cls_api.c 28.4 KB
Newer Older
L
Linus Torvalds 已提交
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21
/*
 * net/sched/cls_api.c	Packet classifier API.
 *
 *		This program is free software; you can redistribute it and/or
 *		modify it under the terms of the GNU General Public License
 *		as published by the Free Software Foundation; either version
 *		2 of the License, or (at your option) any later version.
 *
 * Authors:	Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
 *
 * Changes:
 *
 * Eduardo J. Blanco <ejbs@netlabs.com.uy> :990222: kmod support
 *
 */

#include <linux/module.h>
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/string.h>
#include <linux/errno.h>
22
#include <linux/err.h>
L
Linus Torvalds 已提交
23 24 25
#include <linux/skbuff.h>
#include <linux/init.h>
#include <linux/kmod.h>
26
#include <linux/err.h>
27
#include <linux/slab.h>
28 29
#include <net/net_namespace.h>
#include <net/sock.h>
30
#include <net/netlink.h>
L
Linus Torvalds 已提交
31 32 33 34
#include <net/pkt_sched.h>
#include <net/pkt_cls.h>

/* The list of all installed classifier types */
35
static LIST_HEAD(tcf_proto_base);
L
Linus Torvalds 已提交
36 37 38 39 40 41

/* Protects list of registered TC modules. It is pure SMP lock. */
static DEFINE_RWLOCK(cls_mod_lock);

/* Find classifier type by string name */

42
static const struct tcf_proto_ops *tcf_proto_lookup_ops(const char *kind)
L
Linus Torvalds 已提交
43
{
44
	const struct tcf_proto_ops *t, *res = NULL;
L
Linus Torvalds 已提交
45 46 47

	if (kind) {
		read_lock(&cls_mod_lock);
48
		list_for_each_entry(t, &tcf_proto_base, head) {
49
			if (strcmp(kind, t->kind) == 0) {
50 51
				if (try_module_get(t->owner))
					res = t;
L
Linus Torvalds 已提交
52 53 54 55 56
				break;
			}
		}
		read_unlock(&cls_mod_lock);
	}
57
	return res;
L
Linus Torvalds 已提交
58 59 60 61 62 63
}

/* Register(unregister) new classifier type */

int register_tcf_proto_ops(struct tcf_proto_ops *ops)
{
64
	struct tcf_proto_ops *t;
L
Linus Torvalds 已提交
65 66 67
	int rc = -EEXIST;

	write_lock(&cls_mod_lock);
68
	list_for_each_entry(t, &tcf_proto_base, head)
L
Linus Torvalds 已提交
69 70 71
		if (!strcmp(ops->kind, t->kind))
			goto out;

72
	list_add_tail(&ops->head, &tcf_proto_base);
L
Linus Torvalds 已提交
73 74 75 76 77
	rc = 0;
out:
	write_unlock(&cls_mod_lock);
	return rc;
}
78
EXPORT_SYMBOL(register_tcf_proto_ops);
L
Linus Torvalds 已提交
79 80 81

int unregister_tcf_proto_ops(struct tcf_proto_ops *ops)
{
82
	struct tcf_proto_ops *t;
L
Linus Torvalds 已提交
83 84
	int rc = -ENOENT;

85 86 87 88 89
	/* Wait for outstanding call_rcu()s, if any, from a
	 * tcf_proto_ops's destroy() handler.
	 */
	rcu_barrier();

L
Linus Torvalds 已提交
90
	write_lock(&cls_mod_lock);
91 92 93 94
	list_for_each_entry(t, &tcf_proto_base, head) {
		if (t == ops) {
			list_del(&t->head);
			rc = 0;
L
Linus Torvalds 已提交
95
			break;
96 97
		}
	}
L
Linus Torvalds 已提交
98 99 100
	write_unlock(&cls_mod_lock);
	return rc;
}
101
EXPORT_SYMBOL(unregister_tcf_proto_ops);
L
Linus Torvalds 已提交
102 103 104

/* Select new prio value from the range, managed by kernel. */

105
static inline u32 tcf_auto_prio(struct tcf_proto *tp)
L
Linus Torvalds 已提交
106
{
107
	u32 first = TC_H_MAKE(0xC0000000U, 0U);
L
Linus Torvalds 已提交
108 109

	if (tp)
E
Eric Dumazet 已提交
110
		first = tp->prio - 1;
L
Linus Torvalds 已提交
111

112
	return TC_H_MAJ(first);
L
Linus Torvalds 已提交
113 114
}

115
static struct tcf_proto *tcf_proto_create(const char *kind, u32 protocol,
116
					  u32 prio, u32 parent, struct Qdisc *q,
117
					  struct tcf_chain *chain)
118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152
{
	struct tcf_proto *tp;
	int err;

	tp = kzalloc(sizeof(*tp), GFP_KERNEL);
	if (!tp)
		return ERR_PTR(-ENOBUFS);

	err = -ENOENT;
	tp->ops = tcf_proto_lookup_ops(kind);
	if (!tp->ops) {
#ifdef CONFIG_MODULES
		rtnl_unlock();
		request_module("cls_%s", kind);
		rtnl_lock();
		tp->ops = tcf_proto_lookup_ops(kind);
		/* We dropped the RTNL semaphore in order to perform
		 * the module load. So, even if we succeeded in loading
		 * the module we have to replay the request. We indicate
		 * this using -EAGAIN.
		 */
		if (tp->ops) {
			module_put(tp->ops->owner);
			err = -EAGAIN;
		} else {
			err = -ENOENT;
		}
		goto errout;
#endif
	}
	tp->classify = tp->ops->classify;
	tp->protocol = protocol;
	tp->prio = prio;
	tp->classid = parent;
	tp->q = q;
153
	tp->chain = chain;
154 155 156 157 158 159 160 161 162 163 164 165 166

	err = tp->ops->init(tp);
	if (err) {
		module_put(tp->ops->owner);
		goto errout;
	}
	return tp;

errout:
	kfree(tp);
	return ERR_PTR(err);
}

167
static void tcf_proto_destroy(struct tcf_proto *tp)
168
{
169 170 171
	tp->ops->destroy(tp);
	module_put(tp->ops->owner);
	kfree_rcu(tp, rcu);
172 173
}

