[net-next-2.6.git] / net / netfilter / xt_socket.c

/*
 * Transparent proxy support for Linux/iptables
 *
 * Copyright (C) 2007-2008 BalaBit IT Ltd.
 * Author: 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/netfilter/x_tables.h>
#include <linux/netfilter_ipv4/ip_tables.h>
#include <net/tcp.h>
#include <net/udp.h>
#include <net/icmp.h>
#include <net/sock.h>
#include <net/inet_sock.h>
#include <net/netfilter/nf_tproxy_core.h>
#include <net/netfilter/ipv4/nf_defrag_ipv4.h>

#if defined(CONFIG_IP6_NF_IPTABLES) || defined(CONFIG_IP6_NF_IPTABLES_MODULE)
#define XT_SOCKET_HAVE_IPV6 1
#include <linux/netfilter_ipv6/ip6_tables.h>
#include <net/netfilter/ipv6/nf_defrag_ipv6.h>
#endif

#include <linux/netfilter/xt_socket.h>

#if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
#define XT_SOCKET_HAVE_CONNTRACK 1
#include <net/netfilter/nf_conntrack.h>
#endif

static int
extract_icmp4_fields(const struct sk_buff *skb,
		    u8 *protocol,
		    __be32 *raddr,
		    __be32 *laddr,
		    __be16 *rport,
		    __be16 *lport)
{
	unsigned int outside_hdrlen = ip_hdrlen(skb);
	struct iphdr *inside_iph, _inside_iph;
	struct icmphdr *icmph, _icmph;
	__be16 *ports, _ports[2];

	icmph = skb_header_pointer(skb, outside_hdrlen,
				   sizeof(_icmph), &_icmph);
	if (icmph == NULL)
		return 1;

	switch (icmph->type) {
	case ICMP_DEST_UNREACH:
	case ICMP_SOURCE_QUENCH:
	case ICMP_REDIRECT:
	case ICMP_TIME_EXCEEDED:
	case ICMP_PARAMETERPROB:
		break;
	default:
		return 1;
	}

	inside_iph = skb_header_pointer(skb, outside_hdrlen +
					sizeof(struct icmphdr),
					sizeof(_inside_iph), &_inside_iph);
	if (inside_iph == NULL)
		return 1;

	if (inside_iph->protocol != IPPROTO_TCP &&
	    inside_iph->protocol != IPPROTO_UDP)
		return 1;

	ports = skb_header_pointer(skb, outside_hdrlen +
				   sizeof(struct icmphdr) +
				   (inside_iph->ihl << 2),
				   sizeof(_ports), &_ports);
	if (ports == NULL)
		return 1;

	/* the inside IP packet is the one quoted from our side, thus
	 * its saddr is the local address */
	*protocol = inside_iph->protocol;
	*laddr = inside_iph->saddr;
	*lport = ports[0];
	*raddr = inside_iph->daddr;
	*rport = ports[1];

	return 0;
}

static bool
socket_match(const struct sk_buff *skb, struct xt_action_param *par,
	     const struct xt_socket_mtinfo1 *info)
{
	const struct iphdr *iph = ip_hdr(skb);
	struct udphdr _hdr, *hp = NULL;
	struct sock *sk;
	__be32 daddr, saddr;
	__be16 dport, sport;
	u8 protocol;
#ifdef XT_SOCKET_HAVE_CONNTRACK
	struct nf_conn const *ct;
	enum ip_conntrack_info ctinfo;
#endif

	if (iph->protocol == IPPROTO_UDP || iph->protocol == IPPROTO_TCP) {
		hp = skb_header_pointer(skb, ip_hdrlen(skb),
					sizeof(_hdr), &_hdr);
		if (hp == NULL)
			return false;

		protocol = iph->protocol;
		saddr = iph->saddr;
		sport = hp->source;
		daddr = iph->daddr;
		dport = hp->dest;

	} else if (iph->protocol == IPPROTO_ICMP) {
		if (extract_icmp4_fields(skb, &protocol, &saddr, &daddr,
					&sport, &dport))
			return false;
	} else {
		return false;
	}

