[mirror_ubuntu-zesty-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 <net/netlink.h>
#include <net/act_api.h>
#include <net/pkt_cls.h>

struct basic_head {
	u32			hgenerator;
	struct list_head	flist;
	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;
	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 unsigned long basic_get(struct tcf_proto *tp, u32 handle)
{
	unsigned long l = 0UL;
	struct basic_head *head = rtnl_dereference(tp->root);
	struct basic_filter *f;

	if (head == NULL)
		return 0UL;

	list_for_each_entry(f, &head->flist, link)
		if (f->handle == handle)
			l = (unsigned long) f;

	return l;
}

static void basic_put(struct tcf_proto *tp, unsigned long f)
{
}

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);
	rcu_assign_pointer(tp->root, head);
	return 0;
}

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

	tcf_unbind_filter(tp, &f->res);
	tcf_exts_destroy(&f->exts);
	tcf_em_tree_destroy(tp, &f->ematches);
	kfree(f);
}

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);
		call_rcu(&f->rcu, basic_delete_filter);
	}
	RCU_INIT_POINTER(tp->root, NULL);
	kfree_rcu(head, rcu);
}

static int basic_delete(struct tcf_proto *tp, unsigned long arg)
{
	struct basic_head *head = rtnl_dereference(tp->root);
	struct basic_filter *t, *f = (struct basic_filter *) arg;

	list_for_each_entry(t, &head->flist, link)
		if (t == f) {
			list_del_rcu(&t->link);
			call_rcu(&t->rcu, basic_delete_filter);
			return 0;
		}

	return -ENOENT;
}

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;
	struct tcf_exts e;
	struct tcf_ematch_tree t;

	tcf_exts_init(&e, TCA_BASIC_ACT, TCA_BASIC_POLICE);
	err = tcf_exts_validate(net, tp, tb, est, &e, ovr);
	if (err < 0)
		return err;

	err = tcf_em_tree_validate(tp, tb[TCA_BASIC_EMATCHES], &t);
	if (err < 0)
		goto errout;

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

	tcf_exts_change(tp, &f->exts, &e);
	tcf_em_tree_change(tp, &f->ematches, &t);
	f->tp = tp;

	return 0;
errout:
	tcf_exts_destroy(&e);
	return err;
}

static int basic_change(struct net *net, struct sk_buff *in_skb,
			struct tcf_proto *tp, unsigned long base, u32 handle,
			struct nlattr **tca, unsigned long *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;

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

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

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

	err = -ENOBUFS;
	fnew = kzalloc(sizeof(*fnew), GFP_KERNEL);
	if (fnew == NULL)
		goto errout;

	tcf_exts_init(&fnew->exts, TCA_BASIC_ACT, TCA_BASIC_POLICE);
	err = -EINVAL;
	if (handle) {
		fnew->handle = handle;
	} else if (fold) {
		fnew->handle = fold->handle;
	} else {
		unsigned int i = 0x80000000;
		do {
			if (++head->hgenerator == 0x7FFFFFFF)
				head->hgenerator = 1;
		} while (--i > 0 && basic_get(tp, head->hgenerator));

		if (i <= 0) {
			pr_err("Insufficient number of handles\n");
			goto errout;
		}

		fnew->handle = head->hgenerator;
	}

	err = basic_set_parms(net, tp, fnew, base, tb, tca[TCA_RATE], ovr);
	if (err < 0)
		goto errout;

	*arg = (unsigned long)fnew;

	if (fold) {
		list_replace_rcu(&fold->link, &fnew->link);
		call_rcu(&fold->rcu, basic_delete_filter);
	} else {
		list_add_rcu(&fnew->link, &head->flist);
	}

	return 0;
errout:
	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, (unsigned long) f, arg) < 0) {
			arg->stop = 1;
			break;
		}
skip:
		arg->count++;
	}
}

