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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);
v4.17
 
   1/*
   2 * net/sched/cls_api.c	Packet classifier API.
   3 *
   4 *		This program is free software; you can redistribute it and/or
   5 *		modify it under the terms of the GNU General Public License
   6 *		as published by the Free Software Foundation; either version
   7 *		2 of the License, or (at your option) any later version.
   8 *
   9 * Authors:	Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
  10 *
  11 * Changes:
  12 *
  13 * Eduardo J. Blanco <ejbs@netlabs.com.uy> :990222: kmod support
  14 *
  15 */
  16
  17#include <linux/module.h>
  18#include <linux/types.h>
  19#include <linux/kernel.h>
  20#include <linux/string.h>
  21#include <linux/errno.h>
  22#include <linux/err.h>
  23#include <linux/skbuff.h>
  24#include <linux/init.h>
  25#include <linux/kmod.h>
  26#include <linux/slab.h>
  27#include <linux/idr.h>
 
 
  28#include <net/net_namespace.h>
  29#include <net/sock.h>
  30#include <net/netlink.h>
  31#include <net/pkt_sched.h>
  32#include <net/pkt_cls.h>
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  33
  34/* The list of all installed classifier types */
  35static LIST_HEAD(tcf_proto_base);
  36
  37/* Protects list of registered TC modules. It is pure SMP lock. */
  38static DEFINE_RWLOCK(cls_mod_lock);
  39
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  40/* Find classifier type by string name */
  41
  42static const struct tcf_proto_ops *tcf_proto_lookup_ops(const char *kind)
  43{
  44	const struct tcf_proto_ops *t, *res = NULL;
  45
  46	if (kind) {
  47		read_lock(&cls_mod_lock);
  48		list_for_each_entry(t, &tcf_proto_base, head) {
  49			if (strcmp(kind, t->kind) == 0) {
  50				if (try_module_get(t->owner))
  51					res = t;
  52				break;
  53			}
  54		}
  55		read_unlock(&cls_mod_lock);
  56	}
  57	return res;
  58}
  59
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  60/* Register(unregister) new classifier type */
  61
  62int register_tcf_proto_ops(struct tcf_proto_ops *ops)
  63{
  64	struct tcf_proto_ops *t;
  65	int rc = -EEXIST;
  66
  67	write_lock(&cls_mod_lock);
  68	list_for_each_entry(t, &tcf_proto_base, head)
  69		if (!strcmp(ops->kind, t->kind))
  70			goto out;
  71
  72	list_add_tail(&ops->head, &tcf_proto_base);
  73	rc = 0;
  74out:
  75	write_unlock(&cls_mod_lock);
  76	return rc;
  77}
  78EXPORT_SYMBOL(register_tcf_proto_ops);
  79
  80static struct workqueue_struct *tc_filter_wq;
  81
  82int unregister_tcf_proto_ops(struct tcf_proto_ops *ops)
  83{
  84	struct tcf_proto_ops *t;
  85	int rc = -ENOENT;
  86
  87	/* Wait for outstanding call_rcu()s, if any, from a
  88	 * tcf_proto_ops's destroy() handler.
  89	 */
  90	rcu_barrier();
  91	flush_workqueue(tc_filter_wq);
  92
  93	write_lock(&cls_mod_lock);
  94	list_for_each_entry(t, &tcf_proto_base, head) {
  95		if (t == ops) {
  96			list_del(&t->head);
  97			rc = 0;
  98			break;
  99		}
 100	}
 101	write_unlock(&cls_mod_lock);
 102	return rc;
 103}
 104EXPORT_SYMBOL(unregister_tcf_proto_ops);
 105
 106bool tcf_queue_work(struct work_struct *work)
 107{
 108	return queue_work(tc_filter_wq, work);
 
 109}
 110EXPORT_SYMBOL(tcf_queue_work);
 111
 112/* Select new prio value from the range, managed by kernel. */
 113
 114static inline u32 tcf_auto_prio(struct tcf_proto *tp)
 115{
 116	u32 first = TC_H_MAKE(0xC0000000U, 0U);
 117
 118	if (tp)
 119		first = tp->prio - 1;
 120
 121	return TC_H_MAJ(first);
 122}
 123
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 124static struct tcf_proto *tcf_proto_create(const char *kind, u32 protocol,
 125					  u32 prio, struct tcf_chain *chain,
 
 126					  struct netlink_ext_ack *extack)
 127{
 128	struct tcf_proto *tp;
 129	int err;
 130
 131	tp = kzalloc(sizeof(*tp), GFP_KERNEL);
 132	if (!tp)
 133		return ERR_PTR(-ENOBUFS);
 134
 135	err = -ENOENT;
 136	tp->ops = tcf_proto_lookup_ops(kind);
 137	if (!tp->ops) {
 138#ifdef CONFIG_MODULES
 139		rtnl_unlock();
 140		request_module("cls_%s", kind);
 141		rtnl_lock();
 142		tp->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 (tp->ops) {
 149			module_put(tp->ops->owner);
 150			err = -EAGAIN;
 151		} else {
 152			NL_SET_ERR_MSG(extack, "TC classifier not found");
 153			err = -ENOENT;
 154		}
 155#endif
 156		goto errout;
 157	}
 158	tp->classify = tp->ops->classify;
 159	tp->protocol = protocol;
 160	tp->prio = prio;
 161	tp->chain = chain;
 
 
 162
 163	err = tp->ops->init(tp);
 164	if (err) {
 165		module_put(tp->ops->owner);
 166		goto errout;
 167	}
 168	return tp;
 169
 170errout:
 171	kfree(tp);
 172	return ERR_PTR(err);
 173}
 174
 175static void tcf_proto_destroy(struct tcf_proto *tp,
 176			      struct netlink_ext_ack *extack)
 
 
 
 
 
 
 
 177{
 178	tp->ops->destroy(tp, extack);
 
 
 
 179	module_put(tp->ops->owner);
 180	kfree_rcu(tp, rcu);
 181}
 182
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 183struct tcf_filter_chain_list_item {
 184	struct list_head list;
 185	tcf_chain_head_change_t *chain_head_change;
 186	void *chain_head_change_priv;
 187};
 188
 189static struct tcf_chain *tcf_chain_create(struct tcf_block *block,
 190					  u32 chain_index)
 191{
 192	struct tcf_chain *chain;
 193
 
 
 194	chain = kzalloc(sizeof(*chain), GFP_KERNEL);
 195	if (!chain)
 196		return NULL;
 197	INIT_LIST_HEAD(&chain->filter_chain_list);
 198	list_add_tail(&chain->list, &block->chain_list);
 
 199	chain->block = block;
 200	chain->index = chain_index;
 201	chain->refcnt = 1;
 
 
 202	return chain;
 203}
 204
 205static void tcf_chain_head_change_item(struct tcf_filter_chain_list_item *item,
 206				       struct tcf_proto *tp_head)
 207{
 208	if (item->chain_head_change)
 209		item->chain_head_change(tp_head, item->chain_head_change_priv);
 210}
 211static void tcf_chain_head_change(struct tcf_chain *chain,
 212				  struct tcf_proto *tp_head)
 
 213{
 214	struct tcf_filter_chain_list_item *item;
 
 215
 216	list_for_each_entry(item, &chain->filter_chain_list, list)
 
 
 
 
 217		tcf_chain_head_change_item(item, tp_head);
 
 218}
 219
 220static void tcf_chain_flush(struct tcf_chain *chain)
 
 
 221{
 222	struct tcf_proto *tp = rtnl_dereference(chain->filter_chain);
 223
 224	tcf_chain_head_change(chain, NULL);
 225	while (tp) {
 226		RCU_INIT_POINTER(chain->filter_chain, tp->next);
 227		tcf_proto_destroy(tp, NULL);
 228		tp = rtnl_dereference(chain->filter_chain);
 229		tcf_chain_put(chain);
 230	}
 
