[deliverable/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 <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 <net/netlink.h>
#include <net/pkt_sched.h>
#include <linux/tc_act/tc_mirred.h>
#include <net/tc_act/tc_mirred.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->iif = skb->dev->ifindex;
	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_pointer(skb);
	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:
	nlmsg_trim(skb, b);
	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
1da177e4 LT	15	#include <linux/types.h>
1da177e4 LT	16	#include <linux/kernel.h>
1da177e4	17	#include <linux/string.h>
1da177e4	18	#include <linux/errno.h>
1da177e4 LT	19	#include <linux/skbuff.h>
	20	#include <linux/rtnetlink.h>
	21	#include <linux/module.h>
	22	#include <linux/init.h>
dc5fc579	23	#include <net/netlink.h>
1da177e4 LT	24	#include <net/pkt_sched.h>
	25	#include <linux/tc_act/tc_mirred.h>
	26	#include <net/tc_act/tc_mirred.h>
	27
1da177e4 LT	28	#include <linux/if_arp.h>
1da177e4 LT	29
e9ce1cd3 DM	30	#define MIRRED_TAB_MASK 7
	31	static struct tcf_common *tcf_mirred_ht[MIRRED_TAB_MASK + 1];
	32	static u32 mirred_idx_gen;
1da177e4 LT	33	static DEFINE_RWLOCK(mirred_lock);
1da177e4 LT	34
e9ce1cd3 DM	35	static struct tcf_hashinfo mirred_hash_info = {
	36	.htab = tcf_mirred_ht,
	37	.hmask = MIRRED_TAB_MASK,
	38	.lock = &mirred_lock,
	39	};
1da177e4	40
e9ce1cd3	41	static inline int tcf_mirred_release(struct tcf_mirred *m, int bind)
1da177e4	42	{
e9ce1cd3	43	if (m) {
1da177e4	44	if (bind)
e9ce1cd3 DM	45	m->tcf_bindcnt--;
	46	m->tcf_refcnt--;
	47	if(!m->tcf_bindcnt && m->tcf_refcnt <= 0) {
	48	dev_put(m->tcfm_dev);
	49	tcf_hash_destroy(&m->common, &mirred_hash_info);
1da177e4 LT	50	return 1;
	51	}
	52	}
	53	return 0;
	54	}
	55
e9ce1cd3 DM	56	static int tcf_mirred_init(struct rtattr rta, struct rtattr est,
e9ce1cd3 DM	57	struct tc_action *a, int ovr, int bind)
1da177e4 LT	58	{
	59	struct rtattr *tb[TCA_MIRRED_MAX];
	60	struct tc_mirred *parm;
e9ce1cd3 DM	61	struct tcf_mirred *m;
e9ce1cd3 DM	62	struct tcf_common *pc;
1da177e4 LT	63	struct net_device *dev = NULL;
	64	int ret = 0;
	65	int ok_push = 0;
	66
	67	if (rta == NULL \|\| rtattr_parse_nested(tb, TCA_MIRRED_MAX, rta) < 0)
	68	return -EINVAL;
	69
	70	if (tb[TCA_MIRRED_PARMS-1] == NULL \|\|
	71	RTA_PAYLOAD(tb[TCA_MIRRED_PARMS-1]) < sizeof(*parm))
	72	return -EINVAL;
	73	parm = RTA_DATA(tb[TCA_MIRRED_PARMS-1]);
	74
	75	if (parm->ifindex) {
	76	dev = __dev_get_by_index(parm->ifindex);
	77	if (dev == NULL)
