[linux-2.6-block.git] / net / sched / act_mirred.c

/*
 * net/sched/act_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 <linux/gfp.h>
#include <linux/if_arp.h>
#include <net/net_namespace.h>
#include <net/netlink.h>
#include <net/pkt_sched.h>
#include <linux/tc_act/tc_mirred.h>
#include <net/tc_act/tc_mirred.h>

static LIST_HEAD(mirred_list);

static bool tcf_mirred_is_act_redirect(int action)
{
	return action == TCA_EGRESS_REDIR || action == TCA_INGRESS_REDIR;
}

static bool tcf_mirred_act_wants_ingress(int action)
{
	switch (action) {
	case TCA_EGRESS_REDIR:
	case TCA_EGRESS_MIRROR:
		return false;
	case TCA_INGRESS_REDIR:
	case TCA_INGRESS_MIRROR:
		return true;
	default:
		BUG();
	}
}

static void tcf_mirred_release(struct tc_action *a)
{
	struct tcf_mirred *m = to_mirred(a);
	struct net_device *dev;

	list_del(&m->tcfm_list);
	dev = rtnl_dereference(m->tcfm_dev);
	if (dev)
		dev_put(dev);
}

static const struct nla_policy mirred_policy[TCA_MIRRED_MAX + 1] = {
	[TCA_MIRRED_PARMS]	= { .len = sizeof(struct tc_mirred) },
};

static unsigned int mirred_net_id;
static struct tc_action_ops act_mirred_ops;

static int tcf_mirred_init(struct net *net, struct nlattr *nla,
			   struct nlattr *est, struct tc_action **a, int ovr,
			   int bind)
{
	struct tc_action_net *tn = net_generic(net, mirred_net_id);
	struct nlattr *tb[TCA_MIRRED_MAX + 1];
	bool mac_header_xmit = false;
	struct tc_mirred *parm;
	struct tcf_mirred *m;
	struct net_device *dev;
	bool exists = false;
	int ret;

	if (nla == NULL)
		return -EINVAL;
	ret = nla_parse_nested(tb, TCA_MIRRED_MAX, nla, mirred_policy, NULL);
	if (ret < 0)
		return ret;
	if (tb[TCA_MIRRED_PARMS] == NULL)
		return -EINVAL;
	parm = nla_data(tb[TCA_MIRRED_PARMS]);

	exists = tcf_idr_check(tn, parm->index, a, bind);
	if (exists && bind)
		return 0;

	switch (parm->eaction) {
	case TCA_EGRESS_MIRROR:
	case TCA_EGRESS_REDIR:
	case TCA_INGRESS_REDIR:
	case TCA_INGRESS_MIRROR:
		break;
	default:
		if (exists)
			tcf_idr_release(*a, bind);
		return -EINVAL;
	}
	if (parm->ifindex) {
		dev = __dev_get_by_index(net, parm->ifindex);
		if (dev == NULL) {
			if (exists)
				tcf_idr_release(*a, bind);
			return -ENODEV;
		}
		mac_header_xmit = dev_is_mac_header_xmit(dev);
	} else {
		dev = NULL;
	}

	if (!exists) {
		if (dev == NULL)
			return -EINVAL;
		ret = tcf_idr_create(tn, parm->index, est, a,
				     &act_mirred_ops, bind, true);
		if (ret)
			return ret;
		ret = ACT_P_CREATED;
	} else {
		tcf_idr_release(*a, bind);
		if (!ovr)
			return -EEXIST;
	}
	m = to_mirred(*a);

	ASSERT_RTNL();
	m->tcf_action = parm->action;
	m->tcfm_eaction = parm->eaction;
	if (dev != NULL) {
		if (ret != ACT_P_CREATED)
			dev_put(rcu_dereference_protected(m->tcfm_dev, 1));
		dev_hold(dev);
		rcu_assign_pointer(m->tcfm_dev, dev);
		m->tcfm_mac_header_xmit = mac_header_xmit;
	}

	if (ret == ACT_P_CREATED) {
		list_add(&m->tcfm_list, &mirred_list);
		tcf_idr_insert(tn, *a);
	}

