new file mode 100644
@@ -0,0 +1,282 @@
+/*
+ * 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.
+ */
+
+#include <linux/skbuff.h>
+
+#include <net/tcp.h>
+#include <net/udp.h>
+#include <net/icmp.h>
+#include <net/sock.h>
+
+#include <net/netfilter/ipv4/nf_defrag_ipv4.h>
+
+#if IS_ENABLED(CONFIG_IP6_NF_IPTABLES)
+#define XT_HAVE_IPV6 1
+#include <linux/netfilter_ipv6/ip6_tables.h>
+#include <net/inet6_hashtables.h>
+#include <net/netfilter/ipv6/nf_defrag_ipv6.h>
+#endif
+
+#if IS_ENABLED(CONFIG_NF_CONNTRACK)
+#define XT_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 struct sock *xt_get_sk_v4(struct net *net, const u8 protocol,
+ const __be32 saddr, const __be32 daddr,
+ const __be16 sport, const __be16 dport,
+ const struct net_device *in)
+{
+ switch (protocol) {
+ case IPPROTO_TCP:
+ return __inet_lookup(net, &tcp_hashinfo,
+ saddr, sport, daddr, dport,
+ in->ifindex);
+ case IPPROTO_UDP:
+ return udp4_lib_lookup(net, saddr, sport, daddr, dport,
+ in->ifindex);
+ }
+
+ return NULL;
+}
+
+static struct sock *xt_sk_lookup(const struct sk_buff *skb,
+ const struct net_device *indev)
+{
+ const struct iphdr *iph = ip_hdr(skb);
+ __be32 uninitialized_var(daddr), uninitialized_var(saddr);
+ __be16 uninitialized_var(dport), uninitialized_var(sport);
+ u8 uninitialized_var(protocol);
+#ifdef XT_HAVE_CONNTRACK
+ struct nf_conn const *ct;
+ enum ip_conntrack_info ctinfo;
+#endif
+
+ if (iph->protocol == IPPROTO_UDP || iph->protocol == IPPROTO_TCP) {
+ struct udphdr _hdr, *hp = NULL;
+
+ hp = skb_header_pointer(skb, ip_hdrlen(skb),
+ sizeof(_hdr), &_hdr);
+ if (hp == NULL)
+ return NULL;
+
+ protocol = iph->protocol;
+
+ saddr = iph->saddr;
+ daddr = iph->daddr;
+
+ sport = hp->source;
+ 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_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
+ return xt_get_sk_v4(dev_net(skb->dev), protocol, saddr, daddr,
+ sport, dport, indev);
+}
+
+#ifdef XT_HAVE_IPV6
+static int extract_icmp6_fields(const struct sk_buff *skb,
+ unsigned int outside_hdrlen,
+ int *protocol,
+ const struct in6_addr **raddr,
+ const struct in6_addr **laddr,
+ __be16 *rport, __be16 *lport,
+ struct ipv6hdr *ipv6_var)
+{
+ const struct ipv6hdr *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(*ipv6_var), ipv6_var);
+ if (inside_iph == NULL)
+ return 1;
+
+ inside_nexthdr = inside_iph->nexthdr;
+ inside_hdrlen = ipv6_skip_exthdr(skb, outside_hdrlen + sizeof(_icmph) +
+ sizeof(*ipv6_var),
+ &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 struct sock *xt_get_sk_v6(struct net *net, const u8 protocol,
+ const struct in6_addr *saddr,
+ const struct in6_addr *daddr,
+ const __be16 sport, const __be16 dport,
+ const struct net_device *in)
+{
+ switch (protocol) {
+ case IPPROTO_TCP:
+ return inet6_lookup(net, &tcp_hashinfo,
+ saddr, sport, daddr, dport,
+ in->ifindex);
+ case IPPROTO_UDP:
+ return udp6_lib_lookup(net, saddr, sport, daddr, dport,
+ in->ifindex);
+ }
+
+ return NULL;
+}
+
+static struct sock *xt_sk_lookup6(const struct sk_buff *skb,
+ const struct net_device *indev)
+{
+ __be16 uninitialized_var(dport), uninitialized_var(sport);
+ const struct in6_addr *daddr = NULL, *saddr = NULL;
