[mirror_ubuntu-artful-kernel.git] / net / netfilter / xt_TPROXY.c

/*
 * Transparent proxy support for Linux/iptables
 *
 * Copyright (c) 2006-2010 BalaBit IT Ltd.
 * Author: Balazs Scheidler, Krisztian Kovacs
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 */
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/module.h>
#include <linux/skbuff.h>
#include <linux/ip.h>
#include <net/checksum.h>
#include <net/udp.h>
#include <net/tcp.h>
#include <net/inet_sock.h>
#include <net/inet_hashtables.h>
#include <linux/inetdevice.h>
#include <linux/netfilter/x_tables.h>
#include <linux/netfilter_ipv4/ip_tables.h>

#include <net/netfilter/ipv4/nf_defrag_ipv4.h>

#if IS_ENABLED(CONFIG_IP6_NF_IPTABLES)
#define XT_TPROXY_HAVE_IPV6 1
#include <net/if_inet6.h>
#include <net/addrconf.h>
#include <net/inet6_hashtables.h>
#include <linux/netfilter_ipv6/ip6_tables.h>
#include <net/netfilter/ipv6/nf_defrag_ipv6.h>
#endif

#include <linux/netfilter/xt_TPROXY.h>

enum nf_tproxy_lookup_t {
	 NFT_LOOKUP_LISTENER,
	 NFT_LOOKUP_ESTABLISHED,
};

static bool tproxy_sk_is_transparent(struct sock *sk)
{
	switch (sk->sk_state) {
	case TCP_TIME_WAIT:
		if (inet_twsk(sk)->tw_transparent)
			return true;
		break;
	case TCP_NEW_SYN_RECV:
		if (inet_rsk(inet_reqsk(sk))->no_srccheck)
			return true;
		break;
	default:
		if (inet_sk(sk)->transparent)
			return true;
	}

	sock_gen_put(sk);
	return false;
}

static inline __be32
tproxy_laddr4(struct sk_buff *skb, __be32 user_laddr, __be32 daddr)
{
	struct in_device *indev;
	__be32 laddr;

	if (user_laddr)
		return user_laddr;

	laddr = 0;
	rcu_read_lock();
	indev = __in_dev_get_rcu(skb->dev);
	for_primary_ifa(indev) {
		laddr = ifa->ifa_local;
		break;
	} endfor_ifa(indev);
	rcu_read_unlock();

	return laddr ? laddr : daddr;
}

/*
 * This is used when the user wants to intercept a connection matching
 * an explicit iptables rule. In this case the sockets are assumed
 * matching in preference order:
 *
 *   - match: if there's a fully established connection matching the
 *     _packet_ tuple, it is returned, assuming the redirection
 *     already took place and we process a packet belonging to an
 *     established connection
 *
 *   - match: if there's a listening socket matching the redirection
 *     (e.g. on-port & on-ip of the connection), it is returned,
 *     regardless if it was bound to 0.0.0.0 or an explicit
 *     address. The reasoning is that if there's an explicit rule, it
 *     does not really matter if the listener is bound to an interface
 *     or to 0. The user already stated that he wants redirection
 *     (since he added the rule).
 *
 * Please note that there's an overlap between what a TPROXY target
 * and a socket match will match. Normally if you have both rules the
 * "socket" match will be the first one, effectively all packets
 * belonging to established connections going through that one.
 */
static inline struct sock *
nf_tproxy_get_sock_v4(struct net *net, struct sk_buff *skb, void *hp,
		      const u8 protocol,
		      const __be32 saddr, const __be32 daddr,
		      const __be16 sport, const __be16 dport,
		      const struct net_device *in,
		      const enum nf_tproxy_lookup_t lookup_type)
{
	struct sock *sk;
	struct tcphdr *tcph;

	switch (protocol) {
	case IPPROTO_TCP:
		switch (lookup_type) {
		case NFT_LOOKUP_LISTENER:
			tcph = hp;
			sk = inet_lookup_listener(net, &tcp_hashinfo, skb,
						    ip_hdrlen(skb) +
						      __tcp_hdrlen(tcph),
						    saddr, sport,
						    daddr, dport,
						    in->ifindex);

			if (sk && !refcount_inc_not_zero(&sk->sk_refcnt))
				sk = NULL;
			/* NOTE: we return listeners even if bound to
			 * 0.0.0.0, those are filtered out in
			 * xt_socket, since xt_TPROXY needs 0 bound
			 * listeners too
			 */
			break;
		case NFT_LOOKUP_ESTABLISHED:
			sk = inet_lookup_established(net, &tcp_hashinfo,
						    saddr, sport, daddr, dport,
						    in->ifindex);
			break;
		default:
			BUG();
		}
		break;
	case IPPROTO_UDP:
		sk = udp4_lib_lookup(net, saddr, sport, daddr, dport,
				     in->ifindex);
		if (sk) {
			int connected = (sk->sk_state == TCP_ESTABLISHED);
			int wildcard = (inet_sk(sk)->inet_rcv_saddr == 0);

			/* NOTE: we return listeners even if bound to
			 * 0.0.0.0, those are filtered out in
			 * xt_socket, since xt_TPROXY needs 0 bound
			 * listeners too
			 */
			if ((lookup_type == NFT_LOOKUP_ESTABLISHED && (!connected || wildcard)) ||
			    (lookup_type == NFT_LOOKUP_LISTENER && connected)) {
				sock_put(sk);
				sk = NULL;
			}
		}
		break;
	default:
		WARN_ON(1);
		sk = NULL;
	}

	pr_debug("tproxy socket lookup: proto %u %08x:%u -> %08x:%u, lookup type: %d, sock %p\n",
		 protocol, ntohl(saddr), ntohs(sport), ntohl(daddr), ntohs(dport), lookup_type, sk);

	return sk;
}

#ifdef XT_TPROXY_HAVE_IPV6
static inline struct sock *
nf_tproxy_get_sock_v6(struct net *net, struct sk_buff *skb, int thoff, void *hp,
		      const u8 protocol,
		      const struct in6_addr *saddr, const struct in6_addr *daddr,
		      const __be16 sport, const __be16 dport,
		      const struct net_device *in,
		      const enum nf_tproxy_lookup_t lookup_type)
{
	struct sock *sk;
	struct tcphdr *tcph;

	switch (protocol) {
	case IPPROTO_TCP:
		switch (lookup_type) {
		case NFT_LOOKUP_LISTENER:
			tcph = hp;
			sk = inet6_lookup_listener(net, &tcp_hashinfo, skb,
						   thoff + __tcp_hdrlen(tcph),
						   saddr, sport,
						   daddr, ntohs(dport),
						   in->ifindex);