	return ret;
}

static int tcf_mirred(struct sk_buff *skb, const struct tc_action *a,
		      struct tcf_result *res)
{
	struct tcf_mirred *m = to_mirred(a);
	bool m_mac_header_xmit;
	struct net_device *dev;
	struct sk_buff *skb2;
	int retval, err = 0;
	int m_eaction;
	int mac_len;

	tcf_lastuse_update(&m->tcf_tm);
	bstats_cpu_update(this_cpu_ptr(m->common.cpu_bstats), skb);

	rcu_read_lock();
	m_mac_header_xmit = READ_ONCE(m->tcfm_mac_header_xmit);
	m_eaction = READ_ONCE(m->tcfm_eaction);
	retval = READ_ONCE(m->tcf_action);
	dev = rcu_dereference(m->tcfm_dev);
	if (unlikely(!dev)) {
		pr_notice_once("tc mirred: target device is gone\n");
		goto out;
	}

	if (unlikely(!(dev->flags & IFF_UP))) {
		net_notice_ratelimited("tc mirred to Houston: device %s is down\n",
				       dev->name);
		goto out;
	}

	skb2 = skb_clone(skb, GFP_ATOMIC);
	if (!skb2)
		goto out;

	/* If action's target direction differs than filter's direction,
	 * and devices expect a mac header on xmit, then mac push/pull is
	 * needed.
	 */
	if (skb_at_tc_ingress(skb) != tcf_mirred_act_wants_ingress(m_eaction) &&
	    m_mac_header_xmit) {
		if (!skb_at_tc_ingress(skb)) {
			/* caught at egress, act ingress: pull mac */
			mac_len = skb_network_header(skb) - skb_mac_header(skb);
			skb_pull_rcsum(skb2, mac_len);
		} else {
			/* caught at ingress, act egress: push mac */
			skb_push_rcsum(skb2, skb->mac_len);
		}
	}

	/* mirror is always swallowed */
	if (tcf_mirred_is_act_redirect(m_eaction)) {
		skb2->tc_redirected = 1;
		skb2->tc_from_ingress = skb2->tc_at_ingress;
	}

	skb2->skb_iif = skb->dev->ifindex;
	skb2->dev = dev;
	if (!tcf_mirred_act_wants_ingress(m_eaction))
		err = dev_queue_xmit(skb2);
	else
		err = netif_receive_skb(skb2);

	if (err) {
out:
		qstats_overlimit_inc(this_cpu_ptr(m->common.cpu_qstats));
		if (tcf_mirred_is_act_redirect(m_eaction))
			retval = TC_ACT_SHOT;
	}
	rcu_read_unlock();

	return retval;
}

static void tcf_stats_update(struct tc_action *a, u64 bytes, u32 packets,
			     u64 lastuse)
{
	struct tcf_mirred *m = to_mirred(a);
	struct tcf_t *tm = &m->tcf_tm;

	_bstats_cpu_update(this_cpu_ptr(a->cpu_bstats), bytes, packets);
	tm->lastuse = max_t(u64, tm->lastuse, lastuse);
}

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 = to_mirred(a);
	struct net_device *dev = rtnl_dereference(m->tcfm_dev);
	struct tc_mirred opt = {
		.index   = m->tcf_index,
		.action  = m->tcf_action,
		.refcnt  = m->tcf_refcnt - ref,
		.bindcnt = m->tcf_bindcnt - bind,
		.eaction = m->tcfm_eaction,
		.ifindex = dev ? dev->ifindex : 0,
	};
	struct tcf_t t;

	if (nla_put(skb, TCA_MIRRED_PARMS, sizeof(opt), &opt))
		goto nla_put_failure;

	tcf_tm_dump(&t, &m->tcf_tm);
	if (nla_put_64bit(skb, TCA_MIRRED_TM, sizeof(t), &t, TCA_MIRRED_PAD))
		goto nla_put_failure;
	return skb->len;

nla_put_failure:
	nlmsg_trim(skb, b);
	return -1;
}

static int tcf_mirred_walker(struct net *net, struct sk_buff *skb,
			     struct netlink_callback *cb, int type,
			     const struct tc_action_ops *ops)
{
	struct tc_action_net *tn = net_generic(net, mirred_net_id);

	return tcf_generic_walker(tn, skb, cb, type, ops);
}

static int tcf_mirred_search(struct net *net, struct tc_action **a, u32 index)
{
	struct tc_action_net *tn = net_generic(net, mirred_net_id);

	return tcf_idr_search(tn, a, index);
}

static int mirred_device_event(struct notifier_block *unused,
			       unsigned long event, void *ptr)
{
	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
	struct tcf_mirred *m;