174 175
static struct tcf_chain *tcf_chain_create(struct tcf_block *block,
					  u32 chain_index)
176
{
177 178 179 180 181 182 183 184
	struct tcf_chain *chain;

	chain = kzalloc(sizeof(*chain), GFP_KERNEL);
	if (!chain)
		return NULL;
	list_add_tail(&chain->list, &block->chain_list);
	chain->block = block;
	chain->index = chain_index;
185
	chain->refcnt = 1;
186
	return chain;
187 188
}

J
Jiri Pirko 已提交
189
static void tcf_chain_flush(struct tcf_chain *chain)
190 191 192
{
	struct tcf_proto *tp;

193
	if (chain->p_filter_chain)
J
Jiri Pirko 已提交
194
		RCU_INIT_POINTER(*chain->p_filter_chain, NULL);
195 196
	while ((tp = rtnl_dereference(chain->filter_chain)) != NULL) {
		RCU_INIT_POINTER(chain->filter_chain, tp->next);
197
		tcf_chain_put(chain);
198
		tcf_proto_destroy(tp);
199
	}
J
Jiri Pirko 已提交
200 201 202 203
}

static void tcf_chain_destroy(struct tcf_chain *chain)
{
204 205 206
	list_del(&chain->list);
	kfree(chain);
}
207

208 209 210
static void tcf_chain_hold(struct tcf_chain *chain)
{
	++chain->refcnt;
211 212
}

213 214
struct tcf_chain *tcf_chain_get(struct tcf_block *block, u32 chain_index,
				bool create)
215 216 217 218
{
	struct tcf_chain *chain;

	list_for_each_entry(chain, &block->chain_list, list) {
219 220 221 222
		if (chain->index == chain_index) {
			tcf_chain_hold(chain);
			return chain;
		}
223
	}
224

225
	return create ? tcf_chain_create(block, chain_index) : NULL;
226 227 228 229 230
}
EXPORT_SYMBOL(tcf_chain_get);

void tcf_chain_put(struct tcf_chain *chain)
{
231
	if (--chain->refcnt == 0)
232 233 234 235
		tcf_chain_destroy(chain);
}
EXPORT_SYMBOL(tcf_chain_put);

236 237 238 239 240
static void
tcf_chain_filter_chain_ptr_set(struct tcf_chain *chain,
			       struct tcf_proto __rcu **p_filter_chain)
{
	chain->p_filter_chain = p_filter_chain;
241
}
242

243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272
static void tcf_block_offload_cmd(struct tcf_block *block, struct Qdisc *q,
				  struct tcf_block_ext_info *ei,
				  enum tc_block_command command)
{
	struct net_device *dev = q->dev_queue->dev;
	struct tc_block_offload bo = {};

	if (!tc_can_offload(dev))
		return;
	bo.command = command;
	bo.binder_type = ei->binder_type;
	bo.block = block;
	dev->netdev_ops->ndo_setup_tc(dev, TC_SETUP_BLOCK, &bo);
}

static void tcf_block_offload_bind(struct tcf_block *block, struct Qdisc *q,
				   struct tcf_block_ext_info *ei)
{
	tcf_block_offload_cmd(block, q, ei, TC_BLOCK_BIND);
}

static void tcf_block_offload_unbind(struct tcf_block *block, struct Qdisc *q,
				     struct tcf_block_ext_info *ei)
{
	tcf_block_offload_cmd(block, q, ei, TC_BLOCK_UNBIND);
}

int tcf_block_get_ext(struct tcf_block **p_block,
		      struct tcf_proto __rcu **p_filter_chain, struct Qdisc *q,
		      struct tcf_block_ext_info *ei)
273 274
{
	struct tcf_block *block = kzalloc(sizeof(*block), GFP_KERNEL);
275
	struct tcf_chain *chain;
276
	int err;
277 278 279

	if (!block)
		return -ENOMEM;
280
	INIT_LIST_HEAD(&block->chain_list);
281 282
	INIT_LIST_HEAD(&block->cb_list);

283 284 285
	/* Create chain 0 by default, it has to be always present. */
	chain = tcf_chain_create(block, 0);
	if (!chain) {
286 287 288
		err = -ENOMEM;
		goto err_chain_create;
	}
289
	tcf_chain_filter_chain_ptr_set(chain, p_filter_chain);
290
	block->net = qdisc_net(q);
291
	block->q = q;
292
	tcf_block_offload_bind(block, q, ei);
293 294
	*p_block = block;
	return 0;
295 296 297 298

err_chain_create:
	kfree(block);
	return err;
299
}
300 301 302 303 304 305 306 307 308
EXPORT_SYMBOL(tcf_block_get_ext);

int tcf_block_get(struct tcf_block **p_block,
		  struct tcf_proto __rcu **p_filter_chain, struct Qdisc *q)
{
	struct tcf_block_ext_info ei = {0, };

	return tcf_block_get_ext(p_block, p_filter_chain, q, &ei);
}
309 310
EXPORT_SYMBOL(tcf_block_get);

311 312 313
void tcf_block_put_ext(struct tcf_block *block,
		       struct tcf_proto __rcu **p_filter_chain, struct Qdisc *q,
		       struct tcf_block_ext_info *ei)
314
{
315 316
	struct tcf_chain *chain, *tmp;

317 318
	if (!block)
		return;
319

320 321
	tcf_block_offload_unbind(block, q, ei);

322 323
	/* XXX: Standalone actions are not allowed to jump to any chain, and
	 * bound actions should be all removed after flushing. However,
324 325 326
	 * filters are destroyed in RCU callbacks, we have to hold the chains
	 * first, otherwise we would always race with RCU callbacks on this list
	 * without proper locking.
327
	 */
328 329 330 331 332 333 334 335 336 337 338

	/* Wait for existing RCU callbacks to cool down. */
	rcu_barrier();

	/* Hold a refcnt for all chains, except 0, in case they are gone. */
	list_for_each_entry(chain, &block->chain_list, list)
		if (chain->index)
			tcf_chain_hold(chain);

	/* No race on the list, because no chain could be destroyed. */
	list_for_each_entry(chain, &block->chain_list, list)
339
		tcf_chain_flush(chain);
340

