[linux-2.6-block.git] / net / sched / act_pedit.c

/*
 * net/sched/act_pedit.c	Generic packet editor
 *
 *		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:	Jamal Hadi Salim (2002-4)
 */

#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/string.h>
#include <linux/errno.h>
#include <linux/skbuff.h>
#include <linux/rtnetlink.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <net/netlink.h>
#include <net/pkt_sched.h>
#include <linux/tc_act/tc_pedit.h>
#include <net/tc_act/tc_pedit.h>

#define PEDIT_TAB_MASK	15

static int pedit_net_id;

static const struct nla_policy pedit_policy[TCA_PEDIT_MAX + 1] = {
	[TCA_PEDIT_PARMS]	= { .len = sizeof(struct tc_pedit) },
};

static int tcf_pedit_init(struct net *net, struct nlattr *nla,
			  struct nlattr *est, struct tc_action *a,
			  int ovr, int bind)
{
	struct tc_action_net *tn = net_generic(net, pedit_net_id);
	struct nlattr *tb[TCA_PEDIT_MAX + 1];
	struct tc_pedit *parm;
	int ret = 0, err;
	struct tcf_pedit *p;
	struct tc_pedit_key *keys = NULL;
	int ksize;

	if (nla == NULL)
		return -EINVAL;

	err = nla_parse_nested(tb, TCA_PEDIT_MAX, nla, pedit_policy);
	if (err < 0)
		return err;

	if (tb[TCA_PEDIT_PARMS] == NULL)
		return -EINVAL;
	parm = nla_data(tb[TCA_PEDIT_PARMS]);
	ksize = parm->nkeys * sizeof(struct tc_pedit_key);
	if (nla_len(tb[TCA_PEDIT_PARMS]) < sizeof(*parm) + ksize)
		return -EINVAL;

	if (!tcf_hash_check(tn, parm->index, a, bind)) {
		if (!parm->nkeys)
			return -EINVAL;
		ret = tcf_hash_create(tn, parm->index, est, a,
				      sizeof(*p), bind, false);
		if (ret)
			return ret;
		p = to_pedit(a);
		keys = kmalloc(ksize, GFP_KERNEL);
		if (keys == NULL) {
			tcf_hash_cleanup(a, est);
			return -ENOMEM;
		}
		ret = ACT_P_CREATED;
	} else {
		if (bind)
			return 0;
		tcf_hash_release(a, bind);
		if (!ovr)
			return -EEXIST;
		p = to_pedit(a);
		if (p->tcfp_nkeys && p->tcfp_nkeys != parm->nkeys) {
			keys = kmalloc(ksize, GFP_KERNEL);
			if (keys == NULL)
				return -ENOMEM;
		}
	}

	spin_lock_bh(&p->tcf_lock);
	p->tcfp_flags = parm->flags;
	p->tcf_action = parm->action;
	if (keys) {
		kfree(p->tcfp_keys);
		p->tcfp_keys = keys;
		p->tcfp_nkeys = parm->nkeys;
	}
	memcpy(p->tcfp_keys, parm->keys, ksize);
	spin_unlock_bh(&p->tcf_lock);
	if (ret == ACT_P_CREATED)
		tcf_hash_insert(tn, a);
	return ret;
}

static void tcf_pedit_cleanup(struct tc_action *a, int bind)
{
	struct tcf_pedit *p = a->priv;
	struct tc_pedit_key *keys = p->tcfp_keys;
	kfree(keys);
}

static int tcf_pedit(struct sk_buff *skb, const struct tc_action *a,
		     struct tcf_result *res)
{
	struct tcf_pedit *p = a->priv;
	int i;
	unsigned int off;

	if (skb_unclone(skb, GFP_ATOMIC))
		return p->tcf_action;

	off = skb_network_offset(skb);

	spin_lock(&p->tcf_lock);

	p->tcf_tm.lastuse = jiffies;

	if (p->tcfp_nkeys > 0) {
		struct tc_pedit_key *tkey = p->tcfp_keys;

		for (i = p->tcfp_nkeys; i > 0; i--, tkey++) {
			u32 *ptr, _data;
			int offset = tkey->off;

			if (tkey->offmask) {
				char *d, _d;

				d = skb_header_pointer(skb, off + tkey->at, 1,
						       &_d);
				if (!d)
					goto bad;
				offset += (*d & tkey->offmask) >> tkey->shift;
			}

			if (offset % 4) {
				pr_info("tc filter pedit"
					" offset must be on 32 bit boundaries\n");
				goto bad;
			}
			if (offset > 0 && offset > skb->len) {
				pr_info("tc filter pedit"
					" offset %d can't exceed pkt length %d\n",
				       offset, skb->len);
				goto bad;
			}

