[deliverable/linux.git] / net / sched / act_ipt.c

/*
 * net/sched/ipt.c	iptables target interface
 *
 *TODO: Add other tables. For now we only support the ipv4 table targets
 *
 *		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.
 *
 * Copyright:	Jamal Hadi Salim (2002-4)
 */

#include <asm/uaccess.h>
#include <asm/system.h>
#include <asm/bitops.h>
#include <linux/config.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 <linux/kmod.h>
#include <net/sock.h>
#include <net/pkt_sched.h>
#include <linux/tc_act/tc_ipt.h>
#include <net/tc_act/tc_ipt.h>

#include <linux/netfilter_ipv4/ip_tables.h>

/* use generic hash table */
#define MY_TAB_SIZE     16
#define MY_TAB_MASK     15

static u32 idx_gen;
static struct tcf_ipt *tcf_ipt_ht[MY_TAB_SIZE];
/* ipt hash table lock */
static DEFINE_RWLOCK(ipt_lock);

/* ovewrride the defaults */
#define tcf_st		tcf_ipt
#define tcf_t_lock	ipt_lock
#define tcf_ht		tcf_ipt_ht

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

static int
ipt_init_target(struct ipt_entry_target *t, char *table, unsigned int hook)
{
	struct ipt_target *target;
	int ret = 0;

	target = xt_find_target(AF_INET, t->u.user.name, t->u.user.revision);
	if (!target)
		return -ENOENT;

	DPRINTK("ipt_init_target: found %s\n", target->name);
	t->u.kernel.target = target;

	if (t->u.kernel.target->checkentry
	    && !t->u.kernel.target->checkentry(table, NULL,
		    			       t->u.kernel.target, t->data,
					       t->u.target_size - sizeof(*t),
					       hook)) {
		DPRINTK("ipt_init_target: check failed for `%s'.\n",
			t->u.kernel.target->name);
		module_put(t->u.kernel.target->me);
		ret = -EINVAL;
	}

	return ret;
}

static void
ipt_destroy_target(struct ipt_entry_target *t)
{
	if (t->u.kernel.target->destroy)
		t->u.kernel.target->destroy(t->u.kernel.target, t->data,
		                            t->u.target_size - sizeof(*t));
        module_put(t->u.kernel.target->me);
}

static int
tcf_ipt_release(struct tcf_ipt *p, int bind)
{
	int ret = 0;
	if (p) {
		if (bind)
			p->bindcnt--;
		p->refcnt--;
		if (p->bindcnt <= 0 && p->refcnt <= 0) {
			ipt_destroy_target(p->t);
			kfree(p->tname);
			kfree(p->t);
			tcf_hash_destroy(p);
			ret = ACT_P_DELETED;
		}
	}
	return ret;
}

static int
tcf_ipt_init(struct rtattr *rta, struct rtattr *est, struct tc_action *a,
             int ovr, int bind)
{
	struct rtattr *tb[TCA_IPT_MAX];
	struct tcf_ipt *p;
	struct ipt_entry_target *td, *t;
	char *tname;
	int ret = 0, err;
	u32 hook = 0;
	u32 index = 0;

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

	if (tb[TCA_IPT_HOOK-1] == NULL ||
	    RTA_PAYLOAD(tb[TCA_IPT_HOOK-1]) < sizeof(u32))
		return -EINVAL;
	if (tb[TCA_IPT_TARG-1] == NULL ||
	    RTA_PAYLOAD(tb[TCA_IPT_TARG-1]) < sizeof(*t))
		return -EINVAL;
	td = (struct ipt_entry_target *)RTA_DATA(tb[TCA_IPT_TARG-1]);
	if (RTA_PAYLOAD(tb[TCA_IPT_TARG-1]) < td->u.target_size)
		return -EINVAL;

	if (tb[TCA_IPT_INDEX-1] != NULL &&
	    RTA_PAYLOAD(tb[TCA_IPT_INDEX-1]) >= sizeof(u32))
		index = *(u32 *)RTA_DATA(tb[TCA_IPT_INDEX-1]);

