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v5.4
   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
  43extern const struct nla_policy rtm_tca_policy[TCA_MAX + 1];
  44
  45/* The list of all installed classifier types */
  46static LIST_HEAD(tcf_proto_base);
  47
  48/* Protects list of registered TC modules. It is pure SMP lock. */
  49static DEFINE_RWLOCK(cls_mod_lock);
  50
  51static 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
  57static 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
  68static 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
  76static 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
  96static void
  97tcf_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
 109static 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
 127static const struct tcf_proto_ops *
 128tcf_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
 159int 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;
 171out:
 172	write_unlock(&cls_mod_lock);
 173	return rc;
 174}
 175EXPORT_SYMBOL(register_tcf_proto_ops);
 176
 177static struct workqueue_struct *tc_filter_wq;
 178
 179int 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}
 201EXPORT_SYMBOL(unregister_tcf_proto_ops);
 202
 203bool 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}
 208EXPORT_SYMBOL(tcf_queue_work);
 209
 210/* Select new prio value from the range, managed by kernel. */
 211
 212static 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
 222static 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
 230static 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
 250static 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
 281errout:
 282	kfree(tp);
 283	return ERR_PTR(err);
 284}
 285
 286static void tcf_proto_get(struct tcf_proto *tp)
 287{
 288	refcount_inc(&tp->refcnt);
 289}
 290
 291static void tcf_chain_put(struct tcf_chain *chain);
 292
 293static 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
 304static 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
 311static int walker_check_empty(struct tcf_proto *tp, void *fh,
 312			      struct tcf_walker *arg)
 313{
 314	if (fh) {
 315		arg->nonempty = true;
 316		return -1;
 317	}
 318	return 0;
 319}
 320
 321static bool tcf_proto_is_empty(struct tcf_proto *tp, bool rtnl_held)
 322{
 323	struct tcf_walker walker = { .fn = walker_check_empty, };
 324
 325	if (tp->ops->walk) {
 326		tp->ops->walk(tp, &walker, rtnl_held);
 327		return !walker.nonempty;
 328	}
 329	return true;
 330}
 331
 332static bool tcf_proto_check_delete(struct tcf_proto *tp, bool rtnl_held)
 333{
 334	spin_lock(&tp->lock);
 335	if (tcf_proto_is_empty(tp, rtnl_held))
 336		tp->deleting = true;
 337	spin_unlock(&tp->lock);
 338	return tp->deleting;
 339}
 340
 341static void tcf_proto_mark_delete(struct tcf_proto *tp)
 342{
 343	spin_lock(&tp->lock);
 344	tp->deleting = true;
 345	spin_unlock(&tp->lock);
 346}
 347
 348static bool tcf_proto_is_deleting(struct tcf_proto *tp)
 349{
 350	bool deleting;
 351
 352	spin_lock(&tp->lock);
 353	deleting = tp->deleting;
 354	spin_unlock(&tp->lock);
 355
 356	return deleting;
 357}
 358
 359#define ASSERT_BLOCK_LOCKED(block)					\
 360	lockdep_assert_held(&(block)->lock)
 361
 362struct tcf_filter_chain_list_item {
 363	struct list_head list;
 364	tcf_chain_head_change_t *chain_head_change;
 365	void *chain_head_change_priv;
 366};
 367
 368static struct tcf_chain *tcf_chain_create(struct tcf_block *block,
 369					  u32 chain_index)
 370{
 371	struct tcf_chain *chain;
 372
 373	ASSERT_BLOCK_LOCKED(block);
 374
 375	chain = kzalloc(sizeof(*chain), GFP_KERNEL);
 376	if (!chain)
 377		return NULL;
 378	list_add_tail(&chain->list, &block->chain_list);
 379	mutex_init(&chain->filter_chain_lock);
 380	chain->block = block;
 381	chain->index = chain_index;
 382	chain->refcnt = 1;
 383	if (!chain->index)
 384		block->chain0.chain = chain;
 385	return chain;
 386}
 387
 388static void tcf_chain_head_change_item(struct tcf_filter_chain_list_item *item,
 389				       struct tcf_proto *tp_head)
 390{
 391	if (item->chain_head_change)
 392		item->chain_head_change(tp_head, item->chain_head_change_priv);
 393}
 394
 395static void tcf_chain0_head_change(struct tcf_chain *chain,
 396				   struct tcf_proto *tp_head)
 397{
 398	struct tcf_filter_chain_list_item *item;
 399	struct tcf_block *block = chain->block;
 400
 401	if (chain->index)
 402		return;
 403
 404	mutex_lock(&block->lock);
 405	list_for_each_entry(item, &block->chain0.filter_chain_list, list)
 406		tcf_chain_head_change_item(item, tp_head);
 407	mutex_unlock(&block->lock);
 408}
 409
 410/* Returns true if block can be safely freed. */
 411
 412static bool tcf_chain_detach(struct tcf_chain *chain)
 413{
 414	struct tcf_block *block = chain->block;
 415
 416	ASSERT_BLOCK_LOCKED(block);
 417
 418	list_del(&chain->list);
 419	if (!chain->index)
 420		block->chain0.chain = NULL;
 421
 422	if (list_empty(&block->chain_list) &&
 423	    refcount_read(&block->refcnt) == 0)
 424		return true;
 425
 426	return false;
 427}
 428
 429static void tcf_block_destroy(struct tcf_block *block)
 430{
 431	mutex_destroy(&block->lock);
 432	mutex_destroy(&block->proto_destroy_lock);
 433	kfree_rcu(block, rcu);
 434}
 435
 436static void tcf_chain_destroy(struct tcf_chain *chain, bool free_block)
 437{
 438	struct tcf_block *block = chain->block;
 439
 440	mutex_destroy(&chain->filter_chain_lock);
 441	kfree_rcu(chain, rcu);
 442	if (free_block)
 443		tcf_block_destroy(block);
 444}
 445
 446static void tcf_chain_hold(struct tcf_chain *chain)
 447{
 448	ASSERT_BLOCK_LOCKED(chain->block);
 449
 450	++chain->refcnt;
 451}
 452
 453static bool tcf_chain_held_by_acts_only(struct tcf_chain *chain)
 454{
 455	ASSERT_BLOCK_LOCKED(chain->block);
 456
 457	/* In case all the references are action references, this
 458	 * chain should not be shown to the user.
 459	 */
 460	return chain->refcnt == chain->action_refcnt;
 461}
 462
 463static struct tcf_chain *tcf_chain_lookup(struct tcf_block *block,
 464					  u32 chain_index)
 465{
 466	struct tcf_chain *chain;
 467
 468	ASSERT_BLOCK_LOCKED(block);
 469
 470	list_for_each_entry(chain, &block->chain_list, list) {
 471		if (chain->index == chain_index)
 472			return chain;
 473	}
 474	return NULL;
 475}
 476
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 477static int tc_chain_notify(struct tcf_chain *chain, struct sk_buff *oskb,
 478			   u32 seq, u16 flags, int event, bool unicast);
 479
 480static struct tcf_chain *__tcf_chain_get(struct tcf_block *block,
 481					 u32 chain_index, bool create,
 482					 bool by_act)
 483{
 484	struct tcf_chain *chain = NULL;
 485	bool is_first_reference;
 486
 487	mutex_lock(&block->lock);
 488	chain = tcf_chain_lookup(block, chain_index);
 489	if (chain) {
 490		tcf_chain_hold(chain);
 491	} else {
 492		if (!create)
 493			goto errout;
 494		chain = tcf_chain_create(block, chain_index);
 495		if (!chain)
 496			goto errout;
 497	}
 498
 499	if (by_act)
 500		++chain->action_refcnt;
 501	is_first_reference = chain->refcnt - chain->action_refcnt == 1;
 502	mutex_unlock(&block->lock);
 503
 504	/* Send notification only in case we got the first
 505	 * non-action reference. Until then, the chain acts only as
 506	 * a placeholder for actions pointing to it and user ought
 507	 * not know about them.
 508	 */
 509	if (is_first_reference && !by_act)
 510		tc_chain_notify(chain, NULL, 0, NLM_F_CREATE | NLM_F_EXCL,
 511				RTM_NEWCHAIN, false);
 512
 513	return chain;
 514
 515errout:
 516	mutex_unlock(&block->lock);
 517	return chain;
 518}
 519
 520static struct tcf_chain *tcf_chain_get(struct tcf_block *block, u32 chain_index,
 521				       bool create)
 522{
 523	return __tcf_chain_get(block, chain_index, create, false);
 524}
 525
 526struct tcf_chain *tcf_chain_get_by_act(struct tcf_block *block, u32 chain_index)
 527{
 528	return __tcf_chain_get(block, chain_index, true, true);
 529}
 530EXPORT_SYMBOL(tcf_chain_get_by_act);
 531
 532static void tc_chain_tmplt_del(const struct tcf_proto_ops *tmplt_ops,
 533			       void *tmplt_priv);
 534static int tc_chain_notify_delete(const struct tcf_proto_ops *tmplt_ops,
 535				  void *tmplt_priv, u32 chain_index,
 536				  struct tcf_block *block, struct sk_buff *oskb,
 537				  u32 seq, u16 flags, bool unicast);
 538
 539static void __tcf_chain_put(struct tcf_chain *chain, bool by_act,
 540			    bool explicitly_created)
 541{
 542	struct tcf_block *block = chain->block;
 543	const struct tcf_proto_ops *tmplt_ops;
 544	bool free_block = false;
 545	unsigned int refcnt;
 546	void *tmplt_priv;
 547
 548	mutex_lock(&block->lock);
 549	if (explicitly_created) {
 550		if (!chain->explicitly_created) {
 551			mutex_unlock(&block->lock);
 552			return;
 553		}
 554		chain->explicitly_created = false;
 555	}
 556
 557	if (by_act)
 558		chain->action_refcnt--;
 559
 560	/* tc_chain_notify_delete can't be called while holding block lock.
 561	 * However, when block is unlocked chain can be changed concurrently, so
 562	 * save these to temporary variables.
 563	 */
 564	refcnt = --chain->refcnt;
 565	tmplt_ops = chain->tmplt_ops;
 566	tmplt_priv = chain->tmplt_priv;
 567
 568	/* The last dropped non-action reference will trigger notification. */
 569	if (refcnt - chain->action_refcnt == 0 && !by_act) {
 570		tc_chain_notify_delete(tmplt_ops, tmplt_priv, chain->index,
 571				       block, NULL, 0, 0, false);
 572		/* Last reference to chain, no need to lock. */
 573		chain->flushing = false;
 574	}
 575
 576	if (refcnt == 0)
 577		free_block = tcf_chain_detach(chain);
 578	mutex_unlock(&block->lock);
 579
 580	if (refcnt == 0) {
 581		tc_chain_tmplt_del(tmplt_ops, tmplt_priv);
 582		tcf_chain_destroy(chain, free_block);
 583	}
 584}
 585
 586static void tcf_chain_put(struct tcf_chain *chain)
 587{
 588	__tcf_chain_put(chain, false, false);
 589}
 590
 591void tcf_chain_put_by_act(struct tcf_chain *chain)
 592{
 593	__tcf_chain_put(chain, true, false);
 594}
 595EXPORT_SYMBOL(tcf_chain_put_by_act);
 596
 597static void tcf_chain_put_explicitly_created(struct tcf_chain *chain)
 598{
 599	__tcf_chain_put(chain, false, true);
 600}
 601
 602static void tcf_chain_flush(struct tcf_chain *chain, bool rtnl_held)
 603{
 604	struct tcf_proto *tp, *tp_next;
 605
 606	mutex_lock(&chain->filter_chain_lock);
 607	tp = tcf_chain_dereference(chain->filter_chain, chain);
 608	while (tp) {
 609		tp_next = rcu_dereference_protected(tp->next, 1);
 610		tcf_proto_signal_destroying(chain, tp);
 611		tp = tp_next;
 612	}
 613	tp = tcf_chain_dereference(chain->filter_chain, chain);
 614	RCU_INIT_POINTER(chain->filter_chain, NULL);
 615	tcf_chain0_head_change(chain, NULL);
 616	chain->flushing = true;
 617	mutex_unlock(&chain->filter_chain_lock);
 618
 619	while (tp) {
 620		tp_next = rcu_dereference_protected(tp->next, 1);
 621		tcf_proto_put(tp, rtnl_held, NULL);
 622		tp = tp_next;
 623	}
 624}
 625
 626static int tcf_block_setup(struct tcf_block *block,
 627			   struct flow_block_offload *bo);
 628
 629static void tc_indr_block_ing_cmd(struct net_device *dev,
 630				  struct tcf_block *block,
 631				  flow_indr_block_bind_cb_t *cb,
 632				  void *cb_priv,
 633				  enum flow_block_command command)
 634{
 635	struct flow_block_offload bo = {
 636		.command	= command,
 637		.binder_type	= FLOW_BLOCK_BINDER_TYPE_CLSACT_INGRESS,
 638		.net		= dev_net(dev),
 639		.block_shared	= tcf_block_non_null_shared(block),
 640	};
 641	INIT_LIST_HEAD(&bo.cb_list);
 642
 643	if (!block)
 644		return;
 645
 646	bo.block = &block->flow_block;
 647
 648	down_write(&block->cb_lock);
 649	cb(dev, cb_priv, TC_SETUP_BLOCK, &bo);
 650
 651	tcf_block_setup(block, &bo);
 652	up_write(&block->cb_lock);
 653}
 654
 655static struct tcf_block *tc_dev_ingress_block(struct net_device *dev)
 656{
 657	const struct Qdisc_class_ops *cops;
 658	struct Qdisc *qdisc;
 659
 660	if (!dev_ingress_queue(dev))
 661		return NULL;
 662
 663	qdisc = dev_ingress_queue(dev)->qdisc_sleeping;
 664	if (!qdisc)
 665		return NULL;
 666
 667	cops = qdisc->ops->cl_ops;
 668	if (!cops)
 669		return NULL;
 670
 671	if (!cops->tcf_block)
 672		return NULL;
 673
 674	return cops->tcf_block(qdisc, TC_H_MIN_INGRESS, NULL);
 675}
 676
 677static void tc_indr_block_get_and_ing_cmd(struct net_device *dev,
 678					  flow_indr_block_bind_cb_t *cb,
 679					  void *cb_priv,
 680					  enum flow_block_command command)
 681{
 682	struct tcf_block *block = tc_dev_ingress_block(dev);
 683
 684	tc_indr_block_ing_cmd(dev, block, cb, cb_priv, command);
 685}
 686
 687static void tc_indr_block_call(struct tcf_block *block,
 688			       struct net_device *dev,
 689			       struct tcf_block_ext_info *ei,
 690			       enum flow_block_command command,
 691			       struct netlink_ext_ack *extack)
 692{
 693	struct flow_block_offload bo = {
 694		.command	= command,
 695		.binder_type	= ei->binder_type,
 696		.net		= dev_net(dev),
 697		.block		= &block->flow_block,
 698		.block_shared	= tcf_block_shared(block),
 699		.extack		= extack,
 700	};
 701	INIT_LIST_HEAD(&bo.cb_list);
 702
 703	flow_indr_block_call(dev, &bo, command);
 704	tcf_block_setup(block, &bo);
 
 
 
 
 
 
 
 
 
 705}
 706
 707static bool tcf_block_offload_in_use(struct tcf_block *block)
 708{
 709	return atomic_read(&block->offloadcnt);
 710}
 711
 712static int tcf_block_offload_cmd(struct tcf_block *block,
 713				 struct net_device *dev,
 714				 struct tcf_block_ext_info *ei,
 715				 enum flow_block_command command,
 716				 struct netlink_ext_ack *extack)
 717{
 718	struct flow_block_offload bo = {};
 719	int err;
 720
 721	bo.net = dev_net(dev);
 722	bo.command = command;
 723	bo.binder_type = ei->binder_type;
 724	bo.block = &block->flow_block;
 725	bo.block_shared = tcf_block_shared(block);
 726	bo.extack = extack;
 727	INIT_LIST_HEAD(&bo.cb_list);
 728
 729	err = dev->netdev_ops->ndo_setup_tc(dev, TC_SETUP_BLOCK, &bo);
 730	if (err < 0)
 731		return err;
 
 
 
 
 
 
 
 
 
 
 
 
 
 732
 733	return tcf_block_setup(block, &bo);
 734}
 735
 736static int tcf_block_offload_bind(struct tcf_block *block, struct Qdisc *q,
 737				  struct tcf_block_ext_info *ei,
 738				  struct netlink_ext_ack *extack)
 739{
 740	struct net_device *dev = q->dev_queue->dev;
 741	int err;
 742
 743	down_write(&block->cb_lock);
 744	if (!dev->netdev_ops->ndo_setup_tc)
 745		goto no_offload_dev_inc;
 746
 747	/* If tc offload feature is disabled and the block we try to bind
 748	 * to already has some offloaded filters, forbid to bind.
 749	 */
 750	if (!tc_can_offload(dev) && tcf_block_offload_in_use(block)) {
 
 
 751		NL_SET_ERR_MSG(extack, "Bind to offloaded block failed as dev has offload disabled");
 752		err = -EOPNOTSUPP;
 753		goto err_unlock;
 754	}
 755
 756	err = tcf_block_offload_cmd(block, dev, ei, FLOW_BLOCK_BIND, extack);
 757	if (err == -EOPNOTSUPP)
 758		goto no_offload_dev_inc;
 759	if (err)
 760		goto err_unlock;
 761
 762	tc_indr_block_call(block, dev, ei, FLOW_BLOCK_BIND, extack);
 763	up_write(&block->cb_lock);
 764	return 0;
 765
 766no_offload_dev_inc:
 767	if (tcf_block_offload_in_use(block)) {
 768		err = -EOPNOTSUPP;
 769		goto err_unlock;
 770	}
 771	err = 0;
 772	block->nooffloaddevcnt++;
 773	tc_indr_block_call(block, dev, ei, FLOW_BLOCK_BIND, extack);
 774err_unlock:
 775	up_write(&block->cb_lock);
 776	return err;
 777}
 778
 779static void tcf_block_offload_unbind(struct tcf_block *block, struct Qdisc *q,
 780				     struct tcf_block_ext_info *ei)
 781{
 782	struct net_device *dev = q->dev_queue->dev;
 783	int err;
 784
 785	down_write(&block->cb_lock);
 786	tc_indr_block_call(block, dev, ei, FLOW_BLOCK_UNBIND, NULL);
 787
 788	if (!dev->netdev_ops->ndo_setup_tc)
 789		goto no_offload_dev_dec;
 790	err = tcf_block_offload_cmd(block, dev, ei, FLOW_BLOCK_UNBIND, NULL);
 791	if (err == -EOPNOTSUPP)
 792		goto no_offload_dev_dec;
 793	up_write(&block->cb_lock);
 794	return;
 795
 796no_offload_dev_dec:
 797	WARN_ON(block->nooffloaddevcnt-- == 0);
 798	up_write(&block->cb_lock);
 799}
 800
 801static int
 802tcf_chain0_head_change_cb_add(struct tcf_block *block,
 803			      struct tcf_block_ext_info *ei,
 804			      struct netlink_ext_ack *extack)
 805{
 806	struct tcf_filter_chain_list_item *item;
 807	struct tcf_chain *chain0;
 808
 809	item = kmalloc(sizeof(*item), GFP_KERNEL);
 810	if (!item) {
 811		NL_SET_ERR_MSG(extack, "Memory allocation for head change callback item failed");
 812		return -ENOMEM;
 813	}
 814	item->chain_head_change = ei->chain_head_change;
 815	item->chain_head_change_priv = ei->chain_head_change_priv;
 816
 817	mutex_lock(&block->lock);
 818	chain0 = block->chain0.chain;
 819	if (chain0)
 820		tcf_chain_hold(chain0);
 821	else
 822		list_add(&item->list, &block->chain0.filter_chain_list);
 823	mutex_unlock(&block->lock);
 824
 825	if (chain0) {
 826		struct tcf_proto *tp_head;
 827
 828		mutex_lock(&chain0->filter_chain_lock);
 829
 830		tp_head = tcf_chain_dereference(chain0->filter_chain, chain0);
 831		if (tp_head)
 832			tcf_chain_head_change_item(item, tp_head);
 833
 834		mutex_lock(&block->lock);
 835		list_add(&item->list, &block->chain0.filter_chain_list);
 836		mutex_unlock(&block->lock);
 837
 838		mutex_unlock(&chain0->filter_chain_lock);
 839		tcf_chain_put(chain0);
 840	}
 841
 842	return 0;
 843}
 844
 845static void
 846tcf_chain0_head_change_cb_del(struct tcf_block *block,
 847			      struct tcf_block_ext_info *ei)
 848{
 849	struct tcf_filter_chain_list_item *item;
 850
 851	mutex_lock(&block->lock);
 852	list_for_each_entry(item, &block->chain0.filter_chain_list, list) {
 853		if ((!ei->chain_head_change && !ei->chain_head_change_priv) ||
 854		    (item->chain_head_change == ei->chain_head_change &&
 855		     item->chain_head_change_priv == ei->chain_head_change_priv)) {
 856			if (block->chain0.chain)
 857				tcf_chain_head_change_item(item, NULL);
 858			list_del(&item->list);
 859			mutex_unlock(&block->lock);
 860
 861			kfree(item);
 862			return;
 863		}
 864	}
 865	mutex_unlock(&block->lock);
 866	WARN_ON(1);
 867}
 868
 869struct tcf_net {
 870	spinlock_t idr_lock; /* Protects idr */
 871	struct idr idr;
 872};
 873
 874static unsigned int tcf_net_id;
 875
 876static int tcf_block_insert(struct tcf_block *block, struct net *net,
 877			    struct netlink_ext_ack *extack)
 878{
 879	struct tcf_net *tn = net_generic(net, tcf_net_id);
 880	int err;
 881
 882	idr_preload(GFP_KERNEL);
 883	spin_lock(&tn->idr_lock);
 884	err = idr_alloc_u32(&tn->idr, block, &block->index, block->index,
 885			    GFP_NOWAIT);
 886	spin_unlock(&tn->idr_lock);
 887	idr_preload_end();
 888
 889	return err;
 890}
 891
 892static void tcf_block_remove(struct tcf_block *block, struct net *net)
 893{
 894	struct tcf_net *tn = net_generic(net, tcf_net_id);
 895
 896	spin_lock(&tn->idr_lock);
 897	idr_remove(&tn->idr, block->index);
 898	spin_unlock(&tn->idr_lock);
 899}
 900
 901static struct tcf_block *tcf_block_create(struct net *net, struct Qdisc *q,
 902					  u32 block_index,
 903					  struct netlink_ext_ack *extack)
 904{
 905	struct tcf_block *block;
 906
 907	block = kzalloc(sizeof(*block), GFP_KERNEL);
 908	if (!block) {
 909		NL_SET_ERR_MSG(extack, "Memory allocation for block failed");
 910		return ERR_PTR(-ENOMEM);
 911	}
 912	mutex_init(&block->lock);
 913	mutex_init(&block->proto_destroy_lock);
 914	init_rwsem(&block->cb_lock);
 915	flow_block_init(&block->flow_block);
 916	INIT_LIST_HEAD(&block->chain_list);
 917	INIT_LIST_HEAD(&block->owner_list);
 918	INIT_LIST_HEAD(&block->chain0.filter_chain_list);
 919
 920	refcount_set(&block->refcnt, 1);
 921	block->net = net;
 922	block->index = block_index;
 923
 924	/* Don't store q pointer for blocks which are shared */
 925	if (!tcf_block_shared(block))
 926		block->q = q;
 927	return block;
 928}
 929
 930static struct tcf_block *tcf_block_lookup(struct net *net, u32 block_index)
 931{
 932	struct tcf_net *tn = net_generic(net, tcf_net_id);
 933
 934	return idr_find(&tn->idr, block_index);
 935}
 936
 937static struct tcf_block *tcf_block_refcnt_get(struct net *net, u32 block_index)
 938{
 939	struct tcf_block *block;
 940
 941	rcu_read_lock();
 942	block = tcf_block_lookup(net, block_index);
 943	if (block && !refcount_inc_not_zero(&block->refcnt))
 944		block = NULL;
 945	rcu_read_unlock();
 946
 947	return block;
 948}
 949
 950static struct tcf_chain *
 951__tcf_get_next_chain(struct tcf_block *block, struct tcf_chain *chain)
 952{
 953	mutex_lock(&block->lock);
 954	if (chain)
 955		chain = list_is_last(&chain->list, &block->chain_list) ?
 956			NULL : list_next_entry(chain, list);
 957	else
 958		chain = list_first_entry_or_null(&block->chain_list,
 959						 struct tcf_chain, list);
 960
 961	/* skip all action-only chains */
 962	while (chain && tcf_chain_held_by_acts_only(chain))
 963		chain = list_is_last(&chain->list, &block->chain_list) ?
 964			NULL : list_next_entry(chain, list);
 965
 966	if (chain)
 967		tcf_chain_hold(chain);
 968	mutex_unlock(&block->lock);
 969
 970	return chain;
 971}
 972
 973/* Function to be used by all clients that want to iterate over all chains on
 974 * block. It properly obtains block->lock and takes reference to chain before
 975 * returning it. Users of this function must be tolerant to concurrent chain
 976 * insertion/deletion or ensure that no concurrent chain modification is
 977 * possible. Note that all netlink dump callbacks cannot guarantee to provide
 978 * consistent dump because rtnl lock is released each time skb is filled with
 979 * data and sent to user-space.
 980 */
 981
 982struct tcf_chain *
 983tcf_get_next_chain(struct tcf_block *block, struct tcf_chain *chain)
 984{
 985	struct tcf_chain *chain_next = __tcf_get_next_chain(block, chain);
 986
 987	if (chain)
 988		tcf_chain_put(chain);
 989
 990	return chain_next;
 991}
 992EXPORT_SYMBOL(tcf_get_next_chain);
 993
 994static struct tcf_proto *
 995__tcf_get_next_proto(struct tcf_chain *chain, struct tcf_proto *tp)
 996{
 997	u32 prio = 0;
 998
 999	ASSERT_RTNL();
1000	mutex_lock(&chain->filter_chain_lock);
1001
1002	if (!tp) {
1003		tp = tcf_chain_dereference(chain->filter_chain, chain);
1004	} else if (tcf_proto_is_deleting(tp)) {
1005		/* 'deleting' flag is set and chain->filter_chain_lock was
1006		 * unlocked, which means next pointer could be invalid. Restart
1007		 * search.
1008		 */
1009		prio = tp->prio + 1;
1010		tp = tcf_chain_dereference(chain->filter_chain, chain);
1011
1012		for (; tp; tp = tcf_chain_dereference(tp->next, chain))
1013			if (!tp->deleting && tp->prio >= prio)
1014				break;
1015	} else {
1016		tp = tcf_chain_dereference(tp->next, chain);
1017	}
1018
1019	if (tp)
1020		tcf_proto_get(tp);
1021
1022	mutex_unlock(&chain->filter_chain_lock);
1023
1024	return tp;
1025}
1026
1027/* Function to be used by all clients that want to iterate over all tp's on
1028 * chain. Users of this function must be tolerant to concurrent tp
1029 * insertion/deletion or ensure that no concurrent chain modification is
1030 * possible. Note that all netlink dump callbacks cannot guarantee to provide
1031 * consistent dump because rtnl lock is released each time skb is filled with
1032 * data and sent to user-space.
1033 */
1034
1035struct tcf_proto *
1036tcf_get_next_proto(struct tcf_chain *chain, struct tcf_proto *tp,
1037		   bool rtnl_held)
1038{
1039	struct tcf_proto *tp_next = __tcf_get_next_proto(chain, tp);
1040
1041	if (tp)
1042		tcf_proto_put(tp, rtnl_held, NULL);
1043
1044	return tp_next;
1045}
1046EXPORT_SYMBOL(tcf_get_next_proto);
1047
1048static void tcf_block_flush_all_chains(struct tcf_block *block, bool rtnl_held)
1049{
1050	struct tcf_chain *chain;
1051
1052	/* Last reference to block. At this point chains cannot be added or
1053	 * removed concurrently.
1054	 */
1055	for (chain = tcf_get_next_chain(block, NULL);
1056	     chain;
1057	     chain = tcf_get_next_chain(block, chain)) {
1058		tcf_chain_put_explicitly_created(chain);
1059		tcf_chain_flush(chain, rtnl_held);
1060	}
1061}
1062
1063/* Lookup Qdisc and increments its reference counter.
1064 * Set parent, if necessary.
1065 */
1066
1067static int __tcf_qdisc_find(struct net *net, struct Qdisc **q,
1068			    u32 *parent, int ifindex, bool rtnl_held,
1069			    struct netlink_ext_ack *extack)
1070{
1071	const struct Qdisc_class_ops *cops;
1072	struct net_device *dev;
1073	int err = 0;
1074
1075	if (ifindex == TCM_IFINDEX_MAGIC_BLOCK)
1076		return 0;
1077
1078	rcu_read_lock();
1079
1080	/* Find link */
1081	dev = dev_get_by_index_rcu(net, ifindex);
1082	if (!dev) {
1083		rcu_read_unlock();
1084		return -ENODEV;
1085	}
1086
1087	/* Find qdisc */
1088	if (!*parent) {
1089		*q = dev->qdisc;
1090		*parent = (*q)->handle;
1091	} else {
1092		*q = qdisc_lookup_rcu(dev, TC_H_MAJ(*parent));
1093		if (!*q) {
1094			NL_SET_ERR_MSG(extack, "Parent Qdisc doesn't exists");
1095			err = -EINVAL;
1096			goto errout_rcu;
1097		}
1098	}
1099
1100	*q = qdisc_refcount_inc_nz(*q);
1101	if (!*q) {
1102		NL_SET_ERR_MSG(extack, "Parent Qdisc doesn't exists");
1103		err = -EINVAL;
1104		goto errout_rcu;
1105	}
1106
1107	/* Is it classful? */
1108	cops = (*q)->ops->cl_ops;
1109	if (!cops) {
1110		NL_SET_ERR_MSG(extack, "Qdisc not classful");
1111		err = -EINVAL;
1112		goto errout_qdisc;
1113	}
1114
1115	if (!cops->tcf_block) {
1116		NL_SET_ERR_MSG(extack, "Class doesn't support blocks");
1117		err = -EOPNOTSUPP;
1118		goto errout_qdisc;
1119	}
1120
1121errout_rcu:
1122	/* At this point we know that qdisc is not noop_qdisc,
1123	 * which means that qdisc holds a reference to net_device
1124	 * and we hold a reference to qdisc, so it is safe to release
1125	 * rcu read lock.
1126	 */
1127	rcu_read_unlock();
1128	return err;
1129
1130errout_qdisc:
1131	rcu_read_unlock();
1132
1133	if (rtnl_held)
1134		qdisc_put(*q);
1135	else
1136		qdisc_put_unlocked(*q);
1137	*q = NULL;
1138
1139	return err;
1140}
1141
1142static int __tcf_qdisc_cl_find(struct Qdisc *q, u32 parent, unsigned long *cl,
1143			       int ifindex, struct netlink_ext_ack *extack)
1144{
1145	if (ifindex == TCM_IFINDEX_MAGIC_BLOCK)
1146		return 0;
1147
1148	/* Do we search for filter, attached to class? */
1149	if (TC_H_MIN(parent)) {
1150		const struct Qdisc_class_ops *cops = q->ops->cl_ops;
1151
1152		*cl = cops->find(q, parent);
1153		if (*cl == 0) {
1154			NL_SET_ERR_MSG(extack, "Specified class doesn't exist");
1155			return -ENOENT;
1156		}
1157	}
1158
1159	return 0;
1160}
1161
1162static struct tcf_block *__tcf_block_find(struct net *net, struct Qdisc *q,
1163					  unsigned long cl, int ifindex,
1164					  u32 block_index,
1165					  struct netlink_ext_ack *extack)
1166{
1167	struct tcf_block *block;
1168
1169	if (ifindex == TCM_IFINDEX_MAGIC_BLOCK) {
1170		block = tcf_block_refcnt_get(net, block_index);
1171		if (!block) {
1172			NL_SET_ERR_MSG(extack, "Block of given index was not found");
1173			return ERR_PTR(-EINVAL);
1174		}
1175	} else {
1176		const struct Qdisc_class_ops *cops = q->ops->cl_ops;
1177
1178		block = cops->tcf_block(q, cl, extack);
1179		if (!block)
1180			return ERR_PTR(-EINVAL);
1181
1182		if (tcf_block_shared(block)) {
1183			NL_SET_ERR_MSG(extack, "This filter block is shared. Please use the block index to manipulate the filters");
1184			return ERR_PTR(-EOPNOTSUPP);
1185		}
1186
1187		/* Always take reference to block in order to support execution
1188		 * of rules update path of cls API without rtnl lock. Caller
1189		 * must release block when it is finished using it. 'if' block
1190		 * of this conditional obtain reference to block by calling
1191		 * tcf_block_refcnt_get().
1192		 */
1193		refcount_inc(&block->refcnt);
1194	}
1195
1196	return block;
1197}
1198
1199static void __tcf_block_put(struct tcf_block *block, struct Qdisc *q,
1200			    struct tcf_block_ext_info *ei, bool rtnl_held)
1201{
1202	if (refcount_dec_and_mutex_lock(&block->refcnt, &block->lock)) {
1203		/* Flushing/putting all chains will cause the block to be
1204		 * deallocated when last chain is freed. However, if chain_list
1205		 * is empty, block has to be manually deallocated. After block
1206		 * reference counter reached 0, it is no longer possible to
1207		 * increment it or add new chains to block.
1208		 */
1209		bool free_block = list_empty(&block->chain_list);
1210
1211		mutex_unlock(&block->lock);
1212		if (tcf_block_shared(block))
1213			tcf_block_remove(block, block->net);
1214
1215		if (q)
1216			tcf_block_offload_unbind(block, q, ei);
1217
1218		if (free_block)
1219			tcf_block_destroy(block);
1220		else
1221			tcf_block_flush_all_chains(block, rtnl_held);
1222	} else if (q) {
1223		tcf_block_offload_unbind(block, q, ei);
1224	}
1225}
1226
1227static void tcf_block_refcnt_put(struct tcf_block *block, bool rtnl_held)
1228{
1229	__tcf_block_put(block, NULL, NULL, rtnl_held);
1230}
1231
1232/* Find tcf block.
1233 * Set q, parent, cl when appropriate.
1234 */
1235
1236static struct tcf_block *tcf_block_find(struct net *net, struct Qdisc **q,
1237					u32 *parent, unsigned long *cl,
1238					int ifindex, u32 block_index,
1239					struct netlink_ext_ack *extack)
1240{
1241	struct tcf_block *block;
1242	int err = 0;
1243
1244	ASSERT_RTNL();
1245
1246	err = __tcf_qdisc_find(net, q, parent, ifindex, true, extack);
1247	if (err)
1248		goto errout;
1249
1250	err = __tcf_qdisc_cl_find(*q, *parent, cl, ifindex, extack);
1251	if (err)
1252		goto errout_qdisc;
1253
1254	block = __tcf_block_find(net, *q, *cl, ifindex, block_index, extack);
1255	if (IS_ERR(block)) {
1256		err = PTR_ERR(block);
1257		goto errout_qdisc;
1258	}
1259
1260	return block;
1261
1262errout_qdisc:
1263	if (*q)
1264		qdisc_put(*q);
1265errout:
1266	*q = NULL;
1267	return ERR_PTR(err);
1268}
1269
1270static void tcf_block_release(struct Qdisc *q, struct tcf_block *block,
1271			      bool rtnl_held)
1272{
1273	if (!IS_ERR_OR_NULL(block))
1274		tcf_block_refcnt_put(block, rtnl_held);
1275
1276	if (q) {
1277		if (rtnl_held)
1278			qdisc_put(q);
1279		else
1280			qdisc_put_unlocked(q);
1281	}
1282}
1283
1284struct tcf_block_owner_item {
1285	struct list_head list;
1286	struct Qdisc *q;
1287	enum flow_block_binder_type binder_type;
1288};
1289
1290static void
1291tcf_block_owner_netif_keep_dst(struct tcf_block *block,
1292			       struct Qdisc *q,
1293			       enum flow_block_binder_type binder_type)
1294{
1295	if (block->keep_dst &&
1296	    binder_type != FLOW_BLOCK_BINDER_TYPE_CLSACT_INGRESS &&
1297	    binder_type != FLOW_BLOCK_BINDER_TYPE_CLSACT_EGRESS)
1298		netif_keep_dst(qdisc_dev(q));
1299}
1300
1301void tcf_block_netif_keep_dst(struct tcf_block *block)
1302{
1303	struct tcf_block_owner_item *item;
1304
1305	block->keep_dst = true;
1306	list_for_each_entry(item, &block->owner_list, list)
1307		tcf_block_owner_netif_keep_dst(block, item->q,
1308					       item->binder_type);
1309}
1310EXPORT_SYMBOL(tcf_block_netif_keep_dst);
1311
1312static int tcf_block_owner_add(struct tcf_block *block,
1313			       struct Qdisc *q,
1314			       enum flow_block_binder_type binder_type)
1315{
1316	struct tcf_block_owner_item *item;
1317
1318	item = kmalloc(sizeof(*item), GFP_KERNEL);
1319	if (!item)
1320		return -ENOMEM;
1321	item->q = q;
1322	item->binder_type = binder_type;
1323	list_add(&item->list, &block->owner_list);
1324	return 0;
1325}
1326
1327static void tcf_block_owner_del(struct tcf_block *block,
1328				struct Qdisc *q,
1329				enum flow_block_binder_type binder_type)
1330{
1331	struct tcf_block_owner_item *item;
1332
1333	list_for_each_entry(item, &block->owner_list, list) {
1334		if (item->q == q && item->binder_type == binder_type) {
1335			list_del(&item->list);
1336			kfree(item);
1337			return;
1338		}
1339	}
1340	WARN_ON(1);
1341}
1342
1343int tcf_block_get_ext(struct tcf_block **p_block, struct Qdisc *q,
1344		      struct tcf_block_ext_info *ei,
1345		      struct netlink_ext_ack *extack)
1346{
1347	struct net *net = qdisc_net(q);
1348	struct tcf_block *block = NULL;
1349	int err;
1350
1351	if (ei->block_index)
1352		/* block_index not 0 means the shared block is requested */
1353		block = tcf_block_refcnt_get(net, ei->block_index);
1354
1355	if (!block) {
1356		block = tcf_block_create(net, q, ei->block_index, extack);
1357		if (IS_ERR(block))
1358			return PTR_ERR(block);
1359		if (tcf_block_shared(block)) {
1360			err = tcf_block_insert(block, net, extack);
1361			if (err)
1362				goto err_block_insert;
1363		}
1364	}
1365
1366	err = tcf_block_owner_add(block, q, ei->binder_type);
1367	if (err)
1368		goto err_block_owner_add;
1369
1370	tcf_block_owner_netif_keep_dst(block, q, ei->binder_type);
1371
1372	err = tcf_chain0_head_change_cb_add(block, ei, extack);
1373	if (err)
1374		goto err_chain0_head_change_cb_add;
1375
1376	err = tcf_block_offload_bind(block, q, ei, extack);
1377	if (err)
1378		goto err_block_offload_bind;
1379
1380	*p_block = block;
1381	return 0;
1382
1383err_block_offload_bind:
1384	tcf_chain0_head_change_cb_del(block, ei);
1385err_chain0_head_change_cb_add:
1386	tcf_block_owner_del(block, q, ei->binder_type);
1387err_block_owner_add:
1388err_block_insert:
1389	tcf_block_refcnt_put(block, true);
1390	return err;
1391}
1392EXPORT_SYMBOL(tcf_block_get_ext);
1393
1394static void tcf_chain_head_change_dflt(struct tcf_proto *tp_head, void *priv)
1395{
1396	struct tcf_proto __rcu **p_filter_chain = priv;
1397
1398	rcu_assign_pointer(*p_filter_chain, tp_head);
1399}
1400
1401int tcf_block_get(struct tcf_block **p_block,
1402		  struct tcf_proto __rcu **p_filter_chain, struct Qdisc *q,
1403		  struct netlink_ext_ack *extack)
1404{
1405	struct tcf_block_ext_info ei = {
1406		.chain_head_change = tcf_chain_head_change_dflt,
1407		.chain_head_change_priv = p_filter_chain,
1408	};
1409
1410	WARN_ON(!p_filter_chain);
1411	return tcf_block_get_ext(p_block, q, &ei, extack);
1412}
1413EXPORT_SYMBOL(tcf_block_get);
1414
1415/* XXX: Standalone actions are not allowed to jump to any chain, and bound
1416 * actions should be all removed after flushing.
1417 */
1418void tcf_block_put_ext(struct tcf_block *block, struct Qdisc *q,
1419		       struct tcf_block_ext_info *ei)
1420{
1421	if (!block)
1422		return;
1423	tcf_chain0_head_change_cb_del(block, ei);
1424	tcf_block_owner_del(block, q, ei->binder_type);
1425
1426	__tcf_block_put(block, q, ei, true);
1427}
1428EXPORT_SYMBOL(tcf_block_put_ext);
1429
1430void tcf_block_put(struct tcf_block *block)
1431{
1432	struct tcf_block_ext_info ei = {0, };
1433
1434	if (!block)
1435		return;
1436	tcf_block_put_ext(block, block->q, &ei);
1437}
1438
1439EXPORT_SYMBOL(tcf_block_put);
1440
1441static int
1442tcf_block_playback_offloads(struct tcf_block *block, flow_setup_cb_t *cb,
1443			    void *cb_priv, bool add, bool offload_in_use,
1444			    struct netlink_ext_ack *extack)
1445{
1446	struct tcf_chain *chain, *chain_prev;
1447	struct tcf_proto *tp, *tp_prev;
1448	int err;
1449
1450	lockdep_assert_held(&block->cb_lock);
1451
1452	for (chain = __tcf_get_next_chain(block, NULL);
1453	     chain;
1454	     chain_prev = chain,
1455		     chain = __tcf_get_next_chain(block, chain),
1456		     tcf_chain_put(chain_prev)) {
1457		for (tp = __tcf_get_next_proto(chain, NULL); tp;
1458		     tp_prev = tp,
1459			     tp = __tcf_get_next_proto(chain, tp),
1460			     tcf_proto_put(tp_prev, true, NULL)) {
1461			if (tp->ops->reoffload) {
1462				err = tp->ops->reoffload(tp, add, cb, cb_priv,
1463							 extack);
1464				if (err && add)
1465					goto err_playback_remove;
1466			} else if (add && offload_in_use) {
1467				err = -EOPNOTSUPP;
1468				NL_SET_ERR_MSG(extack, "Filter HW offload failed - classifier without re-offloading support");
1469				goto err_playback_remove;
1470			}
1471		}
1472	}
1473
1474	return 0;
1475
1476err_playback_remove:
1477	tcf_proto_put(tp, true, NULL);
1478	tcf_chain_put(chain);
1479	tcf_block_playback_offloads(block, cb, cb_priv, false, offload_in_use,
1480				    extack);
1481	return err;
1482}
1483
1484static int tcf_block_bind(struct tcf_block *block,
1485			  struct flow_block_offload *bo)
1486{
1487	struct flow_block_cb *block_cb, *next;
1488	int err, i = 0;
1489
1490	lockdep_assert_held(&block->cb_lock);
1491
1492	list_for_each_entry(block_cb, &bo->cb_list, list) {
1493		err = tcf_block_playback_offloads(block, block_cb->cb,
1494						  block_cb->cb_priv, true,
1495						  tcf_block_offload_in_use(block),
1496						  bo->extack);
1497		if (err)
1498			goto err_unroll;
1499		if (!bo->unlocked_driver_cb)
1500			block->lockeddevcnt++;
1501
1502		i++;
1503	}
1504	list_splice(&bo->cb_list, &block->flow_block.cb_list);
1505
1506	return 0;
1507
1508err_unroll:
1509	list_for_each_entry_safe(block_cb, next, &bo->cb_list, list) {
1510		if (i-- > 0) {
1511			list_del(&block_cb->list);
1512			tcf_block_playback_offloads(block, block_cb->cb,
1513						    block_cb->cb_priv, false,
1514						    tcf_block_offload_in_use(block),
1515						    NULL);
1516			if (!bo->unlocked_driver_cb)
1517				block->lockeddevcnt--;
1518		}
1519		flow_block_cb_free(block_cb);
1520	}
1521
1522	return err;
1523}
1524
1525static void tcf_block_unbind(struct tcf_block *block,
1526			     struct flow_block_offload *bo)
1527{
1528	struct flow_block_cb *block_cb, *next;
1529
1530	lockdep_assert_held(&block->cb_lock);
1531
1532	list_for_each_entry_safe(block_cb, next, &bo->cb_list, list) {
1533		tcf_block_playback_offloads(block, block_cb->cb,
1534					    block_cb->cb_priv, false,
1535					    tcf_block_offload_in_use(block),
1536					    NULL);
1537		list_del(&block_cb->list);
1538		flow_block_cb_free(block_cb);
1539		if (!bo->unlocked_driver_cb)
1540			block->lockeddevcnt--;
1541	}
1542}
1543
1544static int tcf_block_setup(struct tcf_block *block,
1545			   struct flow_block_offload *bo)
1546{
1547	int err;
1548
1549	switch (bo->command) {
1550	case FLOW_BLOCK_BIND:
1551		err = tcf_block_bind(block, bo);
1552		break;
1553	case FLOW_BLOCK_UNBIND:
1554		err = 0;
1555		tcf_block_unbind(block, bo);
1556		break;
1557	default:
1558		WARN_ON_ONCE(1);
1559		err = -EOPNOTSUPP;
1560	}
1561
1562	return err;
1563}
1564
1565/* Main classifier routine: scans classifier chain attached
1566 * to this qdisc, (optionally) tests for protocol and asks
1567 * specific classifiers.
1568 */
1569int tcf_classify(struct sk_buff *skb, const struct tcf_proto *tp,
1570		 struct tcf_result *res, bool compat_mode)
 