341 342 343 344
	/* Wait for RCU callbacks to release the reference count. */
	rcu_barrier();

	/* At this point, all the chains should have refcnt == 1. */
345 346
	list_for_each_entry_safe(chain, tmp, &block->chain_list, list)
		tcf_chain_put(chain);
347 348
	kfree(block);
}
349 350 351 352 353 354 355 356
EXPORT_SYMBOL(tcf_block_put_ext);

void tcf_block_put(struct tcf_block *block)
{
	struct tcf_block_ext_info ei = {0, };

	tcf_block_put_ext(block, NULL, block->q, &ei);
}
357
EXPORT_SYMBOL(tcf_block_put);
358

359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461
struct tcf_block_cb {
	struct list_head list;
	tc_setup_cb_t *cb;
	void *cb_ident;
	void *cb_priv;
	unsigned int refcnt;
};

void *tcf_block_cb_priv(struct tcf_block_cb *block_cb)
{
	return block_cb->cb_priv;
}
EXPORT_SYMBOL(tcf_block_cb_priv);

struct tcf_block_cb *tcf_block_cb_lookup(struct tcf_block *block,
					 tc_setup_cb_t *cb, void *cb_ident)
{	struct tcf_block_cb *block_cb;

	list_for_each_entry(block_cb, &block->cb_list, list)
		if (block_cb->cb == cb && block_cb->cb_ident == cb_ident)
			return block_cb;
	return NULL;
}
EXPORT_SYMBOL(tcf_block_cb_lookup);

void tcf_block_cb_incref(struct tcf_block_cb *block_cb)
{
	block_cb->refcnt++;
}
EXPORT_SYMBOL(tcf_block_cb_incref);

unsigned int tcf_block_cb_decref(struct tcf_block_cb *block_cb)
{
	return --block_cb->refcnt;
}
EXPORT_SYMBOL(tcf_block_cb_decref);

struct tcf_block_cb *__tcf_block_cb_register(struct tcf_block *block,
					     tc_setup_cb_t *cb, void *cb_ident,
					     void *cb_priv)
{
	struct tcf_block_cb *block_cb;

	block_cb = kzalloc(sizeof(*block_cb), GFP_KERNEL);
	if (!block_cb)
		return NULL;
	block_cb->cb = cb;
	block_cb->cb_ident = cb_ident;
	block_cb->cb_priv = cb_priv;
	list_add(&block_cb->list, &block->cb_list);
	return block_cb;
}
EXPORT_SYMBOL(__tcf_block_cb_register);

int tcf_block_cb_register(struct tcf_block *block,
			  tc_setup_cb_t *cb, void *cb_ident,
			  void *cb_priv)
{
	struct tcf_block_cb *block_cb;

	block_cb = __tcf_block_cb_register(block, cb, cb_ident, cb_priv);
	return block_cb ? 0 : -ENOMEM;
}
EXPORT_SYMBOL(tcf_block_cb_register);

void __tcf_block_cb_unregister(struct tcf_block_cb *block_cb)
{
	list_del(&block_cb->list);
	kfree(block_cb);
}
EXPORT_SYMBOL(__tcf_block_cb_unregister);

void tcf_block_cb_unregister(struct tcf_block *block,
			     tc_setup_cb_t *cb, void *cb_ident)
{
	struct tcf_block_cb *block_cb;

	block_cb = tcf_block_cb_lookup(block, cb, cb_ident);
	if (!block_cb)
		return;
	__tcf_block_cb_unregister(block_cb);
}
EXPORT_SYMBOL(tcf_block_cb_unregister);

static int tcf_block_cb_call(struct tcf_block *block, enum tc_setup_type type,
			     void *type_data, bool err_stop)
{
	struct tcf_block_cb *block_cb;
	int ok_count = 0;
	int err;

	list_for_each_entry(block_cb, &block->cb_list, list) {
		err = block_cb->cb(type, type_data, block_cb->cb_priv);
		if (err) {
			if (err_stop)
				return err;
		} else {
			ok_count++;
		}
	}
	return ok_count;
}

462 463 464 465 466 467 468 469 470 471
/* Main classifier routine: scans classifier chain attached
 * to this qdisc, (optionally) tests for protocol and asks
 * specific classifiers.
 */
int tcf_classify(struct sk_buff *skb, const struct tcf_proto *tp,
		 struct tcf_result *res, bool compat_mode)
{
	__be16 protocol = tc_skb_protocol(skb);
#ifdef CONFIG_NET_CLS_ACT
	const int max_reclassify_loop = 4;
472 473
	const struct tcf_proto *orig_tp = tp;
	const struct tcf_proto *first_tp;
474 475 476 477 478 479 480 481 482 483 484 485 486
	int limit = 0;

reclassify:
#endif
	for (; tp; tp = rcu_dereference_bh(tp->next)) {
		int err;

		if (tp->protocol != protocol &&
		    tp->protocol != htons(ETH_P_ALL))
			continue;

		err = tp->classify(skb, tp, res);
#ifdef CONFIG_NET_CLS_ACT
487
		if (unlikely(err == TC_ACT_RECLASSIFY && !compat_mode)) {
488
			first_tp = orig_tp;
489
			goto reset;
490
		} else if (unlikely(TC_ACT_EXT_CMP(err, TC_ACT_GOTO_CHAIN))) {
491
			first_tp = res->goto_tp;
492 493
			goto reset;
		}
494 495 496 497 498 499 500 501 502 503 504 505 506 507 508
#endif
		if (err >= 0)
			return err;
	}

	return TC_ACT_UNSPEC; /* signal: continue lookup */
#ifdef CONFIG_NET_CLS_ACT
reset:
	if (unlikely(limit++ >= max_reclassify_loop)) {
		net_notice_ratelimited("%s: reclassify loop, rule prio %u, protocol %02x\n",
				       tp->q->ops->id, tp->prio & 0xffff,
				       ntohs(tp->protocol));
		return TC_ACT_SHOT;
	}

509
	tp = first_tp;
510 511 512 513 514 515
	protocol = tc_skb_protocol(skb);
	goto reclassify;
#endif
}
EXPORT_SYMBOL(tcf_classify);

