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v3.1
   1/*
   2 * net/sched/act_api.c	Packet action 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 * Author:	Jamal Hadi Salim
  10 *
  11 *
  12 */
  13
  14#include <linux/types.h>
  15#include <linux/kernel.h>
  16#include <linux/string.h>
  17#include <linux/errno.h>
  18#include <linux/slab.h>
  19#include <linux/skbuff.h>
  20#include <linux/init.h>
  21#include <linux/kmod.h>
  22#include <linux/err.h>
 
  23#include <net/net_namespace.h>
  24#include <net/sock.h>
  25#include <net/sch_generic.h>
  26#include <net/act_api.h>
  27#include <net/netlink.h>
  28
  29void tcf_hash_destroy(struct tcf_common *p, struct tcf_hashinfo *hinfo)
  30{
  31	unsigned int h = tcf_hash(p->tcfc_index, hinfo->hmask);
  32	struct tcf_common **p1p;
  33
  34	for (p1p = &hinfo->htab[h]; *p1p; p1p = &(*p1p)->tcfc_next) {
  35		if (*p1p == p) {
  36			write_lock_bh(hinfo->lock);
  37			*p1p = p->tcfc_next;
  38			write_unlock_bh(hinfo->lock);
  39			gen_kill_estimator(&p->tcfc_bstats,
  40					   &p->tcfc_rate_est);
  41			/*
  42			 * gen_estimator est_timer() might access p->tcfc_lock
  43			 * or bstats, wait a RCU grace period before freeing p
  44			 */
  45			kfree_rcu(p, tcfc_rcu);
  46			return;
  47		}
  48	}
  49	WARN_ON(1);
  50}
  51EXPORT_SYMBOL(tcf_hash_destroy);
  52
  53int tcf_hash_release(struct tcf_common *p, int bind,
  54		     struct tcf_hashinfo *hinfo)
  55{
  56	int ret = 0;
  57
  58	if (p) {
  59		if (bind)
  60			p->tcfc_bindcnt--;
  61
  62		p->tcfc_refcnt--;
  63		if (p->tcfc_bindcnt <= 0 && p->tcfc_refcnt <= 0) {
  64			tcf_hash_destroy(p, hinfo);
  65			ret = 1;
  66		}
  67	}
  68	return ret;
  69}
  70EXPORT_SYMBOL(tcf_hash_release);
  71
  72static int tcf_dump_walker(struct sk_buff *skb, struct netlink_callback *cb,
  73			   struct tc_action *a, struct tcf_hashinfo *hinfo)
  74{
  75	struct tcf_common *p;
  76	int err = 0, index = -1, i = 0, s_i = 0, n_i = 0;
  77	struct nlattr *nest;
  78
  79	read_lock_bh(hinfo->lock);
  80
  81	s_i = cb->args[0];
  82
  83	for (i = 0; i < (hinfo->hmask + 1); i++) {
  84		p = hinfo->htab[tcf_hash(i, hinfo->hmask)];
  85
  86		for (; p; p = p->tcfc_next) {
  87			index++;
  88			if (index < s_i)
  89				continue;
  90			a->priv = p;
  91			a->order = n_i;
  92
  93			nest = nla_nest_start(skb, a->order);
  94			if (nest == NULL)
  95				goto nla_put_failure;
  96			err = tcf_action_dump_1(skb, a, 0, 0);
  97			if (err < 0) {
  98				index--;
  99				nlmsg_trim(skb, nest);
 100				goto done;
 101			}
 102			nla_nest_end(skb, nest);
 103			n_i++;
 104			if (n_i >= TCA_ACT_MAX_PRIO)
 105				goto done;
 106		}
 107	}
 108done:
 109	read_unlock_bh(hinfo->lock);
 110	if (n_i)
 111		cb->args[0] += n_i;
 112	return n_i;
 113
 114nla_put_failure:
 115	nla_nest_cancel(skb, nest);
 116	goto done;
 117}
 118
 119static int tcf_del_walker(struct sk_buff *skb, struct tc_action *a,
 120			  struct tcf_hashinfo *hinfo)
 121{
 122	struct tcf_common *p, *s_p;
 123	struct nlattr *nest;
 124	int i = 0, n_i = 0;
 125
 126	nest = nla_nest_start(skb, a->order);
 127	if (nest == NULL)
 128		goto nla_put_failure;
 129	NLA_PUT_STRING(skb, TCA_KIND, a->ops->kind);
 
 130	for (i = 0; i < (hinfo->hmask + 1); i++) {
 131		p = hinfo->htab[tcf_hash(i, hinfo->hmask)];
 132
 133		while (p != NULL) {
 134			s_p = p->tcfc_next;
 135			if (ACT_P_DELETED == tcf_hash_release(p, 0, hinfo))
 136				module_put(a->ops->owner);
 137			n_i++;
 138			p = s_p;
 139		}
 140	}
 141	NLA_PUT_U32(skb, TCA_FCNT, n_i);
 
 142	nla_nest_end(skb, nest);
 143
 144	return n_i;
 145nla_put_failure:
 146	nla_nest_cancel(skb, nest);
 147	return -EINVAL;
 148}
 149
 150int tcf_generic_walker(struct sk_buff *skb, struct netlink_callback *cb,
 151		       int type, struct tc_action *a)
 152{
 153	struct tcf_hashinfo *hinfo = a->ops->hinfo;
 154
 155	if (type == RTM_DELACTION) {
 156		return tcf_del_walker(skb, a, hinfo);
 157	} else if (type == RTM_GETACTION) {
 158		return tcf_dump_walker(skb, cb, a, hinfo);
 159	} else {
 160		WARN(1, "tcf_generic_walker: unknown action %d\n", type);
 161		return -EINVAL;
 162	}
 163}
 164EXPORT_SYMBOL(tcf_generic_walker);
 165
 166struct tcf_common *tcf_hash_lookup(u32 index, struct tcf_hashinfo *hinfo)
 167{
 168	struct tcf_common *p;
 169
 170	read_lock_bh(hinfo->lock);
 171	for (p = hinfo->htab[tcf_hash(index, hinfo->hmask)]; p;
 172	     p = p->tcfc_next) {
 173		if (p->tcfc_index == index)
 174			break;
 175	}
 176	read_unlock_bh(hinfo->lock);
 177
 178	return p;
 179}
 180EXPORT_SYMBOL(tcf_hash_lookup);
 181
 182u32 tcf_hash_new_index(u32 *idx_gen, struct tcf_hashinfo *hinfo)
 183{
 184	u32 val = *idx_gen;
 185
 186	do {
 187		if (++val == 0)
 188			val = 1;
 189	} while (tcf_hash_lookup(val, hinfo));
 190
 191	return (*idx_gen = val);
 192}
 193EXPORT_SYMBOL(tcf_hash_new_index);
 194
 195int tcf_hash_search(struct tc_action *a, u32 index)
 196{
 197	struct tcf_hashinfo *hinfo = a->ops->hinfo;
 198	struct tcf_common *p = tcf_hash_lookup(index, hinfo);
 199
 200	if (p) {
 201		a->priv = p;
 202		return 1;
 203	}
 204	return 0;
 205}
 206EXPORT_SYMBOL(tcf_hash_search);
 207
 208struct tcf_common *tcf_hash_check(u32 index, struct tc_action *a, int bind,
 209				  struct tcf_hashinfo *hinfo)
 210{
 211	struct tcf_common *p = NULL;
 212	if (index && (p = tcf_hash_lookup(index, hinfo)) != NULL) {
 213		if (bind)
 214			p->tcfc_bindcnt++;
 215		p->tcfc_refcnt++;
 216		a->priv = p;
 217	}
 218	return p;
 219}
 220EXPORT_SYMBOL(tcf_hash_check);
 221
 222struct tcf_common *tcf_hash_create(u32 index, struct nlattr *est,
 223				   struct tc_action *a, int size, int bind,
 224				   u32 *idx_gen, struct tcf_hashinfo *hinfo)
 225{
 226	struct tcf_common *p = kzalloc(size, GFP_KERNEL);
 227
 228	if (unlikely(!p))
 229		return ERR_PTR(-ENOMEM);
 230	p->tcfc_refcnt = 1;
 231	if (bind)
 232		p->tcfc_bindcnt = 1;
 233
 234	spin_lock_init(&p->tcfc_lock);
 235	p->tcfc_index = index ? index : tcf_hash_new_index(idx_gen, hinfo);
 236	p->tcfc_tm.install = jiffies;
 237	p->tcfc_tm.lastuse = jiffies;
 238	if (est) {
 239		int err = gen_new_estimator(&p->tcfc_bstats, &p->tcfc_rate_est,
 240					    &p->tcfc_lock, est);
 241		if (err) {
 242			kfree(p);
 243			return ERR_PTR(err);
 244		}
 245	}
 246
 247	a->priv = (void *) p;
 248	return p;
 249}
 250EXPORT_SYMBOL(tcf_hash_create);
 251
 252void tcf_hash_insert(struct tcf_common *p, struct tcf_hashinfo *hinfo)
 253{
 254	unsigned int h = tcf_hash(p->tcfc_index, hinfo->hmask);
 255
 256	write_lock_bh(hinfo->lock);
 257	p->tcfc_next = hinfo->htab[h];
 258	hinfo->htab[h] = p;
 259	write_unlock_bh(hinfo->lock);
 260}
 261EXPORT_SYMBOL(tcf_hash_insert);
 262
 263static struct tc_action_ops *act_base = NULL;
 264static DEFINE_RWLOCK(act_mod_lock);
 265
 266int tcf_register_action(struct tc_action_ops *act)
 267{
 268	struct tc_action_ops *a, **ap;
 269
 270	write_lock(&act_mod_lock);
 271	for (ap = &act_base; (a = *ap) != NULL; ap = &a->next) {
