[mirror_ubuntu-artful-kernel.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>

#define MIRRED_TAB_MASK     7
static LIST_HEAD(mirred_list);
static DEFINE_SPINLOCK(mirred_list_lock);

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, int bind)
{
	struct tcf_mirred *m = to_mirred(a);
	struct net_device *dev;

	/* We could be called either in a RCU callback or with RTNL lock held. */
	spin_lock_bh(&mirred_list_lock);
	list_del(&m->tcfm_list);
	dev = rcu_dereference_protected(m->tcfm_dev, 1);
	if (dev)
		dev_put(dev);
	spin_unlock_bh(&mirred_list_lock);
}

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_hash_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_hash_release(*a, bind);
		return -EINVAL;
	}
	if (parm->ifindex) {
		dev = __dev_get_by_index(net, parm->ifindex);
		if (dev == NULL) {
			if (exists)
				tcf_hash_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_hash_create(tn, parm->index, est, a,
				      &act_mirred_ops, bind, true);
		if (ret)
			return ret;
		ret = ACT_P_CREATED;
	} else {
		tcf_hash_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) {
		m->tcfm_ifindex = parm->ifindex;
		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) {
		spin_lock_bh(&mirred_list_lock);
		list_add(&m->tcfm_list, &mirred_list);
		spin_unlock_bh(&mirred_list_lock);
		tcf_hash_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 = 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 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 = m->tcfm_ifindex,
	};
	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_hash_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) {
		spin_lock_bh(&mirred_list_lock);
		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);
			}
		}
		spin_unlock_bh(&mirred_list_lock);
	}

	return NOTIFY_DONE;
}

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

static int tcf_mirred_device(const struct tc_action *a, struct net *net,
			     struct net_device **mirred_dev)
{
	int ifindex = tcf_mirred_ifindex(a);

	*mirred_dev = __dev_get_by_index(net, ifindex);
	if (!*mirred_dev)
		return -EINVAL;
	return 0;
}

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_device,
};

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, MIRRED_TAB_MASK);
}

static void __net_exit mirred_exit_net(struct net *net)
{
	struct tc_action_net *tn = net_generic(net, mirred_net_id);