static int basic_dump(struct net *net, struct tcf_proto *tp, unsigned long fh,
		      struct sk_buff *skb, struct tcmsg *t)
{
	struct basic_filter *f = (struct basic_filter *) 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,
	.put		=	basic_put,
	.change		=	basic_change,
	.delete		=	basic_delete,
	.walk		=	basic_walk,
	.dump		=	basic_dump,
	.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>
dc5fc579	20	#include <net/netlink.h>
1da177e4 LT	21	#include <net/act_api.h>
	22	#include <net/pkt_cls.h>
	23
cc7ec456	24	struct basic_head {
1da177e4 LT	25	u32 hgenerator;
1da177e4 LT	26	struct list_head flist;
9888faef	27	struct rcu_head rcu;
1da177e4 LT	28	};
1da177e4 LT	29
cc7ec456	30	struct basic_filter {
1da177e4 LT	31	u32 handle;
	32	struct tcf_exts exts;
	33	struct tcf_ematch_tree ematches;
	34	struct tcf_result res;
9888faef	35	struct tcf_proto *tp;
1da177e4	36	struct list_head link;
9888faef	37	struct rcu_head rcu;
1da177e4 LT	38	};
1da177e4 LT	39
dc7f9f6e	40	static int basic_classify(struct sk_buff skb, const struct tcf_proto tp,
1da177e4 LT	41	struct tcf_result *res)
	42	{
	43	int r;
9888faef	44	struct basic_head *head = rcu_dereference_bh(tp->root);
1da177e4 LT	45	struct basic_filter *f;
1da177e4 LT	46
9888faef	47	list_for_each_entry_rcu(f, &head->flist, link) {
1da177e4 LT	48	if (!tcf_em_tree_match(skb, &f->ematches, NULL))
	49	continue;
	50	*res = f->res;
	51	r = tcf_exts_exec(skb, &f->exts, res);
	52	if (r < 0)
	53	continue;
	54	return r;
	55	}
	56	return -1;
	57	}
	58
	59	static unsigned long basic_get(struct tcf_proto *tp, u32 handle)
	60	{
	61	unsigned long l = 0UL;
9888faef	62	struct basic_head *head = rtnl_dereference(tp->root);
1da177e4 LT	63	struct basic_filter *f;
	64
	65	if (head == NULL)
	66	return 0UL;
	67
	68	list_for_each_entry(f, &head->flist, link)
	69	if (f->handle == handle)
	70	l = (unsigned long) f;
	71
	72	return l;
	73	}
	74
	75	static void basic_put(struct tcf_proto *tp, unsigned long f)
	76	{
	77	}
	78
	79	static int basic_init(struct tcf_proto *tp)
	80	{
d3fa76ee PM	81	struct basic_head *head;
	82
	83	head = kzalloc(sizeof(*head), GFP_KERNEL);
	84	if (head == NULL)
	85	return -ENOBUFS;
	86	INIT_LIST_HEAD(&head->flist);
9888faef	87	rcu_assign_pointer(tp->root, head);
1da177e4 LT	88	return 0;
	89	}
	90
9888faef	91	static void basic_delete_filter(struct rcu_head *head)
1da177e4	92	{
9888faef JF	93	struct basic_filter *f = container_of(head, struct basic_filter, rcu);
	94	struct tcf_proto *tp = f->tp;
	95
1da177e4	96	tcf_unbind_filter(tp, &f->res);
18d0264f	97	tcf_exts_destroy(&f->exts);
1da177e4 LT	98	tcf_em_tree_destroy(tp, &f->ematches);
	99	kfree(f);
	100	}
	101
	102	static void basic_destroy(struct tcf_proto *tp)
	103	{
9888faef	104	struct basic_head *head = rtnl_dereference(tp->root);
1da177e4	105	struct basic_filter f, n;
10297b99	106
1da177e4	107	list_for_each_entry_safe(f, n, &head->flist, link) {
9888faef JF	108	list_del_rcu(&f->link);
9888faef JF	109	call_rcu(&f->rcu, basic_delete_filter);
1da177e4	110	}
9888faef JF	111	RCU_INIT_POINTER(tp->root, NULL);
