[linux.git] / net / sched / act_mirred.c

/*
 * net/sched/mirred.c	packet mirroring and redirect actions
 *
 *		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)
 *
 * TODO: Add ingress support (and socket redirect support)
 *
 */

#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_mirred.h>
#include <net/tc_act/tc_mirred.h>

#include <linux/etherdevice.h>
#include <linux/if_arp.h>

#define MIRRED_TAB_MASK     7
static struct tcf_common *tcf_mirred_ht[MIRRED_TAB_MASK + 1];
static u32 mirred_idx_gen;
static DEFINE_RWLOCK(mirred_lock);

static struct tcf_hashinfo mirred_hash_info = {
	.htab	=	tcf_mirred_ht,
	.hmask	=	MIRRED_TAB_MASK,
	.lock	=	&mirred_lock,
};

static inline int tcf_mirred_release(struct tcf_mirred *m, int bind)
{
	if (m) {
		if (bind)
			m->tcf_bindcnt--;
		m->tcf_refcnt--;
		if(!m->tcf_bindcnt && m->tcf_refcnt <= 0) {
			dev_put(m->tcfm_dev);
			tcf_hash_destroy(&m->common, &mirred_hash_info);
			return 1;
		}
	}
	return 0;
}

static int tcf_mirred_init(struct rtattr *rta, struct rtattr *est,
			   struct tc_action *a, int ovr, int bind)
{
	struct rtattr *tb[TCA_MIRRED_MAX];
	struct tc_mirred *parm;
	struct tcf_mirred *m;
	struct tcf_common *pc;
	struct net_device *dev = NULL;
	int ret = 0;
	int ok_push = 0;

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

	if (tb[TCA_MIRRED_PARMS-1] == NULL ||
	    RTA_PAYLOAD(tb[TCA_MIRRED_PARMS-1]) < sizeof(*parm))
		return -EINVAL;
	parm = RTA_DATA(tb[TCA_MIRRED_PARMS-1]);

	if (parm->ifindex) {
		dev = __dev_get_by_index(parm->ifindex);
		if (dev == NULL)
			return -ENODEV;
		switch (dev->type) {
			case ARPHRD_TUNNEL:
			case ARPHRD_TUNNEL6:
			case ARPHRD_SIT:
			case ARPHRD_IPGRE:
			case ARPHRD_VOID:
			case ARPHRD_NONE:
				ok_push = 0;
				break;
			default:
				ok_push = 1;
				break;
		}
	}

	pc = tcf_hash_check(parm->index, a, bind, &mirred_hash_info);
	if (!pc) {
		if (!parm->ifindex)
			return -EINVAL;
		pc = tcf_hash_create(parm->index, est, a, sizeof(*m), bind,
				     &mirred_idx_gen, &mirred_hash_info);
		if (unlikely(!pc))
			return -ENOMEM;
		ret = ACT_P_CREATED;
	} else {
		if (!ovr) {
			tcf_mirred_release(to_mirred(pc), bind);
			return -EEXIST;
		}
	}
	m = to_mirred(pc);

	spin_lock_bh(&m->tcf_lock);
	m->tcf_action = parm->action;
	m->tcfm_eaction = parm->eaction;
	if (parm->ifindex) {
		m->tcfm_ifindex = parm->ifindex;
		if (ret != ACT_P_CREATED)
			dev_put(m->tcfm_dev);
		m->tcfm_dev = dev;
		dev_hold(dev);
		m->tcfm_ok_push = ok_push;
	}
	spin_unlock_bh(&m->tcf_lock);
	if (ret == ACT_P_CREATED)
		tcf_hash_insert(pc, &mirred_hash_info);

	return ret;
}

static int tcf_mirred_cleanup(struct tc_action *a, int bind)
{
	struct tcf_mirred *m = a->priv;

	if (m)
		return tcf_mirred_release(m, bind);
	return 0;
}

static int tcf_mirred(struct sk_buff *skb, struct tc_action *a,
		      struct tcf_result *res)
{
	struct tcf_mirred *m = a->priv;
	struct net_device *dev;
	struct sk_buff *skb2 = NULL;
	u32 at = G_TC_AT(skb->tc_verd);