+ struct ipv6hdr *iph = ipv6_hdr(skb);
+ int thoff = 0, 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 NULL;
+ }
+
+ if (tproto == IPPROTO_UDP || tproto == IPPROTO_TCP) {
+ struct udphdr _hdr, *hp;
+
+ hp = skb_header_pointer(skb, thoff, sizeof(_hdr), &_hdr);
+ if (hp == NULL)
+ return NULL;
+
+ saddr = &iph->saddr;
+ daddr = &iph->daddr;
+
+ sport = hp->source;
+ dport = hp->dest;
+
+ } else if (tproto == IPPROTO_ICMPV6) {
+ struct ipv6hdr ipv6_var;
+
+ if (extract_icmp6_fields(skb, thoff, &tproto, &saddr, &daddr,
+ &sport, &dport, &ipv6_var))
+ return NULL;
+ } else {
+ return NULL;
+ }
+
+ return xt_get_sk_v6(dev_net(skb->dev), tproto, saddr, daddr,
+ sport, dport, indev);
+}
+#endif /* XT_HAVE_IPV6 */
@@ -7,90 +7,18 @@
* 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/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/inet6_hashtables.h>
-#include <net/netfilter/ipv6/nf_defrag_ipv6.h>
-#endif
+#include <linux/netfilter/x_tables.h>
#include <linux/netfilter/xt_socket.h>
+#include <linux/netfilter_ipv4/ip_tables.h>
-#if IS_ENABLED(CONFIG_NF_CONNTRACK)
-#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;
-}
+#include "xt_sk_helper.h"
/* "socket" match based redirection (no specific rule)
* ===================================================
@@ -111,23 +39,6 @@ extract_icmp4_fields(const struct sk_buff *skb,
* then local services could intercept traffic going through the
* box.
*/
-static struct sock *
-xt_socket_get_sock_v4(struct net *net, const u8 protocol,
- const __be32 saddr, const __be32 daddr,
- const __be16 sport, const __be16 dport,
- const struct net_device *in)
-{
- switch (protocol) {
- case IPPROTO_TCP:
- return __inet_lookup(net, &tcp_hashinfo,
- saddr, sport, daddr, dport,
- in->ifindex);
- case IPPROTO_UDP:
- return udp4_lib_lookup(net, saddr, sport, daddr, dport,
- in->ifindex);
- }
- return NULL;
-}
static bool xt_socket_sk_is_transparent(struct sock *sk)
{
@@ -147,63 +58,13 @@ 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 = skb->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
if (!sk)
- sk = xt_socket_get_sock_v4(dev_net(skb->dev), protocol,
- saddr, daddr, sport, dport,
- par->in);
+ sk = xt_sk_lookup(skb, par->in);
if (sk) {
- bool wildcard;
bool transparent = true;
+ bool wildcard;
/* Ignore sockets listening on INADDR_ANY,
* unless XT_SOCKET_NOWILDCARD is set
@@ -225,12 +86,7 @@ socket_match(const struct sk_buff *skb, struct xt_action_param *par,
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);
+ return sk != NULL;
}
static bool
@@ -249,127 +105,18 @@ socket_mt4_v1_v2(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,
- const struct in6_addr **raddr,
- const struct in6_addr **laddr,
- __be16 *rport,
- __be16 *lport,
- struct ipv6hdr *ipv6_var)
-{
- const struct ipv6hdr *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(*ipv6_var), ipv6_var);
- if (inside_iph == NULL)
- return 1;
- inside_nexthdr = inside_iph->nexthdr;
-
- inside_hdrlen = ipv6_skip_exthdr(skb, outside_hdrlen + sizeof(_icmph) +
- sizeof(*ipv6_var),
- &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 struct sock *
-xt_socket_get_sock_v6(struct net *net, const u8 protocol,