	ASSERT_RTNL();
	if (event == NETDEV_UNREGISTER) {
		list_for_each_entry(m, &mirred_list, tcfm_list) {
			if (rcu_access_pointer(m->tcfm_dev) == dev) {
				dev_put(dev);
				/* Note : no rcu grace period necessary, as
				 * net_device are already rcu protected.
				 */
				RCU_INIT_POINTER(m->tcfm_dev, NULL);
			}
		}
	}

	return NOTIFY_DONE;
}

static struct notifier_block mirred_device_notifier = {
	.notifier_call = mirred_device_event,
};

static struct net_device *tcf_mirred_get_dev(const struct tc_action *a)
{
	struct tcf_mirred *m = to_mirred(a);

	return rtnl_dereference(m->tcfm_dev);
}

static struct tc_action_ops act_mirred_ops = {
	.kind		=	"mirred",
	.type		=	TCA_ACT_MIRRED,
	.owner		=	THIS_MODULE,
	.act		=	tcf_mirred,
	.stats_update	=	tcf_stats_update,
	.dump		=	tcf_mirred_dump,
	.cleanup	=	tcf_mirred_release,
	.init		=	tcf_mirred_init,
	.walk		=	tcf_mirred_walker,
	.lookup		=	tcf_mirred_search,
	.size		=	sizeof(struct tcf_mirred),
	.get_dev	=	tcf_mirred_get_dev,
};

static __net_init int mirred_init_net(struct net *net)
{
	struct tc_action_net *tn = net_generic(net, mirred_net_id);

	return tc_action_net_init(tn, &act_mirred_ops);
}

static void __net_exit mirred_exit_net(struct list_head *net_list)
{
	tc_action_net_exit(net_list, mirred_net_id);
}

static struct pernet_operations mirred_net_ops = {
	.init = mirred_init_net,
	.exit_batch = mirred_exit_net,
	.id   = &mirred_net_id,
	.size = sizeof(struct tc_action_net),
};

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

static int __init mirred_init_module(void)
{
	int err = register_netdevice_notifier(&mirred_device_notifier);
	if (err)
		return err;

	pr_info("Mirror/redirect action on\n");
	return tcf_register_action(&act_mirred_ops, &mirred_net_ops);
}

static void __exit mirred_cleanup_module(void)
{
	tcf_unregister_action(&act_mirred_ops, &mirred_net_ops);
	unregister_netdevice_notifier(&mirred_device_notifier);
}

