netfilter: xt_socket: added new revision of the 'socket' match supporting flags

If the XT_SOCKET_TRANSPARENT flag is set, enabled 'transparent'
socket option is required for the socket to be matched.

Signed-off-by: Laszlo Attila Toth <panther@balabit.hu>
Signed-off-by: Patrick McHardy <kaber@trash.net>
This commit is contained in:
Laszlo Attila Toth 2009-06-09 15:16:34 +02:00 committed by Patrick McHardy
parent 11eeef41d5
commit a31e1ffd22
2 changed files with 64 additions and 11 deletions

View File

@ -0,0 +1,12 @@
#ifndef _XT_SOCKET_H
#define _XT_SOCKET_H
enum {
XT_SOCKET_TRANSPARENT = 1 << 0,
};
struct xt_socket_mtinfo1 {
__u8 flags;
};
#endif /* _XT_SOCKET_H */

View File

@ -22,6 +22,8 @@
#include <net/netfilter/nf_tproxy_core.h>
#include <net/netfilter/ipv4/nf_defrag_ipv4.h>
#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>
@ -86,7 +88,8 @@ extract_icmp_fields(const struct sk_buff *skb,
static bool
socket_mt(const struct sk_buff *skb, const struct xt_match_param *par)
socket_match(const struct sk_buff *skb, const struct xt_match_param *par,
const struct xt_socket_mtinfo1 *info)
{
const struct iphdr *iph = ip_hdr(skb);
struct udphdr _hdr, *hp = NULL;
@ -141,10 +144,24 @@ socket_mt(const struct sk_buff *skb, const struct xt_match_param *par)
sk = nf_tproxy_get_sock_v4(dev_net(skb->dev), protocol,
saddr, daddr, sport, dport, par->in, false);
if (sk != NULL) {
bool wildcard = (sk->sk_state != TCP_TIME_WAIT && inet_sk(sk)->rcv_saddr == 0);
bool wildcard;
bool transparent = true;
/* Ignore sockets listening on INADDR_ANY */
wildcard = (sk->sk_state != TCP_TIME_WAIT &&
inet_sk(sk)->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)
if (wildcard || !transparent)
sk = NULL;
}
@ -157,23 +174,47 @@ socket_mt(const struct sk_buff *skb, const struct xt_match_param *par)
return (sk != NULL);
}
static struct xt_match socket_mt_reg __read_mostly = {
.name = "socket",
.family = AF_INET,
.match = socket_mt,
.hooks = 1 << NF_INET_PRE_ROUTING,
.me = THIS_MODULE,
static bool
socket_mt_v0(const struct sk_buff *skb, const struct xt_match_param *par)
{
return socket_match(skb, par, NULL);
}
static bool
socket_mt_v1(const struct sk_buff *skb, const struct xt_match_param *par)
{
return socket_match(skb, par, par->matchinfo);
}
static struct xt_match socket_mt_reg[] __read_mostly = {
{
.name = "socket",
.revision = 0,
.family = NFPROTO_IPV4,
.match = socket_mt_v0,
.hooks = 1 << NF_INET_PRE_ROUTING,
.me = THIS_MODULE,
},
{
.name = "socket",
.revision = 1,
.family = NFPROTO_IPV4,
.match = socket_mt_v1,
.matchsize = sizeof(struct xt_socket_mtinfo1),
.hooks = 1 << NF_INET_PRE_ROUTING,
.me = THIS_MODULE,
},
};
static int __init socket_mt_init(void)
{
nf_defrag_ipv4_enable();
return xt_register_match(&socket_mt_reg);
return xt_register_matches(socket_mt_reg, ARRAY_SIZE(socket_mt_reg));
}
static void __exit socket_mt_exit(void)
{
xt_unregister_match(&socket_mt_reg);
xt_unregister_matches(socket_mt_reg, ARRAY_SIZE(socket_mt_reg));
}
module_init(socket_mt_init);