[deliverable/linux.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 struct tc_action_ops act_pedit_ops;

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,
				      &act_pedit_ops, 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 = to_pedit(a);
	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 = to_pedit(a);
	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);

	tcf_lastuse_update(&p->tcf_tm);

	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 = to_pedit(a);
	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;

	tcf_tm_dump(&t, &p->tcf_tm);
	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,
			    const struct tc_action_ops *ops)
{
	struct tc_action_net *tn = net_generic(net, pedit_net_id);

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

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,
	.size		=	sizeof(struct tcf_pedit),
};

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	28	static int pedit_net_id;
a85a970a	29	static struct tc_action_ops act_pedit_ops;
ddf97ccd	30
53b2bf3f	31	static const struct nla_policy pedit_policy[TCA_PEDIT_MAX + 1] = {
53f7e35f	32	[TCA_PEDIT_PARMS] = { .len = sizeof(struct tc_pedit) },
53b2bf3f PM	33	};
53b2bf3f PM	34
c1b52739	35	static int tcf_pedit_init(struct net net, struct nlattr nla,
a85a970a	36	struct nlattr est, struct tc_action *a,
c1b52739	37	int ovr, int bind)
1da177e4	38	{
ddf97ccd	39	struct tc_action_net *tn = net_generic(net, pedit_net_id);
7ba699c6	40	struct nlattr *tb[TCA_PEDIT_MAX + 1];
1da177e4	41	struct tc_pedit *parm;
cee63723	42	int ret = 0, err;
1da177e4 LT	43	struct tcf_pedit *p;
	44	struct tc_pedit_key *keys = NULL;
	45	int ksize;
	46
cee63723	47	if (nla == NULL)
1da177e4 LT	48	return -EINVAL;
1da177e4 LT	49
53b2bf3f	50	err = nla_parse_nested(tb, TCA_PEDIT_MAX, nla, pedit_policy);
cee63723 PM	51	if (err < 0)
	52	return err;
	53
53b2bf3f	54	if (tb[TCA_PEDIT_PARMS] == NULL)
1da177e4	55	return -EINVAL;
7ba699c6	56	parm = nla_data(tb[TCA_PEDIT_PARMS]);
1da177e4	57	ksize = parm->nkeys * sizeof(struct tc_pedit_key);
7ba699c6	58	if (nla_len(tb[TCA_PEDIT_PARMS]) < sizeof(*parm) + ksize)
1da177e4 LT	59	return -EINVAL;
1da177e4 LT	60
ddf97ccd	61	if (!tcf_hash_check(tn, parm->index, a, bind)) {
1da177e4 LT	62	if (!parm->nkeys)
1da177e4 LT	63	return -EINVAL;
ddf97ccd	64	ret = tcf_hash_create(tn, parm->index, est, a,
a85a970a	65	&act_pedit_ops, bind, false);
86062033 WC	66	if (ret)
86062033 WC	67	return ret;
a85a970a	68	p = to_pedit(*a);
1da177e4 LT	69	keys = kmalloc(ksize, GFP_KERNEL);
1da177e4 LT	70	if (keys == NULL) {
a85a970a	71	tcf_hash_cleanup(*a, est);
1da177e4 LT	72	return -ENOMEM;
	73	}
	74	ret = ACT_P_CREATED;
	75	} else {
1a29321e JHS	76	if (bind)
1a29321e JHS	77	return 0;
a85a970a	78	tcf_hash_release(*a, bind);
1a29321e	79	if (!ovr)
1da177e4	80	return -EEXIST;
a85a970a	81	p = to_pedit(*a);
e9ce1cd3	82	if (p->tcfp_nkeys && p->tcfp_nkeys != parm->nkeys) {
1da177e4 LT	83	keys = kmalloc(ksize, GFP_KERNEL);
	84	if (keys == NULL)
	85	return -ENOMEM;
	86	}
	87	}
	88
e9ce1cd3 DM	89	spin_lock_bh(&p->tcf_lock);
	90	p->tcfp_flags = parm->flags;
	91	p->tcf_action = parm->action;
1da177e4	92	if (keys) {