	tc_action_net_exit(tn);
}

static struct pernet_operations mirred_net_ops = {
	.init = mirred_init_net,
	.exit = 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
e9ce1cd3	31	#define MIRRED_TAB_MASK 7
3b87956e	32	static LIST_HEAD(mirred_list);
6bd00b85	33	static DEFINE_SPINLOCK(mirred_list_lock);
1da177e4	34
53592b36 SL	35	static bool tcf_mirred_is_act_redirect(int action)
	36	{
	37	return action == TCA_EGRESS_REDIR \|\| action == TCA_INGRESS_REDIR;
	38	}
	39
8dc07fdb	40	static bool tcf_mirred_act_wants_ingress(int action)
53592b36 SL	41	{
	42	switch (action) {
	43	case TCA_EGRESS_REDIR:
	44	case TCA_EGRESS_MIRROR:
8dc07fdb	45	return false;
53592b36 SL	46	case TCA_INGRESS_REDIR:
53592b36 SL	47	case TCA_INGRESS_MIRROR:
8dc07fdb	48	return true;
53592b36 SL	49	default:
	50	BUG();
	51	}
	52	}
	53
a5b5c958	54	static void tcf_mirred_release(struct tc_action *a, int bind)
1da177e4	55	{
86062033	56	struct tcf_mirred *m = to_mirred(a);
dc327f89	57	struct net_device *dev;
2ee22a90	58
6bd00b85 WC	59	/* We could be called either in a RCU callback or with RTNL lock held. */
6bd00b85 WC	60	spin_lock_bh(&mirred_list_lock);
a5b5c958	61	list_del(&m->tcfm_list);
dc327f89	62	dev = rcu_dereference_protected(m->tcfm_dev, 1);
2ee22a90 ED	63	if (dev)
2ee22a90 ED	64	dev_put(dev);
dc327f89	65	spin_unlock_bh(&mirred_list_lock);
1da177e4 LT	66	}
1da177e4 LT	67
53b2bf3f PM	68	static const struct nla_policy mirred_policy[TCA_MIRRED_MAX + 1] = {
	69	[TCA_MIRRED_PARMS] = { .len = sizeof(struct tc_mirred) },
	70	};
	71
c7d03a00	72	static unsigned int mirred_net_id;
a85a970a	73	static struct tc_action_ops act_mirred_ops;
ddf97ccd	74
c1b52739	75	static int tcf_mirred_init(struct net net, struct nlattr nla,
a85a970a	76	struct nlattr est, struct tc_action *a, int ovr,
c1b52739	77	int bind)
1da177e4	78	{
ddf97ccd	79	struct tc_action_net *tn = net_generic(net, mirred_net_id);
7ba699c6	80	struct nlattr *tb[TCA_MIRRED_MAX + 1];
16577923	81	bool mac_header_xmit = false;
1da177e4	82	struct tc_mirred *parm;
e9ce1cd3	83	struct tcf_mirred *m;
b76965e0	84	struct net_device *dev;
b2313077	85	bool exists = false;
16577923	86	int ret;
1da177e4	87
cee63723	88	if (nla == NULL)
1da177e4	89	return -EINVAL;
fceb6435	90	ret = nla_parse_nested(tb, TCA_MIRRED_MAX, nla, mirred_policy, NULL);
b76965e0 CG	91	if (ret < 0)
b76965e0 CG	92	return ret;
53b2bf3f	93	if (tb[TCA_MIRRED_PARMS] == NULL)
1da177e4	94	return -EINVAL;
7ba699c6	95	parm = nla_data(tb[TCA_MIRRED_PARMS]);
87dfbdc6 JHS	96
	97	exists = tcf_hash_check(tn, parm->index, a, bind);
	98	if (exists && bind)
	99	return 0;
	100
b76965e0 CG	101	switch (parm->eaction) {
	102	case TCA_EGRESS_MIRROR:
	103	case TCA_EGRESS_REDIR:
53592b36 SL	104	case TCA_INGRESS_REDIR:
53592b36 SL	105	case TCA_INGRESS_MIRROR:
b76965e0 CG	106	break;
b76965e0 CG	107	default:
87dfbdc6	108	if (exists)
a85a970a	109	tcf_hash_release(*a, bind);
b76965e0 CG	110	return -EINVAL;
b76965e0 CG	111	}
1da177e4	112	if (parm->ifindex) {
c1b52739	113	dev = __dev_get_by_index(net, parm->ifindex);
87dfbdc6 JHS	114	if (dev == NULL) {
87dfbdc6 JHS	115	if (exists)