 272		if (act->type == a->type || (strcmp(act->kind, a->kind) == 0)) {
 273			write_unlock(&act_mod_lock);
 274			return -EEXIST;
 275		}
 276	}
 277	act->next = NULL;
 278	*ap = act;
 279	write_unlock(&act_mod_lock);
 280	return 0;
 281}
 282EXPORT_SYMBOL(tcf_register_action);
 283
 284int tcf_unregister_action(struct tc_action_ops *act)
 285{
 286	struct tc_action_ops *a, **ap;
 287	int err = -ENOENT;
 288
 289	write_lock(&act_mod_lock);
 290	for (ap = &act_base; (a = *ap) != NULL; ap = &a->next)
 291		if (a == act)
 292			break;
 293	if (a) {
 294		*ap = a->next;
 295		a->next = NULL;
 296		err = 0;
 297	}
 298	write_unlock(&act_mod_lock);
 299	return err;
 300}
 301EXPORT_SYMBOL(tcf_unregister_action);
 302
 303/* lookup by name */
 304static struct tc_action_ops *tc_lookup_action_n(char *kind)
 305{
 306	struct tc_action_ops *a = NULL;
 307
 308	if (kind) {
 309		read_lock(&act_mod_lock);
 310		for (a = act_base; a; a = a->next) {
 311			if (strcmp(kind, a->kind) == 0) {
 312				if (!try_module_get(a->owner)) {
 313					read_unlock(&act_mod_lock);
 314					return NULL;
 315				}
 316				break;
 317			}
 318		}
 319		read_unlock(&act_mod_lock);
 320	}
 321	return a;
 322}
 323
 324/* lookup by nlattr */
 325static struct tc_action_ops *tc_lookup_action(struct nlattr *kind)
 326{
 327	struct tc_action_ops *a = NULL;
 328
 329	if (kind) {
 330		read_lock(&act_mod_lock);
 331		for (a = act_base; a; a = a->next) {
 332			if (nla_strcmp(kind, a->kind) == 0) {
 333				if (!try_module_get(a->owner)) {
 334					read_unlock(&act_mod_lock);
 335					return NULL;
 336				}
 337				break;
 338			}
 339		}
 340		read_unlock(&act_mod_lock);
 341	}
 342	return a;
 343}
 344
 345#if 0
 346/* lookup by id */
 347static struct tc_action_ops *tc_lookup_action_id(u32 type)
 348{
 349	struct tc_action_ops *a = NULL;
 350
 351	if (type) {
 352		read_lock(&act_mod_lock);
 353		for (a = act_base; a; a = a->next) {
 354			if (a->type == type) {
 355				if (!try_module_get(a->owner)) {
 356					read_unlock(&act_mod_lock);
 357					return NULL;
 358				}
 359				break;
 360			}
 361		}
 362		read_unlock(&act_mod_lock);
 363	}
 364	return a;
 365}
 366#endif
 367
 368int tcf_action_exec(struct sk_buff *skb, const struct tc_action *act,
 369		    struct tcf_result *res)
 370{
 371	const struct tc_action *a;
 372	int ret = -1;
 373
 374	if (skb->tc_verd & TC_NCLS) {
 375		skb->tc_verd = CLR_TC_NCLS(skb->tc_verd);
 376		ret = TC_ACT_OK;
 377		goto exec_done;
 378	}
 379	while ((a = act) != NULL) {
 380repeat:
 381		if (a->ops && a->ops->act) {
 382			ret = a->ops->act(skb, a, res);
 383			if (TC_MUNGED & skb->tc_verd) {
 384				/* copied already, allow trampling */
 385				skb->tc_verd = SET_TC_OK2MUNGE(skb->tc_verd);
 386				skb->tc_verd = CLR_TC_MUNGED(skb->tc_verd);
 387			}
 388			if (ret == TC_ACT_REPEAT)
 389				goto repeat;	/* we need a ttl - JHS */
 390			if (ret != TC_ACT_PIPE)
 391				goto exec_done;
 392		}
 393		act = a->next;
 394	}
 395exec_done:
 396	return ret;
 397}
 398EXPORT_SYMBOL(tcf_action_exec);
 399
 400void tcf_action_destroy(struct tc_action *act, int bind)
 401{
 402	struct tc_action *a;
 403
 404	for (a = act; a; a = act) {
 405		if (a->ops && a->ops->cleanup) {
 406			if (a->ops->cleanup(a, bind) == ACT_P_DELETED)
 407				module_put(a->ops->owner);
 408			act = act->next;
 409			kfree(a);
 410		} else {
 411			/*FIXME: Remove later - catch insertion bugs*/
 412			WARN(1, "tcf_action_destroy: BUG? destroying NULL ops\n");
 413			act = act->next;
 414			kfree(a);
 415		}
 416	}
 417}
 418
 419int
 420tcf_action_dump_old(struct sk_buff *skb, struct tc_action *a, int bind, int ref)
 421{
 422	int err = -EINVAL;
 423
 424	if (a->ops == NULL || a->ops->dump == NULL)
 425		return err;
 426	return a->ops->dump(skb, a, bind, ref);
 427}
 428
 429int
 430tcf_action_dump_1(struct sk_buff *skb, struct tc_action *a, int bind, int ref)
 431{
 432	int err = -EINVAL;
 433	unsigned char *b = skb_tail_pointer(skb);
 434	struct nlattr *nest;
 435
 436	if (a->ops == NULL || a->ops->dump == NULL)
 437		return err;
 438
 439	NLA_PUT_STRING(skb, TCA_KIND, a->ops->kind);
 
 440	if (tcf_action_copy_stats(skb, a, 0))
 441		goto nla_put_failure;
 442	nest = nla_nest_start(skb, TCA_OPTIONS);
 443	if (nest == NULL)
 444		goto nla_put_failure;
 445	err = tcf_action_dump_old(skb, a, bind, ref);
 446	if (err > 0) {
 447		nla_nest_end(skb, nest);
 448		return err;
 449	}
 450
 451nla_put_failure:
 452	nlmsg_trim(skb, b);
 453	return -1;
 454}
 455EXPORT_SYMBOL(tcf_action_dump_1);
 456
 457int
 458tcf_action_dump(struct sk_buff *skb, struct tc_action *act, int bind, int ref)
 459{
 460	struct tc_action *a;
 461	int err = -EINVAL;
 462	struct nlattr *nest;
 463
 464	while ((a = act) != NULL) {
 465		act = a->next;
 466		nest = nla_nest_start(skb, a->order);
 467		if (nest == NULL)
 468			goto nla_put_failure;
 469		err = tcf_action_dump_1(skb, a, bind, ref);
 470		if (err < 0)
 471			goto errout;
 472		nla_nest_end(skb, nest);
 473	}
 474
 475	return 0;
 476
 477nla_put_failure:
 478	err = -EINVAL;
 479errout:
 480	nla_nest_cancel(skb, nest);
 481	return err;
 482}
 483
 484struct tc_action *tcf_action_init_1(struct nlattr *nla, struct nlattr *est,
 485				    char *name, int ovr, int bind)
 486{
 487	struct tc_action *a;
 488	struct tc_action_ops *a_o;
 489	char act_name[IFNAMSIZ];
 490	struct nlattr *tb[TCA_ACT_MAX + 1];
 491	struct nlattr *kind;
 492	int err;
 493
 494	if (name == NULL) {
 495		err = nla_parse_nested(tb, TCA_ACT_MAX, nla, NULL);
 496		if (err < 0)
 497			goto err_out;
 498		err = -EINVAL;
 499		kind = tb[TCA_ACT_KIND];
 500		if (kind == NULL)
 501			goto err_out;
 502		if (nla_strlcpy(act_name, kind, IFNAMSIZ) >= IFNAMSIZ)
 503			goto err_out;
 504	} else {
 505		err = -EINVAL;
 506		if (strlcpy(act_name, name, IFNAMSIZ) >= IFNAMSIZ)
 507			goto err_out;
 508	}
 509
 510	a_o = tc_lookup_action_n(act_name);
 511	if (a_o == NULL) {
 512#ifdef CONFIG_MODULES
 513		rtnl_unlock();
 514		request_module("act_%s", act_name);
 515		rtnl_lock();
 516
 517		a_o = tc_lookup_action_n(act_name);
 518
 519		/* We dropped the RTNL semaphore in order to
 520		 * perform the module load.  So, even if we
 521		 * succeeded in loading the module we have to
 522		 * tell the caller to replay the request.  We
 523		 * indicate this using -EAGAIN.
 524		 */
 525		if (a_o != NULL) {
 526			err = -EAGAIN;
 527			goto err_mod;
 528		}
 529#endif
 530		err = -ENOENT;
 531		goto err_out;
 532	}
 533
 534	err = -ENOMEM;
 535	a = kzalloc(sizeof(*a), GFP_KERNEL);
 536	if (a == NULL)
 537		goto err_mod;
 538
 539	/* backward compatibility for policer */
 540	if (name == NULL)
 541		err = a_o->init(tb[TCA_ACT_OPTIONS], est, a, ovr, bind);
 542	else
 543		err = a_o->init(nla, est, a, ovr, bind);
 544	if (err < 0)
 545		goto err_free;
 546
 547	/* module count goes up only when brand new policy is created
 548	 * if it exists and is only bound to in a_o->init() then
 549	 * ACT_P_CREATED is not returned (a zero is).
