[linux-2.6-block.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 <asm/uaccess.h>
#include <asm/system.h>
#include <asm/bitops.h>
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/string.h>
#include <linux/mm.h>
#include <linux/socket.h>
#include <linux/sockios.h>
#include <linux/in.h>
#include <linux/errno.h>
#include <linux/interrupt.h>
#include <linux/netdevice.h>
#include <linux/skbuff.h>
#include <linux/rtnetlink.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/proc_fs.h>
#include <net/netlink.h>
#include <net/sock.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 int tcf_pedit_init(struct rtattr *rta, struct rtattr *est,
			  struct tc_action *a, int ovr, int bind)
{
	struct rtattr *tb[TCA_PEDIT_MAX];
	struct tc_pedit *parm;
	int ret = 0;
	struct tcf_pedit *p;
	struct tcf_common *pc;
	struct tc_pedit_key *keys = NULL;
	int ksize;

	if (rta == NULL || rtattr_parse_nested(tb, TCA_PEDIT_MAX, rta) < 0)
		return -EINVAL;

	if (tb[TCA_PEDIT_PARMS - 1] == NULL ||
	    RTA_PAYLOAD(tb[TCA_PEDIT_PARMS-1]) < sizeof(*parm))
		return -EINVAL;
	parm = RTA_DATA(tb[TCA_PEDIT_PARMS-1]);
	ksize = parm->nkeys * sizeof(struct tc_pedit_key);
	if (RTA_PAYLOAD(tb[TCA_PEDIT_PARMS-1]) < 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 (unlikely(!pc))
			return -ENOMEM;
		p = to_pedit(pc);
		keys = kmalloc(ksize, GFP_KERNEL);
		if (keys == NULL) {
			kfree(pc);
			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, struct tc_action *a,
		     struct tcf_result *res)
{
	struct tcf_pedit *p = a->priv;
	int i, munged = 0;
	u8 *pptr;

	if (!(skb->tc_verd & TC_OK2MUNGE)) {
		/* should we set skb->cloned? */
		if (pskb_expand_head(skb, 0, 0, GFP_ATOMIC)) {
			return p->tcf_action;
		}
	}

	pptr = skb_network_header(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;
			int offset = tkey->off;

			if (tkey->offmask) {
				if (skb->len > tkey->at) {
					 char *j = pptr + tkey->at;
					 offset += ((*j & tkey->offmask) >>
						   tkey->shift);
				} else {
					goto bad;
				}
			}

			if (offset % 4) {
				printk("offset must be on 32 bit boundaries\n");
				goto bad;
			}
			if (offset > 0 && offset > skb->len) {
				printk("offset %d cant exceed pkt length %d\n",
				       offset, skb->len);
				goto bad;
			}

			ptr = (u32 *)(pptr+offset);
			/* just do it, baby */
			*ptr = ((*ptr & tkey->mask) ^ tkey->val);
			munged++;
		}

		if (munged)
			skb->tc_verd = SET_TC_MUNGED(skb->tc_verd);
		goto done;
	} else {
		printk("pedit BUG: index %d\n", p->tcf_index);
	}

bad:
	p->tcf_qstats.overlimits++;
done:
	p->tcf_bstats.bytes += skb->len;
	p->tcf_bstats.packets++;
	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;

	RTA_PUT(skb, TCA_PEDIT_PARMS, s, opt);
	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);
	RTA_PUT(skb, TCA_PEDIT_TM, sizeof(t), &t);
	kfree(opt);
	return skb->len;