			ptr = skb_header_pointer(skb, off + offset, 4, &_data);
			if (!ptr)
				goto bad;
			/* just do it, baby */
			*ptr = ((*ptr & tkey->mask) ^ tkey->val);
			if (ptr == &_data)
				skb_store_bits(skb, off + offset, ptr, 4);
		}

		goto done;
	} else
		WARN(1, "pedit BUG: index %d\n", p->tcf_index);

bad:
	p->tcf_qstats.overlimits++;
done:
	bstats_update(&p->tcf_bstats, skb);
	spin_unlock(&p->tcf_lock);
	return p->tcf_action;
}

static int tcf_pedit_dump(struct sk_buff *skb, struct tc_action *a,
			  int bind, int ref)
{
	unsigned char *b = skb_tail_pointer(skb);
	struct tcf_pedit *p = a->priv;
	struct tc_pedit *opt;
	struct tcf_t t;
	int s;

	s = sizeof(*opt) + p->tcfp_nkeys * sizeof(struct tc_pedit_key);

	/* netlink spinlocks held above us - must use ATOMIC */
	opt = kzalloc(s, GFP_ATOMIC);
	if (unlikely(!opt))
		return -ENOBUFS;

	memcpy(opt->keys, p->tcfp_keys,
	       p->tcfp_nkeys * sizeof(struct tc_pedit_key));
	opt->index = p->tcf_index;
	opt->nkeys = p->tcfp_nkeys;
	opt->flags = p->tcfp_flags;
	opt->action = p->tcf_action;
	opt->refcnt = p->tcf_refcnt - ref;
	opt->bindcnt = p->tcf_bindcnt - bind;

	if (nla_put(skb, TCA_PEDIT_PARMS, s, opt))
		goto nla_put_failure;
	t.install = jiffies_to_clock_t(jiffies - p->tcf_tm.install);
	t.lastuse = jiffies_to_clock_t(jiffies - p->tcf_tm.lastuse);
	t.expires = jiffies_to_clock_t(p->tcf_tm.expires);
	if (nla_put_64bit(skb, TCA_PEDIT_TM, sizeof(t), &t, TCA_PEDIT_PAD))
		goto nla_put_failure;
	kfree(opt);
	return skb->len;

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

static int tcf_pedit_walker(struct net *net, struct sk_buff *skb,
			    struct netlink_callback *cb, int type,
			    struct tc_action *a)
{
	struct tc_action_net *tn = net_generic(net, pedit_net_id);

	return tcf_generic_walker(tn, skb, cb, type, a);
}

static int tcf_pedit_search(struct net *net, struct tc_action *a, u32 index)
{
	struct tc_action_net *tn = net_generic(net, pedit_net_id);

	return tcf_hash_search(tn, a, index);
}

static struct tc_action_ops act_pedit_ops = {
	.kind		=	"pedit",
	.type		=	TCA_ACT_PEDIT,
	.owner		=	THIS_MODULE,
	.act		=	tcf_pedit,
	.dump		=	tcf_pedit_dump,
	.cleanup	=	tcf_pedit_cleanup,
	.init		=	tcf_pedit_init,
	.walk		=	tcf_pedit_walker,
	.lookup		=	tcf_pedit_search,
};

static __net_init int pedit_init_net(struct net *net)
{
	struct tc_action_net *tn = net_generic(net, pedit_net_id);

	return tc_action_net_init(tn, &act_pedit_ops, PEDIT_TAB_MASK);
}

static void __net_exit pedit_exit_net(struct net *net)
{
	struct tc_action_net *tn = net_generic(net, pedit_net_id);

	tc_action_net_exit(tn);
}

static struct pernet_operations pedit_net_ops = {
	.init = pedit_init_net,
	.exit = pedit_exit_net,
	.id   = &pedit_net_id,
	.size = sizeof(struct tc_action_net),
};