#ifdef XT_SOCKET_HAVE_CONNTRACK
	/* Do the lookup with the original socket address in case this is a
	 * reply packet of an established SNAT-ted connection. */

	ct = nf_ct_get(skb, &ctinfo);
	if (ct && !nf_ct_is_untracked(ct) &&
	    ((iph->protocol != IPPROTO_ICMP &&
	      ctinfo == IP_CT_IS_REPLY + IP_CT_ESTABLISHED) ||
	     (iph->protocol == IPPROTO_ICMP &&
	      ctinfo == IP_CT_IS_REPLY + IP_CT_RELATED)) &&
	    (ct->status & IPS_SRC_NAT_DONE)) {

		daddr = ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.u3.ip;
		dport = (iph->protocol == IPPROTO_TCP) ?
			ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.u.tcp.port :
			ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.u.udp.port;
	}
#endif

	sk = nf_tproxy_get_sock_v4(dev_net(skb->dev), protocol,
				   saddr, daddr, sport, dport, par->in, NFT_LOOKUP_ANY);
	if (sk != NULL) {
		bool wildcard;
		bool transparent = true;

		/* Ignore sockets listening on INADDR_ANY */
		wildcard = (sk->sk_state != TCP_TIME_WAIT &&
			    inet_sk(sk)->inet_rcv_saddr == 0);

		/* Ignore non-transparent sockets,
		   if XT_SOCKET_TRANSPARENT is used */
		if (info && info->flags & XT_SOCKET_TRANSPARENT)
			transparent = ((sk->sk_state != TCP_TIME_WAIT &&
					inet_sk(sk)->transparent) ||
				       (sk->sk_state == TCP_TIME_WAIT &&
					inet_twsk(sk)->tw_transparent));

		nf_tproxy_put_sock(sk);

		if (wildcard || !transparent)
			sk = NULL;
	}

	pr_debug("proto %hhu %pI4:%hu -> %pI4:%hu (orig %pI4:%hu) sock %p\n",
		 protocol, &saddr, ntohs(sport),
		 &daddr, ntohs(dport),
		 &iph->daddr, hp ? ntohs(hp->dest) : 0, sk);

	return (sk != NULL);
}

static bool
socket_mt4_v0(const struct sk_buff *skb, struct xt_action_param *par)
{
	return socket_match(skb, par, NULL);
}

static bool
socket_mt4_v1(const struct sk_buff *skb, struct xt_action_param *par)
{
	return socket_match(skb, par, par->matchinfo);
}

#ifdef XT_SOCKET_HAVE_IPV6

static int
extract_icmp6_fields(const struct sk_buff *skb,
		     unsigned int outside_hdrlen,
		     u8 *protocol,
		     struct in6_addr **raddr,
		     struct in6_addr **laddr,
		     __be16 *rport,
		     __be16 *lport)
{
	struct ipv6hdr *inside_iph, _inside_iph;
	struct icmp6hdr *icmph, _icmph;
	__be16 *ports, _ports[2];
	u8 inside_nexthdr;
	int inside_hdrlen;

	icmph = skb_header_pointer(skb, outside_hdrlen,
				   sizeof(_icmph), &_icmph);
	if (icmph == NULL)
		return 1;

	if (icmph->icmp6_type & ICMPV6_INFOMSG_MASK)
		return 1;

	inside_iph = skb_header_pointer(skb, outside_hdrlen + sizeof(_icmph), sizeof(_inside_iph), &_inside_iph);
	if (inside_iph == NULL)
		return 1;
	inside_nexthdr = inside_iph->nexthdr;

	inside_hdrlen = ipv6_skip_exthdr(skb, outside_hdrlen + sizeof(_icmph) + sizeof(_inside_iph), &inside_nexthdr);
	if (inside_hdrlen < 0)
		return 1; /* hjm: Packet has no/incomplete transport layer headers. */

	if (inside_nexthdr != IPPROTO_TCP &&
	    inside_nexthdr != IPPROTO_UDP)
		return 1;

	ports = skb_header_pointer(skb, inside_hdrlen,
				   sizeof(_ports), &_ports);
	if (ports == NULL)
		return 1;

