[GitHub/mt8127/android_kernel_alcatel_ttab.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 IS_ENABLED(CONFIG_IP6_NF_IPTABLES)
#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 IS_ENABLED(CONFIG_NF_CONNTRACK)
#define XT_SOCKET_HAVE_CONNTRACK 1
#include <net/netfilter/nf_conntrack.h>
#endif

static void
xt_socket_put_sk(struct sock *sk)
{
	if (sk->sk_state == TCP_TIME_WAIT)
		inet_twsk_put(inet_twsk(sk));
	else
		sock_put(sk);
}

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 uninitialized_var(daddr), uninitialized_var(saddr);
	__be16 uninitialized_var(dport), uninitialized_var(sport);
	u8 uninitialized_var(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_ESTABLISHED_REPLY) ||
	     (iph->protocol == IPPROTO_ICMP &&
	      ctinfo == IP_CT_RELATED_REPLY)) &&
	    (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));

		xt_socket_put_sk(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,
		     int *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;
	__be16 inside_fragoff;
	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, &inside_fragoff);
	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 = NULL, *saddr = NULL;
	__be16 uninitialized_var(dport), uninitialized_var(sport);
	int thoff = 0, uninitialized_var(tproto);
	const struct xt_socket_mtinfo1 *info = (struct xt_socket_mtinfo1 *) par->matchinfo;

	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;
	}

	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));

		xt_socket_put_sk(sk);

