[linux.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/sched.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/sock.h>
#include <net/pkt_sched.h>
#include <linux/tc_act/tc_pedit.h>
#include <net/tc_act/tc_pedit.h>


#define PEDIT_DEB 1

/* use generic hash table */
#define MY_TAB_SIZE     16
#define MY_TAB_MASK     15
static u32 idx_gen;
static struct tcf_pedit *tcf_pedit_ht[MY_TAB_SIZE];
static DEFINE_RWLOCK(pedit_lock);

#define tcf_st		tcf_pedit
#define tc_st		tc_pedit
#define tcf_t_lock	pedit_lock
#define tcf_ht		tcf_pedit_ht

#define CONFIG_NET_ACT_INIT 1
#include <net/pkt_act.h>

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 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;

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

	spin_lock_bh(&p->lock);
	p->flags = parm->flags;
	p->action = parm->action;
	if (keys) {
		kfree(p->keys);
		p->keys = keys;
		p->nkeys = parm->nkeys;
	}
	memcpy(p->keys, parm->keys, ksize);
	spin_unlock_bh(&p->lock);
	if (ret == ACT_P_CREATED)
		tcf_hash_insert(p);
	return ret;
}

static int
tcf_pedit_cleanup(struct tc_action *a, int bind)
{
	struct tcf_pedit *p = PRIV(a, pedit);

	if (p != NULL) {
		struct tc_pedit_key *keys = p->keys;
		if (tcf_hash_release(p, bind)) {
			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 = PRIV(a, pedit);
	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->action;
		}
	}

	pptr = skb->nh.raw;

	spin_lock(&p->lock);

	p->tm.lastuse = jiffies;

	if (p->nkeys > 0) {
		struct tc_pedit_key *tkey = p->keys;

		for (i = p->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 (skb->len < 0 || (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->index);
	}

bad:
	p->qstats.overlimits++;
done:
	p->bstats.bytes += skb->len;
	p->bstats.packets++;
	spin_unlock(&p->lock);
	return p->action;
}

static int
tcf_pedit_dump(struct sk_buff *skb, struct tc_action *a,int bind, int ref)
{
	unsigned char *b = skb->tail;
	struct tc_pedit *opt;
	struct tcf_pedit *p = PRIV(a, pedit);
	struct tcf_t t;
	int s; 
		
	s = sizeof(*opt) + p->nkeys * sizeof(struct tc_pedit_key);

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

	memcpy(opt->keys, p->keys, p->nkeys * sizeof(struct tc_pedit_key));
	opt->index = p->index;
	opt->nkeys = p->nkeys;
	opt->flags = p->flags;
	opt->action = p->action;
	opt->refcnt = p->refcnt - ref;
	opt->bindcnt = p->bindcnt - bind;


#ifdef PEDIT_DEB
	{                
		/* Debug - get rid of later */
		int i;
		struct tc_pedit_key *key = opt->keys;

		for (i=0; i<opt->nkeys; i++, key++) {
			printk( "\n key #%d",i);
			printk( "  at %d: val %08x mask %08x",
			(unsigned int)key->off,
			(unsigned int)key->val,
			(unsigned int)key->mask);
		}
	}
#endif

	RTA_PUT(skb, TCA_PEDIT_PARMS, s, opt);
	t.install = jiffies_to_clock_t(jiffies - p->tm.install);
	t.lastuse = jiffies_to_clock_t(jiffies - p->tm.lastuse);
	t.expires = jiffies_to_clock_t(p->tm.expires);
	RTA_PUT(skb, TCA_PEDIT_TM, sizeof(t), &t);
	kfree(opt);
	return skb->len;