516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531
struct tcf_chain_info {
	struct tcf_proto __rcu **pprev;
	struct tcf_proto __rcu *next;
};

static struct tcf_proto *tcf_chain_tp_prev(struct tcf_chain_info *chain_info)
{
	return rtnl_dereference(*chain_info->pprev);
}

static void tcf_chain_tp_insert(struct tcf_chain *chain,
				struct tcf_chain_info *chain_info,
				struct tcf_proto *tp)
{
	if (chain->p_filter_chain &&
	    *chain_info->pprev == chain->filter_chain)
532
		rcu_assign_pointer(*chain->p_filter_chain, tp);
533 534
	RCU_INIT_POINTER(tp->next, tcf_chain_tp_prev(chain_info));
	rcu_assign_pointer(*chain_info->pprev, tp);
535
	tcf_chain_hold(chain);
536 537 538 539 540 541 542 543 544
}

static void tcf_chain_tp_remove(struct tcf_chain *chain,
				struct tcf_chain_info *chain_info,
				struct tcf_proto *tp)
{
	struct tcf_proto *next = rtnl_dereference(chain_info->next);

	if (chain->p_filter_chain && tp == chain->filter_chain)
545
		RCU_INIT_POINTER(*chain->p_filter_chain, next);
546
	RCU_INIT_POINTER(*chain_info->pprev, next);
547
	tcf_chain_put(chain);
548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576
}

static struct tcf_proto *tcf_chain_tp_find(struct tcf_chain *chain,
					   struct tcf_chain_info *chain_info,
					   u32 protocol, u32 prio,
					   bool prio_allocate)
{
	struct tcf_proto **pprev;
	struct tcf_proto *tp;

	/* Check the chain for existence of proto-tcf with this priority */
	for (pprev = &chain->filter_chain;
	     (tp = rtnl_dereference(*pprev)); pprev = &tp->next) {
		if (tp->prio >= prio) {
			if (tp->prio == prio) {
				if (prio_allocate ||
				    (tp->protocol != protocol && protocol))
					return ERR_PTR(-EINVAL);
			} else {
				tp = NULL;
			}
			break;
		}
	}
	chain_info->pprev = pprev;
	chain_info->next = tp ? tp->next : NULL;
	return tp;
}

577
static int tcf_fill_node(struct net *net, struct sk_buff *skb,
578 579
			 struct tcf_proto *tp, struct Qdisc *q, u32 parent,
			 void *fh, u32 portid, u32 seq, u16 flags, int event)
580 581 582 583 584 585 586 587 588 589 590 591
{
	struct tcmsg *tcm;
	struct nlmsghdr  *nlh;
	unsigned char *b = skb_tail_pointer(skb);

	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*tcm), flags);
	if (!nlh)
		goto out_nlmsg_trim;
	tcm = nlmsg_data(nlh);
	tcm->tcm_family = AF_UNSPEC;
	tcm->tcm__pad1 = 0;
	tcm->tcm__pad2 = 0;
592 593
	tcm->tcm_ifindex = qdisc_dev(q)->ifindex;
	tcm->tcm_parent = parent;
594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615
	tcm->tcm_info = TC_H_MAKE(tp->prio, tp->protocol);
	if (nla_put_string(skb, TCA_KIND, tp->ops->kind))
		goto nla_put_failure;
	if (nla_put_u32(skb, TCA_CHAIN, tp->chain->index))
		goto nla_put_failure;
	if (!fh) {
		tcm->tcm_handle = 0;
	} else {
		if (tp->ops->dump && tp->ops->dump(net, tp, fh, skb, tcm) < 0)
			goto nla_put_failure;
	}
	nlh->nlmsg_len = skb_tail_pointer(skb) - b;
	return skb->len;

out_nlmsg_trim:
nla_put_failure:
	nlmsg_trim(skb, b);
	return -1;
}

static int tfilter_notify(struct net *net, struct sk_buff *oskb,
			  struct nlmsghdr *n, struct tcf_proto *tp,
616
			  struct Qdisc *q, u32 parent,
617 618 619 620 621 622 623 624 625
			  void *fh, int event, bool unicast)
{
	struct sk_buff *skb;
	u32 portid = oskb ? NETLINK_CB(oskb).portid : 0;

	skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
	if (!skb)
		return -ENOBUFS;

626
	if (tcf_fill_node(net, skb, tp, q, parent, fh, portid, n->nlmsg_seq,
627 628 629 630 631 632 633 634 635 636 637 638 639 640
			  n->nlmsg_flags, event) <= 0) {
		kfree_skb(skb);
		return -EINVAL;
	}

	if (unicast)
		return netlink_unicast(net->rtnl, skb, portid, MSG_DONTWAIT);

	return rtnetlink_send(skb, net, portid, RTNLGRP_TC,
			      n->nlmsg_flags & NLM_F_ECHO);
}

static int tfilter_del_notify(struct net *net, struct sk_buff *oskb,
			      struct nlmsghdr *n, struct tcf_proto *tp,
641
			      struct Qdisc *q, u32 parent,
642 643 644 645 646 647 648 649 650 651
			      void *fh, bool unicast, bool *last)
{
	struct sk_buff *skb;
	u32 portid = oskb ? NETLINK_CB(oskb).portid : 0;
	int err;

	skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
	if (!skb)
		return -ENOBUFS;

652
	if (tcf_fill_node(net, skb, tp, q, parent, fh, portid, n->nlmsg_seq,
653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671
			  n->nlmsg_flags, RTM_DELTFILTER) <= 0) {
		kfree_skb(skb);
		return -EINVAL;
	}

	err = tp->ops->delete(tp, fh, last);
	if (err) {
		kfree_skb(skb);
		return err;
	}

	if (unicast)
		return netlink_unicast(net->rtnl, skb, portid, MSG_DONTWAIT);

	return rtnetlink_send(skb, net, portid, RTNLGRP_TC,
			      n->nlmsg_flags & NLM_F_ECHO);
}

static void tfilter_notify_chain(struct net *net, struct sk_buff *oskb,
672
				 struct Qdisc *q, u32 parent,
673 674 675 676 677 678 679
				 struct nlmsghdr *n,
				 struct tcf_chain *chain, int event)
{
	struct tcf_proto *tp;

	for (tp = rtnl_dereference(chain->filter_chain);
	     tp; tp = rtnl_dereference(tp->next))
680
		tfilter_notify(net, oskb, n, tp, q, parent, 0, event, false);
681 682
}