	p = tcf_hash_check(index, a, ovr, bind);
	if (p == NULL) {
		p = tcf_hash_create(index, est, a, sizeof(*p), ovr, bind);
		if (p == NULL)
			return -ENOMEM;
		ret = ACT_P_CREATED;
	} else {
		if (!ovr) {
			tcf_ipt_release(p, bind);
			return -EEXIST;
		}
	}

	hook = *(u32 *)RTA_DATA(tb[TCA_IPT_HOOK-1]);

	err = -ENOMEM;
	tname = kmalloc(IFNAMSIZ, GFP_KERNEL);
	if (tname == NULL)
		goto err1;
	if (tb[TCA_IPT_TABLE - 1] == NULL ||
	    rtattr_strlcpy(tname, tb[TCA_IPT_TABLE-1], IFNAMSIZ) >= IFNAMSIZ)
		strcpy(tname, "mangle");

	t = kmalloc(td->u.target_size, GFP_KERNEL);
	if (t == NULL)
		goto err2;
	memcpy(t, td, td->u.target_size);

	if ((err = ipt_init_target(t, tname, hook)) < 0)
		goto err3;

	spin_lock_bh(&p->lock);
	if (ret != ACT_P_CREATED) {
		ipt_destroy_target(p->t);
		kfree(p->tname);
		kfree(p->t);
	}
	p->tname = tname;
	p->t     = t;
	p->hook  = hook;
	spin_unlock_bh(&p->lock);
	if (ret == ACT_P_CREATED)
		tcf_hash_insert(p);
	return ret;

err3:
	kfree(t);
err2:
	kfree(tname);
err1:
	kfree(p);
	return err;
}

static int
tcf_ipt_cleanup(struct tc_action *a, int bind)
{
	struct tcf_ipt *p = PRIV(a, ipt);
	return tcf_ipt_release(p, bind);
}

static int
tcf_ipt(struct sk_buff *skb, struct tc_action *a, struct tcf_result *res)
{
	int ret = 0, result = 0;
	struct tcf_ipt *p = PRIV(a, ipt);

	if (skb_cloned(skb)) {
		if (pskb_expand_head(skb, 0, 0, GFP_ATOMIC))
			return TC_ACT_UNSPEC;
	}

	spin_lock(&p->lock);

	p->tm.lastuse = jiffies;
	p->bstats.bytes += skb->len;
	p->bstats.packets++;

	/* yes, we have to worry about both in and out dev
	 worry later - danger - this API seems to have changed
	 from earlier kernels */

	/* iptables targets take a double skb pointer in case the skb
	 * needs to be replaced. We don't own the skb, so this must not
	 * happen. The pskb_expand_head above should make sure of this */
	ret = p->t->u.kernel.target->target(&skb, skb->dev, NULL, p->hook,
					    p->t->u.kernel.target, p->t->data,
					    NULL);
	switch (ret) {
	case NF_ACCEPT:
		result = TC_ACT_OK;
		break;
	case NF_DROP:
		result = TC_ACT_SHOT;
		p->qstats.drops++;
		break;
	case IPT_CONTINUE:
		result = TC_ACT_PIPE;
		break;
	default:
		if (net_ratelimit())
			printk("Bogus netfilter code %d assume ACCEPT\n", ret);
		result = TC_POLICE_OK;
		break;
	}
	spin_unlock(&p->lock);
	return result;

}

static int
tcf_ipt_dump(struct sk_buff *skb, struct tc_action *a, int bind, int ref)
{
	struct ipt_entry_target *t;
	struct tcf_t tm;
	struct tc_cnt c;
	unsigned char *b = skb->tail;
	struct tcf_ipt *p = PRIV(a, ipt);