			if (sk && !refcount_inc_not_zero(&sk->sk_refcnt))
				sk = NULL;
			/* NOTE: we return listeners even if bound to
			 * 0.0.0.0, those are filtered out in
			 * xt_socket, since xt_TPROXY needs 0 bound
			 * listeners too
			 */
			break;
		case NFT_LOOKUP_ESTABLISHED:
			sk = __inet6_lookup_established(net, &tcp_hashinfo,
							saddr, sport, daddr, ntohs(dport),
							in->ifindex);
			break;
		default:
			BUG();
		}
		break;
	case IPPROTO_UDP:
		sk = udp6_lib_lookup(net, saddr, sport, daddr, dport,
				     in->ifindex);
		if (sk) {
			int connected = (sk->sk_state == TCP_ESTABLISHED);
			int wildcard = ipv6_addr_any(&sk->sk_v6_rcv_saddr);

			/* NOTE: we return listeners even if bound to
			 * 0.0.0.0, those are filtered out in
			 * xt_socket, since xt_TPROXY needs 0 bound
			 * listeners too
			 */
			if ((lookup_type == NFT_LOOKUP_ESTABLISHED && (!connected || wildcard)) ||
			    (lookup_type == NFT_LOOKUP_LISTENER && connected)) {
				sock_put(sk);
				sk = NULL;
			}
		}
		break;
	default:
		WARN_ON(1);
		sk = NULL;
	}

	pr_debug("tproxy socket lookup: proto %u %pI6:%u -> %pI6:%u, lookup type: %d, sock %p\n",
		 protocol, saddr, ntohs(sport), daddr, ntohs(dport), lookup_type, sk);

	return sk;
}
#endif

/**
 * tproxy_handle_time_wait4 - handle IPv4 TCP TIME_WAIT reopen redirections
 * @skb:	The skb being processed.
 * @laddr:	IPv4 address to redirect to or zero.
 * @lport:	TCP port to redirect to or zero.
 * @sk:		The TIME_WAIT TCP socket found by the lookup.
 *
 * We have to handle SYN packets arriving to TIME_WAIT sockets
 * differently: instead of reopening the connection we should rather
 * redirect the new connection to the proxy if there's a listener
 * socket present.
 *
 * tproxy_handle_time_wait4() consumes the socket reference passed in.
 *
 * Returns the listener socket if there's one, the TIME_WAIT socket if
 * no such listener is found, or NULL if the TCP header is incomplete.
 */
static struct sock *
tproxy_handle_time_wait4(struct net *net, struct sk_buff *skb,
			 __be32 laddr, __be16 lport, struct sock *sk)
{
	const struct iphdr *iph = ip_hdr(skb);
	struct tcphdr _hdr, *hp;

	hp = skb_header_pointer(skb, ip_hdrlen(skb), sizeof(_hdr), &_hdr);
	if (hp == NULL) {
		inet_twsk_put(inet_twsk(sk));
		return NULL;
	}

	if (hp->syn && !hp->rst && !hp->ack && !hp->fin) {
		/* SYN to a TIME_WAIT socket, we'd rather redirect it
		 * to a listener socket if there's one */
		struct sock *sk2;

		sk2 = nf_tproxy_get_sock_v4(net, skb, hp, iph->protocol,
					    iph->saddr, laddr ? laddr : iph->daddr,
					    hp->source, lport ? lport : hp->dest,
					    skb->dev, NFT_LOOKUP_LISTENER);
		if (sk2) {
			inet_twsk_deschedule_put(inet_twsk(sk));
			sk = sk2;
		}
	}

	return sk;
}

/* assign a socket to the skb -- consumes sk */
static void
nf_tproxy_assign_sock(struct sk_buff *skb, struct sock *sk)
{
	skb_orphan(skb);
	skb->sk = sk;
	skb->destructor = sock_edemux;
}

static unsigned int
tproxy_tg4(struct net *net, struct sk_buff *skb, __be32 laddr, __be16 lport,
	   u_int32_t mark_mask, u_int32_t mark_value)
{
	const struct iphdr *iph = ip_hdr(skb);
	struct udphdr _hdr, *hp;
	struct sock *sk;

	hp = skb_header_pointer(skb, ip_hdrlen(skb), sizeof(_hdr), &_hdr);
	if (hp == NULL)
		return NF_DROP;

	/* check if there's an ongoing connection on the packet
	 * addresses, this happens if the redirect already happened
	 * and the current packet belongs to an already established
	 * connection */
	sk = nf_tproxy_get_sock_v4(net, skb, hp, iph->protocol,
				   iph->saddr, iph->daddr,
				   hp->source, hp->dest,
				   skb->dev, NFT_LOOKUP_ESTABLISHED);

	laddr = tproxy_laddr4(skb, laddr, iph->daddr);
	if (!lport)
		lport = hp->dest;

	/* UDP has no TCP_TIME_WAIT state, so we never enter here */
	if (sk && sk->sk_state == TCP_TIME_WAIT)
		/* reopening a TIME_WAIT connection needs special handling */
		sk = tproxy_handle_time_wait4(net, skb, laddr, lport, sk);
	else if (!sk)
		/* no, there's no established connection, check if
		 * there's a listener on the redirected addr/port */
		sk = nf_tproxy_get_sock_v4(net, skb, hp, iph->protocol,
					   iph->saddr, laddr,
					   hp->source, lport,
					   skb->dev, NFT_LOOKUP_LISTENER);

	/* NOTE: assign_sock consumes our sk reference */
	if (sk && tproxy_sk_is_transparent(sk)) {
		/* This should be in a separate target, but we don't do multiple
		   targets on the same rule yet */
		skb->mark = (skb->mark & ~mark_mask) ^ mark_value;

		pr_debug("redirecting: proto %hhu %pI4:%hu -> %pI4:%hu, mark: %x\n",
			 iph->protocol, &iph->daddr, ntohs(hp->dest),
			 &laddr, ntohs(lport), skb->mark);

		nf_tproxy_assign_sock(skb, sk);
		return NF_ACCEPT;
	}

	pr_debug("no socket, dropping: proto %hhu %pI4:%hu -> %pI4:%hu, mark: %x\n",
		 iph->protocol, &iph->saddr, ntohs(hp->source),
		 &iph->daddr, ntohs(hp->dest), skb->mark);
	return NF_DROP;
}

static unsigned int
tproxy_tg4_v0(struct sk_buff *skb, const struct xt_action_param *par)
{
	const struct xt_tproxy_target_info *tgi = par->targinfo;

	return tproxy_tg4(xt_net(par), skb, tgi->laddr, tgi->lport,
			  tgi->mark_mask, tgi->mark_value);
}

static unsigned int
tproxy_tg4_v1(struct sk_buff *skb, const struct xt_action_param *par)
{
	const struct xt_tproxy_target_info_v1 *tgi = par->targinfo;

	return tproxy_tg4(xt_net(par), skb, tgi->laddr.ip, tgi->lport,
			  tgi->mark_mask, tgi->mark_value);
}