L
Linus Torvalds 已提交
683 684
/* Add/change/delete/get a filter node */

685 686
static int tc_ctl_tfilter(struct sk_buff *skb, struct nlmsghdr *n,
			  struct netlink_ext_ack *extack)
L
Linus Torvalds 已提交
687
{
688
	struct net *net = sock_net(skb->sk);
689
	struct nlattr *tca[TCA_MAX + 1];
L
Linus Torvalds 已提交
690 691 692
	struct tcmsg *t;
	u32 protocol;
	u32 prio;
693
	bool prio_allocate;
L
Linus Torvalds 已提交
694
	u32 parent;
695
	u32 chain_index;
L
Linus Torvalds 已提交
696 697
	struct net_device *dev;
	struct Qdisc  *q;
698
	struct tcf_chain_info chain_info;
699
	struct tcf_chain *chain = NULL;
700
	struct tcf_block *block;
L
Linus Torvalds 已提交
701
	struct tcf_proto *tp;
702
	const struct Qdisc_class_ops *cops;
L
Linus Torvalds 已提交
703
	unsigned long cl;
704
	void *fh;
L
Linus Torvalds 已提交
705
	int err;
706
	int tp_created;
L
Linus Torvalds 已提交
707

708
	if ((n->nlmsg_type != RTM_GETTFILTER) &&
709
	    !netlink_ns_capable(skb, net->user_ns, CAP_NET_ADMIN))
710
		return -EPERM;
711

L
Linus Torvalds 已提交
712
replay:
713 714
	tp_created = 0;

715
	err = nlmsg_parse(n, sizeof(*t), tca, TCA_MAX, NULL, extack);
716 717 718
	if (err < 0)
		return err;

719
	t = nlmsg_data(n);
L
Linus Torvalds 已提交
720 721
	protocol = TC_H_MIN(t->tcm_info);
	prio = TC_H_MAJ(t->tcm_info);
722
	prio_allocate = false;
L
Linus Torvalds 已提交
723 724 725 726
	parent = t->tcm_parent;
	cl = 0;

	if (prio == 0) {
727 728
		switch (n->nlmsg_type) {
		case RTM_DELTFILTER:
729
			if (protocol || t->tcm_handle || tca[TCA_KIND])
730 731 732 733 734 735 736 737
				return -ENOENT;
			break;
		case RTM_NEWTFILTER:
			/* If no priority is provided by the user,
			 * we allocate one.
			 */
			if (n->nlmsg_flags & NLM_F_CREATE) {
				prio = TC_H_MAKE(0x80000000U, 0U);
738
				prio_allocate = true;
739 740 741 742
				break;
			}
			/* fall-through */
		default:
L
Linus Torvalds 已提交
743
			return -ENOENT;
744
		}
L
Linus Torvalds 已提交
745 746 747 748 749
	}

	/* Find head of filter chain. */

	/* Find link */
750
	dev = __dev_get_by_index(net, t->tcm_ifindex);
751
	if (dev == NULL)
L
Linus Torvalds 已提交
752 753 754 755
		return -ENODEV;

	/* Find qdisc */
	if (!parent) {
756
		q = dev->qdisc;
L
Linus Torvalds 已提交
757
		parent = q->handle;
758 759 760 761 762
	} else {
		q = qdisc_lookup(dev, TC_H_MAJ(t->tcm_parent));
		if (q == NULL)
			return -EINVAL;
	}
L
Linus Torvalds 已提交
763 764

	/* Is it classful? */
E
Eric Dumazet 已提交
765 766
	cops = q->ops->cl_ops;
	if (!cops)
L
Linus Torvalds 已提交
767 768
		return -EINVAL;

769
	if (!cops->tcf_block)
770 771
		return -EOPNOTSUPP;

L
Linus Torvalds 已提交
772 773
	/* Do we search for filter, attached to class? */
	if (TC_H_MIN(parent)) {
774
		cl = cops->find(q, parent);
L
Linus Torvalds 已提交
775 776 777 778 779
		if (cl == 0)
			return -ENOENT;
	}

	/* And the last stroke */
780 781
	block = cops->tcf_block(q, cl);
	if (!block) {
782
		err = -EINVAL;
L
Linus Torvalds 已提交
783
		goto errout;
784
	}
785 786 787 788 789 790

	chain_index = tca[TCA_CHAIN] ? nla_get_u32(tca[TCA_CHAIN]) : 0;
	if (chain_index > TC_ACT_EXT_VAL_MASK) {
		err = -EINVAL;
		goto errout;
	}
791 792
	chain = tcf_chain_get(block, chain_index,
			      n->nlmsg_type == RTM_NEWTFILTER);
793
	if (!chain) {
794
		err = n->nlmsg_type == RTM_NEWTFILTER ? -ENOMEM : -EINVAL;
795 796
		goto errout;
	}
797

798
	if (n->nlmsg_type == RTM_DELTFILTER && prio == 0) {
799 800
		tfilter_notify_chain(net, skb, q, parent, n,
				     chain, RTM_DELTFILTER);
J
Jiri Pirko 已提交
801
		tcf_chain_flush(chain);
802 803 804
		err = 0;
		goto errout;
	}
L
Linus Torvalds 已提交
805

806 807 808 809 810
	tp = tcf_chain_tp_find(chain, &chain_info, protocol,
			       prio, prio_allocate);
	if (IS_ERR(tp)) {
		err = PTR_ERR(tp);
		goto errout;
L
Linus Torvalds 已提交
811 812 813 814 815
	}

	if (tp == NULL) {
		/* Proto-tcf does not exist, create new one */

816 817
		if (tca[TCA_KIND] == NULL || !protocol) {
			err = -EINVAL;
L
Linus Torvalds 已提交
818
			goto errout;
819
		}
L
Linus Torvalds 已提交
820