 550	 */
 551	if (err != ACT_P_CREATED)
 552		module_put(a_o->owner);
 553	a->ops = a_o;
 554
 555	return a;
 556
 557err_free:
 558	kfree(a);
 559err_mod:
 560	module_put(a_o->owner);
 561err_out:
 562	return ERR_PTR(err);
 563}
 564
 565struct tc_action *tcf_action_init(struct nlattr *nla, struct nlattr *est,
 566				  char *name, int ovr, int bind)
 567{
 568	struct nlattr *tb[TCA_ACT_MAX_PRIO + 1];
 569	struct tc_action *head = NULL, *act, *act_prev = NULL;
 570	int err;
 571	int i;
 572
 573	err = nla_parse_nested(tb, TCA_ACT_MAX_PRIO, nla, NULL);
 574	if (err < 0)
 575		return ERR_PTR(err);
 576
 577	for (i = 1; i <= TCA_ACT_MAX_PRIO && tb[i]; i++) {
 578		act = tcf_action_init_1(tb[i], est, name, ovr, bind);
 579		if (IS_ERR(act))
 580			goto err;
 581		act->order = i;
 582
 583		if (head == NULL)
 584			head = act;
 585		else
 586			act_prev->next = act;
 587		act_prev = act;
 588	}
 589	return head;
 590
 591err:
 592	if (head != NULL)
 593		tcf_action_destroy(head, bind);
 594	return act;
 595}
 596
 597int tcf_action_copy_stats(struct sk_buff *skb, struct tc_action *a,
 598			  int compat_mode)
 599{
 600	int err = 0;
 601	struct gnet_dump d;
 602	struct tcf_act_hdr *h = a->priv;
 603
 604	if (h == NULL)
 605		goto errout;
 606
 607	/* compat_mode being true specifies a call that is supposed
 608	 * to add additional backward compatibility statistic TLVs.
 609	 */
 610	if (compat_mode) {
 611		if (a->type == TCA_OLD_COMPAT)
 612			err = gnet_stats_start_copy_compat(skb, 0,
 613				TCA_STATS, TCA_XSTATS, &h->tcf_lock, &d);
 614		else
 615			return 0;
 616	} else
 617		err = gnet_stats_start_copy(skb, TCA_ACT_STATS,
 618					    &h->tcf_lock, &d);
 619
 620	if (err < 0)
 621		goto errout;
 622
 623	if (a->ops != NULL && a->ops->get_stats != NULL)
 624		if (a->ops->get_stats(skb, a) < 0)
 625			goto errout;
 626
 627	if (gnet_stats_copy_basic(&d, &h->tcf_bstats) < 0 ||
 628	    gnet_stats_copy_rate_est(&d, &h->tcf_bstats,
 629				     &h->tcf_rate_est) < 0 ||
 630	    gnet_stats_copy_queue(&d, &h->tcf_qstats) < 0)
 631		goto errout;
 632
 633	if (gnet_stats_finish_copy(&d) < 0)
 634		goto errout;
 635
 636	return 0;
 637
 638errout:
 639	return -1;
 640}
 641
 642static int
 643tca_get_fill(struct sk_buff *skb, struct tc_action *a, u32 pid, u32 seq,
 644	     u16 flags, int event, int bind, int ref)
 645{
 646	struct tcamsg *t;
 647	struct nlmsghdr *nlh;
 648	unsigned char *b = skb_tail_pointer(skb);
 649	struct nlattr *nest;
 650
 651	nlh = NLMSG_NEW(skb, pid, seq, event, sizeof(*t), flags);
 652
 653	t = NLMSG_DATA(nlh);
 654	t->tca_family = AF_UNSPEC;
 655	t->tca__pad1 = 0;
 656	t->tca__pad2 = 0;
 657
 658	nest = nla_nest_start(skb, TCA_ACT_TAB);
 659	if (nest == NULL)
 660		goto nla_put_failure;
 661
 662	if (tcf_action_dump(skb, a, bind, ref) < 0)
 663		goto nla_put_failure;
 664
 665	nla_nest_end(skb, nest);
 666
 667	nlh->nlmsg_len = skb_tail_pointer(skb) - b;
 668	return skb->len;
 669
 670nla_put_failure:
 671nlmsg_failure:
 672	nlmsg_trim(skb, b);
 673	return -1;
 674}
 675
 676static int
 677act_get_notify(struct net *net, u32 pid, struct nlmsghdr *n,
 678	       struct tc_action *a, int event)
 679{
 680	struct sk_buff *skb;
 681
 682	skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
 683	if (!skb)
 684		return -ENOBUFS;
 685	if (tca_get_fill(skb, a, pid, n->nlmsg_seq, 0, event, 0, 0) <= 0) {
 686		kfree_skb(skb);
 687		return -EINVAL;
 688	}
 689
 690	return rtnl_unicast(skb, net, pid);
 691}
 692
 693static struct tc_action *
 694tcf_action_get_1(struct nlattr *nla, struct nlmsghdr *n, u32 pid)
 695{
 696	struct nlattr *tb[TCA_ACT_MAX + 1];
 697	struct tc_action *a;
 698	int index;
 699	int err;
 700
 701	err = nla_parse_nested(tb, TCA_ACT_MAX, nla, NULL);
 702	if (err < 0)
 703		goto err_out;
 704
 705	err = -EINVAL;
 706	if (tb[TCA_ACT_INDEX] == NULL ||
 707	    nla_len(tb[TCA_ACT_INDEX]) < sizeof(index))
 708		goto err_out;
 709	index = nla_get_u32(tb[TCA_ACT_INDEX]);
 710
 711	err = -ENOMEM;
 712	a = kzalloc(sizeof(struct tc_action), GFP_KERNEL);
 713	if (a == NULL)
 714		goto err_out;
 715
 716	err = -EINVAL;
 717	a->ops = tc_lookup_action(tb[TCA_ACT_KIND]);
 718	if (a->ops == NULL)
 719		goto err_free;
 720	if (a->ops->lookup == NULL)
 721		goto err_mod;
 722	err = -ENOENT;
 723	if (a->ops->lookup(a, index) == 0)
 724		goto err_mod;
 725
 726	module_put(a->ops->owner);
 727	return a;
 728
 729err_mod:
 730	module_put(a->ops->owner);
 731err_free:
 732	kfree(a);
 733err_out:
 734	return ERR_PTR(err);
 735}
 736
 737static void cleanup_a(struct tc_action *act)
 738{
 739	struct tc_action *a;
 740
 741	for (a = act; a; a = act) {
 742		act = a->next;
 743		kfree(a);
 744	}
 745}
 746
 747static struct tc_action *create_a(int i)
 748{
 749	struct tc_action *act;
 750
 751	act = kzalloc(sizeof(*act), GFP_KERNEL);
 752	if (act == NULL) {
 753		pr_debug("create_a: failed to alloc!\n");
 754		return NULL;
 755	}
 756	act->order = i;
 757	return act;
 758}
 759
 760static int tca_action_flush(struct net *net, struct nlattr *nla,
 761			    struct nlmsghdr *n, u32 pid)
 762{
 763	struct sk_buff *skb;
 764	unsigned char *b;
 765	struct nlmsghdr *nlh;
 766	struct tcamsg *t;
 767	struct netlink_callback dcb;
 768	struct nlattr *nest;
 769	struct nlattr *tb[TCA_ACT_MAX + 1];
 770	struct nlattr *kind;
 771	struct tc_action *a = create_a(0);
 772	int err = -ENOMEM;
 773
 774	if (a == NULL) {
 775		pr_debug("tca_action_flush: couldnt create tc_action\n");
 776		return err;
 777	}
 778
 779	skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
 780	if (!skb) {
 781		pr_debug("tca_action_flush: failed skb alloc\n");
 782		kfree(a);
 783		return err;
 784	}
 785
 786	b = skb_tail_pointer(skb);
 787
 788	err = nla_parse_nested(tb, TCA_ACT_MAX, nla, NULL);
 789	if (err < 0)
 790		goto err_out;
 791
 792	err = -EINVAL;
 793	kind = tb[TCA_ACT_KIND];
 794	a->ops = tc_lookup_action(kind);
 795	if (a->ops == NULL)
 796		goto err_out;
 797
 798	nlh = NLMSG_PUT(skb, pid, n->nlmsg_seq, RTM_DELACTION, sizeof(*t));
 799	t = NLMSG_DATA(nlh);
 800	t->tca_family = AF_UNSPEC;
 801	t->tca__pad1 = 0;
 802	t->tca__pad2 = 0;
 803
 804	nest = nla_nest_start(skb, TCA_ACT_TAB);
 805	if (nest == NULL)
 806		goto nla_put_failure;
 807
 808	err = a->ops->walk(skb, &dcb, RTM_DELACTION, a);
 809	if (err < 0)
 810		goto nla_put_failure;
 811	if (err == 0)
 812		goto noflush_out;
 813
 814	nla_nest_end(skb, nest);
 815
 816	nlh->nlmsg_len = skb_tail_pointer(skb) - b;
 817	nlh->nlmsg_flags |= NLM_F_ROOT;
 818	module_put(a->ops->owner);
 819	kfree(a);
 820	err = rtnetlink_send(skb, net, pid, RTNLGRP_TC,
 821			     n->nlmsg_flags & NLM_F_ECHO);
 822	if (err > 0)
 823		return 0;
 824
 825	return err;
 826
 827nla_put_failure:
 828nlmsg_failure:
 829	module_put(a->ops->owner);
 830err_out:
 831noflush_out:
 832	kfree_skb(skb);
 833	kfree(a);
 834	return err;
 835}
 836
 837static int
 838tca_action_gd(struct net *net, struct nlattr *nla, struct nlmsghdr *n,
 839	      u32 pid, int event)
 840{
 841	int i, ret;
 842	struct nlattr *tb[TCA_ACT_MAX_PRIO + 1];
 843	struct tc_action *head = NULL, *act, *act_prev = NULL;