	spin_lock(&m->tcf_lock);

	dev = m->tcfm_dev;
	m->tcf_tm.lastuse = jiffies;

	if (!(dev->flags&IFF_UP) ) {
		if (net_ratelimit())
			printk("mirred to Houston: device %s is gone!\n",
			       dev->name);
bad_mirred:
		if (skb2 != NULL)
			kfree_skb(skb2);
		m->tcf_qstats.overlimits++;
		m->tcf_bstats.bytes += skb->len;
		m->tcf_bstats.packets++;
		spin_unlock(&m->tcf_lock);
		/* should we be asking for packet to be dropped?
		 * may make sense for redirect case only
		*/
		return TC_ACT_SHOT;
	}

	skb2 = skb_clone(skb, GFP_ATOMIC);
	if (skb2 == NULL)
		goto bad_mirred;
	if (m->tcfm_eaction != TCA_EGRESS_MIRROR &&
	    m->tcfm_eaction != TCA_EGRESS_REDIR) {
		if (net_ratelimit())
			printk("tcf_mirred unknown action %d\n",
			       m->tcfm_eaction);
		goto bad_mirred;
	}

	m->tcf_bstats.bytes += skb2->len;
	m->tcf_bstats.packets++;
	if (!(at & AT_EGRESS))
		if (m->tcfm_ok_push)
			skb_push(skb2, skb2->dev->hard_header_len);

	/* mirror is always swallowed */
	if (m->tcfm_eaction != TCA_EGRESS_MIRROR)
		skb2->tc_verd = SET_TC_FROM(skb2->tc_verd, at);

	skb2->dev = dev;
	skb2->input_dev = skb->dev;
	dev_queue_xmit(skb2);
	spin_unlock(&m->tcf_lock);
	return m->tcf_action;
}

static int tcf_mirred_dump(struct sk_buff *skb, struct tc_action *a, int bind, int ref)
{
	unsigned char *b = skb->tail;
	struct tcf_mirred *m = a->priv;
	struct tc_mirred opt;
	struct tcf_t t;

	opt.index = m->tcf_index;
	opt.action = m->tcf_action;
	opt.refcnt = m->tcf_refcnt - ref;
	opt.bindcnt = m->tcf_bindcnt - bind;
	opt.eaction = m->tcfm_eaction;
	opt.ifindex = m->tcfm_ifindex;
	RTA_PUT(skb, TCA_MIRRED_PARMS, sizeof(opt), &opt);
	t.install = jiffies_to_clock_t(jiffies - m->tcf_tm.install);
	t.lastuse = jiffies_to_clock_t(jiffies - m->tcf_tm.lastuse);
	t.expires = jiffies_to_clock_t(m->tcf_tm.expires);
	RTA_PUT(skb, TCA_MIRRED_TM, sizeof(t), &t);
	return skb->len;

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

static struct tc_action_ops act_mirred_ops = {
	.kind		=	"mirred",
	.hinfo		=	&mirred_hash_info,
	.type		=	TCA_ACT_MIRRED,
	.capab		=	TCA_CAP_NONE,
	.owner		=	THIS_MODULE,
	.act		=	tcf_mirred,
	.dump		=	tcf_mirred_dump,
	.cleanup	=	tcf_mirred_cleanup,
	.lookup		=	tcf_hash_search,
	.init		=	tcf_mirred_init,
	.walk		=	tcf_generic_walker
};