E
Eric Dumazet 已提交
821
		if (n->nlmsg_type != RTM_NEWTFILTER ||
822 823
		    !(n->nlmsg_flags & NLM_F_CREATE)) {
			err = -ENOENT;
L
Linus Torvalds 已提交
824
			goto errout;
825
		}
L
Linus Torvalds 已提交
826

827
		if (prio_allocate)
828
			prio = tcf_auto_prio(tcf_chain_tp_prev(&chain_info));
L
Linus Torvalds 已提交
829

830
		tp = tcf_proto_create(nla_data(tca[TCA_KIND]),
831
				      protocol, prio, parent, q, chain);
832 833
		if (IS_ERR(tp)) {
			err = PTR_ERR(tp);
L
Linus Torvalds 已提交
834 835
			goto errout;
		}
836
		tp_created = 1;
837 838
	} else if (tca[TCA_KIND] && nla_strcmp(tca[TCA_KIND], tp->ops->kind)) {
		err = -EINVAL;
L
Linus Torvalds 已提交
839
		goto errout;
840
	}
L
Linus Torvalds 已提交
841 842 843

	fh = tp->ops->get(tp, t->tcm_handle);

844
	if (!fh) {
L
Linus Torvalds 已提交
845
		if (n->nlmsg_type == RTM_DELTFILTER && t->tcm_handle == 0) {
846
			tcf_chain_tp_remove(chain, &chain_info, tp);
847
			tfilter_notify(net, skb, n, tp, q, parent, fh,
848
				       RTM_DELTFILTER, false);
849
			tcf_proto_destroy(tp);
L
Linus Torvalds 已提交
850 851 852 853
			err = 0;
			goto errout;
		}

854
		if (n->nlmsg_type != RTM_NEWTFILTER ||
855 856
		    !(n->nlmsg_flags & NLM_F_CREATE)) {
			err = -ENOENT;
L
Linus Torvalds 已提交
857
			goto errout;
858
		}
L
Linus Torvalds 已提交
859
	} else {
860 861
		bool last;

L
Linus Torvalds 已提交
862
		switch (n->nlmsg_type) {
863
		case RTM_NEWTFILTER:
864 865
			if (n->nlmsg_flags & NLM_F_EXCL) {
				if (tp_created)
866
					tcf_proto_destroy(tp);
867
				err = -EEXIST;
L
Linus Torvalds 已提交
868
				goto errout;
869
			}
L
Linus Torvalds 已提交
870 871
			break;
		case RTM_DELTFILTER:
872 873
			err = tfilter_del_notify(net, skb, n, tp, q, parent,
						 fh, false, &last);
874 875
			if (err)
				goto errout;
876
			if (last) {
877
				tcf_chain_tp_remove(chain, &chain_info, tp);
878 879
				tcf_proto_destroy(tp);
			}
880
			goto errout;
L
Linus Torvalds 已提交
881
		case RTM_GETTFILTER:
882
			err = tfilter_notify(net, skb, n, tp, q, parent, fh,
883
					     RTM_NEWTFILTER, true);
L
Linus Torvalds 已提交
884 885 886 887 888 889 890
			goto errout;
		default:
			err = -EINVAL;
			goto errout;
		}
	}

891 892
	err = tp->ops->change(net, skb, tp, cl, t->tcm_handle, tca, &fh,
			      n->nlmsg_flags & NLM_F_CREATE ? TCA_ACT_NOREPLACE : TCA_ACT_REPLACE);
893
	if (err == 0) {
894 895
		if (tp_created)
			tcf_chain_tp_insert(chain, &chain_info, tp);
896 897
		tfilter_notify(net, skb, n, tp, q, parent, fh,
			       RTM_NEWTFILTER, false);
898 899
	} else {
		if (tp_created)
900
			tcf_proto_destroy(tp);
901
	}
L
Linus Torvalds 已提交
902 903

errout:
904 905
	if (chain)
		tcf_chain_put(chain);
L
Linus Torvalds 已提交
906 907 908 909 910 911
	if (err == -EAGAIN)
		/* Replay the request. */
		goto replay;
	return err;
}

912
struct tcf_dump_args {
L
Linus Torvalds 已提交
913 914 915
	struct tcf_walker w;
	struct sk_buff *skb;
	struct netlink_callback *cb;
916 917
	struct Qdisc *q;
	u32 parent;
L
Linus Torvalds 已提交
918 919
};

920
static int tcf_node_dump(struct tcf_proto *tp, void *n, struct tcf_walker *arg)
L
Linus Torvalds 已提交
921
{
922
	struct tcf_dump_args *a = (void *)arg;
923
	struct net *net = sock_net(a->skb->sk);
L
Linus Torvalds 已提交
924

925 926
	return tcf_fill_node(net, a->skb, tp, a->q, a->parent,
			     n, NETLINK_CB(a->cb->skb).portid,
J
Jamal Hadi Salim 已提交
927 928
			     a->cb->nlh->nlmsg_seq, NLM_F_MULTI,
			     RTM_NEWTFILTER);
L
Linus Torvalds 已提交
929 930
}

931 932
static bool tcf_chain_dump(struct tcf_chain *chain, struct Qdisc *q, u32 parent,
			   struct sk_buff *skb, struct netlink_callback *cb,
933 934 935 936 937 938 939 940 941 942 943 944 945 946 947 948 949 950 951 952 953
			   long index_start, long *p_index)
{
	struct net *net = sock_net(skb->sk);
	struct tcmsg *tcm = nlmsg_data(cb->nlh);
	struct tcf_dump_args arg;
	struct tcf_proto *tp;

	for (tp = rtnl_dereference(chain->filter_chain);
	     tp; tp = rtnl_dereference(tp->next), (*p_index)++) {
		if (*p_index < index_start)
			continue;
		if (TC_H_MAJ(tcm->tcm_info) &&
		    TC_H_MAJ(tcm->tcm_info) != tp->prio)
			continue;
		if (TC_H_MIN(tcm->tcm_info) &&
		    TC_H_MIN(tcm->tcm_info) != tp->protocol)
			continue;
		if (*p_index > index_start)
			memset(&cb->args[1], 0,
			       sizeof(cb->args) - sizeof(cb->args[0]));
		if (cb->args[1] == 0) {
954
			if (tcf_fill_node(net, skb, tp, q, parent, 0,
955 956 957
					  NETLINK_CB(cb->skb).portid,
					  cb->nlh->nlmsg_seq, NLM_F_MULTI,
					  RTM_NEWTFILTER) <= 0)
958
				return false;
959 960 961 962 963 964 965 966

			cb->args[1] = 1;
		}
		if (!tp->ops->walk)
			continue;
		arg.w.fn = tcf_node_dump;
		arg.skb = skb;
		arg.cb = cb;
967 968
		arg.q = q;
		arg.parent = parent;
969 970 971 972 973 974
		arg.w.stop = 0;
		arg.w.skip = cb->args[1] - 1;
		arg.w.count = 0;
		tp->ops->walk(tp, &arg.w);
		cb->args[1] = arg.w.count + 1;
		if (arg.w.stop)
975
			return false;
976
	}
977
	return true;
978 979
}