 
 
 
 
 
 
 
 
 
 
 231}
 232
 233static void tcf_chain_destroy(struct tcf_chain *chain)
 234{
 235	struct tcf_block *block = chain->block;
 236
 237	list_del(&chain->list);
 238	kfree(chain);
 239	if (list_empty(&block->chain_list))
 240		kfree(block);
 241}
 242
 243static void tcf_chain_hold(struct tcf_chain *chain)
 244{
 
 
 245	++chain->refcnt;
 246}
 247
 248struct tcf_chain *tcf_chain_get(struct tcf_block *block, u32 chain_index,
 249				bool create)
 
 
 
 
 
 
 
 
 
 
 250{
 251	struct tcf_chain *chain;
 252
 
 
 253	list_for_each_entry(chain, &block->chain_list, list) {
 254		if (chain->index == chain_index) {
 255			tcf_chain_hold(chain);
 256			return chain;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 257		}
 
 258	}
 259
 260	return create ? tcf_chain_create(block, chain_index) : NULL;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 261}
 262EXPORT_SYMBOL(tcf_chain_get);
 263
 264void tcf_chain_put(struct tcf_chain *chain)
 265{
 266	if (--chain->refcnt == 0)
 267		tcf_chain_destroy(chain);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 268}
 269EXPORT_SYMBOL(tcf_chain_put);
 270
 271static bool tcf_block_offload_in_use(struct tcf_block *block)
 272{
 273	return block->offloadcnt;
 274}
 275
 276static int tcf_block_offload_cmd(struct tcf_block *block,
 277				 struct net_device *dev,
 278				 struct tcf_block_ext_info *ei,
 279				 enum tc_block_command command)
 
 280{
 281	struct tc_block_offload bo = {};
 
 282
 
 283	bo.command = command;
 284	bo.binder_type = ei->binder_type;
 285	bo.block = block;
 286	return dev->netdev_ops->ndo_setup_tc(dev, TC_SETUP_BLOCK, &bo);
 
 
 
 
 
 
 
 
 287}
 288
 289static int tcf_block_offload_bind(struct tcf_block *block, struct Qdisc *q,
 290				  struct tcf_block_ext_info *ei)
 
 291{
 292	struct net_device *dev = q->dev_queue->dev;
 293	int err;
 294
 
 295	if (!dev->netdev_ops->ndo_setup_tc)
 296		goto no_offload_dev_inc;
 297
 298	/* If tc offload feature is disabled and the block we try to bind
 299	 * to already has some offloaded filters, forbid to bind.
 300	 */
 301	if (!tc_can_offload(dev) && tcf_block_offload_in_use(block))
 302		return -EOPNOTSUPP;
 
 
 
 303
 304	err = tcf_block_offload_cmd(block, dev, ei, TC_BLOCK_BIND);
 305	if (err == -EOPNOTSUPP)
 306		goto no_offload_dev_inc;
 307	return err;
 
 
 
 
 
 308
 309no_offload_dev_inc:
 310	if (tcf_block_offload_in_use(block))
 311		return -EOPNOTSUPP;
 
 
 
 312	block->nooffloaddevcnt++;
 313	return 0;
 
 
 
 314}
 315
 316static void tcf_block_offload_unbind(struct tcf_block *block, struct Qdisc *q,
 317				     struct tcf_block_ext_info *ei)
 318{
 319	struct net_device *dev = q->dev_queue->dev;
 320	int err;
 321
 
 
 
 322	if (!dev->netdev_ops->ndo_setup_tc)
 323		goto no_offload_dev_dec;
 324	err = tcf_block_offload_cmd(block, dev, ei, TC_BLOCK_UNBIND);
 325	if (err == -EOPNOTSUPP)
 326		goto no_offload_dev_dec;
 
 327	return;
 328
 329no_offload_dev_dec:
 330	WARN_ON(block->nooffloaddevcnt-- == 0);
 
 331}
 332
 333static int
 334tcf_chain_head_change_cb_add(struct tcf_chain *chain,
 335			     struct tcf_block_ext_info *ei,
 336			     struct netlink_ext_ack *extack)
 337{
 338	struct tcf_filter_chain_list_item *item;
 
 339
 340	item = kmalloc(sizeof(*item), GFP_KERNEL);
 341	if (!item) {
 342		NL_SET_ERR_MSG(extack, "Memory allocation for head change callback item failed");
 343		return -ENOMEM;
 344	}
 345	item->chain_head_change = ei->chain_head_change;
 346	item->chain_head_change_priv = ei->chain_head_change_priv;
 347	if (chain->filter_chain)
 348		tcf_chain_head_change_item(item, chain->filter_chain);
 349	list_add(&item->list, &chain->filter_chain_list);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 350	return 0;
 351}
 352
 353static void
 354tcf_chain_head_change_cb_del(struct tcf_chain *chain,
 355			     struct tcf_block_ext_info *ei)
 356{
 357	struct tcf_filter_chain_list_item *item;
 358
 359	list_for_each_entry(item, &chain->filter_chain_list, list) {
 
 360		if ((!ei->chain_head_change && !ei->chain_head_change_priv) ||
 361		    (item->chain_head_change == ei->chain_head_change &&
 362		     item->chain_head_change_priv == ei->chain_head_change_priv)) {
 363			tcf_chain_head_change_item(item, NULL);
 
 364			list_del(&item->list);
 
 
 365			kfree(item);
 366			return;
 367		}
 368	}
 
 369	WARN_ON(1);
 370}
 371
 372struct tcf_net {
 
 373	struct idr idr;
 374};
 375
 376static unsigned int tcf_net_id;
 377
 378static int tcf_block_insert(struct tcf_block *block, struct net *net,
 379			    struct netlink_ext_ack *extack)
 380{
 381	struct tcf_net *tn = net_generic(net, tcf_net_id);
 
 382
 383	return idr_alloc_u32(&tn->idr, block, &block->index, block->index,
 384			     GFP_KERNEL);
 
 
 
 
 
 
 385}
 386
 387static void tcf_block_remove(struct tcf_block *block, struct net *net)
 388{
 389	struct tcf_net *tn = net_generic(net, tcf_net_id);
 390
 
 391	idr_remove(&tn->idr, block->index);
 
 392}
 393
 394static struct tcf_block *tcf_block_create(struct net *net, struct Qdisc *q,
 395					  u32 block_index,
 396					  struct netlink_ext_ack *extack)
 397{
 398	struct tcf_block *block;
 399	struct tcf_chain *chain;
 400	int err;
 401
 402	block = kzalloc(sizeof(*block), GFP_KERNEL);
 403	if (!block) {
 404		NL_SET_ERR_MSG(extack, "Memory allocation for block failed");
 405		return ERR_PTR(-ENOMEM);
 406	}
 
 
 