#ifdef XT_TPROXY_HAVE_IPV6

static inline const struct in6_addr *
tproxy_laddr6(struct sk_buff *skb, const struct in6_addr *user_laddr,
	      const struct in6_addr *daddr)
{
	struct inet6_dev *indev;
	struct inet6_ifaddr *ifa;
	struct in6_addr *laddr;

	if (!ipv6_addr_any(user_laddr))
		return user_laddr;
	laddr = NULL;

	rcu_read_lock();
	indev = __in6_dev_get(skb->dev);
	if (indev) {
		read_lock_bh(&indev->lock);
		list_for_each_entry(ifa, &indev->addr_list, if_list) {
			if (ifa->flags & (IFA_F_TENTATIVE | IFA_F_DEPRECATED))
				continue;

			laddr = &ifa->addr;
			break;
		}
		read_unlock_bh(&indev->lock);
	}
	rcu_read_unlock();

	return laddr ? laddr : daddr;
}

/**
 * tproxy_handle_time_wait6 - handle IPv6 TCP TIME_WAIT reopen redirections
 * @skb:	The skb being processed.
 * @tproto:	Transport protocol.
 * @thoff:	Transport protocol header offset.
 * @par:	Iptables target parameters.
 * @sk:		The TIME_WAIT TCP socket found by the lookup.
 *
 * We have to handle SYN packets arriving to TIME_WAIT sockets
 * differently: instead of reopening the connection we should rather
 * redirect the new connection to the proxy if there's a listener
 * socket present.
 *
 * tproxy_handle_time_wait6() consumes the socket reference passed in.
 *
 * Returns the listener socket if there's one, the TIME_WAIT socket if
 * no such listener is found, or NULL if the TCP header is incomplete.
 */
static struct sock *
tproxy_handle_time_wait6(struct sk_buff *skb, int tproto, int thoff,
			 const struct xt_action_param *par,
			 struct sock *sk)
{
	const struct ipv6hdr *iph = ipv6_hdr(skb);
	struct tcphdr _hdr, *hp;
	const struct xt_tproxy_target_info_v1 *tgi = par->targinfo;

	hp = skb_header_pointer(skb, thoff, sizeof(_hdr), &_hdr);
	if (hp == NULL) {
		inet_twsk_put(inet_twsk(sk));
		return NULL;
	}

	if (hp->syn && !hp->rst && !hp->ack && !hp->fin) {
		/* SYN to a TIME_WAIT socket, we'd rather redirect it
		 * to a listener socket if there's one */
		struct sock *sk2;

		sk2 = nf_tproxy_get_sock_v6(xt_net(par), skb, thoff, hp, tproto,
					    &iph->saddr,
					    tproxy_laddr6(skb, &tgi->laddr.in6, &iph->daddr),
					    hp->source,
					    tgi->lport ? tgi->lport : hp->dest,
					    skb->dev, NFT_LOOKUP_LISTENER);
		if (sk2) {
			inet_twsk_deschedule_put(inet_twsk(sk));
			sk = sk2;
		}
	}

	return sk;
}

static unsigned int
tproxy_tg6_v1(struct sk_buff *skb, const struct xt_action_param *par)
{
	const struct ipv6hdr *iph = ipv6_hdr(skb);
	const struct xt_tproxy_target_info_v1 *tgi = par->targinfo;
	struct udphdr _hdr, *hp;
	struct sock *sk;
	const struct in6_addr *laddr;
	__be16 lport;
	int thoff = 0;
	int tproto;

	tproto = ipv6_find_hdr(skb, &thoff, -1, NULL, NULL);
	if (tproto < 0) {
		pr_debug("unable to find transport header in IPv6 packet, dropping\n");
		return NF_DROP;
	}

	hp = skb_header_pointer(skb, thoff, sizeof(_hdr), &_hdr);
	if (hp == NULL) {
		pr_debug("unable to grab transport header contents in IPv6 packet, dropping\n");
		return NF_DROP;
	}

	/* check if there's an ongoing connection on the packet
	 * addresses, this happens if the redirect already happened
	 * and the current packet belongs to an already established
	 * connection */
	sk = nf_tproxy_get_sock_v6(xt_net(par), skb, thoff, hp, tproto,
				   &iph->saddr, &iph->daddr,
				   hp->source, hp->dest,
				   xt_in(par), NFT_LOOKUP_ESTABLISHED);

	laddr = tproxy_laddr6(skb, &tgi->laddr.in6, &iph->daddr);
	lport = tgi->lport ? tgi->lport : hp->dest;

	/* UDP has no TCP_TIME_WAIT state, so we never enter here */
	if (sk && sk->sk_state == TCP_TIME_WAIT)
		/* reopening a TIME_WAIT connection needs special handling */
		sk = tproxy_handle_time_wait6(skb, tproto, thoff, par, sk);
	else if (!sk)
		/* no there's no established connection, check if
		 * there's a listener on the redirected addr/port */
		sk = nf_tproxy_get_sock_v6(xt_net(par), skb, thoff, hp,
					   tproto, &iph->saddr, laddr,
					   hp->source, lport,
					   xt_in(par), NFT_LOOKUP_LISTENER);