 844
 845	ret = nla_parse_nested(tb, TCA_ACT_MAX_PRIO, nla, NULL);
 846	if (ret < 0)
 847		return ret;
 848
 849	if (event == RTM_DELACTION && n->nlmsg_flags & NLM_F_ROOT) {
 850		if (tb[1] != NULL)
 851			return tca_action_flush(net, tb[1], n, pid);
 852		else
 853			return -EINVAL;
 854	}
 855
 856	for (i = 1; i <= TCA_ACT_MAX_PRIO && tb[i]; i++) {
 857		act = tcf_action_get_1(tb[i], n, pid);
 858		if (IS_ERR(act)) {
 859			ret = PTR_ERR(act);
 860			goto err;
 861		}
 862		act->order = i;
 863
 864		if (head == NULL)
 865			head = act;
 866		else
 867			act_prev->next = act;
 868		act_prev = act;
 869	}
 870
 871	if (event == RTM_GETACTION)
 872		ret = act_get_notify(net, pid, n, head, event);
 873	else { /* delete */
 874		struct sk_buff *skb;
 875
 876		skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
 877		if (!skb) {
 878			ret = -ENOBUFS;
 879			goto err;
 880		}
 881
 882		if (tca_get_fill(skb, head, pid, n->nlmsg_seq, 0, event,
 883				 0, 1) <= 0) {
 884			kfree_skb(skb);
 885			ret = -EINVAL;
 886			goto err;
 887		}
 888
 889		/* now do the delete */
 890		tcf_action_destroy(head, 0);
 891		ret = rtnetlink_send(skb, net, pid, RTNLGRP_TC,
 892				     n->nlmsg_flags & NLM_F_ECHO);
 893		if (ret > 0)
 894			return 0;
 895		return ret;
 896	}
 897err:
 898	cleanup_a(head);
 899	return ret;
 900}
 901
 902static int tcf_add_notify(struct net *net, struct tc_action *a,
 903			  u32 pid, u32 seq, int event, u16 flags)
 904{
 905	struct tcamsg *t;
 906	struct nlmsghdr *nlh;
 907	struct sk_buff *skb;
 908	struct nlattr *nest;
 909	unsigned char *b;
 910	int err = 0;
 911
 912	skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
 913	if (!skb)
 914		return -ENOBUFS;
 915
 916	b = skb_tail_pointer(skb);
 917
 918	nlh = NLMSG_NEW(skb, pid, seq, event, sizeof(*t), flags);
 919	t = NLMSG_DATA(nlh);
 920	t->tca_family = AF_UNSPEC;
 921	t->tca__pad1 = 0;
 922	t->tca__pad2 = 0;
 923
 924	nest = nla_nest_start(skb, TCA_ACT_TAB);
 925	if (nest == NULL)
 926		goto nla_put_failure;
 927
 928	if (tcf_action_dump(skb, a, 0, 0) < 0)
 929		goto nla_put_failure;
 930
 931	nla_nest_end(skb, nest);
 932
 933	nlh->nlmsg_len = skb_tail_pointer(skb) - b;
 934	NETLINK_CB(skb).dst_group = RTNLGRP_TC;
 935
 936	err = rtnetlink_send(skb, net, pid, RTNLGRP_TC, flags & NLM_F_ECHO);
 937	if (err > 0)
 938		err = 0;
 939	return err;
 940
 941nla_put_failure:
 942nlmsg_failure:
 943	kfree_skb(skb);
 944	return -1;
 945}
 946
 947
 948static int
 949tcf_action_add(struct net *net, struct nlattr *nla, struct nlmsghdr *n,
 950	       u32 pid, int ovr)
 951{
 952	int ret = 0;
 953	struct tc_action *act;
 954	struct tc_action *a;
 955	u32 seq = n->nlmsg_seq;
 956
 957	act = tcf_action_init(nla, NULL, NULL, ovr, 0);
 958	if (act == NULL)
 959		goto done;
 960	if (IS_ERR(act)) {
 961		ret = PTR_ERR(act);
 962		goto done;
 963	}
 964
 965	/* dump then free all the actions after update; inserted policy
 966	 * stays intact
 967	 */
 968	ret = tcf_add_notify(net, act, pid, seq, RTM_NEWACTION, n->nlmsg_flags);
 969	for (a = act; a; a = act) {
 970		act = a->next;
 971		kfree(a);
 972	}
 973done:
 974	return ret;
 975}
 976
 977static int tc_ctl_action(struct sk_buff *skb, struct nlmsghdr *n, void *arg)
 978{
 979	struct net *net = sock_net(skb->sk);
 980	struct nlattr *tca[TCA_ACT_MAX + 1];
 981	u32 pid = skb ? NETLINK_CB(skb).pid : 0;
 982	int ret = 0, ovr = 0;
 983
 984	ret = nlmsg_parse(n, sizeof(struct tcamsg), tca, TCA_ACT_MAX, NULL);
 985	if (ret < 0)
 986		return ret;
 987
 988	if (tca[TCA_ACT_TAB] == NULL) {
 989		pr_notice("tc_ctl_action: received NO action attribs\n");
 990		return -EINVAL;
 991	}
 992
 993	/* n->nlmsg_flags & NLM_F_CREATE */
 994	switch (n->nlmsg_type) {
 995	case RTM_NEWACTION:
 996		/* we are going to assume all other flags
 997		 * imply create only if it doesn't exist
 998		 * Note that CREATE | EXCL implies that
 999		 * but since we want avoid ambiguity (eg when flags
1000		 * is zero) then just set this
1001		 */
1002		if (n->nlmsg_flags & NLM_F_REPLACE)
1003			ovr = 1;
1004replay:
1005		ret = tcf_action_add(net, tca[TCA_ACT_TAB], n, pid, ovr);
1006		if (ret == -EAGAIN)
1007			goto replay;
1008		break;
1009	case RTM_DELACTION:
1010		ret = tca_action_gd(net, tca[TCA_ACT_TAB], n,
1011				    pid, RTM_DELACTION);
1012		break;
1013	case RTM_GETACTION:
1014		ret = tca_action_gd(net, tca[TCA_ACT_TAB], n,
1015				    pid, RTM_GETACTION);
1016		break;
1017	default:
1018		BUG();
1019	}
1020
1021	return ret;
1022}
1023
1024static struct nlattr *
1025find_dump_kind(const struct nlmsghdr *n)
1026{
1027	struct nlattr *tb1, *tb2[TCA_ACT_MAX + 1];
1028	struct nlattr *tb[TCA_ACT_MAX_PRIO + 1];
1029	struct nlattr *nla[TCAA_MAX + 1];
1030	struct nlattr *kind;
1031
1032	if (nlmsg_parse(n, sizeof(struct tcamsg), nla, TCAA_MAX, NULL) < 0)
1033		return NULL;
1034	tb1 = nla[TCA_ACT_TAB];
1035	if (tb1 == NULL)
1036		return NULL;
1037
1038	if (nla_parse(tb, TCA_ACT_MAX_PRIO, nla_data(tb1),
1039		      NLMSG_ALIGN(nla_len(tb1)), NULL) < 0)
1040		return NULL;
1041
1042	if (tb[1] == NULL)
1043		return NULL;
1044	if (nla_parse(tb2, TCA_ACT_MAX, nla_data(tb[1]),
1045		      nla_len(tb[1]), NULL) < 0)
1046		return NULL;
1047	kind = tb2[TCA_ACT_KIND];
1048
1049	return kind;
1050}
1051
1052static int
1053tc_dump_action(struct sk_buff *skb, struct netlink_callback *cb)
1054{
1055	struct nlmsghdr *nlh;
1056	unsigned char *b = skb_tail_pointer(skb);
1057	struct nlattr *nest;
1058	struct tc_action_ops *a_o;
1059	struct tc_action a;
1060	int ret = 0;
1061	struct tcamsg *t = (struct tcamsg *) NLMSG_DATA(cb->nlh);
1062	struct nlattr *kind = find_dump_kind(cb->nlh);
1063
1064	if (kind == NULL) {
1065		pr_info("tc_dump_action: action bad kind\n");
1066		return 0;
1067	}
1068
1069	a_o = tc_lookup_action(kind);
1070	if (a_o == NULL)
1071		return 0;
1072
1073	memset(&a, 0, sizeof(struct tc_action));
1074	a.ops = a_o;
1075
1076	if (a_o->walk == NULL) {
1077		WARN(1, "tc_dump_action: %s !capable of dumping table\n",
1078		     a_o->kind);
1079		goto nla_put_failure;
1080	}
1081
1082	nlh = NLMSG_PUT(skb, NETLINK_CB(cb->skb).pid, cb->nlh->nlmsg_seq,
1083			cb->nlh->nlmsg_type, sizeof(*t));
1084	t = NLMSG_DATA(nlh);
1085	t->tca_family = AF_UNSPEC;
1086	t->tca__pad1 = 0;
1087	t->tca__pad2 = 0;
1088
1089	nest = nla_nest_start(skb, TCA_ACT_TAB);
1090	if (nest == NULL)
1091		goto nla_put_failure;
1092
1093	ret = a_o->walk(skb, cb, RTM_GETACTION, &a);
1094	if (ret < 0)
1095		goto nla_put_failure;
1096
1097	if (ret > 0) {
1098		nla_nest_end(skb, nest);
1099		ret = skb->len;
1100	} else
1101		nla_nest_cancel(skb, nest);
1102
1103	nlh->nlmsg_len = skb_tail_pointer(skb) - b;
1104	if (NETLINK_CB(cb->skb).pid && ret)
1105		nlh->nlmsg_flags |= NLM_F_MULTI;
1106	module_put(a_o->owner);
1107	return skb->len;
1108
1109nla_put_failure:
1110nlmsg_failure:
1111	module_put(a_o->owner);
1112	nlmsg_trim(skb, b);
1113	return skb->len;
1114}
1115
1116static int __init tc_action_init(void)
1117{
1118	rtnl_register(PF_UNSPEC, RTM_NEWACTION, tc_ctl_action, NULL, NULL);
1119	rtnl_register(PF_UNSPEC, RTM_DELACTION, tc_ctl_action, NULL, NULL);
