[GitHub/mt8127/android_kernel_alcatel_ttab.git] / net / sched / act_pedit.c

/*
 * net/sched/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 struct tcf_common *tcf_pedit_ht[PEDIT_TAB_MASK + 1];
static u32 pedit_idx_gen;
static DEFINE_RWLOCK(pedit_lock);

static struct tcf_hashinfo pedit_hash_info = {
	.htab	=	tcf_pedit_ht,
	.hmask	=	PEDIT_TAB_MASK,
	.lock	=	&pedit_lock,
};

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 nlattr *tb[TCA_PEDIT_MAX + 1];
	struct tc_pedit *parm;
	int ret = 0, err;
	struct tcf_pedit *p;
	struct tcf_common *pc;
	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;

	pc = tcf_hash_check(parm->index, a, bind, &pedit_hash_info);
	if (!pc) {
		if (!parm->nkeys)
			return -EINVAL;
		pc = tcf_hash_create(parm->index, est, a, sizeof(*p), bind,
				     &pedit_idx_gen, &pedit_hash_info);
		if (IS_ERR(pc))
			return PTR_ERR(pc);
		p = to_pedit(pc);
		keys = kmalloc(ksize, GFP_KERNEL);
		if (keys == NULL) {
			if (est)
				gen_kill_estimator(&pc->tcfc_bstats,
						   &pc->tcfc_rate_est);
			kfree_rcu(pc, tcfc_rcu);
			return -ENOMEM;
		}
		ret = ACT_P_CREATED;
	} else {
		p = to_pedit(pc);
		if (!ovr) {
			tcf_hash_release(pc, bind, &pedit_hash_info);
			return -EEXIST;
		}
		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(pc, &pedit_hash_info);
	return ret;
}

static int tcf_pedit_cleanup(struct tc_action *a, int bind)
{
	struct tcf_pedit *p = a->priv;

	if (p) {
		struct tc_pedit_key *keys = p->tcfp_keys;
		if (tcf_hash_release(&p->common, bind, &pedit_hash_info)) {
			kfree(keys);
			return 1;
		}
	}
	return 0;
}

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, munged = 0;
	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);
			munged++;
		}

		if (munged)
			skb->tc_verd = SET_TC_MUNGED(skb->tc_verd);
		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(skb, TCA_PEDIT_TM, sizeof(t), &t))
		goto nla_put_failure;
	kfree(opt);
	return skb->len;

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

static struct tc_action_ops act_pedit_ops = {
	.kind		=	"pedit",
	.hinfo		=	&pedit_hash_info,
	.type		=	TCA_ACT_PEDIT,
	.capab		=	TCA_CAP_NONE,
	.owner		=	THIS_MODULE,
	.act		=	tcf_pedit,
	.dump		=	tcf_pedit_dump,
	.cleanup	=	tcf_pedit_cleanup,
	.lookup		=	tcf_hash_search,
	.init		=	tcf_pedit_init,
	.walk		=	tcf_generic_walker
};