rtattr_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
	12	#include <asm/uaccess.h>
	13	#include <asm/system.h>
	14	#include <asm/bitops.h>
1da177e4 LT	15	#include <linux/types.h>
1da177e4 LT	16	#include <linux/kernel.h>
1da177e4 LT	17	#include <linux/string.h>
	18	#include <linux/mm.h>
	19	#include <linux/socket.h>
	20	#include <linux/sockios.h>
	21	#include <linux/in.h>
	22	#include <linux/errno.h>
	23	#include <linux/interrupt.h>
	24	#include <linux/netdevice.h>
	25	#include <linux/skbuff.h>
	26	#include <linux/rtnetlink.h>
	27	#include <linux/module.h>
	28	#include <linux/init.h>
	29	#include <linux/proc_fs.h>
dc5fc579	30	#include <net/netlink.h>
1da177e4 LT	31	#include <net/sock.h>
	32	#include <net/pkt_sched.h>
	33	#include <linux/tc_act/tc_pedit.h>
	34	#include <net/tc_act/tc_pedit.h>
	35
e9ce1cd3 DM	36	#define PEDIT_TAB_MASK 15
	37	static struct tcf_common *tcf_pedit_ht[PEDIT_TAB_MASK + 1];
	38	static u32 pedit_idx_gen;
1da177e4 LT	39	static DEFINE_RWLOCK(pedit_lock);
1da177e4 LT	40
e9ce1cd3 DM	41	static struct tcf_hashinfo pedit_hash_info = {
	42	.htab = tcf_pedit_ht,
	43	.hmask = PEDIT_TAB_MASK,
	44	.lock = &pedit_lock,
	45	};
1da177e4	46
e9ce1cd3 DM	47	static int tcf_pedit_init(struct rtattr rta, struct rtattr est,
e9ce1cd3 DM	48	struct tc_action *a, int ovr, int bind)
1da177e4 LT	49	{
	50	struct rtattr *tb[TCA_PEDIT_MAX];
	51	struct tc_pedit *parm;
	52	int ret = 0;
	53	struct tcf_pedit *p;
e9ce1cd3	54	struct tcf_common *pc;
1da177e4 LT	55	struct tc_pedit_key *keys = NULL;
	56	int ksize;
	57
	58	if (rta == NULL \|\| rtattr_parse_nested(tb, TCA_PEDIT_MAX, rta) < 0)
	59	return -EINVAL;
	60
	61	if (tb[TCA_PEDIT_PARMS - 1] == NULL \|\|
	62	RTA_PAYLOAD(tb[TCA_PEDIT_PARMS-1]) < sizeof(*parm))
	63	return -EINVAL;
	64	parm = RTA_DATA(tb[TCA_PEDIT_PARMS-1]);
	65	ksize = parm->nkeys * sizeof(struct tc_pedit_key);
	66	if (RTA_PAYLOAD(tb[TCA_PEDIT_PARMS-1]) < sizeof(*parm) + ksize)
	67	return -EINVAL;
	68
e9ce1cd3 DM	69	pc = tcf_hash_check(parm->index, a, bind, &pedit_hash_info);
e9ce1cd3 DM	70	if (!pc) {
1da177e4 LT	71	if (!parm->nkeys)
1da177e4 LT	72	return -EINVAL;
e9ce1cd3 DM	73	pc = tcf_hash_create(parm->index, est, a, sizeof(*p), bind,
	74	&pedit_idx_gen, &pedit_hash_info);
	75	if (unlikely(!pc))
1da177e4	76	return -ENOMEM;
e9ce1cd3	77	p = to_pedit(pc);
1da177e4 LT	78	keys = kmalloc(ksize, GFP_KERNEL);
1da177e4 LT	79	if (keys == NULL) {
e9ce1cd3	80	kfree(pc);
1da177e4 LT	81	return -ENOMEM;
	82	}
	83	ret = ACT_P_CREATED;
	84	} else {
e9ce1cd3	85	p = to_pedit(pc);
1da177e4	86	if (!ovr) {
e9ce1cd3	87	tcf_hash_release(pc, bind, &pedit_hash_info);
1da177e4 LT	88	return -EEXIST;