MODULE_AUTHOR("Jamal Hadi Salim(2002-4)");
MODULE_DESCRIPTION("Generic Packet Editor actions");
MODULE_LICENSE("GPL");

static int __init pedit_init_module(void)
{
	return tcf_register_action(&act_pedit_ops, &pedit_net_ops);
}

static void __exit pedit_cleanup_module(void)
{
	tcf_unregister_action(&act_pedit_ops, &pedit_net_ops);
}

module_init(pedit_init_module);
module_exit(pedit_cleanup_module);
Commit	Line	Data
1da177e4	1	/*
0c6965dd	2	* net/sched/act_pedit.c Generic packet editor
1da177e4 LT	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: Jamal Hadi Salim (2002-4)
	10	*/
	11
1da177e4 LT	12	#include <linux/types.h>
1da177e4 LT	13	#include <linux/kernel.h>
1da177e4	14	#include <linux/string.h>
1da177e4	15	#include <linux/errno.h>
1da177e4 LT	16	#include <linux/skbuff.h>
	17	#include <linux/rtnetlink.h>
	18	#include <linux/module.h>
	19	#include <linux/init.h>
5a0e3ad6	20	#include <linux/slab.h>
dc5fc579	21	#include <net/netlink.h>
1da177e4 LT	22	#include <net/pkt_sched.h>
	23	#include <linux/tc_act/tc_pedit.h>
	24	#include <net/tc_act/tc_pedit.h>
	25
e9ce1cd3	26	#define PEDIT_TAB_MASK 15
1da177e4	27
ddf97ccd WC	28	static int pedit_net_id;
ddf97ccd WC	29
53b2bf3f	30	static const struct nla_policy pedit_policy[TCA_PEDIT_MAX + 1] = {
53f7e35f	31	[TCA_PEDIT_PARMS] = { .len = sizeof(struct tc_pedit) },
53b2bf3f PM	32	};
53b2bf3f PM	33
c1b52739 BL	34	static int tcf_pedit_init(struct net net, struct nlattr nla,
	35	struct nlattr est, struct tc_action a,
	36	int ovr, int bind)
1da177e4	37	{
ddf97ccd	38	struct tc_action_net *tn = net_generic(net, pedit_net_id);
7ba699c6	39	struct nlattr *tb[TCA_PEDIT_MAX + 1];
1da177e4	40	struct tc_pedit *parm;
cee63723	41	int ret = 0, err;
1da177e4 LT	42	struct tcf_pedit *p;
	43	struct tc_pedit_key *keys = NULL;
	44	int ksize;
	45
cee63723	46	if (nla == NULL)
1da177e4 LT	47	return -EINVAL;
1da177e4 LT	48
53b2bf3f	49	err = nla_parse_nested(tb, TCA_PEDIT_MAX, nla, pedit_policy);
cee63723 PM	50	if (err < 0)
	51	return err;
	52
53b2bf3f	53	if (tb[TCA_PEDIT_PARMS] == NULL)
1da177e4	54	return -EINVAL;
7ba699c6	55	parm = nla_data(tb[TCA_PEDIT_PARMS]);
1da177e4	56	ksize = parm->nkeys * sizeof(struct tc_pedit_key);
7ba699c6	57	if (nla_len(tb[TCA_PEDIT_PARMS]) < sizeof(*parm) + ksize)
1da177e4 LT	58	return -EINVAL;
1da177e4 LT	59
ddf97ccd	60	if (!tcf_hash_check(tn, parm->index, a, bind)) {
1da177e4 LT	61	if (!parm->nkeys)
1da177e4 LT	62	return -EINVAL;
ddf97ccd WC	63	ret = tcf_hash_create(tn, parm->index, est, a,
ddf97ccd WC	64	sizeof(*p), bind, false);
86062033 WC	65	if (ret)
	66	return ret;
	67	p = to_pedit(a);
1da177e4 LT	68	keys = kmalloc(ksize, GFP_KERNEL);
1da177e4 LT	69	if (keys == NULL) {
86062033	70	tcf_hash_cleanup(a, est);
1da177e4 LT	71	return -ENOMEM;
	72	}
	73	ret = ACT_P_CREATED;
	74	} else {
1a29321e JHS	75	if (bind)
1a29321e JHS	76	return 0;
5175f710	77	tcf_hash_release(a, bind);
1a29321e	78	if (!ovr)
1da177e4	79	return -EEXIST;
5175f710	80	p = to_pedit(a);
e9ce1cd3	81	if (p->tcfp_nkeys && p->tcfp_nkeys != parm->nkeys) {
1da177e4 LT	82	keys = kmalloc(ksize, GFP_KERNEL);
	83	if (keys == NULL)
	84	return -ENOMEM;
	85	}
	86	}
	87
e9ce1cd3 DM	88	spin_lock_bh(&p->tcf_lock);
