGRESS; 3570 tcf_mirred_get_dev(entry, act); 3571 } else if (is_tcf_vlan(act)) { 3572 switch (tcf_vlan_action(act)) { 3573 case TCA_VLAN_ACT_PUSH: 3574 entry->id = FLOW_ACTION_VLAN_PUSH; 3575 entry->vlan.vid = tcf_vlan_push_vid(act); 3576 entry->vlan.proto = tcf_vlan_push_proto(act); 3577 entry->vlan.prio = tcf_vlan_push_prio(act); 3578 break; 3579 case TCA_VLAN_ACT_POP: 3580 entry->id = FLOW_ACTION_VLAN_POP; 3581 break; 3582 case TCA_VLAN_ACT_MODIFY: 3583 entry->id = FLOW_ACTION_VLAN_MANGLE; 3584 entry->vlan.vid = tcf_vlan_push_vid(act); 3585 entry->vlan.proto = tcf_vlan_push_proto(act); 3586 entry->vlan.prio = tcf_vlan_push_prio(act); 3587 break; 3588 default: 3589 err = -EOPNOTSUPP; 3590 goto err_out_locked; 3591 } 3592 } else if (is_tcf_tunnel_set(act)) { 3593 entry->id = FLOW_ACTION_TUNNEL_ENCAP; 3594 err = tcf_tunnel_encap_get_tunnel(entry, act); 3595 if (err) 3596 goto err_out_locked; 3597 } else if (is_tcf_tunnel_release(act)) { 3598 entry->id = FLOW_ACTION_TUNNEL_DECAP; 3599 } else if (is_tcf_pedit(act)) { 3600 for (k = 0; k < tcf_pedit_nkeys(act); k++) { 3601 switch (tcf_pedit_cmd(act, k)) { 3602 case TCA_PEDIT_KEY_EX_CMD_SET: 3603 entry->id = FLOW_ACTION_MANGLE; 3604 break; 3605 case TCA_PEDIT_KEY_EX_CMD_ADD: 3606 entry->id = FLOW_ACTION_ADD; 3607 break; 3608 default: 3609 err = -EOPNOTSUPP; 3610 goto err_out_locked; 3611 } 3612 entry->mangle.htype = tcf_pedit_htype(act, k); 3613 entry->mangle.mask = tcf_pedit_mask(act, k); 3614 entry->mangle.val = tcf_pedit_val(act, k); 3615 entry->mangle.offset = tcf_pedit_offset(act, k); 3616 entry->hw_stats = act->hw_stats; 3617 entry = &flow_action->entries[++j]; 3618 } 3619 } else if (is_tcf_csum(act)) { 3620 entry->id = FLOW_ACTION_CSUM; 3621 entry->csum_flags = tcf_csum_update_flags(act); 3622 } else if (is_tcf_skbedit_mark(act)) { 3623 entry->id = FLOW_ACTION_MARK; 3624 entry->mark = tcf_skbedit_mark(act); 3625 } else if (is_tcf_sample(act)) { 3626 entry->id = FLOW_ACTION_SAMPLE; 3627 entry->sample.trunc_size = tcf_sample_trunc_size(act); 3628 entry->sample.truncate = tcf_sample_truncate(act); 3629 entry->sample.rate = tcf_sample_rate(act); 3630 tcf_sample_get_group(entry, act); 3631 } else if (is_tcf_police(act)) { 3632 entry->id = FLOW_ACTION_POLICE; 3633 entry->police.burst = tcf_police_tcfp_burst(act); 3634 entry->police.rate_bytes_ps = 3635 tcf_police_rate_bytes_ps(act); 3636 } else if (is_tcf_ct(act)) { 3637 entry->id = FLOW_ACTION_CT; 3638 entry->ct.action = tcf_ct_action(act); 3639 entry->ct.zone = tcf_ct_zone(act); 3640 entry->ct.flow_table = tcf_ct_ft(act); 3641 } else if (is_tcf_mpls(act)) { 3642 switch (tcf_mpls_action(act)) { 3643 case TCA_MPLS_ACT_PUSH: 3644 entry->id = FLOW_ACTION_MPLS_PUSH; 3645 entry->mpls_push.proto = tcf_mpls_proto(act); 3646 entry->mpls_push.label = tcf_mpls_label(act); 3647 entry->mpls_push.tc = tcf_mpls_tc(act); 3648 entry->mpls_push.bos = tcf_mpls_bos(act); 3649 entry->mpls_push.ttl = tcf_mpls_ttl(act); 3650 break; 3651 case TCA_MPLS_ACT_POP: 3652 entry->id = FLOW_ACTION_MPLS_POP; 3653 entry->mpls_pop.proto = tcf_mpls_proto(act); 3654 break; 3655 