E
Eric Dumazet 已提交
980
/* called with RTNL */
L
Linus Torvalds 已提交
981 982
static int tc_dump_tfilter(struct sk_buff *skb, struct netlink_callback *cb)
{
983
	struct net *net = sock_net(skb->sk);
984
	struct nlattr *tca[TCA_MAX + 1];
L
Linus Torvalds 已提交
985 986
	struct net_device *dev;
	struct Qdisc *q;
987
	struct tcf_block *block;
988
	struct tcf_chain *chain;
989
	struct tcmsg *tcm = nlmsg_data(cb->nlh);
L
Linus Torvalds 已提交
990
	unsigned long cl = 0;
991
	const struct Qdisc_class_ops *cops;
992 993
	long index_start;
	long index;
994
	u32 parent;
995
	int err;
L
Linus Torvalds 已提交
996

997
	if (nlmsg_len(cb->nlh) < sizeof(*tcm))
L
Linus Torvalds 已提交
998
		return skb->len;
999 1000 1001 1002 1003

	err = nlmsg_parse(cb->nlh, sizeof(*tcm), tca, TCA_MAX, NULL, NULL);
	if (err)
		return err;

E
Eric Dumazet 已提交
1004 1005
	dev = __dev_get_by_index(net, tcm->tcm_ifindex);
	if (!dev)
L
Linus Torvalds 已提交
1006 1007
		return skb->len;

1008 1009
	parent = tcm->tcm_parent;
	if (!parent) {
1010
		q = dev->qdisc;
1011 1012
		parent = q->handle;
	} else {
L
Linus Torvalds 已提交
1013
		q = qdisc_lookup(dev, TC_H_MAJ(tcm->tcm_parent));
1014
	}
L
Linus Torvalds 已提交
1015 1016
	if (!q)
		goto out;
E
Eric Dumazet 已提交
1017 1018
	cops = q->ops->cl_ops;
	if (!cops)
1019
		goto out;
1020
	if (!cops->tcf_block)
1021
		goto out;
L
Linus Torvalds 已提交
1022
	if (TC_H_MIN(tcm->tcm_parent)) {
1023
		cl = cops->find(q, tcm->tcm_parent);
L
Linus Torvalds 已提交
1024
		if (cl == 0)
1025
			goto out;
L
Linus Torvalds 已提交
1026
	}
1027 1028
	block = cops->tcf_block(q, cl);
	if (!block)
1029
		goto out;
L
Linus Torvalds 已提交
1030

1031 1032
	index_start = cb->args[0];
	index = 0;
1033 1034 1035 1036 1037

	list_for_each_entry(chain, &block->chain_list, list) {
		if (tca[TCA_CHAIN] &&
		    nla_get_u32(tca[TCA_CHAIN]) != chain->index)
			continue;
1038 1039
		if (!tcf_chain_dump(chain, q, parent, skb, cb,
				    index_start, &index))
1040 1041 1042
			break;
	}

1043
	cb->args[0] = index;
L
Linus Torvalds 已提交
1044 1045 1046 1047 1048

out:
	return skb->len;
}

1049
void tcf_exts_destroy(struct tcf_exts *exts)
L
Linus Torvalds 已提交
1050 1051
{
#ifdef CONFIG_NET_CLS_ACT
1052 1053 1054 1055 1056 1057
	LIST_HEAD(actions);

	tcf_exts_to_list(exts, &actions);
	tcf_action_destroy(&actions, TCA_ACT_UNBIND);
	kfree(exts->actions);
	exts->nr_actions = 0;
L
Linus Torvalds 已提交
1058 1059
#endif
}
1060
EXPORT_SYMBOL(tcf_exts_destroy);
L
Linus Torvalds 已提交
1061

1062
int tcf_exts_validate(struct net *net, struct tcf_proto *tp, struct nlattr **tb,
J
Jamal Hadi Salim 已提交
1063
		      struct nlattr *rate_tlv, struct tcf_exts *exts, bool ovr)
L
Linus Torvalds 已提交
1064 1065 1066 1067 1068
{
#ifdef CONFIG_NET_CLS_ACT
	{
		struct tc_action *act;

1069
		if (exts->police && tb[exts->police]) {
1070 1071 1072
			act = tcf_action_init_1(net, tp, tb[exts->police],
						rate_tlv, "police", ovr,
						TCA_ACT_BIND);
1073 1074
			if (IS_ERR(act))
				return PTR_ERR(act);
L
Linus Torvalds 已提交
1075

1076
			act->type = exts->type = TCA_OLD_COMPAT;
1077 1078
			exts->actions[0] = act;
			exts->nr_actions = 1;
1079
		} else if (exts->action && tb[exts->action]) {
1080 1081 1082
			LIST_HEAD(actions);
			int err, i = 0;

1083 1084
			err = tcf_action_init(net, tp, tb[exts->action],
					      rate_tlv, NULL, ovr, TCA_ACT_BIND,
J
Jamal Hadi Salim 已提交
1085
					      &actions);
1086 1087
			if (err)
				return err;
1088 1089 1090
			list_for_each_entry(act, &actions, list)
				exts->actions[i++] = act;
			exts->nr_actions = i;
L
Linus Torvalds 已提交
1091 1092 1093
		}
	}
#else
1094 1095
	if ((exts->action && tb[exts->action]) ||
	    (exts->police && tb[exts->police]))
L
Linus Torvalds 已提交
1096 1097 1098 1099 1100
		return -EOPNOTSUPP;
#endif

	return 0;
}
1101
EXPORT_SYMBOL(tcf_exts_validate);
L
Linus Torvalds 已提交
1102

1103
void tcf_exts_change(struct tcf_exts *dst, struct tcf_exts *src)
L
Linus Torvalds 已提交
1104 1105
{
#ifdef CONFIG_NET_CLS_ACT
1106 1107
	struct tcf_exts old = *dst;