1120	rtnl_register(PF_UNSPEC, RTM_GETACTION, tc_ctl_action, tc_dump_action,
1121		      NULL);
1122
1123	return 0;
1124}
1125
1126subsys_initcall(tc_action_init);
v3.5.6
   1/*
   2 * net/sched/act_api.c	Packet action 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 * Author:	Jamal Hadi Salim
  10 *
  11 *
  12 */
  13
  14#include <linux/types.h>
  15#include <linux/kernel.h>
  16#include <linux/string.h>
  17#include <linux/errno.h>
  18#include <linux/slab.h>
  19#include <linux/skbuff.h>
  20#include <linux/init.h>
  21#include <linux/kmod.h>
  22#include <linux/err.h>
  23#include <linux/module.h>
  24#include <net/net_namespace.h>
  25#include <net/sock.h>
  26#include <net/sch_generic.h>
  27#include <net/act_api.h>
  28#include <net/netlink.h>
  29
  30void tcf_hash_destroy(struct tcf_common *p, struct tcf_hashinfo *hinfo)
  31{
  32	unsigned int h = tcf_hash(p->tcfc_index, hinfo->hmask);
  33	struct tcf_common **p1p;
  34
  35	for (p1p = &hinfo->htab[h]; *p1p; p1p = &(*p1p)->tcfc_next) {
  36		if (*p1p == p) {
  37			write_lock_bh(hinfo->lock);
  38			*p1p = p->tcfc_next;
  39			write_unlock_bh(hinfo->lock);
  40			gen_kill_estimator(&p->tcfc_bstats,
  41					   &p->tcfc_rate_est);
  42			/*
  43			 * gen_estimator est_timer() might access p->tcfc_lock
  44			 * or bstats, wait a RCU grace period before freeing p
  45			 */
  46			kfree_rcu(p, tcfc_rcu);
  47			return;
  48		}
  49	}
  50	WARN_ON(1);
  51}
  52EXPORT_SYMBOL(tcf_hash_destroy);
  53
  54int tcf_hash_release(struct tcf_common *p, int bind,
  55		     struct tcf_hashinfo *hinfo)
  56{
  57	int ret = 0;
  58
  59	if (p) {
  60		if (bind)
  61			p->tcfc_bindcnt--;
  62
  63		p->tcfc_refcnt--;
  64		if (p->tcfc_bindcnt <= 0 && p->tcfc_refcnt <= 0) {
  65			tcf_hash_destroy(p, hinfo);
  66			ret = 1;
  67		}
  68	}
  69	return ret;
  70}
  71EXPORT_SYMBOL(tcf_hash_release);
  72
  73static int tcf_dump_walker(struct sk_buff *skb, struct netlink_callback *cb,
  74			   struct tc_action *a, struct tcf_hashinfo *hinfo)
  75{
  76	struct tcf_common *p;
  77	int err = 0, index = -1, i = 0, s_i = 0, n_i = 0;
  78	struct nlattr *nest;
  79
  80	read_lock_bh(hinfo->lock);
  81
  82	s_i = cb->args[0];
  83
  84	for (i = 0; i < (hinfo->hmask + 1); i++) {
  85		p = hinfo->htab[tcf_hash(i, hinfo->hmask)];
  86
  87		for (; p; p = p->tcfc_next) {
  88			index++;
  89			if (index < s_i)
  90				continue;
  91			a->priv = p;
  92			a->order = n_i;
  93
  94			nest = nla_nest_start(skb, a->order);
  95			if (nest == NULL)
  96				goto nla_put_failure;
  97			err = tcf_action_dump_1(skb, a, 0, 0);
  98			if (err < 0) {
  99				index--;
 100				nlmsg_trim(skb, nest);
 101				goto done;
 102			}
 103			nla_nest_end(skb, nest);
 104			n_i++;
 105			if (n_i >= TCA_ACT_MAX_PRIO)
 106				goto done;
 107		}
 108	}
 109done:
 110	read_unlock_bh(hinfo->lock);
 111	if (n_i)
 112		cb->args[0] += n_i;
 113	return n_i;
 114
 115nla_put_failure:
 116	nla_nest_cancel(skb, nest);
 117	goto done;
 118}
 119
 120static int tcf_del_walker(struct sk_buff *skb, struct tc_action *a,
 121			  struct tcf_hashinfo *hinfo)
 122{
 123	struct tcf_common *p, *s_p;
 124	struct nlattr *nest;
 125	int i = 0, n_i = 0;
 126
 127	nest = nla_nest_start(skb, a->order);
 128	if (nest == NULL)
 129		goto nla_put_failure;
 130	if (nla_put_string(skb, TCA_KIND, a->ops->kind))
 131		goto nla_put_failure;
 132	for (i = 0; i < (hinfo->hmask + 1); i++) {
 133		p = hinfo->htab[tcf_hash(i, hinfo->hmask)];
 134
 135		while (p != NULL) {
 136			s_p = p->tcfc_next;
 137			if (ACT_P_DELETED == tcf_hash_release(p, 0, hinfo))
 138				module_put(a->ops->owner);
 139			n_i++;
 140			p = s_p;
 141		}
 142	}
 143	if (nla_put_u32(skb, TCA_FCNT, n_i))
 144		goto nla_put_failure;
 145	nla_nest_end(skb, nest);
 146
 147	return n_i;
 148nla_put_failure:
 149	nla_nest_cancel(skb, nest);
 150	return -EINVAL;
 151}
 152
 153int tcf_generic_walker(struct sk_buff *skb, struct netlink_callback *cb,
 154		       int type, struct tc_action *a)
 155{
 156	struct tcf_hashinfo *hinfo = a->ops->hinfo;
 157
 158	if (type == RTM_DELACTION) {
 159		return tcf_del_walker(skb, a, hinfo);
 160	} else if (type == RTM_GETACTION) {
 161		return tcf_dump_walker(skb, cb, a, hinfo);
 162	} else {
 163		WARN(1, "tcf_generic_walker: unknown action %d\n", type);
 164		return -EINVAL;
 165	}
 166}
 167EXPORT_SYMBOL(tcf_generic_walker);
 168
 169struct tcf_common *tcf_hash_lookup(u32 index, struct tcf_hashinfo *hinfo)
 170{
 171	struct tcf_common *p;
 172
 173	read_lock_bh(hinfo->lock);
 174	for (p = hinfo->htab[tcf_hash(index, hinfo->hmask)]; p;
 175	     p = p->tcfc_next) {
 176		if (p->tcfc_index == index)
 177			break;
 178	}
 179	read_unlock_bh(hinfo->lock);
 180
 181	return p;
 182}
 183EXPORT_SYMBOL(tcf_hash_lookup);
 184
 185u32 tcf_hash_new_index(u32 *idx_gen, struct tcf_hashinfo *hinfo)
 186{
 187	u32 val = *idx_gen;
 188
 189	do {
 190		if (++val == 0)
 191			val = 1;
 192	} while (tcf_hash_lookup(val, hinfo));
 193
 194	return (*idx_gen = val);
 195}
 196EXPORT_SYMBOL(tcf_hash_new_index);
 197
 198int tcf_hash_search(struct tc_action *a, u32 index)
 199{
 200	struct tcf_hashinfo *hinfo = a->ops->hinfo;
 201	struct tcf_common *p = tcf_hash_lookup(index, hinfo);
 202
 203	if (p) {
 204		a->priv = p;
 205		return 1;
 206	}
 207	return 0;
 208}
 209EXPORT_SYMBOL(tcf_hash_search);
 210
 211struct tcf_common *tcf_hash_check(u32 index, struct tc_action *a, int bind,
 212				  struct tcf_hashinfo *hinfo)
 213{
 214	struct tcf_common *p = NULL;
 215	if (index && (p = tcf_hash_lookup(index, hinfo)) != NULL) {
 216		if (bind)
 217			p->tcfc_bindcnt++;
 218		p->tcfc_refcnt++;
 219		a->priv = p;
 220	}
 221	return p;
 222}
 223EXPORT_SYMBOL(tcf_hash_check);
 224
 225struct tcf_common *tcf_hash_create(u32 index, struct nlattr *est,
 226				   struct tc_action *a, int size, int bind,
 227				   u32 *idx_gen, struct tcf_hashinfo *hinfo)
 228{
 229	struct tcf_common *p = kzalloc(size, GFP_KERNEL);
 230
 231	if (unlikely(!p))
 232		return ERR_PTR(-ENOMEM);
 233	p->tcfc_refcnt = 1;
 234	if (bind)
 235		p->tcfc_bindcnt = 1;
 236
 237	spin_lock_init(&p->tcfc_lock);
 238	p->tcfc_index = index ? index : tcf_hash_new_index(idx_gen, hinfo);
 239	p->tcfc_tm.install = jiffies;
 240	p->tcfc_tm.lastuse = jiffies;
 241	if (est) {
 242		int err = gen_new_estimator(&p->tcfc_bstats, &p->tcfc_rate_est,
 243					    &p->tcfc_lock, est);
 244		if (err) {
 245			kfree(p);
 246			return ERR_PTR(err);
 247		}
 248	}
 249
 250	a->priv = (void *) p;
 251	return p;
 252}
 253EXPORT_SYMBOL(tcf_hash_create);
 254
 255void tcf_hash_insert(struct tcf_common *p, struct tcf_hashinfo *hinfo)
 256{
 257	unsigned int h = tcf_hash(p->tcfc_index, hinfo->hmask);
 258
 259	write_lock_bh(hinfo->lock);
 260	p->tcfc_next = hinfo->htab[h];
 261	hinfo->htab[h] = p;
 262	write_unlock_bh(hinfo->lock);
 263}
 264EXPORT_SYMBOL(tcf_hash_insert);
 265
 266static struct tc_action_ops *act_base = NULL;
 267static DEFINE_RWLOCK(act_mod_lock);
 268
 269int tcf_register_action(struct tc_action_ops *act)
 270{
 271	struct tc_action_ops *a, **ap;
 272
