[mirror_ubuntu-bionic-kernel.git] / net / sched / cls_basic.c

/*
 * net/sched/cls_basic.c	Basic Packet Classifier.
 *
 *		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:	Thomas Graf <tgraf@suug.ch>
 */

#include <linux/module.h>
#include <linux/slab.h>
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/string.h>
#include <linux/errno.h>
#include <linux/rtnetlink.h>
#include <linux/skbuff.h>
#include <linux/idr.h>
#include <net/netlink.h>
#include <net/act_api.h>
#include <net/pkt_cls.h>

struct basic_head {
	struct list_head	flist;
	struct idr		handle_idr;
	struct rcu_head		rcu;
};

struct basic_filter {
	u32			handle;
	struct tcf_exts		exts;
	struct tcf_ematch_tree	ematches;
	struct tcf_result	res;
	struct tcf_proto	*tp;
	struct list_head	link;
	union {
		struct work_struct	work;
		struct rcu_head		rcu;
	};
};

static int basic_classify(struct sk_buff *skb, const struct tcf_proto *tp,
			  struct tcf_result *res)
{
	int r;
	struct basic_head *head = rcu_dereference_bh(tp->root);
	struct basic_filter *f;

	list_for_each_entry_rcu(f, &head->flist, link) {
		if (!tcf_em_tree_match(skb, &f->ematches, NULL))
			continue;
		*res = f->res;
		r = tcf_exts_exec(skb, &f->exts, res);
		if (r < 0)
			continue;
		return r;
	}
	return -1;
}

static void *basic_get(struct tcf_proto *tp, u32 handle)
{
	struct basic_head *head = rtnl_dereference(tp->root);
	struct basic_filter *f;

	list_for_each_entry(f, &head->flist, link) {
		if (f->handle == handle) {
			return f;
		}
	}

	return NULL;
}

static int basic_init(struct tcf_proto *tp)
{
	struct basic_head *head;

	head = kzalloc(sizeof(*head), GFP_KERNEL);
	if (head == NULL)
		return -ENOBUFS;
	INIT_LIST_HEAD(&head->flist);
	idr_init(&head->handle_idr);
	rcu_assign_pointer(tp->root, head);
	return 0;
}

static void __basic_delete_filter(struct basic_filter *f)
{
	tcf_exts_destroy(&f->exts);
	tcf_em_tree_destroy(&f->ematches);
	tcf_exts_put_net(&f->exts);
	kfree(f);
}

static void basic_delete_filter_work(struct work_struct *work)
{
	struct basic_filter *f = container_of(work, struct basic_filter, work);

	rtnl_lock();
	__basic_delete_filter(f);
	rtnl_unlock();
}

static void basic_delete_filter(struct rcu_head *head)
{
	struct basic_filter *f = container_of(head, struct basic_filter, rcu);

	INIT_WORK(&f->work, basic_delete_filter_work);
	tcf_queue_work(&f->work);
}

static void basic_destroy(struct tcf_proto *tp)
{
	struct basic_head *head = rtnl_dereference(tp->root);
	struct basic_filter *f, *n;

	list_for_each_entry_safe(f, n, &head->flist, link) {
		list_del_rcu(&f->link);
		tcf_unbind_filter(tp, &f->res);
		idr_remove_ext(&head->handle_idr, f->handle);
		if (tcf_exts_get_net(&f->exts))
			call_rcu(&f->rcu, basic_delete_filter);
		else
			__basic_delete_filter(f);
	}
	idr_destroy(&head->handle_idr);
	kfree_rcu(head, rcu);
}

static int basic_delete(struct tcf_proto *tp, void *arg, bool *last)
{
	struct basic_head *head = rtnl_dereference(tp->root);
	struct basic_filter *f = arg;

	list_del_rcu(&f->link);
	tcf_unbind_filter(tp, &f->res);
	idr_remove_ext(&head->handle_idr, f->handle);
	tcf_exts_get_net(&f->exts);
	call_rcu(&f->rcu, basic_delete_filter);
	*last = list_empty(&head->flist);
	return 0;
}