9888faef JF	112	kfree_rcu(head, rcu);
1da177e4 LT	113	}
	114
	115	static int basic_delete(struct tcf_proto *tp, unsigned long arg)
	116	{
9888faef	117	struct basic_head *head = rtnl_dereference(tp->root);
1da177e4 LT	118	struct basic_filter t, f = (struct basic_filter *) arg;
	119
	120	list_for_each_entry(t, &head->flist, link)
	121	if (t == f) {
9888faef JF	122	list_del_rcu(&t->link);
9888faef JF	123	call_rcu(&t->rcu, basic_delete_filter);
1da177e4 LT	124	return 0;
	125	}
	126
	127	return -ENOENT;
	128	}
	129
6fa8c014 PM	130	static const struct nla_policy basic_policy[TCA_BASIC_MAX + 1] = {
	131	[TCA_BASIC_CLASSID] = { .type = NLA_U32 },
	132	[TCA_BASIC_EMATCHES] = { .type = NLA_NESTED },
	133	};
	134
c1b52739 BL	135	static int basic_set_parms(struct net net, struct tcf_proto tp,
	136	struct basic_filter *f, unsigned long base,
	137	struct nlattr **tb,
2f7ef2f8	138	struct nlattr *est, bool ovr)
1da177e4	139	{
6459082a	140	int err;
1da177e4 LT	141	struct tcf_exts e;
	142	struct tcf_ematch_tree t;
	143
5da57f42	144	tcf_exts_init(&e, TCA_BASIC_ACT, TCA_BASIC_POLICE);
2f7ef2f8	145	err = tcf_exts_validate(net, tp, tb, est, &e, ovr);
1da177e4 LT	146	if (err < 0)
	147	return err;
	148
add93b61	149	err = tcf_em_tree_validate(tp, tb[TCA_BASIC_EMATCHES], &t);
1da177e4 LT	150	if (err < 0)
	151	goto errout;
	152
add93b61	153	if (tb[TCA_BASIC_CLASSID]) {
1587bac4	154	f->res.classid = nla_get_u32(tb[TCA_BASIC_CLASSID]);
1da177e4 LT	155	tcf_bind_filter(tp, &f->res, base);
	156	}
	157
	158	tcf_exts_change(tp, &f->exts, &e);
	159	tcf_em_tree_change(tp, &f->ematches, &t);
9888faef	160	f->tp = tp;
1da177e4 LT	161
	162	return 0;
	163	errout:
18d0264f	164	tcf_exts_destroy(&e);
1da177e4 LT	165	return err;
	166	}
	167
c1b52739	168	static int basic_change(struct net net, struct sk_buff in_skb,
af4c6641	169	struct tcf_proto *tp, unsigned long base, u32 handle,
2f7ef2f8	170	struct nlattr *tca, unsigned long arg, bool ovr)
1da177e4	171	{
cee63723	172	int err;
9888faef	173	struct basic_head *head = rtnl_dereference(tp->root);
add93b61	174	struct nlattr *tb[TCA_BASIC_MAX + 1];
9888faef JF	175	struct basic_filter fold = (struct basic_filter ) *arg;
9888faef JF	176	struct basic_filter *fnew;
1da177e4	177
add93b61	178	if (tca[TCA_OPTIONS] == NULL)
1da177e4 LT	179	return -EINVAL;
1da177e4 LT	180
6fa8c014 PM	181	err = nla_parse_nested(tb, TCA_BASIC_MAX, tca[TCA_OPTIONS],
6fa8c014 PM	182	basic_policy);
cee63723 PM	183	if (err < 0)
cee63723 PM	184	return err;
1da177e4	185
9888faef JF	186	if (fold != NULL) {
9888faef JF	187	if (handle && fold->handle != handle)
1da177e4	188	return -EINVAL;
1da177e4 LT	189	}
	190
	191	err = -ENOBUFS;
9888faef JF	192	fnew = kzalloc(sizeof(*fnew), GFP_KERNEL);
9888faef JF	193	if (fnew == NULL)
1da177e4	194	goto errout;
1da177e4	195
9888faef	196	tcf_exts_init(&fnew->exts, TCA_BASIC_ACT, TCA_BASIC_POLICE);
1da177e4	197	err = -EINVAL;
9888faef JF	198	if (handle) {
	199	fnew->handle = handle;
	200	} else if (fold) {
	201	fnew->handle = fold->handle;
	202	} else {
658270a0	203	unsigned int i = 0x80000000;