	/* NOTE: assign_sock consumes our sk reference */
	if (sk && tproxy_sk_is_transparent(sk)) {
		/* This should be in a separate target, but we don't do multiple
		   targets on the same rule yet */
		skb->mark = (skb->mark & ~tgi->mark_mask) ^ tgi->mark_value;

		pr_debug("redirecting: proto %hhu %pI6:%hu -> %pI6:%hu, mark: %x\n",
			 tproto, &iph->saddr, ntohs(hp->source),
			 laddr, ntohs(lport), skb->mark);

		nf_tproxy_assign_sock(skb, sk);
		return NF_ACCEPT;
	}

	pr_debug("no socket, dropping: proto %hhu %pI6:%hu -> %pI6:%hu, mark: %x\n",
		 tproto, &iph->saddr, ntohs(hp->source),
		 &iph->daddr, ntohs(hp->dest), skb->mark);

	return NF_DROP;
}

static int tproxy_tg6_check(const struct xt_tgchk_param *par)
{
	const struct ip6t_ip6 *i = par->entryinfo;
	int err;

	err = nf_defrag_ipv6_enable(par->net);
	if (err)
		return err;

	if ((i->proto == IPPROTO_TCP || i->proto == IPPROTO_UDP) &&
	    !(i->invflags & IP6T_INV_PROTO))
		return 0;

	pr_info("Can be used only in combination with "
		"either -p tcp or -p udp\n");
	return -EINVAL;
}
#endif

static int tproxy_tg4_check(const struct xt_tgchk_param *par)
{
	const struct ipt_ip *i = par->entryinfo;
	int err;

	err = nf_defrag_ipv4_enable(par->net);
	if (err)
		return err;

	if ((i->proto == IPPROTO_TCP || i->proto == IPPROTO_UDP)
	    && !(i->invflags & IPT_INV_PROTO))
		return 0;

	pr_info("Can be used only in combination with "
		"either -p tcp or -p udp\n");
	return -EINVAL;
}

static struct xt_target tproxy_tg_reg[] __read_mostly = {
	{
		.name		= "TPROXY",
		.family		= NFPROTO_IPV4,
		.table		= "mangle",
		.target		= tproxy_tg4_v0,
		.revision	= 0,
		.targetsize	= sizeof(struct xt_tproxy_target_info),
		.checkentry	= tproxy_tg4_check,
		.hooks		= 1 << NF_INET_PRE_ROUTING,
		.me		= THIS_MODULE,
	},
	{
		.name		= "TPROXY",
		.family		= NFPROTO_IPV4,
		.table		= "mangle",
		.target		= tproxy_tg4_v1,
		.revision	= 1,
		.targetsize	= sizeof(struct xt_tproxy_target_info_v1),
		.checkentry	= tproxy_tg4_check,
		.hooks		= 1 << NF_INET_PRE_ROUTING,
		.me		= THIS_MODULE,
	},
#ifdef XT_TPROXY_HAVE_IPV6
	{
		.name		= "TPROXY",
		.family		= NFPROTO_IPV6,
		.table		= "mangle",
		.target		= tproxy_tg6_v1,
		.revision	= 1,
		.targetsize	= sizeof(struct xt_tproxy_target_info_v1),
		.checkentry	= tproxy_tg6_check,
		.hooks		= 1 << NF_INET_PRE_ROUTING,
		.me		= THIS_MODULE,
	},
#endif

};

static int __init tproxy_tg_init(void)
{
	return xt_register_targets(tproxy_tg_reg, ARRAY_SIZE(tproxy_tg_reg));
}

static void __exit tproxy_tg_exit(void)
{
	xt_unregister_targets(tproxy_tg_reg, ARRAY_SIZE(tproxy_tg_reg));
}