rtattr_failure:
	skb_trim(skb, b - skb->data);
	kfree(opt);
	return -1;
}

static
struct tc_action_ops act_pedit_ops = {
	.kind		=	"pedit",
	.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>
	16	#include <linux/kernel.h>
	17	#include <linux/sched.h>
	18	#include <linux/string.h>
	19	#include <linux/mm.h>
	20	#include <linux/socket.h>
	21	#include <linux/sockios.h>
	22	#include <linux/in.h>
	23	#include <linux/errno.h>
	24	#include <linux/interrupt.h>
	25	#include <linux/netdevice.h>
	26	#include <linux/skbuff.h>
	27	#include <linux/rtnetlink.h>
	28	#include <linux/module.h>
	29	#include <linux/init.h>
	30	#include <linux/proc_fs.h>
	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
	36
	37	#define PEDIT_DEB 1
	38
	39	/* use generic hash table */
	40	#define MY_TAB_SIZE 16
	41	#define MY_TAB_MASK 15
	42	static u32 idx_gen;
	43	static struct tcf_pedit *tcf_pedit_ht[MY_TAB_SIZE];
	44	static DEFINE_RWLOCK(pedit_lock);
	45
	46	#define tcf_st tcf_pedit
	47	#define tc_st tc_pedit
	48	#define tcf_t_lock pedit_lock
	49	#define tcf_ht tcf_pedit_ht
	50
	51	#define CONFIG_NET_ACT_INIT 1
	52	#include <net/pkt_act.h>
	53
	54	static int
	55	tcf_pedit_init(struct rtattr rta, struct rtattr est, struct tc_action *a,
	56	int ovr, int bind)
	57	{
	58	struct rtattr *tb[TCA_PEDIT_MAX];
	59	struct tc_pedit *parm;
	60	int ret = 0;
	61	struct tcf_pedit *p;
	62	struct tc_pedit_key *keys = NULL;
	63	int ksize;
	64
	65	if (rta == NULL \|\| rtattr_parse_nested(tb, TCA_PEDIT_MAX, rta) < 0)
	66	return -EINVAL;
	67
	68	if (tb[TCA_PEDIT_PARMS - 1] == NULL \|\|
	69	RTA_PAYLOAD(tb[TCA_PEDIT_PARMS-1]) < sizeof(*parm))
	70	return -EINVAL;
	71	parm = RTA_DATA(tb[TCA_PEDIT_PARMS-1]);
	72	ksize = parm->nkeys * sizeof(struct tc_pedit_key);
	73	if (RTA_PAYLOAD(tb[TCA_PEDIT_PARMS-1]) < sizeof(*parm) + ksize)
	74	return -EINVAL;
	75
	76	p = tcf_hash_check(parm->index, a, ovr, bind);
	77	if (p == NULL) {
	78	if (!parm->nkeys)
79	return -EINVAL;
80	p = tcf_hash_create(parm->index, est, a, sizeof(*p), ovr, bind);
81	if (p == NULL)
82	return -ENOMEM;
83	keys = kmalloc(ksize, GFP_KERNEL);
84	if (keys == NULL) {
85	kfree(p);
86	return -ENOMEM;
87	}
88	ret = ACT_P_CREATED;
89	} else {
90	if (!ovr) {
91	tcf_hash_release(p, bind);
92	return -EEXIST;
93	}
94	if (p->nkeys && p->nkeys != parm->nkeys) {
95	keys = kmalloc(ksize, GFP_KERNEL);
96	if (keys == NULL)
97	return -ENOMEM;
98	}
99	}
100
101	spin_lock_bh(&p->lock);
102	p->flags = parm->flags;
103	p->action = parm->action;
104	if (keys) {
105	kfree(p->keys);
106	p->keys = keys;
107	p->nkeys = parm->nkeys;
108	}
109	memcpy(p->keys, parm->keys, ksize);
110	spin_unlock_bh(&p->lock);
111	if (ret == ACT_P_CREATED)
112	tcf_hash_insert(p);
113	return ret;
114	}
115
116	static int
117	tcf_pedit_cleanup(struct tc_action *a, int bind)
118	{
119	struct tcf_pedit *p = PRIV(a, pedit);
120
121	if (p != NULL) {
122	struct tc_pedit_key *keys = p->keys;
123	if (tcf_hash_release(p, bind)) {
124	kfree(keys);
125	return 1;
126	}
127	}
128	return 0;
129	}
130
131	static int
f43c5a0d	132	tcf_pedit(struct sk_buff skb, struct tc_action a, struct tcf_result *res)
1da177e4 LT	133	{
1da177e4 LT	134	struct tcf_pedit *p = PRIV(a, pedit);
1da177e4 LT	135	int i, munged = 0;
	136	u8 *pptr;
	137
	138	if (!(skb->tc_verd & TC_OK2MUNGE)) {
	139	/* should we set skb->cloned? */
	140	if (pskb_expand_head(skb, 0, 0, GFP_ATOMIC)) {
	141	return p->action;
	142	}
	143	}
	144
	145	pptr = skb->nh.raw;
	146
	147	spin_lock(&p->lock);
	148
	149	p->tm.lastuse = jiffies;