 
 
 
1571{
1572#ifdef CONFIG_NET_CLS_ACT
1573	const int max_reclassify_loop = 4;
1574	const struct tcf_proto *orig_tp = tp;
1575	const struct tcf_proto *first_tp;
1576	int limit = 0;
1577
1578reclassify:
1579#endif
1580	for (; tp; tp = rcu_dereference_bh(tp->next)) {
1581		__be16 protocol = tc_skb_protocol(skb);
1582		int err;
1583
1584		if (tp->protocol != protocol &&
1585		    tp->protocol != htons(ETH_P_ALL))
1586			continue;
1587
1588		err = tp->classify(skb, tp, res);
1589#ifdef CONFIG_NET_CLS_ACT
1590		if (unlikely(err == TC_ACT_RECLASSIFY && !compat_mode)) {
1591			first_tp = orig_tp;
 
1592			goto reset;
1593		} else if (unlikely(TC_ACT_EXT_CMP(err, TC_ACT_GOTO_CHAIN))) {
1594			first_tp = res->goto_tp;
1595
1596#if IS_ENABLED(CONFIG_NET_TC_SKB_EXT)
1597			{
1598				struct tc_skb_ext *ext;
1599
1600				ext = skb_ext_add(skb, TC_SKB_EXT);
1601				if (WARN_ON_ONCE(!ext))
1602					return TC_ACT_SHOT;
1603
1604				ext->chain = err & TC_ACT_EXT_VAL_MASK;
1605			}
1606#endif
1607			goto reset;
1608		}
1609#endif
1610		if (err >= 0)
1611			return err;
1612	}
1613
1614	return TC_ACT_UNSPEC; /* signal: continue lookup */
1615#ifdef CONFIG_NET_CLS_ACT
1616reset:
1617	if (unlikely(limit++ >= max_reclassify_loop)) {
1618		net_notice_ratelimited("%u: reclassify loop, rule prio %u, protocol %02x\n",
1619				       tp->chain->block->index,
1620				       tp->prio & 0xffff,
1621				       ntohs(tp->protocol));
1622		return TC_ACT_SHOT;
1623	}
1624
1625	tp = first_tp;
1626	goto reclassify;
1627#endif
1628}
 
 
 
 
 
 
 
 
 
1629EXPORT_SYMBOL(tcf_classify);
1630
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1631struct tcf_chain_info {
1632	struct tcf_proto __rcu **pprev;
1633	struct tcf_proto __rcu *next;
1634};
1635
1636static struct tcf_proto *tcf_chain_tp_prev(struct tcf_chain *chain,
1637					   struct tcf_chain_info *chain_info)
1638{
1639	return tcf_chain_dereference(*chain_info->pprev, chain);
1640}
1641
1642static int tcf_chain_tp_insert(struct tcf_chain *chain,
1643			       struct tcf_chain_info *chain_info,
1644			       struct tcf_proto *tp)
1645{
1646	if (chain->flushing)
1647		return -EAGAIN;
1648
1649	if (*chain_info->pprev == chain->filter_chain)
1650		tcf_chain0_head_change(chain, tp);
1651	tcf_proto_get(tp);
1652	RCU_INIT_POINTER(tp->next, tcf_chain_tp_prev(chain, chain_info));
1653	rcu_assign_pointer(*chain_info->pprev, tp);
1654
1655	return 0;
1656}
1657
1658static void tcf_chain_tp_remove(struct tcf_chain *chain,
1659				struct tcf_chain_info *chain_info,
1660				struct tcf_proto *tp)
1661{
1662	struct tcf_proto *next = tcf_chain_dereference(chain_info->next, chain);
1663
1664	tcf_proto_mark_delete(tp);
1665	if (tp == chain->filter_chain)
1666		tcf_chain0_head_change(chain, next);
1667	RCU_INIT_POINTER(*chain_info->pprev, next);
1668}
1669
1670static struct tcf_proto *tcf_chain_tp_find(struct tcf_chain *chain,
1671					   struct tcf_chain_info *chain_info,
1672					   u32 protocol, u32 prio,
1673					   bool prio_allocate);
1674
1675/* Try to insert new proto.
1676 * If proto with specified priority already exists, free new proto
1677 * and return existing one.
1678 */
1679
1680static struct tcf_proto *tcf_chain_tp_insert_unique(struct tcf_chain *chain,
1681						    struct tcf_proto *tp_new,
1682						    u32 protocol, u32 prio,
1683						    bool rtnl_held)
1684{
1685	struct tcf_chain_info chain_info;
1686	struct tcf_proto *tp;
1687	int err = 0;
1688
1689	mutex_lock(&chain->filter_chain_lock);
1690
1691	if (tcf_proto_exists_destroying(chain, tp_new)) {
1692		mutex_unlock(&chain->filter_chain_lock);
1693		tcf_proto_destroy(tp_new, rtnl_held, false, NULL);
1694		return ERR_PTR(-EAGAIN);
1695	}
1696
1697	tp = tcf_chain_tp_find(chain, &chain_info,
1698			       protocol, prio, false);
1699	if (!tp)
1700		err = tcf_chain_tp_insert(chain, &chain_info, tp_new);
1701	mutex_unlock(&chain->filter_chain_lock);
1702
1703	if (tp) {
1704		tcf_proto_destroy(tp_new, rtnl_held, false, NULL);
1705		tp_new = tp;
1706	} else if (err) {
1707		tcf_proto_destroy(tp_new, rtnl_held, false, NULL);
1708		tp_new = ERR_PTR(err);
1709	}
1710
1711	return tp_new;
1712}
1713
1714static void tcf_chain_tp_delete_empty(struct tcf_chain *chain,
1715				      struct tcf_proto *tp, bool rtnl_held,
1716				      struct netlink_ext_ack *extack)
1717{
1718	struct tcf_chain_info chain_info;
1719	struct tcf_proto *tp_iter;
1720	struct tcf_proto **pprev;
1721	struct tcf_proto *next;
1722
1723	mutex_lock(&chain->filter_chain_lock);
1724
1725	/* Atomically find and remove tp from chain. */
1726	for (pprev = &chain->filter_chain;
1727	     (tp_iter = tcf_chain_dereference(*pprev, chain));
1728	     pprev = &tp_iter->next) {
1729		if (tp_iter == tp) {
1730			chain_info.pprev = pprev;
1731			chain_info.next = tp_iter->next;
1732			WARN_ON(tp_iter->deleting);
1733			break;
1734		}
1735	}
1736	/* Verify that tp still exists and no new filters were inserted
1737	 * concurrently.
1738	 * Mark tp for deletion if it is empty.
1739	 */
1740	if (!tp_iter || !tcf_proto_check_delete(tp, rtnl_held)) {
1741		mutex_unlock(&chain->filter_chain_lock);
1742		return;
1743	}
1744
1745	tcf_proto_signal_destroying(chain, tp);
1746	next = tcf_chain_dereference(chain_info.next, chain);
1747	if (tp == chain->filter_chain)
1748		tcf_chain0_head_change(chain, next);
1749	RCU_INIT_POINTER(*chain_info.pprev, next);
1750	mutex_unlock(&chain->filter_chain_lock);
1751
1752	tcf_proto_put(tp, rtnl_held, extack);
1753}
1754
1755static struct tcf_proto *tcf_chain_tp_find(struct tcf_chain *chain,
1756					   struct tcf_chain_info *chain_info,
1757					   u32 protocol, u32 prio,
1758					   bool prio_allocate)
1759{
1760	struct tcf_proto **pprev;
1761	struct tcf_proto *tp;
1762
1763	/* Check the chain for existence of proto-tcf with this priority */
1764	for (pprev = &chain->filter_chain;
1765	     (tp = tcf_chain_dereference(*pprev, chain));
1766	     pprev = &tp->next) {
1767		if (tp->prio >= prio) {
1768			if (tp->prio == prio) {
1769				if (prio_allocate ||
1770				    (tp->protocol != protocol && protocol))
1771					return ERR_PTR(-EINVAL);
1772			} else {
1773				tp = NULL;
1774			}
1775			break;
1776		}
1777	}
1778	chain_info->pprev = pprev;
1779	if (tp) {
1780		chain_info->next = tp->next;
1781		tcf_proto_get(tp);
1782	} else {
1783		chain_info->next = NULL;
1784	}
1785	return tp;
1786}
1787
1788static int tcf_fill_node(struct net *net, struct sk_buff *skb,
1789			 struct tcf_proto *tp, struct tcf_block *block,
1790			 struct Qdisc *q, u32 parent, void *fh,
1791			 u32 portid, u32 seq, u16 flags, int event,
1792			 bool rtnl_held)
1793{
1794	struct tcmsg *tcm;
1795	struct nlmsghdr  *nlh;
1796	unsigned char *b = skb_tail_pointer(skb);
1797
1798	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*tcm), flags);
1799	if (!nlh)
1800		goto out_nlmsg_trim;
1801	tcm = nlmsg_data(nlh);
1802	tcm->tcm_family = AF_UNSPEC;
1803	tcm->tcm__pad1 = 0;
1804	tcm->tcm__pad2 = 0;
1805	if (q) {
1806		tcm->tcm_ifindex = qdisc_dev(q)->ifindex;
1807		tcm->tcm_parent = parent;
1808	} else {
1809		tcm->tcm_ifindex = TCM_IFINDEX_MAGIC_BLOCK;
1810		tcm->tcm_block_index = block->index;
1811	}
1812	tcm->tcm_info = TC_H_MAKE(tp->prio, tp->protocol);
1813	if (nla_put_string(skb, TCA_KIND, tp->ops->kind))
1814		goto nla_put_failure;
1815	if (nla_put_u32(skb, TCA_CHAIN, tp->chain->index))
1816		goto nla_put_failure;
1817	if (!fh) {
1818		tcm->tcm_handle = 0;
 
 
 
 
 
 
 
 
1819	} else {
1820		if (tp->ops->dump &&
1821		    tp->ops->dump(net, tp, fh, skb, tcm, rtnl_held) < 0)
1822			goto nla_put_failure;
1823	}
1824	nlh->nlmsg_len = skb_tail_pointer(skb) - b;
1825	return skb->len;
1826
1827out_nlmsg_trim:
1828nla_put_failure:
 
1829	nlmsg_trim(skb, b);
1830	return -1;
1831}
1832
1833static int tfilter_notify(struct net *net, struct sk_buff *oskb,
1834			  struct nlmsghdr *n, struct tcf_proto *tp,
1835			  struct tcf_block *block, struct Qdisc *q,
1836			  u32 parent, void *fh, int event, bool unicast,
1837			  bool rtnl_held)
1838{
1839	struct sk_buff *skb;
1840	u32 portid = oskb ? NETLINK_CB(oskb).portid : 0;
1841	int err = 0;
1842
1843	skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
1844	if (!skb)
1845		return -ENOBUFS;
1846
1847	if (tcf_fill_node(net, skb, tp, block, q, parent, fh, portid,
1848			  n->nlmsg_seq, n->nlmsg_flags, event,
1849			  rtnl_held) <= 0) {
1850		kfree_skb(skb);
1851		return -EINVAL;
1852	}
1853
1854	if (unicast)
1855		err = netlink_unicast(net->rtnl, skb, portid, MSG_DONTWAIT);
1856	else
1857		err = rtnetlink_send(skb, net, portid, RTNLGRP_TC,
1858				     n->nlmsg_flags & NLM_F_ECHO);
1859
1860	if (err > 0)
1861		err = 0;
1862	return err;
1863}
1864
1865static int tfilter_del_notify(struct net *net, struct sk_buff *oskb,
1866			      struct nlmsghdr *n, struct tcf_proto *tp,
1867			      struct tcf_block *block, struct Qdisc *q,
1868			      u32 parent, void *fh, bool unicast, bool *last,
1869			      bool rtnl_held, struct netlink_ext_ack *extack)
1870{
1871	struct sk_buff *skb;
1872	u32 portid = oskb ? NETLINK_CB(oskb).portid : 0;
1873	int err;
1874
1875	skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
1876	if (!skb)
1877		return -ENOBUFS;
1878
1879	if (tcf_fill_node(net, skb, tp, block, q, parent, fh, portid,
1880			  n->nlmsg_seq, n->nlmsg_flags, RTM_DELTFILTER,
1881			  rtnl_held) <= 0) {
1882		NL_SET_ERR_MSG(extack, "Failed to build del event notification");
1883		kfree_skb(skb);
1884		return -EINVAL;
1885	}
1886
1887	err = tp->ops->delete(tp, fh, last, rtnl_held, extack);
1888	if (err) {
1889		kfree_skb(skb);
1890		return err;
1891	}
1892
1893	if (unicast)
1894		err = netlink_unicast(net->rtnl, skb, portid, MSG_DONTWAIT);
1895	else
1896		err = rtnetlink_send(skb, net, portid, RTNLGRP_TC,
1897				     n->nlmsg_flags & NLM_F_ECHO);
1898	if (err < 0)
1899		NL_SET_ERR_MSG(extack, "Failed to send filter delete notification");
1900
1901	if (err > 0)
1902		err = 0;
1903	return err;
1904}
1905
1906static void tfilter_notify_chain(struct net *net, struct sk_buff *oskb,
1907				 struct tcf_block *block, struct Qdisc *q,
1908				 u32 parent, struct nlmsghdr *n,
1909				 struct tcf_chain *chain, int event,
1910				 bool rtnl_held)
1911{
1912	struct tcf_proto *tp;
1913
1914	for (tp = tcf_get_next_proto(chain, NULL, rtnl_held);
1915	     tp; tp = tcf_get_next_proto(chain, tp, rtnl_held))
1916		tfilter_notify(net, oskb, n, tp, block,
1917			       q, parent, NULL, event, false, rtnl_held);
1918}
1919
1920static void tfilter_put(struct tcf_proto *tp, void *fh)
1921{
1922	if (tp->ops->put && fh)
1923		tp->ops->put(tp, fh);
1924}
1925
1926static int tc_new_tfilter(struct sk_buff *skb, struct nlmsghdr *n,
1927			  struct netlink_ext_ack *extack)
1928{
1929	struct net *net = sock_net(skb->sk);
1930	struct nlattr *tca[TCA_MAX + 1];
1931	char name[IFNAMSIZ];
1932	struct tcmsg *t;
1933	u32 protocol;
1934	u32 prio;
1935	bool prio_allocate;
1936	u32 parent;
1937	u32 chain_index;
1938	struct Qdisc *q = NULL;
1939	struct tcf_chain_info chain_info;
1940	struct tcf_chain *chain = NULL;
1941	struct tcf_block *block;
1942	struct tcf_proto *tp;
1943	unsigned long cl;
1944	void *fh;
1945	int err;
1946	int tp_created;
1947	bool rtnl_held = false;
1948
1949	if (!netlink_ns_capable(skb, net->user_ns, CAP_NET_ADMIN))
1950		return -EPERM;
1951
1952replay:
1953	tp_created = 0;
1954
1955	err = nlmsg_parse_deprecated(n, sizeof(*t), tca, TCA_MAX,
1956				     rtm_tca_policy, extack);
1957	if (err < 0)
1958		return err;
1959
1960	t = nlmsg_data(n);
1961	protocol = TC_H_MIN(t->tcm_info);
1962	prio = TC_H_MAJ(t->tcm_info);
1963	prio_allocate = false;
1964	parent = t->tcm_parent;
1965	tp = NULL;
1966	cl = 0;
1967	block = NULL;
1968
1969	if (prio == 0) {
1970		/* If no priority is provided by the user,
1971		 * we allocate one.
1972		 */
1973		if (n->nlmsg_flags & NLM_F_CREATE) {
1974			prio = TC_H_MAKE(0x80000000U, 0U);
1975			prio_allocate = true;
1976		} else {
1977			NL_SET_ERR_MSG(extack, "Invalid filter command with priority of zero");
1978			return -ENOENT;
1979		}
1980	}
1981
1982	/* Find head of filter chain. */
1983
1984	err = __tcf_qdisc_find(net, &q, &parent, t->tcm_ifindex, false, extack);
1985	if (err)
1986		return err;
1987
1988	if (tcf_proto_check_kind(tca[TCA_KIND], name)) {
1989		NL_SET_ERR_MSG(extack, "Specified TC filter name too long");
1990		err = -EINVAL;
1991		goto errout;
1992	}
1993
1994	/* Take rtnl mutex if rtnl_held was set to true on previous iteration,
1995	 * block is shared (no qdisc found), qdisc is not unlocked, classifier
1996	 * type is not specified, classifier is not unlocked.
1997	 */
1998	if (rtnl_held ||
1999	    (q && !(q->ops->cl_ops->flags & QDISC_CLASS_OPS_DOIT_UNLOCKED)) ||
2000	    !tcf_proto_is_unlocked(name)) {
2001		rtnl_held = true;
2002		rtnl_lock();
2003	}
2004
2005	err = __tcf_qdisc_cl_find(q, parent, &cl, t->tcm_ifindex, extack);
2006	if (err)
2007		goto errout;
2008
2009	block = __tcf_block_find(net, q, cl, t->tcm_ifindex, t->tcm_block_index,
2010				 extack);
2011	if (IS_ERR(block)) {
2012		err = PTR_ERR(block);
2013		goto errout;
2014	}
 