	78	return -ENODEV;
	79	switch (dev->type) {
	80	case ARPHRD_TUNNEL:
	81	case ARPHRD_TUNNEL6:
	82	case ARPHRD_SIT:
	83	case ARPHRD_IPGRE:
	84	case ARPHRD_VOID:
	85	case ARPHRD_NONE:
	86	ok_push = 0;
	87	break;
	88	default:
	89	ok_push = 1;
	90	break;
	91	}
	92	}
	93
e9ce1cd3 DM	94	pc = tcf_hash_check(parm->index, a, bind, &mirred_hash_info);
e9ce1cd3 DM	95	if (!pc) {
1da177e4 LT	96	if (!parm->ifindex)
1da177e4 LT	97	return -EINVAL;
e9ce1cd3 DM	98	pc = tcf_hash_create(parm->index, est, a, sizeof(*m), bind,
	99	&mirred_idx_gen, &mirred_hash_info);
	100	if (unlikely(!pc))
1da177e4 LT	101	return -ENOMEM;
	102	ret = ACT_P_CREATED;
	103	} else {
	104	if (!ovr) {
e9ce1cd3	105	tcf_mirred_release(to_mirred(pc), bind);
1da177e4 LT	106	return -EEXIST;
	107	}
	108	}
e9ce1cd3	109	m = to_mirred(pc);
1da177e4	110
e9ce1cd3 DM	111	spin_lock_bh(&m->tcf_lock);
	112	m->tcf_action = parm->action;
	113	m->tcfm_eaction = parm->eaction;
1da177e4	114	if (parm->ifindex) {
e9ce1cd3	115	m->tcfm_ifindex = parm->ifindex;
1da177e4	116	if (ret != ACT_P_CREATED)
e9ce1cd3 DM	117	dev_put(m->tcfm_dev);
e9ce1cd3 DM	118	m->tcfm_dev = dev;
1da177e4	119	dev_hold(dev);
e9ce1cd3	120	m->tcfm_ok_push = ok_push;
1da177e4	121	}
e9ce1cd3	122	spin_unlock_bh(&m->tcf_lock);
1da177e4	123	if (ret == ACT_P_CREATED)
e9ce1cd3	124	tcf_hash_insert(pc, &mirred_hash_info);
1da177e4	125
1da177e4 LT	126	return ret;
	127	}
	128
e9ce1cd3	129	static int tcf_mirred_cleanup(struct tc_action *a, int bind)
1da177e4	130	{
e9ce1cd3	131	struct tcf_mirred *m = a->priv;
1da177e4	132
e9ce1cd3 DM	133	if (m)
e9ce1cd3 DM	134	return tcf_mirred_release(m, bind);
1da177e4 LT	135	return 0;
	136	}
	137
e9ce1cd3 DM	138	static int tcf_mirred(struct sk_buff skb, struct tc_action a,
e9ce1cd3 DM	139	struct tcf_result *res)
1da177e4	140	{
e9ce1cd3	141	struct tcf_mirred *m = a->priv;
1da177e4 LT	142	struct net_device *dev;
1da177e4 LT	143	struct sk_buff *skb2 = NULL;
1da177e4 LT	144	u32 at = G_TC_AT(skb->tc_verd);
1da177e4 LT	145
e9ce1cd3	146	spin_lock(&m->tcf_lock);
1da177e4	147
e9ce1cd3 DM	148	dev = m->tcfm_dev;
e9ce1cd3 DM	149	m->tcf_tm.lastuse = jiffies;
1da177e4 LT	150
	151	if (!(dev->flags&IFF_UP) ) {
	152	if (net_ratelimit())
	153	printk("mirred to Houston: device %s is gone!\n",
	154	dev->name);
	155	bad_mirred:
	156	if (skb2 != NULL)
	157	kfree_skb(skb2);
e9ce1cd3 DM	158	m->tcf_qstats.overlimits++;
	159	m->tcf_bstats.bytes += skb->len;
	160	m->tcf_bstats.packets++;
	161	spin_unlock(&m->tcf_lock);
1da177e4 LT	162	/* should we be asking for packet to be dropped?
