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