	/* the inside IP packet is the one quoted from our side, thus
	 * its saddr is the local address */
	*protocol = inside_nexthdr;
	*laddr = &inside_iph->saddr;
	*lport = ports[0];
	*raddr = &inside_iph->daddr;
	*rport = ports[1];

	return 0;
}

static bool
socket_mt6_v1(const struct sk_buff *skb, struct xt_action_param *par)
{
	struct ipv6hdr *iph = ipv6_hdr(skb);
	struct udphdr _hdr, *hp = NULL;
	struct sock *sk;
	struct in6_addr *daddr, *saddr;
	__be16 dport, sport;
	int thoff;
	u8 tproto;
	const struct xt_socket_mtinfo1 *info = (struct xt_socket_mtinfo1 *) par->matchinfo;

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

	if (tproto == IPPROTO_UDP || tproto == IPPROTO_TCP) {
		hp = skb_header_pointer(skb, thoff,
					sizeof(_hdr), &_hdr);
		if (hp == NULL)
			return false;

		saddr = &iph->saddr;
		sport = hp->source;
		daddr = &iph->daddr;
		dport = hp->dest;

	} else if (tproto == IPPROTO_ICMPV6) {
		if (extract_icmp6_fields(skb, thoff, &tproto, &saddr, &daddr,
					 &sport, &dport))
			return false;
	} else {
		return false;
	}

	sk = nf_tproxy_get_sock_v6(dev_net(skb->dev), tproto,
				   saddr, daddr, sport, dport, par->in, NFT_LOOKUP_ANY);
	if (sk != NULL) {
		bool wildcard;
		bool transparent = true;

		/* Ignore sockets listening on INADDR_ANY */
		wildcard = (sk->sk_state != TCP_TIME_WAIT &&
			    ipv6_addr_any(&inet6_sk(sk)->rcv_saddr));

		/* Ignore non-transparent sockets,
		   if XT_SOCKET_TRANSPARENT is used */
		if (info && info->flags & XT_SOCKET_TRANSPARENT)
			transparent = ((sk->sk_state != TCP_TIME_WAIT &&
					inet_sk(sk)->transparent) ||
				       (sk->sk_state == TCP_TIME_WAIT &&
					inet_twsk(sk)->tw_transparent));

		nf_tproxy_put_sock(sk);

		if (wildcard || !transparent)
			sk = NULL;
	}

	pr_debug("proto %hhu %pI6:%hu -> %pI6:%hu "
		 "(orig %pI6:%hu) sock %p\n",
		 tproto, saddr, ntohs(sport),
		 daddr, ntohs(dport),
		 &iph->daddr, hp ? ntohs(hp->dest) : 0, sk);

	return (sk != NULL);
}
#endif

static struct xt_match socket_mt_reg[] __read_mostly = {
	{
		.name		= "socket",
		.revision	= 0,
		.family		= NFPROTO_IPV4,
		.match		= socket_mt4_v0,
		.hooks		= (1 << NF_INET_PRE_ROUTING) |
				  (1 << NF_INET_LOCAL_IN),
		.me		= THIS_MODULE,
	},
	{
		.name		= "socket",
		.revision	= 1,
		.family		= NFPROTO_IPV4,
		.match		= socket_mt4_v1,
		.matchsize	= sizeof(struct xt_socket_mtinfo1),
		.hooks		= (1 << NF_INET_PRE_ROUTING) |
				  (1 << NF_INET_LOCAL_IN),
		.me		= THIS_MODULE,
	},
#ifdef XT_SOCKET_HAVE_IPV6
	{
		.name		= "socket",
		.revision	= 1,
		.family		= NFPROTO_IPV6,
		.match		= socket_mt6_v1,
		.matchsize	= sizeof(struct xt_socket_mtinfo1),
		.hooks		= (1 << NF_INET_PRE_ROUTING) |
				  (1 << NF_INET_LOCAL_IN),
		.me		= THIS_MODULE,
	},
#endif
};

static int __init socket_mt_init(void)
{
	nf_defrag_ipv4_enable();
#ifdef XT_SOCKET_HAVE_IPV6
	nf_defrag_ipv6_enable();
#endif

	return xt_register_matches(socket_mt_reg, ARRAY_SIZE(socket_mt_reg));
}

static void __exit socket_mt_exit(void)
{
	xt_unregister_matches(socket_mt_reg, ARRAY_SIZE(socket_mt_reg));
}

module_init(socket_mt_init);
module_exit(socket_mt_exit);