1da177e4 LT	204	do {
	205	if (++head->hgenerator == 0x7FFFFFFF)
	206	head->hgenerator = 1;
	207	} while (--i > 0 && basic_get(tp, head->hgenerator));
	208
	209	if (i <= 0) {
cc7ec456	210	pr_err("Insufficient number of handles\n");
1da177e4 LT	211	goto errout;
	212	}
	213
9888faef	214	fnew->handle = head->hgenerator;
1da177e4 LT	215	}
1da177e4 LT	216
9888faef	217	err = basic_set_parms(net, tp, fnew, base, tb, tca[TCA_RATE], ovr);
1da177e4 LT	218	if (err < 0)
	219	goto errout;
	220
9888faef JF	221	*arg = (unsigned long)fnew;
	222
	223	if (fold) {
	224	list_replace_rcu(&fold->link, &fnew->link);
	225	call_rcu(&fold->rcu, basic_delete_filter);
	226	} else {
	227	list_add_rcu(&fnew->link, &head->flist);
	228	}
1da177e4 LT	229
	230	return 0;
	231	errout:
9888faef	232	kfree(fnew);
1da177e4 LT	233	return err;
	234	}
	235
	236	static void basic_walk(struct tcf_proto tp, struct tcf_walker arg)
	237	{
9888faef	238	struct basic_head *head = rtnl_dereference(tp->root);
1da177e4 LT	239	struct basic_filter *f;
	240
	241	list_for_each_entry(f, &head->flist, link) {
	242	if (arg->count < arg->skip)
	243	goto skip;
	244
	245	if (arg->fn(tp, (unsigned long) f, arg) < 0) {
	246	arg->stop = 1;
	247	break;
	248	}
	249	skip:
	250	arg->count++;
	251	}
	252	}
	253
832d1d5b	254	static int basic_dump(struct net net, struct tcf_proto tp, unsigned long fh,
1da177e4 LT	255	struct sk_buff skb, struct tcmsg t)
	256	{
	257	struct basic_filter f = (struct basic_filter ) fh;
4b3550ef	258	struct nlattr *nest;
1da177e4 LT	259
	260	if (f == NULL)
	261	return skb->len;
	262
	263	t->tcm_handle = f->handle;
	264
4b3550ef PM	265	nest = nla_nest_start(skb, TCA_OPTIONS);
	266	if (nest == NULL)
	267	goto nla_put_failure;
1da177e4	268
1b34ec43 DM	269	if (f->res.classid &&
	270	nla_put_u32(skb, TCA_BASIC_CLASSID, f->res.classid))
	271	goto nla_put_failure;
e1e284a4	272
5da57f42	273	if (tcf_exts_dump(skb, &f->exts) < 0 \|\|
1da177e4	274	tcf_em_tree_dump(skb, &f->ematches, TCA_BASIC_EMATCHES) < 0)
add93b61	275	goto nla_put_failure;
1da177e4	276
4b3550ef	277	nla_nest_end(skb, nest);
4c46ee52	278
5da57f42	279	if (tcf_exts_dump_stats(skb, &f->exts) < 0)
4c46ee52	280	goto nla_put_failure;
4c46ee52	281
1da177e4 LT	282	return skb->len;
1da177e4 LT	283
add93b61	284	nla_put_failure:
4b3550ef	285	nla_nest_cancel(skb, nest);
1da177e4 LT	286	return -1;
	287	}
	288
2eb9d75c	289	static struct tcf_proto_ops cls_basic_ops __read_mostly = {
1da177e4 LT	290	.kind = "basic",
	291	.classify = basic_classify,
	292	.init = basic_init,
	293	.destroy = basic_destroy,
	294	.get = basic_get,
	295	.put = basic_put,
	296	.change = basic_change,
	297	.delete = basic_delete,
	298	.walk = basic_walk,
	299	.dump = basic_dump,
	300	.owner = THIS_MODULE,
	301	};
	302
	303	static int __init init_basic(void)
	304	{
	305	return register_tcf_proto_ops(&cls_basic_ops);
	306	}
	307
10297b99	308	static void __exit exit_basic(void)
1da177e4 LT	309	{
	310	unregister_tcf_proto_ops(&cls_basic_ops);
	311	}
	312
	313	module_init(init_basic)
	314	module_exit(exit_basic)
	315	MODULE_LICENSE("GPL");
	316