kernel: add a patch to allow disabling processing of the netfilter "filter" table for established connection packets

Signed-off-by: Felix Fietkau <nbd@openwrt.org>

SVN-Revision: 42046
This commit is contained in:
Felix Fietkau 2014-08-07 18:59:22 +00:00
parent 3e64341eac
commit 053a3a4aaf
2 changed files with 174 additions and 0 deletions

View File

@ -0,0 +1,87 @@
--- a/include/net/netns/conntrack.h
+++ b/include/net/netns/conntrack.h
@@ -80,6 +80,7 @@ struct netns_ct {
int sysctl_acct;
int sysctl_tstamp;
int sysctl_checksum;
+ int skip_filter;
unsigned int sysctl_log_invalid; /* Log invalid packets */
int sysctl_auto_assign_helper;
bool auto_assign_helper_warned;
--- a/net/ipv4/netfilter/iptable_filter.c
+++ b/net/ipv4/netfilter/iptable_filter.c
@@ -15,6 +15,7 @@
#include <linux/netfilter_ipv4/ip_tables.h>
#include <linux/slab.h>
#include <net/ip.h>
+#include <net/netfilter/nf_conntrack.h>
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Netfilter Core Team <coreteam@netfilter.org>");
@@ -37,6 +38,7 @@ iptable_filter_hook(unsigned int hook, s
const struct net_device *in, const struct net_device *out,
int (*okfn)(struct sk_buff *))
{
+ enum ip_conntrack_info ctinfo;
const struct net *net;
if (hook == NF_INET_LOCAL_OUT &&
@@ -46,6 +48,11 @@ iptable_filter_hook(unsigned int hook, s
return NF_ACCEPT;
net = dev_net((in != NULL) ? in : out);
+ nf_ct_get(skb, &ctinfo);
+ if ((ctinfo == IP_CT_ESTABLISHED_REPLY || ctinfo == IP_CT_ESTABLISHED) &&
+ net->ct.skip_filter)
+ return NF_ACCEPT;
+
return ipt_do_table(skb, hook, in, out, net->ipv4.iptable_filter);
}
--- a/net/ipv6/netfilter/ip6table_filter.c
+++ b/net/ipv6/netfilter/ip6table_filter.c
@@ -13,6 +13,7 @@
#include <linux/moduleparam.h>
#include <linux/netfilter_ipv6/ip6_tables.h>
#include <linux/slab.h>
+#include <net/netfilter/nf_conntrack.h>
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Netfilter Core Team <coreteam@netfilter.org>");
@@ -37,6 +38,12 @@ ip6table_filter_hook(unsigned int hook,
int (*okfn)(struct sk_buff *))
{
const struct net *net = dev_net((in != NULL) ? in : out);
+ enum ip_conntrack_info ctinfo;
+
+ nf_ct_get(skb, &ctinfo);
+ if ((ctinfo == IP_CT_ESTABLISHED_REPLY || ctinfo == IP_CT_ESTABLISHED) &&
+ net->ct.skip_filter)
+ return NF_ACCEPT;
return ip6t_do_table(skb, hook, in, out, net->ipv6.ip6table_filter);
}
--- a/net/netfilter/nf_conntrack_standalone.c
+++ b/net/netfilter/nf_conntrack_standalone.c
@@ -477,6 +477,13 @@ static ctl_table nf_ct_sysctl_table[] =
.extra2 = &log_invalid_proto_max,
},
{
+ .procname = "nf_conntrack_skip_filter",
+ .data = &init_net.ct.skip_filter,
+ .maxlen = sizeof(int),
+ .mode = 0644,
+ .proc_handler = proc_dointvec,
+ },
+ {
.procname = "nf_conntrack_expect_max",
.data = &nf_ct_expect_max,
.maxlen = sizeof(int),
@@ -512,6 +519,7 @@ static int nf_conntrack_standalone_init_
table[2].data = &net->ct.htable_size;
table[3].data = &net->ct.sysctl_checksum;
table[4].data = &net->ct.sysctl_log_invalid;
+ table[5].data = &net->ct.skip_filter;
/* Don't export sysctls to unprivileged users */
if (net->user_ns != &init_user_ns)