2015
2016	chain_index = tca[TCA_CHAIN] ? nla_get_u32(tca[TCA_CHAIN]) : 0;
2017	if (chain_index > TC_ACT_EXT_VAL_MASK) {
2018		NL_SET_ERR_MSG(extack, "Specified chain index exceeds upper limit");
2019		err = -EINVAL;
2020		goto errout;
2021	}
2022	chain = tcf_chain_get(block, chain_index, true);
2023	if (!chain) {
2024		NL_SET_ERR_MSG(extack, "Cannot create specified filter chain");
2025		err = -ENOMEM;
2026		goto errout;
2027	}
2028
2029	mutex_lock(&chain->filter_chain_lock);
2030	tp = tcf_chain_tp_find(chain, &chain_info, protocol,
2031			       prio, prio_allocate);
2032	if (IS_ERR(tp)) {
2033		NL_SET_ERR_MSG(extack, "Filter with specified priority/protocol not found");
2034		err = PTR_ERR(tp);
2035		goto errout_locked;
2036	}
2037
2038	if (tp == NULL) {
2039		struct tcf_proto *tp_new = NULL;
2040
2041		if (chain->flushing) {
2042			err = -EAGAIN;
2043			goto errout_locked;
2044		}
2045
2046		/* Proto-tcf does not exist, create new one */
2047
2048		if (tca[TCA_KIND] == NULL || !protocol) {
2049			NL_SET_ERR_MSG(extack, "Filter kind and protocol must be specified");
2050			err = -EINVAL;
2051			goto errout_locked;
2052		}
2053
2054		if (!(n->nlmsg_flags & NLM_F_CREATE)) {
2055			NL_SET_ERR_MSG(extack, "Need both RTM_NEWTFILTER and NLM_F_CREATE to create a new filter");
2056			err = -ENOENT;
2057			goto errout_locked;
2058		}
2059
2060		if (prio_allocate)
2061			prio = tcf_auto_prio(tcf_chain_tp_prev(chain,
2062							       &chain_info));
2063
2064		mutex_unlock(&chain->filter_chain_lock);
2065		tp_new = tcf_proto_create(nla_data(tca[TCA_KIND]),
2066					  protocol, prio, chain, rtnl_held,
2067					  extack);
2068		if (IS_ERR(tp_new)) {
2069			err = PTR_ERR(tp_new);
2070			goto errout_tp;
2071		}
2072
2073		tp_created = 1;
2074		tp = tcf_chain_tp_insert_unique(chain, tp_new, protocol, prio,
2075						rtnl_held);
2076		if (IS_ERR(tp)) {
2077			err = PTR_ERR(tp);
2078			goto errout_tp;
2079		}
2080	} else {
2081		mutex_unlock(&chain->filter_chain_lock);
2082	}
2083
2084	if (tca[TCA_KIND] && nla_strcmp(tca[TCA_KIND], tp->ops->kind)) {
2085		NL_SET_ERR_MSG(extack, "Specified filter kind does not match existing one");
2086		err = -EINVAL;
2087		goto errout;
2088	}
2089
2090	fh = tp->ops->get(tp, t->tcm_handle);
2091
2092	if (!fh) {
2093		if (!(n->nlmsg_flags & NLM_F_CREATE)) {
2094			NL_SET_ERR_MSG(extack, "Need both RTM_NEWTFILTER and NLM_F_CREATE to create a new filter");
2095			err = -ENOENT;
2096			goto errout;
2097		}
2098	} else if (n->nlmsg_flags & NLM_F_EXCL) {
2099		tfilter_put(tp, fh);
2100		NL_SET_ERR_MSG(extack, "Filter already exists");
2101		err = -EEXIST;
2102		goto errout;
2103	}
2104
2105	if (chain->tmplt_ops && chain->tmplt_ops != tp->ops) {
2106		NL_SET_ERR_MSG(extack, "Chain template is set to a different filter kind");
2107		err = -EINVAL;
2108		goto errout;
2109	}
2110
2111	err = tp->ops->change(net, skb, tp, cl, t->tcm_handle, tca, &fh,
2112			      n->nlmsg_flags & NLM_F_CREATE ? TCA_ACT_NOREPLACE : TCA_ACT_REPLACE,
2113			      rtnl_held, extack);
2114	if (err == 0) {
2115		tfilter_notify(net, skb, n, tp, block, q, parent, fh,
2116			       RTM_NEWTFILTER, false, rtnl_held);
2117		tfilter_put(tp, fh);
2118		/* q pointer is NULL for shared blocks */
2119		if (q)
2120			q->flags &= ~TCQ_F_CAN_BYPASS;
2121	}
2122
2123errout:
2124	if (err && tp_created)
2125		tcf_chain_tp_delete_empty(chain, tp, rtnl_held, NULL);
2126errout_tp:
2127	if (chain) {
2128		if (tp && !IS_ERR(tp))
2129			tcf_proto_put(tp, rtnl_held, NULL);
2130		if (!tp_created)
2131			tcf_chain_put(chain);
2132	}
2133	tcf_block_release(q, block, rtnl_held);
2134
2135	if (rtnl_held)
2136		rtnl_unlock();
2137
2138	if (err == -EAGAIN) {
2139		/* Take rtnl lock in case EAGAIN is caused by concurrent flush
2140		 * of target chain.
2141		 */
2142		rtnl_held = true;
2143		/* Replay the request. */
2144		goto replay;
2145	}
2146	return err;
2147
2148errout_locked:
2149	mutex_unlock(&chain->filter_chain_lock);
2150	goto errout;
2151}
2152
2153static int tc_del_tfilter(struct sk_buff *skb, struct nlmsghdr *n,
2154			  struct netlink_ext_ack *extack)
2155{
2156	struct net *net = sock_net(skb->sk);
2157	struct nlattr *tca[TCA_MAX + 1];
2158	char name[IFNAMSIZ];
2159	struct tcmsg *t;
2160	u32 protocol;
2161	u32 prio;
2162	u32 parent;
2163	u32 chain_index;
2164	struct Qdisc *q = NULL;
2165	struct tcf_chain_info chain_info;
2166	struct tcf_chain *chain = NULL;
2167	struct tcf_block *block = NULL;
2168	struct tcf_proto *tp = NULL;
2169	unsigned long cl = 0;
2170	void *fh = NULL;
2171	int err;
2172	bool rtnl_held = false;
2173
2174	if (!netlink_ns_capable(skb, net->user_ns, CAP_NET_ADMIN))
2175		return -EPERM;
2176
2177	err = nlmsg_parse_deprecated(n, sizeof(*t), tca, TCA_MAX,
2178				     rtm_tca_policy, extack);
2179	if (err < 0)
2180		return err;
2181
2182	t = nlmsg_data(n);
2183	protocol = TC_H_MIN(t->tcm_info);
2184	prio = TC_H_MAJ(t->tcm_info);
2185	parent = t->tcm_parent;
2186
2187	if (prio == 0 && (protocol || t->tcm_handle || tca[TCA_KIND])) {
2188		NL_SET_ERR_MSG(extack, "Cannot flush filters with protocol, handle or kind set");
2189		return -ENOENT;
2190	}
2191
2192	/* Find head of filter chain. */
2193
2194	err = __tcf_qdisc_find(net, &q, &parent, t->tcm_ifindex, false, extack);
2195	if (err)
2196		return err;
2197
2198	if (tcf_proto_check_kind(tca[TCA_KIND], name)) {
2199		NL_SET_ERR_MSG(extack, "Specified TC filter name too long");
2200		err = -EINVAL;
2201		goto errout;
2202	}
2203	/* Take rtnl mutex if flushing whole chain, block is shared (no qdisc
2204	 * found), qdisc is not unlocked, classifier type is not specified,
2205	 * classifier is not unlocked.
2206	 */
2207	if (!prio ||
2208	    (q && !(q->ops->cl_ops->flags & QDISC_CLASS_OPS_DOIT_UNLOCKED)) ||
2209	    !tcf_proto_is_unlocked(name)) {
2210		rtnl_held = true;
2211		rtnl_lock();
2212	}
2213
2214	err = __tcf_qdisc_cl_find(q, parent, &cl, t->tcm_ifindex, extack);
2215	if (err)
2216		goto errout;
2217
2218	block = __tcf_block_find(net, q, cl, t->tcm_ifindex, t->tcm_block_index,
2219				 extack);
2220	if (IS_ERR(block)) {
2221		err = PTR_ERR(block);
2222		goto errout;
2223	}
2224
2225	chain_index = tca[TCA_CHAIN] ? nla_get_u32(tca[TCA_CHAIN]) : 0;
2226	if (chain_index > TC_ACT_EXT_VAL_MASK) {
2227		NL_SET_ERR_MSG(extack, "Specified chain index exceeds upper limit");
2228		err = -EINVAL;
2229		goto errout;
2230	}
2231	chain = tcf_chain_get(block, chain_index, false);
2232	if (!chain) {
2233		/* User requested flush on non-existent chain. Nothing to do,
2234		 * so just return success.
2235		 */
2236		if (prio == 0) {
2237			err = 0;
2238			goto errout;
2239		}
2240		NL_SET_ERR_MSG(extack, "Cannot find specified filter chain");
2241		err = -ENOENT;
2242		goto errout;
2243	}
2244
2245	if (prio == 0) {
2246		tfilter_notify_chain(net, skb, block, q, parent, n,
2247				     chain, RTM_DELTFILTER, rtnl_held);
2248		tcf_chain_flush(chain, rtnl_held);
2249		err = 0;
2250		goto errout;
2251	}
2252
2253	mutex_lock(&chain->filter_chain_lock);
2254	tp = tcf_chain_tp_find(chain, &chain_info, protocol,
2255			       prio, false);
2256	if (!tp || IS_ERR(tp)) {
2257		NL_SET_ERR_MSG(extack, "Filter with specified priority/protocol not found");
2258		err = tp ? PTR_ERR(tp) : -ENOENT;
2259		goto errout_locked;
2260	} else if (tca[TCA_KIND] && nla_strcmp(tca[TCA_KIND], tp->ops->kind)) {
2261		NL_SET_ERR_MSG(extack, "Specified filter kind does not match existing one");
2262		err = -EINVAL;
2263		goto errout_locked;
2264	} else if (t->tcm_handle == 0) {
2265		tcf_proto_signal_destroying(chain, tp);
2266		tcf_chain_tp_remove(chain, &chain_info, tp);
2267		mutex_unlock(&chain->filter_chain_lock);
2268
2269		tcf_proto_put(tp, rtnl_held, NULL);
2270		tfilter_notify(net, skb, n, tp, block, q, parent, fh,
2271			       RTM_DELTFILTER, false, rtnl_held);
2272		err = 0;
2273		goto errout;
2274	}
2275	mutex_unlock(&chain->filter_chain_lock);
2276
2277	fh = tp->ops->get(tp, t->tcm_handle);
2278
2279	if (!fh) {
2280		NL_SET_ERR_MSG(extack, "Specified filter handle not found");
2281		err = -ENOENT;
2282	} else {
2283		bool last;
2284
2285		err = tfilter_del_notify(net, skb, n, tp, block,
2286					 q, parent, fh, false, &last,
2287					 rtnl_held, extack);
2288
2289		if (err)
2290			goto errout;
2291		if (last)
2292			tcf_chain_tp_delete_empty(chain, tp, rtnl_held, extack);
2293	}
2294
2295errout:
2296	if (chain) {
2297		if (tp && !IS_ERR(tp))
2298			tcf_proto_put(tp, rtnl_held, NULL);
2299		tcf_chain_put(chain);
2300	}
2301	tcf_block_release(q, block, rtnl_held);
2302
2303	if (rtnl_held)
2304		rtnl_unlock();
2305
2306	return err;
2307
2308errout_locked:
2309	mutex_unlock(&chain->filter_chain_lock);
2310	goto errout;
2311}
2312
2313static int tc_get_tfilter(struct sk_buff *skb, struct nlmsghdr *n,
2314			  struct netlink_ext_ack *extack)
2315{
2316	struct net *net = sock_net(skb->sk);
2317	struct nlattr *tca[TCA_MAX + 1];
2318	char name[IFNAMSIZ];
2319	struct tcmsg *t;
2320	u32 protocol;
2321	u32 prio;
2322	u32 parent;
2323	u32 chain_index;
2324	struct Qdisc *q = NULL;
2325	struct tcf_chain_info chain_info;
2326	struct tcf_chain *chain = NULL;
2327	struct tcf_block *block = NULL;
2328	struct tcf_proto *tp = NULL;
2329	unsigned long cl = 0;
2330	void *fh = NULL;
2331	int err;
2332	bool rtnl_held = false;
2333
2334	err = nlmsg_parse_deprecated(n, sizeof(*t), tca, TCA_MAX,
2335				     rtm_tca_policy, extack);
2336	if (err < 0)
2337		return err;
2338
2339	t = nlmsg_data(n);
2340	protocol = TC_H_MIN(t->tcm_info);
2341	prio = TC_H_MAJ(t->tcm_info);
2342	parent = t->tcm_parent;
2343
2344	if (prio == 0) {
2345		NL_SET_ERR_MSG(extack, "Invalid filter command with priority of zero");
2346		return -ENOENT;
2347	}
2348
2349	/* Find head of filter chain. */
2350
2351	err = __tcf_qdisc_find(net, &q, &parent, t->tcm_ifindex, false, extack);
2352	if (err)
2353		return err;
2354
2355	if (tcf_proto_check_kind(tca[TCA_KIND], name)) {
2356		NL_SET_ERR_MSG(extack, "Specified TC filter name too long");
2357		err = -EINVAL;
2358		goto errout;
2359	}
2360	/* Take rtnl mutex if block is shared (no qdisc found), qdisc is not
2361	 * unlocked, classifier type is not specified, classifier is not
2362	 * unlocked.
2363	 */
2364	if ((q && !(q->ops->cl_ops->flags & QDISC_CLASS_OPS_DOIT_UNLOCKED)) ||
2365	    !tcf_proto_is_unlocked(name)) {
2366		rtnl_held = true;
2367		rtnl_lock();
2368	}
2369
2370	err = __tcf_qdisc_cl_find(q, parent, &cl, t->tcm_ifindex, extack);
2371	if (err)
2372		goto errout;
2373
2374	block = __tcf_block_find(net, q, cl, t->tcm_ifindex, t->tcm_block_index,
2375				 extack);
2376	if (IS_ERR(block)) {
2377		err = PTR_ERR(block);
2378		goto errout;
2379	}
2380
2381	chain_index = tca[TCA_CHAIN] ? nla_get_u32(tca[TCA_CHAIN]) : 0;
2382	if (chain_index > TC_ACT_EXT_VAL_MASK) {
2383		NL_SET_ERR_MSG(extack, "Specified chain index exceeds upper limit");
2384		err = -EINVAL;
2385		goto errout;
2386	}
2387	chain = tcf_chain_get(block, chain_index, false);
2388	if (!chain) {
2389		NL_SET_ERR_MSG(extack, "Cannot find specified filter chain");
2390		err = -EINVAL;
2391		goto errout;
2392	}
2393
2394	mutex_lock(&chain->filter_chain_lock);
2395	tp = tcf_chain_tp_find(chain, &chain_info, protocol,
2396			       prio, false);
2397	mutex_unlock(&chain->filter_chain_lock);
2398	if (!tp || IS_ERR(tp)) {
2399		NL_SET_ERR_MSG(extack, "Filter with specified priority/protocol not found");
2400		err = tp ? PTR_ERR(tp) : -ENOENT;
2401		goto errout;
2402	} else if (tca[TCA_KIND] && nla_strcmp(tca[TCA_KIND], tp->ops->kind)) {
2403		NL_SET_ERR_MSG(extack, "Specified filter kind does not match existing one");
2404		err = -EINVAL;
2405		goto errout;
2406	}
2407
2408	fh = tp->ops->get(tp, t->tcm_handle);
2409
2410	if (!fh) {
2411		NL_SET_ERR_MSG(extack, "Specified filter handle not found");
2412		err = -ENOENT;
2413	} else {
2414		err = tfilter_notify(net, skb, n, tp, block, q, parent,
2415				     fh, RTM_NEWTFILTER, true, rtnl_held);
2416		if (err < 0)
2417			NL_SET_ERR_MSG(extack, "Failed to send filter notify message");
2418	}
2419
2420	tfilter_put(tp, fh);
2421errout:
2422	if (chain) {
2423		if (tp && !IS_ERR(tp))
2424			tcf_proto_put(tp, rtnl_held, NULL);
2425		tcf_chain_put(chain);
2426	}
2427	tcf_block_release(q, block, rtnl_held);
2428
2429	if (rtnl_held)
2430		rtnl_unlock();
2431
2432	return err;
2433}
2434
2435struct tcf_dump_args {
2436	struct tcf_walker w;
2437	struct sk_buff *skb;
2438	struct netlink_callback *cb;
2439	struct tcf_block *block;
2440	struct Qdisc *q;
2441	u32 parent;
 
2442};
2443
2444static int tcf_node_dump(struct tcf_proto *tp, void *n, struct tcf_walker *arg)
2445{
2446	struct tcf_dump_args *a = (void *)arg;
2447	struct net *net = sock_net(a->skb->sk);
2448
2449	return tcf_fill_node(net, a->skb, tp, a->block, a->q, a->parent,
2450			     n, NETLINK_CB(a->cb->skb).portid,
2451			     a->cb->nlh->nlmsg_seq, NLM_F_MULTI,
2452			     RTM_NEWTFILTER, true);
2453}
2454
2455static bool tcf_chain_dump(struct tcf_chain *chain, struct Qdisc *q, u32 parent,
2456			   struct sk_buff *skb, struct netlink_callback *cb,
2457			   long index_start, long *p_index)
2458{
2459	struct net *net = sock_net(skb->sk);
2460	struct tcf_block *block = chain->block;
2461	struct tcmsg *tcm = nlmsg_data(cb->nlh);
2462	struct tcf_proto *tp, *tp_prev;
2463	struct tcf_dump_args arg;
2464
2465	for (tp = __tcf_get_next_proto(chain, NULL);
2466	     tp;
2467	     tp_prev = tp,
2468		     tp = __tcf_get_next_proto(chain, tp),
2469		     tcf_proto_put(tp_prev, true, NULL),
2470		     (*p_index)++) {
2471		if (*p_index < index_start)
2472			continue;
2473		if (TC_H_MAJ(tcm->tcm_info) &&
2474		    TC_H_MAJ(tcm->tcm_info) != tp->prio)
2475			continue;
2476		if (TC_H_MIN(tcm->tcm_info) &&
2477		    TC_H_MIN(tcm->tcm_info) != tp->protocol)
2478			continue;
2479		if (*p_index > index_start)
2480			memset(&cb->args[1], 0,
2481			       sizeof(cb->args) - sizeof(cb->args[0]));
2482		if (cb->args[1] == 0) {
2483			if (tcf_fill_node(net, skb, tp, block, q, parent, NULL,
2484					  NETLINK_CB(cb->skb).portid,
2485					  cb->nlh->nlmsg_seq, NLM_F_MULTI,
2486					  RTM_NEWTFILTER, true) <= 0)
2487				goto errout;
2488			cb->args[1] = 1;
2489		}
2490		if (!tp->ops->walk)
2491			continue;
2492		arg.w.fn = tcf_node_dump;
2493		arg.skb = skb;
2494		arg.cb = cb;
2495		arg.block = block;
2496		arg.q = q;
2497		arg.parent = parent;
2498		arg.w.stop = 0;
2499		arg.w.skip = cb->args[1] - 1;
2500		arg.w.count = 0;
2501		arg.w.cookie = cb->args[2];
 
2502		tp->ops->walk(tp, &arg.w, true);
2503		cb->args[2] = arg.w.cookie;
2504		cb->args[1] = arg.w.count + 1;
2505		if (arg.w.stop)
2506			goto errout;
2507	}
2508	return true;
2509
2510errout:
2511	tcf_proto_put(tp, true, NULL);
2512	return false;
2513}
2514
 
 
 
 
2515/* called with RTNL */
2516static int tc_dump_tfilter(struct sk_buff *skb, struct netlink_callback *cb)
2517{
2518	struct tcf_chain *chain, *chain_prev;
2519	struct net *net = sock_net(skb->sk);
2520	struct nlattr *tca[TCA_MAX + 1];
2521	struct Qdisc *q = NULL;
2522	struct tcf_block *block;
2523	struct tcmsg *tcm = nlmsg_data(cb->nlh);
 
2524	long index_start;
2525	long index;
2526	u32 parent;
2527	int err;
2528
2529	if (nlmsg_len(cb->nlh) < sizeof(*tcm))
2530		return skb->len;
2531
2532	err = nlmsg_parse_deprecated(cb->nlh, sizeof(*tcm), tca, TCA_MAX,
2533				     NULL, cb->extack);
2534	if (err)
2535		return err;
2536
 
 
 
 
 
 
 
2537	if (tcm->tcm_ifindex == TCM_IFINDEX_MAGIC_BLOCK) {
2538		block = tcf_block_refcnt_get(net, tcm->tcm_block_index);
2539		if (!block)
2540			goto out;
2541		/* If we work with block index, q is NULL and parent value
2542		 * will never be used in the following code. The check
2543		 * in tcf_fill_node prevents it. However, compiler does not
2544		 * see that far, so set parent to zero to silence the warning
2545		 * about parent being uninitialized.
2546		 */
2547		parent = 0;
2548	} else {
2549		const struct Qdisc_class_ops *cops;
2550		struct net_device *dev;
2551		unsigned long cl = 0;
2552
2553		dev = __dev_get_by_index(net, tcm->tcm_ifindex);
2554		if (!dev)
2555			return skb->len;
2556
2557		parent = tcm->tcm_parent;
2558		if (!parent) {
2559			q = dev->qdisc;
2560			parent = q->handle;
2561		} else {
2562			q = qdisc_lookup(dev, TC_H_MAJ(tcm->tcm_parent));
2563		}
2564		if (!q)
2565			goto out;
2566		cops = q->ops->cl_ops;
2567		if (!cops)
2568			goto out;
2569		if (!cops->tcf_block)
2570			goto out;
2571		if (TC_H_MIN(tcm->tcm_parent)) {
2572			cl = cops->find(q, tcm->tcm_parent);
2573			if (cl == 0)
2574				goto out;
2575		}
2576		block = cops->tcf_block(q, cl, NULL);
2577		if (!block)
2578			goto out;
 
2579		if (tcf_block_shared(block))
2580			q = NULL;
2581	}
2582
2583	index_start = cb->args[0];
2584	index = 0;
2585
2586	for (chain = __tcf_get_next_chain(block, NULL);
2587	     chain;
2588	     chain_prev = chain,
2589		     chain = __tcf_get_next_chain(block, chain),
2590		     tcf_chain_put(chain_prev)) {
2591		if (tca[TCA_CHAIN] &&
2592		    nla_get_u32(tca[TCA_CHAIN]) != chain->index)
2593			continue;
2594		if (!tcf_chain_dump(chain, q, parent, skb, cb,
2595				    index_start, &index)) {
2596			tcf_chain_put(chain);
2597			err = -EMSGSIZE;
2598			break;
2599		}
2600	}
2601
2602	if (tcm->tcm_ifindex == TCM_IFINDEX_MAGIC_BLOCK)
2603		tcf_block_refcnt_put(block, true);
2604	cb->args[0] = index;
2605
2606out:
2607	/* If we did no progress, the error (EMSGSIZE) is real */
2608	if (skb->len == 0 && err)
2609		return err;
2610	return skb->len;
2611}
2612
2613static int tc_chain_fill_node(const struct tcf_proto_ops *tmplt_ops,
2614			      void *tmplt_priv, u32 chain_index,
2615			      struct net *net, struct sk_buff *skb,
2616			      struct tcf_block *block,
2617			      u32 portid, u32 seq, u16 flags, int event)
2618{
2619	unsigned char *b = skb_tail_pointer(skb);
2620	const struct tcf_proto_ops *ops;
2621	struct nlmsghdr *nlh;
2622	struct tcmsg *tcm;
2623	void *priv;
2624
2625	ops = tmplt_ops;
2626	priv = tmplt_priv;
2627
2628	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*tcm), flags);
2629	if (!nlh)
2630		goto out_nlmsg_trim;
2631	tcm = nlmsg_data(nlh);
2632	tcm->tcm_family = AF_UNSPEC;
2633	tcm->tcm__pad1 = 0;
2634	tcm->tcm__pad2 = 0;
2635	tcm->tcm_handle = 0;
2636	if (block->q) {
2637		tcm->tcm_ifindex = qdisc_dev(block->q)->ifindex;
2638		tcm->tcm_parent = block->q->handle;
2639	} else {
2640		tcm->tcm_ifindex = TCM_IFINDEX_MAGIC_BLOCK;
2641		tcm->tcm_block_index = block->index;
2642	}
2643
2644	if (nla_put_u32(skb, TCA_CHAIN, chain_index))
2645		goto nla_put_failure;
2646
2647	if (ops) {
2648		if (nla_put_string(skb, TCA_KIND, ops->kind))
2649			goto nla_put_failure;
2650		if (ops->tmplt_dump(skb, net, priv) < 0)
2651			goto nla_put_failure;
2652	}
2653
2654	nlh->nlmsg_len = skb_tail_pointer(skb) - b;
2655	return skb->len;
2656
2657out_nlmsg_trim:
2658nla_put_failure:
2659	nlmsg_trim(skb, b);
2660	return -EMSGSIZE;
2661}
2662
2663static int tc_chain_notify(struct tcf_chain *chain, struct sk_buff *oskb,
2664			   u32 seq, u16 flags, int event, bool unicast)
2665{
2666	u32 portid = oskb ? NETLINK_CB(oskb).portid : 0;
2667	struct tcf_block *block = chain->block;
2668	struct net *net = block->net;
2669	struct sk_buff *skb;
2670	int err = 0;
2671
2672	skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
2673	if (!skb)
2674		return -ENOBUFS;
2675
2676	if (tc_chain_fill_node(chain->tmplt_ops, chain->tmplt_priv,
2677			       chain->index, net, skb, block, portid,
2678			       seq, flags, event) <= 0) {
2679		kfree_skb(skb);
2680		return -EINVAL;
2681	}
2682
2683	if (unicast)
2684		err = netlink_unicast(net->rtnl, skb, portid, MSG_DONTWAIT);
2685	else
2686		err = rtnetlink_send(skb, net, portid, RTNLGRP_TC,
2687				     flags & NLM_F_ECHO);
2688
2689	if (err > 0)
2690		err = 0;
2691	return err;
2692}
2693
2694static int tc_chain_notify_delete(const struct tcf_proto_ops *tmplt_ops,
2695				  void *tmplt_priv, u32 chain_index,
2696				  struct tcf_block *block, struct sk_buff *oskb,
2697				  u32 seq, u16 flags, bool unicast)
2698{
2699	u32 portid = oskb ? NETLINK_CB(oskb).portid : 0;
2700	struct net *net = block->net;
2701	struct sk_buff *skb;
2702
2703	skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
2704	if (!skb)
2705		return -ENOBUFS;
2706
2707	if (tc_chain_fill_node(tmplt_ops, tmplt_priv, chain_index, net, skb,
2708			       block, portid, seq, flags, RTM_DELCHAIN) <= 0) {
2709		kfree_skb(skb);
2710		return -EINVAL;
2711	}
2712
2713	if (unicast)
2714		return netlink_unicast(net->rtnl, skb, portid, MSG_DONTWAIT);
2715
2716	return rtnetlink_send(skb, net, portid, RTNLGRP_TC, flags & NLM_F_ECHO);
2717}
2718
2719static int tc_chain_tmplt_add(struct tcf_chain *chain, struct net *net,
2720			      struct nlattr **tca,
2721			      struct netlink_ext_ack *extack)
2722{
2723	const struct tcf_proto_ops *ops;
 
2724	void *tmplt_priv;
2725
2726	/* If kind is not set, user did not specify template. */
2727	if (!tca[TCA_KIND])
2728		return 0;
2729
2730	ops = tcf_proto_lookup_ops(nla_data(tca[TCA_KIND]), true, extack);
 
 
 
 
 
2731	if (IS_ERR(ops))
2732		return PTR_ERR(ops);
2733	if (!ops->tmplt_create || !ops->tmplt_destroy || !ops->tmplt_dump) {
2734		NL_SET_ERR_MSG(extack, "Chain templates are not supported with specified classifier");
2735		return -EOPNOTSUPP;
2736	}
2737
2738	tmplt_priv = ops->tmplt_create(net, chain, tca, extack);
2739	if (IS_ERR(tmplt_priv)) {
2740		module_put(ops->owner);
2741		return PTR_ERR(tmplt_priv);
2742	}
2743	chain->tmplt_ops = ops;
2744	chain->tmplt_priv = tmplt_priv;
2745	return 0;
2746}
2747
2748static void tc_chain_tmplt_del(const struct tcf_proto_ops *tmplt_ops,
2749			       void *tmplt_priv)
2750{
2751	/* If template ops are set, no work to do for us. */
2752	if (!tmplt_ops)
2753		return;
2754
2755	tmplt_ops->tmplt_destroy(tmplt_priv);
2756	module_put(tmplt_ops->owner);
2757}
2758
2759/* Add/delete/get a chain */
2760
2761static int tc_ctl_chain(struct sk_buff *skb, struct nlmsghdr *n,
2762			struct netlink_ext_ack *extack)
2763{
2764	struct net *net = sock_net(skb->sk);
2765	struct nlattr *tca[TCA_MAX + 1];
2766	struct tcmsg *t;
2767	u32 parent;
2768	u32 chain_index;
2769	struct Qdisc *q = NULL;
2770	struct tcf_chain *chain = NULL;
2771	struct tcf_block *block;
2772	unsigned long cl;
2773	int err;
2774
2775	if (n->nlmsg_type != RTM_GETCHAIN &&
2776	    !netlink_ns_capable(skb, net->user_ns, CAP_NET_ADMIN))
2777		return -EPERM;
2778
2779replay:
2780	err = nlmsg_parse_deprecated(n, sizeof(*t), tca, TCA_MAX,
2781				     rtm_tca_policy, extack);
2782	if (err < 0)
2783		return err;
2784
2785	t = nlmsg_data(n);
2786	parent = t->tcm_parent;
2787	cl = 0;
2788
2789	block = tcf_block_find(net, &q, &parent, &cl,
2790			       t->tcm_ifindex, t->tcm_block_index, extack);
2791	if (IS_ERR(block))
2792		return PTR_ERR(block);
2793
2794	chain_index = tca[TCA_CHAIN] ? nla_get_u32(tca[TCA_CHAIN]) : 0;
2795	if (chain_index > TC_ACT_EXT_VAL_MASK) {
2796		NL_SET_ERR_MSG(extack, "Specified chain index exceeds upper limit");
2797		err = -EINVAL;
2798		goto errout_block;
2799	}
2800
2801	mutex_lock(&block->lock);
2802	chain = tcf_chain_lookup(block, chain_index);
2803	if (n->nlmsg_type == RTM_NEWCHAIN) {
2804		if (chain) {
2805			if (tcf_chain_held_by_acts_only(chain)) {
2806				/* The chain exists only because there is
2807				 * some action referencing it.
2808				 */
2809				tcf_chain_hold(chain);
2810			} else {
2811				NL_SET_ERR_MSG(extack, "Filter chain already exists");
2812				err = -EEXIST;
2813				goto errout_block_locked;
2814			}
2815		} else {
2816			if (!(n->nlmsg_flags & NLM_F_CREATE)) {
2817				NL_SET_ERR_MSG(extack, "Need both RTM_NEWCHAIN and NLM_F_CREATE to create a new chain");
2818				err = -ENOENT;
2819				goto errout_block_locked;
2820			}
2821			chain = tcf_chain_create(block, chain_index);
2822			if (!chain) {
2823				NL_SET_ERR_MSG(extack, "Failed to create filter chain");
2824				err = -ENOMEM;
2825				goto errout_block_locked;
2826			}
2827		}
2828	} else {
2829		if (!chain || tcf_chain_held_by_acts_only(chain)) {
2830			NL_SET_ERR_MSG(extack, "Cannot find specified filter chain");
2831			err = -EINVAL;
2832			goto errout_block_locked;
2833		}
2834		tcf_chain_hold(chain);
2835	}
2836
2837	if (n->nlmsg_type == RTM_NEWCHAIN) {
2838		/* Modifying chain requires holding parent block lock. In case
2839		 * the chain was successfully added, take a reference to the
2840		 * chain. This ensures that an empty chain does not disappear at
2841		 * the end of this function.
2842		 */
2843		tcf_chain_hold(chain);
2844		chain->explicitly_created = true;
2845	}
2846	mutex_unlock(&block->lock);
2847
2848	switch (n->nlmsg_type) {
2849	case RTM_NEWCHAIN:
2850		err = tc_chain_tmplt_add(chain, net, tca, extack);
2851		if (err) {
2852			tcf_chain_put_explicitly_created(chain);
2853			goto errout;
2854		}
2855
2856		tc_chain_notify(chain, NULL, 0, NLM_F_CREATE | NLM_F_EXCL,
2857				RTM_NEWCHAIN, false);
2858		break;
2859	case RTM_DELCHAIN:
2860		tfilter_notify_chain(net, skb, block, q, parent, n,
2861				     chain, RTM_DELTFILTER, true);
2862		/* Flush the chain first as the user requested chain removal. */
2863		tcf_chain_flush(chain, true);
2864		/* In case the chain was successfully deleted, put a reference
2865		 * to the chain previously taken during addition.
2866		 */
2867		tcf_chain_put_explicitly_created(chain);
2868		break;
2869	case RTM_GETCHAIN:
2870		err = tc_chain_notify(chain, skb, n->nlmsg_seq,
2871				      n->nlmsg_seq, n->nlmsg_type, true);
2872		if (err < 0)
2873			NL_SET_ERR_MSG(extack, "Failed to send chain notify message");
2874		break;
2875	default:
2876		err = -EOPNOTSUPP;
2877		NL_SET_ERR_MSG(extack, "Unsupported message type");
2878		goto errout;
2879	}
2880
2881errout:
2882	tcf_chain_put(chain);
2883errout_block:
2884	tcf_block_release(q, block, true);
2885	if (err == -EAGAIN)
2886		/* Replay the request. */
2887		goto replay;
2888	return err;
2889
2890errout_block_locked:
2891	mutex_unlock(&block->lock);
2892	goto errout_block;
2893}
2894
2895/* called with RTNL */
2896static int tc_dump_chain(struct sk_buff *skb, struct netlink_callback *cb)
2897{
2898	struct net *net = sock_net(skb->sk);
2899	struct nlattr *tca[TCA_MAX + 1];
2900	struct Qdisc *q = NULL;
2901	struct tcf_block *block;
2902	struct tcmsg *tcm = nlmsg_data(cb->nlh);
2903	struct tcf_chain *chain;
2904	long index_start;
2905	long index;
2906	u32 parent;
2907	int err;
2908
2909	if (nlmsg_len(cb->nlh) < sizeof(*tcm))
2910		return skb->len;
2911
2912	err = nlmsg_parse_deprecated(cb->nlh, sizeof(*tcm), tca, TCA_MAX,
2913				     rtm_tca_policy, cb->extack);
2914	if (err)
2915		return err;
2916
2917	if (tcm->tcm_ifindex == TCM_IFINDEX_MAGIC_BLOCK) {
2918		block = tcf_block_refcnt_get(net, tcm->tcm_block_index);
2919		if (!block)
2920			goto out;
2921		/* If we work with block index, q is NULL and parent value
2922		 * will never be used in the following code. The check
2923		 * in tcf_fill_node prevents it. However, compiler does not
2924		 * see that far, so set parent to zero to silence the warning
2925		 * about parent being uninitialized.
2926		 */
2927		parent = 0;
2928	} else {
2929		const struct Qdisc_class_ops *cops;
2930		struct net_device *dev;
2931		unsigned long cl = 0;
2932
2933		dev = __dev_get_by_index(net, tcm->tcm_ifindex);
2934		if (!dev)
2935			return skb->len;
2936
2937		parent = tcm->tcm_parent;
2938		if (!parent) {
2939			q = dev->qdisc;
2940			parent = q->handle;
2941		} else {
2942			q = qdisc_lookup(dev, TC_H_MAJ(tcm->tcm_parent));
2943		}
2944		if (!q)
2945			goto out;
2946		cops = q->ops->cl_ops;
2947		if (!cops)
2948			goto out;
2949		if (!cops->tcf_block)
2950			goto out;
2951		if (TC_H_MIN(tcm->tcm_parent)) {
2952			cl = cops->find(q, tcm->tcm_parent);
2953			if (cl == 0)
2954				goto out;
2955		}
2956		block = cops->tcf_block(q, cl, NULL);
2957		if (!block)
2958			goto out;
2959		if (tcf_block_shared(block))
2960			q = NULL;
2961	}
2962
2963	index_start = cb->args[0];
2964	index = 0;
2965
2966	mutex_lock(&block->lock);
2967	list_for_each_entry(chain, &block->chain_list, list) {
2968		if ((tca[TCA_CHAIN] &&
2969		     nla_get_u32(tca[TCA_CHAIN]) != chain->index))
2970			continue;
2971		if (index < index_start) {
2972			index++;
2973			continue;
2974		}
2975		if (tcf_chain_held_by_acts_only(chain))
2976			continue;
2977		err = tc_chain_fill_node(chain->tmplt_ops, chain->tmplt_priv,
2978					 chain->index, net, skb, block,
2979					 NETLINK_CB(cb->skb).portid,
2980					 cb->nlh->nlmsg_seq, NLM_F_MULTI,
2981					 RTM_NEWCHAIN);
2982		if (err <= 0)
2983			break;
2984		index++;
2985	}
2986	mutex_unlock(&block->lock);
2987
2988	if (tcm->tcm_ifindex == TCM_IFINDEX_MAGIC_BLOCK)
2989		tcf_block_refcnt_put(block, true);
2990	cb->args[0] = index;
2991
2992out:
2993	/* If we did no progress, the error (EMSGSIZE) is real */
2994	if (skb->len == 0 && err)
2995		return err;
2996	return skb->len;
2997}
2998
2999void tcf_exts_destroy(struct tcf_exts *exts)
3000{
3001#ifdef CONFIG_NET_CLS_ACT
3002	if (exts->actions) {
3003		tcf_action_destroy(exts->actions, TCA_ACT_UNBIND);
3004		kfree(exts->actions);
3005	}
3006	exts->nr_actions = 0;
3007#endif
3008}
3009EXPORT_SYMBOL(tcf_exts_destroy);
3010
3011int tcf_exts_validate(struct net *net, struct tcf_proto *tp, struct nlattr **tb,
3012		      struct nlattr *rate_tlv, struct tcf_exts *exts, bool ovr,
3013		      bool rtnl_held, struct netlink_ext_ack *extack)
3014{
3015#ifdef CONFIG_NET_CLS_ACT
3016	{
 
3017		struct tc_action *act;
3018		size_t attr_size = 0;
3019
3020		if (exts->police && tb[exts->police]) {
 
 
 
 
 
3021			act = tcf_action_init_1(net, tp, tb[exts->police],
3022						rate_tlv, "police", ovr,
3023						TCA_ACT_BIND, rtnl_held,
3024						extack);
 
3025			if (IS_ERR(act))
3026				return PTR_ERR(act);
3027
3028			act->type = exts->type = TCA_OLD_COMPAT;
3029			exts->actions[0] = act;
3030			exts->nr_actions = 1;
 
