[linux-block.git] / net / sched / act_ipt.c

// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * net/sched/act_ipt.c		iptables target interface
 *
 *TODO: Add other tables. For now we only support the ipv4 table targets
 *
 * Copyright:	Jamal Hadi Salim (2002-13)
 */

#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/slab.h>
#include <net/netlink.h>
#include <net/pkt_sched.h>
#include <linux/tc_act/tc_ipt.h>
#include <net/tc_act/tc_ipt.h>
#include <net/tc_wrapper.h>
#include <net/ip.h>

#include <linux/netfilter_ipv4/ip_tables.h>


static struct tc_action_ops act_ipt_ops;
static struct tc_action_ops act_xt_ops;

static int ipt_init_target(struct net *net, struct xt_entry_target *t,
			   char *table, unsigned int hook)
{
	struct xt_tgchk_param par;
	struct xt_target *target;
	struct ipt_entry e = {};
	int ret = 0;

	target = xt_request_find_target(AF_INET, t->u.user.name,
					t->u.user.revision);
	if (IS_ERR(target))
		return PTR_ERR(target);

	t->u.kernel.target = target;
	memset(&par, 0, sizeof(par));
	par.net       = net;
	par.table     = table;
	par.entryinfo = &e;
	par.target    = target;
	par.targinfo  = t->data;
	par.hook_mask = 1 << hook;
	par.family    = NFPROTO_IPV4;

	ret = xt_check_target(&par, t->u.target_size - sizeof(*t), 0, false);
	if (ret < 0) {
		module_put(t->u.kernel.target->me);
		return ret;
	}
	return 0;
}

static void ipt_destroy_target(struct xt_entry_target *t, struct net *net)
{
	struct xt_tgdtor_param par = {
		.target   = t->u.kernel.target,
		.targinfo = t->data,
		.family   = NFPROTO_IPV4,
		.net      = net,
	};
	if (par.target->destroy != NULL)
		par.target->destroy(&par);
	module_put(par.target->me);
}

static void tcf_ipt_release(struct tc_action *a)
{
	struct tcf_ipt *ipt = to_ipt(a);

	if (ipt->tcfi_t) {
		ipt_destroy_target(ipt->tcfi_t, a->idrinfo->net);
		kfree(ipt->tcfi_t);
	}
	kfree(ipt->tcfi_tname);
}

static const struct nla_policy ipt_policy[TCA_IPT_MAX + 1] = {
	[TCA_IPT_TABLE]	= { .type = NLA_STRING, .len = IFNAMSIZ },
	[TCA_IPT_HOOK]	= NLA_POLICY_RANGE(NLA_U32, NF_INET_PRE_ROUTING,
					   NF_INET_NUMHOOKS),
	[TCA_IPT_INDEX]	= { .type = NLA_U32 },
	[TCA_IPT_TARG]	= { .len = sizeof(struct xt_entry_target) },
};

static int __tcf_ipt_init(struct net *net, unsigned int id, struct nlattr *nla,
			  struct nlattr *est, struct tc_action **a,
			  const struct tc_action_ops *ops,
			  struct tcf_proto *tp, u32 flags)
{
	struct tc_action_net *tn = net_generic(net, id);
	bool bind = flags & TCA_ACT_FLAGS_BIND;
	struct nlattr *tb[TCA_IPT_MAX + 1];
	struct tcf_ipt *ipt;
	struct xt_entry_target *td, *t;
	char *tname;
	bool exists = false;
	int ret = 0, err;
	u32 hook = 0;
	u32 index = 0;

	if (nla == NULL)
		return -EINVAL;

	err = nla_parse_nested_deprecated(tb, TCA_IPT_MAX, nla, ipt_policy,
					  NULL);
	if (err < 0)
		return err;

	if (tb[TCA_IPT_INDEX] != NULL)
		index = nla_get_u32(tb[TCA_IPT_INDEX]);

	err = tcf_idr_check_alloc(tn, &index, a, bind);
	if (err < 0)
		return err;
	exists = err;
	if (exists && bind)
		return 0;

	if (tb[TCA_IPT_HOOK] == NULL || tb[TCA_IPT_TARG] == NULL) {
		if (exists)
			tcf_idr_release(*a, bind);
		else
			tcf_idr_cleanup(tn, index);
		return -EINVAL;
	}

	td = (struct xt_entry_target *)nla_data(tb[TCA_IPT_TARG]);
	if (nla_len(tb[TCA_IPT_TARG]) != td->u.target_size) {
		if (exists)
			tcf_idr_release(*a, bind);
		else
			tcf_idr_cleanup(tn, index);
		return -EINVAL;
	}

	if (!exists) {
		ret = tcf_idr_create(tn, index, est, a, ops, bind,
				     false, flags);
		if (ret) {
			tcf_idr_cleanup(tn, index);
			return ret;
		}
		ret = ACT_P_CREATED;
	} else {
		if (bind)/* dont override defaults */
			return 0;