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

	pr_debug("proto %hhd %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	24
c0cd1156	25	#if IS_ENABLED(CONFIG_IP6_NF_IPTABLES)
f6318e55 KK	26	#define XT_SOCKET_HAVE_IPV6 1
f6318e55 KK	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
c0cd1156	33	#if IS_ENABLED(CONFIG_NF_CONNTRACK)
136cdc71 KK	34	#define XT_SOCKET_HAVE_CONNTRACK 1
	35	#include <net/netfilter/nf_conntrack.h>
	36	#endif
	37
d503b30b FW	38	static void
	39	xt_socket_put_sk(struct sock *sk)
	40	{
	41	if (sk->sk_state == TCP_TIME_WAIT)
	42	inet_twsk_put(inet_twsk(sk));
	43	else
	44	sock_put(sk);
	45	}
	46
136cdc71	47	static int
b64c9256	48	extract_icmp4_fields(const struct sk_buff *skb,
136cdc71 KK	49	u8 *protocol,
	50	__be32 *raddr,
	51	__be32 *laddr,
	52	__be16 *rport,
	53	__be16 *lport)
	54	{
	55	unsigned int outside_hdrlen = ip_hdrlen(skb);
	56	struct iphdr *inside_iph, _inside_iph;
	57	struct icmphdr *icmph, _icmph;
	58	__be16 *ports, _ports[2];
	59
	60	icmph = skb_header_pointer(skb, outside_hdrlen,
	61	sizeof(_icmph), &_icmph);
	62	if (icmph == NULL)
	63	return 1;
	64
	65	switch (icmph->type) {
	66	case ICMP_DEST_UNREACH:
	67	case ICMP_SOURCE_QUENCH:
	68	case ICMP_REDIRECT:
	69	case ICMP_TIME_EXCEEDED:
	70	case ICMP_PARAMETERPROB:
	71	break;
	72	default:
	73	return 1;
	74	}
	75
	76	inside_iph = skb_header_pointer(skb, outside_hdrlen +
	77	sizeof(struct icmphdr),
	78	sizeof(_inside_iph), &_inside_iph);
	79	if (inside_iph == NULL)
	80	return 1;
	81
	82	if (inside_iph->protocol != IPPROTO_TCP &&
	83	inside_iph->protocol != IPPROTO_UDP)
	84	return 1;
	85
	86	ports = skb_header_pointer(skb, outside_hdrlen +
	87	sizeof(struct icmphdr) +
	88	(inside_iph->ihl << 2),
	89	sizeof(_ports), &_ports);
	90	if (ports == NULL)
	91	return 1;
	92
	93	/* the inside IP packet is the one quoted from our side, thus
	94	* its saddr is the local address */
	95	*protocol = inside_iph->protocol;
	96	*laddr = inside_iph->saddr;
	97	*lport = ports[0];
	98	*raddr = inside_iph->daddr;
	99	*rport = ports[1];
	100
	101	return 0;
	102	}
	103
136cdc71	104	static bool
62fc8051	105	socket_match(const struct sk_buff skb, struct xt_action_param par,
a31e1ffd	106	const struct xt_socket_mtinfo1 *info)
136cdc71 KK	107	{
	108	const struct iphdr *iph = ip_hdr(skb);
	109	struct udphdr _hdr, *hp = NULL;
	110	struct sock *sk;
6703aa74 PNA	111	__be32 uninitialized_var(daddr), uninitialized_var(saddr);
	112	__be16 uninitialized_var(dport), uninitialized_var(sport);
	113	u8 uninitialized_var(protocol);
136cdc71 KK	114	#ifdef XT_SOCKET_HAVE_CONNTRACK
	115	struct nf_conn const *ct;
	116	enum ip_conntrack_info ctinfo;
	117	#endif
	118
	119	if (iph->protocol == IPPROTO_UDP \|\| iph->protocol == IPPROTO_TCP) {
	120	hp = skb_header_pointer(skb, ip_hdrlen(skb),
	121	sizeof(_hdr), &_hdr);
	122	if (hp == NULL)
	123	return false;
	124
	125	protocol = iph->protocol;
	126	saddr = iph->saddr;
	127	sport = hp->source;
	128	daddr = iph->daddr;
	129	dport = hp->dest;
	130
	131	} else if (iph->protocol == IPPROTO_ICMP) {
b64c9256	132	if (extract_icmp4_fields(skb, &protocol, &saddr, &daddr,
136cdc71 KK	133	&sport, &dport))
	134	return false;
	135	} else {
	136	return false;
	137	}
	138
	139	#ifdef XT_SOCKET_HAVE_CONNTRACK
	140	/* Do the lookup with the original socket address in case this is a
	141	* reply packet of an established SNAT-ted connection. */
	142
	143	ct = nf_ct_get(skb, &ctinfo);
5bfddbd4	144	if (ct && !nf_ct_is_untracked(ct) &&
136cdc71	145	((iph->protocol != IPPROTO_ICMP &&
fb048833	146	ctinfo == IP_CT_ESTABLISHED_REPLY) \|\|
136cdc71	147	(iph->protocol == IPPROTO_ICMP &&
fb048833	148	ctinfo == IP_CT_RELATED_REPLY)) &&
136cdc71 KK	149	(ct->status & IPS_SRC_NAT_DONE)) {