	/* for simple targets kernel size == user size
	** user name = target name
	** for foolproof you need to not assume this
	*/

	t = kmalloc(p->t->u.user.target_size, GFP_ATOMIC);
	if (t == NULL)
		goto rtattr_failure;

	c.bindcnt = p->bindcnt - bind;
	c.refcnt = p->refcnt - ref;
	memcpy(t, p->t, p->t->u.user.target_size);
	strcpy(t->u.user.name, p->t->u.kernel.target->name);

	DPRINTK("\ttcf_ipt_dump tablename %s length %d\n", p->tname,
		strlen(p->tname));
	DPRINTK("\tdump target name %s size %d size user %d "
	        "data[0] %x data[1] %x\n", p->t->u.kernel.target->name,
	        p->t->u.target_size, p->t->u.user.target_size,
	        p->t->data[0], p->t->data[1]);
	RTA_PUT(skb, TCA_IPT_TARG, p->t->u.user.target_size, t);
	RTA_PUT(skb, TCA_IPT_INDEX, 4, &p->index);
	RTA_PUT(skb, TCA_IPT_HOOK, 4, &p->hook);
	RTA_PUT(skb, TCA_IPT_CNT, sizeof(struct tc_cnt), &c);
	RTA_PUT(skb, TCA_IPT_TABLE, IFNAMSIZ, p->tname);
	tm.install = jiffies_to_clock_t(jiffies - p->tm.install);
	tm.lastuse = jiffies_to_clock_t(jiffies - p->tm.lastuse);
	tm.expires = jiffies_to_clock_t(p->tm.expires);
	RTA_PUT(skb, TCA_IPT_TM, sizeof (tm), &tm);
	kfree(t);
	return skb->len;

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

static struct tc_action_ops act_ipt_ops = {
	.kind		=	"ipt",
	.type		=	TCA_ACT_IPT,
	.capab		=	TCA_CAP_NONE,
	.owner		=	THIS_MODULE,
	.act		=	tcf_ipt,
	.dump		=	tcf_ipt_dump,
	.cleanup	=	tcf_ipt_cleanup,
	.lookup		=	tcf_hash_search,
	.init		=	tcf_ipt_init,
	.walk		=	tcf_generic_walker
};

MODULE_AUTHOR("Jamal Hadi Salim(2002-4)");
MODULE_DESCRIPTION("Iptables target actions");
MODULE_LICENSE("GPL");

static int __init
ipt_init_module(void)
{
	return tcf_register_action(&act_ipt_ops);
}

static void __exit
ipt_cleanup_module(void)
{
	tcf_unregister_action(&act_ipt_ops);
}