		if (!(flags & TCA_ACT_FLAGS_REPLACE)) {
			tcf_idr_release(*a, bind);
			return -EEXIST;
		}
	}

	err = -EINVAL;
	hook = nla_get_u32(tb[TCA_IPT_HOOK]);
	switch (hook) {
	case NF_INET_PRE_ROUTING:
		break;
	case NF_INET_POST_ROUTING:
		break;
	default:
		goto err1;
	}

	if (tb[TCA_IPT_TABLE]) {
		/* mangle only for now */
		if (nla_strcmp(tb[TCA_IPT_TABLE], "mangle"))
			goto err1;
	}

	tname = kstrdup("mangle", GFP_KERNEL);
	if (unlikely(!tname))
		goto err1;

	t = kmemdup(td, td->u.target_size, GFP_KERNEL);
	if (unlikely(!t))
		goto err2;

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

	ipt = to_ipt(*a);

	spin_lock_bh(&ipt->tcf_lock);
	if (ret != ACT_P_CREATED) {
		ipt_destroy_target(ipt->tcfi_t, net);
		kfree(ipt->tcfi_tname);
		kfree(ipt->tcfi_t);
	}
	ipt->tcfi_tname = tname;
	ipt->tcfi_t     = t;
	ipt->tcfi_hook  = hook;
	spin_unlock_bh(&ipt->tcf_lock);
	return ret;

err3:
	kfree(t);
err2:
	kfree(tname);
err1:
	tcf_idr_release(*a, bind);
	return err;
}

static int tcf_ipt_init(struct net *net, struct nlattr *nla,
			struct nlattr *est, struct tc_action **a,
			struct tcf_proto *tp,
			u32 flags, struct netlink_ext_ack *extack)
{
	return __tcf_ipt_init(net, act_ipt_ops.net_id, nla, est,
			      a, &act_ipt_ops, tp, flags);
}

static int tcf_xt_init(struct net *net, struct nlattr *nla,
		       struct nlattr *est, struct tc_action **a,
		       struct tcf_proto *tp,
		       u32 flags, struct netlink_ext_ack *extack)
{
	return __tcf_ipt_init(net, act_xt_ops.net_id, nla, est,
			      a, &act_xt_ops, tp, flags);
}

static bool tcf_ipt_act_check(struct sk_buff *skb)
{
	const struct iphdr *iph;
	unsigned int nhoff, len;

	if (!pskb_may_pull(skb, sizeof(struct iphdr)))
		return false;

	nhoff = skb_network_offset(skb);
	iph = ip_hdr(skb);
	if (iph->ihl < 5 || iph->version != 4)
		return false;

	len = skb_ip_totlen(skb);
	if (skb->len < nhoff + len || len < (iph->ihl * 4u))
		return false;

	return pskb_may_pull(skb, iph->ihl * 4u);
}

TC_INDIRECT_SCOPE int tcf_ipt_act(struct sk_buff *skb,
				  const struct tc_action *a,
				  struct tcf_result *res)
{
	char saved_cb[sizeof_field(struct sk_buff, cb)];
	int ret = 0, result = 0;
	struct tcf_ipt *ipt = to_ipt(a);
	struct xt_action_param par;
	struct nf_hook_state state = {
		.net	= dev_net(skb->dev),
		.in	= skb->dev,
		.hook	= ipt->tcfi_hook,
		.pf	= NFPROTO_IPV4,
	};

	if (skb_protocol(skb, false) != htons(ETH_P_IP))
		return TC_ACT_UNSPEC;

	if (skb_unclone(skb, GFP_ATOMIC))
		return TC_ACT_UNSPEC;

	if (!tcf_ipt_act_check(skb))
		return TC_ACT_UNSPEC;

	if (state.hook == NF_INET_POST_ROUTING) {
		if (!skb_dst(skb))
			return TC_ACT_UNSPEC;

		state.out = skb->dev;
	}

	memcpy(saved_cb, skb->cb, sizeof(saved_cb));

	spin_lock(&ipt->tcf_lock);

	tcf_lastuse_update(&ipt->tcf_tm);
	bstats_update(&ipt->tcf_bstats, skb);

	/* yes, we have to worry about both in and out dev
	 * worry later - danger - this API seems to have changed
	 * from earlier kernels
	 */
	par.state    = &state;
	par.target   = ipt->tcfi_t->u.kernel.target;
	par.targinfo = ipt->tcfi_t->data;

	memset(IPCB(skb), 0, sizeof(struct inet_skb_parm));

	ret = par.target->target(skb, &par);

	switch (ret) {
	case NF_ACCEPT:
		result = TC_ACT_OK;
		break;
	case NF_DROP:
		result = TC_ACT_SHOT;
		ipt->tcf_qstats.drops++;
		break;
	case XT_CONTINUE:
		result = TC_ACT_PIPE;
		break;
	default:
		net_notice_ratelimited("tc filter: Bogus netfilter code %d assume ACCEPT\n",
				       ret);
		result = TC_ACT_OK;
		break;
	}
	spin_unlock(&ipt->tcf_lock);

	memcpy(skb->cb, saved_cb, sizeof(skb->cb));

	return result;