 273	write_lock(&act_mod_lock);
 274	for (ap = &act_base; (a = *ap) != NULL; ap = &a->next) {
 275		if (act->type == a->type || (strcmp(act->kind, a->kind) == 0)) {
 276			write_unlock(&act_mod_lock);
 277			return -EEXIST;
 278		}
 279	}
 280	act->next = NULL;
 281	*ap = act;
 282	write_unlock(&act_mod_lock);
 283	return 0;
 284}
 285EXPORT_SYMBOL(tcf_register_action);
 286
 287int tcf_unregister_action(struct tc_action_ops *act)
 288{
 289	struct tc_action_ops *a, **ap;
 290	int err = -ENOENT;
 291
 292	write_lock(&act_mod_lock);
 293	for (ap = &act_base; (a = *ap) != NULL; ap = &a->next)
 294		if (a == act)
 295			break;
 296	if (a) {
 297		*ap = a->next;
 298		a->next = NULL;
 299		err = 0;
 300	}
 301	write_unlock(&act_mod_lock);
 302	return err;
 303}
 304EXPORT_SYMBOL(tcf_unregister_action);
 305
 306/* lookup by name */
 307static struct tc_action_ops *tc_lookup_action_n(char *kind)
 308{
 309	struct tc_action_ops *a = NULL;
 310
 311	if (kind) {
 312		read_lock(&act_mod_lock);
 313		for (a = act_base; a; a = a->next) {
 314			if (strcmp(kind, a->kind) == 0) {
 315				if (!try_module_get(a->owner)) {
 316					read_unlock(&act_mod_lock);
 317					return NULL;
 318				}
 319				break;
 320			}
 321		}
 322		read_unlock(&act_mod_lock);
 323	}
 324	return a;
 325}
 326
 327/* lookup by nlattr */
 328static struct tc_action_ops *tc_lookup_action(struct nlattr *kind)
 329{
 330	struct tc_action_ops *a = NULL;
 331
 332	if (kind) {
 333		read_lock(&act_mod_lock);
 334		for (a = act_base; a; a = a->next) {
 335			if (nla_strcmp(kind, a->kind) == 0) {
 336				if (!try_module_get(a->owner)) {
 337					read_unlock(&act_mod_lock);
 338					return NULL;
 339				}
 340				break;
 341			}
 342		}
 343		read_unlock(&act_mod_lock);
 344	}
 345	return a;
 346}
 347
 348#if 0
 349/* lookup by id */
 350static struct tc_action_ops *tc_lookup_action_id(u32 type)
 351{
 352	struct tc_action_ops *a = NULL;
 353
 354	if (type) {
 355		read_lock(&act_mod_lock);
 356		for (a = act_base; a; a = a->next) {
 357			if (a->type == type) {
 358				if (!try_module_get(a->owner)) {
 359					read_unlock(&act_mod_lock);
 360					return NULL;
 361				}
 362				break;
 363			}
 364		}
 365		read_unlock(&act_mod_lock);
 366	}
 367	return a;
 368}
 369#endif
 370
 371int tcf_action_exec(struct sk_buff *skb, const struct tc_action *act,
 372		    struct tcf_result *res)
 373{
 374	const struct tc_action *a;
 375	int ret = -1;
 376
 377	if (skb->tc_verd & TC_NCLS) {
 378		skb->tc_verd = CLR_TC_NCLS(skb->tc_verd);
 379		ret = TC_ACT_OK;
 380		goto exec_done;
 381	}
 382	while ((a = act) != NULL) {
 383repeat:
 384		if (a->ops && a->ops->act) {
 385			ret = a->ops->act(skb, a, res);
 386			if (TC_MUNGED & skb->tc_verd) {
 387				/* copied already, allow trampling */
 388				skb->tc_verd = SET_TC_OK2MUNGE(skb->tc_verd);
 389				skb->tc_verd = CLR_TC_MUNGED(skb->tc_verd);
 390			}
 391			if (ret == TC_ACT_REPEAT)
 392				goto repeat;	/* we need a ttl - JHS */
 393			if (ret != TC_ACT_PIPE)
 394				goto exec_done;
 395		}
 396		act = a->next;
 397	}
 398exec_done:
 399	return ret;
 400}
 401EXPORT_SYMBOL(tcf_action_exec);
 402
 403void tcf_action_destroy(struct tc_action *act, int bind)
 404{
 405	struct tc_action *a;
 406
 407	for (a = act; a; a = act) {
 408		if (a->ops && a->ops->cleanup) {
 409			if (a->ops->cleanup(a, bind) == ACT_P_DELETED)
 410				module_put(a->ops->owner);
 411			act = act->next;
 412			kfree(a);
 413		} else {
 414			/*FIXME: Remove later - catch insertion bugs*/
 415			WARN(1, "tcf_action_destroy: BUG? destroying NULL ops\n");
 416			act = act->next;
 417			kfree(a);
 418		}
 419	}
 420}
 421
 422int
 423tcf_action_dump_old(struct sk_buff *skb, struct tc_action *a, int bind, int ref)
 424{
 425	int err = -EINVAL;
 426
 427	if (a->ops == NULL || a->ops->dump == NULL)
 428		return err;
 429	return a->ops->dump(skb, a, bind, ref);
 430}
 431
 432int
 433tcf_action_dump_1(struct sk_buff *skb, struct tc_action *a, int bind, int ref)
 434{
 435	int err = -EINVAL;
 436	unsigned char *b = skb_tail_pointer(skb);
 437	struct nlattr *nest;
 438
 439	if (a->ops == NULL || a->ops->dump == NULL)
 440		return err;
 441
 442	if (nla_put_string(skb, TCA_KIND, a->ops->kind))
 443		goto nla_put_failure;
 444	if (tcf_action_copy_stats(skb, a, 0))
 445		goto nla_put_failure;
 446	nest = nla_nest_start(skb, TCA_OPTIONS);
 447	if (nest == NULL)
 448		goto nla_put_failure;
 449	err = tcf_action_dump_old(skb, a, bind, ref);
 450	if (err > 0) {
 451		nla_nest_end(skb, nest);
 452		return err;
 453	}
 454
 455nla_put_failure:
 456	nlmsg_trim(skb, b);
 457	return -1;
 458}
 459EXPORT_SYMBOL(tcf_action_dump_1);
 460
 461int
 462tcf_action_dump(struct sk_buff *skb, struct tc_action *act, int bind, int ref)
 463{
 464	struct tc_action *a;
 465	int err = -EINVAL;
 466	struct nlattr *nest;
 467
 468	while ((a = act) != NULL) {
 469		act = a->next;
 470		nest = nla_nest_start(skb, a->order);
 471		if (nest == NULL)
 472			goto nla_put_failure;
 473		err = tcf_action_dump_1(skb, a, bind, ref);
 474		if (err < 0)
 475			goto errout;
 476		nla_nest_end(skb, nest);
 477	}
 478
 479	return 0;
 480
 481nla_put_failure:
 482	err = -EINVAL;
 483errout:
 484	nla_nest_cancel(skb, nest);
 485	return err;
 486}
 487
 488struct tc_action *tcf_action_init_1(struct nlattr *nla, struct nlattr *est,
 489				    char *name, int ovr, int bind)
 490{
 491	struct tc_action *a;
 492	struct tc_action_ops *a_o;
 493	char act_name[IFNAMSIZ];
 494	struct nlattr *tb[TCA_ACT_MAX + 1];
 495	struct nlattr *kind;
 496	int err;
 497
 498	if (name == NULL) {
 499		err = nla_parse_nested(tb, TCA_ACT_MAX, nla, NULL);
 500		if (err < 0)
 501			goto err_out;
 502		err = -EINVAL;
 503		kind = tb[TCA_ACT_KIND];
 504		if (kind == NULL)
 505			goto err_out;
 506		if (nla_strlcpy(act_name, kind, IFNAMSIZ) >= IFNAMSIZ)
 507			goto err_out;
 508	} else {
 509		err = -EINVAL;
 510		if (strlcpy(act_name, name, IFNAMSIZ) >= IFNAMSIZ)
 511			goto err_out;
 512	}
 513
 514	a_o = tc_lookup_action_n(act_name);
 515	if (a_o == NULL) {
 516#ifdef CONFIG_MODULES
 517		rtnl_unlock();
 518		request_module("act_%s", act_name);
 519		rtnl_lock();
 520
 521		a_o = tc_lookup_action_n(act_name);
 522
 523		/* We dropped the RTNL semaphore in order to
 524		 * perform the module load.  So, even if we
 525		 * succeeded in loading the module we have to
 526		 * tell the caller to replay the request.  We
 527		 * indicate this using -EAGAIN.
 528		 */
 529		if (a_o != NULL) {
 530			err = -EAGAIN;
 531			goto err_mod;
 532		}
 533#endif
 534		err = -ENOENT;
 535		goto err_out;
 536	}
 537
 538	err = -ENOMEM;
 539	a = kzalloc(sizeof(*a), GFP_KERNEL);
 540	if (a == NULL)
 541		goto err_mod;
 542
 543	/* backward compatibility for policer */
 544	if (name == NULL)
 545		err = a_o->init(tb[TCA_ACT_OPTIONS], est, a, ovr, bind);
 546	else
 547		err = a_o->init(nla, est, a, ovr, bind);
 548	if (err < 0)
 549		goto err_free;
 550
 551	/* module count goes up only when brand new policy is created
 552	 * if it exists and is only bound to in a_o->init() then
 553	 * ACT_P_CREATED is not returned (a zero is).