a85a970a	116	tcf_hash_release(*a, bind);
1da177e4	117	return -ENODEV;
87dfbdc6	118	}
dcf80034	119	mac_header_xmit = dev_is_mac_header_xmit(dev);
b76965e0 CG	120	} else {
b76965e0 CG	121	dev = NULL;
1da177e4 LT	122	}
1da177e4 LT	123
87dfbdc6	124	if (!exists) {
b76965e0	125	if (dev == NULL)
1da177e4	126	return -EINVAL;
ddf97ccd	127	ret = tcf_hash_create(tn, parm->index, est, a,
a85a970a	128	&act_mirred_ops, bind, true);
86062033 WC	129	if (ret)
86062033 WC	130	return ret;
1da177e4 LT	131	ret = ACT_P_CREATED;
1da177e4 LT	132	} else {
a85a970a	133	tcf_hash_release(*a, bind);
215c90af	134	if (!ovr)
1da177e4	135	return -EEXIST;
1da177e4	136	}
a85a970a	137	m = to_mirred(*a);
1da177e4	138
2ee22a90	139	ASSERT_RTNL();
e9ce1cd3 DM	140	m->tcf_action = parm->action;
e9ce1cd3 DM	141	m->tcfm_eaction = parm->eaction;
b76965e0	142	if (dev != NULL) {
e9ce1cd3	143	m->tcfm_ifindex = parm->ifindex;
1da177e4	144	if (ret != ACT_P_CREATED)
2ee22a90	145	dev_put(rcu_dereference_protected(m->tcfm_dev, 1));
1da177e4	146	dev_hold(dev);
2ee22a90	147	rcu_assign_pointer(m->tcfm_dev, dev);
16577923	148	m->tcfm_mac_header_xmit = mac_header_xmit;
1da177e4	149	}
2ee22a90	150
3b87956e	151	if (ret == ACT_P_CREATED) {
6bd00b85	152	spin_lock_bh(&mirred_list_lock);
3b87956e	153	list_add(&m->tcfm_list, &mirred_list);
6bd00b85	154	spin_unlock_bh(&mirred_list_lock);
a85a970a	155	tcf_hash_insert(tn, *a);
3b87956e	156	}
1da177e4	157
1da177e4 LT	158	return ret;
	159	}
	160
dc7f9f6e	161	static int tcf_mirred(struct sk_buff skb, const struct tc_action a,
e9ce1cd3	162	struct tcf_result *res)
1da177e4	163	{
a85a970a	164	struct tcf_mirred *m = to_mirred(a);
53592b36	165	bool m_mac_header_xmit;
1da177e4	166	struct net_device *dev;
feed1f17	167	struct sk_buff *skb2;
53592b36 SL	168	int retval, err = 0;
	169	int m_eaction;
	170	int mac_len;
1da177e4	171
2ee22a90	172	tcf_lastuse_update(&m->tcf_tm);
2ee22a90	173	bstats_cpu_update(this_cpu_ptr(m->common.cpu_bstats), skb);
1da177e4	174
2ee22a90	175	rcu_read_lock();
53592b36 SL	176	m_mac_header_xmit = READ_ONCE(m->tcfm_mac_header_xmit);
53592b36 SL	177	m_eaction = READ_ONCE(m->tcfm_eaction);
2ee22a90 ED	178	retval = READ_ONCE(m->tcf_action);
	179	dev = rcu_dereference(m->tcfm_dev);
	180	if (unlikely(!dev)) {
	181	pr_notice_once("tc mirred: target device is gone\n");
3b87956e	182	goto out;
	183	}
	184
2ee22a90	185	if (unlikely(!(dev->flags & IFF_UP))) {
e87cc472 JP	186	net_notice_ratelimited("tc mirred to Houston: device %s is down\n",
e87cc472 JP	187	dev->name);
feed1f17	188	goto out;
1da177e4 LT	189	}
1da177e4 LT	190
e578d9c0	191	skb2 = skb_clone(skb, GFP_ATOMIC);
2ee22a90	192	if (!skb2)
feed1f17	193	goto out;
1da177e4	194
53592b36 SL	195	/* If action's target direction differs than filter's direction,
	196	* and devices expect a mac header on xmit, then mac push/pull is
	197	* needed.
	198	*/
8dc07fdb	199	if (skb_at_tc_ingress(skb) != tcf_mirred_act_wants_ingress(m_eaction) &&
a5135bcf WB	200	m_mac_header_xmit) {
a5135bcf WB	201	if (!skb_at_tc_ingress(skb)) {
53592b36 SL	202	/* caught at egress, act ingress: pull mac */