module_init(tproxy_tg_init);
module_exit(tproxy_tg_exit);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Balazs Scheidler, Krisztian Kovacs");
MODULE_DESCRIPTION("Netfilter transparent proxy (TPROXY) target module.");
MODULE_ALIAS("ipt_TPROXY");
MODULE_ALIAS("ip6t_TPROXY");
Commit	Line	Data
e8439270 KK	1	/*
	2	* Transparent proxy support for Linux/iptables
	3	*
6ad78893	4	* Copyright (c) 2006-2010 BalaBit IT Ltd.
e8439270 KK	5	* Author: Balazs Scheidler, Krisztian Kovacs
	6	*
	7	* This program is free software; you can redistribute it and/or modify
	8	* it under the terms of the GNU General Public License version 2 as
	9	* published by the Free Software Foundation.
	10	*
	11	*/
ff67e4e4	12	#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
e8439270 KK	13	#include <linux/module.h>
	14	#include <linux/skbuff.h>
	15	#include <linux/ip.h>
	16	#include <net/checksum.h>
	17	#include <net/udp.h>
93742cf8	18	#include <net/tcp.h>
e8439270	19	#include <net/inet_sock.h>
93742cf8	20	#include <net/inet_hashtables.h>
cc6eb433	21	#include <linux/inetdevice.h>
e8439270 KK	22	#include <linux/netfilter/x_tables.h>
e8439270 KK	23	#include <linux/netfilter_ipv4/ip_tables.h>
e8439270 KK	24
e8439270 KK	25	#include <net/netfilter/ipv4/nf_defrag_ipv4.h>
f6318e55	26
c0cd1156	27	#if IS_ENABLED(CONFIG_IP6_NF_IPTABLES)
f6318e55	28	#define XT_TPROXY_HAVE_IPV6 1
cc6eb433 BS	29	#include <net/if_inet6.h>
cc6eb433 BS	30	#include <net/addrconf.h>
93742cf8	31	#include <net/inet6_hashtables.h>
cc6eb433	32	#include <linux/netfilter_ipv6/ip6_tables.h>
6ad78893	33	#include <net/netfilter/ipv6/nf_defrag_ipv6.h>
cc6eb433 BS	34	#endif
cc6eb433 BS	35
cc6eb433 BS	36	#include <linux/netfilter/xt_TPROXY.h>
cc6eb433 BS	37
93742cf8 FW	38	enum nf_tproxy_lookup_t {
	39	NFT_LOOKUP_LISTENER,
	40	NFT_LOOKUP_ESTABLISHED,
	41	};
	42
d503b30b FW	43	static bool tproxy_sk_is_transparent(struct sock *sk)
d503b30b FW	44	{
8b580147 ED	45	switch (sk->sk_state) {
8b580147 ED	46	case TCP_TIME_WAIT:
d503b30b FW	47	if (inet_twsk(sk)->tw_transparent)
d503b30b FW	48	return true;
8b580147 ED	49	break;
	50	case TCP_NEW_SYN_RECV:
	51	if (inet_rsk(inet_reqsk(sk))->no_srccheck)
	52	return true;
	53	break;
	54	default:
	55	if (inet_sk(sk)->transparent)
	56	return true;
d503b30b	57	}
8b580147 ED	58
8b580147 ED	59	sock_gen_put(sk);
d503b30b FW	60	return false;
	61	}
	62
cc6eb433 BS	63	static inline __be32
	64	tproxy_laddr4(struct sk_buff *skb, __be32 user_laddr, __be32 daddr)
	65	{
	66	struct in_device *indev;
	67	__be32 laddr;
	68
	69	if (user_laddr)
	70	return user_laddr;
	71
	72	laddr = 0;
	73	rcu_read_lock();
	74	indev = __in_dev_get_rcu(skb->dev);
	75	for_primary_ifa(indev) {
	76	laddr = ifa->ifa_local;
	77	break;
	78	} endfor_ifa(indev);
	79	rcu_read_unlock();
	80
	81	return laddr ? laddr : daddr;
	82	}
e8439270	83
93742cf8 FW	84	/*
	85	* This is used when the user wants to intercept a connection matching
	86	* an explicit iptables rule. In this case the sockets are assumed
	87	* matching in preference order:
	88	*
	89	* - match: if there's a fully established connection matching the
	90	* _packet_ tuple, it is returned, assuming the redirection
	91	* already took place and we process a packet belonging to an
	92	* established connection
	93	*
	94	* - match: if there's a listening socket matching the redirection
	95	* (e.g. on-port & on-ip of the connection), it is returned,
	96	* regardless if it was bound to 0.0.0.0 or an explicit
	97	* address. The reasoning is that if there's an explicit rule, it
	98	* does not really matter if the listener is bound to an interface
	99	* or to 0. The user already stated that he wants redirection
	100	* (since he added the rule).
	101	*
	102	* Please note that there's an overlap between what a TPROXY target
	103	* and a socket match will match. Normally if you have both rules the
	104	* "socket" match will be the first one, effectively all packets
	105	* belonging to established connections going through that one.
	106	*/
	107	static inline struct sock *
a583636a CG	108	nf_tproxy_get_sock_v4(struct net net, struct sk_buff skb, void *hp,
a583636a CG	109	const u8 protocol,
93742cf8 FW	110	const __be32 saddr, const __be32 daddr,
	111	const __be16 sport, const __be16 dport,
	112	const struct net_device *in,
	113	const enum nf_tproxy_lookup_t lookup_type)
	114	{
	115	struct sock *sk;
a583636a	116	struct tcphdr *tcph;
93742cf8 FW	117
	118	switch (protocol) {
	119	case IPPROTO_TCP:
	120	switch (lookup_type) {
	121	case NFT_LOOKUP_LISTENER:
a583636a CG	122	tcph = hp;
	123	sk = inet_lookup_listener(net, &tcp_hashinfo, skb,
	124	ip_hdrlen(skb) +
	125	__tcp_hdrlen(tcph),
93742cf8 FW	126	saddr, sport,
	127	daddr, dport,
	128	in->ifindex);
	129
41c6d650	130	if (sk && !refcount_inc_not_zero(&sk->sk_refcnt))
dcbe3590	131	sk = NULL;
93742cf8 FW	132	/* NOTE: we return listeners even if bound to
	133	* 0.0.0.0, those are filtered out in
	134	* xt_socket, since xt_TPROXY needs 0 bound
	135	* listeners too
	136	*/
	137	break;
	138	case NFT_LOOKUP_ESTABLISHED:
	139	sk = inet_lookup_established(net, &tcp_hashinfo,
	140	saddr, sport, daddr, dport,
	141	in->ifindex);
	142	break;
	143	default:
	144	BUG();
	145	}
	146	break;
	147	case IPPROTO_UDP:
	148	sk = udp4_lib_lookup(net, saddr, sport, daddr, dport,
	149	in->ifindex);
	150	if (sk) {
	151	int connected = (sk->sk_state == TCP_ESTABLISHED);
	152	int wildcard = (inet_sk(sk)->inet_rcv_saddr == 0);
	153
	154	/* NOTE: we return listeners even if bound to
