[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

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);
}
EXPORT_SYMBOL(xt_socket_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;
}

struct sock*
xt_socket_get4_sk(const struct sk_buff *skb, struct xt_action_param *par)
{
	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 NULL;

		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 NULL;
	} else {
		return NULL;
	}

#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);

	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;
}
EXPORT_SYMBOL(xt_socket_get4_sk);

static bool
socket_match(const struct sk_buff *skb, struct xt_action_param *par,
	     const struct xt_socket_mtinfo1 *info)
{
	struct sock *sk;

	sk = xt_socket_get4_sk(skb, par);
	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;
	}

	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;
}

struct sock*
xt_socket_get6_sk(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);

	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 NULL;

		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 NULL;
	} else {
		return NULL;
	}

	sk = nf_tproxy_get_sock_v6(dev_net(skb->dev), tproto,
				   saddr, daddr, sport, dport, par->in, NFT_LOOKUP_ANY);
	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;
}
EXPORT_SYMBOL(xt_socket_get6_sk);

static bool
socket_mt6_v1(const struct sk_buff *skb, struct xt_action_param *par)
{
	struct sock *sk;
	const struct xt_socket_mtinfo1 *info;

	info = (struct xt_socket_mtinfo1 *) par->matchinfo;
	sk = xt_socket_get6_sk(skb, par);
	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;
	}