 
 407	INIT_LIST_HEAD(&block->chain_list);
 408	INIT_LIST_HEAD(&block->cb_list);
 409	INIT_LIST_HEAD(&block->owner_list);
 
 410
 411	/* Create chain 0 by default, it has to be always present. */
 412	chain = tcf_chain_create(block, 0);
 413	if (!chain) {
 414		NL_SET_ERR_MSG(extack, "Failed to create new tcf chain");
 415		err = -ENOMEM;
 416		goto err_chain_create;
 417	}
 418	block->refcnt = 1;
 419	block->net = net;
 420	block->index = block_index;
 421
 422	/* Don't store q pointer for blocks which are shared */
 423	if (!tcf_block_shared(block))
 424		block->q = q;
 425	return block;
 426
 427err_chain_create:
 428	kfree(block);
 429	return ERR_PTR(err);
 430}
 431
 432static struct tcf_block *tcf_block_lookup(struct net *net, u32 block_index)
 433{
 434	struct tcf_net *tn = net_generic(net, tcf_net_id);
 435
 436	return idr_find(&tn->idr, block_index);
 437}
 438
 439static struct tcf_chain *tcf_block_chain_zero(struct tcf_block *block)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 440{
 441	return list_first_entry(&block->chain_list, struct tcf_chain, list);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 442}
 443
 444struct tcf_block_owner_item {
 445	struct list_head list;
 446	struct Qdisc *q;
 447	enum tcf_block_binder_type binder_type;
 448};
 449
 450static void
 451tcf_block_owner_netif_keep_dst(struct tcf_block *block,
 452			       struct Qdisc *q,
 453			       enum tcf_block_binder_type binder_type)
 454{
 455	if (block->keep_dst &&
 456	    binder_type != TCF_BLOCK_BINDER_TYPE_CLSACT_INGRESS &&
 457	    binder_type != TCF_BLOCK_BINDER_TYPE_CLSACT_EGRESS)
 458		netif_keep_dst(qdisc_dev(q));
 459}
 460
 461void tcf_block_netif_keep_dst(struct tcf_block *block)
 462{
 463	struct tcf_block_owner_item *item;
 464
 465	block->keep_dst = true;
 466	list_for_each_entry(item, &block->owner_list, list)
 467		tcf_block_owner_netif_keep_dst(block, item->q,
 468					       item->binder_type);
 469}
 470EXPORT_SYMBOL(tcf_block_netif_keep_dst);
 471
 472static int tcf_block_owner_add(struct tcf_block *block,
 473			       struct Qdisc *q,
 474			       enum tcf_block_binder_type binder_type)
 475{
 476	struct tcf_block_owner_item *item;
 477
 478	item = kmalloc(sizeof(*item), GFP_KERNEL);
 479	if (!item)
 480		return -ENOMEM;
 481	item->q = q;
 482	item->binder_type = binder_type;
 483	list_add(&item->list, &block->owner_list);
 484	return 0;
 485}
 486
 487static void tcf_block_owner_del(struct tcf_block *block,
 488				struct Qdisc *q,
 489				enum tcf_block_binder_type binder_type)
 490{
 491	struct tcf_block_owner_item *item;
 492
 493	list_for_each_entry(item, &block->owner_list, list) {
 494		if (item->q == q && item->binder_type == binder_type) {
 495			list_del(&item->list);
 496			kfree(item);
 497			return;
 498		}
 499	}
 500	WARN_ON(1);
 501}
 502
 503int tcf_block_get_ext(struct tcf_block **p_block, struct Qdisc *q,
 504		      struct tcf_block_ext_info *ei,
 505		      struct netlink_ext_ack *extack)
 506{
 507	struct net *net = qdisc_net(q);
 508	struct tcf_block *block = NULL;
 509	bool created = false;
 510	int err;
 511
 512	if (ei->block_index) {
 513		/* block_index not 0 means the shared block is requested */
 514		block = tcf_block_lookup(net, ei->block_index);
 515		if (block)
 516			block->refcnt++;
 517	}
 518
 519	if (!block) {
 520		block = tcf_block_create(net, q, ei->block_index, extack);
 521		if (IS_ERR(block))
 522			return PTR_ERR(block);
 523		created = true;
 524		if (tcf_block_shared(block)) {
 525			err = tcf_block_insert(block, net, extack);
 526			if (err)
 527				goto err_block_insert;
 528		}
 529	}
 530
 531	err = tcf_block_owner_add(block, q, ei->binder_type);
 532	if (err)
 533		goto err_block_owner_add;
 534
 535	tcf_block_owner_netif_keep_dst(block, q, ei->binder_type);
 536
 537	err = tcf_chain_head_change_cb_add(tcf_block_chain_zero(block),
 538					   ei, extack);
 539	if (err)
 540		goto err_chain_head_change_cb_add;
 541
 542	err = tcf_block_offload_bind(block, q, ei);
 543	if (err)
 544		goto err_block_offload_bind;
 545
 546	*p_block = block;
 547	return 0;
 548
 549err_block_offload_bind:
 550	tcf_chain_head_change_cb_del(tcf_block_chain_zero(block), ei);
 551err_chain_head_change_cb_add:
 552	tcf_block_owner_del(block, q, ei->binder_type);
 553err_block_owner_add:
 554	if (created) {
 555		if (tcf_block_shared(block))
 556			tcf_block_remove(block, net);
 557err_block_insert:
 558		kfree(tcf_block_chain_zero(block));
 559		kfree(block);
 560	} else {
 561		block->refcnt--;
 562	}
 563	return err;
 564}
 565EXPORT_SYMBOL(tcf_block_get_ext);
 566
 567static void tcf_chain_head_change_dflt(struct tcf_proto *tp_head, void *priv)
 568{
 569	struct tcf_proto __rcu **p_filter_chain = priv;
 570
 571	rcu_assign_pointer(*p_filter_chain, tp_head);
 572}
 573
 574int tcf_block_get(struct tcf_block **p_block,
 575		  struct tcf_proto __rcu **p_filter_chain, struct Qdisc *q,
 576		  struct netlink_ext_ack *extack)
 577{
 578	struct tcf_block_ext_info ei = {
 579		.chain_head_change = tcf_chain_head_change_dflt,
 580		.chain_head_change_priv = p_filter_chain,
 581	};
 582
 583	WARN_ON(!p_filter_chain);
 584	return tcf_block_get_ext(p_block, q, &ei, extack);
 585}
 586EXPORT_SYMBOL(tcf_block_get);
 587
 588/* XXX: Standalone actions are not allowed to jump to any chain, and bound
 589 * actions should be all removed after flushing.
 590 */
 591void tcf_block_put_ext(struct tcf_block *block, struct Qdisc *q,
 592		       struct tcf_block_ext_info *ei)
 593{
 594	struct tcf_chain *chain, *tmp;
 595
 596	if (!block)
 597		return;
 598	tcf_chain_head_change_cb_del(tcf_block_chain_zero(block), ei);
 599	tcf_block_owner_del(block, q, ei->binder_type);
 600
 601	if (--block->refcnt == 0) {
 602		if (tcf_block_shared(block))
 603			tcf_block_remove(block, block->net);
 604
 605		/* Hold a refcnt for all chains, so that they don't disappear
 606		 * while we are iterating.
 607		 */
 608		list_for_each_entry(chain, &block->chain_list, list)
 609			tcf_chain_hold(chain);
 610
 611		list_for_each_entry(chain, &block->chain_list, list)
 612			tcf_chain_flush(chain);
 613	}
 614
 615	tcf_block_offload_unbind(block, q, ei);
 616
 617	if (block->refcnt == 0) {
 618		/* At this point, all the chains should have refcnt >= 1. */
 619		list_for_each_entry_safe(chain, tmp, &block->chain_list, list)
 620			tcf_chain_put(chain);
 621
 622		/* Finally, put chain 0 and allow block to be freed. */
 623		tcf_chain_put(tcf_block_chain_zero(block));
 624	}
 625}
 626EXPORT_SYMBOL(tcf_block_put_ext);
 627
 628void tcf_block_put(struct tcf_block *block)
 629{
 630	struct tcf_block_ext_info ei = {0, };
 631
 632	if (!block)
 633		return;
 634	tcf_block_put_ext(block, block->q, &ei);
 635}
 636
 637EXPORT_SYMBOL(tcf_block_put);
 638
 639struct tcf_block_cb {
 640	struct list_head list;
 641	tc_setup_cb_t *cb;
 642	void *cb_ident;
 643	void *cb_priv;
 644	unsigned int refcnt;
 645};
 
 
 
 646
 647void *tcf_block_cb_priv(struct tcf_block_cb *block_cb)
 648{
 649	return block_cb->cb_priv;
 650}
 651EXPORT_SYMBOL(tcf_block_cb_priv);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 652
 653struct tcf_block_cb *tcf_block_cb_lookup(struct tcf_block *block,
 654					 tc_setup_cb_t *cb, void *cb_ident)
 655{	struct tcf_block_cb *block_cb;
 656
 657	list_for_each_entry(block_cb, &block->cb_list, list)
 658		if (block_cb->cb == cb && block_cb->cb_ident == cb_ident)
 659			return block_cb;
 660	return NULL;
 