	163	* may make sense for redirect case only
	164	*/
	165	return TC_ACT_SHOT;
	166	}
	167
	168	skb2 = skb_clone(skb, GFP_ATOMIC);
	169	if (skb2 == NULL)
	170	goto bad_mirred;
e9ce1cd3 DM	171	if (m->tcfm_eaction != TCA_EGRESS_MIRROR &&
e9ce1cd3 DM	172	m->tcfm_eaction != TCA_EGRESS_REDIR) {
1da177e4	173	if (net_ratelimit())
e9ce1cd3 DM	174	printk("tcf_mirred unknown action %d\n",
e9ce1cd3 DM	175	m->tcfm_eaction);
1da177e4 LT	176	goto bad_mirred;
	177	}
	178
e9ce1cd3 DM	179	m->tcf_bstats.bytes += skb2->len;
e9ce1cd3 DM	180	m->tcf_bstats.packets++;
1da177e4	181	if (!(at & AT_EGRESS))
e9ce1cd3	182	if (m->tcfm_ok_push)
1da177e4 LT	183	skb_push(skb2, skb2->dev->hard_header_len);
	184
	185	/* mirror is always swallowed */
e9ce1cd3	186	if (m->tcfm_eaction != TCA_EGRESS_MIRROR)
1da177e4 LT	187	skb2->tc_verd = SET_TC_FROM(skb2->tc_verd, at);
	188
	189	skb2->dev = dev;
c01003c2	190	skb2->iif = skb->dev->ifindex;
1da177e4	191	dev_queue_xmit(skb2);
e9ce1cd3 DM	192	spin_unlock(&m->tcf_lock);
e9ce1cd3 DM	193	return m->tcf_action;
1da177e4 LT	194	}
1da177e4 LT	195
e9ce1cd3	196	static int tcf_mirred_dump(struct sk_buff skb, struct tc_action a, int bind, int ref)
1da177e4	197	{
27a884dc	198	unsigned char *b = skb_tail_pointer(skb);
e9ce1cd3	199	struct tcf_mirred *m = a->priv;
1da177e4	200	struct tc_mirred opt;
1da177e4 LT	201	struct tcf_t t;
1da177e4 LT	202
e9ce1cd3 DM	203	opt.index = m->tcf_index;
	204	opt.action = m->tcf_action;
	205	opt.refcnt = m->tcf_refcnt - ref;
	206	opt.bindcnt = m->tcf_bindcnt - bind;
	207	opt.eaction = m->tcfm_eaction;
	208	opt.ifindex = m->tcfm_ifindex;
1da177e4	209	RTA_PUT(skb, TCA_MIRRED_PARMS, sizeof(opt), &opt);
e9ce1cd3 DM	210	t.install = jiffies_to_clock_t(jiffies - m->tcf_tm.install);
	211	t.lastuse = jiffies_to_clock_t(jiffies - m->tcf_tm.lastuse);
	212	t.expires = jiffies_to_clock_t(m->tcf_tm.expires);
1da177e4 LT	213	RTA_PUT(skb, TCA_MIRRED_TM, sizeof(t), &t);
	214	return skb->len;
	215
e9ce1cd3	216	rtattr_failure:
dc5fc579	217	nlmsg_trim(skb, b);
1da177e4 LT	218	return -1;
	219	}
	220
	221	static struct tc_action_ops act_mirred_ops = {
	222	.kind = "mirred",
e9ce1cd3	223	.hinfo = &mirred_hash_info,
1da177e4 LT	224	.type = TCA_ACT_MIRRED,
	225	.capab = TCA_CAP_NONE,
	226	.owner = THIS_MODULE,
	227	.act = tcf_mirred,
	228	.dump = tcf_mirred_dump,
	229	.cleanup = tcf_mirred_cleanup,
	230	.lookup = tcf_hash_search,
	231	.init = tcf_mirred_init,
	232	.walk = tcf_generic_walker
	233	};
	234
	235	MODULE_AUTHOR("Jamal Hadi Salim(2002)");
	236	MODULE_DESCRIPTION("Device Mirror/redirect actions");
	237	MODULE_LICENSE("GPL");
	238
e9ce1cd3	239	static int __init mirred_init_module(void)
1da177e4 LT	240	{
	241	printk("Mirror/redirect action on\n");
	242	return tcf_register_action(&act_mirred_ops);
	243	}
	244
e9ce1cd3	245	static void __exit mirred_cleanup_module(void)
1da177e4 LT	246	{
	247	tcf_unregister_action(&act_mirred_ops);
	248	}
	249
	250	module_init(mirred_init_module);
	251	module_exit(mirred_cleanup_module);