 554	 */
 555	if (err != ACT_P_CREATED)
 556		module_put(a_o->owner);
 557	a->ops = a_o;
 558
 559	return a;
 560
 561err_free:
 562	kfree(a);
 563err_mod:
 564	module_put(a_o->owner);
 565err_out:
 566	return ERR_PTR(err);
 567}
 568
 569struct tc_action *tcf_action_init(struct nlattr *nla, struct nlattr *est,
 570				  char *name, int ovr, int bind)
 571{
 572	struct nlattr *tb[TCA_ACT_MAX_PRIO + 1];
 573	struct tc_action *head = NULL, *act, *act_prev = NULL;
 574	int err;
 575	int i;
 576
 577	err = nla_parse_nested(tb, TCA_ACT_MAX_PRIO, nla, NULL);
 578	if (err < 0)
 579		return ERR_PTR(err);
 580
 581	for (i = 1; i <= TCA_ACT_MAX_PRIO && tb[i]; i++) {
 582		act = tcf_action_init_1(tb[i], est, name, ovr, bind);
 583		if (IS_ERR(act))
 584			goto err;
 585		act->order = i;
 586
 587		if (head == NULL)
 588			head = act;
 589		else
 590			act_prev->next = act;
 591		act_prev = act;
 592	}
 593	return head;
 594
 595err:
 596	if (head != NULL)
 597		tcf_action_destroy(head, bind);
 598	return act;
 599}
 600
 601int tcf_action_copy_stats(struct sk_buff *skb, struct tc_action *a,
 602			  int compat_mode)
 603{
 604	int err = 0;
 605	struct gnet_dump d;
 606	struct tcf_act_hdr *h = a->priv;
 607
 608	if (h == NULL)
 609		goto errout;
 610
 611	/* compat_mode being true specifies a call that is supposed
 612	 * to add additional backward compatibility statistic TLVs.
 613	 */
 614	if (compat_mode) {
 615		if (a->type == TCA_OLD_COMPAT)
 616			err = gnet_stats_start_copy_compat(skb, 0,
 617				TCA_STATS, TCA_XSTATS, &h->tcf_lock, &d);
 618		else
 619			return 0;
 620	} else
 621		err = gnet_stats_start_copy(skb, TCA_ACT_STATS,
 622					    &h->tcf_lock, &d);
 623
 624	if (err < 0)
 625		goto errout;
 626
 627	if (a->ops != NULL && a->ops->get_stats != NULL)
 628		if (a->ops->get_stats(skb, a) < 0)
 629			goto errout;
 630
 631	if (gnet_stats_copy_basic(&d, &h->tcf_bstats) < 0 ||
 632	    gnet_stats_copy_rate_est(&d, &h->tcf_bstats,
 633				     &h->tcf_rate_est) < 0 ||
 634	    gnet_stats_copy_queue(&d, &h->tcf_qstats) < 0)
 635		goto errout;
 636
 637	if (gnet_stats_finish_copy(&d) < 0)
 638		goto errout;
 639
 640	return 0;
 641
 642errout:
 643	return -1;
 644}
 645
 646static int
 647tca_get_fill(struct sk_buff *skb, struct tc_action *a, u32 pid, u32 seq,
 648	     u16 flags, int event, int bind, int ref)
 649{
 650	struct tcamsg *t;
 651	struct nlmsghdr *nlh;
 652	unsigned char *b = skb_tail_pointer(skb);
 653	struct nlattr *nest;
 654
 655	nlh = NLMSG_NEW(skb, pid, seq, event, sizeof(*t), flags);
 656
 657	t = NLMSG_DATA(nlh);
 658	t->tca_family = AF_UNSPEC;
 659	t->tca__pad1 = 0;
 660	t->tca__pad2 = 0;
 661
 662	nest = nla_nest_start(skb, TCA_ACT_TAB);
 663	if (nest == NULL)
 664		goto nla_put_failure;
 665
 666	if (tcf_action_dump(skb, a, bind, ref) < 0)
 667		goto nla_put_failure;
 668
 669	nla_nest_end(skb, nest);
 670
 671	nlh->nlmsg_len = skb_tail_pointer(skb) - b;
 672	return skb->len;
 673
 674nla_put_failure:
 675nlmsg_failure:
 676	nlmsg_trim(skb, b);
 677	return -1;
 678}
 679
 680static int
 681act_get_notify(struct net *net, u32 pid, struct nlmsghdr *n,
 682	       struct tc_action *a, int event)
 683{
 684	struct sk_buff *skb;
 685
 686	skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
 687	if (!skb)
 688		return -ENOBUFS;
 689	if (tca_get_fill(skb, a, pid, n->nlmsg_seq, 0, event, 0, 0) <= 0) {
 690		kfree_skb(skb);
 691		return -EINVAL;
 692	}
 693
 694	return rtnl_unicast(skb, net, pid);
 695}
 696
 697static struct tc_action *
 698tcf_action_get_1(struct nlattr *nla, struct nlmsghdr *n, u32 pid)
 699{
 700	struct nlattr *tb[TCA_ACT_MAX + 1];
 701	struct tc_action *a;
 702	int index;
 703	int err;
 704
 705	err = nla_parse_nested(tb, TCA_ACT_MAX, nla, NULL);
 706	if (err < 0)
 707		goto err_out;
 708
 709	err = -EINVAL;
 710	if (tb[TCA_ACT_INDEX] == NULL ||
 711	    nla_len(tb[TCA_ACT_INDEX]) < sizeof(index))
 712		goto err_out;
 713	index = nla_get_u32(tb[TCA_ACT_INDEX]);
 714
 715	err = -ENOMEM;
 716	a = kzalloc(sizeof(struct tc_action), GFP_KERNEL);
 717	if (a == NULL)
 718		goto err_out;
 719
 720	err = -EINVAL;
 721	a->ops = tc_lookup_action(tb[TCA_ACT_KIND]);
 722	if (a->ops == NULL)
 723		goto err_free;
 724	if (a->ops->lookup == NULL)
 725		goto err_mod;
 726	err = -ENOENT;
 727	if (a->ops->lookup(a, index) == 0)
 728		goto err_mod;
 729
 730	module_put(a->ops->owner);
 731	return a;
 732
 733err_mod:
 734	module_put(a->ops->owner);
 735err_free:
 736	kfree(a);
 737err_out:
 738	return ERR_PTR(err);
 739}
 740
 741static void cleanup_a(struct tc_action *act)
 742{
 743	struct tc_action *a;
 744
 745	for (a = act; a; a = act) {
 746		act = a->next;
 747		kfree(a);
 748	}
 749}
 750
 751static struct tc_action *create_a(int i)
 752{
 753	struct tc_action *act;
 754
 755	act = kzalloc(sizeof(*act), GFP_KERNEL);
 756	if (act == NULL) {
 757		pr_debug("create_a: failed to alloc!\n");
 758		return NULL;
 759	}
 760	act->order = i;
 761	return act;
 762}
 763
 764static int tca_action_flush(struct net *net, struct nlattr *nla,
 765			    struct nlmsghdr *n, u32 pid)
 766{
 767	struct sk_buff *skb;
 768	unsigned char *b;
 769	struct nlmsghdr *nlh;
 770	struct tcamsg *t;
 771	struct netlink_callback dcb;
 772	struct nlattr *nest;
 773	struct nlattr *tb[TCA_ACT_MAX + 1];
 774	struct nlattr *kind;
 775	struct tc_action *a = create_a(0);
 776	int err = -ENOMEM;
 777
 778	if (a == NULL) {
 779		pr_debug("tca_action_flush: couldnt create tc_action\n");
 780		return err;
 781	}
 782
 783	skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
 784	if (!skb) {
 785		pr_debug("tca_action_flush: failed skb alloc\n");
 786		kfree(a);
 787		return err;
 788	}
 789
 790	b = skb_tail_pointer(skb);
 791
 792	err = nla_parse_nested(tb, TCA_ACT_MAX, nla, NULL);
 793	if (err < 0)
 794		goto err_out;
 795
 796	err = -EINVAL;
 797	kind = tb[TCA_ACT_KIND];
 798	a->ops = tc_lookup_action(kind);
 799	if (a->ops == NULL)
 800		goto err_out;
 801
 802	nlh = NLMSG_PUT(skb, pid, n->nlmsg_seq, RTM_DELACTION, sizeof(*t));
 803	t = NLMSG_DATA(nlh);
 804	t->tca_family = AF_UNSPEC;
 805	t->tca__pad1 = 0;
 806	t->tca__pad2 = 0;
 807
 808	nest = nla_nest_start(skb, TCA_ACT_TAB);
 809	if (nest == NULL)
 810		goto nla_put_failure;
 811
 812	err = a->ops->walk(skb, &dcb, RTM_DELACTION, a);
 813	if (err < 0)
 814		goto nla_put_failure;
 815	if (err == 0)
 816		goto noflush_out;
 817
 818	nla_nest_end(skb, nest);
 819
 820	nlh->nlmsg_len = skb_tail_pointer(skb) - b;
 821	nlh->nlmsg_flags |= NLM_F_ROOT;
 822	module_put(a->ops->owner);
 823	kfree(a);
 824	err = rtnetlink_send(skb, net, pid, RTNLGRP_TC,
 825			     n->nlmsg_flags & NLM_F_ECHO);
 826	if (err > 0)
 827		return 0;
 828
 829	return err;
 830
 831nla_put_failure:
 832nlmsg_failure:
 833	module_put(a->ops->owner);
 834err_out:
 835noflush_out:
 836	kfree_skb(skb);
 837	kfree(a);
 838	return err;
 839}
 840
 841static int
 842tca_action_gd(struct net *net, struct nlattr *nla, struct nlmsghdr *n,
 843	      u32 pid, int event)
 844{
 845	int i, ret;
 846	struct nlattr *tb[TCA_ACT_MAX_PRIO + 1];
 847	struct tc_action *head = NULL, *act, *act_prev = NULL;
 848
 849	ret = nla_parse_nested(tb, TCA_ACT_MAX_PRIO, nla, NULL);