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);
}

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

module_init(pedit_init_module);
module_exit(pedit_cleanup_module);
Commit	Line	Data
1da177e4 LT	1	/*
	2	* net/sched/pedit.c Generic packet editor
	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 DM	26	#define PEDIT_TAB_MASK 15
	27	static struct tcf_common *tcf_pedit_ht[PEDIT_TAB_MASK + 1];
	28	static u32 pedit_idx_gen;
1da177e4 LT	29	static DEFINE_RWLOCK(pedit_lock);
1da177e4 LT	30
e9ce1cd3 DM	31	static struct tcf_hashinfo pedit_hash_info = {
	32	.htab = tcf_pedit_ht,
	33	.hmask = PEDIT_TAB_MASK,
	34	.lock = &pedit_lock,
	35	};
1da177e4	36
53b2bf3f	37	static const struct nla_policy pedit_policy[TCA_PEDIT_MAX + 1] = {
53f7e35f	38	[TCA_PEDIT_PARMS] = { .len = sizeof(struct tc_pedit) },
53b2bf3f PM	39	};
53b2bf3f PM	40
c1b52739 BL	41	static int tcf_pedit_init(struct net net, struct nlattr nla,
	42	struct nlattr est, struct tc_action a,
	43	int ovr, int bind)
1da177e4	44	{
7ba699c6	45	struct nlattr *tb[TCA_PEDIT_MAX + 1];
1da177e4	46	struct tc_pedit *parm;
cee63723	47	int ret = 0, err;
1da177e4	48	struct tcf_pedit *p;
e9ce1cd3	49	struct tcf_common *pc;
1da177e4 LT	50	struct tc_pedit_key *keys = NULL;
	51	int ksize;
	52
cee63723	53	if (nla == NULL)
1da177e4 LT	54	return -EINVAL;
1da177e4 LT	55
53b2bf3f	56	err = nla_parse_nested(tb, TCA_PEDIT_MAX, nla, pedit_policy);
cee63723 PM	57	if (err < 0)
	58	return err;
	59
53b2bf3f	60	if (tb[TCA_PEDIT_PARMS] == NULL)
1da177e4	61	return -EINVAL;
7ba699c6	62	parm = nla_data(tb[TCA_PEDIT_PARMS]);
1da177e4	63	ksize = parm->nkeys * sizeof(struct tc_pedit_key);
7ba699c6	64	if (nla_len(tb[TCA_PEDIT_PARMS]) < sizeof(*parm) + ksize)
1da177e4 LT	65	return -EINVAL;
1da177e4 LT	66
e9ce1cd3 DM	67	pc = tcf_hash_check(parm->index, a, bind, &pedit_hash_info);
e9ce1cd3 DM	68	if (!pc) {
1da177e4 LT	69	if (!parm->nkeys)
1da177e4 LT	70	return -EINVAL;
e9ce1cd3 DM	71	pc = tcf_hash_create(parm->index, est, a, sizeof(*p), bind,
e9ce1cd3 DM	72	&pedit_idx_gen, &pedit_hash_info);
0e991ec6	73	if (IS_ERR(pc))
cc7ec456	74	return PTR_ERR(pc);
e9ce1cd3	75	p = to_pedit(pc);
1da177e4 LT	76	keys = kmalloc(ksize, GFP_KERNEL);
1da177e4 LT	77	if (keys == NULL) {
47fd92f5 HS	78	if (est)
	79	gen_kill_estimator(&pc->tcfc_bstats,
	80	&pc->tcfc_rate_est);
	81	kfree_rcu(pc, tcfc_rcu);
1da177e4 LT	82	return -ENOMEM;
	83	}
	84	ret = ACT_P_CREATED;
	85	} else {
e9ce1cd3	86	p = to_pedit(pc);
1da177e4	87	if (!ovr) {
e9ce1cd3	88	tcf_hash_release(pc, bind, &pedit_hash_info);
1da177e4 LT	89	return -EEXIST;
1da177e4 LT	90	}
e9ce1cd3	91	if (p->tcfp_nkeys && p->tcfp_nkeys != parm->nkeys) {
1da177e4 LT	92	keys = kmalloc(ksize, GFP_KERNEL);
	93	if (keys == NULL)
	94	return -ENOMEM;