 
 661}
 662EXPORT_SYMBOL(tcf_block_cb_lookup);
 663
 664void tcf_block_cb_incref(struct tcf_block_cb *block_cb)
 
 665{
 666	block_cb->refcnt++;
 667}
 668EXPORT_SYMBOL(tcf_block_cb_incref);
 669
 670unsigned int tcf_block_cb_decref(struct tcf_block_cb *block_cb)
 671{
 672	return --block_cb->refcnt;
 673}
 674EXPORT_SYMBOL(tcf_block_cb_decref);
 675
 676struct tcf_block_cb *__tcf_block_cb_register(struct tcf_block *block,
 677					     tc_setup_cb_t *cb, void *cb_ident,
 678					     void *cb_priv)
 679{
 680	struct tcf_block_cb *block_cb;
 
 
 
 
 681
 682	/* At this point, playback of previous block cb calls is not supported,
 683	 * so forbid to register to block which already has some offloaded
 684	 * filters present.
 685	 */
 686	if (tcf_block_offload_in_use(block))
 687		return ERR_PTR(-EOPNOTSUPP);
 688
 689	block_cb = kzalloc(sizeof(*block_cb), GFP_KERNEL);
 690	if (!block_cb)
 691		return ERR_PTR(-ENOMEM);
 692	block_cb->cb = cb;
 693	block_cb->cb_ident = cb_ident;
 694	block_cb->cb_priv = cb_priv;
 695	list_add(&block_cb->list, &block->cb_list);
 696	return block_cb;
 697}
 698EXPORT_SYMBOL(__tcf_block_cb_register);
 699
 700int tcf_block_cb_register(struct tcf_block *block,
 701			  tc_setup_cb_t *cb, void *cb_ident,
 702			  void *cb_priv)
 703{
 704	struct tcf_block_cb *block_cb;
 
 
 
 
 
 
 
 
 705
 706	block_cb = __tcf_block_cb_register(block, cb, cb_ident, cb_priv);
 707	return IS_ERR(block_cb) ? PTR_ERR(block_cb) : 0;
 708}
 709EXPORT_SYMBOL(tcf_block_cb_register);
 710
 711void __tcf_block_cb_unregister(struct tcf_block_cb *block_cb)
 
 712{
 713	list_del(&block_cb->list);
 714	kfree(block_cb);
 715}
 716EXPORT_SYMBOL(__tcf_block_cb_unregister);
 717
 718void tcf_block_cb_unregister(struct tcf_block *block,
 719			     tc_setup_cb_t *cb, void *cb_ident)
 720{
 721	struct tcf_block_cb *block_cb;
 722
 723	block_cb = tcf_block_cb_lookup(block, cb, cb_ident);
 724	if (!block_cb)
 725		return;
 726	__tcf_block_cb_unregister(block_cb);
 
 
 
 
 
 
 727}
 728EXPORT_SYMBOL(tcf_block_cb_unregister);
 729
 730static int tcf_block_cb_call(struct tcf_block *block, enum tc_setup_type type,
 731			     void *type_data, bool err_stop)
 732{
 733	struct tcf_block_cb *block_cb;
 734	int ok_count = 0;
 735	int err;
 736
 737	/* Make sure all netdevs sharing this block are offload-capable. */
 738	if (block->nooffloaddevcnt && err_stop)
 739		return -EOPNOTSUPP;
 
 
 
 
 
 
 
 
 
 740
 741	list_for_each_entry(block_cb, &block->cb_list, list) {
 742		err = block_cb->cb(type, type_data, block_cb->cb_priv);
 743		if (err) {
 744			if (err_stop)
 745				return err;
 746		} else {
 747			ok_count++;
 748		}
 749	}
 750	return ok_count;
 751}
 752
 753/* Main classifier routine: scans classifier chain attached
 754 * to this qdisc, (optionally) tests for protocol and asks
 755 * specific classifiers.
 756 */
 757int tcf_classify(struct sk_buff *skb, const struct tcf_proto *tp,
 758		 struct tcf_result *res, bool compat_mode)
 759{
 760	__be16 protocol = tc_skb_protocol(skb);
 761#ifdef CONFIG_NET_CLS_ACT
 762	const int max_reclassify_loop = 4;
 763	const struct tcf_proto *orig_tp = tp;
 764	const struct tcf_proto *first_tp;
 765	int limit = 0;
 766
 767reclassify:
 768#endif
 769	for (; tp; tp = rcu_dereference_bh(tp->next)) {
 
 770		int err;
 771
 772		if (tp->protocol != protocol &&
 773		    tp->protocol != htons(ETH_P_ALL))
 774			continue;
 775
 776		err = tp->classify(skb, tp, res);
 777#ifdef CONFIG_NET_CLS_ACT
 778		if (unlikely(err == TC_ACT_RECLASSIFY && !compat_mode)) {
 779			first_tp = orig_tp;
 780			goto reset;
 781		} else if (unlikely(TC_ACT_EXT_CMP(err, TC_ACT_GOTO_CHAIN))) {
 782			first_tp = res->goto_tp;
 
 
 
 
 
 
 
 
 
 
 
 
 783			goto reset;
 784		}
 785#endif
 786		if (err >= 0)
 787			return err;
 788	}
 789
 790	return TC_ACT_UNSPEC; /* signal: continue lookup */
 791#ifdef CONFIG_NET_CLS_ACT
 792reset:
 793	if (unlikely(limit++ >= max_reclassify_loop)) {
 794		net_notice_ratelimited("%u: reclassify loop, rule prio %u, protocol %02x\n",
 795				       tp->chain->block->index,
 796				       tp->prio & 0xffff,
 797				       ntohs(tp->protocol));
 798		return TC_ACT_SHOT;
 799	}
 800
 801	tp = first_tp;
 802	protocol = tc_skb_protocol(skb);
 803	goto reclassify;
 804#endif
 805}
 806EXPORT_SYMBOL(tcf_classify);
 807
 808struct tcf_chain_info {
 809	struct tcf_proto __rcu **pprev;
 810	struct tcf_proto __rcu *next;
 811};
 812
 813static struct tcf_proto *tcf_chain_tp_prev(struct tcf_chain_info *chain_info)
 
 814{
 815	return rtnl_dereference(*chain_info->pprev);
 816}
 817
 818static void tcf_chain_tp_insert(struct tcf_chain *chain,
 819				struct tcf_chain_info *chain_info,
 820				struct tcf_proto *tp)
 821{
 
 
 
 822	if (*chain_info->pprev == chain->filter_chain)
 823		tcf_chain_head_change(chain, tp);
 824	RCU_INIT_POINTER(tp->next, tcf_chain_tp_prev(chain_info));
 
 825	rcu_assign_pointer(*chain_info->pprev, tp);
 826	tcf_chain_hold(chain);
 
 827}
 828
 829static void tcf_chain_tp_remove(struct tcf_chain *chain,
 830				struct tcf_chain_info *chain_info,
 831				struct tcf_proto *tp)
 832{
 833	struct tcf_proto *next = rtnl_dereference(chain_info->next);
 834
 
 835	if (tp == chain->filter_chain)
 836		tcf_chain_head_change(chain, next);
 837	RCU_INIT_POINTER(*chain_info->pprev, next);
 838	tcf_chain_put(chain);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 839}
 840
 841static struct tcf_proto *tcf_chain_tp_find(struct tcf_chain *chain,
 842					   struct tcf_chain_info *chain_info,
 843					   u32 protocol, u32 prio,
 844					   bool prio_allocate)
 845{
 846	struct tcf_proto **pprev;
 847	struct tcf_proto *tp;
 848
 849	/* Check the chain for existence of proto-tcf with this priority */
 850	for (pprev = &chain->filter_chain;
 851	     (tp = rtnl_dereference(*pprev)); pprev = &tp->next) {
 