e9ce1cd3 DM	93	kfree(p->tcfp_keys);
	94	p->tcfp_keys = keys;
	95	p->tcfp_nkeys = parm->nkeys;
1da177e4	96	}
e9ce1cd3 DM	97	memcpy(p->tcfp_keys, parm->keys, ksize);
e9ce1cd3 DM	98	spin_unlock_bh(&p->tcf_lock);
1da177e4	99	if (ret == ACT_P_CREATED)
a85a970a	100	tcf_hash_insert(tn, *a);
1da177e4 LT	101	return ret;
	102	}
	103
a5b5c958	104	static void tcf_pedit_cleanup(struct tc_action *a, int bind)
1da177e4	105	{
a85a970a	106	struct tcf_pedit *p = to_pedit(a);
a5b5c958 WC	107	struct tc_pedit_key *keys = p->tcfp_keys;
a5b5c958 WC	108	kfree(keys);
1da177e4 LT	109	}
1da177e4 LT	110
dc7f9f6e	111	static int tcf_pedit(struct sk_buff skb, const struct tc_action a,
e9ce1cd3	112	struct tcf_result *res)
1da177e4	113	{
a85a970a	114	struct tcf_pedit *p = to_pedit(a);
4749c3ef	115	int i;
db2c2417	116	unsigned int off;
1da177e4	117
14bbd6a5	118	if (skb_unclone(skb, GFP_ATOMIC))
cc7ec456	119	return p->tcf_action;
1da177e4	120
db2c2417	121	off = skb_network_offset(skb);
1da177e4	122
e9ce1cd3	123	spin_lock(&p->tcf_lock);
1da177e4	124
9c4a4e48	125	tcf_lastuse_update(&p->tcf_tm);
1da177e4	126
e9ce1cd3 DM	127	if (p->tcfp_nkeys > 0) {
e9ce1cd3 DM	128	struct tc_pedit_key *tkey = p->tcfp_keys;
1da177e4	129
e9ce1cd3	130	for (i = p->tcfp_nkeys; i > 0; i--, tkey++) {
db2c2417	131	u32 *ptr, _data;
1da177e4 LT	132	int offset = tkey->off;
	133
	134	if (tkey->offmask) {
db2c2417 CG	135	char *d, _d;
	136
	137	d = skb_header_pointer(skb, off + tkey->at, 1,
	138	&_d);
	139	if (!d)
1da177e4	140	goto bad;
db2c2417	141	offset += (*d & tkey->offmask) >> tkey->shift;
1da177e4 LT	142	}
	143
	144	if (offset % 4) {
6ff9c364	145	pr_info("tc filter pedit"
6ff9c364	146	" offset must be on 32 bit boundaries\n");
1da177e4 LT	147	goto bad;
1da177e4 LT	148	}
75202e76	149	if (offset > 0 && offset > skb->len) {
6ff9c364	150	pr_info("tc filter pedit"
25985edc	151	" offset %d can't exceed pkt length %d\n",
1da177e4 LT	152	offset, skb->len);
	153	goto bad;
	154	}
	155
db2c2417 CG	156	ptr = skb_header_pointer(skb, off + offset, 4, &_data);
	157	if (!ptr)
	158	goto bad;
1da177e4 LT	159	/* just do it, baby */
1da177e4 LT	160	ptr = ((ptr & tkey->mask) ^ tkey->val);
db2c2417 CG	161	if (ptr == &_data)
db2c2417 CG	162	skb_store_bits(skb, off + offset, ptr, 4);
1da177e4	163	}
10297b99	164
1da177e4	165	goto done;
6ff9c364	166	} else
6ff9c364	167	WARN(1, "pedit BUG: index %d\n", p->tcf_index);
1da177e4 LT	168
1da177e4 LT	169	bad:
e9ce1cd3	170	p->tcf_qstats.overlimits++;
1da177e4	171	done:
bfe0d029	172	bstats_update(&p->tcf_bstats, skb);
e9ce1cd3 DM	173	spin_unlock(&p->tcf_lock);
e9ce1cd3 DM	174	return p->tcf_action;
1da177e4 LT	175	}
1da177e4 LT	176
e9ce1cd3 DM	177	static int tcf_pedit_dump(struct sk_buff skb, struct tc_action a,
e9ce1cd3 DM	178	int bind, int ref)
1da177e4	179	{
27a884dc	180	unsigned char *b = skb_tail_pointer(skb);
a85a970a	181	struct tcf_pedit *p = to_pedit(a);
1da177e4	182	struct tc_pedit *opt;
1da177e4	183	struct tcf_t t;
10297b99 YH	184	int s;
10297b99 YH	185
e9ce1cd3	186	s = sizeof(opt) + p->tcfp_nkeys sizeof(struct tc_pedit_key);
1da177e4 LT	187
1da177e4 LT	188	/* netlink spinlocks held above us - must use ATOMIC */