	150
	151	daddr = ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.u3.ip;
	152	dport = (iph->protocol == IPPROTO_TCP) ?
	153	ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.u.tcp.port :
	154	ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.u.udp.port;
	155	}
	156	#endif
	157
	158	sk = nf_tproxy_get_sock_v4(dev_net(skb->dev), protocol,
106e4c26	159	saddr, daddr, sport, dport, par->in, NFT_LOOKUP_ANY);
136cdc71	160	if (sk != NULL) {
a31e1ffd LAT	161	bool wildcard;
	162	bool transparent = true;
	163
	164	/* Ignore sockets listening on INADDR_ANY */
	165	wildcard = (sk->sk_state != TCP_TIME_WAIT &&
c720c7e8	166	inet_sk(sk)->inet_rcv_saddr == 0);
a31e1ffd LAT	167
	168	/* Ignore non-transparent sockets,
	169	if XT_SOCKET_TRANSPARENT is used */
	170	if (info && info->flags & XT_SOCKET_TRANSPARENT)
	171	transparent = ((sk->sk_state != TCP_TIME_WAIT &&
	172	inet_sk(sk)->transparent) \|\|
	173	(sk->sk_state == TCP_TIME_WAIT &&
	174	inet_twsk(sk)->tw_transparent));
136cdc71	175
d503b30b	176	xt_socket_put_sk(sk);
a31e1ffd LAT	177
a31e1ffd LAT	178	if (wildcard \|\| !transparent)
136cdc71 KK	179	sk = NULL;
	180	}
	181
b64c9256 BS	182	pr_debug("proto %hhu %pI4:%hu -> %pI4:%hu (orig %pI4:%hu) sock %p\n",
	183	protocol, &saddr, ntohs(sport),
	184	&daddr, ntohs(dport),
	185	&iph->daddr, hp ? ntohs(hp->dest) : 0, sk);
136cdc71 KK	186
	187	return (sk != NULL);
	188	}
	189
a31e1ffd	190	static bool
b64c9256	191	socket_mt4_v0(const struct sk_buff skb, struct xt_action_param par)
a31e1ffd LAT	192	{
	193	return socket_match(skb, par, NULL);
	194	}
	195
	196	static bool
b64c9256	197	socket_mt4_v1(const struct sk_buff skb, struct xt_action_param par)
a31e1ffd LAT	198	{
	199	return socket_match(skb, par, par->matchinfo);
	200	}
	201
f6318e55	202	#ifdef XT_SOCKET_HAVE_IPV6
b64c9256 BS	203
	204	static int
	205	extract_icmp6_fields(const struct sk_buff *skb,
	206	unsigned int outside_hdrlen,
089282fb	207	int *protocol,
b64c9256 BS	208	struct in6_addr **raddr,
	209	struct in6_addr **laddr,
	210	__be16 *rport,
	211	__be16 *lport)
	212	{
	213	struct ipv6hdr *inside_iph, _inside_iph;
	214	struct icmp6hdr *icmph, _icmph;
	215	__be16 *ports, _ports[2];
	216	u8 inside_nexthdr;
75f2811c	217	__be16 inside_fragoff;
b64c9256 BS	218	int inside_hdrlen;
	219
	220	icmph = skb_header_pointer(skb, outside_hdrlen,
	221	sizeof(_icmph), &_icmph);
	222	if (icmph == NULL)
	223	return 1;
	224
	225	if (icmph->icmp6_type & ICMPV6_INFOMSG_MASK)
	226	return 1;
	227
	228	inside_iph = skb_header_pointer(skb, outside_hdrlen + sizeof(_icmph), sizeof(_inside_iph), &_inside_iph);
	229	if (inside_iph == NULL)
	230	return 1;
	231	inside_nexthdr = inside_iph->nexthdr;
	232
75f2811c JG	233	inside_hdrlen = ipv6_skip_exthdr(skb, outside_hdrlen + sizeof(_icmph) + sizeof(_inside_iph),
75f2811c JG	234	&inside_nexthdr, &inside_fragoff);
b64c9256 BS	235	if (inside_hdrlen < 0)
	236	return 1; /* hjm: Packet has no/incomplete transport layer headers. */
	237
	238	if (inside_nexthdr != IPPROTO_TCP &&
	239	inside_nexthdr != IPPROTO_UDP)
	240	return 1;
	241
	242	ports = skb_header_pointer(skb, inside_hdrlen,
	243	sizeof(_ports), &_ports);
	244	if (ports == NULL)
	245	return 1;
	246
	247	/* the inside IP packet is the one quoted from our side, thus
	248	* its saddr is the local address */
	249	*protocol = inside_nexthdr;
	250	*laddr = &inside_iph->saddr;
	251	*lport = ports[0];
	252	*raddr = &inside_iph->daddr;
	253	*rport = ports[1];
	254
	255	return 0;
	256	}
	257
	258	static bool
	259	socket_mt6_v1(const struct sk_buff skb, struct xt_action_param par)
	260	{
	261	struct ipv6hdr *iph = ipv6_hdr(skb);
	262	struct udphdr _hdr, *hp = NULL;
	263	struct sock *sk;
6703aa74 PNA	264	struct in6_addr daddr = NULL, saddr = NULL;