	89	p->tcfp_flags = parm->flags;
	90	p->tcf_action = parm->action;
1da177e4	91	if (keys) {
e9ce1cd3 DM	92	kfree(p->tcfp_keys);
	93	p->tcfp_keys = keys;
	94	p->tcfp_nkeys = parm->nkeys;
1da177e4	95	}
e9ce1cd3 DM	96	memcpy(p->tcfp_keys, parm->keys, ksize);
e9ce1cd3 DM	97	spin_unlock_bh(&p->tcf_lock);
1da177e4	98	if (ret == ACT_P_CREATED)
ddf97ccd	99	tcf_hash_insert(tn, a);
1da177e4 LT	100	return ret;
	101	}
	102
a5b5c958	103	static void tcf_pedit_cleanup(struct tc_action *a, int bind)
1da177e4	104	{
e9ce1cd3	105	struct tcf_pedit *p = a->priv;
a5b5c958 WC	106	struct tc_pedit_key *keys = p->tcfp_keys;
a5b5c958 WC	107	kfree(keys);
1da177e4 LT	108	}
1da177e4 LT	109
dc7f9f6e	110	static int tcf_pedit(struct sk_buff skb, const struct tc_action a,
e9ce1cd3	111	struct tcf_result *res)
1da177e4	112	{
e9ce1cd3	113	struct tcf_pedit *p = a->priv;
4749c3ef	114	int i;
db2c2417	115	unsigned int off;
1da177e4	116
14bbd6a5	117	if (skb_unclone(skb, GFP_ATOMIC))
cc7ec456	118	return p->tcf_action;
1da177e4	119
db2c2417	120	off = skb_network_offset(skb);
1da177e4	121
e9ce1cd3	122	spin_lock(&p->tcf_lock);
1da177e4	123
e9ce1cd3	124	p->tcf_tm.lastuse = jiffies;
1da177e4	125
e9ce1cd3 DM	126	if (p->tcfp_nkeys > 0) {
e9ce1cd3 DM	127	struct tc_pedit_key *tkey = p->tcfp_keys;
1da177e4	128
e9ce1cd3	129	for (i = p->tcfp_nkeys; i > 0; i--, tkey++) {
db2c2417	130	u32 *ptr, _data;
1da177e4 LT	131	int offset = tkey->off;
	132
	133	if (tkey->offmask) {
db2c2417 CG	134	char *d, _d;
	135
	136	d = skb_header_pointer(skb, off + tkey->at, 1,
	137	&_d);
	138	if (!d)
1da177e4	139	goto bad;
db2c2417	140	offset += (*d & tkey->offmask) >> tkey->shift;
1da177e4 LT	141	}
	142
	143	if (offset % 4) {
6ff9c364	144	pr_info("tc filter pedit"
6ff9c364	145	" offset must be on 32 bit boundaries\n");
1da177e4 LT	146	goto bad;
1da177e4 LT	147	}
75202e76	148	if (offset > 0 && offset > skb->len) {
6ff9c364	149	pr_info("tc filter pedit"
25985edc	150	" offset %d can't exceed pkt length %d\n",
1da177e4 LT	151	offset, skb->len);
	152	goto bad;
	153	}
	154
db2c2417 CG	155	ptr = skb_header_pointer(skb, off + offset, 4, &_data);
	156	if (!ptr)
	157	goto bad;
1da177e4 LT	158	/* just do it, baby */
1da177e4 LT	159	ptr = ((ptr & tkey->mask) ^ tkey->val);
db2c2417 CG	160	if (ptr == &_data)
db2c2417 CG	161	skb_store_bits(skb, off + offset, ptr, 4);
1da177e4	162	}
10297b99	163
1da177e4	164	goto done;
6ff9c364	165	} else
6ff9c364	166	WARN(1, "pedit BUG: index %d\n", p->tcf_index);
1da177e4 LT	167
1da177e4 LT	168	bad:
e9ce1cd3	169	p->tcf_qstats.overlimits++;
1da177e4	170	done:
bfe0d029	171	bstats_update(&p->tcf_bstats, skb);
e9ce1cd3 DM	172	spin_unlock(&p->tcf_lock);
e9ce1cd3 DM	173	return p->tcf_action;
1da177e4 LT	174	}
1da177e4 LT	175
e9ce1cd3 DM	176	static int tcf_pedit_dump(struct sk_buff skb, struct tc_action a,
e9ce1cd3 DM	177	int bind, int ref)
1da177e4	178	{
27a884dc	179	unsigned char *b = skb_tail_pointer(skb);
e9ce1cd3	180	struct tcf_pedit *p = a->priv;
1da177e4	181	struct tc_pedit *opt;
1da177e4	182	struct tcf_t t;
10297b99 YH	183	int s;
10297b99 YH	184
e9ce1cd3	185	s = sizeof(opt) + p->tcfp_nkeys sizeof(struct tc_pedit_key);
1da177e4 LT	186