- const struct in6_addr *saddr, const struct in6_addr *daddr,
- const __be16 sport, const __be16 dport,
- const struct net_device *in)
-{
- switch (protocol) {
- case IPPROTO_TCP:
- return inet6_lookup(net, &tcp_hashinfo,
- saddr, sport, daddr, dport,
- in->ifindex);
- case IPPROTO_UDP:
- return udp6_lib_lookup(net, saddr, sport, daddr, dport,
- in->ifindex);
- }
-
- return NULL;
-}
-
+#ifdef XT_HAVE_IPV6
static bool
socket_mt6_v1_v2(const struct sk_buff *skb, struct xt_action_param *par)
{
- struct ipv6hdr ipv6_var, *iph = ipv6_hdr(skb);
- struct udphdr _hdr, *hp = NULL;
- struct sock *sk = skb->sk;
- const 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, &ipv6_var))
- return false;
- } else {
- return false;
- }
+ struct sock *sk = skb->sk;
if (!sk)
- sk = xt_socket_get_sock_v6(dev_net(skb->dev), tproto,
- saddr, daddr, sport, dport,
- par->in);
+ sk = xt_sk_lookup6(skb, par->in);
if (sk) {
- bool wildcard;
bool transparent = true;
+ bool wildcard;
/* Ignore sockets listening on INADDR_ANY
* unless XT_SOCKET_NOWILDCARD is set
@@ -391,13 +138,7 @@ socket_mt6_v1_v2(const struct sk_buff *skb, struct xt_action_param *par)
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);
+ return sk != NULL;
}
#endif
@@ -409,6 +150,7 @@ static int socket_mt_v1_check(const struct xt_mtchk_param *par)
pr_info("unknown flags 0x%x\n", info->flags & ~XT_SOCKET_FLAGS_V1);
return -EINVAL;
}
+
return 0;
}
@@ -420,6 +162,7 @@ static int socket_mt_v2_check(const struct xt_mtchk_param *par)
pr_info("unknown flags 0x%x\n", info->flags & ~XT_SOCKET_FLAGS_V2);
return -EINVAL;
}
+
return 0;
}
@@ -444,7 +187,7 @@ static struct xt_match socket_mt_reg[] __read_mostly = {
(1 << NF_INET_LOCAL_IN),
.me = THIS_MODULE,
},
-#ifdef XT_SOCKET_HAVE_IPV6
+#ifdef XT_HAVE_IPV6
{
.name = "socket",
.revision = 1,
@@ -468,7 +211,7 @@ static struct xt_match socket_mt_reg[] __read_mostly = {
(1 << NF_INET_LOCAL_IN),
.me = THIS_MODULE,
},
-#ifdef XT_SOCKET_HAVE_IPV6
+#ifdef XT_HAVE_IPV6
{
.name = "socket",
.revision = 2,
@@ -486,7 +229,7 @@ static struct xt_match socket_mt_reg[] __read_mostly = {
static int __init socket_mt_init(void)
{
nf_defrag_ipv4_enable();
-#ifdef XT_SOCKET_HAVE_IPV6
+#ifdef XT_HAVE_IPV6
nf_defrag_ipv6_enable();
#endif
The socket lookup helpers are also needed for fixing xt_cgroups, therefore refactor them into shareable helper functions. This simplifies and optimizes the xt_socket code itself a bit as well, i.e. time to verdict for early demux sockets should be much faster than previously: We've unnecessarily extracted proto, {s,d}addr and {s,d}ports from the skb data, accessing possible conntrack information, etc even though we were not even calling into the socket lookup via xt_socket_get_sock_v4() due to skb->sk hit. After this patch, we only proceed the slow-path when we have a skb->sk miss. Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Cc: Daniel Mack <daniel@zonque.org> Cc: Florian Westphal <fw@strlen.de> --- net/netfilter/xt_sk_helper.h | 282 +++++++++++++++++++++++++++++++++++++++++ net/netfilter/xt_socket.c | 293 +++---------------------------------------- 2 files changed, 300 insertions(+), 275 deletions(-) create mode 100644 net/netfilter/xt_sk_helper.h