netfilter: split netfilter IPv4 defragmentation into a separate module
Netfilter connection tracking requires all IPv4 packets to be defragmented.
Both the socket match and the TPROXY target depend on this functionality, so
this patch separates the Netfilter IPv4 defrag hooks into a separate module.
Signed-off-by: KOVACS Krisztian <hidden@sch.bme.hu>
Signed-off-by: Patrick McHardy <kaber@trash.net>
diff --git a/net/ipv4/netfilter/nf_conntrack_l3proto_ipv4.c b/net/ipv4/netfilter/nf_conntrack_l3proto_ipv4.c
index af69acc..4a7c352 100644
--- a/net/ipv4/netfilter/nf_conntrack_l3proto_ipv4.c
+++ b/net/ipv4/netfilter/nf_conntrack_l3proto_ipv4.c
@@ -1,3 +1,4 @@
+
/* (C) 1999-2001 Paul `Rusty' Russell
* (C) 2002-2004 Netfilter Core Team <coreteam@netfilter.org>
*
@@ -24,6 +25,7 @@
#include <net/netfilter/nf_conntrack_core.h>
#include <net/netfilter/ipv4/nf_conntrack_ipv4.h>
#include <net/netfilter/nf_nat_helper.h>
+#include <net/netfilter/ipv4/nf_defrag_ipv4.h>
int (*nf_nat_seq_adjust_hook)(struct sk_buff *skb,
struct nf_conn *ct,
@@ -63,23 +65,6 @@
NIPQUAD(tuple->dst.u3.ip));
}
-/* Returns new sk_buff, or NULL */
-static int nf_ct_ipv4_gather_frags(struct sk_buff *skb, u_int32_t user)
-{
- int err;
-
- skb_orphan(skb);
-
- local_bh_disable();
- err = ip_defrag(skb, user);
- local_bh_enable();
-
- if (!err)
- ip_send_check(ip_hdr(skb));
-
- return err;
-}
-
static int ipv4_get_l4proto(const struct sk_buff *skb, unsigned int nhoff,
unsigned int *dataoff, u_int8_t *protonum)
{
@@ -144,28 +129,6 @@
return nf_conntrack_confirm(skb);
}
-static unsigned int ipv4_conntrack_defrag(unsigned int hooknum,
- struct sk_buff *skb,
- const struct net_device *in,
- const struct net_device *out,
- int (*okfn)(struct sk_buff *))
-{
- /* Previously seen (loopback)? Ignore. Do this before
- fragment check. */
- if (skb->nfct)
- return NF_ACCEPT;
-
- /* Gather fragments. */
- if (ip_hdr(skb)->frag_off & htons(IP_MF | IP_OFFSET)) {
- if (nf_ct_ipv4_gather_frags(skb,
- hooknum == NF_INET_PRE_ROUTING ?
- IP_DEFRAG_CONNTRACK_IN :
- IP_DEFRAG_CONNTRACK_OUT))
- return NF_STOLEN;
- }
- return NF_ACCEPT;
-}
-
static unsigned int ipv4_conntrack_in(unsigned int hooknum,
struct sk_buff *skb,
const struct net_device *in,
@@ -195,13 +158,6 @@
make it the first hook. */
static struct nf_hook_ops ipv4_conntrack_ops[] __read_mostly = {
{
- .hook = ipv4_conntrack_defrag,
- .owner = THIS_MODULE,
- .pf = PF_INET,
- .hooknum = NF_INET_PRE_ROUTING,
- .priority = NF_IP_PRI_CONNTRACK_DEFRAG,
- },
- {
.hook = ipv4_conntrack_in,
.owner = THIS_MODULE,
.pf = PF_INET,
@@ -209,13 +165,6 @@
.priority = NF_IP_PRI_CONNTRACK,
},
{
- .hook = ipv4_conntrack_defrag,
- .owner = THIS_MODULE,
- .pf = PF_INET,
- .hooknum = NF_INET_LOCAL_OUT,
- .priority = NF_IP_PRI_CONNTRACK_DEFRAG,
- },
- {
.hook = ipv4_conntrack_local,
.owner = THIS_MODULE,
.pf = PF_INET,
@@ -422,6 +371,7 @@
int ret = 0;
need_conntrack();
+ nf_defrag_ipv4_enable();
ret = nf_register_sockopt(&so_getorigdst);
if (ret < 0) {