1da177e4 LT	187	/* netlink spinlocks held above us - must use ATOMIC */
0da974f4	188	opt = kzalloc(s, GFP_ATOMIC);
e9ce1cd3	189	if (unlikely(!opt))
1da177e4	190	return -ENOBUFS;
1da177e4	191
e9ce1cd3 DM	192	memcpy(opt->keys, p->tcfp_keys,
	193	p->tcfp_nkeys * sizeof(struct tc_pedit_key));
	194	opt->index = p->tcf_index;
	195	opt->nkeys = p->tcfp_nkeys;
	196	opt->flags = p->tcfp_flags;
	197	opt->action = p->tcf_action;
	198	opt->refcnt = p->tcf_refcnt - ref;
	199	opt->bindcnt = p->tcf_bindcnt - bind;
1da177e4	200
1b34ec43 DM	201	if (nla_put(skb, TCA_PEDIT_PARMS, s, opt))
1b34ec43 DM	202	goto nla_put_failure;
e9ce1cd3 DM	203	t.install = jiffies_to_clock_t(jiffies - p->tcf_tm.install);
	204	t.lastuse = jiffies_to_clock_t(jiffies - p->tcf_tm.lastuse);
	205	t.expires = jiffies_to_clock_t(p->tcf_tm.expires);
9854518e	206	if (nla_put_64bit(skb, TCA_PEDIT_TM, sizeof(t), &t, TCA_PEDIT_PAD))
1b34ec43	207	goto nla_put_failure;
541673c8	208	kfree(opt);
1da177e4 LT	209	return skb->len;
1da177e4 LT	210
7ba699c6	211	nla_put_failure:
dc5fc579	212	nlmsg_trim(skb, b);
541673c8	213	kfree(opt);
1da177e4 LT	214	return -1;
	215	}
	216
ddf97ccd WC	217	static int tcf_pedit_walker(struct net net, struct sk_buff skb,
	218	struct netlink_callback *cb, int type,
	219	struct tc_action *a)
	220	{
	221	struct tc_action_net *tn = net_generic(net, pedit_net_id);
	222
	223	return tcf_generic_walker(tn, skb, cb, type, a);
	224	}
	225
	226	static int tcf_pedit_search(struct net net, struct tc_action a, u32 index)
	227	{
	228	struct tc_action_net *tn = net_generic(net, pedit_net_id);
	229
	230	return tcf_hash_search(tn, a, index);
	231	}
	232
e9ce1cd3	233	static struct tc_action_ops act_pedit_ops = {
1da177e4 LT	234	.kind = "pedit",
1da177e4 LT	235	.type = TCA_ACT_PEDIT,
1da177e4 LT	236	.owner = THIS_MODULE,
	237	.act = tcf_pedit,
	238	.dump = tcf_pedit_dump,
	239	.cleanup = tcf_pedit_cleanup,
1da177e4	240	.init = tcf_pedit_init,
ddf97ccd WC	241	.walk = tcf_pedit_walker,
	242	.lookup = tcf_pedit_search,
	243	};
	244
	245	static __net_init int pedit_init_net(struct net *net)
	246	{
	247	struct tc_action_net *tn = net_generic(net, pedit_net_id);
	248
	249	return tc_action_net_init(tn, &act_pedit_ops, PEDIT_TAB_MASK);
	250	}
	251
	252	static void __net_exit pedit_exit_net(struct net *net)
	253	{
	254	struct tc_action_net *tn = net_generic(net, pedit_net_id);
	255
	256	tc_action_net_exit(tn);
	257	}
	258
	259	static struct pernet_operations pedit_net_ops = {
	260	.init = pedit_init_net,
	261	.exit = pedit_exit_net,
	262	.id = &pedit_net_id,
	263	.size = sizeof(struct tc_action_net),
1da177e4 LT	264	};
	265
	266	MODULE_AUTHOR("Jamal Hadi Salim(2002-4)");
	267	MODULE_DESCRIPTION("Generic Packet Editor actions");
	268	MODULE_LICENSE("GPL");
	269
e9ce1cd3	270	static int __init pedit_init_module(void)
1da177e4	271	{
ddf97ccd	272	return tcf_register_action(&act_pedit_ops, &pedit_net_ops);
1da177e4 LT	273	}
1da177e4 LT	274
e9ce1cd3	275	static void __exit pedit_cleanup_module(void)
1da177e4	276	{
ddf97ccd	277	tcf_unregister_action(&act_pedit_ops, &pedit_net_ops);
1da177e4 LT	278	}
	279
	280	module_init(pedit_init_module);
	281	module_exit(pedit_cleanup_module);
	282