static const struct nla_policy basic_policy[TCA_BASIC_MAX + 1] = {
	[TCA_BASIC_CLASSID]	= { .type = NLA_U32 },
	[TCA_BASIC_EMATCHES]	= { .type = NLA_NESTED },
};

static int basic_set_parms(struct net *net, struct tcf_proto *tp,
			   struct basic_filter *f, unsigned long base,
			   struct nlattr **tb,
			   struct nlattr *est, bool ovr)
{
	int err;

	err = tcf_exts_validate(net, tp, tb, est, &f->exts, ovr);
	if (err < 0)
		return err;

	err = tcf_em_tree_validate(tp, tb[TCA_BASIC_EMATCHES], &f->ematches);
	if (err < 0)
		return err;

	if (tb[TCA_BASIC_CLASSID]) {
		f->res.classid = nla_get_u32(tb[TCA_BASIC_CLASSID]);
		tcf_bind_filter(tp, &f->res, base);
	}

	f->tp = tp;
	return 0;
}

static int basic_change(struct net *net, struct sk_buff *in_skb,
			struct tcf_proto *tp, unsigned long base, u32 handle,
			struct nlattr **tca, void **arg, bool ovr)
{
	int err;
	struct basic_head *head = rtnl_dereference(tp->root);
	struct nlattr *tb[TCA_BASIC_MAX + 1];
	struct basic_filter *fold = (struct basic_filter *) *arg;
	struct basic_filter *fnew;
	unsigned long idr_index;

	if (tca[TCA_OPTIONS] == NULL)
		return -EINVAL;

	err = nla_parse_nested(tb, TCA_BASIC_MAX, tca[TCA_OPTIONS],
			       basic_policy, NULL);
	if (err < 0)
		return err;

	if (fold != NULL) {
		if (handle && fold->handle != handle)
			return -EINVAL;
	}

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

	err = tcf_exts_init(&fnew->exts, TCA_BASIC_ACT, TCA_BASIC_POLICE);
	if (err < 0)
		goto errout;

	if (handle) {
		fnew->handle = handle;
		if (!fold) {
			err = idr_alloc_ext(&head->handle_idr, fnew, &idr_index,
					    handle, handle + 1, GFP_KERNEL);
			if (err)
				goto errout;
		}
	} else {
		err = idr_alloc_ext(&head->handle_idr, fnew, &idr_index,
				    1, 0x7FFFFFFF, GFP_KERNEL);
		if (err)
			goto errout;
		fnew->handle = idr_index;
	}

	err = basic_set_parms(net, tp, fnew, base, tb, tca[TCA_RATE], ovr);
	if (err < 0) {
		if (!fold)
			idr_remove_ext(&head->handle_idr, fnew->handle);
		goto errout;
	}

	*arg = fnew;

	if (fold) {
		idr_replace_ext(&head->handle_idr, fnew, fnew->handle);
		list_replace_rcu(&fold->link, &fnew->link);
		tcf_unbind_filter(tp, &fold->res);
		tcf_exts_get_net(&fold->exts);
		call_rcu(&fold->rcu, basic_delete_filter);
	} else {
		list_add_rcu(&fnew->link, &head->flist);
	}

	return 0;
errout:
	tcf_exts_destroy(&fnew->exts);
	kfree(fnew);
	return err;
}

static void basic_walk(struct tcf_proto *tp, struct tcf_walker *arg)
{
	struct basic_head *head = rtnl_dereference(tp->root);
	struct basic_filter *f;

	list_for_each_entry(f, &head->flist, link) {
		if (arg->count < arg->skip)
			goto skip;

		if (arg->fn(tp, f, arg) < 0) {
			arg->stop = 1;
			break;
		}
skip:
		arg->count++;
	}
}

static void basic_bind_class(void *fh, u32 classid, unsigned long cl)
{
	struct basic_filter *f = fh;

	if (f && f->res.classid == classid)
		f->res.class = cl;
}

static int basic_dump(struct net *net, struct tcf_proto *tp, void *fh,
		      struct sk_buff *skb, struct tcmsg *t)
{
	struct basic_filter *f = fh;
	struct nlattr *nest;

	if (f == NULL)
		return skb->len;

	t->tcm_handle = f->handle;