1108
	*dst = *src;
1109
	tcf_exts_destroy(&old);
L
Linus Torvalds 已提交
1110 1111
#endif
}
1112
EXPORT_SYMBOL(tcf_exts_change);
L
Linus Torvalds 已提交
1113

1114 1115 1116 1117 1118 1119 1120 1121 1122
#ifdef CONFIG_NET_CLS_ACT
static struct tc_action *tcf_exts_first_act(struct tcf_exts *exts)
{
	if (exts->nr_actions == 0)
		return NULL;
	else
		return exts->actions[0];
}
#endif
1123

1124
int tcf_exts_dump(struct sk_buff *skb, struct tcf_exts *exts)
L
Linus Torvalds 已提交
1125 1126
{
#ifdef CONFIG_NET_CLS_ACT
1127 1128
	struct nlattr *nest;

1129
	if (exts->action && tcf_exts_has_actions(exts)) {
L
Linus Torvalds 已提交
1130 1131 1132 1133 1134
		/*
		 * again for backward compatible mode - we want
		 * to work with both old and new modes of entering
		 * tc data even if iproute2  was newer - jhs
		 */
1135
		if (exts->type != TCA_OLD_COMPAT) {
1136 1137
			LIST_HEAD(actions);

1138
			nest = nla_nest_start(skb, exts->action);
1139 1140
			if (nest == NULL)
				goto nla_put_failure;
1141 1142 1143

			tcf_exts_to_list(exts, &actions);
			if (tcf_action_dump(skb, &actions, 0, 0) < 0)
1144
				goto nla_put_failure;
1145
			nla_nest_end(skb, nest);
1146
		} else if (exts->police) {
1147
			struct tc_action *act = tcf_exts_first_act(exts);
1148
			nest = nla_nest_start(skb, exts->police);
1149
			if (nest == NULL || !act)
1150
				goto nla_put_failure;
1151
			if (tcf_action_dump_old(skb, act, 0, 0) < 0)
1152
				goto nla_put_failure;
1153
			nla_nest_end(skb, nest);
L
Linus Torvalds 已提交
1154 1155 1156
		}
	}
	return 0;
1157 1158 1159

nla_put_failure:
	nla_nest_cancel(skb, nest);
L
Linus Torvalds 已提交
1160
	return -1;
1161 1162 1163
#else
	return 0;
#endif
L
Linus Torvalds 已提交
1164
}
1165
EXPORT_SYMBOL(tcf_exts_dump);
L
Linus Torvalds 已提交
1166

1167

1168
int tcf_exts_dump_stats(struct sk_buff *skb, struct tcf_exts *exts)
L
Linus Torvalds 已提交
1169 1170
{
#ifdef CONFIG_NET_CLS_ACT
1171
	struct tc_action *a = tcf_exts_first_act(exts);
1172
	if (a != NULL && tcf_action_copy_stats(skb, a, 1) < 0)
1173
		return -1;
L
Linus Torvalds 已提交
1174 1175 1176
#endif
	return 0;
}
1177
EXPORT_SYMBOL(tcf_exts_dump_stats);
L
Linus Torvalds 已提交
1178

1179 1180 1181
static int tc_exts_setup_cb_egdev_call(struct tcf_exts *exts,
				       enum tc_setup_type type,
				       void *type_data, bool err_stop)
1182 1183 1184 1185 1186 1187 1188 1189 1190 1191 1192 1193 1194 1195 1196 1197 1198 1199 1200 1201 1202 1203 1204 1205 1206 1207
{
	int ok_count = 0;
#ifdef CONFIG_NET_CLS_ACT
	const struct tc_action *a;
	struct net_device *dev;
	LIST_HEAD(actions);
	int ret;

	if (!tcf_exts_has_actions(exts))
		return 0;

	tcf_exts_to_list(exts, &actions);
	list_for_each_entry(a, &actions, list) {
		if (!a->ops->get_dev)
			continue;
		dev = a->ops->get_dev(a);
		if (!dev || !tc_can_offload(dev))
			continue;
		ret = tc_setup_cb_egdev_call(dev, type, type_data, err_stop);
		if (ret < 0)
			return ret;
		ok_count += ret;
	}
#endif
	return ok_count;
}
1208

1209 1210
int tc_setup_cb_call(struct tcf_block *block, struct tcf_exts *exts,
		     enum tc_setup_type type, void *type_data, bool err_stop)
1211
{
1212 1213 1214 1215 1216 1217 1218 1219 1220 1221 1222 1223 1224 1225 1226 1227
	int ok_count;
	int ret;

	ret = tcf_block_cb_call(block, type, type_data, err_stop);
	if (ret < 0)
		return ret;
	ok_count = ret;

	if (!exts)
		return ok_count;
	ret = tc_exts_setup_cb_egdev_call(exts, type, type_data, err_stop);
	if (ret < 0)
		return ret;
	ok_count += ret;

	return ok_count;
1228 1229
}
EXPORT_SYMBOL(tc_setup_cb_call);
1230

L
Linus Torvalds 已提交
1231 1232
static int __init tc_filter_init(void)
{
1233 1234
	rtnl_register(PF_UNSPEC, RTM_NEWTFILTER, tc_ctl_tfilter, NULL, 0);
	rtnl_register(PF_UNSPEC, RTM_DELTFILTER, tc_ctl_tfilter, NULL, 0);
1235
	rtnl_register(PF_UNSPEC, RTM_GETTFILTER, tc_ctl_tfilter,
1236
		      tc_dump_tfilter, 0);
L
Linus Torvalds 已提交
1237 1238 1239 1240 1241

	return 0;
}

subsys_initcall(tc_filter_init);