	203	mac_len = skb_network_header(skb) - skb_mac_header(skb);
	204	skb_pull_rcsum(skb2, mac_len);
	205	} else {
	206	/* caught at ingress, act egress: push mac */
82a31b92	207	skb_push_rcsum(skb2, skb->mac_len);
53592b36	208	}
feed1f17	209	}
1da177e4 LT	210
1da177e4 LT	211	/* mirror is always swallowed */
bc31c905 WB	212	if (tcf_mirred_is_act_redirect(m_eaction)) {
	213	skb2->tc_redirected = 1;
	214	skb2->tc_from_ingress = skb2->tc_at_ingress;
	215	}
1da177e4	216
8964be4a	217	skb2->skb_iif = skb->dev->ifindex;
210d6de7	218	skb2->dev = dev;
8dc07fdb	219	if (!tcf_mirred_act_wants_ingress(m_eaction))
53592b36 SL	220	err = dev_queue_xmit(skb2);
	221	else
	222	err = netif_receive_skb(skb2);
feed1f17	223
feed1f17	224	if (err) {
2ee22a90 ED	225	out:
2ee22a90 ED	226	qstats_overlimit_inc(this_cpu_ptr(m->common.cpu_qstats));
53592b36	227	if (tcf_mirred_is_act_redirect(m_eaction))
16c0b164	228	retval = TC_ACT_SHOT;
2ee22a90 ED	229	}
2ee22a90 ED	230	rcu_read_unlock();
feed1f17 CG	231
feed1f17 CG	232	return retval;
1da177e4 LT	233	}
1da177e4 LT	234
9798e6fe JK	235	static void tcf_stats_update(struct tc_action *a, u64 bytes, u32 packets,
	236	u64 lastuse)
	237	{
5712bf9c PB	238	struct tcf_mirred *m = to_mirred(a);
	239	struct tcf_t *tm = &m->tcf_tm;
	240
9798e6fe	241	_bstats_cpu_update(this_cpu_ptr(a->cpu_bstats), bytes, packets);
5712bf9c	242	tm->lastuse = lastuse;
9798e6fe JK	243	}
9798e6fe JK	244
5a7a5555 JHS	245	static int tcf_mirred_dump(struct sk_buff skb, struct tc_action a, int bind,
5a7a5555 JHS	246	int ref)
1da177e4	247	{
27a884dc	248	unsigned char *b = skb_tail_pointer(skb);
a85a970a	249	struct tcf_mirred *m = to_mirred(a);
1c40be12 ED	250	struct tc_mirred opt = {
	251	.index = m->tcf_index,
	252	.action = m->tcf_action,
	253	.refcnt = m->tcf_refcnt - ref,
	254	.bindcnt = m->tcf_bindcnt - bind,
	255	.eaction = m->tcfm_eaction,
	256	.ifindex = m->tcfm_ifindex,
	257	};
1da177e4 LT	258	struct tcf_t t;
1da177e4 LT	259
1b34ec43 DM	260	if (nla_put(skb, TCA_MIRRED_PARMS, sizeof(opt), &opt))
1b34ec43 DM	261	goto nla_put_failure;
48d8ee16 JHS	262
48d8ee16 JHS	263	tcf_tm_dump(&t, &m->tcf_tm);
9854518e	264	if (nla_put_64bit(skb, TCA_MIRRED_TM, sizeof(t), &t, TCA_MIRRED_PAD))
1b34ec43	265	goto nla_put_failure;
1da177e4 LT	266	return skb->len;
1da177e4 LT	267
7ba699c6	268	nla_put_failure:
dc5fc579	269	nlmsg_trim(skb, b);
1da177e4 LT	270	return -1;
	271	}
	272
ddf97ccd WC	273	static int tcf_mirred_walker(struct net net, struct sk_buff skb,
ddf97ccd WC	274	struct netlink_callback *cb, int type,
a85a970a	275	const struct tc_action_ops *ops)
ddf97ccd WC	276	{
	277	struct tc_action_net *tn = net_generic(net, mirred_net_id);
	278
a85a970a	279	return tcf_generic_walker(tn, skb, cb, type, ops);
ddf97ccd WC	280	}
ddf97ccd WC	281
a85a970a	282	static int tcf_mirred_search(struct net net, struct tc_action *a, u32 index)
ddf97ccd WC	283	{
	284	struct tc_action_net *tn = net_generic(net, mirred_net_id);
	285
	286	return tcf_hash_search(tn, a, index);
	287	}
	288
3b87956e	289	static int mirred_device_event(struct notifier_block *unused,
	290	unsigned long event, void *ptr)
	291	{