	155	* 0.0.0.0, those are filtered out in
	156	* xt_socket, since xt_TPROXY needs 0 bound
	157	* listeners too
	158	*/
	159	if ((lookup_type == NFT_LOOKUP_ESTABLISHED && (!connected \|\| wildcard)) \|\|
	160	(lookup_type == NFT_LOOKUP_LISTENER && connected)) {
	161	sock_put(sk);
	162	sk = NULL;
	163	}
	164	}
	165	break;
	166	default:
	167	WARN_ON(1);
	168	sk = NULL;
	169	}
	170
	171	pr_debug("tproxy socket lookup: proto %u %08x:%u -> %08x:%u, lookup type: %d, sock %p\n",
	172	protocol, ntohl(saddr), ntohs(sport), ntohl(daddr), ntohs(dport), lookup_type, sk);
	173
	174	return sk;
	175	}
	176
d8b3bfc2	177	#ifdef XT_TPROXY_HAVE_IPV6
93742cf8	178	static inline struct sock *
a583636a CG	179	nf_tproxy_get_sock_v6(struct net net, struct sk_buff skb, int thoff, void *hp,
a583636a CG	180	const u8 protocol,
93742cf8 FW	181	const struct in6_addr saddr, const struct in6_addr daddr,
	182	const __be16 sport, const __be16 dport,
	183	const struct net_device *in,
	184	const enum nf_tproxy_lookup_t lookup_type)
	185	{
	186	struct sock *sk;
a583636a	187	struct tcphdr *tcph;
93742cf8 FW	188
	189	switch (protocol) {
	190	case IPPROTO_TCP:
	191	switch (lookup_type) {
	192	case NFT_LOOKUP_LISTENER:
a583636a CG	193	tcph = hp;
	194	sk = inet6_lookup_listener(net, &tcp_hashinfo, skb,
	195	thoff + __tcp_hdrlen(tcph),
93742cf8 FW	196	saddr, sport,
	197	daddr, ntohs(dport),
	198	in->ifindex);
	199
41c6d650	200	if (sk && !refcount_inc_not_zero(&sk->sk_refcnt))
dcbe3590	201	sk = NULL;
93742cf8 FW	202	/* NOTE: we return listeners even if bound to
	203	* 0.0.0.0, those are filtered out in
	204	* xt_socket, since xt_TPROXY needs 0 bound
	205	* listeners too
	206	*/
	207	break;
	208	case NFT_LOOKUP_ESTABLISHED:
	209	sk = __inet6_lookup_established(net, &tcp_hashinfo,
	210	saddr, sport, daddr, ntohs(dport),
	211	in->ifindex);
	212	break;
	213	default:
	214	BUG();
	215	}
	216	break;
	217	case IPPROTO_UDP:
	218	sk = udp6_lib_lookup(net, saddr, sport, daddr, dport,
	219	in->ifindex);
	220	if (sk) {
	221	int connected = (sk->sk_state == TCP_ESTABLISHED);
efe4208f	222	int wildcard = ipv6_addr_any(&sk->sk_v6_rcv_saddr);
93742cf8 FW	223
	224	/* NOTE: we return listeners even if bound to
	225	* 0.0.0.0, those are filtered out in
	226	* xt_socket, since xt_TPROXY needs 0 bound
	227	* listeners too
	228	*/
	229	if ((lookup_type == NFT_LOOKUP_ESTABLISHED && (!connected \|\| wildcard)) \|\|
	230	(lookup_type == NFT_LOOKUP_LISTENER && connected)) {
	231	sock_put(sk);
	232	sk = NULL;
	233	}
	234	}
	235	break;
	236	default:
	237	WARN_ON(1);
	238	sk = NULL;
	239	}
	240
	241	pr_debug("tproxy socket lookup: proto %u %pI6:%u -> %pI6:%u, lookup type: %d, sock %p\n",
	242	protocol, saddr, ntohs(sport), daddr, ntohs(dport), lookup_type, sk);
	243
	244	return sk;
	245	}
	246	#endif
	247
106e4c26	248	/**
2c53040f	249	* tproxy_handle_time_wait4 - handle IPv4 TCP TIME_WAIT reopen redirections
106e4c26	250	* @skb: The skb being processed.
6ad78893 BS	251	* @laddr: IPv4 address to redirect to or zero.
6ad78893 BS	252	* @lport: TCP port to redirect to or zero.
106e4c26 BS	253	* @sk: The TIME_WAIT TCP socket found by the lookup.
	254	*
	255	* We have to handle SYN packets arriving to TIME_WAIT sockets
	256	* differently: instead of reopening the connection we should rather
	257	* redirect the new connection to the proxy if there's a listener
	258	* socket present.
	259	*
6ad78893	260	* tproxy_handle_time_wait4() consumes the socket reference passed in.
106e4c26 BS	261	*
	262	* Returns the listener socket if there's one, the TIME_WAIT socket if
	263	* no such listener is found, or NULL if the TCP header is incomplete.
	264	*/
	265	static struct sock *
686c9b50 EB	266	tproxy_handle_time_wait4(struct net net, struct sk_buff skb,
686c9b50 EB	267	__be32 laddr, __be16 lport, struct sock *sk)
106e4c26 BS	268	{
106e4c26 BS	269	const struct iphdr *iph = ip_hdr(skb);
106e4c26 BS	270	struct tcphdr _hdr, *hp;
	271
	272	hp = skb_header_pointer(skb, ip_hdrlen(skb), sizeof(_hdr), &_hdr);
	273	if (hp == NULL) {
	274	inet_twsk_put(inet_twsk(sk));
	275	return NULL;
	276	}
	277
	278	if (hp->syn && !hp->rst && !hp->ack && !hp->fin) {
	279	/* SYN to a TIME_WAIT socket, we'd rather redirect it
	280	* to a listener socket if there's one */
	281	struct sock *sk2;
	282
a583636a	283	sk2 = nf_tproxy_get_sock_v4(net, skb, hp, iph->protocol,
6ad78893 BS	284	iph->saddr, laddr ? laddr : iph->daddr,
	285	hp->source, lport ? lport : hp->dest,
	286	skb->dev, NFT_LOOKUP_LISTENER);
	287	if (sk2) {
dbe7faa4	288	inet_twsk_deschedule_put(inet_twsk(sk));
6ad78893 BS	289	sk = sk2;
	290	}
	291	}
	292
	293	return sk;
	294	}
	295
fd158d79 FW	296	/* assign a socket to the skb -- consumes sk */
	297	static void
	298	nf_tproxy_assign_sock(struct sk_buff skb, struct sock sk)
	299	{
	300	skb_orphan(skb);
	301	skb->sk = sk;
	302	skb->destructor = sock_edemux;
	303	}
	304
e8439270	305	static unsigned int
686c9b50	306	tproxy_tg4(struct net net, struct sk_buff skb, __be32 laddr, __be16 lport,
6ad78893	307	u_int32_t mark_mask, u_int32_t mark_value)
e8439270 KK	308	{
e8439270 KK	309	const struct iphdr *iph = ip_hdr(skb);
e8439270 KK	310	struct udphdr _hdr, *hp;
	311	struct sock *sk;
	312
	313	hp = skb_header_pointer(skb, ip_hdrlen(skb), sizeof(_hdr), &_hdr);
	314	if (hp == NULL)
	315	return NF_DROP;
	316
6ad78893 BS	317	/* check if there's an ongoing connection on the packet
	318	* addresses, this happens if the redirect already happened