	95	}
	96	}
	97
e9ce1cd3 DM	98	spin_lock_bh(&p->tcf_lock);
	99	p->tcfp_flags = parm->flags;
	100	p->tcf_action = parm->action;
1da177e4	101	if (keys) {
e9ce1cd3 DM	102	kfree(p->tcfp_keys);
	103	p->tcfp_keys = keys;
	104	p->tcfp_nkeys = parm->nkeys;
1da177e4	105	}
e9ce1cd3 DM	106	memcpy(p->tcfp_keys, parm->keys, ksize);
e9ce1cd3 DM	107	spin_unlock_bh(&p->tcf_lock);
1da177e4	108	if (ret == ACT_P_CREATED)
e9ce1cd3	109	tcf_hash_insert(pc, &pedit_hash_info);
1da177e4 LT	110	return ret;
	111	}
	112
e9ce1cd3	113	static int tcf_pedit_cleanup(struct tc_action *a, int bind)
1da177e4	114	{
e9ce1cd3	115	struct tcf_pedit *p = a->priv;
1da177e4	116
e9ce1cd3 DM	117	if (p) {
	118	struct tc_pedit_key *keys = p->tcfp_keys;
	119	if (tcf_hash_release(&p->common, bind, &pedit_hash_info)) {
1da177e4 LT	120	kfree(keys);
	121	return 1;
	122	}
	123	}
	124	return 0;
	125	}
	126
dc7f9f6e	127	static int tcf_pedit(struct sk_buff skb, const struct tc_action a,
e9ce1cd3	128	struct tcf_result *res)
1da177e4	129	{
e9ce1cd3	130	struct tcf_pedit *p = a->priv;
1da177e4	131	int i, munged = 0;
db2c2417	132	unsigned int off;
1da177e4	133
14bbd6a5	134	if (skb_unclone(skb, GFP_ATOMIC))
cc7ec456	135	return p->tcf_action;
1da177e4	136
db2c2417	137	off = skb_network_offset(skb);
1da177e4	138
e9ce1cd3	139	spin_lock(&p->tcf_lock);
1da177e4	140
e9ce1cd3	141	p->tcf_tm.lastuse = jiffies;
1da177e4	142
e9ce1cd3 DM	143	if (p->tcfp_nkeys > 0) {
e9ce1cd3 DM	144	struct tc_pedit_key *tkey = p->tcfp_keys;
1da177e4	145
e9ce1cd3	146	for (i = p->tcfp_nkeys; i > 0; i--, tkey++) {
db2c2417	147	u32 *ptr, _data;
1da177e4 LT	148	int offset = tkey->off;
	149
	150	if (tkey->offmask) {
db2c2417 CG	151	char *d, _d;
	152
	153	d = skb_header_pointer(skb, off + tkey->at, 1,
	154	&_d);
	155	if (!d)
1da177e4	156	goto bad;
db2c2417	157	offset += (*d & tkey->offmask) >> tkey->shift;
1da177e4 LT	158	}
	159
	160	if (offset % 4) {
6ff9c364	161	pr_info("tc filter pedit"
6ff9c364	162	" offset must be on 32 bit boundaries\n");
1da177e4 LT	163	goto bad;
1da177e4 LT	164	}
75202e76	165	if (offset > 0 && offset > skb->len) {
6ff9c364	166	pr_info("tc filter pedit"
25985edc	167	" offset %d can't exceed pkt length %d\n",
1da177e4 LT	168	offset, skb->len);
	169	goto bad;
	170	}
	171
db2c2417 CG	172	ptr = skb_header_pointer(skb, off + offset, 4, &_data);
	173	if (!ptr)
	174	goto bad;
1da177e4 LT	175	/* just do it, baby */
1da177e4 LT	176	ptr = ((ptr & tkey->mask) ^ tkey->val);
db2c2417 CG	177	if (ptr == &_data)
db2c2417 CG	178	skb_store_bits(skb, off + offset, ptr, 4);
1da177e4 LT	179	munged++;
1da177e4 LT	180	}
10297b99	181
1da177e4 LT	182	if (munged)
	183	skb->tc_verd = SET_TC_MUNGED(skb->tc_verd);
	184	goto done;
6ff9c364	185	} else
6ff9c364	186	WARN(1, "pedit BUG: index %d\n", p->tcf_index);