	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
6fa3eb70	38	void
d503b30b FW	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	}
6fa3eb70	46	EXPORT_SYMBOL(xt_socket_put_sk);
d503b30b	47
136cdc71	48	static int
b64c9256	49	extract_icmp4_fields(const struct sk_buff *skb,
136cdc71 KK	50	u8 *protocol,
	51	__be32 *raddr,
	52	__be32 *laddr,
	53	__be16 *rport,
	54	__be16 *lport)
	55	{
	56	unsigned int outside_hdrlen = ip_hdrlen(skb);
	57	struct iphdr *inside_iph, _inside_iph;
	58	struct icmphdr *icmph, _icmph;
	59	__be16 *ports, _ports[2];
	60
	61	icmph = skb_header_pointer(skb, outside_hdrlen,
	62	sizeof(_icmph), &_icmph);
	63	if (icmph == NULL)
	64	return 1;
	65
	66	switch (icmph->type) {
	67	case ICMP_DEST_UNREACH:
	68	case ICMP_SOURCE_QUENCH:
	69	case ICMP_REDIRECT:
	70	case ICMP_TIME_EXCEEDED:
	71	case ICMP_PARAMETERPROB:
	72	break;
	73	default:
	74	return 1;
	75	}
	76
	77	inside_iph = skb_header_pointer(skb, outside_hdrlen +
	78	sizeof(struct icmphdr),
	79	sizeof(_inside_iph), &_inside_iph);
	80	if (inside_iph == NULL)
	81	return 1;
	82
	83	if (inside_iph->protocol != IPPROTO_TCP &&
	84	inside_iph->protocol != IPPROTO_UDP)
	85	return 1;
	86
	87	ports = skb_header_pointer(skb, outside_hdrlen +
	88	sizeof(struct icmphdr) +
	89	(inside_iph->ihl << 2),
	90	sizeof(_ports), &_ports);
	91	if (ports == NULL)
	92	return 1;
	93
	94	/* the inside IP packet is the one quoted from our side, thus
	95	* its saddr is the local address */
	96	*protocol = inside_iph->protocol;
	97	*laddr = inside_iph->saddr;
	98	*lport = ports[0];
	99	*raddr = inside_iph->daddr;
	100	*rport = ports[1];
	101
	102	return 0;
	103	}
	104
6fa3eb70 S	105	struct sock*
6fa3eb70 S	106	xt_socket_get4_sk(const struct sk_buff skb, struct xt_action_param par)
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)
6fa3eb70	123	return NULL;
136cdc71 KK	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	133	&sport, &dport))
6fa3eb70	134	return NULL;
136cdc71	135	} else {
6fa3eb70	136	return NULL;
136cdc71 KK	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);
6fa3eb70 S	160
	161	pr_debug("proto %hhu %pI4:%hu -> %pI4:%hu (orig %pI4:%hu) sock %p\n",
	162	protocol, &saddr, ntohs(sport),
	163	&daddr, ntohs(dport),
	164	&iph->daddr, hp ? ntohs(hp->dest) : 0, sk);
	165
	166	return sk;
	167	}
	168	EXPORT_SYMBOL(xt_socket_get4_sk);
	169
	170	static bool
	171	socket_match(const struct sk_buff skb, struct xt_action_param par,
	172	const struct xt_socket_mtinfo1 *info)
	173	{
	174	struct sock *sk;
	175
	176	sk = xt_socket_get4_sk(skb, par);
136cdc71	177	if (sk != NULL) {
a31e1ffd LAT	178	bool wildcard;
	179	bool transparent = true;
	180
	181	/* Ignore sockets listening on INADDR_ANY */
	182	wildcard = (sk->sk_state != TCP_TIME_WAIT &&
c720c7e8	183	inet_sk(sk)->inet_rcv_saddr == 0);
a31e1ffd LAT	184
	185	/* Ignore non-transparent sockets,
	186	if XT_SOCKET_TRANSPARENT is used */
	187	if (info && info->flags & XT_SOCKET_TRANSPARENT)
	188	transparent = ((sk->sk_state != TCP_TIME_WAIT &&
	189	inet_sk(sk)->transparent) \|\|
	190	(sk->sk_state == TCP_TIME_WAIT &&
	191	inet_twsk(sk)->tw_transparent));
136cdc71	192
d503b30b	193	xt_socket_put_sk(sk);
a31e1ffd LAT	194
a31e1ffd LAT	195	if (wildcard \|\| !transparent)
136cdc71 KK	196	sk = NULL;
	197	}
	198
136cdc71 KK	199	return (sk != NULL);
	200	}
	201
a31e1ffd	202	static bool
b64c9256	203	socket_mt4_v0(const struct sk_buff skb, struct xt_action_param par)
a31e1ffd LAT	204	{
	205	return socket_match(skb, par, NULL);
	206	}
	207
	208	static bool
b64c9256	209	socket_mt4_v1(const struct sk_buff skb, struct xt_action_param par)
a31e1ffd LAT	210	{
	211	return socket_match(skb, par, par->matchinfo);
	212	}
	213
f6318e55	214	#ifdef XT_SOCKET_HAVE_IPV6
b64c9256 BS	215
	216	static int
	217	extract_icmp6_fields(const struct sk_buff *skb,
	218	unsigned int outside_hdrlen,
089282fb	219	int *protocol,
b64c9256 BS	220	struct in6_addr **raddr,
	221	struct in6_addr **laddr,
	222	__be16 *rport,
	223	__be16 *lport)
	224	{
	225	struct ipv6hdr *inside_iph, _inside_iph;
	226	struct icmp6hdr *icmph, _icmph;
	227	__be16 *ports, _ports[2];
	228	u8 inside_nexthdr;
75f2811c	229	__be16 inside_fragoff;
b64c9256 BS	230	int inside_hdrlen;
	231
	232	icmph = skb_header_pointer(skb, outside_hdrlen,
	233	sizeof(_icmph), &_icmph);
	234	if (icmph == NULL)
	235	return 1;
	236
	237	if (icmph->icmp6_type & ICMPV6_INFOMSG_MASK)
	238	return 1;
	239
	240	inside_iph = skb_header_pointer(skb, outside_hdrlen + sizeof(_icmph), sizeof(_inside_iph), &_inside_iph);
	241	if (inside_iph == NULL)
	242	return 1;
	243	inside_nexthdr = inside_iph->nexthdr;
	244
75f2811c JG	245	inside_hdrlen = ipv6_skip_exthdr(skb, outside_hdrlen + sizeof(_icmph) + sizeof(_inside_iph),
75f2811c JG	246	&inside_nexthdr, &inside_fragoff);
b64c9256 BS	247	if (inside_hdrlen < 0)
	248	return 1; /* hjm: Packet has no/incomplete transport layer headers. */