1da177e4 LT	89	}
e9ce1cd3	90	if (p->tcfp_nkeys && p->tcfp_nkeys != parm->nkeys) {
1da177e4 LT	91	keys = kmalloc(ksize, GFP_KERNEL);
	92	if (keys == NULL)
	93	return -ENOMEM;
	94	}
	95	}
	96
e9ce1cd3 DM	97	spin_lock_bh(&p->tcf_lock);
	98	p->tcfp_flags = parm->flags;
	99	p->tcf_action = parm->action;
1da177e4	100	if (keys) {
e9ce1cd3 DM	101	kfree(p->tcfp_keys);
	102	p->tcfp_keys = keys;
	103	p->tcfp_nkeys = parm->nkeys;
1da177e4	104	}
e9ce1cd3 DM	105	memcpy(p->tcfp_keys, parm->keys, ksize);
e9ce1cd3 DM	106	spin_unlock_bh(&p->tcf_lock);
1da177e4	107	if (ret == ACT_P_CREATED)
e9ce1cd3	108	tcf_hash_insert(pc, &pedit_hash_info);
1da177e4 LT	109	return ret;
	110	}
	111
e9ce1cd3	112	static int tcf_pedit_cleanup(struct tc_action *a, int bind)
1da177e4	113	{
e9ce1cd3	114	struct tcf_pedit *p = a->priv;
1da177e4	115
e9ce1cd3 DM	116	if (p) {
	117	struct tc_pedit_key *keys = p->tcfp_keys;
	118	if (tcf_hash_release(&p->common, bind, &pedit_hash_info)) {
1da177e4 LT	119	kfree(keys);
	120	return 1;
	121	}
	122	}
	123	return 0;
	124	}
	125
e9ce1cd3 DM	126	static int tcf_pedit(struct sk_buff skb, struct tc_action a,
e9ce1cd3 DM	127	struct tcf_result *res)
1da177e4	128	{
e9ce1cd3	129	struct tcf_pedit *p = a->priv;
1da177e4 LT	130	int i, munged = 0;
	131	u8 *pptr;
	132
	133	if (!(skb->tc_verd & TC_OK2MUNGE)) {
	134	/* should we set skb->cloned? */
	135	if (pskb_expand_head(skb, 0, 0, GFP_ATOMIC)) {
e9ce1cd3	136	return p->tcf_action;
1da177e4 LT	137	}
	138	}
	139
d56f90a7	140	pptr = skb_network_header(skb);
1da177e4	141
e9ce1cd3	142	spin_lock(&p->tcf_lock);
1da177e4	143
e9ce1cd3	144	p->tcf_tm.lastuse = jiffies;
1da177e4	145
e9ce1cd3 DM	146	if (p->tcfp_nkeys > 0) {
e9ce1cd3 DM	147	struct tc_pedit_key *tkey = p->tcfp_keys;
1da177e4	148
e9ce1cd3	149	for (i = p->tcfp_nkeys; i > 0; i--, tkey++) {
1da177e4 LT	150	u32 *ptr;
	151	int offset = tkey->off;
	152
	153	if (tkey->offmask) {
	154	if (skb->len > tkey->at) {
	155	char *j = pptr + tkey->at;
10297b99 YH	156	offset += ((*j & tkey->offmask) >>
10297b99 YH	157	tkey->shift);
1da177e4 LT	158	} else {
	159	goto bad;
	160	}
	161	}
	162
	163	if (offset % 4) {
	164	printk("offset must be on 32 bit boundaries\n");
	165	goto bad;
	166	}
75202e76	167	if (offset > 0 && offset > skb->len) {
1da177e4 LT	168	printk("offset %d cant exceed pkt length %d\n",
	169	offset, skb->len);
	170	goto bad;
	171	}
	172
	173	ptr = (u32 *)(pptr+offset);
	174	/* just do it, baby */
	175	ptr = ((ptr & tkey->mask) ^ tkey->val);
	176	munged++;
	177	}
10297b99	178
1da177e4 LT	179	if (munged)
	180	skb->tc_verd = SET_TC_MUNGED(skb->tc_verd);
	181	goto done;
	182	} else {
e9ce1cd3	183	printk("pedit BUG: index %d\n", p->tcf_index);