3031		} else if (exts->action && tb[exts->action]) {
3032			int err;
3033
3034			err = tcf_action_init(net, tp, tb[exts->action],
3035					      rate_tlv, NULL, ovr, TCA_ACT_BIND,
3036					      exts->actions, &attr_size,
3037					      rtnl_held, extack);
3038			if (err < 0)
3039				return err;
3040			exts->nr_actions = err;
3041		}
3042	}
3043#else
3044	if ((exts->action && tb[exts->action]) ||
3045	    (exts->police && tb[exts->police])) {
3046		NL_SET_ERR_MSG(extack, "Classifier actions are not supported per compile options (CONFIG_NET_CLS_ACT)");
3047		return -EOPNOTSUPP;
3048	}
3049#endif
3050
3051	return 0;
3052}
3053EXPORT_SYMBOL(tcf_exts_validate);
3054
3055void tcf_exts_change(struct tcf_exts *dst, struct tcf_exts *src)
3056{
3057#ifdef CONFIG_NET_CLS_ACT
3058	struct tcf_exts old = *dst;
3059
3060	*dst = *src;
3061	tcf_exts_destroy(&old);
3062#endif
3063}
3064EXPORT_SYMBOL(tcf_exts_change);
3065
3066#ifdef CONFIG_NET_CLS_ACT
3067static struct tc_action *tcf_exts_first_act(struct tcf_exts *exts)
3068{
3069	if (exts->nr_actions == 0)
3070		return NULL;
3071	else
3072		return exts->actions[0];
3073}
3074#endif
3075
3076int tcf_exts_dump(struct sk_buff *skb, struct tcf_exts *exts)
3077{
3078#ifdef CONFIG_NET_CLS_ACT
3079	struct nlattr *nest;
3080
3081	if (exts->action && tcf_exts_has_actions(exts)) {
3082		/*
3083		 * again for backward compatible mode - we want
3084		 * to work with both old and new modes of entering
3085		 * tc data even if iproute2  was newer - jhs
3086		 */
3087		if (exts->type != TCA_OLD_COMPAT) {
3088			nest = nla_nest_start_noflag(skb, exts->action);
3089			if (nest == NULL)
3090				goto nla_put_failure;
3091
3092			if (tcf_action_dump(skb, exts->actions, 0, 0) < 0)
 
3093				goto nla_put_failure;
3094			nla_nest_end(skb, nest);
3095		} else if (exts->police) {
3096			struct tc_action *act = tcf_exts_first_act(exts);
3097			nest = nla_nest_start_noflag(skb, exts->police);
3098			if (nest == NULL || !act)
3099				goto nla_put_failure;
3100			if (tcf_action_dump_old(skb, act, 0, 0) < 0)
3101				goto nla_put_failure;
3102			nla_nest_end(skb, nest);
3103		}
3104	}
3105	return 0;
3106
3107nla_put_failure:
3108	nla_nest_cancel(skb, nest);
3109	return -1;
3110#else
3111	return 0;
3112#endif
3113}
3114EXPORT_SYMBOL(tcf_exts_dump);
3115
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3116
3117int tcf_exts_dump_stats(struct sk_buff *skb, struct tcf_exts *exts)
3118{
3119#ifdef CONFIG_NET_CLS_ACT
3120	struct tc_action *a = tcf_exts_first_act(exts);
3121	if (a != NULL && tcf_action_copy_stats(skb, a, 1) < 0)
3122		return -1;
3123#endif
3124	return 0;
3125}
3126EXPORT_SYMBOL(tcf_exts_dump_stats);
3127
3128static void tcf_block_offload_inc(struct tcf_block *block, u32 *flags)
3129{
3130	if (*flags & TCA_CLS_FLAGS_IN_HW)
3131		return;
3132	*flags |= TCA_CLS_FLAGS_IN_HW;
3133	atomic_inc(&block->offloadcnt);
3134}
3135
3136static void tcf_block_offload_dec(struct tcf_block *block, u32 *flags)
3137{
3138	if (!(*flags & TCA_CLS_FLAGS_IN_HW))
3139		return;
3140	*flags &= ~TCA_CLS_FLAGS_IN_HW;
3141	atomic_dec(&block->offloadcnt);
3142}
3143
3144static void tc_cls_offload_cnt_update(struct tcf_block *block,
3145				      struct tcf_proto *tp, u32 *cnt,
3146				      u32 *flags, u32 diff, bool add)
3147{
3148	lockdep_assert_held(&block->cb_lock);
3149
3150	spin_lock(&tp->lock);
3151	if (add) {
3152		if (!*cnt)
3153			tcf_block_offload_inc(block, flags);
3154		*cnt += diff;
3155	} else {
3156		*cnt -= diff;
3157		if (!*cnt)
3158			tcf_block_offload_dec(block, flags);
3159	}
3160	spin_unlock(&tp->lock);
3161}
3162
3163static void
3164tc_cls_offload_cnt_reset(struct tcf_block *block, struct tcf_proto *tp,
3165			 u32 *cnt, u32 *flags)
3166{
3167	lockdep_assert_held(&block->cb_lock);
3168
3169	spin_lock(&tp->lock);
3170	tcf_block_offload_dec(block, flags);
3171	*cnt = 0;
3172	spin_unlock(&tp->lock);
3173}
3174
3175static int
3176__tc_setup_cb_call(struct tcf_block *block, enum tc_setup_type type,
3177		   void *type_data, bool err_stop)
3178{
3179	struct flow_block_cb *block_cb;
3180	int ok_count = 0;
3181	int err;
3182
3183	list_for_each_entry(block_cb, &block->flow_block.cb_list, list) {
3184		err = block_cb->cb(type, type_data, block_cb->cb_priv);
3185		if (err) {
3186			if (err_stop)
3187				return err;
3188		} else {
3189			ok_count++;
3190		}
3191	}
3192	return ok_count;
3193}
3194
3195int tc_setup_cb_call(struct tcf_block *block, enum tc_setup_type type,
3196		     void *type_data, bool err_stop, bool rtnl_held)
3197{
3198	bool take_rtnl = READ_ONCE(block->lockeddevcnt) && !rtnl_held;
3199	int ok_count;
3200
3201retry:
3202	if (take_rtnl)
3203		rtnl_lock();
3204	down_read(&block->cb_lock);
3205	/* Need to obtain rtnl lock if block is bound to devs that require it.
3206	 * In block bind code cb_lock is obtained while holding rtnl, so we must
3207	 * obtain the locks in same order here.
3208	 */
3209	if (!rtnl_held && !take_rtnl && block->lockeddevcnt) {
3210		up_read(&block->cb_lock);
3211		take_rtnl = true;
3212		goto retry;
3213	}
3214
3215	ok_count = __tc_setup_cb_call(block, type, type_data, err_stop);
3216
3217	up_read(&block->cb_lock);
3218	if (take_rtnl)
3219		rtnl_unlock();
3220	return ok_count;
3221}
3222EXPORT_SYMBOL(tc_setup_cb_call);
3223
3224/* Non-destructive filter add. If filter that wasn't already in hardware is
3225 * successfully offloaded, increment block offloads counter. On failure,
3226 * previously offloaded filter is considered to be intact and offloads counter
3227 * is not decremented.
3228 */
3229
3230int tc_setup_cb_add(struct tcf_block *block, struct tcf_proto *tp,
3231		    enum tc_setup_type type, void *type_data, bool err_stop,
3232		    u32 *flags, unsigned int *in_hw_count, bool rtnl_held)
3233{
3234	bool take_rtnl = READ_ONCE(block->lockeddevcnt) && !rtnl_held;
3235	int ok_count;
3236
3237retry:
3238	if (take_rtnl)
3239		rtnl_lock();
3240	down_read(&block->cb_lock);
3241	/* Need to obtain rtnl lock if block is bound to devs that require it.
3242	 * In block bind code cb_lock is obtained while holding rtnl, so we must
3243	 * obtain the locks in same order here.
3244	 */
3245	if (!rtnl_held && !take_rtnl && block->lockeddevcnt) {
3246		up_read(&block->cb_lock);
3247		take_rtnl = true;
3248		goto retry;
3249	}
3250
3251	/* Make sure all netdevs sharing this block are offload-capable. */
3252	if (block->nooffloaddevcnt && err_stop) {
3253		ok_count = -EOPNOTSUPP;
3254		goto err_unlock;
3255	}
3256
3257	ok_count = __tc_setup_cb_call(block, type, type_data, err_stop);
3258	if (ok_count < 0)
3259		goto err_unlock;
3260
3261	if (tp->ops->hw_add)
3262		tp->ops->hw_add(tp, type_data);
3263	if (ok_count > 0)
3264		tc_cls_offload_cnt_update(block, tp, in_hw_count, flags,
3265					  ok_count, true);
3266err_unlock:
3267	up_read(&block->cb_lock);
3268	if (take_rtnl)
3269		rtnl_unlock();
3270	return ok_count < 0 ? ok_count : 0;
3271}
3272EXPORT_SYMBOL(tc_setup_cb_add);
3273
3274/* Destructive filter replace. If filter that wasn't already in hardware is
3275 * successfully offloaded, increment block offload counter. On failure,
3276 * previously offloaded filter is considered to be destroyed and offload counter
3277 * is decremented.
3278 */
3279
3280int tc_setup_cb_replace(struct tcf_block *block, struct tcf_proto *tp,
3281			enum tc_setup_type type, void *type_data, bool err_stop,
3282			u32 *old_flags, unsigned int *old_in_hw_count,
3283			u32 *new_flags, unsigned int *new_in_hw_count,
3284			bool rtnl_held)
3285{
3286	bool take_rtnl = READ_ONCE(block->lockeddevcnt) && !rtnl_held;
3287	int ok_count;
3288
3289retry:
3290	if (take_rtnl)
3291		rtnl_lock();
3292	down_read(&block->cb_lock);
3293	/* Need to obtain rtnl lock if block is bound to devs that require it.
3294	 * In block bind code cb_lock is obtained while holding rtnl, so we must
3295	 * obtain the locks in same order here.
3296	 */
3297	if (!rtnl_held && !take_rtnl && block->lockeddevcnt) {
3298		up_read(&block->cb_lock);
3299		take_rtnl = true;
3300		goto retry;
3301	}
3302
3303	/* Make sure all netdevs sharing this block are offload-capable. */
3304	if (block->nooffloaddevcnt && err_stop) {
3305		ok_count = -EOPNOTSUPP;
3306		goto err_unlock;
3307	}
3308
3309	tc_cls_offload_cnt_reset(block, tp, old_in_hw_count, old_flags);
3310	if (tp->ops->hw_del)
3311		tp->ops->hw_del(tp, type_data);
3312
3313	ok_count = __tc_setup_cb_call(block, type, type_data, err_stop);
3314	if (ok_count < 0)
3315		goto err_unlock;
3316
3317	if (tp->ops->hw_add)
3318		tp->ops->hw_add(tp, type_data);
3319	if (ok_count > 0)
3320		tc_cls_offload_cnt_update(block, tp, new_in_hw_count,
3321					  new_flags, ok_count, true);
3322err_unlock:
3323	up_read(&block->cb_lock);
3324	if (take_rtnl)
3325		rtnl_unlock();
3326	return ok_count < 0 ? ok_count : 0;
3327}
3328EXPORT_SYMBOL(tc_setup_cb_replace);
3329
3330/* Destroy filter and decrement block offload counter, if filter was previously
3331 * offloaded.
3332 */
3333
3334int tc_setup_cb_destroy(struct tcf_block *block, struct tcf_proto *tp,
3335			enum tc_setup_type type, void *type_data, bool err_stop,
3336			u32 *flags, unsigned int *in_hw_count, bool rtnl_held)
3337{
3338	bool take_rtnl = READ_ONCE(block->lockeddevcnt) && !rtnl_held;
3339	int ok_count;
3340
3341retry:
3342	if (take_rtnl)
3343		rtnl_lock();
3344	down_read(&block->cb_lock);
3345	/* Need to obtain rtnl lock if block is bound to devs that require it.
3346	 * In block bind code cb_lock is obtained while holding rtnl, so we must
3347	 * obtain the locks in same order here.
3348	 */
3349	if (!rtnl_held && !take_rtnl && block->lockeddevcnt) {
3350		up_read(&block->cb_lock);
3351		take_rtnl = true;
3352		goto retry;
3353	}
3354
3355	ok_count = __tc_setup_cb_call(block, type, type_data, err_stop);
3356
3357	tc_cls_offload_cnt_reset(block, tp, in_hw_count, flags);
3358	if (tp->ops->hw_del)
3359		tp->ops->hw_del(tp, type_data);
3360
3361	up_read(&block->cb_lock);
3362	if (take_rtnl)
3363		rtnl_unlock();
3364	return ok_count < 0 ? ok_count : 0;
3365}
3366EXPORT_SYMBOL(tc_setup_cb_destroy);
3367
3368int tc_setup_cb_reoffload(struct tcf_block *block, struct tcf_proto *tp,
3369			  bool add, flow_setup_cb_t *cb,
3370			  enum tc_setup_type type, void *type_data,
3371			  void *cb_priv, u32 *flags, unsigned int *in_hw_count)
3372{
3373	int err = cb(type, type_data, cb_priv);
3374
3375	if (err) {
3376		if (add && tc_skip_sw(*flags))
3377			return err;
3378	} else {
3379		tc_cls_offload_cnt_update(block, tp, in_hw_count, flags, 1,
3380					  add);
3381	}
3382
3383	return 0;
3384}
3385EXPORT_SYMBOL(tc_setup_cb_reoffload);
3386
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3387void tc_cleanup_flow_action(struct flow_action *flow_action)
3388{
3389	struct flow_action_entry *entry;
3390	int i;
3391
3392	flow_action_for_each(i, entry, flow_action)
 
3393		if (entry->destructor)
3394			entry->destructor(entry->destructor_priv);
 
3395}
3396EXPORT_SYMBOL(tc_cleanup_flow_action);
3397
3398static void tcf_mirred_get_dev(struct flow_action_entry *entry,
3399			       const struct tc_action *act)
3400{
3401#ifdef CONFIG_NET_CLS_ACT
3402	entry->dev = act->ops->get_dev(act, &entry->destructor);
3403	if (!entry->dev)
3404		return;
3405	entry->destructor_priv = entry->dev;
3406#endif
3407}
3408
3409static void tcf_tunnel_encap_put_tunnel(void *priv)
3410{
3411	struct ip_tunnel_info *tunnel = priv;
3412
3413	kfree(tunnel);
3414}
3415
3416static int tcf_tunnel_encap_get_tunnel(struct flow_action_entry *entry,
3417				       const struct tc_action *act)
3418{
3419	entry->tunnel = tcf_tunnel_info_copy(act);
3420	if (!entry->tunnel)
3421		return -ENOMEM;
3422	entry->destructor = tcf_tunnel_encap_put_tunnel;
3423	entry->destructor_priv = entry->tunnel;
3424	return 0;
3425}
3426
3427static void tcf_sample_get_group(struct flow_action_entry *entry,
3428				 const struct tc_action *act)
3429{
3430#ifdef CONFIG_NET_CLS_ACT
3431	entry->sample.psample_group =
3432		act->ops->get_psample_group(act, &entry->destructor);
3433	entry->destructor_priv = entry->sample.psample_group;
3434#endif
3435}
3436
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3437int tc_setup_flow_action(struct flow_action *flow_action,
3438			 const struct tcf_exts *exts, bool rtnl_held)
3439{
3440	const struct tc_action *act;
3441	int i, j, k, err = 0;
3442
 
 
 
 
3443	if (!exts)
3444		return 0;
3445
3446	if (!rtnl_held)
3447		rtnl_lock();
3448
3449	j = 0;
3450	tcf_exts_for_each_action(i, act, exts) {
3451		struct flow_action_entry *entry;
3452
3453		entry = &flow_action->entries[j];
 
 
 
 
 
 
 
3454		if (is_tcf_gact_ok(act)) {
3455			entry->id = FLOW_ACTION_ACCEPT;
3456		} else if (is_tcf_gact_shot(act)) {
3457			entry->id = FLOW_ACTION_DROP;
3458		} else if (is_tcf_gact_trap(act)) {
3459			entry->id = FLOW_ACTION_TRAP;
3460		} else if (is_tcf_gact_goto_chain(act)) {
3461			entry->id = FLOW_ACTION_GOTO;
3462			entry->chain_index = tcf_gact_goto_chain_index(act);
3463		} else if (is_tcf_mirred_egress_redirect(act)) {
3464			entry->id = FLOW_ACTION_REDIRECT;
3465			tcf_mirred_get_dev(entry, act);
3466		} else if (is_tcf_mirred_egress_mirror(act)) {
3467			entry->id = FLOW_ACTION_MIRRED;
3468			tcf_mirred_get_dev(entry, act);
3469		} else if (is_tcf_mirred_ingress_redirect(act)) {
3470			entry->id = FLOW_ACTION_REDIRECT_INGRESS;
3471			tcf_mirred_get_dev(entry, act);
3472		} else if (is_tcf_mirred_ingress_mirror(act)) {
3473			entry->id = FLOW_ACTION_MIRRED_INGRESS;
3474			tcf_mirred_get_dev(entry, act);
3475		} else if (is_tcf_vlan(act)) {
3476			switch (tcf_vlan_action(act)) {
3477			case TCA_VLAN_ACT_PUSH:
3478				entry->id = FLOW_ACTION_VLAN_PUSH;
3479				entry->vlan.vid = tcf_vlan_push_vid(act);
3480				entry->vlan.proto = tcf_vlan_push_proto(act);
3481				entry->vlan.prio = tcf_vlan_push_prio(act);
3482				break;
3483			case TCA_VLAN_ACT_POP:
3484				entry->id = FLOW_ACTION_VLAN_POP;
3485				break;
3486			case TCA_VLAN_ACT_MODIFY:
3487				entry->id = FLOW_ACTION_VLAN_MANGLE;
3488				entry->vlan.vid = tcf_vlan_push_vid(act);
3489				entry->vlan.proto = tcf_vlan_push_proto(act);
3490				entry->vlan.prio = tcf_vlan_push_prio(act);
3491				break;
3492			default:
3493				err = -EOPNOTSUPP;
3494				goto err_out;
3495			}
3496		} else if (is_tcf_tunnel_set(act)) {
3497			entry->id = FLOW_ACTION_TUNNEL_ENCAP;
3498			err = tcf_tunnel_encap_get_tunnel(entry, act);
3499			if (err)
3500				goto err_out;
3501		} else if (is_tcf_tunnel_release(act)) {
3502			entry->id = FLOW_ACTION_TUNNEL_DECAP;
3503		} else if (is_tcf_pedit(act)) {
3504			for (k = 0; k < tcf_pedit_nkeys(act); k++) {
3505				switch (tcf_pedit_cmd(act, k)) {
3506				case TCA_PEDIT_KEY_EX_CMD_SET:
3507					entry->id = FLOW_ACTION_MANGLE;
3508					break;
3509				case TCA_PEDIT_KEY_EX_CMD_ADD:
3510					entry->id = FLOW_ACTION_ADD;
3511					break;
3512				default:
3513					err = -EOPNOTSUPP;
3514					goto err_out;
3515				}
3516				entry->mangle.htype = tcf_pedit_htype(act, k);
3517				entry->mangle.mask = tcf_pedit_mask(act, k);
3518				entry->mangle.val = tcf_pedit_val(act, k);
3519				entry->mangle.offset = tcf_pedit_offset(act, k);
 
3520				entry = &flow_action->entries[++j];
3521			}
3522		} else if (is_tcf_csum(act)) {
3523			entry->id = FLOW_ACTION_CSUM;
3524			entry->csum_flags = tcf_csum_update_flags(act);
3525		} else if (is_tcf_skbedit_mark(act)) {
3526			entry->id = FLOW_ACTION_MARK;
3527			entry->mark = tcf_skbedit_mark(act);
3528		} else if (is_tcf_sample(act)) {
3529			entry->id = FLOW_ACTION_SAMPLE;
3530			entry->sample.trunc_size = tcf_sample_trunc_size(act);
3531			entry->sample.truncate = tcf_sample_truncate(act);
3532			entry->sample.rate = tcf_sample_rate(act);
3533			tcf_sample_get_group(entry, act);
3534		} else if (is_tcf_police(act)) {
3535			entry->id = FLOW_ACTION_POLICE;
3536			entry->police.burst = tcf_police_tcfp_burst(act);
3537			entry->police.rate_bytes_ps =
3538				tcf_police_rate_bytes_ps(act);
 
 
 
 
 
3539		} else if (is_tcf_ct(act)) {
3540			entry->id = FLOW_ACTION_CT;
3541			entry->ct.action = tcf_ct_action(act);
3542			entry->ct.zone = tcf_ct_zone(act);
 
3543		} else if (is_tcf_mpls(act)) {
3544			switch (tcf_mpls_action(act)) {
3545			case TCA_MPLS_ACT_PUSH:
3546				entry->id = FLOW_ACTION_MPLS_PUSH;
3547				entry->mpls_push.proto = tcf_mpls_proto(act);
3548				entry->mpls_push.label = tcf_mpls_label(act);
3549				entry->mpls_push.tc = tcf_mpls_tc(act);
3550				entry->mpls_push.bos = tcf_mpls_bos(act);
3551				entry->mpls_push.ttl = tcf_mpls_ttl(act);
3552				break;
3553			case TCA_MPLS_ACT_POP:
3554				entry->id = FLOW_ACTION_MPLS_POP;
3555				entry->mpls_pop.proto = tcf_mpls_proto(act);
3556				break;
3557			case TCA_MPLS_ACT_MODIFY:
3558				entry->id = FLOW_ACTION_MPLS_MANGLE;
3559				entry->mpls_mangle.label = tcf_mpls_label(act);
3560				entry->mpls_mangle.tc = tcf_mpls_tc(act);
3561				entry->mpls_mangle.bos = tcf_mpls_bos(act);
3562				entry->mpls_mangle.ttl = tcf_mpls_ttl(act);
3563				break;
3564			default:
3565				goto err_out;
3566			}
3567		} else if (is_tcf_skbedit_ptype(act)) {
3568			entry->id = FLOW_ACTION_PTYPE;
3569			entry->ptype = tcf_skbedit_ptype(act);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3570		} else {
3571			err = -EOPNOTSUPP;
3572			goto err_out;
3573		}
 
3574
3575		if (!is_tcf_pedit(act))
3576			j++;
3577	}
3578
3579err_out:
3580	if (!rtnl_held)
3581		rtnl_unlock();
3582
3583	if (err)
3584		tc_cleanup_flow_action(flow_action);
3585
3586	return err;
 
 
 
3587}
3588EXPORT_SYMBOL(tc_setup_flow_action);
3589
3590unsigned int tcf_exts_num_actions(struct tcf_exts *exts)
3591{
3592	unsigned int num_acts = 0;
3593	struct tc_action *act;
3594	int i;
3595
3596	tcf_exts_for_each_action(i, act, exts) {
3597		if (is_tcf_pedit(act))
3598			num_acts += tcf_pedit_nkeys(act);
3599		else
3600			num_acts++;
3601	}
3602	return num_acts;
3603}
3604EXPORT_SYMBOL(tcf_exts_num_actions);
3605
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3606static __net_init int tcf_net_init(struct net *net)
3607{
3608	struct tcf_net *tn = net_generic(net, tcf_net_id);
3609
3610	spin_lock_init(&tn->idr_lock);
3611	idr_init(&tn->idr);
3612	return 0;
3613}
3614
3615static void __net_exit tcf_net_exit(struct net *net)
3616{
3617	struct tcf_net *tn = net_generic(net, tcf_net_id);
3618
3619	idr_destroy(&tn->idr);
3620}
3621
3622static struct pernet_operations tcf_net_ops = {
3623	.init = tcf_net_init,
3624	.exit = tcf_net_exit,
3625	.id   = &tcf_net_id,
3626	.size = sizeof(struct tcf_net),
3627};
3628
3629static struct flow_indr_block_ing_entry block_ing_entry = {
3630	.cb = tc_indr_block_get_and_ing_cmd,
3631	.list = LIST_HEAD_INIT(block_ing_entry.list),
3632};
3633
3634static int __init tc_filter_init(void)
3635{
3636	int err;
3637
3638	tc_filter_wq = alloc_ordered_workqueue("tc_filter_workqueue", 0);
3639	if (!tc_filter_wq)
3640		return -ENOMEM;
3641
3642	err = register_pernet_subsys(&tcf_net_ops);
3643	if (err)
3644		goto err_register_pernet_subsys;
3645
3646	flow_indr_add_block_ing_cb(&block_ing_entry);
3647
3648	rtnl_register(PF_UNSPEC, RTM_NEWTFILTER, tc_new_tfilter, NULL,
3649		      RTNL_FLAG_DOIT_UNLOCKED);
3650	rtnl_register(PF_UNSPEC, RTM_DELTFILTER, tc_del_tfilter, NULL,
3651		      RTNL_FLAG_DOIT_UNLOCKED);
3652	rtnl_register(PF_UNSPEC, RTM_GETTFILTER, tc_get_tfilter,
3653		      tc_dump_tfilter, RTNL_FLAG_DOIT_UNLOCKED);
3654	rtnl_register(PF_UNSPEC, RTM_NEWCHAIN, tc_ctl_chain, NULL, 0);
3655	rtnl_register(PF_UNSPEC, RTM_DELCHAIN, tc_ctl_chain, NULL, 0);
3656	rtnl_register(PF_UNSPEC, RTM_GETCHAIN, tc_ctl_chain,
3657		      tc_dump_chain, 0);
3658
3659	return 0;
3660
3661err_register_pernet_subsys:
3662	destroy_workqueue(tc_filter_wq);
3663	return err;
3664}
3665
3666subsys_initcall(tc_filter_init);
v5.14.15
   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/jhash.h>
  24#include <linux/rculist.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/tc_act/tc_gate.h>
  42#include <net/flow_offload.h>
  43
  44extern const struct nla_policy rtm_tca_policy[TCA_MAX + 1];
  45
  46/* The list of all installed classifier types */
  47static LIST_HEAD(tcf_proto_base);
  48
  49/* Protects list of registered TC modules. It is pure SMP lock. */
  50static DEFINE_RWLOCK(cls_mod_lock);
  51
  52static u32 destroy_obj_hashfn(const struct tcf_proto *tp)
  53{
  54	return jhash_3words(tp->chain->index, tp->prio,
  55			    (__force __u32)tp->protocol, 0);
  56}
  57
  58static void tcf_proto_signal_destroying(struct tcf_chain *chain,
  59					struct tcf_proto *tp)
  60{
  61	struct tcf_block *block = chain->block;
  62
  63	mutex_lock(&block->proto_destroy_lock);
  64	hash_add_rcu(block->proto_destroy_ht, &tp->destroy_ht_node,
  65		     destroy_obj_hashfn(tp));
  66	mutex_unlock(&block->proto_destroy_lock);
  67}
  68
  69static bool tcf_proto_cmp(const struct tcf_proto *tp1,
  70			  const struct tcf_proto *tp2)
  71{
  72	return tp1->chain->index == tp2->chain->index &&
  73	       tp1->prio == tp2->prio &&
  74	       tp1->protocol == tp2->protocol;
  75}
  76
  77static bool tcf_proto_exists_destroying(struct tcf_chain *chain,
  78					struct tcf_proto *tp)
  79{
  80	u32 hash = destroy_obj_hashfn(tp);
  81	struct tcf_proto *iter;
  82	bool found = false;
  83
  84	rcu_read_lock();
  85	hash_for_each_possible_rcu(chain->block->proto_destroy_ht, iter,
  86				   destroy_ht_node, hash) {
  87		if (tcf_proto_cmp(tp, iter)) {
  88			found = true;
  89			break;
  90		}
  91	}
  92	rcu_read_unlock();
  93
  94	return found;
  95}
  96
  97static void
  98tcf_proto_signal_destroyed(struct tcf_chain *chain, struct tcf_proto *tp)
  99{
 100	struct tcf_block *block = chain->block;
 101
 102	mutex_lock(&block->proto_destroy_lock);
 103	if (hash_hashed(&tp->destroy_ht_node))
 104		hash_del_rcu(&tp->destroy_ht_node);
 105	mutex_unlock(&block->proto_destroy_lock);
 106}
 107
 108/* Find classifier type by string name */
 109
 110static const struct tcf_proto_ops *__tcf_proto_lookup_ops(const char *kind)
 111{
 112	const struct tcf_proto_ops *t, *res = NULL;
 113
 114	if (kind) {
 115		read_lock(&cls_mod_lock);
 116		list_for_each_entry(t, &tcf_proto_base, head) {
 117			if (strcmp(kind, t->kind) == 0) {
 118				if (try_module_get(t->owner))
 119					res = t;
 120				break;
 121			}
 122		}
 123		read_unlock(&cls_mod_lock);
 124	}
 125	return res;
 126}
 127
 128static const struct tcf_proto_ops *
 129tcf_proto_lookup_ops(const char *kind, bool rtnl_held,
 130		     struct netlink_ext_ack *extack)
 131{
 132	const struct tcf_proto_ops *ops;
 133
 134	ops = __tcf_proto_lookup_ops(kind);
 135	if (ops)
 136		return ops;
 137#ifdef CONFIG_MODULES
 138	if (rtnl_held)
 139		rtnl_unlock();
 140	request_module("cls_%s", kind);
 141	if (rtnl_held)
 142		rtnl_lock();
 143	ops = __tcf_proto_lookup_ops(kind);
 144	/* We dropped the RTNL semaphore in order to perform
 145	 * the module load. So, even if we succeeded in loading
 146	 * the module we have to replay the request. We indicate
 147	 * this using -EAGAIN.
 148	 */
 149	if (ops) {
 150		module_put(ops->owner);
 151		return ERR_PTR(-EAGAIN);
 152	}
 153#endif
 154	NL_SET_ERR_MSG(extack, "TC classifier not found");
 155	return ERR_PTR(-ENOENT);
 156}
 157
 158/* Register(unregister) new classifier type */
 159
 160int register_tcf_proto_ops(struct tcf_proto_ops *ops)
 161{
 162	struct tcf_proto_ops *t;
 163	int rc = -EEXIST;
 164
 165	write_lock(&cls_mod_lock);
 166	list_for_each_entry(t, &tcf_proto_base, head)
 167		if (!strcmp(ops->kind, t->kind))
 168			goto out;
 169
 170	list_add_tail(&ops->head, &tcf_proto_base);
 171	rc = 0;
 172out:
 173	write_unlock(&cls_mod_lock);
 174	return rc;
 175}
 176EXPORT_SYMBOL(register_tcf_proto_ops);
 177
 178static struct workqueue_struct *tc_filter_wq;
 179
 180int unregister_tcf_proto_ops(struct tcf_proto_ops *ops)
 181{
 182	struct tcf_proto_ops *t;
 183	int rc = -ENOENT;
 184
 185	/* Wait for outstanding call_rcu()s, if any, from a
 186	 * tcf_proto_ops's destroy() handler.
 187	 */
 188	rcu_barrier();
 189	flush_workqueue(tc_filter_wq);
 190
 191	write_lock(&cls_mod_lock);
 192	list_for_each_entry(t, &tcf_proto_base, head) {
 193		if (t == ops) {
 194			list_del(&t->head);
 195			rc = 0;
 196			break;
 197		}
 198	}
 199	write_unlock(&cls_mod_lock);
 200	return rc;
 201}
 202EXPORT_SYMBOL(unregister_tcf_proto_ops);
 203
 204bool tcf_queue_work(struct rcu_work *rwork, work_func_t func)
 205{
 206	INIT_RCU_WORK(rwork, func);
 207	return queue_rcu_work(tc_filter_wq, rwork);
 208}
 209EXPORT_SYMBOL(tcf_queue_work);
 210
 211/* Select new prio value from the range, managed by kernel. */
 212
 213static inline u32 tcf_auto_prio(struct tcf_proto *tp)
 214{
 215	u32 first = TC_H_MAKE(0xC0000000U, 0U);
 216
 217	if (tp)
 218		first = tp->prio - 1;
 219
 220	return TC_H_MAJ(first);
 221}
 222
 223static bool tcf_proto_check_kind(struct nlattr *kind, char *name)
 224{
 225	if (kind)
 226		return nla_strscpy(name, kind, IFNAMSIZ) < 0;
 227	memset(name, 0, IFNAMSIZ);
 228	return false;
 229}
 230
 231static bool tcf_proto_is_unlocked(const char *kind)
 232{
 233	const struct tcf_proto_ops *ops;
 234	bool ret;
 235
 236	if (strlen(kind) == 0)
 237		return false;
 238
 239	ops = tcf_proto_lookup_ops(kind, false, NULL);
 240	/* On error return false to take rtnl lock. Proto lookup/create
 241	 * functions will perform lookup again and properly handle errors.
 242	 */
 243	if (IS_ERR(ops))
 244		return false;
 245
 246	ret = !!(ops->flags & TCF_PROTO_OPS_DOIT_UNLOCKED);
 247	module_put(ops->owner);
 248	return ret;
 249}
 250
 251static struct tcf_proto *tcf_proto_create(const char *kind, u32 protocol,
 252					  u32 prio, struct tcf_chain *chain,
 253					  bool rtnl_held,
 254					  struct netlink_ext_ack *extack)
 255{
 256	struct tcf_proto *tp;
 257	int err;
 258
 259	tp = kzalloc(sizeof(*tp), GFP_KERNEL);
 260	if (!tp)
 261		return ERR_PTR(-ENOBUFS);
 262
 263	tp->ops = tcf_proto_lookup_ops(kind, rtnl_held, extack);
 264	if (IS_ERR(tp->ops)) {
 265		err = PTR_ERR(tp->ops);
 266		goto errout;
 267	}
 268	tp->classify = tp->ops->classify;
 269	tp->protocol = protocol;
 270	tp->prio = prio;
 271	tp->chain = chain;
 272	spin_lock_init(&tp->lock);
 273	refcount_set(&tp->refcnt, 1);
 274
 275	err = tp->ops->init(tp);
 276	if (err) {
 277		module_put(tp->ops->owner);
 278		goto errout;
 279	}
 280	return tp;
 281
 282errout:
 283	kfree(tp);
 284	return ERR_PTR(err);
 285}
 286
 287static void tcf_proto_get(struct tcf_proto *tp)
 288{
 289	refcount_inc(&tp->refcnt);
 290}
 291
 292static void tcf_chain_put(struct tcf_chain *chain);
 293
 294static void tcf_proto_destroy(struct tcf_proto *tp, bool rtnl_held,
 295			      bool sig_destroy, struct netlink_ext_ack *extack)
 296{
 297	tp->ops->destroy(tp, rtnl_held, extack);
 298	if (sig_destroy)
 299		tcf_proto_signal_destroyed(tp->chain, tp);
 300	tcf_chain_put(tp->chain);
 301	module_put(tp->ops->owner);
 302	kfree_rcu(tp, rcu);
 303}
 304
 305static void tcf_proto_put(struct tcf_proto *tp, bool rtnl_held,
 306			  struct netlink_ext_ack *extack)
 307{
 308	if (refcount_dec_and_test(&tp->refcnt))
 309		tcf_proto_destroy(tp, rtnl_held, true, extack);
 310}
 311
 312static bool tcf_proto_check_delete(struct tcf_proto *tp)
 