MODULE_AUTHOR("Jamal Hadi Salim(2002)");
MODULE_DESCRIPTION("Device Mirror/redirect actions");
MODULE_LICENSE("GPL");

static int __init mirred_init_module(void)
{
	printk("Mirror/redirect action on\n");
	return tcf_register_action(&act_mirred_ops);
}

static void __exit mirred_cleanup_module(void)
{
	tcf_unregister_action(&act_mirred_ops);
}

module_init(mirred_init_module);
module_exit(mirred_cleanup_module);
Commit	Line	Data
1da177e4 LT	1	/*
	2	* net/sched/mirred.c packet mirroring and redirect actions
	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	* TODO: Add ingress support (and socket redirect support)
	12	*
	13	*/
	14
	15	#include <asm/uaccess.h>
	16	#include <asm/system.h>
	17	#include <asm/bitops.h>
1da177e4 LT	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 <net/sock.h>
	35	#include <net/pkt_sched.h>
	36	#include <linux/tc_act/tc_mirred.h>
	37	#include <net/tc_act/tc_mirred.h>
	38
	39	#include <linux/etherdevice.h>
	40	#include <linux/if_arp.h>
	41
e9ce1cd3 DM	42	#define MIRRED_TAB_MASK 7
	43	static struct tcf_common *tcf_mirred_ht[MIRRED_TAB_MASK + 1];
	44	static u32 mirred_idx_gen;
1da177e4 LT	45	static DEFINE_RWLOCK(mirred_lock);
1da177e4 LT	46
e9ce1cd3 DM	47	static struct tcf_hashinfo mirred_hash_info = {
	48	.htab = tcf_mirred_ht,
	49	.hmask = MIRRED_TAB_MASK,
	50	.lock = &mirred_lock,
	51	};
1da177e4	52
e9ce1cd3	53	static inline int tcf_mirred_release(struct tcf_mirred *m, int bind)
1da177e4	54	{
e9ce1cd3	55	if (m) {
1da177e4	56	if (bind)
e9ce1cd3 DM	57	m->tcf_bindcnt--;
	58	m->tcf_refcnt--;
	59	if(!m->tcf_bindcnt && m->tcf_refcnt <= 0) {
	60	dev_put(m->tcfm_dev);
	61	tcf_hash_destroy(&m->common, &mirred_hash_info);
1da177e4 LT	62	return 1;
	63	}
	64	}
	65	return 0;
	66	}
	67
e9ce1cd3 DM	68	static int tcf_mirred_init(struct rtattr rta, struct rtattr est,
e9ce1cd3 DM	69	struct tc_action *a, int ovr, int bind)
1da177e4 LT	70	{
	71	struct rtattr *tb[TCA_MIRRED_MAX];
	72	struct tc_mirred *parm;
e9ce1cd3 DM	73	struct tcf_mirred *m;
e9ce1cd3 DM	74	struct tcf_common *pc;
1da177e4 LT	75	struct net_device *dev = NULL;
	76	int ret = 0;
	77	int ok_push = 0;
	78
	79	if (rta == NULL \|\| rtattr_parse_nested(tb, TCA_MIRRED_MAX, rta) < 0)
	80	return -EINVAL;
	81
	82	if (tb[TCA_MIRRED_PARMS-1] == NULL \|\|
	83	RTA_PAYLOAD(tb[TCA_MIRRED_PARMS-1]) < sizeof(*parm))
	84	return -EINVAL;
	85	parm = RTA_DATA(tb[TCA_MIRRED_PARMS-1]);
	86
	87	if (parm->ifindex) {
	88	dev = __dev_get_by_index(parm->ifindex);
	89	if (dev == NULL)
	90	return -ENODEV;
	91	switch (dev->type) {
	92	case ARPHRD_TUNNEL:
	93	case ARPHRD_TUNNEL6:
	94	case ARPHRD_SIT:
	95	case ARPHRD_IPGRE:
	96	case ARPHRD_VOID:
	97	case ARPHRD_NONE:
