projects / linux-2.6-block.git / blame
| Commit | Line | Data |
|---|---|---|
| 6185f870 PM |
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> | |
| 4 | * | |
| 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. | |
| 8 | */ | |
| 9 | ||
| 10 | #include <linux/types.h> | |
| 11 | #include <linux/init.h> | |
| 12 | #include <linux/ip.h> | |
| 13 | #include <linux/udp.h> | |
| 14 | ||
| 15 | #include <linux/netfilter.h> | |
| 16 | #include <net/netfilter/nf_nat.h> | |
| 17 | #include <net/netfilter/nf_nat_protocol.h> | |
| 18 | ||
| 19 | static u_int16_t udplite_port_rover; | |
| 20 | ||
| f2ea825f | 21 | static bool |
| 6185f870 PM |
22 | udplite_unique_tuple(struct nf_conntrack_tuple *tuple, |
| 23 | const struct nf_nat_range *range, | |
| 24 | enum nf_nat_manip_type maniptype, | |
| 25 | const struct nf_conn *ct) | |
| 26 | { | |
| 27 | return nf_nat_proto_unique_tuple(tuple, range, maniptype, ct, | |
| 28 | &udplite_port_rover); | |
| 29 | } | |
| 30 | ||
| f2ea825f | 31 | static bool |
| 6185f870 PM |
32 | udplite_manip_pkt(struct sk_buff *skb, |
| 33 | unsigned int iphdroff, | |
| 34 | const struct nf_conntrack_tuple *tuple, | |
| 35 | enum nf_nat_manip_type maniptype) | |
| 36 | { | |
| 37 | const struct iphdr *iph = (struct iphdr *)(skb->data + iphdroff); | |
| 38 | struct udphdr *hdr; | |
| 39 | unsigned int hdroff = iphdroff + iph->ihl*4; | |
| 40 | __be32 oldip, newip; | |
| 41 | __be16 *portptr, newport; | |
| 42 | ||
| 43 | if (!skb_make_writable(skb, hdroff + sizeof(*hdr))) | |
| f2ea825f | 44 | return false; |
| 6185f870 PM |
45 | |
| 46 | iph = (struct iphdr *)(skb->data + iphdroff); | |
| 47 | hdr = (struct udphdr *)(skb->data + hdroff); | |
| 48 | ||
| 49 | if (maniptype == IP_NAT_MANIP_SRC) { | |
| 50 | /* Get rid of src ip and src pt */ | |
| 51 | oldip = iph->saddr; | |
| 52 | newip = tuple->src.u3.ip; | |
| 53 | newport = tuple->src.u.udp.port; | |
| 54 | portptr = &hdr->source; | |
| 55 | } else { | |
| 56 | /* Get rid of dst ip and dst pt */ | |
| 57 | oldip = iph->daddr; | |
| 58 | newip = tuple->dst.u3.ip; | |
| 59 | newport = tuple->dst.u.udp.port; | |
| 60 | portptr = &hdr->dest; | |
| 61 | } | |
| 62 | ||
| 63 | inet_proto_csum_replace4(&hdr->check, skb, oldip, newip, 1); | |
| 64 | inet_proto_csum_replace2(&hdr->check, skb, *portptr, newport, 0); | |
| 65 | if (!hdr->check) | |
| 66 | hdr->check = CSUM_MANGLED_0; | |
| 67 | ||
| 68 | *portptr = newport; | |
| f2ea825f | 69 | return true; |
| 6185f870 PM |
70 | } |
| 71 | ||
| 72 | static const struct nf_nat_protocol nf_nat_protocol_udplite = { | |
| 73 | .protonum = IPPROTO_UDPLITE, | |
| 74 | .me = THIS_MODULE, | |
| 75 | .manip_pkt = udplite_manip_pkt, | |
| 76 | .in_range = nf_nat_proto_in_range, | |
| 77 | .unique_tuple = udplite_unique_tuple, | |
| 78 | #if defined(CONFIG_NF_CT_NETLINK) || defined(CONFIG_NF_CT_NETLINK_MODULE) | |
| 79 | .range_to_nlattr = nf_nat_proto_range_to_nlattr, | |
| 80 | .nlattr_to_range = nf_nat_proto_nlattr_to_range, | |
| 81 | #endif | |
| 82 | }; | |
| 83 | ||
| 84 | static int __init nf_nat_proto_udplite_init(void) | |
| 85 | { | |
| 86 | return nf_nat_protocol_register(&nf_nat_protocol_udplite); | |
| 87 | } | |
| 88 | ||
| 89 | static void __exit nf_nat_proto_udplite_fini(void) | |
| 90 | { | |
| 91 | nf_nat_protocol_unregister(&nf_nat_protocol_udplite); | |
| 92 | } | |
| 93 | ||
| 94 | module_init(nf_nat_proto_udplite_init); | |
| 95 | module_exit(nf_nat_proto_udplite_fini); | |
| 96 | ||
| 97 | MODULE_LICENSE("GPL"); | |
| 98 | MODULE_DESCRIPTION("UDP-Lite NAT protocol helper"); | |
| 99 | MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>"); |