	nest = nla_nest_start(skb, TCA_OPTIONS);
	if (nest == NULL)
		goto nla_put_failure;

	if (f->res.classid &&
	    nla_put_u32(skb, TCA_BASIC_CLASSID, f->res.classid))
		goto nla_put_failure;

	if (tcf_exts_dump(skb, &f->exts) < 0 ||
	    tcf_em_tree_dump(skb, &f->ematches, TCA_BASIC_EMATCHES) < 0)
		goto nla_put_failure;

	nla_nest_end(skb, nest);

	if (tcf_exts_dump_stats(skb, &f->exts) < 0)
		goto nla_put_failure;

	return skb->len;

nla_put_failure:
	nla_nest_cancel(skb, nest);
	return -1;
}

static struct tcf_proto_ops cls_basic_ops __read_mostly = {
	.kind		=	"basic",
	.classify	=	basic_classify,
	.init		=	basic_init,
	.destroy	=	basic_destroy,
	.get		=	basic_get,
	.change		=	basic_change,
	.delete		=	basic_delete,
	.walk		=	basic_walk,
	.dump		=	basic_dump,
	.bind_class	=	basic_bind_class,
	.owner		=	THIS_MODULE,
};

static int __init init_basic(void)
{
	return register_tcf_proto_ops(&cls_basic_ops);
}

static void __exit exit_basic(void)
{
	unregister_tcf_proto_ops(&cls_basic_ops);
}