}

static int tcf_ipt_dump(struct sk_buff *skb, struct tc_action *a, int bind,
			int ref)
{
	unsigned char *b = skb_tail_pointer(skb);
	struct tcf_ipt *ipt = to_ipt(a);
	struct xt_entry_target *t;
	struct tcf_t tm;
	struct tc_cnt c;

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

	spin_lock_bh(&ipt->tcf_lock);
	t = kmemdup(ipt->tcfi_t, ipt->tcfi_t->u.user.target_size, GFP_ATOMIC);
	if (unlikely(!t))
		goto nla_put_failure;

	c.bindcnt = atomic_read(&ipt->tcf_bindcnt) - bind;
	c.refcnt = refcount_read(&ipt->tcf_refcnt) - ref;
	strcpy(t->u.user.name, ipt->tcfi_t->u.kernel.target->name);

	if (nla_put(skb, TCA_IPT_TARG, ipt->tcfi_t->u.user.target_size, t) ||
	    nla_put_u32(skb, TCA_IPT_INDEX, ipt->tcf_index) ||
	    nla_put_u32(skb, TCA_IPT_HOOK, ipt->tcfi_hook) ||
	    nla_put(skb, TCA_IPT_CNT, sizeof(struct tc_cnt), &c) ||
	    nla_put_string(skb, TCA_IPT_TABLE, ipt->tcfi_tname))
		goto nla_put_failure;

	tcf_tm_dump(&tm, &ipt->tcf_tm);
	if (nla_put_64bit(skb, TCA_IPT_TM, sizeof(tm), &tm, TCA_IPT_PAD))
		goto nla_put_failure;

	spin_unlock_bh(&ipt->tcf_lock);
	kfree(t);
	return skb->len;

nla_put_failure:
	spin_unlock_bh(&ipt->tcf_lock);
	nlmsg_trim(skb, b);
	kfree(t);
	return -1;
}

static struct tc_action_ops act_ipt_ops = {
	.kind		=	"ipt",
	.id		=	TCA_ID_IPT,
	.owner		=	THIS_MODULE,
	.act		=	tcf_ipt_act,
	.dump		=	tcf_ipt_dump,
	.cleanup	=	tcf_ipt_release,
	.init		=	tcf_ipt_init,
	.size		=	sizeof(struct tcf_ipt),
};

static __net_init int ipt_init_net(struct net *net)
{
	struct tc_action_net *tn = net_generic(net, act_ipt_ops.net_id);

	return tc_action_net_init(net, tn, &act_ipt_ops);
}

static void __net_exit ipt_exit_net(struct list_head *net_list)
{
	tc_action_net_exit(net_list, act_ipt_ops.net_id);
}

static struct pernet_operations ipt_net_ops = {
	.init = ipt_init_net,
	.exit_batch = ipt_exit_net,
	.id   = &act_ipt_ops.net_id,
	.size = sizeof(struct tc_action_net),
};

static struct tc_action_ops act_xt_ops = {
	.kind		=	"xt",
	.id		=	TCA_ID_XT,
	.owner		=	THIS_MODULE,
	.act		=	tcf_ipt_act,
	.dump		=	tcf_ipt_dump,
	.cleanup	=	tcf_ipt_release,
	.init		=	tcf_xt_init,
	.size		=	sizeof(struct tcf_ipt),
};

static __net_init int xt_init_net(struct net *net)
{
	struct tc_action_net *tn = net_generic(net, act_xt_ops.net_id);

	return tc_action_net_init(net, tn, &act_xt_ops);
}

static void __net_exit xt_exit_net(struct list_head *net_list)
{
	tc_action_net_exit(net_list, act_xt_ops.net_id);
}

static struct pernet_operations xt_net_ops = {
	.init = xt_init_net,
	.exit_batch = xt_exit_net,
	.id   = &act_xt_ops.net_id,
	.size = sizeof(struct tc_action_net),
};