 313{
 314	if (tp->ops->delete_empty)
 315		return tp->ops->delete_empty(tp);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 316
 317	tp->deleting = true;
 
 
 
 
 
 318	return tp->deleting;
 319}
 320
 321static void tcf_proto_mark_delete(struct tcf_proto *tp)
 322{
 323	spin_lock(&tp->lock);
 324	tp->deleting = true;
 325	spin_unlock(&tp->lock);
 326}
 327
 328static bool tcf_proto_is_deleting(struct tcf_proto *tp)
 329{
 330	bool deleting;
 331
 332	spin_lock(&tp->lock);
 333	deleting = tp->deleting;
 334	spin_unlock(&tp->lock);
 335
 336	return deleting;
 337}
 338
 339#define ASSERT_BLOCK_LOCKED(block)					\
 340	lockdep_assert_held(&(block)->lock)
 341
 342struct tcf_filter_chain_list_item {
 343	struct list_head list;
 344	tcf_chain_head_change_t *chain_head_change;
 345	void *chain_head_change_priv;
 346};
 347
 348static struct tcf_chain *tcf_chain_create(struct tcf_block *block,
 349					  u32 chain_index)
 350{
 351	struct tcf_chain *chain;
 352
 353	ASSERT_BLOCK_LOCKED(block);
 354
 355	chain = kzalloc(sizeof(*chain), GFP_KERNEL);
 356	if (!chain)
 357		return NULL;
 358	list_add_tail_rcu(&chain->list, &block->chain_list);
 359	mutex_init(&chain->filter_chain_lock);
 360	chain->block = block;
 361	chain->index = chain_index;
 362	chain->refcnt = 1;
 363	if (!chain->index)
 364		block->chain0.chain = chain;
 365	return chain;
 366}
 367
 368static void tcf_chain_head_change_item(struct tcf_filter_chain_list_item *item,
 369				       struct tcf_proto *tp_head)
 370{
 371	if (item->chain_head_change)
 372		item->chain_head_change(tp_head, item->chain_head_change_priv);
 373}
 374
 375static void tcf_chain0_head_change(struct tcf_chain *chain,
 376				   struct tcf_proto *tp_head)
 377{
 378	struct tcf_filter_chain_list_item *item;
 379	struct tcf_block *block = chain->block;
 380
 381	if (chain->index)
 382		return;
 383
 384	mutex_lock(&block->lock);
 385	list_for_each_entry(item, &block->chain0.filter_chain_list, list)
 386		tcf_chain_head_change_item(item, tp_head);
 387	mutex_unlock(&block->lock);
 388}
 389
 390/* Returns true if block can be safely freed. */
 391
 392static bool tcf_chain_detach(struct tcf_chain *chain)
 393{
 394	struct tcf_block *block = chain->block;
 395
 396	ASSERT_BLOCK_LOCKED(block);
 397
 398	list_del_rcu(&chain->list);
 399	if (!chain->index)
 400		block->chain0.chain = NULL;
 401
 402	if (list_empty(&block->chain_list) &&
 403	    refcount_read(&block->refcnt) == 0)
 404		return true;
 405
 406	return false;
 407}
 408
 409static void tcf_block_destroy(struct tcf_block *block)
 410{
 411	mutex_destroy(&block->lock);
 412	mutex_destroy(&block->proto_destroy_lock);
 413	kfree_rcu(block, rcu);
 414}
 415
 416static void tcf_chain_destroy(struct tcf_chain *chain, bool free_block)
 417{
 418	struct tcf_block *block = chain->block;
 419
 420	mutex_destroy(&chain->filter_chain_lock);
 421	kfree_rcu(chain, rcu);
 422	if (free_block)
 423		tcf_block_destroy(block);
 424}
 425
 426static void tcf_chain_hold(struct tcf_chain *chain)
 427{
 428	ASSERT_BLOCK_LOCKED(chain->block);
 429
 430	++chain->refcnt;
 431}
 432
 433static bool tcf_chain_held_by_acts_only(struct tcf_chain *chain)
 434{
 435	ASSERT_BLOCK_LOCKED(chain->block);
 436
 437	/* In case all the references are action references, this
 438	 * chain should not be shown to the user.
 439	 */
 440	return chain->refcnt == chain->action_refcnt;
 441}
 442
 443static struct tcf_chain *tcf_chain_lookup(struct tcf_block *block,
 444					  u32 chain_index)
 445{
 446	struct tcf_chain *chain;
 447
 448	ASSERT_BLOCK_LOCKED(block);
 449
 450	list_for_each_entry(chain, &block->chain_list, list) {
 451		if (chain->index == chain_index)
 452			return chain;
 453	}
 454	return NULL;
 455}
 456
 457#if IS_ENABLED(CONFIG_NET_TC_SKB_EXT)
 458static struct tcf_chain *tcf_chain_lookup_rcu(const struct tcf_block *block,
 459					      u32 chain_index)
 460{
 461	struct tcf_chain *chain;
 462
 463	list_for_each_entry_rcu(chain, &block->chain_list, list) {
 464		if (chain->index == chain_index)
 465			return chain;
 466	}
 467	return NULL;
 468}
 469#endif
 470
 471static int tc_chain_notify(struct tcf_chain *chain, struct sk_buff *oskb,
 472			   u32 seq, u16 flags, int event, bool unicast);
 473
 474static struct tcf_chain *__tcf_chain_get(struct tcf_block *block,
 475					 u32 chain_index, bool create,
 476					 bool by_act)
 477{
 478	struct tcf_chain *chain = NULL;
 479	bool is_first_reference;
 480
 481	mutex_lock(&block->lock);
 482	chain = tcf_chain_lookup(block, chain_index);
 483	if (chain) {
 484		tcf_chain_hold(chain);
 485	} else {
 486		if (!create)
 487			goto errout;
 488		chain = tcf_chain_create(block, chain_index);
 489		if (!chain)
 490			goto errout;
 491	}
 492
 493	if (by_act)
 494		++chain->action_refcnt;
 495	is_first_reference = chain->refcnt - chain->action_refcnt == 1;
 496	mutex_unlock(&block->lock);
 497
 498	/* Send notification only in case we got the first
 499	 * non-action reference. Until then, the chain acts only as
 500	 * a placeholder for actions pointing to it and user ought
 501	 * not know about them.
 502	 */
 503	if (is_first_reference && !by_act)
 504		tc_chain_notify(chain, NULL, 0, NLM_F_CREATE | NLM_F_EXCL,
 505				RTM_NEWCHAIN, false);
 506
 507	return chain;
 508
 509errout:
 510	mutex_unlock(&block->lock);
 511	return chain;
 512}
 513
 514static struct tcf_chain *tcf_chain_get(struct tcf_block *block, u32 chain_index,
 515				       bool create)
 516{
 517	return __tcf_chain_get(block, chain_index, create, false);
 518}
 519
 520struct tcf_chain *tcf_chain_get_by_act(struct tcf_block *block, u32 chain_index)
 521{
 522	return __tcf_chain_get(block, chain_index, true, true);
 523}
 524EXPORT_SYMBOL(tcf_chain_get_by_act);
 525
 526static void tc_chain_tmplt_del(const struct tcf_proto_ops *tmplt_ops,
 527			       void *tmplt_priv);
 528static int tc_chain_notify_delete(const struct tcf_proto_ops *tmplt_ops,
 529				  void *tmplt_priv, u32 chain_index,
 530				  struct tcf_block *block, struct sk_buff *oskb,
 531				  u32 seq, u16 flags, bool unicast);
 532
 533static void __tcf_chain_put(struct tcf_chain *chain, bool by_act,
 534			    bool explicitly_created)
 535{
 536	struct tcf_block *block = chain->block;
 537	const struct tcf_proto_ops *tmplt_ops;
 538	bool free_block = false;
 539	unsigned int refcnt;
 540	void *tmplt_priv;
 541
 542	mutex_lock(&block->lock);
 543	if (explicitly_created) {
 544		if (!chain->explicitly_created) {
 545			mutex_unlock(&block->lock);
 546			return;
 547		}
 548		chain->explicitly_created = false;
 549	}
 550
 551	if (by_act)
 552		chain->action_refcnt--;
 553
 554	/* tc_chain_notify_delete can't be called while holding block lock.
 555	 * However, when block is unlocked chain can be changed concurrently, so
 556	 * save these to temporary variables.
 557	 */
 558	refcnt = --chain->refcnt;
 559	tmplt_ops = chain->tmplt_ops;
 560	tmplt_priv = chain->tmplt_priv;
 561
 562	/* The last dropped non-action reference will trigger notification. */
 563	if (refcnt - chain->action_refcnt == 0 && !by_act) {
 564		tc_chain_notify_delete(tmplt_ops, tmplt_priv, chain->index,
 565				       block, NULL, 0, 0, false);
 566		/* Last reference to chain, no need to lock. */
 567		chain->flushing = false;
 568	}
 569
 570	if (refcnt == 0)
 571		free_block = tcf_chain_detach(chain);
 572	mutex_unlock(&block->lock);
 573
 574	if (refcnt == 0) {
 575		tc_chain_tmplt_del(tmplt_ops, tmplt_priv);
 576		tcf_chain_destroy(chain, free_block);
 577	}
 578}
 579
 580static void tcf_chain_put(struct tcf_chain *chain)
 581{
 582	__tcf_chain_put(chain, false, false);
 583}
 584
 585void tcf_chain_put_by_act(struct tcf_chain *chain)
 586{
 587	__tcf_chain_put(chain, true, false);
 588}
 589EXPORT_SYMBOL(tcf_chain_put_by_act);
 590
 591static void tcf_chain_put_explicitly_created(struct tcf_chain *chain)
 592{
 593	__tcf_chain_put(chain, false, true);
 594}
 595
 596static void tcf_chain_flush(struct tcf_chain *chain, bool rtnl_held)
 597{
 598	struct tcf_proto *tp, *tp_next;
 599
 600	mutex_lock(&chain->filter_chain_lock);
 601	tp = tcf_chain_dereference(chain->filter_chain, chain);
 602	while (tp) {
 603		tp_next = rcu_dereference_protected(tp->next, 1);
 604		tcf_proto_signal_destroying(chain, tp);
 605		tp = tp_next;
 606	}
 607	tp = tcf_chain_dereference(chain->filter_chain, chain);
 608	RCU_INIT_POINTER(chain->filter_chain, NULL);
 609	tcf_chain0_head_change(chain, NULL);
 610	chain->flushing = true;
 611	mutex_unlock(&chain->filter_chain_lock);
 612
 613	while (tp) {
 614		tp_next = rcu_dereference_protected(tp->next, 1);
 615		tcf_proto_put(tp, rtnl_held, NULL);
 616		tp = tp_next;
 617	}
 618}
 619
 620static int tcf_block_setup(struct tcf_block *block,
 621			   struct flow_block_offload *bo);
 622
 623static void tcf_block_offload_init(struct flow_block_offload *bo,
 624				   struct net_device *dev, struct Qdisc *sch,
 625				   enum flow_block_command command,
 626				   enum flow_block_binder_type binder_type,
 627				   struct flow_block *flow_block,
 628				   bool shared, struct netlink_ext_ack *extack)
 629{
 630	bo->net = dev_net(dev);
 631	bo->command = command;
 632	bo->binder_type = binder_type;
 633	bo->block = flow_block;
 634	bo->block_shared = shared;
 635	bo->extack = extack;
 636	bo->sch = sch;
 637	bo->cb_list_head = &flow_block->cb_list;
 638	INIT_LIST_HEAD(&bo->cb_list);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 639}
 640
 641static void tcf_block_unbind(struct tcf_block *block,
 642			     struct flow_block_offload *bo);
 
 
 
 
 
 
 
 643
 644static void tc_block_indr_cleanup(struct flow_block_cb *block_cb)
 
 
 
 
 645{
 646	struct tcf_block *block = block_cb->indr.data;
 647	struct net_device *dev = block_cb->indr.dev;
 648	struct Qdisc *sch = block_cb->indr.sch;
 649	struct netlink_ext_ack extack = {};
 650	struct flow_block_offload bo = {};
 
 
 
 
 651
 652	tcf_block_offload_init(&bo, dev, sch, FLOW_BLOCK_UNBIND,
 653			       block_cb->indr.binder_type,
 654			       &block->flow_block, tcf_block_shared(block),
 655			       &extack);
 656	rtnl_lock();
 657	down_write(&block->cb_lock);
 658	list_del(&block_cb->driver_list);
 659	list_move(&block_cb->list, &bo.cb_list);
 660	tcf_block_unbind(block, &bo);
 661	up_write(&block->cb_lock);
 662	rtnl_unlock();
 663}
 664
 665static bool tcf_block_offload_in_use(struct tcf_block *block)
 666{
 667	return atomic_read(&block->offloadcnt);
 668}
 669
 670static int tcf_block_offload_cmd(struct tcf_block *block,
 671				 struct net_device *dev, struct Qdisc *sch,
 672				 struct tcf_block_ext_info *ei,
 673				 enum flow_block_command command,
 674				 struct netlink_ext_ack *extack)
 675{
 676	struct flow_block_offload bo = {};
 
 677
 678	tcf_block_offload_init(&bo, dev, sch, command, ei->binder_type,
 679			       &block->flow_block, tcf_block_shared(block),
 680			       extack);
 
 
 
 
 681
 682	if (dev->netdev_ops->ndo_setup_tc) {
 683		int err;
 684
 685		err = dev->netdev_ops->ndo_setup_tc(dev, TC_SETUP_BLOCK, &bo);
 686		if (err < 0) {
 687			if (err != -EOPNOTSUPP)
 688				NL_SET_ERR_MSG(extack, "Driver ndo_setup_tc failed");
 689			return err;
 690		}
 691
 692		return tcf_block_setup(block, &bo);
 693	}
 694
 695	flow_indr_dev_setup_offload(dev, sch, TC_SETUP_BLOCK, block, &bo,
 696				    tc_block_indr_cleanup);
 697	tcf_block_setup(block, &bo);
 698
 699	return -EOPNOTSUPP;
 700}
 701
 702static int tcf_block_offload_bind(struct tcf_block *block, struct Qdisc *q,
 703				  struct tcf_block_ext_info *ei,
 704				  struct netlink_ext_ack *extack)
 705{
 706	struct net_device *dev = q->dev_queue->dev;
 707	int err;
 708
 709	down_write(&block->cb_lock);
 
 
 710
 711	/* If tc offload feature is disabled and the block we try to bind
 712	 * to already has some offloaded filters, forbid to bind.
 713	 */
 714	if (dev->netdev_ops->ndo_setup_tc &&
 715	    !tc_can_offload(dev) &&
 716	    tcf_block_offload_in_use(block)) {
 717		NL_SET_ERR_MSG(extack, "Bind to offloaded block failed as dev has offload disabled");
 718		err = -EOPNOTSUPP;
 719		goto err_unlock;
 720	}
 721
 722	err = tcf_block_offload_cmd(block, dev, q, ei, FLOW_BLOCK_BIND, extack);
 723	if (err == -EOPNOTSUPP)
 724		goto no_offload_dev_inc;
 725	if (err)
 726		goto err_unlock;
 727
 
 728	up_write(&block->cb_lock);
 729	return 0;
 730
 731no_offload_dev_inc:
 732	if (tcf_block_offload_in_use(block))
 
 733		goto err_unlock;
 734
 735	err = 0;
 736	block->nooffloaddevcnt++;
 
 737err_unlock:
 738	up_write(&block->cb_lock);
 739	return err;
 740}
 741
 742static void tcf_block_offload_unbind(struct tcf_block *block, struct Qdisc *q,
 743				     struct tcf_block_ext_info *ei)
 744{
 745	struct net_device *dev = q->dev_queue->dev;
 746	int err;
 747
 748	down_write(&block->cb_lock);
 749	err = tcf_block_offload_cmd(block, dev, q, ei, FLOW_BLOCK_UNBIND, NULL);
 
 
 
 
 750	if (err == -EOPNOTSUPP)
 751		goto no_offload_dev_dec;
 752	up_write(&block->cb_lock);
 753	return;
 754
 755no_offload_dev_dec:
 756	WARN_ON(block->nooffloaddevcnt-- == 0);
 757	up_write(&block->cb_lock);
 758}
 759
 760static int
 761tcf_chain0_head_change_cb_add(struct tcf_block *block,
 762			      struct tcf_block_ext_info *ei,
 763			      struct netlink_ext_ack *extack)
 764{
 765	struct tcf_filter_chain_list_item *item;
 766	struct tcf_chain *chain0;
 767
 768	item = kmalloc(sizeof(*item), GFP_KERNEL);
 769	if (!item) {
 770		NL_SET_ERR_MSG(extack, "Memory allocation for head change callback item failed");
 771		return -ENOMEM;
 772	}
 773	item->chain_head_change = ei->chain_head_change;
 774	item->chain_head_change_priv = ei->chain_head_change_priv;
 775
 776	mutex_lock(&block->lock);
 777	chain0 = block->chain0.chain;
 778	if (chain0)
 779		tcf_chain_hold(chain0);
 780	else
 781		list_add(&item->list, &block->chain0.filter_chain_list);
 782	mutex_unlock(&block->lock);
 783
 784	if (chain0) {
 785		struct tcf_proto *tp_head;
 786
 787		mutex_lock(&chain0->filter_chain_lock);
 788
 789		tp_head = tcf_chain_dereference(chain0->filter_chain, chain0);
 790		if (tp_head)
 791			tcf_chain_head_change_item(item, tp_head);
 792
 793		mutex_lock(&block->lock);
 794		list_add(&item->list, &block->chain0.filter_chain_list);
 795		mutex_unlock(&block->lock);
 796
 797		mutex_unlock(&chain0->filter_chain_lock);
 798		tcf_chain_put(chain0);
 799	}
 800
 801	return 0;
 802}
 803
 804static void
 805tcf_chain0_head_change_cb_del(struct tcf_block *block,
 806			      struct tcf_block_ext_info *ei)
 807{
 808	struct tcf_filter_chain_list_item *item;
 809
 810	mutex_lock(&block->lock);
 811	list_for_each_entry(item, &block->chain0.filter_chain_list, list) {
 812		if ((!ei->chain_head_change && !ei->chain_head_change_priv) ||
 813		    (item->chain_head_change == ei->chain_head_change &&
 814		     item->chain_head_change_priv == ei->chain_head_change_priv)) {
 815			if (block->chain0.chain)
 816				tcf_chain_head_change_item(item, NULL);
 817			list_del(&item->list);
 818			mutex_unlock(&block->lock);
 819
 820			kfree(item);
 821			return;
 822		}
 823	}
 824	mutex_unlock(&block->lock);
 825	WARN_ON(1);
 826}
 827
 828struct tcf_net {
 829	spinlock_t idr_lock; /* Protects idr */
 830	struct idr idr;
 831};
 832
 833static unsigned int tcf_net_id;
 834
 835static int tcf_block_insert(struct tcf_block *block, struct net *net,
 836			    struct netlink_ext_ack *extack)
 837{
 838	struct tcf_net *tn = net_generic(net, tcf_net_id);
 839	int err;
 840
 841	idr_preload(GFP_KERNEL);
 842	spin_lock(&tn->idr_lock);
 843	err = idr_alloc_u32(&tn->idr, block, &block->index, block->index,
 844			    GFP_NOWAIT);
 845	spin_unlock(&tn->idr_lock);
 846	idr_preload_end();
 847
 848	return err;
 849}
 850
 851static void tcf_block_remove(struct tcf_block *block, struct net *net)
 852{
 853	struct tcf_net *tn = net_generic(net, tcf_net_id);
 854
 855	spin_lock(&tn->idr_lock);
 856	idr_remove(&tn->idr, block->index);
 857	spin_unlock(&tn->idr_lock);
 858}
 859
 860static struct tcf_block *tcf_block_create(struct net *net, struct Qdisc *q,
 861					  u32 block_index,
 862					  struct netlink_ext_ack *extack)
 863{
 864	struct tcf_block *block;
 865
 866	block = kzalloc(sizeof(*block), GFP_KERNEL);
 867	if (!block) {
 868		NL_SET_ERR_MSG(extack, "Memory allocation for block failed");
 869		return ERR_PTR(-ENOMEM);
 870	}
 871	mutex_init(&block->lock);
 872	mutex_init(&block->proto_destroy_lock);
 873	init_rwsem(&block->cb_lock);
 874	flow_block_init(&block->flow_block);
 875	INIT_LIST_HEAD(&block->chain_list);
 876	INIT_LIST_HEAD(&block->owner_list);
 877	INIT_LIST_HEAD(&block->chain0.filter_chain_list);
 878
 879	refcount_set(&block->refcnt, 1);
 880	block->net = net;
 881	block->index = block_index;
 882
 883	/* Don't store q pointer for blocks which are shared */
 884	if (!tcf_block_shared(block))
 885		block->q = q;
 886	return block;
 887}
 888
 889static struct tcf_block *tcf_block_lookup(struct net *net, u32 block_index)
 890{
 891	struct tcf_net *tn = net_generic(net, tcf_net_id);
 892
 893	return idr_find(&tn->idr, block_index);
 894}
 895
 896static struct tcf_block *tcf_block_refcnt_get(struct net *net, u32 block_index)
 897{
 898	struct tcf_block *block;
 899
 900	rcu_read_lock();
 901	block = tcf_block_lookup(net, block_index);
 902	if (block && !refcount_inc_not_zero(&block->refcnt))
 903		block = NULL;
 904	rcu_read_unlock();
 905
 906	return block;
 907}
 908
 909static struct tcf_chain *
 910__tcf_get_next_chain(struct tcf_block *block, struct tcf_chain *chain)
 911{
 912	mutex_lock(&block->lock);
 913	if (chain)
 914		chain = list_is_last(&chain->list, &block->chain_list) ?
 915			NULL : list_next_entry(chain, list);
 916	else
 917		chain = list_first_entry_or_null(&block->chain_list,
 918						 struct tcf_chain, list);
 919
 920	/* skip all action-only chains */
 921	while (chain && tcf_chain_held_by_acts_only(chain))
 922		chain = list_is_last(&chain->list, &block->chain_list) ?
 923			NULL : list_next_entry(chain, list);
 924
 925	if (chain)
 926		tcf_chain_hold(chain);
 927	mutex_unlock(&block->lock);
 928
 929	return chain;
 930}
 931
 932/* Function to be used by all clients that want to iterate over all chains on
 933 * block. It properly obtains block->lock and takes reference to chain before
 934 * returning it. Users of this function must be tolerant to concurrent chain
 935 * insertion/deletion or ensure that no concurrent chain modification is
 936 * possible. Note that all netlink dump callbacks cannot guarantee to provide
 937 * consistent dump because rtnl lock is released each time skb is filled with
 938 * data and sent to user-space.
 939 */
 940
 941struct tcf_chain *
 942tcf_get_next_chain(struct tcf_block *block, struct tcf_chain *chain)
 943{
 944	struct tcf_chain *chain_next = __tcf_get_next_chain(block, chain);
 945
 946	if (chain)
 947		tcf_chain_put(chain);
 948
 949	return chain_next;
 950}
 951EXPORT_SYMBOL(tcf_get_next_chain);
 952
 953static struct tcf_proto *
 954__tcf_get_next_proto(struct tcf_chain *chain, struct tcf_proto *tp)
 955{
 956	u32 prio = 0;
 957
 958	ASSERT_RTNL();
 959	mutex_lock(&chain->filter_chain_lock);
 960
 961	if (!tp) {
 962		tp = tcf_chain_dereference(chain->filter_chain, chain);
 963	} else if (tcf_proto_is_deleting(tp)) {
 964		/* 'deleting' flag is set and chain->filter_chain_lock was
 965		 * unlocked, which means next pointer could be invalid. Restart
 966		 * search.
 967		 */
 968		prio = tp->prio + 1;
 969		tp = tcf_chain_dereference(chain->filter_chain, chain);
 970
 971		for (; tp; tp = tcf_chain_dereference(tp->next, chain))
 972			if (!tp->deleting && tp->prio >= prio)
 973				break;
 974	} else {
 975		tp = tcf_chain_dereference(tp->next, chain);
 976	}
 977
 978	if (tp)
 979		tcf_proto_get(tp);
 980
 981	mutex_unlock(&chain->filter_chain_lock);
 982
 983	return tp;
 984}
 985
 986/* Function to be used by all clients that want to iterate over all tp's on
 987 * chain. Users of this function must be tolerant to concurrent tp
 988 * insertion/deletion or ensure that no concurrent chain modification is
 989 * possible. Note that all netlink dump callbacks cannot guarantee to provide
 990 * consistent dump because rtnl lock is released each time skb is filled with
 991 * data and sent to user-space.
 992 */
 993
 994struct tcf_proto *
 995tcf_get_next_proto(struct tcf_chain *chain, struct tcf_proto *tp)
 