1da177e4 LT	184	}
	185
	186	bad:
e9ce1cd3	187	p->tcf_qstats.overlimits++;
1da177e4	188	done:
e9ce1cd3 DM	189	p->tcf_bstats.bytes += skb->len;
	190	p->tcf_bstats.packets++;
	191	spin_unlock(&p->tcf_lock);
	192	return p->tcf_action;
1da177e4 LT	193	}
1da177e4 LT	194
e9ce1cd3 DM	195	static int tcf_pedit_dump(struct sk_buff skb, struct tc_action a,
e9ce1cd3 DM	196	int bind, int ref)
1da177e4	197	{
27a884dc	198	unsigned char *b = skb_tail_pointer(skb);
e9ce1cd3	199	struct tcf_pedit *p = a->priv;
1da177e4	200	struct tc_pedit *opt;
1da177e4	201	struct tcf_t t;
10297b99 YH	202	int s;
10297b99 YH	203
e9ce1cd3	204	s = sizeof(opt) + p->tcfp_nkeys sizeof(struct tc_pedit_key);
1da177e4 LT	205
1da177e4 LT	206	/* netlink spinlocks held above us - must use ATOMIC */
0da974f4	207	opt = kzalloc(s, GFP_ATOMIC);
e9ce1cd3	208	if (unlikely(!opt))
1da177e4	209	return -ENOBUFS;
1da177e4	210
e9ce1cd3 DM	211	memcpy(opt->keys, p->tcfp_keys,
	212	p->tcfp_nkeys * sizeof(struct tc_pedit_key));
	213	opt->index = p->tcf_index;
	214	opt->nkeys = p->tcfp_nkeys;
	215	opt->flags = p->tcfp_flags;
	216	opt->action = p->tcf_action;
	217	opt->refcnt = p->tcf_refcnt - ref;
	218	opt->bindcnt = p->tcf_bindcnt - bind;
1da177e4 LT	219
1da177e4 LT	220	RTA_PUT(skb, TCA_PEDIT_PARMS, s, opt);
e9ce1cd3 DM	221	t.install = jiffies_to_clock_t(jiffies - p->tcf_tm.install);
	222	t.lastuse = jiffies_to_clock_t(jiffies - p->tcf_tm.lastuse);
	223	t.expires = jiffies_to_clock_t(p->tcf_tm.expires);
1da177e4	224	RTA_PUT(skb, TCA_PEDIT_TM, sizeof(t), &t);
541673c8	225	kfree(opt);
1da177e4 LT	226	return skb->len;
	227
	228	rtattr_failure:
dc5fc579	229	nlmsg_trim(skb, b);
541673c8	230	kfree(opt);
1da177e4 LT	231	return -1;
	232	}
	233
e9ce1cd3	234	static struct tc_action_ops act_pedit_ops = {
1da177e4	235	.kind = "pedit",
e9ce1cd3	236	.hinfo = &pedit_hash_info,
1da177e4 LT	237	.type = TCA_ACT_PEDIT,
	238	.capab = TCA_CAP_NONE,
	239	.owner = THIS_MODULE,
	240	.act = tcf_pedit,
	241	.dump = tcf_pedit_dump,
	242	.cleanup = tcf_pedit_cleanup,
	243	.lookup = tcf_hash_search,
	244	.init = tcf_pedit_init,
	245	.walk = tcf_generic_walker
	246	};
	247
	248	MODULE_AUTHOR("Jamal Hadi Salim(2002-4)");
	249	MODULE_DESCRIPTION("Generic Packet Editor actions");
	250	MODULE_LICENSE("GPL");
	251
e9ce1cd3	252	static int __init pedit_init_module(void)
1da177e4 LT	253	{
	254	return tcf_register_action(&act_pedit_ops);
	255	}
	256
e9ce1cd3	257	static void __exit pedit_cleanup_module(void)
1da177e4 LT	258	{
	259	tcf_unregister_action(&act_pedit_ops);
	260	}
	261
	262	module_init(pedit_init_module);
	263	module_exit(pedit_cleanup_module);
	264