	265	__be16 uninitialized_var(dport), uninitialized_var(sport);
	266	int thoff = 0, uninitialized_var(tproto);
b64c9256 BS	267	const struct xt_socket_mtinfo1 info = (struct xt_socket_mtinfo1 ) par->matchinfo;
b64c9256 BS	268
84018f55	269	tproto = ipv6_find_hdr(skb, &thoff, -1, NULL, NULL);
b64c9256 BS	270	if (tproto < 0) {
	271	pr_debug("unable to find transport header in IPv6 packet, dropping\n");
	272	return NF_DROP;
	273	}
	274
	275	if (tproto == IPPROTO_UDP \|\| tproto == IPPROTO_TCP) {
	276	hp = skb_header_pointer(skb, thoff,
	277	sizeof(_hdr), &_hdr);
	278	if (hp == NULL)
	279	return false;
	280
	281	saddr = &iph->saddr;
	282	sport = hp->source;
	283	daddr = &iph->daddr;
	284	dport = hp->dest;
	285
	286	} else if (tproto == IPPROTO_ICMPV6) {
	287	if (extract_icmp6_fields(skb, thoff, &tproto, &saddr, &daddr,
	288	&sport, &dport))
	289	return false;
	290	} else {
	291	return false;
	292	}
	293
	294	sk = nf_tproxy_get_sock_v6(dev_net(skb->dev), tproto,
	295	saddr, daddr, sport, dport, par->in, NFT_LOOKUP_ANY);
	296	if (sk != NULL) {
	297	bool wildcard;
	298	bool transparent = true;
	299
	300	/* Ignore sockets listening on INADDR_ANY */
	301	wildcard = (sk->sk_state != TCP_TIME_WAIT &&
	302	ipv6_addr_any(&inet6_sk(sk)->rcv_saddr));
	303
	304	/* Ignore non-transparent sockets,
	305	if XT_SOCKET_TRANSPARENT is used */
	306	if (info && info->flags & XT_SOCKET_TRANSPARENT)
	307	transparent = ((sk->sk_state != TCP_TIME_WAIT &&
	308	inet_sk(sk)->transparent) \|\|
	309	(sk->sk_state == TCP_TIME_WAIT &&
	310	inet_twsk(sk)->tw_transparent));
	311
d503b30b	312	xt_socket_put_sk(sk);
b64c9256 BS	313
	314	if (wildcard \|\| !transparent)
	315	sk = NULL;
	316	}
	317
089282fb	318	pr_debug("proto %hhd %pI6:%hu -> %pI6:%hu "
b64c9256 BS	319	"(orig %pI6:%hu) sock %p\n",
	320	tproto, saddr, ntohs(sport),
	321	daddr, ntohs(dport),
	322	&iph->daddr, hp ? ntohs(hp->dest) : 0, sk);
	323
	324	return (sk != NULL);
	325	}
	326	#endif
	327
a31e1ffd LAT	328	static struct xt_match socket_mt_reg[] __read_mostly = {
	329	{
	330	.name = "socket",
	331	.revision = 0,
	332	.family = NFPROTO_IPV4,
b64c9256	333	.match = socket_mt4_v0,
aa3c487f JE	334	.hooks = (1 << NF_INET_PRE_ROUTING) \|
aa3c487f JE	335	(1 << NF_INET_LOCAL_IN),
a31e1ffd LAT	336	.me = THIS_MODULE,
	337	},
	338	{
	339	.name = "socket",
	340	.revision = 1,
	341	.family = NFPROTO_IPV4,
b64c9256	342	.match = socket_mt4_v1,
a31e1ffd	343	.matchsize = sizeof(struct xt_socket_mtinfo1),
aa3c487f JE	344	.hooks = (1 << NF_INET_PRE_ROUTING) \|
aa3c487f JE	345	(1 << NF_INET_LOCAL_IN),
a31e1ffd LAT	346	.me = THIS_MODULE,
a31e1ffd LAT	347	},
f6318e55	348	#ifdef XT_SOCKET_HAVE_IPV6
b64c9256 BS	349	{
	350	.name = "socket",
	351	.revision = 1,
	352	.family = NFPROTO_IPV6,
	353	.match = socket_mt6_v1,
	354	.matchsize = sizeof(struct xt_socket_mtinfo1),
	355	.hooks = (1 << NF_INET_PRE_ROUTING) \|
	356	(1 << NF_INET_LOCAL_IN),
	357	.me = THIS_MODULE,
	358	},
	359	#endif
136cdc71 KK	360	};
	361
	362	static int __init socket_mt_init(void)
	363	{
	364	nf_defrag_ipv4_enable();
f6318e55	365	#ifdef XT_SOCKET_HAVE_IPV6
b64c9256 BS	366	nf_defrag_ipv6_enable();
	367	#endif
	368
a31e1ffd	369	return xt_register_matches(socket_mt_reg, ARRAY_SIZE(socket_mt_reg));
136cdc71 KK	370	}
	371
	372	static void __exit socket_mt_exit(void)
	373	{
a31e1ffd	374	xt_unregister_matches(socket_mt_reg, ARRAY_SIZE(socket_mt_reg));
136cdc71 KK	375	}
	376
	377	module_init(socket_mt_init);
	378	module_exit(socket_mt_exit);
	379
	380	MODULE_LICENSE("GPL");
	381	MODULE_AUTHOR("Krisztian Kovacs, Balazs Scheidler");
	382	MODULE_DESCRIPTION("x_tables socket match module");
	383	MODULE_ALIAS("ipt_socket");
b64c9256	384	MODULE_ALIAS("ip6t_socket");