[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;

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

	return l;
}

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);

	tcf_exts_destroy(&f->exts);
	tcf_em_tree_destroy(&f->ematches);
	kfree(f);
}

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

	if (!force && !list_empty(&head->flist))
		return false;

	list_for_each_entry_safe(f, n, &head->flist, link) {
		list_del_rcu(&f->link);
		tcf_unbind_filter(tp, &f->res);
		call_rcu(&f->rcu, basic_delete_filter);
	}
	kfree_rcu(head, rcu);
	return true;
}

static int basic_delete(struct tcf_proto *tp, unsigned long arg)
{
	struct basic_filter *f = (struct basic_filter *) arg;

	list_del_rcu(&f->link);
	tcf_unbind_filter(tp, &f->res);
	call_rcu(&f->rcu, basic_delete_filter);
	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;
	struct tcf_exts e;
	struct tcf_ematch_tree t;

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

	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;
	}

	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;

	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);
		tcf_unbind_filter(tp, &fold->res);
		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, (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,
	.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;
1da177e4 LT	64
1c1bc6bd DB	65	list_for_each_entry(f, &head->flist, link) {
1c1bc6bd DB	66	if (f->handle == handle) {
1da177e4	67	l = (unsigned long) f;
1c1bc6bd DB	68	break;
	69	}
	70	}
1da177e4 LT	71
	72	return l;
	73	}
	74
1da177e4 LT	75	static int basic_init(struct tcf_proto *tp)
1da177e4 LT	76	{
d3fa76ee PM	77	struct basic_head *head;
	78
	79	head = kzalloc(sizeof(*head), GFP_KERNEL);
	80	if (head == NULL)
	81	return -ENOBUFS;
	82	INIT_LIST_HEAD(&head->flist);
9888faef	83	rcu_assign_pointer(tp->root, head);
1da177e4 LT	84	return 0;
	85	}
	86
9888faef	87	static void basic_delete_filter(struct rcu_head *head)
1da177e4	88	{
9888faef	89	struct basic_filter *f = container_of(head, struct basic_filter, rcu);
9888faef	90
18d0264f	91	tcf_exts_destroy(&f->exts);
82a470f1	92	tcf_em_tree_destroy(&f->ematches);
1da177e4 LT	93	kfree(f);
	94	}
	95
1e052be6	96	static bool basic_destroy(struct tcf_proto *tp, bool force)
1da177e4	97	{
9888faef	98	struct basic_head *head = rtnl_dereference(tp->root);
1da177e4	99	struct basic_filter f, n;
10297b99	100
1e052be6 CW	101	if (!force && !list_empty(&head->flist))
	102	return false;
	103
1da177e4	104	list_for_each_entry_safe(f, n, &head->flist, link) {
9888faef	105	list_del_rcu(&f->link);
18cdb37e	106	tcf_unbind_filter(tp, &f->res);
9888faef	107	call_rcu(&f->rcu, basic_delete_filter);
1da177e4	108	}
9888faef	109	kfree_rcu(head, rcu);
1e052be6	110	return true;
1da177e4 LT	111	}
	112
	113	static int basic_delete(struct tcf_proto *tp, unsigned long arg)
	114	{
e4386456	115	struct basic_filter f = (struct basic_filter ) arg;
1da177e4	116
e4386456 JP	117	list_del_rcu(&f->link);
