1 /* (C) 1999-2001 Paul `Rusty' Russell
2 * (C) 2002-2006 Netfilter Core Team <coreteam@netfilter.org>
3 * (C) 2008 Patrick McHardy <kaber@trash.net>
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License version 2 as
7 * published by the Free Software Foundation.
10 #include <linux/types.h>
11 #include <linux/init.h>
12 #include <linux/udp.h>
14 #include <linux/netfilter.h>
15 #include <linux/module.h>
16 #include <net/netfilter/nf_nat.h>
17 #include <net/netfilter/nf_nat_l3proto.h>
18 #include <net/netfilter/nf_nat_l4proto.h>
20 static u16 udplite_port_rover
;
23 udplite_unique_tuple(const struct nf_nat_l3proto
*l3proto
,
24 struct nf_conntrack_tuple
*tuple
,
25 const struct nf_nat_range
*range
,
26 enum nf_nat_manip_type maniptype
,
27 const struct nf_conn
*ct
)
29 nf_nat_l4proto_unique_tuple(l3proto
, tuple
, range
, maniptype
, ct
,
34 udplite_manip_pkt(struct sk_buff
*skb
,
35 const struct nf_nat_l3proto
*l3proto
,
36 unsigned int iphdroff
, unsigned int hdroff
,
37 const struct nf_conntrack_tuple
*tuple
,
38 enum nf_nat_manip_type maniptype
)
41 __be16
*portptr
, newport
;
43 if (!skb_make_writable(skb
, hdroff
+ sizeof(*hdr
)))
46 hdr
= (struct udphdr
*)(skb
->data
+ hdroff
);
48 if (maniptype
== NF_NAT_MANIP_SRC
) {
49 /* Get rid of source port */
50 newport
= tuple
->src
.u
.udp
.port
;
51 portptr
= &hdr
->source
;
53 /* Get rid of dst port */
54 newport
= tuple
->dst
.u
.udp
.port
;
58 l3proto
->csum_update(skb
, iphdroff
, &hdr
->check
, tuple
, maniptype
);
59 inet_proto_csum_replace2(&hdr
->check
, skb
, *portptr
, newport
, 0);
61 hdr
->check
= CSUM_MANGLED_0
;
67 static const struct nf_nat_l4proto nf_nat_l4proto_udplite
= {
68 .l4proto
= IPPROTO_UDPLITE
,
69 .manip_pkt
= udplite_manip_pkt
,
70 .in_range
= nf_nat_l4proto_in_range
,
71 .unique_tuple
= udplite_unique_tuple
,
72 #if IS_ENABLED(CONFIG_NF_CT_NETLINK)
73 .nlattr_to_range
= nf_nat_l4proto_nlattr_to_range
,
77 static int __init
nf_nat_proto_udplite_init(void)
81 err
= nf_nat_l4proto_register(NFPROTO_IPV4
, &nf_nat_l4proto_udplite
);
84 err
= nf_nat_l4proto_register(NFPROTO_IPV6
, &nf_nat_l4proto_udplite
);
90 nf_nat_l4proto_unregister(NFPROTO_IPV4
, &nf_nat_l4proto_udplite
);
95 static void __exit
nf_nat_proto_udplite_fini(void)
97 nf_nat_l4proto_unregister(NFPROTO_IPV6
, &nf_nat_l4proto_udplite
);
98 nf_nat_l4proto_unregister(NFPROTO_IPV4
, &nf_nat_l4proto_udplite
);
101 module_init(nf_nat_proto_udplite_init
);
102 module_exit(nf_nat_proto_udplite_fini
);
104 MODULE_LICENSE("GPL");
105 MODULE_DESCRIPTION("UDP-Lite NAT protocol helper");
106 MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>");