 850	if (ret < 0)
 851		return ret;
 852
 853	if (event == RTM_DELACTION && n->nlmsg_flags & NLM_F_ROOT) {
 854		if (tb[1] != NULL)
 855			return tca_action_flush(net, tb[1], n, pid);
 856		else
 857			return -EINVAL;
 858	}
 859
 860	for (i = 1; i <= TCA_ACT_MAX_PRIO && tb[i]; i++) {
 861		act = tcf_action_get_1(tb[i], n, pid);
 862		if (IS_ERR(act)) {
 863			ret = PTR_ERR(act);
 864			goto err;
 865		}
 866		act->order = i;
 867
 868		if (head == NULL)
 869			head = act;
 870		else
 871			act_prev->next = act;
 872		act_prev = act;
 873	}
 874
 875	if (event == RTM_GETACTION)
 876		ret = act_get_notify(net, pid, n, head, event);
 877	else { /* delete */
 878		struct sk_buff *skb;
 879
 880		skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
 881		if (!skb) {
 882			ret = -ENOBUFS;
 883			goto err;
 884		}
 885
 886		if (tca_get_fill(skb, head, pid, n->nlmsg_seq, 0, event,
 887				 0, 1) <= 0) {
 888			kfree_skb(skb);
 889			ret = -EINVAL;
 890			goto err;
 891		}
 892
 893		/* now do the delete */
 894		tcf_action_destroy(head, 0);
 895		ret = rtnetlink_send(skb, net, pid, RTNLGRP_TC,
 896				     n->nlmsg_flags & NLM_F_ECHO);
 897		if (ret > 0)
 898			return 0;
 899		return ret;
 900	}
 901err:
 902	cleanup_a(head);
 903	return ret;
 904}
 905
 906static int tcf_add_notify(struct net *net, struct tc_action *a,
 907			  u32 pid, u32 seq, int event, u16 flags)
 908{
 909	struct tcamsg *t;
 910	struct nlmsghdr *nlh;
 911	struct sk_buff *skb;
 912	struct nlattr *nest;
 913	unsigned char *b;
 914	int err = 0;
 915
 916	skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
 917	if (!skb)
 918		return -ENOBUFS;
 919
 920	b = skb_tail_pointer(skb);
 921
 922	nlh = NLMSG_NEW(skb, pid, seq, event, sizeof(*t), flags);
 923	t = NLMSG_DATA(nlh);
 924	t->tca_family = AF_UNSPEC;
 925	t->tca__pad1 = 0;
 926	t->tca__pad2 = 0;
 927
 928	nest = nla_nest_start(skb, TCA_ACT_TAB);
 929	if (nest == NULL)
 930		goto nla_put_failure;
 931
 932	if (tcf_action_dump(skb, a, 0, 0) < 0)
 933		goto nla_put_failure;
 934
 935	nla_nest_end(skb, nest);
 936
 937	nlh->nlmsg_len = skb_tail_pointer(skb) - b;
 938	NETLINK_CB(skb).dst_group = RTNLGRP_TC;
 939
 940	err = rtnetlink_send(skb, net, pid, RTNLGRP_TC, flags & NLM_F_ECHO);
 941	if (err > 0)
 942		err = 0;
 943	return err;
 944
 945nla_put_failure:
 946nlmsg_failure:
 947	kfree_skb(skb);
 948	return -1;
 949}
 950
 951
 952static int
 953tcf_action_add(struct net *net, struct nlattr *nla, struct nlmsghdr *n,
 954	       u32 pid, int ovr)
 955{
 956	int ret = 0;
 957	struct tc_action *act;
 958	struct tc_action *a;
 959	u32 seq = n->nlmsg_seq;
 960
 961	act = tcf_action_init(nla, NULL, NULL, ovr, 0);
 962	if (act == NULL)
 963		goto done;
 964	if (IS_ERR(act)) {
 965		ret = PTR_ERR(act);
 966		goto done;
 967	}
 968
 969	/* dump then free all the actions after update; inserted policy
 970	 * stays intact
 971	 */
 972	ret = tcf_add_notify(net, act, pid, seq, RTM_NEWACTION, n->nlmsg_flags);
 973	for (a = act; a; a = act) {
 974		act = a->next;
 975		kfree(a);
 976	}
 977done:
 978	return ret;
 979}
 980
 981static int tc_ctl_action(struct sk_buff *skb, struct nlmsghdr *n, void *arg)
 982{
 983	struct net *net = sock_net(skb->sk);
 984	struct nlattr *tca[TCA_ACT_MAX + 1];
 985	u32 pid = skb ? NETLINK_CB(skb).pid : 0;
 986	int ret = 0, ovr = 0;
 987
 988	ret = nlmsg_parse(n, sizeof(struct tcamsg), tca, TCA_ACT_MAX, NULL);
 989	if (ret < 0)
 990		return ret;
 991
 992	if (tca[TCA_ACT_TAB] == NULL) {
 993		pr_notice("tc_ctl_action: received NO action attribs\n");
 994		return -EINVAL;
 995	}
 996
 997	/* n->nlmsg_flags & NLM_F_CREATE */
 998	switch (n->nlmsg_type) {
 999	case RTM_NEWACTION:
1000		/* we are going to assume all other flags
1001		 * imply create only if it doesn't exist
1002		 * Note that CREATE | EXCL implies that
1003		 * but since we want avoid ambiguity (eg when flags
1004		 * is zero) then just set this
1005		 */
1006		if (n->nlmsg_flags & NLM_F_REPLACE)
1007			ovr = 1;
1008replay:
1009		ret = tcf_action_add(net, tca[TCA_ACT_TAB], n, pid, ovr);
1010		if (ret == -EAGAIN)
1011			goto replay;
1012		break;
1013	case RTM_DELACTION:
1014		ret = tca_action_gd(net, tca[TCA_ACT_TAB], n,
1015				    pid, RTM_DELACTION);
1016		break;
1017	case RTM_GETACTION:
1018		ret = tca_action_gd(net, tca[TCA_ACT_TAB], n,
1019				    pid, RTM_GETACTION);
1020		break;
1021	default:
1022		BUG();
1023	}
1024
1025	return ret;
1026}
1027
1028static struct nlattr *
1029find_dump_kind(const struct nlmsghdr *n)
1030{
1031	struct nlattr *tb1, *tb2[TCA_ACT_MAX + 1];
1032	struct nlattr *tb[TCA_ACT_MAX_PRIO + 1];
1033	struct nlattr *nla[TCAA_MAX + 1];
1034	struct nlattr *kind;
1035
1036	if (nlmsg_parse(n, sizeof(struct tcamsg), nla, TCAA_MAX, NULL) < 0)
1037		return NULL;
1038	tb1 = nla[TCA_ACT_TAB];
1039	if (tb1 == NULL)
1040		return NULL;
1041
1042	if (nla_parse(tb, TCA_ACT_MAX_PRIO, nla_data(tb1),
1043		      NLMSG_ALIGN(nla_len(tb1)), NULL) < 0)
1044		return NULL;
1045
1046	if (tb[1] == NULL)
1047		return NULL;
1048	if (nla_parse(tb2, TCA_ACT_MAX, nla_data(tb[1]),
1049		      nla_len(tb[1]), NULL) < 0)
1050		return NULL;
1051	kind = tb2[TCA_ACT_KIND];
1052
1053	return kind;
1054}
1055
1056static int
1057tc_dump_action(struct sk_buff *skb, struct netlink_callback *cb)
1058{
1059	struct nlmsghdr *nlh;
1060	unsigned char *b = skb_tail_pointer(skb);
1061	struct nlattr *nest;
1062	struct tc_action_ops *a_o;
1063	struct tc_action a;
1064	int ret = 0;
1065	struct tcamsg *t = (struct tcamsg *) NLMSG_DATA(cb->nlh);
1066	struct nlattr *kind = find_dump_kind(cb->nlh);
1067
1068	if (kind == NULL) {
1069		pr_info("tc_dump_action: action bad kind\n");
1070		return 0;
1071	}
1072
1073	a_o = tc_lookup_action(kind);
1074	if (a_o == NULL)
1075		return 0;
1076
1077	memset(&a, 0, sizeof(struct tc_action));
1078	a.ops = a_o;
1079
1080	if (a_o->walk == NULL) {
1081		WARN(1, "tc_dump_action: %s !capable of dumping table\n",
1082		     a_o->kind);
1083		goto nla_put_failure;
1084	}
1085
1086	nlh = NLMSG_PUT(skb, NETLINK_CB(cb->skb).pid, cb->nlh->nlmsg_seq,
1087			cb->nlh->nlmsg_type, sizeof(*t));
1088	t = NLMSG_DATA(nlh);
1089	t->tca_family = AF_UNSPEC;
1090	t->tca__pad1 = 0;
1091	t->tca__pad2 = 0;
1092
1093	nest = nla_nest_start(skb, TCA_ACT_TAB);
1094	if (nest == NULL)
1095		goto nla_put_failure;
1096
1097	ret = a_o->walk(skb, cb, RTM_GETACTION, &a);
1098	if (ret < 0)
1099		goto nla_put_failure;
1100
1101	if (ret > 0) {
1102		nla_nest_end(skb, nest);
1103		ret = skb->len;
1104	} else
1105		nla_nest_cancel(skb, nest);
1106
1107	nlh->nlmsg_len = skb_tail_pointer(skb) - b;
1108	if (NETLINK_CB(cb->skb).pid && ret)
1109		nlh->nlmsg_flags |= NLM_F_MULTI;
1110	module_put(a_o->owner);
1111	return skb->len;
1112
1113nla_put_failure:
1114nlmsg_failure:
1115	module_put(a_o->owner);
1116	nlmsg_trim(skb, b);
1117	return skb->len;
1118}
1119
1120static int __init tc_action_init(void)
1121{
1122	rtnl_register(PF_UNSPEC, RTM_NEWACTION, tc_ctl_action, NULL, NULL);
1123	rtnl_register(PF_UNSPEC, RTM_DELACTION, tc_ctl_action, NULL, NULL);
1124	rtnl_register(PF_UNSPEC, RTM_GETACTION, tc_ctl_action, tc_dump_action,
1125		      NULL);
1126
1127	return 0;
1128}
1129
1130subsys_initcall(tc_action_init);