 852		if (tp->prio >= prio) {
 853			if (tp->prio == prio) {
 854				if (prio_allocate ||
 855				    (tp->protocol != protocol && protocol))
 856					return ERR_PTR(-EINVAL);
 857			} else {
 858				tp = NULL;
 859			}
 860			break;
 861		}
 862	}
 863	chain_info->pprev = pprev;
 864	chain_info->next = tp ? tp->next : NULL;
 
 
 
 
 
 865	return tp;
 866}
 867
 868static int tcf_fill_node(struct net *net, struct sk_buff *skb,
 869			 struct tcf_proto *tp, struct tcf_block *block,
 870			 struct Qdisc *q, u32 parent, void *fh,
 871			 u32 portid, u32 seq, u16 flags, int event)
 
 872{
 873	struct tcmsg *tcm;
 874	struct nlmsghdr  *nlh;
 875	unsigned char *b = skb_tail_pointer(skb);
 876
 877	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*tcm), flags);
 878	if (!nlh)
 879		goto out_nlmsg_trim;
 880	tcm = nlmsg_data(nlh);
 881	tcm->tcm_family = AF_UNSPEC;
 882	tcm->tcm__pad1 = 0;
 883	tcm->tcm__pad2 = 0;
 884	if (q) {
 885		tcm->tcm_ifindex = qdisc_dev(q)->ifindex;
 886		tcm->tcm_parent = parent;
 887	} else {
 888		tcm->tcm_ifindex = TCM_IFINDEX_MAGIC_BLOCK;
 889		tcm->tcm_block_index = block->index;
 890	}
 891	tcm->tcm_info = TC_H_MAKE(tp->prio, tp->protocol);
 892	if (nla_put_string(skb, TCA_KIND, tp->ops->kind))
 893		goto nla_put_failure;
 894	if (nla_put_u32(skb, TCA_CHAIN, tp->chain->index))
 895		goto nla_put_failure;
 896	if (!fh) {
 897		tcm->tcm_handle = 0;
 898	} else {
 899		if (tp->ops->dump && tp->ops->dump(net, tp, fh, skb, tcm) < 0)
 
 900			goto nla_put_failure;
 901	}
 902	nlh->nlmsg_len = skb_tail_pointer(skb) - b;
 903	return skb->len;
 904
 905out_nlmsg_trim:
 906nla_put_failure:
 907	nlmsg_trim(skb, b);
 908	return -1;
 909}
 910
 911static int tfilter_notify(struct net *net, struct sk_buff *oskb,
 912			  struct nlmsghdr *n, struct tcf_proto *tp,
 913			  struct tcf_block *block, struct Qdisc *q,
 914			  u32 parent, void *fh, int event, bool unicast)
 
 915{
 916	struct sk_buff *skb;
 917	u32 portid = oskb ? NETLINK_CB(oskb).portid : 0;
 
 918
 919	skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
 920	if (!skb)
 921		return -ENOBUFS;
 922
 923	if (tcf_fill_node(net, skb, tp, block, q, parent, fh, portid,
 924			  n->nlmsg_seq, n->nlmsg_flags, event) <= 0) {
 
 925		kfree_skb(skb);
 926		return -EINVAL;
 927	}
 928
 929	if (unicast)
 930		return netlink_unicast(net->rtnl, skb, portid, MSG_DONTWAIT);
 
 
 
 931
 932	return rtnetlink_send(skb, net, portid, RTNLGRP_TC,
 933			      n->nlmsg_flags & NLM_F_ECHO);
 
 934}
 935
 936static int tfilter_del_notify(struct net *net, struct sk_buff *oskb,
 937			      struct nlmsghdr *n, struct tcf_proto *tp,
 938			      struct tcf_block *block, struct Qdisc *q,
 939			      u32 parent, void *fh, bool unicast, bool *last,
 940			      struct netlink_ext_ack *extack)
 941{
 942	struct sk_buff *skb;
 943	u32 portid = oskb ? NETLINK_CB(oskb).portid : 0;
 944	int err;
 945
 946	skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
 947	if (!skb)
 948		return -ENOBUFS;
 949
 950	if (tcf_fill_node(net, skb, tp, block, q, parent, fh, portid,
 951			  n->nlmsg_seq, n->nlmsg_flags, RTM_DELTFILTER) <= 0) {
 
 952		NL_SET_ERR_MSG(extack, "Failed to build del event notification");
 953		kfree_skb(skb);
 954		return -EINVAL;
 955	}
 956
 957	err = tp->ops->delete(tp, fh, last, extack);
 958	if (err) {
 959		kfree_skb(skb);
 960		return err;
 961	}
 962
 963	if (unicast)
 964		return netlink_unicast(net->rtnl, skb, portid, MSG_DONTWAIT);
 965
 966	err = rtnetlink_send(skb, net, portid, RTNLGRP_TC,
 967			     n->nlmsg_flags & NLM_F_ECHO);
 968	if (err < 0)
 969		NL_SET_ERR_MSG(extack, "Failed to send filter delete notification");
 
 
 
 970	return err;
 971}
 972
 973static void tfilter_notify_chain(struct net *net, struct sk_buff *oskb,
 974				 struct tcf_block *block, struct Qdisc *q,
 975				 u32 parent, struct nlmsghdr *n,
 976				 struct tcf_chain *chain, int event)
 
 977{
 978	struct tcf_proto *tp;
 979
 980	for (tp = rtnl_dereference(chain->filter_chain);
 981	     tp; tp = rtnl_dereference(tp->next))
 982		tfilter_notify(net, oskb, n, tp, block,
 983			       q, parent, 0, event, false);
 984}
 985
 986/* Add/change/delete/get a filter node */
 
 
 
 
 987
 988static int tc_ctl_tfilter(struct sk_buff *skb, struct nlmsghdr *n,
 989			  struct netlink_ext_ack *extack)
 990{
 991	struct net *net = sock_net(skb->sk);
 992	struct nlattr *tca[TCA_MAX + 1];
 
 993	struct tcmsg *t;
 994	u32 protocol;
 995	u32 prio;
 996	bool prio_allocate;
 997	u32 parent;
 998	u32 chain_index;
 999	struct Qdisc *q = NULL;
1000	struct tcf_chain_info chain_info;
1001	struct tcf_chain *chain = NULL;
1002	struct tcf_block *block;
1003	struct tcf_proto *tp;
1004	unsigned long cl;
1005	void *fh;
1006	int err;
1007	int tp_created;
 
1008
1009	if ((n->nlmsg_type != RTM_GETTFILTER) &&
1010	    !netlink_ns_capable(skb, net->user_ns, CAP_NET_ADMIN))
1011		return -EPERM;
1012
1013replay:
1014	tp_created = 0;
1015
1016	err = nlmsg_parse(n, sizeof(*t), tca, TCA_MAX, NULL, extack);
 
1017	if (err < 0)
1018		return err;
1019
1020	t = nlmsg_data(n);
1021	protocol = TC_H_MIN(t->tcm_info);
1022	prio = TC_H_MAJ(t->tcm_info);
1023	prio_allocate = false;
1024	parent = t->tcm_parent;
 
1025	cl = 0;
 