	319	* and the current packet belongs to an already established
	320	* connection */
a583636a	321	sk = nf_tproxy_get_sock_v4(net, skb, hp, iph->protocol,
106e4c26 BS	322	iph->saddr, iph->daddr,
106e4c26 BS	323	hp->source, hp->dest,
6ad78893	324	skb->dev, NFT_LOOKUP_ESTABLISHED);
106e4c26	325
cc6eb433 BS	326	laddr = tproxy_laddr4(skb, laddr, iph->daddr);
	327	if (!lport)
	328	lport = hp->dest;
	329
106e4c26 BS	330	/* UDP has no TCP_TIME_WAIT state, so we never enter here */
106e4c26 BS	331	if (sk && sk->sk_state == TCP_TIME_WAIT)
6ad78893	332	/* reopening a TIME_WAIT connection needs special handling */
686c9b50	333	sk = tproxy_handle_time_wait4(net, skb, laddr, lport, sk);
106e4c26	334	else if (!sk)
6ad78893 BS	335	/* no, there's no established connection, check if
6ad78893 BS	336	* there's a listener on the redirected addr/port */
a583636a	337	sk = nf_tproxy_get_sock_v4(net, skb, hp, iph->protocol,
cc6eb433 BS	338	iph->saddr, laddr,
cc6eb433 BS	339	hp->source, lport,
6ad78893 BS	340	skb->dev, NFT_LOOKUP_LISTENER);
	341
	342	/* NOTE: assign_sock consumes our sk reference */
d503b30b	343	if (sk && tproxy_sk_is_transparent(sk)) {
6ad78893 BS	344	/* This should be in a separate target, but we don't do multiple
	345	targets on the same rule yet */
	346	skb->mark = (skb->mark & ~mark_mask) ^ mark_value;
	347
	348	pr_debug("redirecting: proto %hhu %pI4:%hu -> %pI4:%hu, mark: %x\n",
	349	iph->protocol, &iph->daddr, ntohs(hp->dest),
	350	&laddr, ntohs(lport), skb->mark);
d503b30b FW	351
d503b30b FW	352	nf_tproxy_assign_sock(skb, sk);
6ad78893 BS	353	return NF_ACCEPT;
	354	}
	355
cc6eb433 BS	356	pr_debug("no socket, dropping: proto %hhu %pI4:%hu -> %pI4:%hu, mark: %x\n",
	357	iph->protocol, &iph->saddr, ntohs(hp->source),
	358	&iph->daddr, ntohs(hp->dest), skb->mark);
6ad78893 BS	359	return NF_DROP;
	360	}
	361
	362	static unsigned int
	363	tproxy_tg4_v0(struct sk_buff skb, const struct xt_action_param par)
	364	{
	365	const struct xt_tproxy_target_info *tgi = par->targinfo;
	366
613dbd95 PNA	367	return tproxy_tg4(xt_net(par), skb, tgi->laddr, tgi->lport,
613dbd95 PNA	368	tgi->mark_mask, tgi->mark_value);
6ad78893 BS	369	}
	370
	371	static unsigned int
	372	tproxy_tg4_v1(struct sk_buff skb, const struct xt_action_param par)
	373	{
	374	const struct xt_tproxy_target_info_v1 *tgi = par->targinfo;
	375
613dbd95 PNA	376	return tproxy_tg4(xt_net(par), skb, tgi->laddr.ip, tgi->lport,
613dbd95 PNA	377	tgi->mark_mask, tgi->mark_value);
6ad78893 BS	378	}
6ad78893 BS	379
f6318e55	380	#ifdef XT_TPROXY_HAVE_IPV6
cc6eb433 BS	381
	382	static inline const struct in6_addr *
	383	tproxy_laddr6(struct sk_buff skb, const struct in6_addr user_laddr,
	384	const struct in6_addr *daddr)
	385	{
	386	struct inet6_dev *indev;
	387	struct inet6_ifaddr *ifa;
	388	struct in6_addr *laddr;
	389
	390	if (!ipv6_addr_any(user_laddr))
	391	return user_laddr;
	392	laddr = NULL;
	393
	394	rcu_read_lock();
	395	indev = __in6_dev_get(skb->dev);
0c7930e5 LZ	396	if (indev) {
0c7930e5 LZ	397	read_lock_bh(&indev->lock);
cc6eb433 BS	398	list_for_each_entry(ifa, &indev->addr_list, if_list) {
	399	if (ifa->flags & (IFA_F_TENTATIVE \| IFA_F_DEPRECATED))
	400	continue;
	401
	402	laddr = &ifa->addr;
	403	break;
	404	}
0c7930e5 LZ	405	read_unlock_bh(&indev->lock);
0c7930e5 LZ	406	}
cc6eb433 BS	407	rcu_read_unlock();
	408
	409	return laddr ? laddr : daddr;
	410	}
	411
	412	/**
2c53040f	413	* tproxy_handle_time_wait6 - handle IPv6 TCP TIME_WAIT reopen redirections
cc6eb433 BS	414	* @skb: The skb being processed.
	415	* @tproto: Transport protocol.
	416	* @thoff: Transport protocol header offset.
	417	* @par: Iptables target parameters.
	418	* @sk: The TIME_WAIT TCP socket found by the lookup.
	419	*
	420	* We have to handle SYN packets arriving to TIME_WAIT sockets
	421	* differently: instead of reopening the connection we should rather
	422	* redirect the new connection to the proxy if there's a listener
	423	* socket present.
	424	*
	425	* tproxy_handle_time_wait6() consumes the socket reference passed in.
	426	*
	427	* Returns the listener socket if there's one, the TIME_WAIT socket if
	428	* no such listener is found, or NULL if the TCP header is incomplete.
	429	*/
	430	static struct sock *
	431	tproxy_handle_time_wait6(struct sk_buff *skb, int tproto, int thoff,
	432	const struct xt_action_param *par,
	433	struct sock *sk)
	434	{
	435	const struct ipv6hdr *iph = ipv6_hdr(skb);
	436	struct tcphdr _hdr, *hp;
	437	const struct xt_tproxy_target_info_v1 *tgi = par->targinfo;
	438
	439	hp = skb_header_pointer(skb, thoff, sizeof(_hdr), &_hdr);
	440	if (hp == NULL) {
	441	inet_twsk_put(inet_twsk(sk));
	442	return NULL;
	443	}
	444
	445	if (hp->syn && !hp->rst && !hp->ack && !hp->fin) {
	446	/* SYN to a TIME_WAIT socket, we'd rather redirect it
	447	* to a listener socket if there's one */
	448	struct sock *sk2;
	449
613dbd95	450	sk2 = nf_tproxy_get_sock_v6(xt_net(par), skb, thoff, hp, tproto,
cc6eb433 BS	451	&iph->saddr,
	452	tproxy_laddr6(skb, &tgi->laddr.in6, &iph->daddr),
	453	hp->source,
	454	tgi->lport ? tgi->lport : hp->dest,
	455	skb->dev, NFT_LOOKUP_LISTENER);
	456	if (sk2) {
dbe7faa4	457	inet_twsk_deschedule_put(inet_twsk(sk));
cc6eb433 BS	458	sk = sk2;
	459	}
	460	}
	461
	462	return sk;
	463	}
	464
6ad78893 BS	465	static unsigned int
	466	tproxy_tg6_v1(struct sk_buff skb, const struct xt_action_param par)
	467	{
	468	const struct ipv6hdr *iph = ipv6_hdr(skb);
	469	const struct xt_tproxy_target_info_v1 *tgi = par->targinfo;