MODULE_AUTHOR("Jamal Hadi Salim(2002-13)");
MODULE_DESCRIPTION("Iptables target actions");
MODULE_LICENSE("GPL");
MODULE_ALIAS("act_xt");

static int __init ipt_init_module(void)
{
	int ret1, ret2;

	ret1 = tcf_register_action(&act_xt_ops, &xt_net_ops);
	if (ret1 < 0)
		pr_err("Failed to load xt action\n");

	ret2 = tcf_register_action(&act_ipt_ops, &ipt_net_ops);
	if (ret2 < 0)
		pr_err("Failed to load ipt action\n");

	if (ret1 < 0 && ret2 < 0) {
		return ret1;
	} else
		return 0;
}

static void __exit ipt_cleanup_module(void)
{
	tcf_unregister_action(&act_ipt_ops, &ipt_net_ops);
	tcf_unregister_action(&act_xt_ops, &xt_net_ops);
}

module_init(ipt_init_module);
module_exit(ipt_cleanup_module);
Commit	Line	Data
2874c5fd	1	// SPDX-License-Identifier: GPL-2.0-or-later
1da177e4	2	/*
0c6965dd	3	* net/sched/act_ipt.c iptables target interface
1da177e4 LT	4	*
	5	*TODO: Add other tables. For now we only support the ipv4 table targets
	6	*
0dcffd09	7	* Copyright: Jamal Hadi Salim (2002-13)
1da177e4 LT	8	*/
1da177e4 LT	9
1da177e4 LT	10	#include <linux/types.h>
1da177e4 LT	11	#include <linux/kernel.h>
1da177e4	12	#include <linux/string.h>
1da177e4	13	#include <linux/errno.h>
1da177e4 LT	14	#include <linux/skbuff.h>
	15	#include <linux/rtnetlink.h>
	16	#include <linux/module.h>
	17	#include <linux/init.h>
5a0e3ad6	18	#include <linux/slab.h>
dc5fc579	19	#include <net/netlink.h>
1da177e4 LT	20	#include <net/pkt_sched.h>
	21	#include <linux/tc_act/tc_ipt.h>
	22	#include <net/tc_act/tc_ipt.h>
871cf386	23	#include <net/tc_wrapper.h>
93d75d47	24	#include <net/ip.h>
1da177e4 LT	25
	26	#include <linux/netfilter_ipv4/ip_tables.h>
	27
1da177e4	28
a85a970a	29	static struct tc_action_ops act_ipt_ops;
a85a970a	30	static struct tc_action_ops act_xt_ops;
ddf97ccd	31
ec0acb09 XL	32	static int ipt_init_target(struct net net, struct xt_entry_target t,
ec0acb09 XL	33	char *table, unsigned int hook)
1da177e4	34	{
af5d6dc2	35	struct xt_tgchk_param par;
e60a13e0	36	struct xt_target *target;
4f8a881a	37	struct ipt_entry e = {};
1da177e4 LT	38	int ret = 0;
1da177e4 LT	39
239a87c8 PM	40	target = xt_request_find_target(AF_INET, t->u.user.name,
239a87c8 PM	41	t->u.user.revision);
d2a7b6ba JE	42	if (IS_ERR(target))
d2a7b6ba JE	43	return PTR_ERR(target);
1da177e4	44
1da177e4	45	t->u.kernel.target = target;
96d97030	46	memset(&par, 0, sizeof(par));
ec0acb09	47	par.net = net;
af5d6dc2	48	par.table = table;
4f8a881a	49	par.entryinfo = &e;
af5d6dc2 JE	50	par.target = target;
af5d6dc2 JE	51	par.targinfo = t->data;
b4ee9338	52	par.hook_mask = 1 << hook;
916a917d	53	par.family = NFPROTO_IPV4;
1da177e4	54
916a917d	55	ret = xt_check_target(&par, t->u.target_size - sizeof(*t), 0, false);
367c6790	56	if (ret < 0) {
239a87c8	57	module_put(t->u.kernel.target->me);
18118cdb	58	return ret;
239a87c8	59	}
367c6790	60	return 0;
1da177e4 LT	61	}
1da177e4 LT	62
981471bd	63	static void ipt_destroy_target(struct xt_entry_target t, struct net net)
1da177e4	64	{
a2df1648 JE	65	struct xt_tgdtor_param par = {
	66	.target = t->u.kernel.target,
	67	.targinfo = t->data,
44ef548f	68	.family = NFPROTO_IPV4,
981471bd	69	.net = net,
a2df1648 JE	70	};
	71	if (par.target->destroy != NULL)
	72	par.target->destroy(&par);