MODULE_LICENSE("GPL");
MODULE_AUTHOR("Krisztian Kovacs, Balazs Scheidler");
MODULE_DESCRIPTION("x_tables socket match module");
MODULE_ALIAS("ipt_socket");
MODULE_ALIAS("ip6t_socket");
Commit	Line	Data
136cdc71 KK	1	/*
	2	* Transparent proxy support for Linux/iptables
	3	*
	4	* Copyright (C) 2007-2008 BalaBit IT Ltd.
	5	* Author: 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
136cdc71 KK	13	#include <linux/module.h>
	14	#include <linux/skbuff.h>
	15	#include <linux/netfilter/x_tables.h>
	16	#include <linux/netfilter_ipv4/ip_tables.h>
	17	#include <net/tcp.h>
	18	#include <net/udp.h>
	19	#include <net/icmp.h>
	20	#include <net/sock.h>
	21	#include <net/inet_sock.h>
	22	#include <net/netfilter/nf_tproxy_core.h>
	23	#include <net/netfilter/ipv4/nf_defrag_ipv4.h>
f6318e55 KK	24
	25	#if defined(CONFIG_IP6_NF_IPTABLES) \|\| defined(CONFIG_IP6_NF_IPTABLES_MODULE)
	26	#define XT_SOCKET_HAVE_IPV6 1
	27	#include <linux/netfilter_ipv6/ip6_tables.h>
b64c9256	28	#include <net/netfilter/ipv6/nf_defrag_ipv6.h>
f6318e55	29	#endif
136cdc71	30
a31e1ffd LAT	31	#include <linux/netfilter/xt_socket.h>
a31e1ffd LAT	32
136cdc71 KK	33	#if defined(CONFIG_NF_CONNTRACK) \|\| defined(CONFIG_NF_CONNTRACK_MODULE)
	34	#define XT_SOCKET_HAVE_CONNTRACK 1
	35	#include <net/netfilter/nf_conntrack.h>
	36	#endif
	37
	38	static int
b64c9256	39	extract_icmp4_fields(const struct sk_buff *skb,
136cdc71 KK	40	u8 *protocol,
	41	__be32 *raddr,
	42	__be32 *laddr,
	43	__be16 *rport,
	44	__be16 *lport)
	45	{
	46	unsigned int outside_hdrlen = ip_hdrlen(skb);
	47	struct iphdr *inside_iph, _inside_iph;
	48	struct icmphdr *icmph, _icmph;
	49	__be16 *ports, _ports[2];
	50
	51	icmph = skb_header_pointer(skb, outside_hdrlen,
	52	sizeof(_icmph), &_icmph);
	53	if (icmph == NULL)
	54	return 1;
	55
	56	switch (icmph->type) {
	57	case ICMP_DEST_UNREACH:
	58	case ICMP_SOURCE_QUENCH:
	59	case ICMP_REDIRECT:
	60	case ICMP_TIME_EXCEEDED:
	61	case ICMP_PARAMETERPROB:
	62	break;
	63	default:
	64	return 1;
	65	}
	66
	67	inside_iph = skb_header_pointer(skb, outside_hdrlen +
	68	sizeof(struct icmphdr),
	69	sizeof(_inside_iph), &_inside_iph);
	70	if (inside_iph == NULL)
	71	return 1;
	72
	73	if (inside_iph->protocol != IPPROTO_TCP &&
	74	inside_iph->protocol != IPPROTO_UDP)
	75	return 1;
	76
	77	ports = skb_header_pointer(skb, outside_hdrlen +
	78	sizeof(struct icmphdr) +
	79	(inside_iph->ihl << 2),
	80	sizeof(_ports), &_ports);
	81	if (ports == NULL)
	82	return 1;
	83
	84	/* the inside IP packet is the one quoted from our side, thus
	85	* its saddr is the local address */
	86	*protocol = inside_iph->protocol;
	87	*laddr = inside_iph->saddr;
	88	*lport = ports[0];
	89	*raddr = inside_iph->daddr;
	90	*rport = ports[1];
	91
	92	return 0;
	93	}
	94
136cdc71	95	static bool
62fc8051	96	socket_match(const struct sk_buff skb, struct xt_action_param par,