1da177e4 LT	187
1da177e4 LT	188	bad:
e9ce1cd3	189	p->tcf_qstats.overlimits++;
1da177e4	190	done:
bfe0d029	191	bstats_update(&p->tcf_bstats, skb);
e9ce1cd3 DM	192	spin_unlock(&p->tcf_lock);
e9ce1cd3 DM	193	return p->tcf_action;
1da177e4 LT	194	}
1da177e4 LT	195
e9ce1cd3 DM	196	static int tcf_pedit_dump(struct sk_buff skb, struct tc_action a,
e9ce1cd3 DM	197	int bind, int ref)
1da177e4	198	{
27a884dc	199	unsigned char *b = skb_tail_pointer(skb);
e9ce1cd3	200	struct tcf_pedit *p = a->priv;
1da177e4	201	struct tc_pedit *opt;
1da177e4	202	struct tcf_t t;
10297b99 YH	203	int s;
10297b99 YH	204
e9ce1cd3	205	s = sizeof(opt) + p->tcfp_nkeys sizeof(struct tc_pedit_key);
1da177e4 LT	206
1da177e4 LT	207	/* netlink spinlocks held above us - must use ATOMIC */
0da974f4	208	opt = kzalloc(s, GFP_ATOMIC);
e9ce1cd3	209	if (unlikely(!opt))
1da177e4	210	return -ENOBUFS;
1da177e4	211
e9ce1cd3 DM	212	memcpy(opt->keys, p->tcfp_keys,
	213	p->tcfp_nkeys * sizeof(struct tc_pedit_key));
	214	opt->index = p->tcf_index;
	215	opt->nkeys = p->tcfp_nkeys;
	216	opt->flags = p->tcfp_flags;
	217	opt->action = p->tcf_action;
	218	opt->refcnt = p->tcf_refcnt - ref;
	219	opt->bindcnt = p->tcf_bindcnt - bind;
1da177e4	220
1b34ec43 DM	221	if (nla_put(skb, TCA_PEDIT_PARMS, s, opt))
1b34ec43 DM	222	goto nla_put_failure;
e9ce1cd3 DM	223	t.install = jiffies_to_clock_t(jiffies - p->tcf_tm.install);
	224	t.lastuse = jiffies_to_clock_t(jiffies - p->tcf_tm.lastuse);
	225	t.expires = jiffies_to_clock_t(p->tcf_tm.expires);
1b34ec43 DM	226	if (nla_put(skb, TCA_PEDIT_TM, sizeof(t), &t))
1b34ec43 DM	227	goto nla_put_failure;
541673c8	228	kfree(opt);
1da177e4 LT	229	return skb->len;
1da177e4 LT	230
7ba699c6	231	nla_put_failure:
dc5fc579	232	nlmsg_trim(skb, b);
541673c8	233	kfree(opt);
1da177e4 LT	234	return -1;
	235	}
	236
e9ce1cd3	237	static struct tc_action_ops act_pedit_ops = {
1da177e4	238	.kind = "pedit",
e9ce1cd3	239	.hinfo = &pedit_hash_info,
1da177e4 LT	240	.type = TCA_ACT_PEDIT,
	241	.capab = TCA_CAP_NONE,
	242	.owner = THIS_MODULE,
	243	.act = tcf_pedit,
	244	.dump = tcf_pedit_dump,
	245	.cleanup = tcf_pedit_cleanup,
	246	.lookup = tcf_hash_search,
	247	.init = tcf_pedit_init,
	248	.walk = tcf_generic_walker
	249	};
	250
	251	MODULE_AUTHOR("Jamal Hadi Salim(2002-4)");
	252	MODULE_DESCRIPTION("Generic Packet Editor actions");
	253	MODULE_LICENSE("GPL");
	254
e9ce1cd3	255	static int __init pedit_init_module(void)
1da177e4 LT	256	{
	257	return tcf_register_action(&act_pedit_ops);
	258	}
	259
e9ce1cd3	260	static void __exit pedit_cleanup_module(void)
1da177e4 LT	261	{
	262	tcf_unregister_action(&act_pedit_ops);
	263	}
	264
	265	module_init(pedit_init_module);
	266	module_exit(pedit_cleanup_module);
	267