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-rw-r--r--net/ipv4/netfilter/Kconfig5
-rw-r--r--net/ipv4/netfilter/Makefile3
-rw-r--r--net/ipv4/netfilter/nf_conntrack_l3proto_ipv4.c56
-rw-r--r--net/ipv4/netfilter/nf_defrag_ipv4.c96
4 files changed, 107 insertions, 53 deletions
diff --git a/net/ipv4/netfilter/Kconfig b/net/ipv4/netfilter/Kconfig
index 4e842d56642..07757ac8d5d 100644
--- a/net/ipv4/netfilter/Kconfig
+++ b/net/ipv4/netfilter/Kconfig
@@ -5,10 +5,15 @@
menu "IP: Netfilter Configuration"
depends on INET && NETFILTER
+config NF_DEFRAG_IPV4
+ tristate
+ default n
+
config NF_CONNTRACK_IPV4
tristate "IPv4 connection tracking support (required for NAT)"
depends on NF_CONNTRACK
default m if NETFILTER_ADVANCED=n
+ select NF_DEFRAG_IPV4
---help---
Connection tracking keeps a record of what packets have passed
through your machine, in order to figure out how they are related
diff --git a/net/ipv4/netfilter/Makefile b/net/ipv4/netfilter/Makefile
index 1107edbe478..5f9b650d90f 100644
--- a/net/ipv4/netfilter/Makefile
+++ b/net/ipv4/netfilter/Makefile
@@ -18,6 +18,9 @@ obj-$(CONFIG_NF_CONNTRACK_IPV4) += nf_conntrack_ipv4.o
obj-$(CONFIG_NF_NAT) += nf_nat.o
+# defrag
+obj-$(CONFIG_NF_DEFRAG_IPV4) += nf_defrag_ipv4.o
+
# NAT helpers (nf_conntrack)
obj-$(CONFIG_NF_NAT_AMANDA) += nf_nat_amanda.o
obj-$(CONFIG_NF_NAT_FTP) += nf_nat_ftp.o
diff --git a/net/ipv4/netfilter/nf_conntrack_l3proto_ipv4.c b/net/ipv4/netfilter/nf_conntrack_l3proto_ipv4.c
index af69acc1d0f..4a7c3527539 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 @@ static int ipv4_print_tuple(struct seq_file *s,
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 @@ out:
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 @@ static unsigned int ipv4_conntrack_local(unsigned int hooknum,
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 @@ static struct nf_hook_ops ipv4_conntrack_ops[] __read_mostly = {
.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 @@ static int __init nf_conntrack_l3proto_ipv4_init(void)
int ret = 0;
need_conntrack();
+ nf_defrag_ipv4_enable();
ret = nf_register_sockopt(&so_getorigdst);
if (ret < 0) {
diff --git a/net/ipv4/netfilter/nf_defrag_ipv4.c b/net/ipv4/netfilter/nf_defrag_ipv4.c
new file mode 100644
index 00000000000..aa2c50a180f
--- /dev/null
+++ b/net/ipv4/netfilter/nf_defrag_ipv4.c
@@ -0,0 +1,96 @@
+/* (C) 1999-2001 Paul `Rusty' Russell
+ * (C) 2002-2004 Netfilter Core Team <coreteam@netfilter.org>
+ *
+ * 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/types.h>
+#include <linux/ip.h>
+#include <linux/netfilter.h>
+#include <linux/module.h>
+#include <linux/skbuff.h>
+#include <net/route.h>
+#include <net/ip.h>
+
+#include <linux/netfilter_ipv4.h>
+#include <net/netfilter/ipv4/nf_defrag_ipv4.h>
+
+/* 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 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 *))
+{
+#if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
+ /* Previously seen (loopback)? Ignore. Do this before
+ fragment check. */
+ if (skb->nfct)
+ return NF_ACCEPT;
+#endif
+
+ /* 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 struct nf_hook_ops ipv4_defrag_ops[] = {
+ {
+ .hook = ipv4_conntrack_defrag,
+ .owner = THIS_MODULE,
+ .pf = PF_INET,
+ .hooknum = NF_INET_PRE_ROUTING,
+ .priority = NF_IP_PRI_CONNTRACK_DEFRAG,
+ },
+ {
+ .hook = ipv4_conntrack_defrag,
+ .owner = THIS_MODULE,
+ .pf = PF_INET,
+ .hooknum = NF_INET_LOCAL_OUT,
+ .priority = NF_IP_PRI_CONNTRACK_DEFRAG,
+ },
+};
+
+static int __init nf_defrag_init(void)
+{
+ return nf_register_hooks(ipv4_defrag_ops, ARRAY_SIZE(ipv4_defrag_ops));
+}
+
+static void __exit nf_defrag_fini(void)
+{
+ nf_unregister_hooks(ipv4_defrag_ops, ARRAY_SIZE(ipv4_defrag_ops));
+}
+
+void nf_defrag_ipv4_enable(void)
+{
+}
+EXPORT_SYMBOL_GPL(nf_defrag_ipv4_enable);
+
+module_init(nf_defrag_init);
+module_exit(nf_defrag_fini);
+
+MODULE_LICENSE("GPL");
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2024-12-29 10:08:28 +0000