	249
	250	if (inside_nexthdr != IPPROTO_TCP &&
	251	inside_nexthdr != IPPROTO_UDP)
	252	return 1;
	253
	254	ports = skb_header_pointer(skb, inside_hdrlen,
	255	sizeof(_ports), &_ports);
	256	if (ports == NULL)
	257	return 1;
	258
	259	/* the inside IP packet is the one quoted from our side, thus
	260	* its saddr is the local address */
	261	*protocol = inside_nexthdr;
	262	*laddr = &inside_iph->saddr;
	263	*lport = ports[0];
	264	*raddr = &inside_iph->daddr;
	265	*rport = ports[1];
	266
	267	return 0;
	268	}
	269
6fa3eb70 S	270	struct sock*
6fa3eb70 S	271	xt_socket_get6_sk(const struct sk_buff skb, struct xt_action_param par)
b64c9256 BS	272	{
	273	struct ipv6hdr *iph = ipv6_hdr(skb);
	274	struct udphdr _hdr, *hp = NULL;
	275	struct sock *sk;
6703aa74 PNA	276	struct in6_addr daddr = NULL, saddr = NULL;
	277	__be16 uninitialized_var(dport), uninitialized_var(sport);
	278	int thoff = 0, uninitialized_var(tproto);
b64c9256	279
84018f55	280	tproto = ipv6_find_hdr(skb, &thoff, -1, NULL, NULL);
b64c9256 BS	281	if (tproto < 0) {
	282	pr_debug("unable to find transport header in IPv6 packet, dropping\n");
	283	return NF_DROP;
	284	}
	285
	286	if (tproto == IPPROTO_UDP \|\| tproto == IPPROTO_TCP) {
	287	hp = skb_header_pointer(skb, thoff,
	288	sizeof(_hdr), &_hdr);
	289	if (hp == NULL)
6fa3eb70	290	return NULL;
b64c9256 BS	291
	292	saddr = &iph->saddr;
	293	sport = hp->source;
	294	daddr = &iph->daddr;
	295	dport = hp->dest;
	296
	297	} else if (tproto == IPPROTO_ICMPV6) {
	298	if (extract_icmp6_fields(skb, thoff, &tproto, &saddr, &daddr,
	299	&sport, &dport))
6fa3eb70	300	return NULL;
b64c9256	301	} else {
6fa3eb70	302	return NULL;
b64c9256 BS	303	}
	304
	305	sk = nf_tproxy_get_sock_v6(dev_net(skb->dev), tproto,
	306	saddr, daddr, sport, dport, par->in, NFT_LOOKUP_ANY);
6fa3eb70 S	307	pr_debug("proto %hhd %pI6:%hu -> %pI6:%hu "
	308	"(orig %pI6:%hu) sock %p\n",
	309	tproto, saddr, ntohs(sport),
	310	daddr, ntohs(dport),
	311	&iph->daddr, hp ? ntohs(hp->dest) : 0, sk);
	312	return sk;
	313	}
	314	EXPORT_SYMBOL(xt_socket_get6_sk);
	315
	316	static bool
	317	socket_mt6_v1(const struct sk_buff skb, struct xt_action_param par)
	318	{
	319	struct sock *sk;
	320	const struct xt_socket_mtinfo1 *info;
	321
	322	info = (struct xt_socket_mtinfo1 *) par->matchinfo;
	323	sk = xt_socket_get6_sk(skb, par);
b64c9256 BS	324	if (sk != NULL) {
	325	bool wildcard;
	326	bool transparent = true;
	327
	328	/* Ignore sockets listening on INADDR_ANY */
	329	wildcard = (sk->sk_state != TCP_TIME_WAIT &&
	330	ipv6_addr_any(&inet6_sk(sk)->rcv_saddr));
	331
	332	/* Ignore non-transparent sockets,
	333	if XT_SOCKET_TRANSPARENT is used */
	334	if (info && info->flags & XT_SOCKET_TRANSPARENT)
	335	transparent = ((sk->sk_state != TCP_TIME_WAIT &&
	336	inet_sk(sk)->transparent) \|\|
	337	(sk->sk_state == TCP_TIME_WAIT &&
	338	inet_twsk(sk)->tw_transparent));
	339
d503b30b	340	xt_socket_put_sk(sk);
b64c9256 BS	341
	342	if (wildcard \|\| !transparent)
	343	sk = NULL;
	344	}
	345
b64c9256 BS	346	return (sk != NULL);
	347	}
	348	#endif
	349
a31e1ffd LAT	350	static struct xt_match socket_mt_reg[] __read_mostly = {
	351	{
	352	.name = "socket",
	353	.revision = 0,
	354	.family = NFPROTO_IPV4,
b64c9256	355	.match = socket_mt4_v0,
aa3c487f JE	356	.hooks = (1 << NF_INET_PRE_ROUTING) \|
aa3c487f JE	357	(1 << NF_INET_LOCAL_IN),
a31e1ffd LAT	358	.me = THIS_MODULE,
	359	},
	360	{
	361	.name = "socket",
	362	.revision = 1,
	363	.family = NFPROTO_IPV4,
b64c9256	364	.match = socket_mt4_v1,
a31e1ffd	365	.matchsize = sizeof(struct xt_socket_mtinfo1),
aa3c487f JE	366	.hooks = (1 << NF_INET_PRE_ROUTING) \|
aa3c487f JE	367	(1 << NF_INET_LOCAL_IN),
a31e1ffd LAT	368	.me = THIS_MODULE,
a31e1ffd LAT	369	},
f6318e55	370	#ifdef XT_SOCKET_HAVE_IPV6
b64c9256 BS	371	{
	372	.name = "socket",
	373	.revision = 1,
	374	.family = NFPROTO_IPV6,
	375	.match = socket_mt6_v1,
	376	.matchsize = sizeof(struct xt_socket_mtinfo1),
	377	.hooks = (1 << NF_INET_PRE_ROUTING) \|
	378	(1 << NF_INET_LOCAL_IN),
	379	.me = THIS_MODULE,
	380	},
	381	#endif
136cdc71 KK	382	};
	383
	384	static int __init socket_mt_init(void)
	385	{
	386	nf_defrag_ipv4_enable();
f6318e55	387	#ifdef XT_SOCKET_HAVE_IPV6
b64c9256 BS	388	nf_defrag_ipv6_enable();
	389	#endif
	390
a31e1ffd	391	return xt_register_matches(socket_mt_reg, ARRAY_SIZE(socket_mt_reg));
136cdc71 KK	392	}
	393
	394	static void __exit socket_mt_exit(void)
	395	{
a31e1ffd	396	xt_unregister_matches(socket_mt_reg, ARRAY_SIZE(socket_mt_reg));
136cdc71 KK	397	}
	398
	399	module_init(socket_mt_init);
	400	module_exit(socket_mt_exit);
	401
	402	MODULE_LICENSE("GPL");
	403	MODULE_AUTHOR("Krisztian Kovacs, Balazs Scheidler");
	404	MODULE_DESCRIPTION("x_tables socket match module");
	405	MODULE_ALIAS("ipt_socket");
b64c9256	406	MODULE_ALIAS("ip6t_socket");