module_init(mirred_init_module);
module_exit(mirred_cleanup_module);
Commit	Line	Data
1da177e4	1	/*
0c6965dd	2	* net/sched/act_mirred.c packet mirroring and redirect actions
1da177e4 LT	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>
5a0e3ad6	23	#include <linux/gfp.h>
c491680f	24	#include <linux/if_arp.h>
881d966b	25	#include <net/net_namespace.h>
dc5fc579	26	#include <net/netlink.h>
1da177e4 LT	27	#include <net/pkt_sched.h>
	28	#include <linux/tc_act/tc_mirred.h>
	29	#include <net/tc_act/tc_mirred.h>
	30
3b87956e	31	static LIST_HEAD(mirred_list);
1da177e4	32
53592b36 SL	33	static bool tcf_mirred_is_act_redirect(int action)
	34	{
	35	return action == TCA_EGRESS_REDIR \|\| action == TCA_INGRESS_REDIR;
	36	}
	37
8dc07fdb	38	static bool tcf_mirred_act_wants_ingress(int action)
53592b36 SL	39	{
	40	switch (action) {
	41	case TCA_EGRESS_REDIR:
	42	case TCA_EGRESS_MIRROR:
8dc07fdb	43	return false;
53592b36 SL	44	case TCA_INGRESS_REDIR:
53592b36 SL	45	case TCA_INGRESS_MIRROR:
8dc07fdb	46	return true;
53592b36 SL	47	default:
	48	BUG();
	49	}
	50	}
	51
9a63b255	52	static void tcf_mirred_release(struct tc_action *a)
1da177e4	53	{
86062033	54	struct tcf_mirred *m = to_mirred(a);
dc327f89	55	struct net_device *dev;
2ee22a90	56
a5b5c958	57	list_del(&m->tcfm_list);
4bee00eb	58	dev = rtnl_dereference(m->tcfm_dev);
2ee22a90 ED	59	if (dev)
2ee22a90 ED	60	dev_put(dev);
1da177e4 LT	61	}
1da177e4 LT	62
53b2bf3f PM	63	static const struct nla_policy mirred_policy[TCA_MIRRED_MAX + 1] = {
	64	[TCA_MIRRED_PARMS] = { .len = sizeof(struct tc_mirred) },
	65	};
	66
c7d03a00	67	static unsigned int mirred_net_id;
a85a970a	68	static struct tc_action_ops act_mirred_ops;
ddf97ccd	69
c1b52739	70	static int tcf_mirred_init(struct net net, struct nlattr nla,
a85a970a	71	struct nlattr est, struct tc_action *a, int ovr,
c1b52739	72	int bind)
1da177e4	73	{
ddf97ccd	74	struct tc_action_net *tn = net_generic(net, mirred_net_id);
7ba699c6	75	struct nlattr *tb[TCA_MIRRED_MAX + 1];
16577923	76	bool mac_header_xmit = false;
1da177e4	77	struct tc_mirred *parm;
e9ce1cd3	78	struct tcf_mirred *m;
b76965e0	79	struct net_device *dev;
b2313077	80	bool exists = false;
16577923	81	int ret;
1da177e4	82
cee63723	83	if (nla == NULL)
1da177e4	84	return -EINVAL;
fceb6435	85	ret = nla_parse_nested(tb, TCA_MIRRED_MAX, nla, mirred_policy, NULL);
b76965e0 CG	86	if (ret < 0)
b76965e0 CG	87	return ret;
53b2bf3f	88	if (tb[TCA_MIRRED_PARMS] == NULL)
1da177e4	89	return -EINVAL;
7ba699c6	90	parm = nla_data(tb[TCA_MIRRED_PARMS]);
87dfbdc6	91
65a206c0	92	exists = tcf_idr_check(tn, parm->index, a, bind);
87dfbdc6 JHS	93	if (exists && bind)
	94	return 0;
	95
b76965e0 CG	96	switch (parm->eaction) {
	97	case TCA_EGRESS_MIRROR:
	98	case TCA_EGRESS_REDIR:
53592b36 SL	99	case TCA_INGRESS_REDIR:
53592b36 SL	100	case TCA_INGRESS_MIRROR:
b76965e0 CG	101	break;
b76965e0 CG	102	default:
87dfbdc6	103	if (exists)
65a206c0	104	tcf_idr_release(*a, bind);
b76965e0 CG	105	return -EINVAL;
b76965e0 CG	106	}
1da177e4	107	if (parm->ifindex) {
c1b52739	108	dev = __dev_get_by_index(net, parm->ifindex);