1026
1027	if (prio == 0) {
1028		switch (n->nlmsg_type) {
1029		case RTM_DELTFILTER:
1030			if (protocol || t->tcm_handle || tca[TCA_KIND]) {
1031				NL_SET_ERR_MSG(extack, "Cannot flush filters with protocol, handle or kind set");
1032				return -ENOENT;
1033			}
1034			break;
1035		case RTM_NEWTFILTER:
1036			/* If no priority is provided by the user,
1037			 * we allocate one.
1038			 */
1039			if (n->nlmsg_flags & NLM_F_CREATE) {
1040				prio = TC_H_MAKE(0x80000000U, 0U);
1041				prio_allocate = true;
1042				break;
1043			}
1044			/* fall-through */
1045		default:
1046			NL_SET_ERR_MSG(extack, "Invalid filter command with priority of zero");
1047			return -ENOENT;
1048		}
1049	}
1050
1051	/* Find head of filter chain. */
1052
1053	if (t->tcm_ifindex == TCM_IFINDEX_MAGIC_BLOCK) {
1054		block = tcf_block_lookup(net, t->tcm_block_index);
1055		if (!block) {
1056			NL_SET_ERR_MSG(extack, "Block of given index was not found");
1057			err = -EINVAL;
1058			goto errout;
1059		}
1060	} else {
1061		const struct Qdisc_class_ops *cops;
1062		struct net_device *dev;
1063
1064		/* Find link */
1065		dev = __dev_get_by_index(net, t->tcm_ifindex);
1066		if (!dev)
1067			return -ENODEV;
 
1068
1069		/* Find qdisc */
1070		if (!parent) {
1071			q = dev->qdisc;
1072			parent = q->handle;
1073		} else {
1074			q = qdisc_lookup(dev, TC_H_MAJ(t->tcm_parent));
1075			if (!q) {
1076				NL_SET_ERR_MSG(extack, "Parent Qdisc doesn't exists");
1077				return -EINVAL;
1078			}
1079		}
1080
1081		/* Is it classful? */
1082		cops = q->ops->cl_ops;
1083		if (!cops) {
1084			NL_SET_ERR_MSG(extack, "Qdisc not classful");
1085			return -EINVAL;
1086		}
1087
1088		if (!cops->tcf_block) {
1089			NL_SET_ERR_MSG(extack, "Class doesn't support blocks");
1090			return -EOPNOTSUPP;
1091		}
1092
1093		/* Do we search for filter, attached to class? */
1094		if (TC_H_MIN(parent)) {
1095			cl = cops->find(q, parent);
1096			if (cl == 0) {
1097				NL_SET_ERR_MSG(extack, "Specified class doesn't exist");
1098				return -ENOENT;
1099			}
1100		}
1101
1102		/* And the last stroke */
1103		block = cops->tcf_block(q, cl, extack);
1104		if (!block) {
1105			err = -EINVAL;
1106			goto errout;
1107		}
1108		if (tcf_block_shared(block)) {
1109			NL_SET_ERR_MSG(extack, "This filter block is shared. Please use the block index to manipulate the filters");
1110			err = -EOPNOTSUPP;
1111			goto errout;
1112		}
1113	}
1114
1115	chain_index = tca[TCA_CHAIN] ? nla_get_u32(tca[TCA_CHAIN]) : 0;
1116	if (chain_index > TC_ACT_EXT_VAL_MASK) {
1117		NL_SET_ERR_MSG(extack, "Specified chain index exceeds upper limit");
1118		err = -EINVAL;
1119		goto errout;
1120	}
1121	chain = tcf_chain_get(block, chain_index,
1122			      n->nlmsg_type == RTM_NEWTFILTER);
1123	if (!chain) {
1124		NL_SET_ERR_MSG(extack, "Cannot find specified filter chain");
1125		err = n->nlmsg_type == RTM_NEWTFILTER ? -ENOMEM : -EINVAL;
1126		goto errout;
1127	}
1128
1129	if (n->nlmsg_type == RTM_DELTFILTER && prio == 0) {
1130		tfilter_notify_chain(net, skb, block, q, parent, n,
1131				     chain, RTM_DELTFILTER);
1132		tcf_chain_flush(chain);
1133		err = 0;
1134		goto errout;
1135	}
1136
 
1137	tp = tcf_chain_tp_find(chain, &chain_info, protocol,
1138			       prio, prio_allocate);
1139	if (IS_ERR(tp)) {
1140		NL_SET_ERR_MSG(extack, "Filter with specified priority/protocol not found");
1141		err = PTR_ERR(tp);
1142		goto errout;
1143	}
1144
1145	if (tp == NULL) {
 
 
 
 
 
 
 
1146		/* Proto-tcf does not exist, create new one */
1147
1148		if (tca[TCA_KIND] == NULL || !protocol) {
1149			NL_SET_ERR_MSG(extack, "Filter kind and protocol must be specified");
1150			err = -EINVAL;
1151			goto errout;
1152		}
1153
1154		if (n->nlmsg_type != RTM_NEWTFILTER ||
1155		    !(n->nlmsg_flags & NLM_F_CREATE)) {
1156			NL_SET_ERR_MSG(extack, "Need both RTM_NEWTFILTER and NLM_F_CREATE to create a new filter");
1157			err = -ENOENT;
1158			goto errout;
1159		}
1160
1161		if (prio_allocate)
1162			prio = tcf_auto_prio(tcf_chain_tp_prev(&chain_info));
 
1163
1164		tp = tcf_proto_create(nla_data(tca[TCA_KIND]),
1165				      protocol, prio, chain, extack);
 
 
 
 
 
 
 
 
 
 
1166		if (IS_ERR(tp)) {
1167			err = PTR_ERR(tp);
1168			goto errout;
1169		}
1170		tp_created = 1;
1171	} else if (tca[TCA_KIND] && nla_strcmp(tca[TCA_KIND], tp->ops->kind)) {
 
 
 
1172		NL_SET_ERR_MSG(extack, "Specified filter kind does not match existing one");
1173		err = -EINVAL;
1174		goto errout;
1175	}
1176
1177	fh = tp->ops->get(tp, t->tcm_handle);
1178
1179	if (!fh) {
1180		if (n->nlmsg_type == RTM_DELTFILTER && t->tcm_handle == 0) {
1181			tcf_chain_tp_remove(chain, &chain_info, tp);
1182			tfilter_notify(net, skb, n, tp, block, q, parent, fh,
1183				       RTM_DELTFILTER, false);
1184			tcf_proto_destroy(tp, extack);
1185			err = 0;
1186			goto errout;
1187		}
 
 
 
 
 
 
 
 
 
 
 
 
1188
1189		if (n->nlmsg_type != RTM_NEWTFILTER ||
1190		    !(n->nlmsg_flags & NLM_F_CREATE)) {
1191			NL_SET_ERR_MSG(extack, "Need both RTM_NEWTFILTER and NLM_F_CREATE to create a new filter");
1192			err = -ENOENT;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1193			goto errout;
1194		}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1195	} else {
1196		bool last;
1197
1198		switch (n->nlmsg_type) {
1199		case RTM_NEWTFILTER:
1200			if (n->nlmsg_flags & NLM_F_EXCL) {
1201				if (tp_created)
1202					tcf_proto_destroy(tp, NULL);
1203				NL_SET_ERR_MSG(extack, "Filter already exists");
1204				err = -EEXIST;
1205				goto errout;
1206			}
1207			break;
1208		case RTM_DELTFILTER:
1209			err = tfilter_del_notify(net, skb, n, tp, block,
1210						 q, parent, fh, false, &last,
1211						 extack);
1212			if (err)
1213				goto errout;
1214			if (last) {
1215				tcf_chain_tp_remove(chain, &chain_info, tp);
1216				tcf_proto_destroy(tp, extack);
1217			}
1218			goto errout;
1219		case RTM_GETTFILTER:
1220			err = tfilter_notify(net, skb, n, tp, block, q, parent,
1221					     fh, RTM_NEWTFILTER, true);
1222			if (err < 0)
1223				NL_SET_ERR_MSG(extack, "Failed to send filter notify message");
1224			goto errout;
1225		default:
1226			NL_SET_ERR_MSG(extack, "Invalid netlink message type");
1227			err = -EINVAL;
1228			goto errout;
1229		}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1230	}
1231
1232	err = tp->ops->change(net, skb, tp, cl, t->tcm_handle, tca, &fh,
1233			      n->nlmsg_flags & NLM_F_CREATE ? TCA_ACT_NOREPLACE : TCA_ACT_REPLACE,
1234			      extack);
1235	if (err == 0) {
1236		if (tp_created)
1237			tcf_chain_tp_insert(chain, &chain_info, tp);
1238		tfilter_notify(net, skb, n, tp, block, q, parent, fh,
1239			       RTM_NEWTFILTER, false);
1240	} else {
1241		if (tp_created)
1242			tcf_proto_destroy(tp, NULL);
 