module_init(ipt_init_module);
module_exit(ipt_cleanup_module);
Commit	Line	Data
1da177e4 LT	1	/*
	2	* net/sched/ipt.c iptables target interface
	3	*
	4	*TODO: Add other tables. For now we only support the ipv4 table targets
	5	*
	6	* This program is free software; you can redistribute it and/or
	7	* modify it under the terms of the GNU General Public License
	8	* as published by the Free Software Foundation; either version
	9	* 2 of the License, or (at your option) any later version.
	10	*
	11	* Copyright: Jamal Hadi Salim (2002-4)
	12	*/
	13
	14	#include <asm/uaccess.h>
	15	#include <asm/system.h>
	16	#include <asm/bitops.h>
	17	#include <linux/config.h>
	18	#include <linux/types.h>
	19	#include <linux/kernel.h>
	20	#include <linux/sched.h>
	21	#include <linux/string.h>
	22	#include <linux/mm.h>
	23	#include <linux/socket.h>
	24	#include <linux/sockios.h>
	25	#include <linux/in.h>
	26	#include <linux/errno.h>
	27	#include <linux/interrupt.h>
	28	#include <linux/netdevice.h>
	29	#include <linux/skbuff.h>
	30	#include <linux/rtnetlink.h>
	31	#include <linux/module.h>
	32	#include <linux/init.h>
	33	#include <linux/proc_fs.h>
	34	#include <linux/kmod.h>
	35	#include <net/sock.h>
	36	#include <net/pkt_sched.h>
	37	#include <linux/tc_act/tc_ipt.h>
	38	#include <net/tc_act/tc_ipt.h>
	39
	40	#include <linux/netfilter_ipv4/ip_tables.h>
	41
	42	/* use generic hash table */
	43	#define MY_TAB_SIZE 16
	44	#define MY_TAB_MASK 15
	45
	46	static u32 idx_gen;
	47	static struct tcf_ipt *tcf_ipt_ht[MY_TAB_SIZE];
	48	/* ipt hash table lock */
	49	static DEFINE_RWLOCK(ipt_lock);
	50
	51	/* ovewrride the defaults */
	52	#define tcf_st tcf_ipt
	53	#define tcf_t_lock ipt_lock
	54	#define tcf_ht tcf_ipt_ht
	55
	56	#define CONFIG_NET_ACT_INIT
	57	#include <net/pkt_act.h>
	58
	59	static int
	60	ipt_init_target(struct ipt_entry_target t, char table, unsigned int hook)
	61	{
	62	struct ipt_target *target;
	63	int ret = 0;
	64
2e4e6a17	65	target = xt_find_target(AF_INET, t->u.user.name, t->u.user.revision);
1da177e4 LT	66	if (!target)
	67	return -ENOENT;
	68
	69	DPRINTK("ipt_init_target: found %s\n", target->name);
	70	t->u.kernel.target = target;
	71
	72	if (t->u.kernel.target->checkentry
1c524830 PM	73	&& !t->u.kernel.target->checkentry(table, NULL,
1c524830 PM	74	t->u.kernel.target, t->data,
1da177e4 LT	75	t->u.target_size - sizeof(*t),
	76	hook)) {
	77	DPRINTK("ipt_init_target: check failed for `%s'.\n",
	78	t->u.kernel.target->name);
	79	module_put(t->u.kernel.target->me);
	80	ret = -EINVAL;
	81	}
	82
	83	return ret;
	84	}
	85
	86	static void
	87	ipt_destroy_target(struct ipt_entry_target *t)
	88	{
	89	if (t->u.kernel.target->destroy)
1c524830	90	t->u.kernel.target->destroy(t->u.kernel.target, t->data,
1da177e4 LT	91	t->u.target_size - sizeof(*t));
	92	module_put(t->u.kernel.target->me);
	93	}
	94
	95	static int
	96	tcf_ipt_release(struct tcf_ipt *p, int bind)
	97	{
	98	int ret = 0;
	99	if (p) {
	100	if (bind)
	101	p->bindcnt--;
	102	p->refcnt--;
	103	if (p->bindcnt <= 0 && p->refcnt <= 0) {
	104	ipt_destroy_target(p->t);
	105	kfree(p->tname);