	150
	151	if (p->nkeys > 0) {
	152	struct tc_pedit_key *tkey = p->keys;
	153
	154	for (i = p->nkeys; i > 0; i--, tkey++) {
	155	u32 *ptr;
	156	int offset = tkey->off;
	157
	158	if (tkey->offmask) {
	159	if (skb->len > tkey->at) {
	160	char *j = pptr + tkey->at;
	161	offset += ((*j & tkey->offmask) >>
	162	tkey->shift);
	163	} else {
	164	goto bad;
	165	}
	166	}
	167
	168	if (offset % 4) {
	169	printk("offset must be on 32 bit boundaries\n");
	170	goto bad;
	171	}
	172	if (skb->len < 0 \|\| (offset > 0 && offset > skb->len)) {
	173	printk("offset %d cant exceed pkt length %d\n",
	174	offset, skb->len);
	175	goto bad;
	176	}
	177
	178	ptr = (u32 *)(pptr+offset);
	179	/* just do it, baby */
	180	ptr = ((ptr & tkey->mask) ^ tkey->val);
	181	munged++;
	182	}
	183
	184	if (munged)
	185	skb->tc_verd = SET_TC_MUNGED(skb->tc_verd);
	186	goto done;
	187	} else {
	188	printk("pedit BUG: index %d\n",p->index);
	189	}
	190
	191	bad:
	192	p->qstats.overlimits++;
	193	done:
	194	p->bstats.bytes += skb->len;
	195	p->bstats.packets++;
	196	spin_unlock(&p->lock);
	197	return p->action;
	198	}
199
200	static int
201	tcf_pedit_dump(struct sk_buff skb, struct tc_action a,int bind, int ref)
202	{
203	unsigned char *b = skb->tail;
204	struct tc_pedit *opt;
205	struct tcf_pedit *p = PRIV(a, pedit);
206	struct tcf_t t;
207	int s;
208
209	s = sizeof(opt) + p->nkeys sizeof(struct tc_pedit_key);
210
211	/* netlink spinlocks held above us - must use ATOMIC */
0da974f4	212	opt = kzalloc(s, GFP_ATOMIC);
1da177e4 LT	213	if (opt == NULL)
1da177e4 LT	214	return -ENOBUFS;
1da177e4 LT	215
	216	memcpy(opt->keys, p->keys, p->nkeys * sizeof(struct tc_pedit_key));
	217	opt->index = p->index;
	218	opt->nkeys = p->nkeys;
	219	opt->flags = p->flags;
	220	opt->action = p->action;
	221	opt->refcnt = p->refcnt - ref;
	222	opt->bindcnt = p->bindcnt - bind;
	223
	224
	225	#ifdef PEDIT_DEB
	226	{
	227	/* Debug - get rid of later */
	228	int i;
	229	struct tc_pedit_key *key = opt->keys;
	230
	231	for (i=0; i<opt->nkeys; i++, key++) {
	232	printk( "\n key #%d",i);
	233	printk( " at %d: val %08x mask %08x",
	234	(unsigned int)key->off,
	235	(unsigned int)key->val,
	236	(unsigned int)key->mask);
	237	}
	238	}
	239	#endif
	240
	241	RTA_PUT(skb, TCA_PEDIT_PARMS, s, opt);
	242	t.install = jiffies_to_clock_t(jiffies - p->tm.install);
	243	t.lastuse = jiffies_to_clock_t(jiffies - p->tm.lastuse);
	244	t.expires = jiffies_to_clock_t(p->tm.expires);
	245	RTA_PUT(skb, TCA_PEDIT_TM, sizeof(t), &t);
541673c8	246	kfree(opt);
1da177e4 LT	247	return skb->len;
	248
	249	rtattr_failure:
	250	skb_trim(skb, b - skb->data);
541673c8	251	kfree(opt);
1da177e4 LT	252	return -1;
	253	}
	254
	255	static
	256	struct tc_action_ops act_pedit_ops = {
	257	.kind = "pedit",
	258	.type = TCA_ACT_PEDIT,
	259	.capab = TCA_CAP_NONE,
	260	.owner = THIS_MODULE,
	261	.act = tcf_pedit,
	262	.dump = tcf_pedit_dump,
	263	.cleanup = tcf_pedit_cleanup,
	264	.lookup = tcf_hash_search,
	265	.init = tcf_pedit_init,
	266	.walk = tcf_generic_walker
	267	};
	268
	269	MODULE_AUTHOR("Jamal Hadi Salim(2002-4)");
	270	MODULE_DESCRIPTION("Generic Packet Editor actions");
	271	MODULE_LICENSE("GPL");
	272
	273	static int __init
	274	pedit_init_module(void)
	275	{
	276	return tcf_register_action(&act_pedit_ops);
	277	}
	278
	279	static void __exit
	280	pedit_cleanup_module(void)
	281	{
	282	tcf_unregister_action(&act_pedit_ops);
	283	}
	284
	285	module_init(pedit_init_module);
	286	module_exit(pedit_cleanup_module);
	287