87dfbdc6 JHS	109	if (dev == NULL) {
87dfbdc6 JHS	110	if (exists)
65a206c0	111	tcf_idr_release(*a, bind);
1da177e4	112	return -ENODEV;
87dfbdc6	113	}
dcf80034	114	mac_header_xmit = dev_is_mac_header_xmit(dev);
b76965e0 CG	115	} else {
b76965e0 CG	116	dev = NULL;
1da177e4 LT	117	}
1da177e4 LT	118
87dfbdc6	119	if (!exists) {
b76965e0	120	if (dev == NULL)
1da177e4	121	return -EINVAL;
65a206c0 CM	122	ret = tcf_idr_create(tn, parm->index, est, a,
65a206c0 CM	123	&act_mirred_ops, bind, true);
86062033 WC	124	if (ret)
86062033 WC	125	return ret;
1da177e4 LT	126	ret = ACT_P_CREATED;
1da177e4 LT	127	} else {
65a206c0	128	tcf_idr_release(*a, bind);
215c90af	129	if (!ovr)
1da177e4	130	return -EEXIST;
1da177e4	131	}
a85a970a	132	m = to_mirred(*a);
1da177e4	133
2ee22a90	134	ASSERT_RTNL();
e9ce1cd3 DM	135	m->tcf_action = parm->action;
e9ce1cd3 DM	136	m->tcfm_eaction = parm->eaction;
b76965e0	137	if (dev != NULL) {
1da177e4	138	if (ret != ACT_P_CREATED)
2ee22a90	139	dev_put(rcu_dereference_protected(m->tcfm_dev, 1));
1da177e4	140	dev_hold(dev);
2ee22a90	141	rcu_assign_pointer(m->tcfm_dev, dev);
16577923	142	m->tcfm_mac_header_xmit = mac_header_xmit;
1da177e4	143	}
2ee22a90	144
3b87956e	145	if (ret == ACT_P_CREATED) {
3b87956e	146	list_add(&m->tcfm_list, &mirred_list);
65a206c0	147	tcf_idr_insert(tn, *a);
3b87956e	148	}
1da177e4	149
1da177e4 LT	150	return ret;
	151	}
	152
dc7f9f6e	153	static int tcf_mirred(struct sk_buff skb, const struct tc_action a,
e9ce1cd3	154	struct tcf_result *res)
1da177e4	155	{
a85a970a	156	struct tcf_mirred *m = to_mirred(a);
53592b36	157	bool m_mac_header_xmit;
1da177e4	158	struct net_device *dev;
feed1f17	159	struct sk_buff *skb2;
53592b36 SL	160	int retval, err = 0;
	161	int m_eaction;
	162	int mac_len;
1da177e4	163
2ee22a90	164	tcf_lastuse_update(&m->tcf_tm);
2ee22a90	165	bstats_cpu_update(this_cpu_ptr(m->common.cpu_bstats), skb);
1da177e4	166
2ee22a90	167	rcu_read_lock();
53592b36 SL	168	m_mac_header_xmit = READ_ONCE(m->tcfm_mac_header_xmit);
53592b36 SL	169	m_eaction = READ_ONCE(m->tcfm_eaction);
2ee22a90 ED	170	retval = READ_ONCE(m->tcf_action);
	171	dev = rcu_dereference(m->tcfm_dev);
	172	if (unlikely(!dev)) {
	173	pr_notice_once("tc mirred: target device is gone\n");
3b87956e	174	goto out;
	175	}
	176
2ee22a90	177	if (unlikely(!(dev->flags & IFF_UP))) {
e87cc472 JP	178	net_notice_ratelimited("tc mirred to Houston: device %s is down\n",
e87cc472 JP	179	dev->name);
feed1f17	180	goto out;
1da177e4 LT	181	}
1da177e4 LT	182
e578d9c0	183	skb2 = skb_clone(skb, GFP_ATOMIC);
2ee22a90	184	if (!skb2)
feed1f17	185	goto out;
1da177e4	186
53592b36 SL	187	/* If action's target direction differs than filter's direction,
	188	* and devices expect a mac header on xmit, then mac push/pull is
	189	* needed.
	190	*/
8dc07fdb	191	if (skb_at_tc_ingress(skb) != tcf_mirred_act_wants_ingress(m_eaction) &&
a5135bcf WB	192	m_mac_header_xmit) {
a5135bcf WB	193	if (!skb_at_tc_ingress(skb)) {
53592b36 SL	194	/* caught at egress, act ingress: pull mac */
	195	mac_len = skb_network_header(skb) - skb_mac_header(skb);