0da974f4	189	opt = kzalloc(s, GFP_ATOMIC);
e9ce1cd3	190	if (unlikely(!opt))
1da177e4	191	return -ENOBUFS;
1da177e4	192
e9ce1cd3 DM	193	memcpy(opt->keys, p->tcfp_keys,
	194	p->tcfp_nkeys * sizeof(struct tc_pedit_key));
	195	opt->index = p->tcf_index;
	196	opt->nkeys = p->tcfp_nkeys;
	197	opt->flags = p->tcfp_flags;
	198	opt->action = p->tcf_action;
	199	opt->refcnt = p->tcf_refcnt - ref;
	200	opt->bindcnt = p->tcf_bindcnt - bind;
1da177e4	201
1b34ec43 DM	202	if (nla_put(skb, TCA_PEDIT_PARMS, s, opt))
1b34ec43 DM	203	goto nla_put_failure;
48d8ee16 JHS	204
48d8ee16 JHS	205	tcf_tm_dump(&t, &p->tcf_tm);
9854518e	206	if (nla_put_64bit(skb, TCA_PEDIT_TM, sizeof(t), &t, TCA_PEDIT_PAD))
1b34ec43	207	goto nla_put_failure;
48d8ee16	208
541673c8	209	kfree(opt);
1da177e4 LT	210	return skb->len;
1da177e4 LT	211
7ba699c6	212	nla_put_failure:
dc5fc579	213	nlmsg_trim(skb, b);
541673c8	214	kfree(opt);
1da177e4 LT	215	return -1;
	216	}
	217
ddf97ccd WC	218	static int tcf_pedit_walker(struct net net, struct sk_buff skb,
ddf97ccd WC	219	struct netlink_callback *cb, int type,
a85a970a	220	const struct tc_action_ops *ops)
ddf97ccd WC	221	{
	222	struct tc_action_net *tn = net_generic(net, pedit_net_id);
	223
a85a970a	224	return tcf_generic_walker(tn, skb, cb, type, ops);
ddf97ccd WC	225	}
ddf97ccd WC	226
a85a970a	227	static int tcf_pedit_search(struct net net, struct tc_action *a, u32 index)
ddf97ccd WC	228	{
	229	struct tc_action_net *tn = net_generic(net, pedit_net_id);
	230
	231	return tcf_hash_search(tn, a, index);
	232	}
	233
e9ce1cd3	234	static struct tc_action_ops act_pedit_ops = {
1da177e4 LT	235	.kind = "pedit",
1da177e4 LT	236	.type = TCA_ACT_PEDIT,
1da177e4 LT	237	.owner = THIS_MODULE,
	238	.act = tcf_pedit,
	239	.dump = tcf_pedit_dump,
	240	.cleanup = tcf_pedit_cleanup,
1da177e4	241	.init = tcf_pedit_init,
ddf97ccd WC	242	.walk = tcf_pedit_walker,
ddf97ccd WC	243	.lookup = tcf_pedit_search,
a85a970a	244	.size = sizeof(struct tcf_pedit),
ddf97ccd WC	245	};
	246
	247	static __net_init int pedit_init_net(struct net *net)
	248	{
	249	struct tc_action_net *tn = net_generic(net, pedit_net_id);
	250
	251	return tc_action_net_init(tn, &act_pedit_ops, PEDIT_TAB_MASK);
	252	}
	253
	254	static void __net_exit pedit_exit_net(struct net *net)
	255	{
	256	struct tc_action_net *tn = net_generic(net, pedit_net_id);
	257
	258	tc_action_net_exit(tn);
	259	}
	260
	261	static struct pernet_operations pedit_net_ops = {
	262	.init = pedit_init_net,
	263	.exit = pedit_exit_net,
	264	.id = &pedit_net_id,
	265	.size = sizeof(struct tc_action_net),
1da177e4 LT	266	};
	267
	268	MODULE_AUTHOR("Jamal Hadi Salim(2002-4)");
	269	MODULE_DESCRIPTION("Generic Packet Editor actions");
	270	MODULE_LICENSE("GPL");
	271
e9ce1cd3	272	static int __init pedit_init_module(void)
1da177e4	273	{
ddf97ccd	274	return tcf_register_action(&act_pedit_ops, &pedit_net_ops);
1da177e4 LT	275	}
1da177e4 LT	276
e9ce1cd3	277	static void __exit pedit_cleanup_module(void)
1da177e4	278	{
ddf97ccd	279	tcf_unregister_action(&act_pedit_ops, &pedit_net_ops);
1da177e4 LT	280	}
	281
	282	module_init(pedit_init_module);
	283	module_exit(pedit_cleanup_module);
	284