	106	kfree(p->t);
	107	tcf_hash_destroy(p);
	108	ret = ACT_P_DELETED;
	109	}
	110	}
	111	return ret;
	112	}
	113
	114	static int
	115	tcf_ipt_init(struct rtattr rta, struct rtattr est, struct tc_action *a,
	116	int ovr, int bind)
	117	{
	118	struct rtattr *tb[TCA_IPT_MAX];
	119	struct tcf_ipt *p;
	120	struct ipt_entry_target td, t;
	121	char *tname;
	122	int ret = 0, err;
	123	u32 hook = 0;
	124	u32 index = 0;
	125
	126	if (rta == NULL \|\| rtattr_parse_nested(tb, TCA_IPT_MAX, rta) < 0)
	127	return -EINVAL;
	128
	129	if (tb[TCA_IPT_HOOK-1] == NULL \|\|
	130	RTA_PAYLOAD(tb[TCA_IPT_HOOK-1]) < sizeof(u32))
	131	return -EINVAL;
	132	if (tb[TCA_IPT_TARG-1] == NULL \|\|
	133	RTA_PAYLOAD(tb[TCA_IPT_TARG-1]) < sizeof(*t))
	134	return -EINVAL;
	135	td = (struct ipt_entry_target *)RTA_DATA(tb[TCA_IPT_TARG-1]);
	136	if (RTA_PAYLOAD(tb[TCA_IPT_TARG-1]) < td->u.target_size)
	137	return -EINVAL;
	138
	139	if (tb[TCA_IPT_INDEX-1] != NULL &&
	140	RTA_PAYLOAD(tb[TCA_IPT_INDEX-1]) >= sizeof(u32))
	141	index = (u32 )RTA_DATA(tb[TCA_IPT_INDEX-1]);
	142
	143	p = tcf_hash_check(index, a, ovr, bind);
	144	if (p == NULL) {
	145	p = tcf_hash_create(index, est, a, sizeof(*p), ovr, bind);
	146	if (p == NULL)
	147	return -ENOMEM;
	148	ret = ACT_P_CREATED;
	149	} else {
	150	if (!ovr) {
	151	tcf_ipt_release(p, bind);
	152	return -EEXIST;
	153	}
	154	}
155
156	hook = (u32 )RTA_DATA(tb[TCA_IPT_HOOK-1]);
157
158	err = -ENOMEM;
159	tname = kmalloc(IFNAMSIZ, GFP_KERNEL);
160	if (tname == NULL)
161	goto err1;
162	if (tb[TCA_IPT_TABLE - 1] == NULL \|\|
163	rtattr_strlcpy(tname, tb[TCA_IPT_TABLE-1], IFNAMSIZ) >= IFNAMSIZ)
164	strcpy(tname, "mangle");
165
166	t = kmalloc(td->u.target_size, GFP_KERNEL);
167	if (t == NULL)
168	goto err2;
169	memcpy(t, td, td->u.target_size);
170
171	if ((err = ipt_init_target(t, tname, hook)) < 0)
172	goto err3;
173
174	spin_lock_bh(&p->lock);
175	if (ret != ACT_P_CREATED) {
176	ipt_destroy_target(p->t);
177	kfree(p->tname);
178	kfree(p->t);
179	}
180	p->tname = tname;
181	p->t = t;
182	p->hook = hook;
183	spin_unlock_bh(&p->lock);
184	if (ret == ACT_P_CREATED)
185	tcf_hash_insert(p);
186	return ret;
187
188	err3:
189	kfree(t);
190	err2:
191	kfree(tname);
192	err1:
193	kfree(p);
194	return err;
195	}
196
197	static int
198	tcf_ipt_cleanup(struct tc_action *a, int bind)
199	{
200	struct tcf_ipt *p = PRIV(a, ipt);
201	return tcf_ipt_release(p, bind);
202	}
203
204	static int
f43c5a0d	205	tcf_ipt(struct sk_buff skb, struct tc_action a, struct tcf_result *res)
1da177e4 LT	206	{
	207	int ret = 0, result = 0;
	208	struct tcf_ipt *p = PRIV(a, ipt);
1da177e4 LT	209
	210	if (skb_cloned(skb)) {
	211	if (pskb_expand_head(skb, 0, 0, GFP_ATOMIC))
	212	return TC_ACT_UNSPEC;
	213	}
	214
	215	spin_lock(&p->lock);
	216
	217	p->tm.lastuse = jiffies;
	218	p->bstats.bytes += skb->len;
	219	p->bstats.packets++;
	220
	221	/* yes, we have to worry about both in and out dev
	222	worry later - danger - this API seems to have changed
	223	from earlier kernels */
	224
f43c5a0d PM	225	/* iptables targets take a double skb pointer in case the skb
