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diff -Nur linux-2.6.21.1/include/net/xfrmudp.h linux-2.6.21.1-owrt/include/net/xfrmudp.h
--- linux-2.6.21.1/include/net/xfrmudp.h 1970-01-01 01:00:00.000000000 +0100
+++ linux-2.6.21.1-owrt/include/net/xfrmudp.h 2007-05-14 11:26:11.000000000 +0200
@@ -0,0 +1,10 @@
+/*
+ * pointer to function for type that xfrm4_input wants, to permit
+ * decoupling of XFRM from udp.c
+ */
+#define HAVE_XFRM4_UDP_REGISTER
+
+typedef int (*xfrm4_rcv_encap_t)(struct sk_buff *skb, __u16 encap_type);
+extern int udp4_register_esp_rcvencap(xfrm4_rcv_encap_t func
+ , xfrm4_rcv_encap_t *oldfunc);
+extern int udp4_unregister_esp_rcvencap(xfrm4_rcv_encap_t func);
diff -Nur linux-2.6.21.1/net/ipv4/Kconfig linux-2.6.21.1-owrt/net/ipv4/Kconfig
--- linux-2.6.21.1/net/ipv4/Kconfig 2007-04-27 23:49:26.000000000 +0200
+++ linux-2.6.21.1-owrt/net/ipv4/Kconfig 2007-05-14 11:26:11.000000000 +0200
@@ -266,6 +266,12 @@
Network), but can be distributed all over the Internet. If you want
to do that, say Y here and to "IP multicast routing" below.
+config IPSEC_NAT_TRAVERSAL
+ bool "IPSEC NAT-Traversal (KLIPS compatible)"
+ depends on INET
+ ---help---
+ Includes support for RFC3947/RFC3948 NAT-Traversal of ESP over UDP.
+
config IP_MROUTE
bool "IP: multicast routing"
depends on IP_MULTICAST
diff -Nur linux-2.6.21.1/net/ipv4/udp.c linux-2.6.21.1-owrt/net/ipv4/udp.c
--- linux-2.6.21.1/net/ipv4/udp.c 2007-04-27 23:49:26.000000000 +0200
+++ linux-2.6.21.1-owrt/net/ipv4/udp.c 2007-05-14 11:42:44.000000000 +0200
@@ -101,12 +101,15 @@
#include <net/route.h>
#include <net/checksum.h>
#include <net/xfrm.h>
+#include <net/xfrmudp.h>
#include "udp_impl.h"
/*
* Snmp MIB for the UDP layer
*/
+static xfrm4_rcv_encap_t xfrm4_rcv_encap_func;
+
DEFINE_SNMP_STAT(struct udp_mib, udp_statistics) __read_mostly;
struct hlist_head udp_hash[UDP_HTABLE_SIZE];
@@ -915,6 +918,42 @@
return 0;
}
+#if defined(CONFIG_XFRM) || defined(CONFIG_IPSEC_NAT_TRAVERSAL)
+
+/* if XFRM isn't a module, then register it directly. */
+#if 0 && !defined(CONFIG_XFRM_MODULE) && !defined(CONFIG_IPSEC_NAT_TRAVERSAL)
+static xfrm4_rcv_encap_t xfrm4_rcv_encap_func = xfrm4_rcv_encap;
+#else
+static xfrm4_rcv_encap_t xfrm4_rcv_encap_func = NULL;
+#endif
+
+int udp4_register_esp_rcvencap(xfrm4_rcv_encap_t func
+ , xfrm4_rcv_encap_t *oldfunc)
+{
+ if(oldfunc != NULL) {
+ *oldfunc = xfrm4_rcv_encap_func;
+ }
+
+#if 0
+ if(xfrm4_rcv_encap_func != NULL)
+ return -1;
+#endif
+
+ xfrm4_rcv_encap_func = func;
+ return 0;
+}
+
+int udp4_unregister_esp_rcvencap(xfrm4_rcv_encap_t func)
+{
+ if(xfrm4_rcv_encap_func != func)
+ return -1;
+
+ xfrm4_rcv_encap_func = NULL;
+ return 0;
+}
+#endif /* CONFIG_XFRM_MODULE || CONFIG_IPSEC_NAT_TRAVERSAL */
+
+
/* return:
* 1 if the the UDP system should process it
* 0 if we should drop this packet
@@ -922,7 +961,7 @@
*/
static int udp_encap_rcv(struct sock * sk, struct sk_buff *skb)
{
-#ifndef CONFIG_XFRM
+#if !defined(CONFIG_XFRM) && !defined(CONFIG_IPSEC_NAT_TRAVERSAL)
return 1;
#else
struct udp_sock *up = udp_sk(sk);
@@ -937,11 +976,11 @@
/* if we're overly short, let UDP handle it */
len = skb->len - sizeof(struct udphdr);
if (len <= 0)
- return 1;
+ return 2;
/* if this is not encapsulated socket, then just return now */
if (!encap_type)
- return 1;
+ return 3;
/* If this is a paged skb, make sure we pull up
* whatever data we need to look at. */
@@ -964,7 +1003,7 @@
len = sizeof(struct udphdr);
} else
/* Must be an IKE packet.. pass it through */
- return 1;
+ return 4;
break;
case UDP_ENCAP_ESPINUDP_NON_IKE:
/* Check if this is a keepalive packet. If so, eat it. */
@@ -977,7 +1016,7 @@
len = sizeof(struct udphdr) + 2 * sizeof(u32);
} else
/* Must be an IKE packet.. pass it through */
- return 1;
+ return 5;
break;
}
@@ -988,6 +1027,8 @@
*/
if (skb_cloned(skb) && pskb_expand_head(skb, 0, 0, GFP_ATOMIC))
return 0;
+ if (skb_cloned(skb) && pskb_expand_head(skb, 0, 0, GFP_ATOMIC))
+ return 0;
/* Now we can update and verify the packet length... */
iph = skb->nh.iph;
@@ -1051,9 +1092,13 @@
return 0;
}
if (ret < 0) {
- /* process the ESP packet */
- ret = xfrm4_rcv_encap(skb, up->encap_type);
- UDP_INC_STATS_BH(UDP_MIB_INDATAGRAMS, up->pcflag);
+ if(xfrm4_rcv_encap_func != NULL) {
+ ret = (*xfrm4_rcv_encap_func)(skb, up->encap_type);
+ UDP_INC_STATS_BH(UDP_MIB_INDATAGRAMS, up->pcflag);
+ } else {
+ UDP_INC_STATS_BH(UDP_MIB_INERRORS, up->pcflag);
+ ret = 1;
+ }
return -ret;
}
/* FALLTHROUGH -- it's a UDP Packet */
@@ -1733,3 +1778,9 @@
EXPORT_SYMBOL(udp_proc_register);
EXPORT_SYMBOL(udp_proc_unregister);
#endif
+
+#if defined(CONFIG_IPSEC_NAT_TRAVERSAL)
+EXPORT_SYMBOL(udp4_register_esp_rcvencap);
+EXPORT_SYMBOL(udp4_unregister_esp_rcvencap);
+#endif
+
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