	470	struct udphdr _hdr, *hp;
	471	struct sock *sk;
cc6eb433 BS	472	const struct in6_addr *laddr;
cc6eb433 BS	473	__be16 lport;
84018f55	474	int thoff = 0;
6ad78893 BS	475	int tproto;
6ad78893 BS	476
84018f55	477	tproto = ipv6_find_hdr(skb, &thoff, -1, NULL, NULL);
6ad78893 BS	478	if (tproto < 0) {
	479	pr_debug("unable to find transport header in IPv6 packet, dropping\n");
	480	return NF_DROP;
	481	}
	482
	483	hp = skb_header_pointer(skb, thoff, sizeof(_hdr), &_hdr);
	484	if (hp == NULL) {
	485	pr_debug("unable to grab transport header contents in IPv6 packet, dropping\n");
	486	return NF_DROP;
	487	}
	488
	489	/* check if there's an ongoing connection on the packet
	490	* addresses, this happens if the redirect already happened
	491	* and the current packet belongs to an already established
	492	* connection */
613dbd95	493	sk = nf_tproxy_get_sock_v6(xt_net(par), skb, thoff, hp, tproto,
6ad78893 BS	494	&iph->saddr, &iph->daddr,
6ad78893 BS	495	hp->source, hp->dest,
613dbd95	496	xt_in(par), NFT_LOOKUP_ESTABLISHED);
6ad78893	497
cc6eb433 BS	498	laddr = tproxy_laddr6(skb, &tgi->laddr.in6, &iph->daddr);
	499	lport = tgi->lport ? tgi->lport : hp->dest;
	500
6ad78893 BS	501	/* UDP has no TCP_TIME_WAIT state, so we never enter here */
	502	if (sk && sk->sk_state == TCP_TIME_WAIT)
	503	/* reopening a TIME_WAIT connection needs special handling */
	504	sk = tproxy_handle_time_wait6(skb, tproto, thoff, par, sk);
	505	else if (!sk)
	506	/* no there's no established connection, check if
	507	* there's a listener on the redirected addr/port */
613dbd95	508	sk = nf_tproxy_get_sock_v6(xt_net(par), skb, thoff, hp,
a583636a	509	tproto, &iph->saddr, laddr,
cc6eb433	510	hp->source, lport,
613dbd95	511	xt_in(par), NFT_LOOKUP_LISTENER);
e8439270 KK	512
e8439270 KK	513	/* NOTE: assign_sock consumes our sk reference */
d503b30b	514	if (sk && tproxy_sk_is_transparent(sk)) {
e8439270 KK	515	/* This should be in a separate target, but we don't do multiple
	516	targets on the same rule yet */
	517	skb->mark = (skb->mark & ~tgi->mark_mask) ^ tgi->mark_value;
	518
6ad78893	519	pr_debug("redirecting: proto %hhu %pI6:%hu -> %pI6:%hu, mark: %x\n",
cc6eb433 BS	520	tproto, &iph->saddr, ntohs(hp->source),
cc6eb433 BS	521	laddr, ntohs(lport), skb->mark);
d503b30b FW	522
d503b30b FW	523	nf_tproxy_assign_sock(skb, sk);
e8439270 KK	524	return NF_ACCEPT;
	525	}
	526
6ad78893	527	pr_debug("no socket, dropping: proto %hhu %pI6:%hu -> %pI6:%hu, mark: %x\n",
cc6eb433 BS	528	tproto, &iph->saddr, ntohs(hp->source),
	529	&iph->daddr, ntohs(hp->dest), skb->mark);
	530
e8439270 KK	531	return NF_DROP;
	532	}
	533
6ad78893 BS	534	static int tproxy_tg6_check(const struct xt_tgchk_param *par)
	535	{
	536	const struct ip6t_ip6 *i = par->entryinfo;
834184b1 FW	537	int err;
	538
	539	err = nf_defrag_ipv6_enable(par->net);
	540	if (err)
	541	return err;
6ad78893	542
3d8c6dce PNA	543	if ((i->proto == IPPROTO_TCP \|\| i->proto == IPPROTO_UDP) &&
3d8c6dce PNA	544	!(i->invflags & IP6T_INV_PROTO))
6ad78893 BS	545	return 0;
	546
	547	pr_info("Can be used only in combination with "
	548	"either -p tcp or -p udp\n");
	549	return -EINVAL;
	550	}
	551	#endif
	552
	553	static int tproxy_tg4_check(const struct xt_tgchk_param *par)
e8439270	554	{
af5d6dc2	555	const struct ipt_ip *i = par->entryinfo;
834184b1 FW	556	int err;
	557
	558	err = nf_defrag_ipv4_enable(par->net);
	559	if (err)
	560	return err;
e8439270 KK	561
	562	if ((i->proto == IPPROTO_TCP \|\| i->proto == IPPROTO_UDP)
	563	&& !(i->invflags & IPT_INV_PROTO))
d6b00a53	564	return 0;
e8439270	565
ff67e4e4	566	pr_info("Can be used only in combination with "
e8439270	567	"either -p tcp or -p udp\n");
d6b00a53	568	return -EINVAL;
e8439270 KK	569	}
e8439270 KK	570
6ad78893 BS	571	static struct xt_target tproxy_tg_reg[] __read_mostly = {
	572	{
	573	.name = "TPROXY",
	574	.family = NFPROTO_IPV4,
	575	.table = "mangle",
	576	.target = tproxy_tg4_v0,
	577	.revision = 0,
	578	.targetsize = sizeof(struct xt_tproxy_target_info),
	579	.checkentry = tproxy_tg4_check,
	580	.hooks = 1 << NF_INET_PRE_ROUTING,
	581	.me = THIS_MODULE,
	582	},
	583	{
	584	.name = "TPROXY",
	585	.family = NFPROTO_IPV4,
	586	.table = "mangle",
	587	.target = tproxy_tg4_v1,
	588	.revision = 1,
	589	.targetsize = sizeof(struct xt_tproxy_target_info_v1),
	590	.checkentry = tproxy_tg4_check,
	591	.hooks = 1 << NF_INET_PRE_ROUTING,
	592	.me = THIS_MODULE,
	593	},
f6318e55	594	#ifdef XT_TPROXY_HAVE_IPV6
6ad78893 BS	595	{
	596	.name = "TPROXY",
	597	.family = NFPROTO_IPV6,
	598	.table = "mangle",
	599	.target = tproxy_tg6_v1,
	600	.revision = 1,
	601	.targetsize = sizeof(struct xt_tproxy_target_info_v1),
	602	.checkentry = tproxy_tg6_check,
	603	.hooks = 1 << NF_INET_PRE_ROUTING,
	604	.me = THIS_MODULE,
	605	},
	606	#endif
	607
e8439270 KK	608	};
	609
	610	static int __init tproxy_tg_init(void)
	611	{
6ad78893	612	return xt_register_targets(tproxy_tg_reg, ARRAY_SIZE(tproxy_tg_reg));
e8439270 KK	613	}
	614
	615	static void __exit tproxy_tg_exit(void)
	616	{
6ad78893	617	xt_unregister_targets(tproxy_tg_reg, ARRAY_SIZE(tproxy_tg_reg));
e8439270 KK	618	}
	619
	620	module_init(tproxy_tg_init);
	621	module_exit(tproxy_tg_exit);
	622	MODULE_LICENSE("GPL");
6ad78893	623	MODULE_AUTHOR("Balazs Scheidler, Krisztian Kovacs");
e8439270 KK	624	MODULE_DESCRIPTION("Netfilter transparent proxy (TPROXY) target module.");
e8439270 KK	625	MODULE_ALIAS("ipt_TPROXY");
6ad78893	626	MODULE_ALIAS("ip6t_TPROXY");