351638e7	292	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
3b87956e	293	struct tcf_mirred *m;
3b87956e	294
2ee22a90	295	ASSERT_RTNL();
6bd00b85 WC	296	if (event == NETDEV_UNREGISTER) {
6bd00b85 WC	297	spin_lock_bh(&mirred_list_lock);
3b87956e	298	list_for_each_entry(m, &mirred_list, tcfm_list) {
2ee22a90	299	if (rcu_access_pointer(m->tcfm_dev) == dev) {
3b87956e	300	dev_put(dev);
2ee22a90 ED	301	/* Note : no rcu grace period necessary, as
	302	* net_device are already rcu protected.
	303	*/
	304	RCU_INIT_POINTER(m->tcfm_dev, NULL);
3b87956e	305	}
3b87956e	306	}
6bd00b85 WC	307	spin_unlock_bh(&mirred_list_lock);
6bd00b85 WC	308	}
3b87956e	309
	310	return NOTIFY_DONE;
	311	}
	312
	313	static struct notifier_block mirred_device_notifier = {
	314	.notifier_call = mirred_device_event,
	315	};
	316
255cb304 HHZ	317	static int tcf_mirred_device(const struct tc_action a, struct net net,
	318	struct net_device **mirred_dev)
	319	{
	320	int ifindex = tcf_mirred_ifindex(a);
	321
	322	*mirred_dev = __dev_get_by_index(net, ifindex);
548ed722	323	if (!*mirred_dev)
255cb304 HHZ	324	return -EINVAL;
	325	return 0;
	326	}
	327
1da177e4 LT	328	static struct tc_action_ops act_mirred_ops = {
	329	.kind = "mirred",
	330	.type = TCA_ACT_MIRRED,
1da177e4 LT	331	.owner = THIS_MODULE,
1da177e4 LT	332	.act = tcf_mirred,
9798e6fe	333	.stats_update = tcf_stats_update,
1da177e4	334	.dump = tcf_mirred_dump,
86062033	335	.cleanup = tcf_mirred_release,
1da177e4	336	.init = tcf_mirred_init,
ddf97ccd WC	337	.walk = tcf_mirred_walker,
ddf97ccd WC	338	.lookup = tcf_mirred_search,
a85a970a	339	.size = sizeof(struct tcf_mirred),
255cb304	340	.get_dev = tcf_mirred_device,
ddf97ccd WC	341	};
	342
	343	static __net_init int mirred_init_net(struct net *net)
	344	{
	345	struct tc_action_net *tn = net_generic(net, mirred_net_id);
	346
	347	return tc_action_net_init(tn, &act_mirred_ops, MIRRED_TAB_MASK);
	348	}
	349
	350	static void __net_exit mirred_exit_net(struct net *net)
	351	{
	352	struct tc_action_net *tn = net_generic(net, mirred_net_id);
	353
	354	tc_action_net_exit(tn);
	355	}
	356
	357	static struct pernet_operations mirred_net_ops = {
	358	.init = mirred_init_net,
	359	.exit = mirred_exit_net,
	360	.id = &mirred_net_id,
	361	.size = sizeof(struct tc_action_net),
1da177e4 LT	362	};
	363
	364	MODULE_AUTHOR("Jamal Hadi Salim(2002)");
	365	MODULE_DESCRIPTION("Device Mirror/redirect actions");
	366	MODULE_LICENSE("GPL");
	367
e9ce1cd3	368	static int __init mirred_init_module(void)
1da177e4	369	{
3b87956e	370	int err = register_netdevice_notifier(&mirred_device_notifier);
	371	if (err)
	372	return err;
	373
6ff9c364	374	pr_info("Mirror/redirect action on\n");
ddf97ccd	375	return tcf_register_action(&act_mirred_ops, &mirred_net_ops);
1da177e4 LT	376	}
1da177e4 LT	377
e9ce1cd3	378	static void __exit mirred_cleanup_module(void)
1da177e4	379	{
ddf97ccd	380	tcf_unregister_action(&act_mirred_ops, &mirred_net_ops);
568a153a	381	unregister_netdevice_notifier(&mirred_device_notifier);
1da177e4 LT	382	}
	383
	384	module_init(mirred_init_module);
	385	module_exit(mirred_cleanup_module);