 996{
 997	struct tcf_proto *tp_next = __tcf_get_next_proto(chain, tp);
 998
 999	if (tp)
1000		tcf_proto_put(tp, true, NULL);
1001
1002	return tp_next;
1003}
1004EXPORT_SYMBOL(tcf_get_next_proto);
1005
1006static void tcf_block_flush_all_chains(struct tcf_block *block, bool rtnl_held)
1007{
1008	struct tcf_chain *chain;
1009
1010	/* Last reference to block. At this point chains cannot be added or
1011	 * removed concurrently.
1012	 */
1013	for (chain = tcf_get_next_chain(block, NULL);
1014	     chain;
1015	     chain = tcf_get_next_chain(block, chain)) {
1016		tcf_chain_put_explicitly_created(chain);
1017		tcf_chain_flush(chain, rtnl_held);
1018	}
1019}
1020
1021/* Lookup Qdisc and increments its reference counter.
1022 * Set parent, if necessary.
1023 */
1024
1025static int __tcf_qdisc_find(struct net *net, struct Qdisc **q,
1026			    u32 *parent, int ifindex, bool rtnl_held,
1027			    struct netlink_ext_ack *extack)
1028{
1029	const struct Qdisc_class_ops *cops;
1030	struct net_device *dev;
1031	int err = 0;
1032
1033	if (ifindex == TCM_IFINDEX_MAGIC_BLOCK)
1034		return 0;
1035
1036	rcu_read_lock();
1037
1038	/* Find link */
1039	dev = dev_get_by_index_rcu(net, ifindex);
1040	if (!dev) {
1041		rcu_read_unlock();
1042		return -ENODEV;
1043	}
1044
1045	/* Find qdisc */
1046	if (!*parent) {
1047		*q = dev->qdisc;
1048		*parent = (*q)->handle;
1049	} else {
1050		*q = qdisc_lookup_rcu(dev, TC_H_MAJ(*parent));
1051		if (!*q) {
1052			NL_SET_ERR_MSG(extack, "Parent Qdisc doesn't exists");
1053			err = -EINVAL;
1054			goto errout_rcu;
1055		}
1056	}
1057
1058	*q = qdisc_refcount_inc_nz(*q);
1059	if (!*q) {
1060		NL_SET_ERR_MSG(extack, "Parent Qdisc doesn't exists");
1061		err = -EINVAL;
1062		goto errout_rcu;
1063	}
1064
1065	/* Is it classful? */
1066	cops = (*q)->ops->cl_ops;
1067	if (!cops) {
1068		NL_SET_ERR_MSG(extack, "Qdisc not classful");
1069		err = -EINVAL;
1070		goto errout_qdisc;
1071	}
1072
1073	if (!cops->tcf_block) {
1074		NL_SET_ERR_MSG(extack, "Class doesn't support blocks");
1075		err = -EOPNOTSUPP;
1076		goto errout_qdisc;
1077	}
1078
1079errout_rcu:
1080	/* At this point we know that qdisc is not noop_qdisc,
1081	 * which means that qdisc holds a reference to net_device
1082	 * and we hold a reference to qdisc, so it is safe to release
1083	 * rcu read lock.
1084	 */
1085	rcu_read_unlock();
1086	return err;
1087
1088errout_qdisc:
1089	rcu_read_unlock();
1090
1091	if (rtnl_held)
1092		qdisc_put(*q);
1093	else
1094		qdisc_put_unlocked(*q);
1095	*q = NULL;
1096
1097	return err;
1098}
1099
1100static int __tcf_qdisc_cl_find(struct Qdisc *q, u32 parent, unsigned long *cl,
1101			       int ifindex, struct netlink_ext_ack *extack)
1102{
1103	if (ifindex == TCM_IFINDEX_MAGIC_BLOCK)
1104		return 0;
1105
1106	/* Do we search for filter, attached to class? */
1107	if (TC_H_MIN(parent)) {
1108		const struct Qdisc_class_ops *cops = q->ops->cl_ops;
1109
1110		*cl = cops->find(q, parent);
1111		if (*cl == 0) {
1112			NL_SET_ERR_MSG(extack, "Specified class doesn't exist");
1113			return -ENOENT;
1114		}
1115	}
1116
1117	return 0;
1118}
1119
1120static struct tcf_block *__tcf_block_find(struct net *net, struct Qdisc *q,
1121					  unsigned long cl, int ifindex,
1122					  u32 block_index,
1123					  struct netlink_ext_ack *extack)
1124{
1125	struct tcf_block *block;
1126
1127	if (ifindex == TCM_IFINDEX_MAGIC_BLOCK) {
1128		block = tcf_block_refcnt_get(net, block_index);
1129		if (!block) {
1130			NL_SET_ERR_MSG(extack, "Block of given index was not found");
1131			return ERR_PTR(-EINVAL);
1132		}
1133	} else {
1134		const struct Qdisc_class_ops *cops = q->ops->cl_ops;
1135
1136		block = cops->tcf_block(q, cl, extack);
1137		if (!block)
1138			return ERR_PTR(-EINVAL);
1139
1140		if (tcf_block_shared(block)) {
1141			NL_SET_ERR_MSG(extack, "This filter block is shared. Please use the block index to manipulate the filters");
1142			return ERR_PTR(-EOPNOTSUPP);
1143		}
1144
1145		/* Always take reference to block in order to support execution
1146		 * of rules update path of cls API without rtnl lock. Caller
1147		 * must release block when it is finished using it. 'if' block
1148		 * of this conditional obtain reference to block by calling
1149		 * tcf_block_refcnt_get().
1150		 */
1151		refcount_inc(&block->refcnt);
1152	}
1153
1154	return block;
1155}
1156
1157static void __tcf_block_put(struct tcf_block *block, struct Qdisc *q,
1158			    struct tcf_block_ext_info *ei, bool rtnl_held)
1159{
1160	if (refcount_dec_and_mutex_lock(&block->refcnt, &block->lock)) {
1161		/* Flushing/putting all chains will cause the block to be
1162		 * deallocated when last chain is freed. However, if chain_list
1163		 * is empty, block has to be manually deallocated. After block
1164		 * reference counter reached 0, it is no longer possible to
1165		 * increment it or add new chains to block.
1166		 */
1167		bool free_block = list_empty(&block->chain_list);
1168
1169		mutex_unlock(&block->lock);
1170		if (tcf_block_shared(block))
1171			tcf_block_remove(block, block->net);
1172
1173		if (q)
1174			tcf_block_offload_unbind(block, q, ei);
1175
1176		if (free_block)
1177			tcf_block_destroy(block);
1178		else
1179			tcf_block_flush_all_chains(block, rtnl_held);
1180	} else if (q) {
1181		tcf_block_offload_unbind(block, q, ei);
1182	}
1183}
1184
1185static void tcf_block_refcnt_put(struct tcf_block *block, bool rtnl_held)
1186{
1187	__tcf_block_put(block, NULL, NULL, rtnl_held);
1188}
1189
1190/* Find tcf block.
1191 * Set q, parent, cl when appropriate.
1192 */
1193
1194static struct tcf_block *tcf_block_find(struct net *net, struct Qdisc **q,
1195					u32 *parent, unsigned long *cl,
1196					int ifindex, u32 block_index,
1197					struct netlink_ext_ack *extack)
1198{
1199	struct tcf_block *block;
1200	int err = 0;
1201
1202	ASSERT_RTNL();
1203
1204	err = __tcf_qdisc_find(net, q, parent, ifindex, true, extack);
1205	if (err)
1206		goto errout;
1207
1208	err = __tcf_qdisc_cl_find(*q, *parent, cl, ifindex, extack);
1209	if (err)
1210		goto errout_qdisc;
1211
1212	block = __tcf_block_find(net, *q, *cl, ifindex, block_index, extack);
1213	if (IS_ERR(block)) {
1214		err = PTR_ERR(block);
1215		goto errout_qdisc;
1216	}
1217
1218	return block;
1219
1220errout_qdisc:
1221	if (*q)
1222		qdisc_put(*q);
1223errout:
1224	*q = NULL;
1225	return ERR_PTR(err);
1226}
1227
1228static void tcf_block_release(struct Qdisc *q, struct tcf_block *block,
1229			      bool rtnl_held)
1230{
1231	if (!IS_ERR_OR_NULL(block))
1232		tcf_block_refcnt_put(block, rtnl_held);
1233
1234	if (q) {
1235		if (rtnl_held)
1236			qdisc_put(q);
1237		else
1238			qdisc_put_unlocked(q);
1239	}
1240}
1241
1242struct tcf_block_owner_item {
1243	struct list_head list;
1244	struct Qdisc *q;
1245	enum flow_block_binder_type binder_type;
1246};
1247
1248static void
1249tcf_block_owner_netif_keep_dst(struct tcf_block *block,
1250			       struct Qdisc *q,
1251			       enum flow_block_binder_type binder_type)
1252{
1253	if (block->keep_dst &&
1254	    binder_type != FLOW_BLOCK_BINDER_TYPE_CLSACT_INGRESS &&
1255	    binder_type != FLOW_BLOCK_BINDER_TYPE_CLSACT_EGRESS)
1256		netif_keep_dst(qdisc_dev(q));
1257}
1258
1259void tcf_block_netif_keep_dst(struct tcf_block *block)
1260{
1261	struct tcf_block_owner_item *item;
1262
1263	block->keep_dst = true;
1264	list_for_each_entry(item, &block->owner_list, list)
1265		tcf_block_owner_netif_keep_dst(block, item->q,
1266					       item->binder_type);
1267}
1268EXPORT_SYMBOL(tcf_block_netif_keep_dst);
1269
1270static int tcf_block_owner_add(struct tcf_block *block,
1271			       struct Qdisc *q,
1272			       enum flow_block_binder_type binder_type)
1273{
1274	struct tcf_block_owner_item *item;
1275
1276	item = kmalloc(sizeof(*item), GFP_KERNEL);
1277	if (!item)
1278		return -ENOMEM;
1279	item->q = q;
1280	item->binder_type = binder_type;
1281	list_add(&item->list, &block->owner_list);
1282	return 0;
1283}
1284
1285static void tcf_block_owner_del(struct tcf_block *block,
1286				struct Qdisc *q,
1287				enum flow_block_binder_type binder_type)
1288{
1289	struct tcf_block_owner_item *item;
1290
1291	list_for_each_entry(item, &block->owner_list, list) {
1292		if (item->q == q && item->binder_type == binder_type) {
1293			list_del(&item->list);
1294			kfree(item);
1295			return;
1296		}
1297	}
1298	WARN_ON(1);
1299}
1300
1301int tcf_block_get_ext(struct tcf_block **p_block, struct Qdisc *q,
1302		      struct tcf_block_ext_info *ei,
1303		      struct netlink_ext_ack *extack)
1304{
1305	struct net *net = qdisc_net(q);
1306	struct tcf_block *block = NULL;
1307	int err;
1308
1309	if (ei->block_index)
1310		/* block_index not 0 means the shared block is requested */
1311		block = tcf_block_refcnt_get(net, ei->block_index);
1312
1313	if (!block) {
1314		block = tcf_block_create(net, q, ei->block_index, extack);
1315		if (IS_ERR(block))
1316			return PTR_ERR(block);
1317		if (tcf_block_shared(block)) {
1318			err = tcf_block_insert(block, net, extack);
1319			if (err)
1320				goto err_block_insert;
1321		}
1322	}
1323
1324	err = tcf_block_owner_add(block, q, ei->binder_type);
1325	if (err)
1326		goto err_block_owner_add;
1327
1328	tcf_block_owner_netif_keep_dst(block, q, ei->binder_type);
1329
1330	err = tcf_chain0_head_change_cb_add(block, ei, extack);
1331	if (err)
1332		goto err_chain0_head_change_cb_add;
1333
1334	err = tcf_block_offload_bind(block, q, ei, extack);
1335	if (err)
1336		goto err_block_offload_bind;
1337
1338	*p_block = block;
1339	return 0;
1340
1341err_block_offload_bind:
1342	tcf_chain0_head_change_cb_del(block, ei);
1343err_chain0_head_change_cb_add:
1344	tcf_block_owner_del(block, q, ei->binder_type);
1345err_block_owner_add:
1346err_block_insert:
1347	tcf_block_refcnt_put(block, true);
1348	return err;
1349}
1350EXPORT_SYMBOL(tcf_block_get_ext);
1351
1352static void tcf_chain_head_change_dflt(struct tcf_proto *tp_head, void *priv)
1353{
1354	struct tcf_proto __rcu **p_filter_chain = priv;
1355
1356	rcu_assign_pointer(*p_filter_chain, tp_head);
1357}
1358
1359int tcf_block_get(struct tcf_block **p_block,
1360		  struct tcf_proto __rcu **p_filter_chain, struct Qdisc *q,
1361		  struct netlink_ext_ack *extack)
1362{
1363	struct tcf_block_ext_info ei = {
1364		.chain_head_change = tcf_chain_head_change_dflt,
1365		.chain_head_change_priv = p_filter_chain,
1366	};
1367
1368	WARN_ON(!p_filter_chain);
1369	return tcf_block_get_ext(p_block, q, &ei, extack);
1370}
1371EXPORT_SYMBOL(tcf_block_get);
1372
1373/* XXX: Standalone actions are not allowed to jump to any chain, and bound
1374 * actions should be all removed after flushing.
1375 */
1376void tcf_block_put_ext(struct tcf_block *block, struct Qdisc *q,
1377		       struct tcf_block_ext_info *ei)
1378{
1379	if (!block)
1380		return;
1381	tcf_chain0_head_change_cb_del(block, ei);
1382	tcf_block_owner_del(block, q, ei->binder_type);
1383
1384	__tcf_block_put(block, q, ei, true);
1385}
1386EXPORT_SYMBOL(tcf_block_put_ext);
1387
1388void tcf_block_put(struct tcf_block *block)
1389{
1390	struct tcf_block_ext_info ei = {0, };
1391
1392	if (!block)
1393		return;
1394	tcf_block_put_ext(block, block->q, &ei);
1395}
1396
1397EXPORT_SYMBOL(tcf_block_put);
1398
1399static int
1400tcf_block_playback_offloads(struct tcf_block *block, flow_setup_cb_t *cb,
1401			    void *cb_priv, bool add, bool offload_in_use,
1402			    struct netlink_ext_ack *extack)
1403{
1404	struct tcf_chain *chain, *chain_prev;
1405	struct tcf_proto *tp, *tp_prev;
1406	int err;
1407
1408	lockdep_assert_held(&block->cb_lock);
1409
1410	for (chain = __tcf_get_next_chain(block, NULL);
1411	     chain;
1412	     chain_prev = chain,
1413		     chain = __tcf_get_next_chain(block, chain),
1414		     tcf_chain_put(chain_prev)) {
1415		for (tp = __tcf_get_next_proto(chain, NULL); tp;
1416		     tp_prev = tp,
1417			     tp = __tcf_get_next_proto(chain, tp),
1418			     tcf_proto_put(tp_prev, true, NULL)) {
1419			if (tp->ops->reoffload) {
1420				err = tp->ops->reoffload(tp, add, cb, cb_priv,
1421							 extack);
1422				if (err && add)
1423					goto err_playback_remove;
1424			} else if (add && offload_in_use) {
1425				err = -EOPNOTSUPP;
1426				NL_SET_ERR_MSG(extack, "Filter HW offload failed - classifier without re-offloading support");
1427				goto err_playback_remove;
1428			}
1429		}
1430	}
1431
1432	return 0;
1433
1434err_playback_remove:
1435	tcf_proto_put(tp, true, NULL);
1436	tcf_chain_put(chain);
1437	tcf_block_playback_offloads(block, cb, cb_priv, false, offload_in_use,
1438				    extack);
1439	return err;
1440}
1441
1442static int tcf_block_bind(struct tcf_block *block,
1443			  struct flow_block_offload *bo)
1444{
1445	struct flow_block_cb *block_cb, *next;
1446	int err, i = 0;
1447
1448	lockdep_assert_held(&block->cb_lock);
1449
1450	list_for_each_entry(block_cb, &bo->cb_list, list) {
1451		err = tcf_block_playback_offloads(block, block_cb->cb,
1452						  block_cb->cb_priv, true,
1453						  tcf_block_offload_in_use(block),
1454						  bo->extack);
1455		if (err)
1456			goto err_unroll;
1457		if (!bo->unlocked_driver_cb)
1458			block->lockeddevcnt++;
1459
1460		i++;
1461	}
1462	list_splice(&bo->cb_list, &block->flow_block.cb_list);
1463
1464	return 0;
1465
1466err_unroll:
1467	list_for_each_entry_safe(block_cb, next, &bo->cb_list, list) {
1468		if (i-- > 0) {
1469			list_del(&block_cb->list);
1470			tcf_block_playback_offloads(block, block_cb->cb,
1471						    block_cb->cb_priv, false,
1472						    tcf_block_offload_in_use(block),
1473						    NULL);
1474			if (!bo->unlocked_driver_cb)
1475				block->lockeddevcnt--;
1476		}
1477		flow_block_cb_free(block_cb);
1478	}
1479
1480	return err;
1481}
1482
1483static void tcf_block_unbind(struct tcf_block *block,
1484			     struct flow_block_offload *bo)
1485{
1486	struct flow_block_cb *block_cb, *next;
1487
1488	lockdep_assert_held(&block->cb_lock);
1489
1490	list_for_each_entry_safe(block_cb, next, &bo->cb_list, list) {
1491		tcf_block_playback_offloads(block, block_cb->cb,
1492					    block_cb->cb_priv, false,
1493					    tcf_block_offload_in_use(block),
1494					    NULL);
1495		list_del(&block_cb->list);
1496		flow_block_cb_free(block_cb);
1497		if (!bo->unlocked_driver_cb)
1498			block->lockeddevcnt--;
1499	}
1500}
1501
1502static int tcf_block_setup(struct tcf_block *block,
1503			   struct flow_block_offload *bo)
1504{
1505	int err;
1506
1507	switch (bo->command) {
1508	case FLOW_BLOCK_BIND:
1509		err = tcf_block_bind(block, bo);
1510		break;
1511	case FLOW_BLOCK_UNBIND:
1512		err = 0;
1513		tcf_block_unbind(block, bo);
1514		break;
1515	default:
1516		WARN_ON_ONCE(1);
1517		err = -EOPNOTSUPP;
1518	}
1519
1520	return err;
1521}
1522
1523/* Main classifier routine: scans classifier chain attached
1524 * to this qdisc, (optionally) tests for protocol and asks
1525 * specific classifiers.
1526 */
1527static inline int __tcf_classify(struct sk_buff *skb,
1528				 const struct tcf_proto *tp,
1529				 const struct tcf_proto *orig_tp,
1530				 struct tcf_result *res,
1531				 bool compat_mode,
1532				 u32 *last_executed_chain)
1533{
1534#ifdef CONFIG_NET_CLS_ACT
1535	const int max_reclassify_loop = 16;
 
1536	const struct tcf_proto *first_tp;
1537	int limit = 0;
1538
1539reclassify:
1540#endif
1541	for (; tp; tp = rcu_dereference_bh(tp->next)) {
1542		__be16 protocol = skb_protocol(skb, false);
1543		int err;
1544
1545		if (tp->protocol != protocol &&
1546		    tp->protocol != htons(ETH_P_ALL))
1547			continue;
1548
1549		err = tp->classify(skb, tp, res);
1550#ifdef CONFIG_NET_CLS_ACT
1551		if (unlikely(err == TC_ACT_RECLASSIFY && !compat_mode)) {
1552			first_tp = orig_tp;
1553			*last_executed_chain = first_tp->chain->index;
1554			goto reset;
1555		} else if (unlikely(TC_ACT_EXT_CMP(err, TC_ACT_GOTO_CHAIN))) {
1556			first_tp = res->goto_tp;
1557			*last_executed_chain = err & TC_ACT_EXT_VAL_MASK;
 
 
 
 
 
 
 
 
 
 
 
1558			goto reset;
1559		}
1560#endif
1561		if (err >= 0)
1562			return err;
1563	}
1564
1565	return TC_ACT_UNSPEC; /* signal: continue lookup */
1566#ifdef CONFIG_NET_CLS_ACT
1567reset:
1568	if (unlikely(limit++ >= max_reclassify_loop)) {
1569		net_notice_ratelimited("%u: reclassify loop, rule prio %u, protocol %02x\n",
1570				       tp->chain->block->index,
1571				       tp->prio & 0xffff,
1572				       ntohs(tp->protocol));
1573		return TC_ACT_SHOT;
1574	}
1575
1576	tp = first_tp;
1577	goto reclassify;
1578#endif
1579}
1580
1581int tcf_classify(struct sk_buff *skb, const struct tcf_proto *tp,
1582		 struct tcf_result *res, bool compat_mode)
1583{
1584	u32 last_executed_chain = 0;
1585
1586	return __tcf_classify(skb, tp, tp, res, compat_mode,
1587			      &last_executed_chain);
1588}
1589EXPORT_SYMBOL(tcf_classify);
1590
1591int tcf_classify_ingress(struct sk_buff *skb,
1592			 const struct tcf_block *ingress_block,
1593			 const struct tcf_proto *tp,
1594			 struct tcf_result *res, bool compat_mode)
1595{
1596#if !IS_ENABLED(CONFIG_NET_TC_SKB_EXT)
1597	u32 last_executed_chain = 0;
1598
1599	return __tcf_classify(skb, tp, tp, res, compat_mode,
1600			      &last_executed_chain);
1601#else
1602	u32 last_executed_chain = tp ? tp->chain->index : 0;
1603	const struct tcf_proto *orig_tp = tp;
1604	struct tc_skb_ext *ext;
1605	int ret;
1606
1607	ext = skb_ext_find(skb, TC_SKB_EXT);
1608
1609	if (ext && ext->chain) {
1610		struct tcf_chain *fchain;
1611
1612		fchain = tcf_chain_lookup_rcu(ingress_block, ext->chain);
1613		if (!fchain)
1614			return TC_ACT_SHOT;
1615
1616		/* Consume, so cloned/redirect skbs won't inherit ext */
1617		skb_ext_del(skb, TC_SKB_EXT);
1618
1619		tp = rcu_dereference_bh(fchain->filter_chain);
1620		last_executed_chain = fchain->index;
1621	}
1622
1623	ret = __tcf_classify(skb, tp, orig_tp, res, compat_mode,
1624			     &last_executed_chain);
1625
1626	/* If we missed on some chain */
1627	if (ret == TC_ACT_UNSPEC && last_executed_chain) {
1628		ext = tc_skb_ext_alloc(skb);
1629		if (WARN_ON_ONCE(!ext))
1630			return TC_ACT_SHOT;
1631		ext->chain = last_executed_chain;
1632		ext->mru = qdisc_skb_cb(skb)->mru;
1633		ext->post_ct = qdisc_skb_cb(skb)->post_ct;
1634	}
1635
1636	return ret;
1637#endif
1638}
1639EXPORT_SYMBOL(tcf_classify_ingress);
1640
1641struct tcf_chain_info {
1642	struct tcf_proto __rcu **pprev;
1643	struct tcf_proto __rcu *next;
1644};
1645
1646static struct tcf_proto *tcf_chain_tp_prev(struct tcf_chain *chain,
1647					   struct tcf_chain_info *chain_info)
1648{
1649	return tcf_chain_dereference(*chain_info->pprev, chain);
1650}
1651
1652static int tcf_chain_tp_insert(struct tcf_chain *chain,
1653			       struct tcf_chain_info *chain_info,
1654			       struct tcf_proto *tp)
1655{
1656	if (chain->flushing)
1657		return -EAGAIN;
1658
1659	if (*chain_info->pprev == chain->filter_chain)
1660		tcf_chain0_head_change(chain, tp);
1661	tcf_proto_get(tp);
1662	RCU_INIT_POINTER(tp->next, tcf_chain_tp_prev(chain, chain_info));
1663	rcu_assign_pointer(*chain_info->pprev, tp);
1664
1665	return 0;
1666}
1667
1668static void tcf_chain_tp_remove(struct tcf_chain *chain,
1669				struct tcf_chain_info *chain_info,
1670				struct tcf_proto *tp)
1671{
1672	struct tcf_proto *next = tcf_chain_dereference(chain_info->next, chain);
1673
1674	tcf_proto_mark_delete(tp);
1675	if (tp == chain->filter_chain)
1676		tcf_chain0_head_change(chain, next);
1677	RCU_INIT_POINTER(*chain_info->pprev, next);
1678}
1679
1680static struct tcf_proto *tcf_chain_tp_find(struct tcf_chain *chain,
1681					   struct tcf_chain_info *chain_info,
1682					   u32 protocol, u32 prio,
1683					   bool prio_allocate);
1684
1685/* Try to insert new proto.
1686 * If proto with specified priority already exists, free new proto
1687 * and return existing one.
1688 */
1689
1690static struct tcf_proto *tcf_chain_tp_insert_unique(struct tcf_chain *chain,
1691						    struct tcf_proto *tp_new,
1692						    u32 protocol, u32 prio,
1693						    bool rtnl_held)
1694{
1695	struct tcf_chain_info chain_info;
1696	struct tcf_proto *tp;
1697	int err = 0;
1698
1699	mutex_lock(&chain->filter_chain_lock);
1700
1701	if (tcf_proto_exists_destroying(chain, tp_new)) {
1702		mutex_unlock(&chain->filter_chain_lock);
1703		tcf_proto_destroy(tp_new, rtnl_held, false, NULL);
1704		return ERR_PTR(-EAGAIN);
1705	}
1706
1707	tp = tcf_chain_tp_find(chain, &chain_info,
1708			       protocol, prio, false);
1709	if (!tp)
1710		err = tcf_chain_tp_insert(chain, &chain_info, tp_new);
1711	mutex_unlock(&chain->filter_chain_lock);
1712
1713	if (tp) {
1714		tcf_proto_destroy(tp_new, rtnl_held, false, NULL);
1715		tp_new = tp;
1716	} else if (err) {
1717		tcf_proto_destroy(tp_new, rtnl_held, false, NULL);
1718		tp_new = ERR_PTR(err);
1719	}
1720
1721	return tp_new;
1722}
1723
1724static void tcf_chain_tp_delete_empty(struct tcf_chain *chain,
1725				      struct tcf_proto *tp, bool rtnl_held,
1726				      struct netlink_ext_ack *extack)
1727{
1728	struct tcf_chain_info chain_info;
1729	struct tcf_proto *tp_iter;
1730	struct tcf_proto **pprev;
1731	struct tcf_proto *next;
1732
1733	mutex_lock(&chain->filter_chain_lock);
1734
1735	/* Atomically find and remove tp from chain. */
1736	for (pprev = &chain->filter_chain;
1737	     (tp_iter = tcf_chain_dereference(*pprev, chain));
1738	     pprev = &tp_iter->next) {
1739		if (tp_iter == tp) {
1740			chain_info.pprev = pprev;
1741			chain_info.next = tp_iter->next;
1742			WARN_ON(tp_iter->deleting);
1743			break;
1744		}
1745	}
1746	/* Verify that tp still exists and no new filters were inserted
1747	 * concurrently.
1748	 * Mark tp for deletion if it is empty.
1749	 */
1750	if (!tp_iter || !tcf_proto_check_delete(tp)) {
1751		mutex_unlock(&chain->filter_chain_lock);
1752		return;
1753	}
1754
1755	tcf_proto_signal_destroying(chain, tp);
1756	next = tcf_chain_dereference(chain_info.next, chain);
1757	if (tp == chain->filter_chain)
1758		tcf_chain0_head_change(chain, next);
1759	RCU_INIT_POINTER(*chain_info.pprev, next);
1760	mutex_unlock(&chain->filter_chain_lock);
1761
1762	tcf_proto_put(tp, rtnl_held, extack);
1763}
1764
1765static struct tcf_proto *tcf_chain_tp_find(struct tcf_chain *chain,
1766					   struct tcf_chain_info *chain_info,
1767					   u32 protocol, u32 prio,
1768					   bool prio_allocate)
1769{
1770	struct tcf_proto **pprev;
1771	struct tcf_proto *tp;
1772
1773	/* Check the chain for existence of proto-tcf with this priority */
1774	for (pprev = &chain->filter_chain;
1775	     (tp = tcf_chain_dereference(*pprev, chain));
1776	     pprev = &tp->next) {
1777		if (tp->prio >= prio) {
1778			if (tp->prio == prio) {
1779				if (prio_allocate ||
1780				    (tp->protocol != protocol && protocol))
1781					return ERR_PTR(-EINVAL);
1782			} else {
1783				tp = NULL;
1784			}
1785			break;
1786		}
1787	}
1788	chain_info->pprev = pprev;
1789	if (tp) {
1790		chain_info->next = tp->next;
1791		tcf_proto_get(tp);
1792	} else {
1793		chain_info->next = NULL;
1794	}
1795	return tp;
1796}
1797
1798static int tcf_fill_node(struct net *net, struct sk_buff *skb,
1799			 struct tcf_proto *tp, struct tcf_block *block,
1800			 struct Qdisc *q, u32 parent, void *fh,
1801			 u32 portid, u32 seq, u16 flags, int event,
1802			 bool terse_dump, bool rtnl_held)
1803{
1804	struct tcmsg *tcm;
1805	struct nlmsghdr  *nlh;
1806	unsigned char *b = skb_tail_pointer(skb);
1807
1808	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*tcm), flags);
1809	if (!nlh)
1810		goto out_nlmsg_trim;
1811	tcm = nlmsg_data(nlh);
1812	tcm->tcm_family = AF_UNSPEC;
1813	tcm->tcm__pad1 = 0;
1814	tcm->tcm__pad2 = 0;
1815	if (q) {
1816		tcm->tcm_ifindex = qdisc_dev(q)->ifindex;
1817		tcm->tcm_parent = parent;
1818	} else {
1819		tcm->tcm_ifindex = TCM_IFINDEX_MAGIC_BLOCK;
1820		tcm->tcm_block_index = block->index;
1821	}
1822	tcm->tcm_info = TC_H_MAKE(tp->prio, tp->protocol);
1823	if (nla_put_string(skb, TCA_KIND, tp->ops->kind))
1824		goto nla_put_failure;
1825	if (nla_put_u32(skb, TCA_CHAIN, tp->chain->index))
1826		goto nla_put_failure;
1827	if (!fh) {
1828		tcm->tcm_handle = 0;
1829	} else if (terse_dump) {
1830		if (tp->ops->terse_dump) {
1831			if (tp->ops->terse_dump(net, tp, fh, skb, tcm,
1832						rtnl_held) < 0)
1833				goto nla_put_failure;
1834		} else {
1835			goto cls_op_not_supp;
1836		}
1837	} else {
1838		if (tp->ops->dump &&
1839		    tp->ops->dump(net, tp, fh, skb, tcm, rtnl_held) < 0)
1840			goto nla_put_failure;
1841	}
1842	nlh->nlmsg_len = skb_tail_pointer(skb) - b;
1843	return skb->len;
1844
1845out_nlmsg_trim:
1846nla_put_failure:
1847cls_op_not_supp:
1848	nlmsg_trim(skb, b);
1849	return -1;
1850}
1851
1852static int tfilter_notify(struct net *net, struct sk_buff *oskb,
1853			  struct nlmsghdr *n, struct tcf_proto *tp,
1854			  struct tcf_block *block, struct Qdisc *q,
1855			  u32 parent, void *fh, int event, bool unicast,
1856			  bool rtnl_held)
1857{
1858	struct sk_buff *skb;
1859	u32 portid = oskb ? NETLINK_CB(oskb).portid : 0;
1860	int err = 0;
1861
1862	skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
1863	if (!skb)
1864		return -ENOBUFS;
1865
1866	if (tcf_fill_node(net, skb, tp, block, q, parent, fh, portid,
1867			  n->nlmsg_seq, n->nlmsg_flags, event,
1868			  false, rtnl_held) <= 0) {
1869		kfree_skb(skb);
1870		return -EINVAL;
1871	}
1872
1873	if (unicast)
1874		err = netlink_unicast(net->rtnl, skb, portid, MSG_DONTWAIT);
1875	else
1876		err = rtnetlink_send(skb, net, portid, RTNLGRP_TC,
1877				     n->nlmsg_flags & NLM_F_ECHO);
1878
1879	if (err > 0)
1880		err = 0;
1881	return err;
1882}
1883
1884static int tfilter_del_notify(struct net *net, struct sk_buff *oskb,
1885			      struct nlmsghdr *n, struct tcf_proto *tp,
1886			      struct tcf_block *block, struct Qdisc *q,
1887			      u32 parent, void *fh, bool unicast, bool *last,
1888			      bool rtnl_held, struct netlink_ext_ack *extack)
1889{
1890	struct sk_buff *skb;
1891	u32 portid = oskb ? NETLINK_CB(oskb).portid : 0;
1892	int err;
1893
1894	skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
1895	if (!skb)
1896		return -ENOBUFS;
1897
1898	if (tcf_fill_node(net, skb, tp, block, q, parent, fh, portid,
1899			  n->nlmsg_seq, n->nlmsg_flags, RTM_DELTFILTER,
1900			  false, rtnl_held) <= 0) {
1901		NL_SET_ERR_MSG(extack, "Failed to build del event notification");
1902		kfree_skb(skb);
1903		return -EINVAL;
1904	}
1905
1906	err = tp->ops->delete(tp, fh, last, rtnl_held, extack);
1907	if (err) {
1908		kfree_skb(skb);
1909		return err;
1910	}
1911
1912	if (unicast)
1913		err = netlink_unicast(net->rtnl, skb, portid, MSG_DONTWAIT);
1914	else
1915		err = rtnetlink_send(skb, net, portid, RTNLGRP_TC,
1916				     n->nlmsg_flags & NLM_F_ECHO);
1917	if (err < 0)
1918		NL_SET_ERR_MSG(extack, "Failed to send filter delete notification");
1919
1920	if (err > 0)
1921		err = 0;
1922	return err;
1923}
1924
1925static void tfilter_notify_chain(struct net *net, struct sk_buff *oskb,
1926				 struct tcf_block *block, struct Qdisc *q,
1927				 u32 parent, struct nlmsghdr *n,
1928				 struct tcf_chain *chain, int event)
 
1929{
1930	struct tcf_proto *tp;
1931
1932	for (tp = tcf_get_next_proto(chain, NULL);
1933	     tp; tp = tcf_get_next_proto(chain, tp))
1934		tfilter_notify(net, oskb, n, tp, block,
1935			       q, parent, NULL, event, false, true);
1936}
1937
1938static void tfilter_put(struct tcf_proto *tp, void *fh)
1939{
1940	if (tp->ops->put && fh)
1941		tp->ops->put(tp, fh);
1942}
1943
1944static int tc_new_tfilter(struct sk_buff *skb, struct nlmsghdr *n,
1945			  struct netlink_ext_ack *extack)
1946{
1947	struct net *net = sock_net(skb->sk);
1948	struct nlattr *tca[TCA_MAX + 1];
1949	char name[IFNAMSIZ];
1950	struct tcmsg *t;
1951	u32 protocol;
1952	u32 prio;
1953	bool prio_allocate;
1954	u32 parent;
1955	u32 chain_index;
1956	struct Qdisc *q = NULL;
1957	struct tcf_chain_info chain_info;
1958	struct tcf_chain *chain = NULL;
1959	struct tcf_block *block;
1960	struct tcf_proto *tp;
1961	unsigned long cl;
1962	void *fh;
1963	int err;
1964	int tp_created;
1965	bool rtnl_held = false;
1966
1967	if (!netlink_ns_capable(skb, net->user_ns, CAP_NET_ADMIN))
1968		return -EPERM;
1969
1970replay:
1971	tp_created = 0;
1972
1973	err = nlmsg_parse_deprecated(n, sizeof(*t), tca, TCA_MAX,
1974				     rtm_tca_policy, extack);
1975	if (err < 0)
1976		return err;
1977
1978	t = nlmsg_data(n);
1979	protocol = TC_H_MIN(t->tcm_info);
1980	prio = TC_H_MAJ(t->tcm_info);
1981	prio_allocate = false;
1982	parent = t->tcm_parent;
1983	tp = NULL;
1984	cl = 0;
1985	block = NULL;
1986
1987	if (prio == 0) {
1988		/* If no priority is provided by the user,
1989		 * we allocate one.
1990		 */
1991		if (n->nlmsg_flags & NLM_F_CREATE) {
1992			prio = TC_H_MAKE(0x80000000U, 0U);
1993			prio_allocate = true;
1994		} else {
1995			NL_SET_ERR_MSG(extack, "Invalid filter command with priority of zero");
1996			return -ENOENT;
1997		}
1998	}
1999
2000	/* Find head of filter chain. */
2001
2002	err = __tcf_qdisc_find(net, &q, &parent, t->tcm_ifindex, false, extack);
2003	if (err)
2004		return err;
2005
2006	if (tcf_proto_check_kind(tca[TCA_KIND], name)) {
2007		NL_SET_ERR_MSG(extack, "Specified TC filter name too long");
2008		err = -EINVAL;
2009		goto errout;
2010	}
2011
2012	/* Take rtnl mutex if rtnl_held was set to true on previous iteration,
2013	 * block is shared (no qdisc found), qdisc is not unlocked, classifier
2014	 * type is not specified, classifier is not unlocked.
2015	 */
2016	if (rtnl_held ||
2017	    (q && !(q->ops->cl_ops->flags & QDISC_CLASS_OPS_DOIT_UNLOCKED)) ||
2018	    !tcf_proto_is_unlocked(name)) {
2019		rtnl_held = true;
2020		rtnl_lock();
2021	}
2022
2023	err = __tcf_qdisc_cl_find(q, parent, &cl, t->tcm_ifindex, extack);
2024	if (err)
2025		goto errout;
2026
2027	block = __tcf_block_find(net, q, cl, t->tcm_ifindex, t->tcm_block_index,
2028				 extack);
2029	if (IS_ERR(block)) {
2030		err = PTR_ERR(block);
2031		goto errout;
2032	}
2033	block->classid = parent;
2034
2035	chain_index = tca[TCA_CHAIN] ? nla_get_u32(tca[TCA_CHAIN]) : 0;
2036	if (chain_index > TC_ACT_EXT_VAL_MASK) {
2037		NL_SET_ERR_MSG(extack, "Specified chain index exceeds upper limit");
2038		err = -EINVAL;
2039		goto errout;
2040	}
2041	chain = tcf_chain_get(block, chain_index, true);
2042	if (!chain) {
2043		NL_SET_ERR_MSG(extack, "Cannot create specified filter chain");
2044		err = -ENOMEM;
2045		goto errout;
2046	}
2047
2048	mutex_lock(&chain->filter_chain_lock);
2049	tp = tcf_chain_tp_find(chain, &chain_info, protocol,
2050			       prio, prio_allocate);
2051	if (IS_ERR(tp)) {
2052		NL_SET_ERR_MSG(extack, "Filter with specified priority/protocol not found");
2053		err = PTR_ERR(tp);
2054		goto errout_locked;
2055	}
2056
2057	if (tp == NULL) {
2058		struct tcf_proto *tp_new = NULL;
2059
2060		if (chain->flushing) {
2061			err = -EAGAIN;
2062			goto errout_locked;
2063		}
2064
2065		/* Proto-tcf does not exist, create new one */
2066
2067		if (tca[TCA_KIND] == NULL || !protocol) {
2068			NL_SET_ERR_MSG(extack, "Filter kind and protocol must be specified");
2069			err = -EINVAL;
2070			goto errout_locked;
2071		}
2072
2073		if (!(n->nlmsg_flags & NLM_F_CREATE)) {
2074			NL_SET_ERR_MSG(extack, "Need both RTM_NEWTFILTER and NLM_F_CREATE to create a new filter");
2075			err = -ENOENT;
2076			goto errout_locked;
2077		}
2078
2079		if (prio_allocate)
2080			prio = tcf_auto_prio(tcf_chain_tp_prev(chain,
2081							       &chain_info));
2082
2083		mutex_unlock(&chain->filter_chain_lock);
2084		tp_new = tcf_proto_create(name, protocol, prio, chain,
2085					  rtnl_held, extack);
 