	118	tcf_unbind_filter(tp, &f->res);
	119	call_rcu(&f->rcu, basic_delete_filter);
	120	return 0;
1da177e4 LT	121	}
1da177e4 LT	122
6fa8c014 PM	123	static const struct nla_policy basic_policy[TCA_BASIC_MAX + 1] = {
	124	[TCA_BASIC_CLASSID] = { .type = NLA_U32 },
	125	[TCA_BASIC_EMATCHES] = { .type = NLA_NESTED },
	126	};
	127
c1b52739 BL	128	static int basic_set_parms(struct net net, struct tcf_proto tp,
	129	struct basic_filter *f, unsigned long base,
	130	struct nlattr **tb,
2f7ef2f8	131	struct nlattr *est, bool ovr)
1da177e4	132	{
6459082a	133	int err;
1da177e4 LT	134	struct tcf_exts e;
	135	struct tcf_ematch_tree t;
	136
b9a24bb7	137	err = tcf_exts_init(&e, TCA_BASIC_ACT, TCA_BASIC_POLICE);
1da177e4 LT	138	if (err < 0)
1da177e4 LT	139	return err;
b9a24bb7 WC	140	err = tcf_exts_validate(net, tp, tb, est, &e, ovr);
	141	if (err < 0)
	142	goto errout;
1da177e4	143
add93b61	144	err = tcf_em_tree_validate(tp, tb[TCA_BASIC_EMATCHES], &t);
1da177e4 LT	145	if (err < 0)
	146	goto errout;
	147
add93b61	148	if (tb[TCA_BASIC_CLASSID]) {
1587bac4	149	f->res.classid = nla_get_u32(tb[TCA_BASIC_CLASSID]);
1da177e4 LT	150	tcf_bind_filter(tp, &f->res, base);
	151	}
	152
	153	tcf_exts_change(tp, &f->exts, &e);
	154	tcf_em_tree_change(tp, &f->ematches, &t);
9888faef	155	f->tp = tp;
1da177e4 LT	156
	157	return 0;
	158	errout:
18d0264f	159	tcf_exts_destroy(&e);
1da177e4 LT	160	return err;
	161	}
	162
c1b52739	163	static int basic_change(struct net net, struct sk_buff in_skb,
af4c6641	164	struct tcf_proto *tp, unsigned long base, u32 handle,
2f7ef2f8	165	struct nlattr *tca, unsigned long arg, bool ovr)
1da177e4	166	{
cee63723	167	int err;
9888faef	168	struct basic_head *head = rtnl_dereference(tp->root);
add93b61	169	struct nlattr *tb[TCA_BASIC_MAX + 1];
9888faef JF	170	struct basic_filter fold = (struct basic_filter ) *arg;
9888faef JF	171	struct basic_filter *fnew;
1da177e4	172
add93b61	173	if (tca[TCA_OPTIONS] == NULL)
1da177e4 LT	174	return -EINVAL;
1da177e4 LT	175
6fa8c014 PM	176	err = nla_parse_nested(tb, TCA_BASIC_MAX, tca[TCA_OPTIONS],
6fa8c014 PM	177	basic_policy);
cee63723 PM	178	if (err < 0)
cee63723 PM	179	return err;
1da177e4	180
9888faef JF	181	if (fold != NULL) {
9888faef JF	182	if (handle && fold->handle != handle)
1da177e4	183	return -EINVAL;
1da177e4 LT	184	}
1da177e4 LT	185
9888faef	186	fnew = kzalloc(sizeof(*fnew), GFP_KERNEL);
bd42b788 JP	187	if (!fnew)
bd42b788 JP	188	return -ENOBUFS;
1da177e4	189
b9a24bb7 WC	190	err = tcf_exts_init(&fnew->exts, TCA_BASIC_ACT, TCA_BASIC_POLICE);
	191	if (err < 0)
	192	goto errout;
	193
1da177e4	194	err = -EINVAL;
9888faef JF	195	if (handle) {
	196	fnew->handle = handle;
	197	} else if (fold) {
	198	fnew->handle = fold->handle;
	199	} else {
658270a0	200	unsigned int i = 0x80000000;
1da177e4 LT	201	do {
	202	if (++head->hgenerator == 0x7FFFFFFF)
	203	head->hgenerator = 1;
	204	} while (--i > 0 && basic_get(tp, head->hgenerator));
	205
	206	if (i <= 0) {