	196	skb_pull_rcsum(skb2, mac_len);
	197	} else {
	198	/* caught at ingress, act egress: push mac */
82a31b92	199	skb_push_rcsum(skb2, skb->mac_len);
53592b36	200	}
feed1f17	201	}
1da177e4 LT	202
1da177e4 LT	203	/* mirror is always swallowed */
bc31c905 WB	204	if (tcf_mirred_is_act_redirect(m_eaction)) {
	205	skb2->tc_redirected = 1;
	206	skb2->tc_from_ingress = skb2->tc_at_ingress;
	207	}
1da177e4	208
8964be4a	209	skb2->skb_iif = skb->dev->ifindex;
210d6de7	210	skb2->dev = dev;
8dc07fdb	211	if (!tcf_mirred_act_wants_ingress(m_eaction))
53592b36 SL	212	err = dev_queue_xmit(skb2);
	213	else
	214	err = netif_receive_skb(skb2);
feed1f17	215
feed1f17	216	if (err) {
2ee22a90 ED	217	out:
2ee22a90 ED	218	qstats_overlimit_inc(this_cpu_ptr(m->common.cpu_qstats));
53592b36	219	if (tcf_mirred_is_act_redirect(m_eaction))
16c0b164	220	retval = TC_ACT_SHOT;
2ee22a90 ED	221	}
2ee22a90 ED	222	rcu_read_unlock();
feed1f17 CG	223
feed1f17 CG	224	return retval;
1da177e4 LT	225	}
1da177e4 LT	226
9798e6fe JK	227	static void tcf_stats_update(struct tc_action *a, u64 bytes, u32 packets,
	228	u64 lastuse)
	229	{
5712bf9c PB	230	struct tcf_mirred *m = to_mirred(a);
	231	struct tcf_t *tm = &m->tcf_tm;
	232
9798e6fe	233	_bstats_cpu_update(this_cpu_ptr(a->cpu_bstats), bytes, packets);
3bb23421	234	tm->lastuse = max_t(u64, tm->lastuse, lastuse);
9798e6fe JK	235	}
9798e6fe JK	236
5a7a5555 JHS	237	static int tcf_mirred_dump(struct sk_buff skb, struct tc_action a, int bind,
5a7a5555 JHS	238	int ref)
1da177e4	239	{
27a884dc	240	unsigned char *b = skb_tail_pointer(skb);
a85a970a	241	struct tcf_mirred *m = to_mirred(a);
9f8a739e	242	struct net_device *dev = rtnl_dereference(m->tcfm_dev);
1c40be12 ED	243	struct tc_mirred opt = {
	244	.index = m->tcf_index,
	245	.action = m->tcf_action,
	246	.refcnt = m->tcf_refcnt - ref,
	247	.bindcnt = m->tcf_bindcnt - bind,
	248	.eaction = m->tcfm_eaction,
9f8a739e	249	.ifindex = dev ? dev->ifindex : 0,
1c40be12	250	};
1da177e4 LT	251	struct tcf_t t;
1da177e4 LT	252
1b34ec43 DM	253	if (nla_put(skb, TCA_MIRRED_PARMS, sizeof(opt), &opt))
1b34ec43 DM	254	goto nla_put_failure;
48d8ee16 JHS	255
48d8ee16 JHS	256	tcf_tm_dump(&t, &m->tcf_tm);
9854518e	257	if (nla_put_64bit(skb, TCA_MIRRED_TM, sizeof(t), &t, TCA_MIRRED_PAD))
1b34ec43	258	goto nla_put_failure;
1da177e4 LT	259	return skb->len;
1da177e4 LT	260
7ba699c6	261	nla_put_failure:
dc5fc579	262	nlmsg_trim(skb, b);
1da177e4 LT	263	return -1;
	264	}
	265
ddf97ccd WC	266	static int tcf_mirred_walker(struct net net, struct sk_buff skb,
ddf97ccd WC	267	struct netlink_callback *cb, int type,
a85a970a	268	const struct tc_action_ops *ops)
ddf97ccd WC	269	{
	270	struct tc_action_net *tn = net_generic(net, mirred_net_id);
	271
a85a970a	272	return tcf_generic_walker(tn, skb, cb, type, ops);
ddf97ccd WC	273	}
ddf97ccd WC	274
a85a970a	275	static int tcf_mirred_search(struct net net, struct tc_action *a, u32 index)
ddf97ccd WC	276	{
	277	struct tc_action_net *tn = net_generic(net, mirred_net_id);
	278
65a206c0	279	return tcf_idr_search(tn, a, index);
ddf97ccd WC	280	}
ddf97ccd WC	281