2086		if (IS_ERR(tp_new)) {
2087			err = PTR_ERR(tp_new);
2088			goto errout_tp;
2089		}
2090
2091		tp_created = 1;
2092		tp = tcf_chain_tp_insert_unique(chain, tp_new, protocol, prio,
2093						rtnl_held);
2094		if (IS_ERR(tp)) {
2095			err = PTR_ERR(tp);
2096			goto errout_tp;
2097		}
2098	} else {
2099		mutex_unlock(&chain->filter_chain_lock);
2100	}
2101
2102	if (tca[TCA_KIND] && nla_strcmp(tca[TCA_KIND], tp->ops->kind)) {
2103		NL_SET_ERR_MSG(extack, "Specified filter kind does not match existing one");
2104		err = -EINVAL;
2105		goto errout;
2106	}
2107
2108	fh = tp->ops->get(tp, t->tcm_handle);
2109
2110	if (!fh) {
2111		if (!(n->nlmsg_flags & NLM_F_CREATE)) {
2112			NL_SET_ERR_MSG(extack, "Need both RTM_NEWTFILTER and NLM_F_CREATE to create a new filter");
2113			err = -ENOENT;
2114			goto errout;
2115		}
2116	} else if (n->nlmsg_flags & NLM_F_EXCL) {
2117		tfilter_put(tp, fh);
2118		NL_SET_ERR_MSG(extack, "Filter already exists");
2119		err = -EEXIST;
2120		goto errout;
2121	}
2122
2123	if (chain->tmplt_ops && chain->tmplt_ops != tp->ops) {
2124		NL_SET_ERR_MSG(extack, "Chain template is set to a different filter kind");
2125		err = -EINVAL;
2126		goto errout;
2127	}
2128
2129	err = tp->ops->change(net, skb, tp, cl, t->tcm_handle, tca, &fh,
2130			      n->nlmsg_flags & NLM_F_CREATE ? TCA_ACT_NOREPLACE : TCA_ACT_REPLACE,
2131			      rtnl_held, extack);
2132	if (err == 0) {
2133		tfilter_notify(net, skb, n, tp, block, q, parent, fh,
2134			       RTM_NEWTFILTER, false, rtnl_held);
2135		tfilter_put(tp, fh);
2136		/* q pointer is NULL for shared blocks */
2137		if (q)
2138			q->flags &= ~TCQ_F_CAN_BYPASS;
2139	}
2140
2141errout:
2142	if (err && tp_created)
2143		tcf_chain_tp_delete_empty(chain, tp, rtnl_held, NULL);
2144errout_tp:
2145	if (chain) {
2146		if (tp && !IS_ERR(tp))
2147			tcf_proto_put(tp, rtnl_held, NULL);
2148		if (!tp_created)
2149			tcf_chain_put(chain);
2150	}
2151	tcf_block_release(q, block, rtnl_held);
2152
2153	if (rtnl_held)
2154		rtnl_unlock();
2155
2156	if (err == -EAGAIN) {
2157		/* Take rtnl lock in case EAGAIN is caused by concurrent flush
2158		 * of target chain.
2159		 */
2160		rtnl_held = true;
2161		/* Replay the request. */
2162		goto replay;
2163	}
2164	return err;
2165
2166errout_locked:
2167	mutex_unlock(&chain->filter_chain_lock);
2168	goto errout;
2169}
2170
2171static int tc_del_tfilter(struct sk_buff *skb, struct nlmsghdr *n,
2172			  struct netlink_ext_ack *extack)
2173{
2174	struct net *net = sock_net(skb->sk);
2175	struct nlattr *tca[TCA_MAX + 1];
2176	char name[IFNAMSIZ];
2177	struct tcmsg *t;
2178	u32 protocol;
2179	u32 prio;
2180	u32 parent;
2181	u32 chain_index;
2182	struct Qdisc *q = NULL;
2183	struct tcf_chain_info chain_info;
2184	struct tcf_chain *chain = NULL;
2185	struct tcf_block *block = NULL;
2186	struct tcf_proto *tp = NULL;
2187	unsigned long cl = 0;
2188	void *fh = NULL;
2189	int err;
2190	bool rtnl_held = false;
2191
2192	if (!netlink_ns_capable(skb, net->user_ns, CAP_NET_ADMIN))
2193		return -EPERM;
2194
2195	err = nlmsg_parse_deprecated(n, sizeof(*t), tca, TCA_MAX,
2196				     rtm_tca_policy, extack);
2197	if (err < 0)
2198		return err;
2199
2200	t = nlmsg_data(n);
2201	protocol = TC_H_MIN(t->tcm_info);
2202	prio = TC_H_MAJ(t->tcm_info);
2203	parent = t->tcm_parent;
2204
2205	if (prio == 0 && (protocol || t->tcm_handle || tca[TCA_KIND])) {
2206		NL_SET_ERR_MSG(extack, "Cannot flush filters with protocol, handle or kind set");
2207		return -ENOENT;
2208	}
2209
2210	/* Find head of filter chain. */
2211
2212	err = __tcf_qdisc_find(net, &q, &parent, t->tcm_ifindex, false, extack);
2213	if (err)
2214		return err;
2215
2216	if (tcf_proto_check_kind(tca[TCA_KIND], name)) {
2217		NL_SET_ERR_MSG(extack, "Specified TC filter name too long");
2218		err = -EINVAL;
2219		goto errout;
2220	}
2221	/* Take rtnl mutex if flushing whole chain, block is shared (no qdisc
2222	 * found), qdisc is not unlocked, classifier type is not specified,
2223	 * classifier is not unlocked.
2224	 */
2225	if (!prio ||
2226	    (q && !(q->ops->cl_ops->flags & QDISC_CLASS_OPS_DOIT_UNLOCKED)) ||
2227	    !tcf_proto_is_unlocked(name)) {
2228		rtnl_held = true;
2229		rtnl_lock();
2230	}
2231
2232	err = __tcf_qdisc_cl_find(q, parent, &cl, t->tcm_ifindex, extack);
2233	if (err)
2234		goto errout;
2235
2236	block = __tcf_block_find(net, q, cl, t->tcm_ifindex, t->tcm_block_index,
2237				 extack);
2238	if (IS_ERR(block)) {
2239		err = PTR_ERR(block);
2240		goto errout;
2241	}
2242
2243	chain_index = tca[TCA_CHAIN] ? nla_get_u32(tca[TCA_CHAIN]) : 0;
2244	if (chain_index > TC_ACT_EXT_VAL_MASK) {
2245		NL_SET_ERR_MSG(extack, "Specified chain index exceeds upper limit");
2246		err = -EINVAL;
2247		goto errout;
2248	}
2249	chain = tcf_chain_get(block, chain_index, false);
2250	if (!chain) {
2251		/* User requested flush on non-existent chain. Nothing to do,
2252		 * so just return success.
2253		 */
2254		if (prio == 0) {
2255			err = 0;
2256			goto errout;
2257		}
2258		NL_SET_ERR_MSG(extack, "Cannot find specified filter chain");
2259		err = -ENOENT;
2260		goto errout;
2261	}
2262
2263	if (prio == 0) {
2264		tfilter_notify_chain(net, skb, block, q, parent, n,
2265				     chain, RTM_DELTFILTER);
2266		tcf_chain_flush(chain, rtnl_held);
2267		err = 0;
2268		goto errout;
2269	}
2270
2271	mutex_lock(&chain->filter_chain_lock);
2272	tp = tcf_chain_tp_find(chain, &chain_info, protocol,
2273			       prio, false);
2274	if (!tp || IS_ERR(tp)) {
2275		NL_SET_ERR_MSG(extack, "Filter with specified priority/protocol not found");
2276		err = tp ? PTR_ERR(tp) : -ENOENT;
2277		goto errout_locked;
2278	} else if (tca[TCA_KIND] && nla_strcmp(tca[TCA_KIND], tp->ops->kind)) {
2279		NL_SET_ERR_MSG(extack, "Specified filter kind does not match existing one");
2280		err = -EINVAL;
2281		goto errout_locked;
2282	} else if (t->tcm_handle == 0) {
2283		tcf_proto_signal_destroying(chain, tp);
2284		tcf_chain_tp_remove(chain, &chain_info, tp);
2285		mutex_unlock(&chain->filter_chain_lock);
2286
2287		tcf_proto_put(tp, rtnl_held, NULL);
2288		tfilter_notify(net, skb, n, tp, block, q, parent, fh,
2289			       RTM_DELTFILTER, false, rtnl_held);
2290		err = 0;
2291		goto errout;
2292	}
2293	mutex_unlock(&chain->filter_chain_lock);
2294
2295	fh = tp->ops->get(tp, t->tcm_handle);
2296
2297	if (!fh) {
2298		NL_SET_ERR_MSG(extack, "Specified filter handle not found");
2299		err = -ENOENT;
2300	} else {
2301		bool last;
2302
2303		err = tfilter_del_notify(net, skb, n, tp, block,
2304					 q, parent, fh, false, &last,
2305					 rtnl_held, extack);
2306
2307		if (err)
2308			goto errout;
2309		if (last)
2310			tcf_chain_tp_delete_empty(chain, tp, rtnl_held, extack);
2311	}
2312
2313errout:
2314	if (chain) {
2315		if (tp && !IS_ERR(tp))
2316			tcf_proto_put(tp, rtnl_held, NULL);
2317		tcf_chain_put(chain);
2318	}
2319	tcf_block_release(q, block, rtnl_held);
2320
2321	if (rtnl_held)
2322		rtnl_unlock();
2323
2324	return err;
2325
2326errout_locked:
2327	mutex_unlock(&chain->filter_chain_lock);
2328	goto errout;
2329}
2330
2331static int tc_get_tfilter(struct sk_buff *skb, struct nlmsghdr *n,
2332			  struct netlink_ext_ack *extack)
2333{
2334	struct net *net = sock_net(skb->sk);
2335	struct nlattr *tca[TCA_MAX + 1];
2336	char name[IFNAMSIZ];
2337	struct tcmsg *t;
2338	u32 protocol;
2339	u32 prio;
2340	u32 parent;
2341	u32 chain_index;
2342	struct Qdisc *q = NULL;
2343	struct tcf_chain_info chain_info;
2344	struct tcf_chain *chain = NULL;
2345	struct tcf_block *block = NULL;
2346	struct tcf_proto *tp = NULL;
2347	unsigned long cl = 0;
2348	void *fh = NULL;
2349	int err;
2350	bool rtnl_held = false;
2351
2352	err = nlmsg_parse_deprecated(n, sizeof(*t), tca, TCA_MAX,
2353				     rtm_tca_policy, extack);
2354	if (err < 0)
2355		return err;
2356
2357	t = nlmsg_data(n);
2358	protocol = TC_H_MIN(t->tcm_info);
2359	prio = TC_H_MAJ(t->tcm_info);
2360	parent = t->tcm_parent;
2361
2362	if (prio == 0) {
2363		NL_SET_ERR_MSG(extack, "Invalid filter command with priority of zero");
2364		return -ENOENT;
2365	}
2366
2367	/* Find head of filter chain. */
2368
2369	err = __tcf_qdisc_find(net, &q, &parent, t->tcm_ifindex, false, extack);
2370	if (err)
2371		return err;
2372
2373	if (tcf_proto_check_kind(tca[TCA_KIND], name)) {
2374		NL_SET_ERR_MSG(extack, "Specified TC filter name too long");
2375		err = -EINVAL;
2376		goto errout;
2377	}
2378	/* Take rtnl mutex if block is shared (no qdisc found), qdisc is not
2379	 * unlocked, classifier type is not specified, classifier is not
2380	 * unlocked.
2381	 */
2382	if ((q && !(q->ops->cl_ops->flags & QDISC_CLASS_OPS_DOIT_UNLOCKED)) ||
2383	    !tcf_proto_is_unlocked(name)) {
2384		rtnl_held = true;
2385		rtnl_lock();
2386	}
2387
2388	err = __tcf_qdisc_cl_find(q, parent, &cl, t->tcm_ifindex, extack);
2389	if (err)
2390		goto errout;
2391
2392	block = __tcf_block_find(net, q, cl, t->tcm_ifindex, t->tcm_block_index,
2393				 extack);
2394	if (IS_ERR(block)) {
2395		err = PTR_ERR(block);
2396		goto errout;
2397	}
2398
2399	chain_index = tca[TCA_CHAIN] ? nla_get_u32(tca[TCA_CHAIN]) : 0;
2400	if (chain_index > TC_ACT_EXT_VAL_MASK) {
2401		NL_SET_ERR_MSG(extack, "Specified chain index exceeds upper limit");
2402		err = -EINVAL;
2403		goto errout;
2404	}
2405	chain = tcf_chain_get(block, chain_index, false);
2406	if (!chain) {
2407		NL_SET_ERR_MSG(extack, "Cannot find specified filter chain");
2408		err = -EINVAL;
2409		goto errout;
2410	}
2411
2412	mutex_lock(&chain->filter_chain_lock);
2413	tp = tcf_chain_tp_find(chain, &chain_info, protocol,
2414			       prio, false);
2415	mutex_unlock(&chain->filter_chain_lock);
2416	if (!tp || IS_ERR(tp)) {
2417		NL_SET_ERR_MSG(extack, "Filter with specified priority/protocol not found");
2418		err = tp ? PTR_ERR(tp) : -ENOENT;
2419		goto errout;
2420	} else if (tca[TCA_KIND] && nla_strcmp(tca[TCA_KIND], tp->ops->kind)) {
2421		NL_SET_ERR_MSG(extack, "Specified filter kind does not match existing one");
2422		err = -EINVAL;
2423		goto errout;
2424	}
2425
2426	fh = tp->ops->get(tp, t->tcm_handle);
2427
2428	if (!fh) {
2429		NL_SET_ERR_MSG(extack, "Specified filter handle not found");
2430		err = -ENOENT;
2431	} else {
2432		err = tfilter_notify(net, skb, n, tp, block, q, parent,
2433				     fh, RTM_NEWTFILTER, true, rtnl_held);
2434		if (err < 0)
2435			NL_SET_ERR_MSG(extack, "Failed to send filter notify message");
2436	}
2437
2438	tfilter_put(tp, fh);
2439errout:
2440	if (chain) {
2441		if (tp && !IS_ERR(tp))
2442			tcf_proto_put(tp, rtnl_held, NULL);
2443		tcf_chain_put(chain);
2444	}
2445	tcf_block_release(q, block, rtnl_held);
2446
2447	if (rtnl_held)
2448		rtnl_unlock();
2449
2450	return err;
2451}
2452
2453struct tcf_dump_args {
2454	struct tcf_walker w;
2455	struct sk_buff *skb;
2456	struct netlink_callback *cb;
2457	struct tcf_block *block;
2458	struct Qdisc *q;
2459	u32 parent;
2460	bool terse_dump;
2461};
2462
2463static int tcf_node_dump(struct tcf_proto *tp, void *n, struct tcf_walker *arg)
2464{
2465	struct tcf_dump_args *a = (void *)arg;
2466	struct net *net = sock_net(a->skb->sk);
2467
2468	return tcf_fill_node(net, a->skb, tp, a->block, a->q, a->parent,
2469			     n, NETLINK_CB(a->cb->skb).portid,
2470			     a->cb->nlh->nlmsg_seq, NLM_F_MULTI,
2471			     RTM_NEWTFILTER, a->terse_dump, true);
2472}
2473
2474static bool tcf_chain_dump(struct tcf_chain *chain, struct Qdisc *q, u32 parent,
2475			   struct sk_buff *skb, struct netlink_callback *cb,
2476			   long index_start, long *p_index, bool terse)
2477{
2478	struct net *net = sock_net(skb->sk);
2479	struct tcf_block *block = chain->block;
2480	struct tcmsg *tcm = nlmsg_data(cb->nlh);
2481	struct tcf_proto *tp, *tp_prev;
2482	struct tcf_dump_args arg;
2483
2484	for (tp = __tcf_get_next_proto(chain, NULL);
2485	     tp;
2486	     tp_prev = tp,
2487		     tp = __tcf_get_next_proto(chain, tp),
2488		     tcf_proto_put(tp_prev, true, NULL),
2489		     (*p_index)++) {
2490		if (*p_index < index_start)
2491			continue;
2492		if (TC_H_MAJ(tcm->tcm_info) &&
2493		    TC_H_MAJ(tcm->tcm_info) != tp->prio)
2494			continue;
2495		if (TC_H_MIN(tcm->tcm_info) &&
2496		    TC_H_MIN(tcm->tcm_info) != tp->protocol)
2497			continue;
2498		if (*p_index > index_start)
2499			memset(&cb->args[1], 0,
2500			       sizeof(cb->args) - sizeof(cb->args[0]));
2501		if (cb->args[1] == 0) {
2502			if (tcf_fill_node(net, skb, tp, block, q, parent, NULL,
2503					  NETLINK_CB(cb->skb).portid,
2504					  cb->nlh->nlmsg_seq, NLM_F_MULTI,
2505					  RTM_NEWTFILTER, false, true) <= 0)
2506				goto errout;
2507			cb->args[1] = 1;
2508		}
2509		if (!tp->ops->walk)
2510			continue;
2511		arg.w.fn = tcf_node_dump;
2512		arg.skb = skb;
2513		arg.cb = cb;
2514		arg.block = block;
2515		arg.q = q;
2516		arg.parent = parent;
2517		arg.w.stop = 0;
2518		arg.w.skip = cb->args[1] - 1;
2519		arg.w.count = 0;
2520		arg.w.cookie = cb->args[2];
2521		arg.terse_dump = terse;
2522		tp->ops->walk(tp, &arg.w, true);
2523		cb->args[2] = arg.w.cookie;
2524		cb->args[1] = arg.w.count + 1;
2525		if (arg.w.stop)
2526			goto errout;
2527	}
2528	return true;
2529
2530errout:
2531	tcf_proto_put(tp, true, NULL);
2532	return false;
2533}
2534
2535static const struct nla_policy tcf_tfilter_dump_policy[TCA_MAX + 1] = {
2536	[TCA_DUMP_FLAGS] = NLA_POLICY_BITFIELD32(TCA_DUMP_FLAGS_TERSE),
2537};
2538
2539/* called with RTNL */
2540static int tc_dump_tfilter(struct sk_buff *skb, struct netlink_callback *cb)
2541{
2542	struct tcf_chain *chain, *chain_prev;
2543	struct net *net = sock_net(skb->sk);
2544	struct nlattr *tca[TCA_MAX + 1];
2545	struct Qdisc *q = NULL;
2546	struct tcf_block *block;
2547	struct tcmsg *tcm = nlmsg_data(cb->nlh);
2548	bool terse_dump = false;
2549	long index_start;
2550	long index;
2551	u32 parent;
2552	int err;
2553
2554	if (nlmsg_len(cb->nlh) < sizeof(*tcm))
2555		return skb->len;
2556
2557	err = nlmsg_parse_deprecated(cb->nlh, sizeof(*tcm), tca, TCA_MAX,
2558				     tcf_tfilter_dump_policy, cb->extack);
2559	if (err)
2560		return err;
2561
2562	if (tca[TCA_DUMP_FLAGS]) {
2563		struct nla_bitfield32 flags =
2564			nla_get_bitfield32(tca[TCA_DUMP_FLAGS]);
2565
2566		terse_dump = flags.value & TCA_DUMP_FLAGS_TERSE;
2567	}
2568
2569	if (tcm->tcm_ifindex == TCM_IFINDEX_MAGIC_BLOCK) {
2570		block = tcf_block_refcnt_get(net, tcm->tcm_block_index);
2571		if (!block)
2572			goto out;
2573		/* If we work with block index, q is NULL and parent value
2574		 * will never be used in the following code. The check
2575		 * in tcf_fill_node prevents it. However, compiler does not
2576		 * see that far, so set parent to zero to silence the warning
2577		 * about parent being uninitialized.
2578		 */
2579		parent = 0;
2580	} else {
2581		const struct Qdisc_class_ops *cops;
2582		struct net_device *dev;
2583		unsigned long cl = 0;
2584
2585		dev = __dev_get_by_index(net, tcm->tcm_ifindex);
2586		if (!dev)
2587			return skb->len;
2588
2589		parent = tcm->tcm_parent;
2590		if (!parent)
2591			q = dev->qdisc;
2592		else
 
2593			q = qdisc_lookup(dev, TC_H_MAJ(tcm->tcm_parent));
 
2594		if (!q)
2595			goto out;
2596		cops = q->ops->cl_ops;
2597		if (!cops)
2598			goto out;
2599		if (!cops->tcf_block)
2600			goto out;
2601		if (TC_H_MIN(tcm->tcm_parent)) {
2602			cl = cops->find(q, tcm->tcm_parent);
2603			if (cl == 0)
2604				goto out;
2605		}
2606		block = cops->tcf_block(q, cl, NULL);
2607		if (!block)
2608			goto out;
2609		parent = block->classid;
2610		if (tcf_block_shared(block))
2611			q = NULL;
2612	}
2613
2614	index_start = cb->args[0];
2615	index = 0;
2616
2617	for (chain = __tcf_get_next_chain(block, NULL);
2618	     chain;
2619	     chain_prev = chain,
2620		     chain = __tcf_get_next_chain(block, chain),
2621		     tcf_chain_put(chain_prev)) {
2622		if (tca[TCA_CHAIN] &&
2623		    nla_get_u32(tca[TCA_CHAIN]) != chain->index)
2624			continue;
2625		if (!tcf_chain_dump(chain, q, parent, skb, cb,
2626				    index_start, &index, terse_dump)) {
2627			tcf_chain_put(chain);
2628			err = -EMSGSIZE;
2629			break;
2630		}
2631	}
2632
2633	if (tcm->tcm_ifindex == TCM_IFINDEX_MAGIC_BLOCK)
2634		tcf_block_refcnt_put(block, true);
2635	cb->args[0] = index;
2636
2637out:
2638	/* If we did no progress, the error (EMSGSIZE) is real */
2639	if (skb->len == 0 && err)
2640		return err;
2641	return skb->len;
2642}
2643
2644static int tc_chain_fill_node(const struct tcf_proto_ops *tmplt_ops,
2645			      void *tmplt_priv, u32 chain_index,
2646			      struct net *net, struct sk_buff *skb,
2647			      struct tcf_block *block,
2648			      u32 portid, u32 seq, u16 flags, int event)
2649{
2650	unsigned char *b = skb_tail_pointer(skb);
2651	const struct tcf_proto_ops *ops;
2652	struct nlmsghdr *nlh;
2653	struct tcmsg *tcm;
2654	void *priv;
2655
2656	ops = tmplt_ops;
2657	priv = tmplt_priv;
2658
2659	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*tcm), flags);
2660	if (!nlh)
2661		goto out_nlmsg_trim;
2662	tcm = nlmsg_data(nlh);
2663	tcm->tcm_family = AF_UNSPEC;
2664	tcm->tcm__pad1 = 0;
2665	tcm->tcm__pad2 = 0;
2666	tcm->tcm_handle = 0;
2667	if (block->q) {
2668		tcm->tcm_ifindex = qdisc_dev(block->q)->ifindex;
2669		tcm->tcm_parent = block->q->handle;
2670	} else {
2671		tcm->tcm_ifindex = TCM_IFINDEX_MAGIC_BLOCK;
2672		tcm->tcm_block_index = block->index;
2673	}
2674
2675	if (nla_put_u32(skb, TCA_CHAIN, chain_index))
2676		goto nla_put_failure;
2677
2678	if (ops) {
2679		if (nla_put_string(skb, TCA_KIND, ops->kind))
2680			goto nla_put_failure;
2681		if (ops->tmplt_dump(skb, net, priv) < 0)
2682			goto nla_put_failure;
2683	}
2684
2685	nlh->nlmsg_len = skb_tail_pointer(skb) - b;
2686	return skb->len;
2687
2688out_nlmsg_trim:
2689nla_put_failure:
2690	nlmsg_trim(skb, b);
2691	return -EMSGSIZE;
2692}
2693
2694static int tc_chain_notify(struct tcf_chain *chain, struct sk_buff *oskb,
2695			   u32 seq, u16 flags, int event, bool unicast)
2696{
2697	u32 portid = oskb ? NETLINK_CB(oskb).portid : 0;
2698	struct tcf_block *block = chain->block;
2699	struct net *net = block->net;
2700	struct sk_buff *skb;
2701	int err = 0;
2702
2703	skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
2704	if (!skb)
2705		return -ENOBUFS;
2706
2707	if (tc_chain_fill_node(chain->tmplt_ops, chain->tmplt_priv,
2708			       chain->index, net, skb, block, portid,
2709			       seq, flags, event) <= 0) {
2710		kfree_skb(skb);
2711		return -EINVAL;
2712	}
2713
2714	if (unicast)
2715		err = netlink_unicast(net->rtnl, skb, portid, MSG_DONTWAIT);
2716	else
2717		err = rtnetlink_send(skb, net, portid, RTNLGRP_TC,
2718				     flags & NLM_F_ECHO);
2719
2720	if (err > 0)
2721		err = 0;
2722	return err;
2723}
2724
2725static int tc_chain_notify_delete(const struct tcf_proto_ops *tmplt_ops,
2726				  void *tmplt_priv, u32 chain_index,
2727				  struct tcf_block *block, struct sk_buff *oskb,
2728				  u32 seq, u16 flags, bool unicast)
2729{
2730	u32 portid = oskb ? NETLINK_CB(oskb).portid : 0;
2731	struct net *net = block->net;
2732	struct sk_buff *skb;
2733
2734	skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
2735	if (!skb)
2736		return -ENOBUFS;
2737
2738	if (tc_chain_fill_node(tmplt_ops, tmplt_priv, chain_index, net, skb,
2739			       block, portid, seq, flags, RTM_DELCHAIN) <= 0) {
2740		kfree_skb(skb);
2741		return -EINVAL;
2742	}
2743
2744	if (unicast)
2745		return netlink_unicast(net->rtnl, skb, portid, MSG_DONTWAIT);
2746
2747	return rtnetlink_send(skb, net, portid, RTNLGRP_TC, flags & NLM_F_ECHO);
2748}
2749
2750static int tc_chain_tmplt_add(struct tcf_chain *chain, struct net *net,
2751			      struct nlattr **tca,
2752			      struct netlink_ext_ack *extack)
2753{
2754	const struct tcf_proto_ops *ops;
2755	char name[IFNAMSIZ];
2756	void *tmplt_priv;
2757
2758	/* If kind is not set, user did not specify template. */
2759	if (!tca[TCA_KIND])
2760		return 0;
2761
2762	if (tcf_proto_check_kind(tca[TCA_KIND], name)) {
2763		NL_SET_ERR_MSG(extack, "Specified TC chain template name too long");
2764		return -EINVAL;
2765	}
2766
2767	ops = tcf_proto_lookup_ops(name, true, extack);
2768	if (IS_ERR(ops))
2769		return PTR_ERR(ops);
2770	if (!ops->tmplt_create || !ops->tmplt_destroy || !ops->tmplt_dump) {
2771		NL_SET_ERR_MSG(extack, "Chain templates are not supported with specified classifier");
2772		return -EOPNOTSUPP;
2773	}
2774
2775	tmplt_priv = ops->tmplt_create(net, chain, tca, extack);
2776	if (IS_ERR(tmplt_priv)) {
2777		module_put(ops->owner);
2778		return PTR_ERR(tmplt_priv);
2779	}
2780	chain->tmplt_ops = ops;
2781	chain->tmplt_priv = tmplt_priv;
2782	return 0;
2783}
2784
2785static void tc_chain_tmplt_del(const struct tcf_proto_ops *tmplt_ops,
2786			       void *tmplt_priv)
2787{
2788	/* If template ops are set, no work to do for us. */
2789	if (!tmplt_ops)
2790		return;
2791
2792	tmplt_ops->tmplt_destroy(tmplt_priv);
2793	module_put(tmplt_ops->owner);
2794}
2795
2796/* Add/delete/get a chain */
2797
2798static int tc_ctl_chain(struct sk_buff *skb, struct nlmsghdr *n,
2799			struct netlink_ext_ack *extack)
2800{
2801	struct net *net = sock_net(skb->sk);
2802	struct nlattr *tca[TCA_MAX + 1];
2803	struct tcmsg *t;
2804	u32 parent;
2805	u32 chain_index;
2806	struct Qdisc *q = NULL;
2807	struct tcf_chain *chain = NULL;
2808	struct tcf_block *block;
2809	unsigned long cl;
2810	int err;
2811
2812	if (n->nlmsg_type != RTM_GETCHAIN &&
2813	    !netlink_ns_capable(skb, net->user_ns, CAP_NET_ADMIN))
2814		return -EPERM;
2815
2816replay:
2817	err = nlmsg_parse_deprecated(n, sizeof(*t), tca, TCA_MAX,
2818				     rtm_tca_policy, extack);
2819	if (err < 0)
2820		return err;
2821
2822	t = nlmsg_data(n);
2823	parent = t->tcm_parent;
2824	cl = 0;
2825
2826	block = tcf_block_find(net, &q, &parent, &cl,
2827			       t->tcm_ifindex, t->tcm_block_index, extack);
2828	if (IS_ERR(block))
2829		return PTR_ERR(block);
2830
2831	chain_index = tca[TCA_CHAIN] ? nla_get_u32(tca[TCA_CHAIN]) : 0;
2832	if (chain_index > TC_ACT_EXT_VAL_MASK) {
2833		NL_SET_ERR_MSG(extack, "Specified chain index exceeds upper limit");
2834		err = -EINVAL;
2835		goto errout_block;
2836	}
2837
2838	mutex_lock(&block->lock);
2839	chain = tcf_chain_lookup(block, chain_index);
2840	if (n->nlmsg_type == RTM_NEWCHAIN) {
2841		if (chain) {
2842			if (tcf_chain_held_by_acts_only(chain)) {
2843				/* The chain exists only because there is
2844				 * some action referencing it.
2845				 */
2846				tcf_chain_hold(chain);
2847			} else {
2848				NL_SET_ERR_MSG(extack, "Filter chain already exists");
2849				err = -EEXIST;
2850				goto errout_block_locked;
2851			}
2852		} else {
2853			if (!(n->nlmsg_flags & NLM_F_CREATE)) {
2854				NL_SET_ERR_MSG(extack, "Need both RTM_NEWCHAIN and NLM_F_CREATE to create a new chain");
2855				err = -ENOENT;
2856				goto errout_block_locked;
2857			}
2858			chain = tcf_chain_create(block, chain_index);
2859			if (!chain) {
2860				NL_SET_ERR_MSG(extack, "Failed to create filter chain");
2861				err = -ENOMEM;
2862				goto errout_block_locked;
2863			}
2864		}
2865	} else {
2866		if (!chain || tcf_chain_held_by_acts_only(chain)) {
2867			NL_SET_ERR_MSG(extack, "Cannot find specified filter chain");
2868			err = -EINVAL;
2869			goto errout_block_locked;
2870		}
2871		tcf_chain_hold(chain);
2872	}
2873
2874	if (n->nlmsg_type == RTM_NEWCHAIN) {
2875		/* Modifying chain requires holding parent block lock. In case
2876		 * the chain was successfully added, take a reference to the
2877		 * chain. This ensures that an empty chain does not disappear at
2878		 * the end of this function.
2879		 */
2880		tcf_chain_hold(chain);
2881		chain->explicitly_created = true;
2882	}
2883	mutex_unlock(&block->lock);
2884
2885	switch (n->nlmsg_type) {
2886	case RTM_NEWCHAIN:
2887		err = tc_chain_tmplt_add(chain, net, tca, extack);
2888		if (err) {
2889			tcf_chain_put_explicitly_created(chain);
2890			goto errout;
2891		}
2892
2893		tc_chain_notify(chain, NULL, 0, NLM_F_CREATE | NLM_F_EXCL,
2894				RTM_NEWCHAIN, false);
2895		break;
2896	case RTM_DELCHAIN:
2897		tfilter_notify_chain(net, skb, block, q, parent, n,
2898				     chain, RTM_DELTFILTER);
2899		/* Flush the chain first as the user requested chain removal. */
2900		tcf_chain_flush(chain, true);
2901		/* In case the chain was successfully deleted, put a reference
2902		 * to the chain previously taken during addition.
2903		 */
2904		tcf_chain_put_explicitly_created(chain);
2905		break;
2906	case RTM_GETCHAIN:
2907		err = tc_chain_notify(chain, skb, n->nlmsg_seq,
2908				      n->nlmsg_flags, n->nlmsg_type, true);
2909		if (err < 0)
2910			NL_SET_ERR_MSG(extack, "Failed to send chain notify message");
2911		break;
2912	default:
2913		err = -EOPNOTSUPP;
2914		NL_SET_ERR_MSG(extack, "Unsupported message type");
2915		goto errout;
2916	}
2917
2918errout:
2919	tcf_chain_put(chain);
2920errout_block:
2921	tcf_block_release(q, block, true);
2922	if (err == -EAGAIN)
2923		/* Replay the request. */
2924		goto replay;
2925	return err;
2926
2927errout_block_locked:
2928	mutex_unlock(&block->lock);
2929	goto errout_block;
2930}
2931
2932/* called with RTNL */
2933static int tc_dump_chain(struct sk_buff *skb, struct netlink_callback *cb)
2934{
2935	struct net *net = sock_net(skb->sk);
2936	struct nlattr *tca[TCA_MAX + 1];
2937	struct Qdisc *q = NULL;
2938	struct tcf_block *block;
2939	struct tcmsg *tcm = nlmsg_data(cb->nlh);
2940	struct tcf_chain *chain;
2941	long index_start;
2942	long index;
 
2943	int err;
2944
2945	if (nlmsg_len(cb->nlh) < sizeof(*tcm))
2946		return skb->len;
2947
2948	err = nlmsg_parse_deprecated(cb->nlh, sizeof(*tcm), tca, TCA_MAX,
2949				     rtm_tca_policy, cb->extack);
2950	if (err)
2951		return err;
2952
2953	if (tcm->tcm_ifindex == TCM_IFINDEX_MAGIC_BLOCK) {
2954		block = tcf_block_refcnt_get(net, tcm->tcm_block_index);
2955		if (!block)
2956			goto out;
 
 
 
 
 
 
 
2957	} else {
2958		const struct Qdisc_class_ops *cops;
2959		struct net_device *dev;
2960		unsigned long cl = 0;
2961
2962		dev = __dev_get_by_index(net, tcm->tcm_ifindex);
2963		if (!dev)
2964			return skb->len;
2965
2966		if (!tcm->tcm_parent)
 