cc7ec456	207	pr_err("Insufficient number of handles\n");
1da177e4 LT	208	goto errout;
	209	}
	210
9888faef	211	fnew->handle = head->hgenerator;
1da177e4 LT	212	}
1da177e4 LT	213
9888faef	214	err = basic_set_parms(net, tp, fnew, base, tb, tca[TCA_RATE], ovr);
1da177e4 LT	215	if (err < 0)
	216	goto errout;
	217
9888faef JF	218	*arg = (unsigned long)fnew;
	219
	220	if (fold) {
	221	list_replace_rcu(&fold->link, &fnew->link);
18cdb37e	222	tcf_unbind_filter(tp, &fold->res);
9888faef JF	223	call_rcu(&fold->rcu, basic_delete_filter);
	224	} else {
	225	list_add_rcu(&fnew->link, &head->flist);
	226	}
1da177e4 LT	227
	228	return 0;
	229	errout:
b9a24bb7	230	tcf_exts_destroy(&fnew->exts);
9888faef	231	kfree(fnew);
1da177e4 LT	232	return err;
	233	}
	234
	235	static void basic_walk(struct tcf_proto tp, struct tcf_walker arg)
	236	{
9888faef	237	struct basic_head *head = rtnl_dereference(tp->root);
1da177e4 LT	238	struct basic_filter *f;
	239
	240	list_for_each_entry(f, &head->flist, link) {
	241	if (arg->count < arg->skip)
	242	goto skip;
	243
	244	if (arg->fn(tp, (unsigned long) f, arg) < 0) {
	245	arg->stop = 1;
	246	break;
	247	}
	248	skip:
	249	arg->count++;
	250	}
	251	}
	252
832d1d5b	253	static int basic_dump(struct net net, struct tcf_proto tp, unsigned long fh,
1da177e4 LT	254	struct sk_buff skb, struct tcmsg t)
	255	{
	256	struct basic_filter f = (struct basic_filter ) fh;
4b3550ef	257	struct nlattr *nest;
1da177e4 LT	258
	259	if (f == NULL)
	260	return skb->len;
	261
	262	t->tcm_handle = f->handle;
	263
4b3550ef PM	264	nest = nla_nest_start(skb, TCA_OPTIONS);
	265	if (nest == NULL)
	266	goto nla_put_failure;
1da177e4	267
1b34ec43 DM	268	if (f->res.classid &&
	269	nla_put_u32(skb, TCA_BASIC_CLASSID, f->res.classid))
	270	goto nla_put_failure;
e1e284a4	271
5da57f42	272	if (tcf_exts_dump(skb, &f->exts) < 0 \|\|
1da177e4	273	tcf_em_tree_dump(skb, &f->ematches, TCA_BASIC_EMATCHES) < 0)
add93b61	274	goto nla_put_failure;
1da177e4	275
4b3550ef	276	nla_nest_end(skb, nest);
4c46ee52	277
5da57f42	278	if (tcf_exts_dump_stats(skb, &f->exts) < 0)
4c46ee52	279	goto nla_put_failure;
4c46ee52	280
1da177e4 LT	281	return skb->len;
1da177e4 LT	282
add93b61	283	nla_put_failure:
4b3550ef	284	nla_nest_cancel(skb, nest);
1da177e4 LT	285	return -1;
	286	}
	287
2eb9d75c	288	static struct tcf_proto_ops cls_basic_ops __read_mostly = {
1da177e4 LT	289	.kind = "basic",
	290	.classify = basic_classify,
	291	.init = basic_init,
	292	.destroy = basic_destroy,
	293	.get = basic_get,
1da177e4 LT	294	.change = basic_change,
	295	.delete = basic_delete,
	296	.walk = basic_walk,
	297	.dump = basic_dump,
	298	.owner = THIS_MODULE,
	299	};
	300
	301	static int __init init_basic(void)
	302	{
	303	return register_tcf_proto_ops(&cls_basic_ops);
	304	}
	305
10297b99	306	static void __exit exit_basic(void)
1da177e4 LT	307	{
	308	unregister_tcf_proto_ops(&cls_basic_ops);
	309	}
	310
	311	module_init(init_basic)
	312	module_exit(exit_basic)
	313	MODULE_LICENSE("GPL");
	314