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@ -0,0 +1,87 @@
--- a/include/net/netns/conntrack.h
+++ b/include/net/netns/conntrack.h
@@ -73,6 +73,7 @@ struct netns_ct {
struct ctl_table_header *helper_sysctl_header;
#endif
char *slabname;
+ int skip_filter;
unsigned int sysctl_log_invalid; /* Log invalid packets */
unsigned int sysctl_events_retry_timeout;
int sysctl_events;
--- a/net/ipv4/netfilter/iptable_filter.c
+++ b/net/ipv4/netfilter/iptable_filter.c
@@ -15,6 +15,7 @@
#include <linux/netfilter_ipv4/ip_tables.h>
#include <linux/slab.h>
#include <net/ip.h>
+#include <net/netfilter/nf_conntrack.h>
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Netfilter Core Team <coreteam@netfilter.org>");
@@ -37,6 +38,7 @@ iptable_filter_hook(const struct nf_hook
const struct net_device *in, const struct net_device *out,
int (*okfn)(struct sk_buff *))
{
+ enum ip_conntrack_info ctinfo;
const struct net *net;
if (ops->hooknum == NF_INET_LOCAL_OUT &&
@@ -46,6 +48,11 @@ iptable_filter_hook(const struct nf_hook
return NF_ACCEPT;
net = dev_net((in != NULL) ? in : out);
+ nf_ct_get(skb, &ctinfo);
+ if ((ctinfo == IP_CT_ESTABLISHED_REPLY || ctinfo == IP_CT_ESTABLISHED) &&
+ net->ct.skip_filter)
+ return NF_ACCEPT;
+
return ipt_do_table(skb, ops->hooknum, in, out,
net->ipv4.iptable_filter);
}
--- a/net/ipv6/netfilter/ip6table_filter.c
+++ b/net/ipv6/netfilter/ip6table_filter.c
@@ -13,6 +13,7 @@
#include <linux/moduleparam.h>
#include <linux/netfilter_ipv6/ip6_tables.h>
#include <linux/slab.h>
+#include <net/netfilter/nf_conntrack.h>
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Netfilter Core Team <coreteam@netfilter.org>");
@@ -37,6 +38,12 @@ ip6table_filter_hook(const struct nf_hoo
int (*okfn)(struct sk_buff *))
{
const struct net *net = dev_net((in != NULL) ? in : out);
+ enum ip_conntrack_info ctinfo;
+
+ nf_ct_get(skb, &ctinfo);
+ if ((ctinfo == IP_CT_ESTABLISHED_REPLY || ctinfo == IP_CT_ESTABLISHED) &&
+ net->ct.skip_filter)
+ return NF_ACCEPT;
return ip6t_do_table(skb, ops->hooknum, in, out,
net->ipv6.ip6table_filter);
--- a/net/netfilter/nf_conntrack_standalone.c
+++ b/net/netfilter/nf_conntrack_standalone.c
@@ -477,6 +477,13 @@ static struct ctl_table nf_ct_sysctl_tab
.extra2 = &log_invalid_proto_max,
},
{
+ .procname = "nf_conntrack_skip_filter",
+ .data = &init_net.ct.skip_filter,
+ .maxlen = sizeof(int),
+ .mode = 0644,
+ .proc_handler = proc_dointvec,
+ },
+ {
.procname = "nf_conntrack_expect_max",
.data = &nf_ct_expect_max,
.maxlen = sizeof(int),
@@ -512,6 +519,7 @@ static int nf_conntrack_standalone_init_
table[2].data = &net->ct.htable_size;
table[3].data = &net->ct.sysctl_checksum;
table[4].data = &net->ct.sysctl_log_invalid;
+ table[5].data = &net->ct.skip_filter;
/* Don't export sysctls to unprivileged users */
if (net->user_ns != &init_user_ns)