2967			q = dev->qdisc;
2968		else
 
2969			q = qdisc_lookup(dev, TC_H_MAJ(tcm->tcm_parent));
2970
2971		if (!q)
2972			goto out;
2973		cops = q->ops->cl_ops;
2974		if (!cops)
2975			goto out;
2976		if (!cops->tcf_block)
2977			goto out;
2978		if (TC_H_MIN(tcm->tcm_parent)) {
2979			cl = cops->find(q, tcm->tcm_parent);
2980			if (cl == 0)
2981				goto out;
2982		}
2983		block = cops->tcf_block(q, cl, NULL);
2984		if (!block)
2985			goto out;
2986		if (tcf_block_shared(block))
2987			q = NULL;
2988	}
2989
2990	index_start = cb->args[0];
2991	index = 0;
2992
2993	mutex_lock(&block->lock);
2994	list_for_each_entry(chain, &block->chain_list, list) {
2995		if ((tca[TCA_CHAIN] &&
2996		     nla_get_u32(tca[TCA_CHAIN]) != chain->index))
2997			continue;
2998		if (index < index_start) {
2999			index++;
3000			continue;
3001		}
3002		if (tcf_chain_held_by_acts_only(chain))
3003			continue;
3004		err = tc_chain_fill_node(chain->tmplt_ops, chain->tmplt_priv,
3005					 chain->index, net, skb, block,
3006					 NETLINK_CB(cb->skb).portid,
3007					 cb->nlh->nlmsg_seq, NLM_F_MULTI,
3008					 RTM_NEWCHAIN);
3009		if (err <= 0)
3010			break;
3011		index++;
3012	}
3013	mutex_unlock(&block->lock);
3014
3015	if (tcm->tcm_ifindex == TCM_IFINDEX_MAGIC_BLOCK)
3016		tcf_block_refcnt_put(block, true);
3017	cb->args[0] = index;
3018
3019out:
3020	/* If we did no progress, the error (EMSGSIZE) is real */
3021	if (skb->len == 0 && err)
3022		return err;
3023	return skb->len;
3024}
3025
3026void tcf_exts_destroy(struct tcf_exts *exts)
3027{
3028#ifdef CONFIG_NET_CLS_ACT
3029	if (exts->actions) {
3030		tcf_action_destroy(exts->actions, TCA_ACT_UNBIND);
3031		kfree(exts->actions);
3032	}
3033	exts->nr_actions = 0;
3034#endif
3035}
3036EXPORT_SYMBOL(tcf_exts_destroy);
3037
3038int tcf_exts_validate(struct net *net, struct tcf_proto *tp, struct nlattr **tb,
3039		      struct nlattr *rate_tlv, struct tcf_exts *exts, bool ovr,
3040		      bool rtnl_held, struct netlink_ext_ack *extack)
3041{
3042#ifdef CONFIG_NET_CLS_ACT
3043	{
3044		int init_res[TCA_ACT_MAX_PRIO] = {};
3045		struct tc_action *act;
3046		size_t attr_size = 0;
3047
3048		if (exts->police && tb[exts->police]) {
3049			struct tc_action_ops *a_o;
3050
3051			a_o = tc_action_load_ops("police", tb[exts->police], rtnl_held, extack);
3052			if (IS_ERR(a_o))
3053				return PTR_ERR(a_o);
3054			act = tcf_action_init_1(net, tp, tb[exts->police],
3055						rate_tlv, "police", ovr,
3056						TCA_ACT_BIND, a_o, init_res,
3057						rtnl_held, extack);
3058			module_put(a_o->owner);
3059			if (IS_ERR(act))
3060				return PTR_ERR(act);
3061
3062			act->type = exts->type = TCA_OLD_COMPAT;
3063			exts->actions[0] = act;
3064			exts->nr_actions = 1;
3065			tcf_idr_insert_many(exts->actions);
3066		} else if (exts->action && tb[exts->action]) {
3067			int err;
3068
3069			err = tcf_action_init(net, tp, tb[exts->action],
3070					      rate_tlv, NULL, ovr, TCA_ACT_BIND,
3071					      exts->actions, init_res,
3072					      &attr_size, rtnl_held, extack);
3073			if (err < 0)
3074				return err;
3075			exts->nr_actions = err;
3076		}
3077	}
3078#else
3079	if ((exts->action && tb[exts->action]) ||
3080	    (exts->police && tb[exts->police])) {
3081		NL_SET_ERR_MSG(extack, "Classifier actions are not supported per compile options (CONFIG_NET_CLS_ACT)");
3082		return -EOPNOTSUPP;
3083	}
3084#endif
3085
3086	return 0;
3087}
3088EXPORT_SYMBOL(tcf_exts_validate);
3089
3090void tcf_exts_change(struct tcf_exts *dst, struct tcf_exts *src)
3091{
3092#ifdef CONFIG_NET_CLS_ACT
3093	struct tcf_exts old = *dst;
3094
3095	*dst = *src;
3096	tcf_exts_destroy(&old);
3097#endif
3098}
3099EXPORT_SYMBOL(tcf_exts_change);
3100
3101#ifdef CONFIG_NET_CLS_ACT
3102static struct tc_action *tcf_exts_first_act(struct tcf_exts *exts)
3103{
3104	if (exts->nr_actions == 0)
3105		return NULL;
3106	else
3107		return exts->actions[0];
3108}
3109#endif
3110
3111int tcf_exts_dump(struct sk_buff *skb, struct tcf_exts *exts)
3112{
3113#ifdef CONFIG_NET_CLS_ACT
3114	struct nlattr *nest;
3115
3116	if (exts->action && tcf_exts_has_actions(exts)) {
3117		/*
3118		 * again for backward compatible mode - we want
3119		 * to work with both old and new modes of entering
3120		 * tc data even if iproute2  was newer - jhs
3121		 */
3122		if (exts->type != TCA_OLD_COMPAT) {
3123			nest = nla_nest_start_noflag(skb, exts->action);
3124			if (nest == NULL)
3125				goto nla_put_failure;
3126
3127			if (tcf_action_dump(skb, exts->actions, 0, 0, false)
3128			    < 0)
3129				goto nla_put_failure;
3130			nla_nest_end(skb, nest);
3131		} else if (exts->police) {
3132			struct tc_action *act = tcf_exts_first_act(exts);
3133			nest = nla_nest_start_noflag(skb, exts->police);
3134			if (nest == NULL || !act)
3135				goto nla_put_failure;
3136			if (tcf_action_dump_old(skb, act, 0, 0) < 0)
3137				goto nla_put_failure;
3138			nla_nest_end(skb, nest);
3139		}
3140	}
3141	return 0;
3142
3143nla_put_failure:
3144	nla_nest_cancel(skb, nest);
3145	return -1;
3146#else
3147	return 0;
3148#endif
3149}
3150EXPORT_SYMBOL(tcf_exts_dump);
3151
3152int tcf_exts_terse_dump(struct sk_buff *skb, struct tcf_exts *exts)
3153{
3154#ifdef CONFIG_NET_CLS_ACT
3155	struct nlattr *nest;
3156
3157	if (!exts->action || !tcf_exts_has_actions(exts))
3158		return 0;
3159
3160	nest = nla_nest_start_noflag(skb, exts->action);
3161	if (!nest)
3162		goto nla_put_failure;
3163
3164	if (tcf_action_dump(skb, exts->actions, 0, 0, true) < 0)
3165		goto nla_put_failure;
3166	nla_nest_end(skb, nest);
3167	return 0;
3168
3169nla_put_failure:
3170	nla_nest_cancel(skb, nest);
3171	return -1;
3172#else
3173	return 0;
3174#endif
3175}
3176EXPORT_SYMBOL(tcf_exts_terse_dump);
3177
3178int tcf_exts_dump_stats(struct sk_buff *skb, struct tcf_exts *exts)
3179{
3180#ifdef CONFIG_NET_CLS_ACT
3181	struct tc_action *a = tcf_exts_first_act(exts);
3182	if (a != NULL && tcf_action_copy_stats(skb, a, 1) < 0)
3183		return -1;
3184#endif
3185	return 0;
3186}
3187EXPORT_SYMBOL(tcf_exts_dump_stats);
3188
3189static void tcf_block_offload_inc(struct tcf_block *block, u32 *flags)
3190{
3191	if (*flags & TCA_CLS_FLAGS_IN_HW)
3192		return;
3193	*flags |= TCA_CLS_FLAGS_IN_HW;
3194	atomic_inc(&block->offloadcnt);
3195}
3196
3197static void tcf_block_offload_dec(struct tcf_block *block, u32 *flags)
3198{
3199	if (!(*flags & TCA_CLS_FLAGS_IN_HW))
3200		return;
3201	*flags &= ~TCA_CLS_FLAGS_IN_HW;
3202	atomic_dec(&block->offloadcnt);
3203}
3204
3205static void tc_cls_offload_cnt_update(struct tcf_block *block,
3206				      struct tcf_proto *tp, u32 *cnt,
3207				      u32 *flags, u32 diff, bool add)
3208{
3209	lockdep_assert_held(&block->cb_lock);
3210
3211	spin_lock(&tp->lock);
3212	if (add) {
3213		if (!*cnt)
3214			tcf_block_offload_inc(block, flags);
3215		*cnt += diff;
3216	} else {
3217		*cnt -= diff;
3218		if (!*cnt)
3219			tcf_block_offload_dec(block, flags);
3220	}
3221	spin_unlock(&tp->lock);
3222}
3223
3224static void
3225tc_cls_offload_cnt_reset(struct tcf_block *block, struct tcf_proto *tp,
3226			 u32 *cnt, u32 *flags)
3227{
3228	lockdep_assert_held(&block->cb_lock);
3229
3230	spin_lock(&tp->lock);
3231	tcf_block_offload_dec(block, flags);
3232	*cnt = 0;
3233	spin_unlock(&tp->lock);
3234}
3235
3236static int
3237__tc_setup_cb_call(struct tcf_block *block, enum tc_setup_type type,
3238		   void *type_data, bool err_stop)
3239{
3240	struct flow_block_cb *block_cb;
3241	int ok_count = 0;
3242	int err;
3243
3244	list_for_each_entry(block_cb, &block->flow_block.cb_list, list) {
3245		err = block_cb->cb(type, type_data, block_cb->cb_priv);
3246		if (err) {
3247			if (err_stop)
3248				return err;
3249		} else {
3250			ok_count++;
3251		}
3252	}
3253	return ok_count;
3254}
3255
3256int tc_setup_cb_call(struct tcf_block *block, enum tc_setup_type type,
3257		     void *type_data, bool err_stop, bool rtnl_held)
3258{
3259	bool take_rtnl = READ_ONCE(block->lockeddevcnt) && !rtnl_held;
3260	int ok_count;
3261
3262retry:
3263	if (take_rtnl)
3264		rtnl_lock();
3265	down_read(&block->cb_lock);
3266	/* Need to obtain rtnl lock if block is bound to devs that require it.
3267	 * In block bind code cb_lock is obtained while holding rtnl, so we must
3268	 * obtain the locks in same order here.
3269	 */
3270	if (!rtnl_held && !take_rtnl && block->lockeddevcnt) {
3271		up_read(&block->cb_lock);
3272		take_rtnl = true;
3273		goto retry;
3274	}
3275
3276	ok_count = __tc_setup_cb_call(block, type, type_data, err_stop);
3277
3278	up_read(&block->cb_lock);
3279	if (take_rtnl)
3280		rtnl_unlock();
3281	return ok_count;
3282}
3283EXPORT_SYMBOL(tc_setup_cb_call);
3284
3285/* Non-destructive filter add. If filter that wasn't already in hardware is
3286 * successfully offloaded, increment block offloads counter. On failure,
3287 * previously offloaded filter is considered to be intact and offloads counter
3288 * is not decremented.
3289 */
3290
3291int tc_setup_cb_add(struct tcf_block *block, struct tcf_proto *tp,
3292		    enum tc_setup_type type, void *type_data, bool err_stop,
3293		    u32 *flags, unsigned int *in_hw_count, bool rtnl_held)
3294{
3295	bool take_rtnl = READ_ONCE(block->lockeddevcnt) && !rtnl_held;
3296	int ok_count;
3297
3298retry:
3299	if (take_rtnl)
3300		rtnl_lock();
3301	down_read(&block->cb_lock);
3302	/* Need to obtain rtnl lock if block is bound to devs that require it.
3303	 * In block bind code cb_lock is obtained while holding rtnl, so we must
3304	 * obtain the locks in same order here.
3305	 */
3306	if (!rtnl_held && !take_rtnl && block->lockeddevcnt) {
3307		up_read(&block->cb_lock);
3308		take_rtnl = true;
3309		goto retry;
3310	}
3311
3312	/* Make sure all netdevs sharing this block are offload-capable. */
3313	if (block->nooffloaddevcnt && err_stop) {
3314		ok_count = -EOPNOTSUPP;
3315		goto err_unlock;
3316	}
3317
3318	ok_count = __tc_setup_cb_call(block, type, type_data, err_stop);
3319	if (ok_count < 0)
3320		goto err_unlock;
3321
3322	if (tp->ops->hw_add)
3323		tp->ops->hw_add(tp, type_data);
3324	if (ok_count > 0)
3325		tc_cls_offload_cnt_update(block, tp, in_hw_count, flags,
3326					  ok_count, true);
3327err_unlock:
3328	up_read(&block->cb_lock);
3329	if (take_rtnl)
3330		rtnl_unlock();
3331	return ok_count < 0 ? ok_count : 0;
3332}
3333EXPORT_SYMBOL(tc_setup_cb_add);
3334
3335/* Destructive filter replace. If filter that wasn't already in hardware is
3336 * successfully offloaded, increment block offload counter. On failure,
3337 * previously offloaded filter is considered to be destroyed and offload counter
3338 * is decremented.
3339 */
3340
3341int tc_setup_cb_replace(struct tcf_block *block, struct tcf_proto *tp,
3342			enum tc_setup_type type, void *type_data, bool err_stop,
3343			u32 *old_flags, unsigned int *old_in_hw_count,
3344			u32 *new_flags, unsigned int *new_in_hw_count,
3345			bool rtnl_held)
3346{
3347	bool take_rtnl = READ_ONCE(block->lockeddevcnt) && !rtnl_held;
3348	int ok_count;
3349
3350retry:
3351	if (take_rtnl)
3352		rtnl_lock();
3353	down_read(&block->cb_lock);
3354	/* Need to obtain rtnl lock if block is bound to devs that require it.
3355	 * In block bind code cb_lock is obtained while holding rtnl, so we must
3356	 * obtain the locks in same order here.
3357	 */
3358	if (!rtnl_held && !take_rtnl && block->lockeddevcnt) {
3359		up_read(&block->cb_lock);
3360		take_rtnl = true;
3361		goto retry;
3362	}
3363
3364	/* Make sure all netdevs sharing this block are offload-capable. */
3365	if (block->nooffloaddevcnt && err_stop) {
3366		ok_count = -EOPNOTSUPP;
3367		goto err_unlock;
3368	}
3369
3370	tc_cls_offload_cnt_reset(block, tp, old_in_hw_count, old_flags);
3371	if (tp->ops->hw_del)
3372		tp->ops->hw_del(tp, type_data);
3373
3374	ok_count = __tc_setup_cb_call(block, type, type_data, err_stop);
3375	if (ok_count < 0)
3376		goto err_unlock;
3377
3378	if (tp->ops->hw_add)
3379		tp->ops->hw_add(tp, type_data);
3380	if (ok_count > 0)
3381		tc_cls_offload_cnt_update(block, tp, new_in_hw_count,
3382					  new_flags, ok_count, true);
3383err_unlock:
3384	up_read(&block->cb_lock);
3385	if (take_rtnl)
3386		rtnl_unlock();
3387	return ok_count < 0 ? ok_count : 0;
3388}
3389EXPORT_SYMBOL(tc_setup_cb_replace);
3390
3391/* Destroy filter and decrement block offload counter, if filter was previously
3392 * offloaded.
3393 */
3394
3395int tc_setup_cb_destroy(struct tcf_block *block, struct tcf_proto *tp,
3396			enum tc_setup_type type, void *type_data, bool err_stop,
3397			u32 *flags, unsigned int *in_hw_count, bool rtnl_held)
3398{
3399	bool take_rtnl = READ_ONCE(block->lockeddevcnt) && !rtnl_held;
3400	int ok_count;
3401
3402retry:
3403	if (take_rtnl)
3404		rtnl_lock();
3405	down_read(&block->cb_lock);
3406	/* Need to obtain rtnl lock if block is bound to devs that require it.
3407	 * In block bind code cb_lock is obtained while holding rtnl, so we must
3408	 * obtain the locks in same order here.
3409	 */
3410	if (!rtnl_held && !take_rtnl && block->lockeddevcnt) {
3411		up_read(&block->cb_lock);
3412		take_rtnl = true;
3413		goto retry;
3414	}
3415
3416	ok_count = __tc_setup_cb_call(block, type, type_data, err_stop);
3417
3418	tc_cls_offload_cnt_reset(block, tp, in_hw_count, flags);
3419	if (tp->ops->hw_del)
3420		tp->ops->hw_del(tp, type_data);
3421
3422	up_read(&block->cb_lock);
3423	if (take_rtnl)
3424		rtnl_unlock();
3425	return ok_count < 0 ? ok_count : 0;
3426}
3427EXPORT_SYMBOL(tc_setup_cb_destroy);
3428
3429int tc_setup_cb_reoffload(struct tcf_block *block, struct tcf_proto *tp,
3430			  bool add, flow_setup_cb_t *cb,
3431			  enum tc_setup_type type, void *type_data,
3432			  void *cb_priv, u32 *flags, unsigned int *in_hw_count)
3433{
3434	int err = cb(type, type_data, cb_priv);
3435
3436	if (err) {
3437		if (add && tc_skip_sw(*flags))
3438			return err;
3439	} else {
3440		tc_cls_offload_cnt_update(block, tp, in_hw_count, flags, 1,
3441					  add);
3442	}
3443
3444	return 0;
3445}
3446EXPORT_SYMBOL(tc_setup_cb_reoffload);
3447
3448static int tcf_act_get_cookie(struct flow_action_entry *entry,
3449			      const struct tc_action *act)
3450{
3451	struct tc_cookie *cookie;
3452	int err = 0;
3453
3454	rcu_read_lock();
3455	cookie = rcu_dereference(act->act_cookie);
3456	if (cookie) {
3457		entry->cookie = flow_action_cookie_create(cookie->data,
3458							  cookie->len,
3459							  GFP_ATOMIC);
3460		if (!entry->cookie)
3461			err = -ENOMEM;
3462	}
3463	rcu_read_unlock();
3464	return err;
3465}
3466
3467static void tcf_act_put_cookie(struct flow_action_entry *entry)
3468{
3469	flow_action_cookie_destroy(entry->cookie);
3470}
3471
3472void tc_cleanup_flow_action(struct flow_action *flow_action)
3473{
3474	struct flow_action_entry *entry;
3475	int i;
3476
3477	flow_action_for_each(i, entry, flow_action) {
3478		tcf_act_put_cookie(entry);
3479		if (entry->destructor)
3480			entry->destructor(entry->destructor_priv);
3481	}
3482}
3483EXPORT_SYMBOL(tc_cleanup_flow_action);
3484
3485static void tcf_mirred_get_dev(struct flow_action_entry *entry,
3486			       const struct tc_action *act)
3487{
3488#ifdef CONFIG_NET_CLS_ACT
3489	entry->dev = act->ops->get_dev(act, &entry->destructor);
3490	if (!entry->dev)
3491		return;
3492	entry->destructor_priv = entry->dev;
3493#endif
3494}
3495
3496static void tcf_tunnel_encap_put_tunnel(void *priv)
3497{
3498	struct ip_tunnel_info *tunnel = priv;
3499
3500	kfree(tunnel);
3501}
3502
3503static int tcf_tunnel_encap_get_tunnel(struct flow_action_entry *entry,
3504				       const struct tc_action *act)
3505{
3506	entry->tunnel = tcf_tunnel_info_copy(act);
3507	if (!entry->tunnel)
3508		return -ENOMEM;
3509	entry->destructor = tcf_tunnel_encap_put_tunnel;
3510	entry->destructor_priv = entry->tunnel;
3511	return 0;
3512}
3513
3514static void tcf_sample_get_group(struct flow_action_entry *entry,
3515				 const struct tc_action *act)
3516{
3517#ifdef CONFIG_NET_CLS_ACT
3518	entry->sample.psample_group =
3519		act->ops->get_psample_group(act, &entry->destructor);
3520	entry->destructor_priv = entry->sample.psample_group;
3521#endif
3522}
3523
3524static void tcf_gate_entry_destructor(void *priv)
3525{
3526	struct action_gate_entry *oe = priv;
3527
3528	kfree(oe);
3529}
3530
3531static int tcf_gate_get_entries(struct flow_action_entry *entry,
3532				const struct tc_action *act)
3533{
3534	entry->gate.entries = tcf_gate_get_list(act);
3535
3536	if (!entry->gate.entries)
3537		return -EINVAL;
3538
3539	entry->destructor = tcf_gate_entry_destructor;
3540	entry->destructor_priv = entry->gate.entries;
3541
3542	return 0;
3543}
3544
3545static enum flow_action_hw_stats tc_act_hw_stats(u8 hw_stats)
3546{
3547	if (WARN_ON_ONCE(hw_stats > TCA_ACT_HW_STATS_ANY))
3548		return FLOW_ACTION_HW_STATS_DONT_CARE;
3549	else if (!hw_stats)
3550		return FLOW_ACTION_HW_STATS_DISABLED;
3551
3552	return hw_stats;
3553}
3554
3555int tc_setup_flow_action(struct flow_action *flow_action,
3556			 const struct tcf_exts *exts)
3557{
3558	struct tc_action *act;
3559	int i, j, k, err = 0;
3560
3561	BUILD_BUG_ON(TCA_ACT_HW_STATS_ANY != FLOW_ACTION_HW_STATS_ANY);
3562	BUILD_BUG_ON(TCA_ACT_HW_STATS_IMMEDIATE != FLOW_ACTION_HW_STATS_IMMEDIATE);
3563	BUILD_BUG_ON(TCA_ACT_HW_STATS_DELAYED != FLOW_ACTION_HW_STATS_DELAYED);
3564
3565	if (!exts)
3566		return 0;
3567
 
 
 
3568	j = 0;
3569	tcf_exts_for_each_action(i, act, exts) {
3570		struct flow_action_entry *entry;
3571
3572		entry = &flow_action->entries[j];
3573		spin_lock_bh(&act->tcfa_lock);
3574		err = tcf_act_get_cookie(entry, act);
3575		if (err)
3576			goto err_out_locked;
3577
3578		entry->hw_stats = tc_act_hw_stats(act->hw_stats);
3579
3580		if (is_tcf_gact_ok(act)) {
3581			entry->id = FLOW_ACTION_ACCEPT;
3582		} else if (is_tcf_gact_shot(act)) {
3583			entry->id = FLOW_ACTION_DROP;
3584		} else if (is_tcf_gact_trap(act)) {
3585			entry->id = FLOW_ACTION_TRAP;
3586		} else if (is_tcf_gact_goto_chain(act)) {
3587			entry->id = FLOW_ACTION_GOTO;
3588			entry->chain_index = tcf_gact_goto_chain_index(act);
3589		} else if (is_tcf_mirred_egress_redirect(act)) {
3590			entry->id = FLOW_ACTION_REDIRECT;
3591			tcf_mirred_get_dev(entry, act);
3592		} else if (is_tcf_mirred_egress_mirror(act)) {
3593			entry->id = FLOW_ACTION_MIRRED;
3594			tcf_mirred_get_dev(entry, act);
3595		} else if (is_tcf_mirred_ingress_redirect(act)) {
3596			entry->id = FLOW_ACTION_REDIRECT_INGRESS;
3597			tcf_mirred_get_dev(entry, act);
3598		} else if (is_tcf_mirred_ingress_mirror(act)) {
3599			entry->id = FLOW_ACTION_MIRRED_INGRESS;
3600			tcf_mirred_get_dev(entry, act);
3601		} else if (is_tcf_vlan(act)) {
3602			switch (tcf_vlan_action(act)) {
3603			case TCA_VLAN_ACT_PUSH:
3604				entry->id = FLOW_ACTION_VLAN_PUSH;
3605				entry->vlan.vid = tcf_vlan_push_vid(act);
3606				entry->vlan.proto = tcf_vlan_push_proto(act);
3607				entry->vlan.prio = tcf_vlan_push_prio(act);
3608				break;
3609			case TCA_VLAN_ACT_POP:
3610				entry->id = FLOW_ACTION_VLAN_POP;
3611				break;
3612			case TCA_VLAN_ACT_MODIFY:
3613				entry->id = FLOW_ACTION_VLAN_MANGLE;
3614				entry->vlan.vid = tcf_vlan_push_vid(act);
3615				entry->vlan.proto = tcf_vlan_push_proto(act);
3616				entry->vlan.prio = tcf_vlan_push_prio(act);
3617				break;
3618			default:
3619				err = -EOPNOTSUPP;
3620				goto err_out_locked;
3621			}
3622		} else if (is_tcf_tunnel_set(act)) {
3623			entry->id = FLOW_ACTION_TUNNEL_ENCAP;
3624			err = tcf_tunnel_encap_get_tunnel(entry, act);
3625			if (err)
3626				goto err_out_locked;
3627		} else if (is_tcf_tunnel_release(act)) {
3628			entry->id = FLOW_ACTION_TUNNEL_DECAP;
3629		} else if (is_tcf_pedit(act)) {
3630			for (k = 0; k < tcf_pedit_nkeys(act); k++) {
3631				switch (tcf_pedit_cmd(act, k)) {
3632				case TCA_PEDIT_KEY_EX_CMD_SET:
3633					entry->id = FLOW_ACTION_MANGLE;
3634					break;
3635				case TCA_PEDIT_KEY_EX_CMD_ADD:
3636					entry->id = FLOW_ACTION_ADD;
3637					break;
3638				default:
3639					err = -EOPNOTSUPP;
3640					goto err_out_locked;
3641				}
3642				entry->mangle.htype = tcf_pedit_htype(act, k);
3643				entry->mangle.mask = tcf_pedit_mask(act, k);
3644				entry->mangle.val = tcf_pedit_val(act, k);
3645				entry->mangle.offset = tcf_pedit_offset(act, k);
3646				entry->hw_stats = tc_act_hw_stats(act->hw_stats);
3647				entry = &flow_action->entries[++j];
3648			}
3649		} else if (is_tcf_csum(act)) {
3650			entry->id = FLOW_ACTION_CSUM;
3651			entry->csum_flags = tcf_csum_update_flags(act);
3652		} else if (is_tcf_skbedit_mark(act)) {
3653			entry->id = FLOW_ACTION_MARK;
3654			entry->mark = tcf_skbedit_mark(act);
3655		} else if (is_tcf_sample(act)) {
3656			entry->id = FLOW_ACTION_SAMPLE;
3657			entry->sample.trunc_size = tcf_sample_trunc_size(act);
3658			entry->sample.truncate = tcf_sample_truncate(act);
3659			entry->sample.rate = tcf_sample_rate(act);
3660			tcf_sample_get_group(entry, act);
3661		} else if (is_tcf_police(act)) {
3662			entry->id = FLOW_ACTION_POLICE;
3663			entry->police.burst = tcf_police_burst(act);
3664			entry->police.rate_bytes_ps =
3665				tcf_police_rate_bytes_ps(act);
3666			entry->police.burst_pkt = tcf_police_burst_pkt(act);
3667			entry->police.rate_pkt_ps =
3668				tcf_police_rate_pkt_ps(act);
3669			entry->police.mtu = tcf_police_tcfp_mtu(act);
3670			entry->police.index = act->tcfa_index;
3671		} else if (is_tcf_ct(act)) {
3672			entry->id = FLOW_ACTION_CT;
3673			entry->ct.action = tcf_ct_action(act);
3674			entry->ct.zone = tcf_ct_zone(act);
3675			entry->ct.flow_table = tcf_ct_ft(act);
3676		} else if (is_tcf_mpls(act)) {
3677			switch (tcf_mpls_action(act)) {
3678			case TCA_MPLS_ACT_PUSH:
3679				entry->id = FLOW_ACTION_MPLS_PUSH;
3680				entry->mpls_push.proto = tcf_mpls_proto(act);
3681				entry->mpls_push.label = tcf_mpls_label(act);
3682				entry->mpls_push.tc = tcf_mpls_tc(act);
3683				entry->mpls_push.bos = tcf_mpls_bos(act);
3684				entry->mpls_push.ttl = tcf_mpls_ttl(act);
3685				break;
3686			case TCA_MPLS_ACT_POP:
3687				entry->id = FLOW_ACTION_MPLS_POP;
3688				entry->mpls_pop.proto = tcf_mpls_proto(act);
3689				break;
3690			case TCA_MPLS_ACT_MODIFY:
3691				entry->id = FLOW_ACTION_MPLS_MANGLE;
3692				entry->mpls_mangle.label = tcf_mpls_label(act);
3693				entry->mpls_mangle.tc = tcf_mpls_tc(act);
3694				entry->mpls_mangle.bos = tcf_mpls_bos(act);
3695				entry->mpls_mangle.ttl = tcf_mpls_ttl(act);
3696				break;
3697			default:
3698				goto err_out_locked;
3699			}
3700		} else if (is_tcf_skbedit_ptype(act)) {
3701			entry->id = FLOW_ACTION_PTYPE;
3702			entry->ptype = tcf_skbedit_ptype(act);
3703		} else if (is_tcf_skbedit_priority(act)) {
3704			entry->id = FLOW_ACTION_PRIORITY;
3705			entry->priority = tcf_skbedit_priority(act);
3706		} else if (is_tcf_gate(act)) {
3707			entry->id = FLOW_ACTION_GATE;
3708			entry->gate.index = tcf_gate_index(act);
3709			entry->gate.prio = tcf_gate_prio(act);
3710			entry->gate.basetime = tcf_gate_basetime(act);
3711			entry->gate.cycletime = tcf_gate_cycletime(act);
3712			entry->gate.cycletimeext = tcf_gate_cycletimeext(act);
3713			entry->gate.num_entries = tcf_gate_num_entries(act);
3714			err = tcf_gate_get_entries(entry, act);
3715			if (err)
3716				goto err_out_locked;
3717		} else {
3718			err = -EOPNOTSUPP;
3719			goto err_out_locked;
3720		}
3721		spin_unlock_bh(&act->tcfa_lock);
3722
3723		if (!is_tcf_pedit(act))
3724			j++;
3725	}
3726
3727err_out:
 
 
 
3728	if (err)
3729		tc_cleanup_flow_action(flow_action);
3730
3731	return err;
3732err_out_locked:
3733	spin_unlock_bh(&act->tcfa_lock);
3734	goto err_out;
3735}
3736EXPORT_SYMBOL(tc_setup_flow_action);
3737
3738unsigned int tcf_exts_num_actions(struct tcf_exts *exts)
3739{
3740	unsigned int num_acts = 0;
3741	struct tc_action *act;
3742	int i;
3743
3744	tcf_exts_for_each_action(i, act, exts) {
3745		if (is_tcf_pedit(act))
3746			num_acts += tcf_pedit_nkeys(act);
3747		else
3748			num_acts++;
3749	}
3750	return num_acts;
3751}
3752EXPORT_SYMBOL(tcf_exts_num_actions);
3753
3754#ifdef CONFIG_NET_CLS_ACT
3755static int tcf_qevent_parse_block_index(struct nlattr *block_index_attr,
3756					u32 *p_block_index,
3757					struct netlink_ext_ack *extack)
3758{
3759	*p_block_index = nla_get_u32(block_index_attr);
3760	if (!*p_block_index) {
3761		NL_SET_ERR_MSG(extack, "Block number may not be zero");
3762		return -EINVAL;
3763	}
3764
3765	return 0;
3766}
3767
3768int tcf_qevent_init(struct tcf_qevent *qe, struct Qdisc *sch,
3769		    enum flow_block_binder_type binder_type,
3770		    struct nlattr *block_index_attr,
3771		    struct netlink_ext_ack *extack)
3772{
3773	u32 block_index;
3774	int err;
3775
3776	if (!block_index_attr)
3777		return 0;
3778
3779	err = tcf_qevent_parse_block_index(block_index_attr, &block_index, extack);
3780	if (err)
3781		return err;
3782
3783	if (!block_index)
3784		return 0;
3785
3786	qe->info.binder_type = binder_type;
3787	qe->info.chain_head_change = tcf_chain_head_change_dflt;
3788	qe->info.chain_head_change_priv = &qe->filter_chain;
3789	qe->info.block_index = block_index;
3790
3791	return tcf_block_get_ext(&qe->block, sch, &qe->info, extack);
3792}
3793EXPORT_SYMBOL(tcf_qevent_init);
3794
3795void tcf_qevent_destroy(struct tcf_qevent *qe, struct Qdisc *sch)
3796{
3797	if (qe->info.block_index)
3798		tcf_block_put_ext(qe->block, sch, &qe->info);
3799}
3800EXPORT_SYMBOL(tcf_qevent_destroy);
3801
3802int tcf_qevent_validate_change(struct tcf_qevent *qe, struct nlattr *block_index_attr,
3803			       struct netlink_ext_ack *extack)
3804{
3805	u32 block_index;
3806	int err;
3807
3808	if (!block_index_attr)
3809		return 0;
3810
3811	err = tcf_qevent_parse_block_index(block_index_attr, &block_index, extack);
3812	if (err)
3813		return err;
3814
3815	/* Bounce newly-configured block or change in block. */
3816	if (block_index != qe->info.block_index) {
3817		NL_SET_ERR_MSG(extack, "Change of blocks is not supported");
3818		return -EINVAL;
3819	}
3820
3821	return 0;
3822}
3823EXPORT_SYMBOL(tcf_qevent_validate_change);
3824
3825struct sk_buff *tcf_qevent_handle(struct tcf_qevent *qe, struct Qdisc *sch, struct sk_buff *skb,
3826				  struct sk_buff **to_free, int *ret)
3827{
3828	struct tcf_result cl_res;
3829	struct tcf_proto *fl;
3830
3831	if (!qe->info.block_index)
3832		return skb;
3833
3834	fl = rcu_dereference_bh(qe->filter_chain);
3835
3836	switch (tcf_classify(skb, fl, &cl_res, false)) {
3837	case TC_ACT_SHOT:
3838		qdisc_qstats_drop(sch);
3839		__qdisc_drop(skb, to_free);
3840		*ret = __NET_XMIT_BYPASS;
3841		return NULL;
3842	case TC_ACT_STOLEN:
3843	case TC_ACT_QUEUED:
3844	case TC_ACT_TRAP:
3845		__qdisc_drop(skb, to_free);
3846		*ret = __NET_XMIT_STOLEN;
3847		return NULL;
3848	case TC_ACT_REDIRECT:
3849		skb_do_redirect(skb);
3850		*ret = __NET_XMIT_STOLEN;
3851		return NULL;
3852	}
3853
3854	return skb;
3855}
3856EXPORT_SYMBOL(tcf_qevent_handle);
3857
3858int tcf_qevent_dump(struct sk_buff *skb, int attr_name, struct tcf_qevent *qe)
3859{
3860	if (!qe->info.block_index)
3861		return 0;
3862	return nla_put_u32(skb, attr_name, qe->info.block_index);
3863}
3864EXPORT_SYMBOL(tcf_qevent_dump);
3865#endif
3866
3867static __net_init int tcf_net_init(struct net *net)
3868{
3869	struct tcf_net *tn = net_generic(net, tcf_net_id);
3870
3871	spin_lock_init(&tn->idr_lock);
3872	idr_init(&tn->idr);
3873	return 0;
3874}
3875
3876static void __net_exit tcf_net_exit(struct net *net)
3877{
3878	struct tcf_net *tn = net_generic(net, tcf_net_id);
3879
3880	idr_destroy(&tn->idr);
3881}
3882
3883static struct pernet_operations tcf_net_ops = {
3884	.init = tcf_net_init,
3885	.exit = tcf_net_exit,
3886	.id   = &tcf_net_id,
3887	.size = sizeof(struct tcf_net),
3888};
3889
 
 
 
 
 
3890static int __init tc_filter_init(void)
3891{
3892	int err;
3893
3894	tc_filter_wq = alloc_ordered_workqueue("tc_filter_workqueue", 0);
3895	if (!tc_filter_wq)
3896		return -ENOMEM;
3897
3898	err = register_pernet_subsys(&tcf_net_ops);
3899	if (err)
3900		goto err_register_pernet_subsys;
 
 
3901
3902	rtnl_register(PF_UNSPEC, RTM_NEWTFILTER, tc_new_tfilter, NULL,
3903		      RTNL_FLAG_DOIT_UNLOCKED);
3904	rtnl_register(PF_UNSPEC, RTM_DELTFILTER, tc_del_tfilter, NULL,
3905		      RTNL_FLAG_DOIT_UNLOCKED);
3906	rtnl_register(PF_UNSPEC, RTM_GETTFILTER, tc_get_tfilter,
3907		      tc_dump_tfilter, RTNL_FLAG_DOIT_UNLOCKED);
3908	rtnl_register(PF_UNSPEC, RTM_NEWCHAIN, tc_ctl_chain, NULL, 0);
3909	rtnl_register(PF_UNSPEC, RTM_DELCHAIN, tc_ctl_chain, NULL, 0);
3910	rtnl_register(PF_UNSPEC, RTM_GETCHAIN, tc_ctl_chain,
3911		      tc_dump_chain, 0);
3912
3913	return 0;
3914
3915err_register_pernet_subsys:
3916	destroy_workqueue(tc_filter_wq);
3917	return err;
3918}
3919
3920subsys_initcall(tc_filter_init);