a31e1ffd	97	const struct xt_socket_mtinfo1 *info)
136cdc71 KK	98	{
	99	const struct iphdr *iph = ip_hdr(skb);
	100	struct udphdr _hdr, *hp = NULL;
	101	struct sock *sk;
	102	__be32 daddr, saddr;
	103	__be16 dport, sport;
	104	u8 protocol;
	105	#ifdef XT_SOCKET_HAVE_CONNTRACK
	106	struct nf_conn const *ct;
	107	enum ip_conntrack_info ctinfo;
	108	#endif
	109
	110	if (iph->protocol == IPPROTO_UDP \|\| iph->protocol == IPPROTO_TCP) {
	111	hp = skb_header_pointer(skb, ip_hdrlen(skb),
	112	sizeof(_hdr), &_hdr);
	113	if (hp == NULL)
	114	return false;
	115
	116	protocol = iph->protocol;
	117	saddr = iph->saddr;
	118	sport = hp->source;
	119	daddr = iph->daddr;
	120	dport = hp->dest;
	121
	122	} else if (iph->protocol == IPPROTO_ICMP) {
b64c9256	123	if (extract_icmp4_fields(skb, &protocol, &saddr, &daddr,
136cdc71 KK	124	&sport, &dport))
	125	return false;
	126	} else {
	127	return false;
	128	}
	129
	130	#ifdef XT_SOCKET_HAVE_CONNTRACK
	131	/* Do the lookup with the original socket address in case this is a
	132	* reply packet of an established SNAT-ted connection. */
	133
	134	ct = nf_ct_get(skb, &ctinfo);
5bfddbd4	135	if (ct && !nf_ct_is_untracked(ct) &&
136cdc71 KK	136	((iph->protocol != IPPROTO_ICMP &&
	137	ctinfo == IP_CT_IS_REPLY + IP_CT_ESTABLISHED) \|\|
	138	(iph->protocol == IPPROTO_ICMP &&
	139	ctinfo == IP_CT_IS_REPLY + IP_CT_RELATED)) &&
	140	(ct->status & IPS_SRC_NAT_DONE)) {
	141
	142	daddr = ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.u3.ip;
	143	dport = (iph->protocol == IPPROTO_TCP) ?
	144	ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.u.tcp.port :
	145	ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.u.udp.port;
	146	}
	147	#endif
	148
	149	sk = nf_tproxy_get_sock_v4(dev_net(skb->dev), protocol,
106e4c26	150	saddr, daddr, sport, dport, par->in, NFT_LOOKUP_ANY);
136cdc71	151	if (sk != NULL) {
a31e1ffd LAT	152	bool wildcard;
	153	bool transparent = true;
	154
	155	/* Ignore sockets listening on INADDR_ANY */
	156	wildcard = (sk->sk_state != TCP_TIME_WAIT &&
c720c7e8	157	inet_sk(sk)->inet_rcv_saddr == 0);
a31e1ffd LAT	158
	159	/* Ignore non-transparent sockets,
	160	if XT_SOCKET_TRANSPARENT is used */
	161	if (info && info->flags & XT_SOCKET_TRANSPARENT)
	162	transparent = ((sk->sk_state != TCP_TIME_WAIT &&
	163	inet_sk(sk)->transparent) \|\|
	164	(sk->sk_state == TCP_TIME_WAIT &&
	165	inet_twsk(sk)->tw_transparent));
136cdc71 KK	166
136cdc71 KK	167	nf_tproxy_put_sock(sk);
a31e1ffd LAT	168
a31e1ffd LAT	169	if (wildcard \|\| !transparent)
136cdc71 KK	170	sk = NULL;
	171	}
	172
b64c9256 BS	173	pr_debug("proto %hhu %pI4:%hu -> %pI4:%hu (orig %pI4:%hu) sock %p\n",
	174	protocol, &saddr, ntohs(sport),
	175	&daddr, ntohs(dport),
	176	&iph->daddr, hp ? ntohs(hp->dest) : 0, sk);
136cdc71 KK	177
	178	return (sk != NULL);
	179	}
	180
a31e1ffd	181	static bool