	226	* needs to be replaced. We don't own the skb, so this must not
	227	* happen. The pskb_expand_head above should make sure of this */
1c524830 PM	228	ret = p->t->u.kernel.target->target(&skb, skb->dev, NULL, p->hook,
	229	p->t->u.kernel.target, p->t->data,
	230	NULL);
1da177e4 LT	231	switch (ret) {
	232	case NF_ACCEPT:
	233	result = TC_ACT_OK;
	234	break;
	235	case NF_DROP:
	236	result = TC_ACT_SHOT;
	237	p->qstats.drops++;
	238	break;
	239	case IPT_CONTINUE:
	240	result = TC_ACT_PIPE;
	241	break;
	242	default:
	243	if (net_ratelimit())
	244	printk("Bogus netfilter code %d assume ACCEPT\n", ret);
	245	result = TC_POLICE_OK;
	246	break;
	247	}
	248	spin_unlock(&p->lock);
	249	return result;
	250
	251	}
	252
	253	static int
	254	tcf_ipt_dump(struct sk_buff skb, struct tc_action a, int bind, int ref)
	255	{
	256	struct ipt_entry_target *t;
	257	struct tcf_t tm;
	258	struct tc_cnt c;
	259	unsigned char *b = skb->tail;
	260	struct tcf_ipt *p = PRIV(a, ipt);
	261
	262	/* for simple targets kernel size == user size
	263	** user name = target name
	264	** for foolproof you need to not assume this
	265	*/
	266
	267	t = kmalloc(p->t->u.user.target_size, GFP_ATOMIC);
	268	if (t == NULL)
	269	goto rtattr_failure;
	270
	271	c.bindcnt = p->bindcnt - bind;
	272	c.refcnt = p->refcnt - ref;
	273	memcpy(t, p->t, p->t->u.user.target_size);
	274	strcpy(t->u.user.name, p->t->u.kernel.target->name);
	275
	276	DPRINTK("\ttcf_ipt_dump tablename %s length %d\n", p->tname,
	277	strlen(p->tname));
	278	DPRINTK("\tdump target name %s size %d size user %d "
	279	"data[0] %x data[1] %x\n", p->t->u.kernel.target->name,
	280	p->t->u.target_size, p->t->u.user.target_size,
	281	p->t->data[0], p->t->data[1]);
	282	RTA_PUT(skb, TCA_IPT_TARG, p->t->u.user.target_size, t);
	283	RTA_PUT(skb, TCA_IPT_INDEX, 4, &p->index);
	284	RTA_PUT(skb, TCA_IPT_HOOK, 4, &p->hook);
	285	RTA_PUT(skb, TCA_IPT_CNT, sizeof(struct tc_cnt), &c);
	286	RTA_PUT(skb, TCA_IPT_TABLE, IFNAMSIZ, p->tname);
	287	tm.install = jiffies_to_clock_t(jiffies - p->tm.install);
	288	tm.lastuse = jiffies_to_clock_t(jiffies - p->tm.lastuse);
	289	tm.expires = jiffies_to_clock_t(p->tm.expires);
	290	RTA_PUT(skb, TCA_IPT_TM, sizeof (tm), &tm);
	291	kfree(t);
	292	return skb->len;
	293
	294	rtattr_failure:
295	skb_trim(skb, b - skb->data);
296	kfree(t);
297	return -1;
298	}
299
300	static struct tc_action_ops act_ipt_ops = {
301	.kind = "ipt",
302	.type = TCA_ACT_IPT,
303	.capab = TCA_CAP_NONE,
304	.owner = THIS_MODULE,
305	.act = tcf_ipt,
306	.dump = tcf_ipt_dump,
307	.cleanup = tcf_ipt_cleanup,
308	.lookup = tcf_hash_search,
309	.init = tcf_ipt_init,
310	.walk = tcf_generic_walker
311	};
312
313	MODULE_AUTHOR("Jamal Hadi Salim(2002-4)");
314	MODULE_DESCRIPTION("Iptables target actions");
315	MODULE_LICENSE("GPL");
316
317	static int __init
318	ipt_init_module(void)
319	{
320	return tcf_register_action(&act_ipt_ops);
321	}
322
323	static void __exit
324	ipt_cleanup_module(void)
325	{
326	tcf_unregister_action(&act_ipt_ops);
327	}
328
329	module_init(ipt_init_module);
330	module_exit(ipt_cleanup_module);