	73	module_put(par.target->me);
1da177e4 LT	74	}
1da177e4 LT	75
9a63b255	76	static void tcf_ipt_release(struct tc_action *a)
1da177e4	77	{
86062033	78	struct tcf_ipt *ipt = to_ipt(a);
1e46ef17 DC	79
1e46ef17 DC	80	if (ipt->tcfi_t) {
981471bd	81	ipt_destroy_target(ipt->tcfi_t, a->idrinfo->net);
1e46ef17 DC	82	kfree(ipt->tcfi_t);
1e46ef17 DC	83	}
a5b5c958	84	kfree(ipt->tcfi_tname);
1da177e4 LT	85	}
1da177e4 LT	86
53b2bf3f PM	87	static const struct nla_policy ipt_policy[TCA_IPT_MAX + 1] = {
53b2bf3f PM	88	[TCA_IPT_TABLE] = { .type = NLA_STRING, .len = IFNAMSIZ },
b4ee9338 FW	89	[TCA_IPT_HOOK] = NLA_POLICY_RANGE(NLA_U32, NF_INET_PRE_ROUTING,
b4ee9338 FW	90	NF_INET_NUMHOOKS),
53b2bf3f	91	[TCA_IPT_INDEX] = { .type = NLA_U32 },
87a2e70d	92	[TCA_IPT_TARG] = { .len = sizeof(struct xt_entry_target) },
53b2bf3f PM	93	};
53b2bf3f PM	94
ec0acb09	95	static int __tcf_ipt_init(struct net net, unsigned int id, struct nlattr nla,
a85a970a	96	struct nlattr est, struct tc_action *a,
695176bf	97	const struct tc_action_ops *ops,
abbb0d33	98	struct tcf_proto *tp, u32 flags)
1da177e4	99	{
ec0acb09	100	struct tc_action_net *tn = net_generic(net, id);
695176bf	101	bool bind = flags & TCA_ACT_FLAGS_BIND;
7ba699c6	102	struct nlattr *tb[TCA_IPT_MAX + 1];
e9ce1cd3	103	struct tcf_ipt *ipt;
87a2e70d	104	struct xt_entry_target td, t;
1da177e4	105	char *tname;
b2313077 WC	106	bool exists = false;
b2313077 WC	107	int ret = 0, err;
1da177e4 LT	108	u32 hook = 0;
	109	u32 index = 0;
	110
cee63723	111	if (nla == NULL)
1da177e4 LT	112	return -EINVAL;
1da177e4 LT	113
8cb08174 JB	114	err = nla_parse_nested_deprecated(tb, TCA_IPT_MAX, nla, ipt_policy,
8cb08174 JB	115	NULL);
cee63723 PM	116	if (err < 0)
	117	return err;
	118
a57f19d3 JHS	119	if (tb[TCA_IPT_INDEX] != NULL)
	120	index = nla_get_u32(tb[TCA_IPT_INDEX]);
	121
0190c1d4 VB	122	err = tcf_idr_check_alloc(tn, &index, a, bind);
	123	if (err < 0)
	124	return err;
	125	exists = err;
a57f19d3 JHS	126	if (exists && bind)
	127	return 0;
	128
	129	if (tb[TCA_IPT_HOOK] == NULL \|\| tb[TCA_IPT_TARG] == NULL) {
	130	if (exists)
65a206c0	131	tcf_idr_release(*a, bind);
0190c1d4 VB	132	else
0190c1d4 VB	133	tcf_idr_cleanup(tn, index);
1da177e4	134	return -EINVAL;
a57f19d3	135	}
53b2bf3f	136
87a2e70d	137	td = (struct xt_entry_target *)nla_data(tb[TCA_IPT_TARG]);
aeadd93f	138	if (nla_len(tb[TCA_IPT_TARG]) != td->u.target_size) {
d15eccea	139	if (exists)
65a206c0	140	tcf_idr_release(*a, bind);
0190c1d4 VB	141	else
0190c1d4 VB	142	tcf_idr_cleanup(tn, index);
1da177e4	143	return -EINVAL;
d15eccea	144	}
1da177e4	145
d15eccea	146	if (!exists) {
65a206c0	147	ret = tcf_idr_create(tn, index, est, a, ops, bind,
40bd094d	148	false, flags);
0190c1d4 VB	149	if (ret) {
0190c1d4 VB	150	tcf_idr_cleanup(tn, index);
86062033	151	return ret;
0190c1d4	152	}
1da177e4 LT	153	ret = ACT_P_CREATED;
1da177e4 LT	154	} else {
1a29321e JHS	155	if (bind)/* dont override defaults */
1a29321e JHS	156	return 0;
1a29321e	157
695176bf	158	if (!(flags & TCA_ACT_FLAGS_REPLACE)) {
4e8ddd7f	159	tcf_idr_release(*a, bind);
1da177e4	160	return -EEXIST;
4e8ddd7f	161	}
1da177e4	162	}
b4ee9338 FW	163
b4ee9338 FW	164	err = -EINVAL;
1587bac4	165	hook = nla_get_u32(tb[TCA_IPT_HOOK]);
b4ee9338 FW	166	switch (hook) {