	98	ok_push = 0;
	99	break;
	100	default:
	101	ok_push = 1;
	102	break;
	103	}
	104	}
	105
e9ce1cd3 DM	106	pc = tcf_hash_check(parm->index, a, bind, &mirred_hash_info);
e9ce1cd3 DM	107	if (!pc) {
1da177e4 LT	108	if (!parm->ifindex)
1da177e4 LT	109	return -EINVAL;
e9ce1cd3 DM	110	pc = tcf_hash_create(parm->index, est, a, sizeof(*m), bind,
	111	&mirred_idx_gen, &mirred_hash_info);
	112	if (unlikely(!pc))
1da177e4 LT	113	return -ENOMEM;
	114	ret = ACT_P_CREATED;
	115	} else {
	116	if (!ovr) {
e9ce1cd3	117	tcf_mirred_release(to_mirred(pc), bind);
1da177e4 LT	118	return -EEXIST;
	119	}
	120	}
e9ce1cd3	121	m = to_mirred(pc);
1da177e4	122
e9ce1cd3 DM	123	spin_lock_bh(&m->tcf_lock);
	124	m->tcf_action = parm->action;
	125	m->tcfm_eaction = parm->eaction;
1da177e4	126	if (parm->ifindex) {
e9ce1cd3	127	m->tcfm_ifindex = parm->ifindex;
1da177e4	128	if (ret != ACT_P_CREATED)
e9ce1cd3 DM	129	dev_put(m->tcfm_dev);
e9ce1cd3 DM	130	m->tcfm_dev = dev;
1da177e4	131	dev_hold(dev);
e9ce1cd3	132	m->tcfm_ok_push = ok_push;
1da177e4	133	}
e9ce1cd3	134	spin_unlock_bh(&m->tcf_lock);
1da177e4	135	if (ret == ACT_P_CREATED)
e9ce1cd3	136	tcf_hash_insert(pc, &mirred_hash_info);
1da177e4	137
1da177e4 LT	138	return ret;
	139	}
	140
e9ce1cd3	141	static int tcf_mirred_cleanup(struct tc_action *a, int bind)
1da177e4	142	{
e9ce1cd3	143	struct tcf_mirred *m = a->priv;
1da177e4	144
e9ce1cd3 DM	145	if (m)
e9ce1cd3 DM	146	return tcf_mirred_release(m, bind);
1da177e4 LT	147	return 0;
	148	}
	149
e9ce1cd3 DM	150	static int tcf_mirred(struct sk_buff skb, struct tc_action a,
e9ce1cd3 DM	151	struct tcf_result *res)
1da177e4	152	{
e9ce1cd3	153	struct tcf_mirred *m = a->priv;
1da177e4 LT	154	struct net_device *dev;
1da177e4 LT	155	struct sk_buff *skb2 = NULL;
1da177e4 LT	156	u32 at = G_TC_AT(skb->tc_verd);
1da177e4 LT	157
e9ce1cd3	158	spin_lock(&m->tcf_lock);
1da177e4	159
e9ce1cd3 DM	160	dev = m->tcfm_dev;
e9ce1cd3 DM	161	m->tcf_tm.lastuse = jiffies;
1da177e4 LT	162
	163	if (!(dev->flags&IFF_UP) ) {
	164	if (net_ratelimit())
	165	printk("mirred to Houston: device %s is gone!\n",
	166	dev->name);
	167	bad_mirred:
	168	if (skb2 != NULL)
	169	kfree_skb(skb2);
e9ce1cd3 DM	170	m->tcf_qstats.overlimits++;
	171	m->tcf_bstats.bytes += skb->len;
	172	m->tcf_bstats.packets++;
	173	spin_unlock(&m->tcf_lock);
1da177e4 LT	174	/* should we be asking for packet to be dropped?
	175	* may make sense for redirect case only
	176	*/
	177	return TC_ACT_SHOT;
	178	}
	179
	180	skb2 = skb_clone(skb, GFP_ATOMIC);
	181	if (skb2 == NULL)
	182	goto bad_mirred;
e9ce1cd3 DM	183	if (m->tcfm_eaction != TCA_EGRESS_MIRROR &&
e9ce1cd3 DM	184	m->tcfm_eaction != TCA_EGRESS_REDIR) {