b64c9256	182	socket_mt4_v0(const struct sk_buff skb, struct xt_action_param par)
a31e1ffd LAT	183	{
	184	return socket_match(skb, par, NULL);
	185	}
	186
	187	static bool
b64c9256	188	socket_mt4_v1(const struct sk_buff skb, struct xt_action_param par)
a31e1ffd LAT	189	{
	190	return socket_match(skb, par, par->matchinfo);
	191	}
	192
f6318e55	193	#ifdef XT_SOCKET_HAVE_IPV6
b64c9256 BS	194
	195	static int
	196	extract_icmp6_fields(const struct sk_buff *skb,
	197	unsigned int outside_hdrlen,
	198	u8 *protocol,
	199	struct in6_addr **raddr,
	200	struct in6_addr **laddr,
	201	__be16 *rport,
	202	__be16 *lport)
	203	{
	204	struct ipv6hdr *inside_iph, _inside_iph;
	205	struct icmp6hdr *icmph, _icmph;
	206	__be16 *ports, _ports[2];
	207	u8 inside_nexthdr;
	208	int inside_hdrlen;
	209
	210	icmph = skb_header_pointer(skb, outside_hdrlen,
	211	sizeof(_icmph), &_icmph);
	212	if (icmph == NULL)
	213	return 1;
	214
	215	if (icmph->icmp6_type & ICMPV6_INFOMSG_MASK)
	216	return 1;
	217
	218	inside_iph = skb_header_pointer(skb, outside_hdrlen + sizeof(_icmph), sizeof(_inside_iph), &_inside_iph);
	219	if (inside_iph == NULL)
	220	return 1;
	221	inside_nexthdr = inside_iph->nexthdr;
	222
	223	inside_hdrlen = ipv6_skip_exthdr(skb, outside_hdrlen + sizeof(_icmph) + sizeof(_inside_iph), &inside_nexthdr);
	224	if (inside_hdrlen < 0)
	225	return 1; /* hjm: Packet has no/incomplete transport layer headers. */
	226
	227	if (inside_nexthdr != IPPROTO_TCP &&
	228	inside_nexthdr != IPPROTO_UDP)
	229	return 1;
	230
	231	ports = skb_header_pointer(skb, inside_hdrlen,
	232	sizeof(_ports), &_ports);
	233	if (ports == NULL)
	234	return 1;
	235
	236	/* the inside IP packet is the one quoted from our side, thus
	237	* its saddr is the local address */
	238	*protocol = inside_nexthdr;
	239	*laddr = &inside_iph->saddr;
	240	*lport = ports[0];
	241	*raddr = &inside_iph->daddr;
	242	*rport = ports[1];
	243
	244	return 0;
	245	}
	246
	247	static bool
	248	socket_mt6_v1(const struct sk_buff skb, struct xt_action_param par)
	249	{
	250	struct ipv6hdr *iph = ipv6_hdr(skb);
	251	struct udphdr _hdr, *hp = NULL;
	252	struct sock *sk;
	253	struct in6_addr daddr, saddr;
	254	__be16 dport, sport;
	255	int thoff;
	256	u8 tproto;
	257	const struct xt_socket_mtinfo1 info = (struct xt_socket_mtinfo1 ) par->matchinfo;
258
259	tproto = ipv6_find_hdr(skb, &thoff, -1, NULL);
260	if (tproto < 0) {
261	pr_debug("unable to find transport header in IPv6 packet, dropping\n");
262	return NF_DROP;
263	}
264
265	if (tproto == IPPROTO_UDP \|\| tproto == IPPROTO_TCP) {
266	hp = skb_header_pointer(skb, thoff,
267	sizeof(_hdr), &_hdr);
268	if (hp == NULL)
269	return false;
270
271	saddr = &iph->saddr;
272	sport = hp->source;
273	daddr = &iph->daddr;
274	dport = hp->dest;
275
276	} else if (tproto == IPPROTO_ICMPV6) {