	167	case NF_INET_PRE_ROUTING:
	168	break;
	169	case NF_INET_POST_ROUTING:
	170	break;
	171	default:
	172	goto err1;
	173	}
	174
	175	if (tb[TCA_IPT_TABLE]) {
	176	/* mangle only for now */
	177	if (nla_strcmp(tb[TCA_IPT_TABLE], "mangle"))
	178	goto err1;
	179	}
1da177e4	180
b4ee9338	181	tname = kstrdup("mangle", GFP_KERNEL);
e9ce1cd3	182	if (unlikely(!tname))
1da177e4	183	goto err1;
1da177e4	184
c7b1b249	185	t = kmemdup(td, td->u.target_size, GFP_KERNEL);
e9ce1cd3	186	if (unlikely(!t))
1da177e4	187	goto err2;
1da177e4	188
ec0acb09	189	err = ipt_init_target(net, t, tname, hook);
cc7ec456	190	if (err < 0)
1da177e4 LT	191	goto err3;
1da177e4 LT	192
a85a970a WC	193	ipt = to_ipt(*a);
a85a970a WC	194
e9ce1cd3	195	spin_lock_bh(&ipt->tcf_lock);
1da177e4	196	if (ret != ACT_P_CREATED) {
981471bd	197	ipt_destroy_target(ipt->tcfi_t, net);
e9ce1cd3 DM	198	kfree(ipt->tcfi_tname);
e9ce1cd3 DM	199	kfree(ipt->tcfi_t);
1da177e4	200	}
e9ce1cd3 DM	201	ipt->tcfi_tname = tname;
	202	ipt->tcfi_t = t;
	203	ipt->tcfi_hook = hook;
	204	spin_unlock_bh(&ipt->tcf_lock);
1da177e4 LT	205	return ret;
	206
	207	err3:
	208	kfree(t);
	209	err2:
	210	kfree(tname);
	211	err1:
8f67c90e	212	tcf_idr_release(*a, bind);
1da177e4 LT	213	return err;
	214	}
	215
ddf97ccd	216	static int tcf_ipt_init(struct net net, struct nlattr nla,
695176bf CW	217	struct nlattr est, struct tc_action *a,
695176bf CW	218	struct tcf_proto *tp,
abbb0d33	219	u32 flags, struct netlink_ext_ack *extack)
ddf97ccd	220	{
acd0a7ab ZS	221	return __tcf_ipt_init(net, act_ipt_ops.net_id, nla, est,
acd0a7ab ZS	222	a, &act_ipt_ops, tp, flags);
ddf97ccd WC	223	}
	224
	225	static int tcf_xt_init(struct net net, struct nlattr nla,
695176bf CW	226	struct nlattr est, struct tc_action *a,
695176bf CW	227	struct tcf_proto *tp,
abbb0d33	228	u32 flags, struct netlink_ext_ack *extack)
ddf97ccd	229	{
acd0a7ab ZS	230	return __tcf_ipt_init(net, act_xt_ops.net_id, nla, est,
acd0a7ab ZS	231	a, &act_xt_ops, tp, flags);
ddf97ccd WC	232	}
ddf97ccd WC	233
b2dc32dc FW	234	static bool tcf_ipt_act_check(struct sk_buff *skb)
	235	{
	236	const struct iphdr *iph;
	237	unsigned int nhoff, len;
	238
	239	if (!pskb_may_pull(skb, sizeof(struct iphdr)))
	240	return false;
	241
	242	nhoff = skb_network_offset(skb);
	243	iph = ip_hdr(skb);
	244	if (iph->ihl < 5 \|\| iph->version != 4)
	245	return false;
	246
	247	len = skb_ip_totlen(skb);
	248	if (skb->len < nhoff + len \|\| len < (iph->ihl * 4u))
	249	return false;
	250
	251	return pskb_may_pull(skb, iph->ihl * 4u);
	252	}
	253
871cf386 PT	254	TC_INDIRECT_SCOPE int tcf_ipt_act(struct sk_buff *skb,
	255	const struct tc_action *a,
	256	struct tcf_result *res)
1da177e4	257	{
93d75d47	258	char saved_cb[sizeof_field(struct sk_buff, cb)];
1da177e4	259	int ret = 0, result = 0;
a85a970a	260	struct tcf_ipt *ipt = to_ipt(a);
4b560b44	261	struct xt_action_param par;
613dbd95 PNA	262	struct nf_hook_state state = {
	263	.net = dev_net(skb->dev),
	264	.in = skb->dev,
	265	.hook = ipt->tcfi_hook,
	266	.pf = NFPROTO_IPV4,
	267	};
1da177e4	268
b2dc32dc FW	269	if (skb_protocol(skb, false) != htons(ETH_P_IP))
	270	return TC_ACT_UNSPEC;
	271
14bbd6a5 PS	272	if (skb_unclone(skb, GFP_ATOMIC))
14bbd6a5 PS	273	return TC_ACT_UNSPEC;
1da177e4	274