 
1243	}
1244
 
1245errout:
1246	if (chain)
 
 
1247		tcf_chain_put(chain);
1248	if (err == -EAGAIN)
1249		/* Replay the request. */
1250		goto replay;
 
 
 
1251	return err;
1252}
1253
1254struct tcf_dump_args {
1255	struct tcf_walker w;
1256	struct sk_buff *skb;
1257	struct netlink_callback *cb;
1258	struct tcf_block *block;
1259	struct Qdisc *q;
1260	u32 parent;
1261};
1262
1263static int tcf_node_dump(struct tcf_proto *tp, void *n, struct tcf_walker *arg)
1264{
1265	struct tcf_dump_args *a = (void *)arg;
1266	struct net *net = sock_net(a->skb->sk);
1267
1268	return tcf_fill_node(net, a->skb, tp, a->block, a->q, a->parent,
1269			     n, NETLINK_CB(a->cb->skb).portid,
1270			     a->cb->nlh->nlmsg_seq, NLM_F_MULTI,
1271			     RTM_NEWTFILTER);
1272}
1273
1274static bool tcf_chain_dump(struct tcf_chain *chain, struct Qdisc *q, u32 parent,
1275			   struct sk_buff *skb, struct netlink_callback *cb,
1276			   long index_start, long *p_index)
1277{
1278	struct net *net = sock_net(skb->sk);
1279	struct tcf_block *block = chain->block;
1280	struct tcmsg *tcm = nlmsg_data(cb->nlh);
 
1281	struct tcf_dump_args arg;
1282	struct tcf_proto *tp;
1283
1284	for (tp = rtnl_dereference(chain->filter_chain);
1285	     tp; tp = rtnl_dereference(tp->next), (*p_index)++) {
 
 
 
 
1286		if (*p_index < index_start)
1287			continue;
1288		if (TC_H_MAJ(tcm->tcm_info) &&
1289		    TC_H_MAJ(tcm->tcm_info) != tp->prio)
1290			continue;
1291		if (TC_H_MIN(tcm->tcm_info) &&
1292		    TC_H_MIN(tcm->tcm_info) != tp->protocol)
1293			continue;
1294		if (*p_index > index_start)
1295			memset(&cb->args[1], 0,
1296			       sizeof(cb->args) - sizeof(cb->args[0]));
1297		if (cb->args[1] == 0) {
1298			if (tcf_fill_node(net, skb, tp, block, q, parent, 0,
1299					  NETLINK_CB(cb->skb).portid,
1300					  cb->nlh->nlmsg_seq, NLM_F_MULTI,
1301					  RTM_NEWTFILTER) <= 0)
1302				return false;
1303
1304			cb->args[1] = 1;
1305		}
1306		if (!tp->ops->walk)
1307			continue;
1308		arg.w.fn = tcf_node_dump;
1309		arg.skb = skb;
1310		arg.cb = cb;
1311		arg.block = block;
1312		arg.q = q;
1313		arg.parent = parent;
1314		arg.w.stop = 0;
1315		arg.w.skip = cb->args[1] - 1;
1316		arg.w.count = 0;
1317		tp->ops->walk(tp, &arg.w);
 
 
1318		cb->args[1] = arg.w.count + 1;
1319		if (arg.w.stop)
1320			return false;
1321	}
1322	return true;
 
 
 
 
1323}
1324
1325/* called with RTNL */
1326static int tc_dump_tfilter(struct sk_buff *skb, struct netlink_callback *cb)
1327{
 
1328	struct net *net = sock_net(skb->sk);
1329	struct nlattr *tca[TCA_MAX + 1];
1330	struct Qdisc *q = NULL;
1331	struct tcf_block *block;
1332	struct tcf_chain *chain;
1333	struct tcmsg *tcm = nlmsg_data(cb->nlh);
1334	long index_start;
1335	long index;
1336	u32 parent;
1337	int err;
1338
1339	if (nlmsg_len(cb->nlh) < sizeof(*tcm))
1340		return skb->len;
1341
1342	err = nlmsg_parse(cb->nlh, sizeof(*tcm), tca, TCA_MAX, NULL, NULL);
 
1343	if (err)
1344		return err;
1345
1346	if (tcm->tcm_ifindex == TCM_IFINDEX_MAGIC_BLOCK) {
1347		block = tcf_block_lookup(net, tcm->tcm_block_index);
1348		if (!block)
1349			goto out;
1350		/* If we work with block index, q is NULL and parent value
1351		 * will never be used in the following code. The check
1352		 * in tcf_fill_node prevents it. However, compiler does not
1353		 * see that far, so set parent to zero to silence the warning
1354		 * about parent being uninitialized.
1355		 */
1356		parent = 0;
1357	} else {
1358		const struct Qdisc_class_ops *cops;
1359		struct net_device *dev;
1360		unsigned long cl = 0;
1361
1362		dev = __dev_get_by_index(net, tcm->tcm_ifindex);
1363		if (!dev)
1364			return skb->len;
1365
1366		parent = tcm->tcm_parent;
1367		if (!parent) {
1368			q = dev->qdisc;
1369			parent = q->handle;
1370		} else {
1371			q = qdisc_lookup(dev, TC_H_MAJ(tcm->tcm_parent));
1372		}
1373		if (!q)
1374			goto out;
1375		cops = q->ops->cl_ops;
1376		if (!cops)
1377			goto out;
1378		if (!cops->tcf_block)
1379			goto out;
1380		if (TC_H_MIN(tcm->tcm_parent)) {
1381			cl = cops->find(q, tcm->tcm_parent);
1382			if (cl == 0)
1383				goto out;
1384		}
1385		block = cops->tcf_block(q, cl, NULL);
1386		if (!block)
1387			goto out;
1388		if (tcf_block_shared(block))
1389			q = NULL;
1390	}
1391
1392	index_start = cb->args[0];
1393	index = 0;
1394
1395	list_for_each_entry(chain, &block->chain_list, list) {
 
 
 
 
1396		if (tca[TCA_CHAIN] &&
1397		    nla_get_u32(tca[TCA_CHAIN]) != chain->index)
1398			continue;
1399		if (!tcf_chain_dump(chain, q, parent, skb, cb,
1400				    index_start, &index)) {
 
1401			err = -EMSGSIZE;
1402			break;
1403		}
1404	}
1405
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1406	cb->args[0] = index;
1407
1408out:
1409	/* If we did no progress, the error (EMSGSIZE) is real */
1410	if (skb->len == 0 && err)
1411		return err;
1412	return skb->len;
1413}
1414
1415void tcf_exts_destroy(struct tcf_exts *exts)
1416{
1417#ifdef CONFIG_NET_CLS_ACT
1418	LIST_HEAD(actions);
1419
1420	ASSERT_RTNL();
1421	tcf_exts_to_list(exts, &actions);
1422	tcf_action_destroy(&actions, TCA_ACT_UNBIND);
1423	kfree(exts->actions);
1424	exts->nr_actions = 0;
1425#endif
1426}
1427EXPORT_SYMBOL(tcf_exts_destroy);
1428
1429int tcf_exts_validate(struct net *net, struct tcf_proto *tp, struct nlattr **tb,
1430		      struct nlattr *rate_tlv, struct tcf_exts *exts, bool ovr,
1431		      struct netlink_ext_ack *extack)
1432{
1433#ifdef CONFIG_NET_CLS_ACT
1434	{
1435		struct tc_action *act;
1436		size_t attr_size = 0;
1437
1438		if (exts->police && tb[exts->police]) {
1439			act = tcf_action_init_1(net, tp, tb[exts->police],
1440						rate_tlv, "police", ovr,
1441						TCA_ACT_BIND, extack);
 