module_init(init_basic)
module_exit(exit_basic)
MODULE_LICENSE("GPL");
Commit	Line	Data
1da177e4 LT	1	/*
	2	* net/sched/cls_basic.c Basic Packet Classifier.
	3	*
	4	* This program is free software; you can redistribute it and/or
	5	* modify it under the terms of the GNU General Public License
	6	* as published by the Free Software Foundation; either version
	7	* 2 of the License, or (at your option) any later version.
	8	*
	9	* Authors: Thomas Graf <tgraf@suug.ch>
	10	*/
	11
1da177e4	12	#include <linux/module.h>
5a0e3ad6	13	#include <linux/slab.h>
1da177e4 LT	14	#include <linux/types.h>
1da177e4 LT	15	#include <linux/kernel.h>
1da177e4	16	#include <linux/string.h>
1da177e4 LT	17	#include <linux/errno.h>
	18	#include <linux/rtnetlink.h>
	19	#include <linux/skbuff.h>
1d8134fe	20	#include <linux/idr.h>
dc5fc579	21	#include <net/netlink.h>
1da177e4 LT	22	#include <net/act_api.h>
	23	#include <net/pkt_cls.h>
	24
cc7ec456	25	struct basic_head {
1da177e4	26	struct list_head flist;
1d8134fe	27	struct idr handle_idr;
9888faef	28	struct rcu_head rcu;
1da177e4 LT	29	};
1da177e4 LT	30
cc7ec456	31	struct basic_filter {
1da177e4 LT	32	u32 handle;
	33	struct tcf_exts exts;
	34	struct tcf_ematch_tree ematches;
	35	struct tcf_result res;
9888faef	36	struct tcf_proto *tp;
1da177e4	37	struct list_head link;
c96a4838 CW	38	union {
	39	struct work_struct work;
	40	struct rcu_head rcu;
	41	};
1da177e4 LT	42	};
1da177e4 LT	43
dc7f9f6e	44	static int basic_classify(struct sk_buff skb, const struct tcf_proto tp,
1da177e4 LT	45	struct tcf_result *res)
	46	{
	47	int r;
9888faef	48	struct basic_head *head = rcu_dereference_bh(tp->root);
1da177e4 LT	49	struct basic_filter *f;
1da177e4 LT	50
9888faef	51	list_for_each_entry_rcu(f, &head->flist, link) {
1da177e4 LT	52	if (!tcf_em_tree_match(skb, &f->ematches, NULL))
	53	continue;
	54	*res = f->res;
	55	r = tcf_exts_exec(skb, &f->exts, res);
	56	if (r < 0)
	57	continue;
	58	return r;
	59	}
	60	return -1;
	61	}
	62
8113c095	63	static void basic_get(struct tcf_proto tp, u32 handle)
1da177e4	64	{
9888faef	65	struct basic_head *head = rtnl_dereference(tp->root);
1da177e4 LT	66	struct basic_filter *f;
1da177e4 LT	67
1c1bc6bd DB	68	list_for_each_entry(f, &head->flist, link) {
1c1bc6bd DB	69	if (f->handle == handle) {
8113c095	70	return f;
1c1bc6bd DB	71	}
1c1bc6bd DB	72	}
1da177e4	73
8113c095	74	return NULL;
1da177e4 LT	75	}
1da177e4 LT	76
1da177e4 LT	77	static int basic_init(struct tcf_proto *tp)
1da177e4 LT	78	{
d3fa76ee PM	79	struct basic_head *head;
	80
	81	head = kzalloc(sizeof(*head), GFP_KERNEL);
	82	if (head == NULL)
	83	return -ENOBUFS;
	84	INIT_LIST_HEAD(&head->flist);
1d8134fe	85	idr_init(&head->handle_idr);
9888faef	86	rcu_assign_pointer(tp->root, head);
1da177e4 LT	87	return 0;
	88	}
	89
0b2a5989 CW	90	static void __basic_delete_filter(struct basic_filter *f)
	91	{
	92	tcf_exts_destroy(&f->exts);
	93	tcf_em_tree_destroy(&f->ematches);
	94	tcf_exts_put_net(&f->exts);
	95	kfree(f);
	96	}
	97
c96a4838	98	static void basic_delete_filter_work(struct work_struct *work)
1da177e4	99	{
c96a4838	100	struct basic_filter *f = container_of(work, struct basic_filter, work);
9888faef	101
c96a4838	102	rtnl_lock();
0b2a5989	103	__basic_delete_filter(f);
c96a4838	104	rtnl_unlock();
1da177e4 LT	105	}
1da177e4 LT	106
c96a4838 CW	107	static void basic_delete_filter(struct rcu_head *head)
	108	{
	109	struct basic_filter *f = container_of(head, struct basic_filter, rcu);
	110
	111	INIT_WORK(&f->work, basic_delete_filter_work);
	112	tcf_queue_work(&f->work);
	113	}
	114