277	if (extract_icmp6_fields(skb, thoff, &tproto, &saddr, &daddr,
278	&sport, &dport))
279	return false;
280	} else {
281	return false;
282	}
283
284	sk = nf_tproxy_get_sock_v6(dev_net(skb->dev), tproto,
285	saddr, daddr, sport, dport, par->in, NFT_LOOKUP_ANY);
286	if (sk != NULL) {
287	bool wildcard;
288	bool transparent = true;
289
290	/* Ignore sockets listening on INADDR_ANY */
291	wildcard = (sk->sk_state != TCP_TIME_WAIT &&
292	ipv6_addr_any(&inet6_sk(sk)->rcv_saddr));
293
294	/* Ignore non-transparent sockets,
295	if XT_SOCKET_TRANSPARENT is used */
296	if (info && info->flags & XT_SOCKET_TRANSPARENT)
297	transparent = ((sk->sk_state != TCP_TIME_WAIT &&
298	inet_sk(sk)->transparent) \|\|
299	(sk->sk_state == TCP_TIME_WAIT &&
300	inet_twsk(sk)->tw_transparent));
301
302	nf_tproxy_put_sock(sk);
303
304	if (wildcard \|\| !transparent)
305	sk = NULL;
306	}
307
308	pr_debug("proto %hhu %pI6:%hu -> %pI6:%hu "
309	"(orig %pI6:%hu) sock %p\n",
310	tproto, saddr, ntohs(sport),
311	daddr, ntohs(dport),
312	&iph->daddr, hp ? ntohs(hp->dest) : 0, sk);
313
314	return (sk != NULL);
315	}
316	#endif
317
a31e1ffd LAT	318	static struct xt_match socket_mt_reg[] __read_mostly = {
	319	{
	320	.name = "socket",
	321	.revision = 0,
	322	.family = NFPROTO_IPV4,
b64c9256	323	.match = socket_mt4_v0,
aa3c487f JE	324	.hooks = (1 << NF_INET_PRE_ROUTING) \|
aa3c487f JE	325	(1 << NF_INET_LOCAL_IN),
a31e1ffd LAT	326	.me = THIS_MODULE,
	327	},
	328	{
	329	.name = "socket",
	330	.revision = 1,
	331	.family = NFPROTO_IPV4,
b64c9256	332	.match = socket_mt4_v1,
a31e1ffd	333	.matchsize = sizeof(struct xt_socket_mtinfo1),
aa3c487f JE	334	.hooks = (1 << NF_INET_PRE_ROUTING) \|
aa3c487f JE	335	(1 << NF_INET_LOCAL_IN),
a31e1ffd LAT	336	.me = THIS_MODULE,
a31e1ffd LAT	337	},
f6318e55	338	#ifdef XT_SOCKET_HAVE_IPV6
b64c9256 BS	339	{
	340	.name = "socket",
	341	.revision = 1,
	342	.family = NFPROTO_IPV6,
	343	.match = socket_mt6_v1,
	344	.matchsize = sizeof(struct xt_socket_mtinfo1),
	345	.hooks = (1 << NF_INET_PRE_ROUTING) \|
	346	(1 << NF_INET_LOCAL_IN),
	347	.me = THIS_MODULE,
	348	},
	349	#endif
136cdc71 KK	350	};
	351
	352	static int __init socket_mt_init(void)
	353	{
	354	nf_defrag_ipv4_enable();
f6318e55	355	#ifdef XT_SOCKET_HAVE_IPV6
b64c9256 BS	356	nf_defrag_ipv6_enable();
	357	#endif
	358
a31e1ffd	359	return xt_register_matches(socket_mt_reg, ARRAY_SIZE(socket_mt_reg));
136cdc71 KK	360	}
	361
	362	static void __exit socket_mt_exit(void)
	363	{
a31e1ffd	364	xt_unregister_matches(socket_mt_reg, ARRAY_SIZE(socket_mt_reg));
136cdc71 KK	365	}
	366
	367	module_init(socket_mt_init);
	368	module_exit(socket_mt_exit);
	369
	370	MODULE_LICENSE("GPL");
	371	MODULE_AUTHOR("Krisztian Kovacs, Balazs Scheidler");
	372	MODULE_DESCRIPTION("x_tables socket match module");
	373	MODULE_ALIAS("ipt_socket");
b64c9256	374	MODULE_ALIAS("ip6t_socket");