1da177e4	185	if (net_ratelimit())
e9ce1cd3 DM	186	printk("tcf_mirred unknown action %d\n",
e9ce1cd3 DM	187	m->tcfm_eaction);
1da177e4 LT	188	goto bad_mirred;
	189	}
	190
e9ce1cd3 DM	191	m->tcf_bstats.bytes += skb2->len;
e9ce1cd3 DM	192	m->tcf_bstats.packets++;
1da177e4	193	if (!(at & AT_EGRESS))
e9ce1cd3	194	if (m->tcfm_ok_push)
1da177e4 LT	195	skb_push(skb2, skb2->dev->hard_header_len);
	196
	197	/* mirror is always swallowed */
e9ce1cd3	198	if (m->tcfm_eaction != TCA_EGRESS_MIRROR)
1da177e4 LT	199	skb2->tc_verd = SET_TC_FROM(skb2->tc_verd, at);
	200
	201	skb2->dev = dev;
	202	skb2->input_dev = skb->dev;
	203	dev_queue_xmit(skb2);
e9ce1cd3 DM	204	spin_unlock(&m->tcf_lock);
e9ce1cd3 DM	205	return m->tcf_action;
1da177e4 LT	206	}
1da177e4 LT	207
e9ce1cd3	208	static int tcf_mirred_dump(struct sk_buff skb, struct tc_action a, int bind, int ref)
1da177e4 LT	209	{
1da177e4 LT	210	unsigned char *b = skb->tail;
e9ce1cd3	211	struct tcf_mirred *m = a->priv;
1da177e4	212	struct tc_mirred opt;
1da177e4 LT	213	struct tcf_t t;
1da177e4 LT	214
e9ce1cd3 DM	215	opt.index = m->tcf_index;
	216	opt.action = m->tcf_action;
	217	opt.refcnt = m->tcf_refcnt - ref;
	218	opt.bindcnt = m->tcf_bindcnt - bind;
	219	opt.eaction = m->tcfm_eaction;
	220	opt.ifindex = m->tcfm_ifindex;
1da177e4	221	RTA_PUT(skb, TCA_MIRRED_PARMS, sizeof(opt), &opt);
e9ce1cd3 DM	222	t.install = jiffies_to_clock_t(jiffies - m->tcf_tm.install);
	223	t.lastuse = jiffies_to_clock_t(jiffies - m->tcf_tm.lastuse);
	224	t.expires = jiffies_to_clock_t(m->tcf_tm.expires);
1da177e4 LT	225	RTA_PUT(skb, TCA_MIRRED_TM, sizeof(t), &t);
	226	return skb->len;
	227
e9ce1cd3	228	rtattr_failure:
1da177e4 LT	229	skb_trim(skb, b - skb->data);
	230	return -1;
	231	}
	232
	233	static struct tc_action_ops act_mirred_ops = {
	234	.kind = "mirred",
e9ce1cd3	235	.hinfo = &mirred_hash_info,
1da177e4 LT	236	.type = TCA_ACT_MIRRED,
	237	.capab = TCA_CAP_NONE,
	238	.owner = THIS_MODULE,
	239	.act = tcf_mirred,
	240	.dump = tcf_mirred_dump,
	241	.cleanup = tcf_mirred_cleanup,
	242	.lookup = tcf_hash_search,
	243	.init = tcf_mirred_init,
	244	.walk = tcf_generic_walker
	245	};
	246
	247	MODULE_AUTHOR("Jamal Hadi Salim(2002)");
	248	MODULE_DESCRIPTION("Device Mirror/redirect actions");
	249	MODULE_LICENSE("GPL");
	250
e9ce1cd3	251	static int __init mirred_init_module(void)
1da177e4 LT	252	{
	253	printk("Mirror/redirect action on\n");
	254	return tcf_register_action(&act_mirred_ops);
	255	}
	256
e9ce1cd3	257	static void __exit mirred_cleanup_module(void)
1da177e4 LT	258	{
	259	tcf_unregister_action(&act_mirred_ops);
	260	}
	261
	262	module_init(mirred_init_module);
	263	module_exit(mirred_cleanup_module);