case TCA_MPLS_ACT_MODIFY: 3656 entry->id = FLOW_ACTION_MPLS_MANGLE; 3657 entry->mpls_mangle.label = tcf_mpls_label(act); 3658 entry->mpls_mangle.tc = tcf_mpls_tc(act); 3659 entry->mpls_mangle.bos = tcf_mpls_bos(act); 3660 entry->mpls_mangle.ttl = tcf_mpls_ttl(act); 3661 break; 3662 default: 3663 goto err_out_locked; 3664 } 3665 } else if (is_tcf_skbedit_ptype(act)) { 3666 entry->id = FLOW_ACTION_PTYPE; 3667 entry->ptype = tcf_skbedit_ptype(act); 3668 } else if (is_tcf_skbedit_priority(act)) { 3669 entry->id = FLOW_ACTION_PRIORITY; 3670 entry->priority = tcf_skbedit_priority(act); 3671 } else { 3672 err = -EOPNOTSUPP; 3673 goto err_out_locked; 3674 } 3675 spin_unlock_bh(&act->tcfa_lock); 3676 3677 if (!is_tcf_pedit(act)) 3678 j++; 3679 } 3680 3681 err_out: 3682 if (err) 3683 tc_cleanup_flow_action(flow_action); 3684 3685 return err; 3686 err_out_locked: 3687 spin_unlock_bh(&act->tcfa_lock); 3688 goto err_out; 3689 } 3690 EXPORT_SYMBOL(tc_setup_flow_action); 3691 3692 unsigned int tcf_exts_num_actions(struct tcf_exts *exts) 3693 { 3694 unsigned int num_acts = 0; 3695 struct tc_action *act; 3696 int i; 3697 3698 tcf_exts_for_each_action(i, act, exts) { 3699 if (is_tcf_pedit(act)) 3700 num_acts += tcf_pedit_nkeys(act); 3701 else 3702 num_acts++; 3703 } 3704 return num_acts; 3705 } 3706 EXPORT_SYMBOL(tcf_exts_num_actions); 3707 3708 static __net_init int tcf_net_init(struct net *net) 3709 { 3710 struct tcf_net *tn = net_generic(net, tcf_net_id); 3711 3712 spin_lock_init(&tn->idr_lock); 3713 idr_init(&tn->idr); 3714 return 0; 3715 } 3716 3717 static void __net_exit tcf_net_exit(struct net *net) 3718 { 3719 struct tcf_net *tn = net_generic(net, tcf_net_id); 3720 3721 idr_destroy(&tn->idr); 3722 } 3723 3724 static struct pernet_operations tcf_net_ops = { 3725 .init = tcf_net_init, 3726 .exit = tcf_net_exit, 3727 .id = &tcf_net_id, 3728 .size = sizeof(struct tcf_net), 3729 }; 3730 3731 static struct flow_indr_block_entry block_entry = { 3732 .cb = tc_indr_block_get_and_cmd, 3733 .list = LIST_HEAD_INIT(block_entry.list), 3734 }; 3735 3736 static int __init tc_filter_init(void) 3737 { 3738 int err; 3739 3740 tc_filter_wq = alloc_ordered_workqueue("tc_filter_workqueue", 0); 3741 if (!tc_filter_wq) 3742 return -ENOMEM; 3743 3744 err = register_pernet_subsys(&tcf_net_ops); 3745 if (err) 3746 goto err_register_pernet_subsys; 3747 3748 flow_indr_add_block_cb(&block_entry); 3749 3750 rtnl_register(PF_UNSPEC, RTM_NEWTFILTER, tc_new_tfilter, NULL, 3751 RTNL_FLAG_DOIT_UNLOCKED); 3752 rtnl_register(PF_UNSPEC, RTM_DELTFILTER, tc_del_tfilter, NULL, 3753 RTNL_FLAG_DOIT_UNLOCKED); 3754 rtnl_register(PF_UNSPEC, RTM_GETTFILTER, tc_get_tfilter, 3755 tc_dump_tfilter, RTNL_FLAG_DOIT_UNLOCKED); 3756 rtnl_register(PF_UNSPEC, RTM_NEWCHAIN, tc_ctl_chain, NULL, 0); 3757 rtnl_register(PF_UNSPEC, RTM_DELCHAIN, tc_ctl_chain, NULL, 0); 3758 rtnl_register(PF_UNSPEC, RTM_GETCHAIN, tc_ctl_chain, 3759 tc_dump_chain, 0); 3760 3761 return 0; 3762 3763 err_register_pernet_subsys: 3764 destroy_workqueue(tc_filter_wq); 3765 return err; 3766 } 3767 3768 subsys_initcall(tc_filter_init); 3769