763dbf63	115	static void basic_destroy(struct tcf_proto *tp)
1da177e4	116	{
9888faef	117	struct basic_head *head = rtnl_dereference(tp->root);
1da177e4	118	struct basic_filter f, n;
10297b99	119
1da177e4	120	list_for_each_entry_safe(f, n, &head->flist, link) {
9888faef	121	list_del_rcu(&f->link);
18cdb37e	122	tcf_unbind_filter(tp, &f->res);
1d8134fe	123	idr_remove_ext(&head->handle_idr, f->handle);
0b2a5989 CW	124	if (tcf_exts_get_net(&f->exts))
	125	call_rcu(&f->rcu, basic_delete_filter);
	126	else
	127	__basic_delete_filter(f);
1da177e4	128	}
1d8134fe	129	idr_destroy(&head->handle_idr);
9888faef	130	kfree_rcu(head, rcu);
1da177e4 LT	131	}
1da177e4 LT	132
8113c095	133	static int basic_delete(struct tcf_proto tp, void arg, bool *last)
1da177e4	134	{
763dbf63	135	struct basic_head *head = rtnl_dereference(tp->root);
8113c095	136	struct basic_filter *f = arg;
1da177e4	137
e4386456 JP	138	list_del_rcu(&f->link);
e4386456 JP	139	tcf_unbind_filter(tp, &f->res);
1d8134fe	140	idr_remove_ext(&head->handle_idr, f->handle);
0b2a5989	141	tcf_exts_get_net(&f->exts);
e4386456	142	call_rcu(&f->rcu, basic_delete_filter);
763dbf63	143	*last = list_empty(&head->flist);
e4386456	144	return 0;
1da177e4 LT	145	}
1da177e4 LT	146
6fa8c014 PM	147	static const struct nla_policy basic_policy[TCA_BASIC_MAX + 1] = {
	148	[TCA_BASIC_CLASSID] = { .type = NLA_U32 },
	149	[TCA_BASIC_EMATCHES] = { .type = NLA_NESTED },
	150	};
	151
c1b52739 BL	152	static int basic_set_parms(struct net net, struct tcf_proto tp,
	153	struct basic_filter *f, unsigned long base,
	154	struct nlattr **tb,
2f7ef2f8	155	struct nlattr *est, bool ovr)
1da177e4	156	{
6459082a	157	int err;
1da177e4	158
ff1f8ca0	159	err = tcf_exts_validate(net, tp, tb, est, &f->exts, ovr);
1da177e4 LT	160	if (err < 0)
	161	return err;
	162
4ebc1e3c	163	err = tcf_em_tree_validate(tp, tb[TCA_BASIC_EMATCHES], &f->ematches);
1da177e4	164	if (err < 0)
ff1f8ca0	165	return err;
1da177e4	166
add93b61	167	if (tb[TCA_BASIC_CLASSID]) {
1587bac4	168	f->res.classid = nla_get_u32(tb[TCA_BASIC_CLASSID]);
1da177e4 LT	169	tcf_bind_filter(tp, &f->res, base);
	170	}
	171
9888faef	172	f->tp = tp;
1da177e4	173	return 0;
1da177e4 LT	174	}
1da177e4 LT	175
c1b52739	176	static int basic_change(struct net net, struct sk_buff in_skb,
af4c6641	177	struct tcf_proto *tp, unsigned long base, u32 handle,
8113c095	178	struct nlattr tca, void arg, bool ovr)
1da177e4	179	{
cee63723	180	int err;
9888faef	181	struct basic_head *head = rtnl_dereference(tp->root);
add93b61	182	struct nlattr *tb[TCA_BASIC_MAX + 1];
9888faef JF	183	struct basic_filter fold = (struct basic_filter ) *arg;
9888faef JF	184	struct basic_filter *fnew;
1d8134fe	185	unsigned long idr_index;
1da177e4	186
add93b61	187	if (tca[TCA_OPTIONS] == NULL)
1da177e4 LT	188	return -EINVAL;
1da177e4 LT	189
6fa8c014	190	err = nla_parse_nested(tb, TCA_BASIC_MAX, tca[TCA_OPTIONS],
fceb6435	191	basic_policy, NULL);
cee63723 PM	192	if (err < 0)
cee63723 PM	193	return err;
1da177e4	194
9888faef JF	195	if (fold != NULL) {
9888faef JF	196	if (handle && fold->handle != handle)
1da177e4	197	return -EINVAL;
1da177e4 LT	198	}
1da177e4 LT	199
9888faef	200	fnew = kzalloc(sizeof(*fnew), GFP_KERNEL);
bd42b788 JP	201	if (!fnew)
bd42b788 JP	202	return -ENOBUFS;
1da177e4	203
b9a24bb7 WC	204	err = tcf_exts_init(&fnew->exts, TCA_BASIC_ACT, TCA_BASIC_POLICE);
	205	if (err < 0)
	206	goto errout;
	207
9888faef JF	208	if (handle) {
9888faef JF	209	fnew->handle = handle;
1d8134fe CW	210	if (!fold) {
	211	err = idr_alloc_ext(&head->handle_idr, fnew, &idr_index,
	212	handle, handle + 1, GFP_KERNEL);