3b87956e	282	static int mirred_device_event(struct notifier_block *unused,
	283	unsigned long event, void *ptr)
	284	{
351638e7	285	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
3b87956e	286	struct tcf_mirred *m;
3b87956e	287
2ee22a90	288	ASSERT_RTNL();
6bd00b85	289	if (event == NETDEV_UNREGISTER) {
3b87956e	290	list_for_each_entry(m, &mirred_list, tcfm_list) {
2ee22a90	291	if (rcu_access_pointer(m->tcfm_dev) == dev) {
3b87956e	292	dev_put(dev);
2ee22a90 ED	293	/* Note : no rcu grace period necessary, as
	294	* net_device are already rcu protected.
	295	*/
	296	RCU_INIT_POINTER(m->tcfm_dev, NULL);
3b87956e	297	}
3b87956e	298	}
6bd00b85	299	}
3b87956e	300
	301	return NOTIFY_DONE;
	302	}
	303
	304	static struct notifier_block mirred_device_notifier = {
	305	.notifier_call = mirred_device_event,
	306	};
	307
843e79d0	308	static struct net_device tcf_mirred_get_dev(const struct tc_action a)
255cb304	309	{
843e79d0	310	struct tcf_mirred *m = to_mirred(a);
255cb304	311
9f8a739e	312	return rtnl_dereference(m->tcfm_dev);
255cb304 HHZ	313	}
255cb304 HHZ	314
1da177e4 LT	315	static struct tc_action_ops act_mirred_ops = {
	316	.kind = "mirred",
	317	.type = TCA_ACT_MIRRED,
1da177e4 LT	318	.owner = THIS_MODULE,
1da177e4 LT	319	.act = tcf_mirred,
9798e6fe	320	.stats_update = tcf_stats_update,
1da177e4	321	.dump = tcf_mirred_dump,
86062033	322	.cleanup = tcf_mirred_release,
1da177e4	323	.init = tcf_mirred_init,
ddf97ccd WC	324	.walk = tcf_mirred_walker,
ddf97ccd WC	325	.lookup = tcf_mirred_search,
a85a970a	326	.size = sizeof(struct tcf_mirred),
843e79d0	327	.get_dev = tcf_mirred_get_dev,
ddf97ccd WC	328	};
	329
	330	static __net_init int mirred_init_net(struct net *net)
	331	{
	332	struct tc_action_net *tn = net_generic(net, mirred_net_id);
	333
c7e460ce	334	return tc_action_net_init(tn, &act_mirred_ops);
ddf97ccd WC	335	}
ddf97ccd WC	336
039af9c6	337	static void __net_exit mirred_exit_net(struct list_head *net_list)
ddf97ccd	338	{
039af9c6	339	tc_action_net_exit(net_list, mirred_net_id);
ddf97ccd WC	340	}
	341
	342	static struct pernet_operations mirred_net_ops = {
	343	.init = mirred_init_net,
039af9c6	344	.exit_batch = mirred_exit_net,
ddf97ccd WC	345	.id = &mirred_net_id,
ddf97ccd WC	346	.size = sizeof(struct tc_action_net),
1da177e4 LT	347	};
	348
	349	MODULE_AUTHOR("Jamal Hadi Salim(2002)");
	350	MODULE_DESCRIPTION("Device Mirror/redirect actions");
	351	MODULE_LICENSE("GPL");
	352
e9ce1cd3	353	static int __init mirred_init_module(void)
1da177e4	354	{
3b87956e	355	int err = register_netdevice_notifier(&mirred_device_notifier);
	356	if (err)
	357	return err;
	358
6ff9c364	359	pr_info("Mirror/redirect action on\n");
ddf97ccd	360	return tcf_register_action(&act_mirred_ops, &mirred_net_ops);
1da177e4 LT	361	}
1da177e4 LT	362
e9ce1cd3	363	static void __exit mirred_cleanup_module(void)
1da177e4	364	{
ddf97ccd	365	tcf_unregister_action(&act_mirred_ops, &mirred_net_ops);
568a153a	366	unregister_netdevice_notifier(&mirred_device_notifier);
1da177e4 LT	367	}
	368
	369	module_init(mirred_init_module);
	370	module_exit(mirred_cleanup_module);