1442			if (IS_ERR(act))
1443				return PTR_ERR(act);
1444
1445			act->type = exts->type = TCA_OLD_COMPAT;
1446			exts->actions[0] = act;
1447			exts->nr_actions = 1;
1448		} else if (exts->action && tb[exts->action]) {
1449			LIST_HEAD(actions);
1450			int err, i = 0;
1451
1452			err = tcf_action_init(net, tp, tb[exts->action],
1453					      rate_tlv, NULL, ovr, TCA_ACT_BIND,
1454					      &actions, &attr_size, extack);
1455			if (err)
 
1456				return err;
1457			list_for_each_entry(act, &actions, list)
1458				exts->actions[i++] = act;
1459			exts->nr_actions = i;
1460		}
1461		exts->net = net;
1462	}
1463#else
1464	if ((exts->action && tb[exts->action]) ||
1465	    (exts->police && tb[exts->police])) {
1466		NL_SET_ERR_MSG(extack, "Classifier actions are not supported per compile options (CONFIG_NET_CLS_ACT)");
1467		return -EOPNOTSUPP;
1468	}
1469#endif
1470
1471	return 0;
1472}
1473EXPORT_SYMBOL(tcf_exts_validate);
1474
1475void tcf_exts_change(struct tcf_exts *dst, struct tcf_exts *src)
1476{
1477#ifdef CONFIG_NET_CLS_ACT
1478	struct tcf_exts old = *dst;
1479
1480	*dst = *src;
1481	tcf_exts_destroy(&old);
1482#endif
1483}
1484EXPORT_SYMBOL(tcf_exts_change);
1485
1486#ifdef CONFIG_NET_CLS_ACT
1487static struct tc_action *tcf_exts_first_act(struct tcf_exts *exts)
1488{
1489	if (exts->nr_actions == 0)
1490		return NULL;
1491	else
1492		return exts->actions[0];
1493}
1494#endif
1495
1496int tcf_exts_dump(struct sk_buff *skb, struct tcf_exts *exts)
1497{
1498#ifdef CONFIG_NET_CLS_ACT
1499	struct nlattr *nest;
1500
1501	if (exts->action && tcf_exts_has_actions(exts)) {
1502		/*
1503		 * again for backward compatible mode - we want
1504		 * to work with both old and new modes of entering
1505		 * tc data even if iproute2  was newer - jhs
1506		 */
1507		if (exts->type != TCA_OLD_COMPAT) {
1508			LIST_HEAD(actions);
1509
1510			nest = nla_nest_start(skb, exts->action);
1511			if (nest == NULL)
1512				goto nla_put_failure;
1513
1514			tcf_exts_to_list(exts, &actions);
1515			if (tcf_action_dump(skb, &actions, 0, 0) < 0)
1516				goto nla_put_failure;
1517			nla_nest_end(skb, nest);
1518		} else if (exts->police) {
1519			struct tc_action *act = tcf_exts_first_act(exts);
1520			nest = nla_nest_start(skb, exts->police);
1521			if (nest == NULL || !act)
1522				goto nla_put_failure;
1523			if (tcf_action_dump_old(skb, act, 0, 0) < 0)
1524				goto nla_put_failure;
1525			nla_nest_end(skb, nest);
1526		}
1527	}
1528	return 0;
1529
1530nla_put_failure:
1531	nla_nest_cancel(skb, nest);
1532	return -1;
1533#else
1534	return 0;
1535#endif
1536}
1537EXPORT_SYMBOL(tcf_exts_dump);
1538
1539
1540int tcf_exts_dump_stats(struct sk_buff *skb, struct tcf_exts *exts)
1541{
1542#ifdef CONFIG_NET_CLS_ACT
1543	struct tc_action *a = tcf_exts_first_act(exts);
1544	if (a != NULL && tcf_action_copy_stats(skb, a, 1) < 0)
1545		return -1;
1546#endif
1547	return 0;
1548}
1549EXPORT_SYMBOL(tcf_exts_dump_stats);
1550
1551static int tc_exts_setup_cb_egdev_call(struct tcf_exts *exts,
1552				       enum tc_setup_type type,
1553				       void *type_data, bool err_stop)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1554{
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1555	int ok_count = 0;
1556#ifdef CONFIG_NET_CLS_ACT
1557	const struct tc_action *a;
1558	struct net_device *dev;
1559	int i, ret;
1560
1561	if (!tcf_exts_has_actions(exts))
1562		return 0;
1563
1564	for (i = 0; i < exts->nr_actions; i++) {
1565		a = exts->actions[i];
1566		if (!a->ops->get_dev)
1567			continue;
1568		dev = a->ops->get_dev(a);
1569		if (!dev)
1570			continue;
1571		ret = tc_setup_cb_egdev_call(dev, type, type_data, err_stop);
1572		if (ret < 0)
1573			return ret;
1574		ok_count += ret;
1575	}
1576#endif
1577	return ok_count;
1578}
1579
1580int tc_setup_cb_call(struct tcf_block *block, struct tcf_exts *exts,
1581		     enum tc_setup_type type, void *type_data, bool err_stop)
1582{
 
1583	int ok_count;
1584	int ret;
1585
1586	ret = tcf_block_cb_call(block, type, type_data, err_stop);
1587	if (ret < 0)
1588		return ret;
1589	ok_count = ret;
1590
1591	if (!exts || ok_count)
1592		return ok_count;
1593	ret = tc_exts_setup_cb_egdev_call(exts, type, type_data, err_stop);
1594	if (ret < 0)
1595		return ret;
1596	ok_count += ret;
 
 
 
 
1597
 
 
 
1598	return ok_count;
1599}
1600EXPORT_SYMBOL(tc_setup_cb_call);
1601
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1602static __net_init int tcf_net_init(struct net *net)
1603{
1604	struct tcf_net *tn = net_generic(net, tcf_net_id);
1605
 
1606	idr_init(&tn->idr);
1607	return 0;
1608}
1609
1610static void __net_exit tcf_net_exit(struct net *net)
1611{
1612	struct tcf_net *tn = net_generic(net, tcf_net_id);
1613
1614	idr_destroy(&tn->idr);
1615}
1616
1617static struct pernet_operations tcf_net_ops = {
1618	.init = tcf_net_init,
1619	.exit = tcf_net_exit,
1620	.id   = &tcf_net_id,
1621	.size = sizeof(struct tcf_net),
1622};
1623
 
 
 
 
 
1624static int __init tc_filter_init(void)
1625{
1626	int err;
1627
1628	tc_filter_wq = alloc_ordered_workqueue("tc_filter_workqueue", 0);
1629	if (!tc_filter_wq)
1630		return -ENOMEM;
1631
1632	err = register_pernet_subsys(&tcf_net_ops);
1633	if (err)
1634		goto err_register_pernet_subsys;
1635
1636	rtnl_register(PF_UNSPEC, RTM_NEWTFILTER, tc_ctl_tfilter, NULL, 0);
1637	rtnl_register(PF_UNSPEC, RTM_DELTFILTER, tc_ctl_tfilter, NULL, 0);
1638	rtnl_register(PF_UNSPEC, RTM_GETTFILTER, tc_ctl_tfilter,
1639		      tc_dump_tfilter, 0);
 
 
 
 
 
 
 
 
1640
1641	return 0;
1642
1643err_register_pernet_subsys:
1644	destroy_workqueue(tc_filter_wq);
1645	return err;
1646}
1647
1648subsys_initcall(tc_filter_init);