	213	if (err)
	214	goto errout;
	215	}
9888faef	216	} else {
1d8134fe CW	217	err = idr_alloc_ext(&head->handle_idr, fnew, &idr_index,
	218	1, 0x7FFFFFFF, GFP_KERNEL);
	219	if (err)
1da177e4	220	goto errout;
1d8134fe	221	fnew->handle = idr_index;
1da177e4 LT	222	}
1da177e4 LT	223
9888faef	224	err = basic_set_parms(net, tp, fnew, base, tb, tca[TCA_RATE], ovr);
1d8134fe CW	225	if (err < 0) {
	226	if (!fold)
	227	idr_remove_ext(&head->handle_idr, fnew->handle);
1da177e4	228	goto errout;
1d8134fe	229	}
1da177e4	230
8113c095	231	*arg = fnew;
9888faef JF	232
9888faef JF	233	if (fold) {
1d8134fe	234	idr_replace_ext(&head->handle_idr, fnew, fnew->handle);
9888faef	235	list_replace_rcu(&fold->link, &fnew->link);
18cdb37e	236	tcf_unbind_filter(tp, &fold->res);
0b2a5989	237	tcf_exts_get_net(&fold->exts);
9888faef JF	238	call_rcu(&fold->rcu, basic_delete_filter);
	239	} else {
	240	list_add_rcu(&fnew->link, &head->flist);
	241	}
1da177e4 LT	242
	243	return 0;
	244	errout:
b9a24bb7	245	tcf_exts_destroy(&fnew->exts);
9888faef	246	kfree(fnew);
1da177e4 LT	247	return err;
	248	}
	249
	250	static void basic_walk(struct tcf_proto tp, struct tcf_walker arg)
	251	{
9888faef	252	struct basic_head *head = rtnl_dereference(tp->root);
1da177e4 LT	253	struct basic_filter *f;
	254
	255	list_for_each_entry(f, &head->flist, link) {
	256	if (arg->count < arg->skip)
	257	goto skip;
	258
8113c095	259	if (arg->fn(tp, f, arg) < 0) {
1da177e4 LT	260	arg->stop = 1;
	261	break;
	262	}
	263	skip:
	264	arg->count++;
	265	}
	266	}
	267
07d79fc7 CW	268	static void basic_bind_class(void *fh, u32 classid, unsigned long cl)
	269	{
	270	struct basic_filter *f = fh;
	271
	272	if (f && f->res.classid == classid)
	273	f->res.class = cl;
	274	}
	275
8113c095	276	static int basic_dump(struct net net, struct tcf_proto tp, void *fh,
1da177e4 LT	277	struct sk_buff skb, struct tcmsg t)
1da177e4 LT	278	{
8113c095	279	struct basic_filter *f = fh;
4b3550ef	280	struct nlattr *nest;
1da177e4 LT	281
	282	if (f == NULL)
	283	return skb->len;
	284
	285	t->tcm_handle = f->handle;
	286
4b3550ef PM	287	nest = nla_nest_start(skb, TCA_OPTIONS);
	288	if (nest == NULL)
	289	goto nla_put_failure;
1da177e4	290
1b34ec43 DM	291	if (f->res.classid &&
	292	nla_put_u32(skb, TCA_BASIC_CLASSID, f->res.classid))
	293	goto nla_put_failure;
e1e284a4	294
5da57f42	295	if (tcf_exts_dump(skb, &f->exts) < 0 \|\|
1da177e4	296	tcf_em_tree_dump(skb, &f->ematches, TCA_BASIC_EMATCHES) < 0)
add93b61	297	goto nla_put_failure;
1da177e4	298
4b3550ef	299	nla_nest_end(skb, nest);
4c46ee52	300
5da57f42	301	if (tcf_exts_dump_stats(skb, &f->exts) < 0)
4c46ee52	302	goto nla_put_failure;
4c46ee52	303
1da177e4 LT	304	return skb->len;
1da177e4 LT	305
add93b61	306	nla_put_failure:
4b3550ef	307	nla_nest_cancel(skb, nest);
1da177e4 LT	308	return -1;
	309	}
	310
2eb9d75c	311	static struct tcf_proto_ops cls_basic_ops __read_mostly = {
1da177e4 LT	312	.kind = "basic",
	313	.classify = basic_classify,
	314	.init = basic_init,
	315	.destroy = basic_destroy,
	316	.get = basic_get,
1da177e4 LT	317	.change = basic_change,
	318	.delete = basic_delete,
	319	.walk = basic_walk,
	320	.dump = basic_dump,
07d79fc7	321	.bind_class = basic_bind_class,
1da177e4 LT	322	.owner = THIS_MODULE,
	323	};
	324
	325	static int __init init_basic(void)
	326	{
	327	return register_tcf_proto_ops(&cls_basic_ops);
	328	}
	329
10297b99	330	static void __exit exit_basic(void)
1da177e4 LT	331	{
	332	unregister_tcf_proto_ops(&cls_basic_ops);
	333	}
	334
	335	module_init(init_basic)
	336	module_exit(exit_basic)
	337	MODULE_LICENSE("GPL");
	338