b2dc32dc FW	275	if (!tcf_ipt_act_check(skb))
	276	return TC_ACT_UNSPEC;
	277
	278	if (state.hook == NF_INET_POST_ROUTING) {
	279	if (!skb_dst(skb))
	280	return TC_ACT_UNSPEC;
	281
	282	state.out = skb->dev;
	283	}
	284
93d75d47 FW	285	memcpy(saved_cb, skb->cb, sizeof(saved_cb));
93d75d47 FW	286
e9ce1cd3	287	spin_lock(&ipt->tcf_lock);
1da177e4	288
9c4a4e48	289	tcf_lastuse_update(&ipt->tcf_tm);
bfe0d029	290	bstats_update(&ipt->tcf_bstats, skb);
1da177e4 LT	291
1da177e4 LT	292	/* yes, we have to worry about both in and out dev
cc7ec456 ED	293	* worry later - danger - this API seems to have changed
	294	* from earlier kernels
	295	*/
613dbd95	296	par.state = &state;
7eb35586 JE	297	par.target = ipt->tcfi_t->u.kernel.target;
7eb35586 JE	298	par.targinfo = ipt->tcfi_t->data;
93d75d47 FW	299
	300	memset(IPCB(skb), 0, sizeof(struct inet_skb_parm));
	301
7eb35586 JE	302	ret = par.target->target(skb, &par);
7eb35586 JE	303
1da177e4 LT	304	switch (ret) {
	305	case NF_ACCEPT:
	306	result = TC_ACT_OK;
	307	break;
	308	case NF_DROP:
	309	result = TC_ACT_SHOT;
e9ce1cd3	310	ipt->tcf_qstats.drops++;
1da177e4	311	break;
243bf6e2	312	case XT_CONTINUE:
1da177e4 LT	313	result = TC_ACT_PIPE;
	314	break;
	315	default:
e87cc472 JP	316	net_notice_ratelimited("tc filter: Bogus netfilter code %d assume ACCEPT\n",
e87cc472 JP	317	ret);
95df1b16	318	result = TC_ACT_OK;
1da177e4 LT	319	break;
1da177e4 LT	320	}
e9ce1cd3	321	spin_unlock(&ipt->tcf_lock);
93d75d47 FW	322
	323	memcpy(skb->cb, saved_cb, sizeof(skb->cb));
	324
1da177e4 LT	325	return result;
	326
	327	}
	328
0b0f43fe JHS	329	static int tcf_ipt_dump(struct sk_buff skb, struct tc_action a, int bind,
0b0f43fe JHS	330	int ref)
1da177e4	331	{
27a884dc	332	unsigned char *b = skb_tail_pointer(skb);
a85a970a	333	struct tcf_ipt *ipt = to_ipt(a);
87a2e70d	334	struct xt_entry_target *t;
1da177e4 LT	335	struct tcf_t tm;
1da177e4 LT	336	struct tc_cnt c;
1da177e4 LT	337
1da177e4 LT	338	/* for simple targets kernel size == user size
cc7ec456 ED	339	* user name = target name
	340	* for foolproof you need to not assume this
	341	*/
1da177e4	342
ff25276d	343	spin_lock_bh(&ipt->tcf_lock);
c7b1b249	344	t = kmemdup(ipt->tcfi_t, ipt->tcfi_t->u.user.target_size, GFP_ATOMIC);
e9ce1cd3	345	if (unlikely(!t))
7ba699c6	346	goto nla_put_failure;
1da177e4	347
036bb443 VB	348	c.bindcnt = atomic_read(&ipt->tcf_bindcnt) - bind;
036bb443 VB	349	c.refcnt = refcount_read(&ipt->tcf_refcnt) - ref;
e9ce1cd3 DM	350	strcpy(t->u.user.name, ipt->tcfi_t->u.kernel.target->name);
e9ce1cd3 DM	351
1b34ec43 DM	352	if (nla_put(skb, TCA_IPT_TARG, ipt->tcfi_t->u.user.target_size, t) \|\|
	353	nla_put_u32(skb, TCA_IPT_INDEX, ipt->tcf_index) \|\|
	354	nla_put_u32(skb, TCA_IPT_HOOK, ipt->tcfi_hook) \|\|
	355	nla_put(skb, TCA_IPT_CNT, sizeof(struct tc_cnt), &c) \|\|
	356	nla_put_string(skb, TCA_IPT_TABLE, ipt->tcfi_tname))
	357	goto nla_put_failure;
48d8ee16 JHS	358
48d8ee16 JHS	359	tcf_tm_dump(&tm, &ipt->tcf_tm);
9854518e	360	if (nla_put_64bit(skb, TCA_IPT_TM, sizeof(tm), &tm, TCA_IPT_PAD))
1b34ec43	361	goto nla_put_failure;
48d8ee16	362
ff25276d	363	spin_unlock_bh(&ipt->tcf_lock);
1da177e4 LT	364	kfree(t);
	365	return skb->len;
	366
7ba699c6	367	nla_put_failure:
ff25276d	368	spin_unlock_bh(&ipt->tcf_lock);
dc5fc579	369	nlmsg_trim(skb, b);
1da177e4 LT	370	kfree(t);
	371	return -1;
	372	}
	373
	374	static struct tc_action_ops act_ipt_ops = {
	375	.kind = "ipt",
eddd2cf1	376	.id = TCA_ID_IPT,
1da177e4	377	.owner = THIS_MODULE,
11b9695b	378	.act = tcf_ipt_act,
1da177e4	379	.dump = tcf_ipt_dump,
86062033	380	.cleanup = tcf_ipt_release,
1da177e4	381	.init = tcf_ipt_init,
a85a970a	382	.size = sizeof(struct tcf_ipt),
ddf97ccd WC	383	};
	384
	385	static __net_init int ipt_init_net(struct net *net)
	386	{
acd0a7ab	387	struct tc_action_net *tn = net_generic(net, act_ipt_ops.net_id);
ddf97ccd	388
981471bd	389	return tc_action_net_init(net, tn, &act_ipt_ops);
ddf97ccd WC	390	}
ddf97ccd WC	391
039af9c6	392	static void __net_exit ipt_exit_net(struct list_head *net_list)
ddf97ccd	393	{
acd0a7ab	394	tc_action_net_exit(net_list, act_ipt_ops.net_id);
ddf97ccd WC	395	}
	396
	397	static struct pernet_operations ipt_net_ops = {
	398	.init = ipt_init_net,
039af9c6	399	.exit_batch = ipt_exit_net,
acd0a7ab	400	.id = &act_ipt_ops.net_id,
ddf97ccd	401	.size = sizeof(struct tc_action_net),
1da177e4 LT	402	};
1da177e4 LT	403
0dcffd09 JHS	404	static struct tc_action_ops act_xt_ops = {
0dcffd09 JHS	405	.kind = "xt",
eddd2cf1	406	.id = TCA_ID_XT,
0dcffd09	407	.owner = THIS_MODULE,
11b9695b	408	.act = tcf_ipt_act,
0dcffd09	409	.dump = tcf_ipt_dump,
86062033	410	.cleanup = tcf_ipt_release,
ddf97ccd	411	.init = tcf_xt_init,
a85a970a	412	.size = sizeof(struct tcf_ipt),
ddf97ccd WC	413	};
	414
	415	static __net_init int xt_init_net(struct net *net)
	416	{
acd0a7ab	417	struct tc_action_net *tn = net_generic(net, act_xt_ops.net_id);
ddf97ccd	418
981471bd	419	return tc_action_net_init(net, tn, &act_xt_ops);
ddf97ccd WC	420	}
ddf97ccd WC	421
039af9c6	422	static void __net_exit xt_exit_net(struct list_head *net_list)
ddf97ccd	423	{
acd0a7ab	424	tc_action_net_exit(net_list, act_xt_ops.net_id);
ddf97ccd WC	425	}
	426
	427	static struct pernet_operations xt_net_ops = {
	428	.init = xt_init_net,
039af9c6	429	.exit_batch = xt_exit_net,
acd0a7ab	430	.id = &act_xt_ops.net_id,
ddf97ccd	431	.size = sizeof(struct tc_action_net),
0dcffd09 JHS	432	};
	433
	434	MODULE_AUTHOR("Jamal Hadi Salim(2002-13)");
1da177e4 LT	435	MODULE_DESCRIPTION("Iptables target actions");
1da177e4 LT	436	MODULE_LICENSE("GPL");
0dcffd09	437	MODULE_ALIAS("act_xt");
1da177e4	438
e9ce1cd3	439	static int __init ipt_init_module(void)
1da177e4	440	{
4f1e9d89	441	int ret1, ret2;
369ba567	442
ddf97ccd	443	ret1 = tcf_register_action(&act_xt_ops, &xt_net_ops);
0dcffd09	444	if (ret1 < 0)
ddf97ccd WC	445	pr_err("Failed to load xt action\n");
	446
	447	ret2 = tcf_register_action(&act_ipt_ops, &ipt_net_ops);
0dcffd09	448	if (ret2 < 0)
ddf97ccd	449	pr_err("Failed to load ipt action\n");
0dcffd09	450
369ba567	451	if (ret1 < 0 && ret2 < 0) {
0dcffd09	452	return ret1;
369ba567	453	} else
0dcffd09	454	return 0;
1da177e4 LT	455	}
1da177e4 LT	456
e9ce1cd3	457	static void __exit ipt_cleanup_module(void)
1da177e4	458	{
ddf97ccd WC	459	tcf_unregister_action(&act_ipt_ops, &ipt_net_ops);
ddf97ccd WC	460	tcf_unregister_action(&act_xt_ops, &xt_net_ops);
1da177e4 LT	461	}
	462
	463	module_init(ipt_init_module);
	464	module_exit(ipt_cleanup_module);