Patrick McHardy | 9d908a6 | 2008-04-14 11:15:50 +0200 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (c) 2008 Patrick McHardy <kaber@trash.net> |
| 3 | * |
| 4 | * This program is free software; you can redistribute it and/or modify |
| 5 | * it under the terms of the GNU General Public License version 2 as |
| 6 | * published by the Free Software Foundation. |
| 7 | */ |
| 8 | |
| 9 | #include <linux/types.h> |
| 10 | #include <linux/init.h> |
Patrick McHardy | 9d908a6 | 2008-04-14 11:15:50 +0200 | [diff] [blame] | 11 | #include <linux/sctp.h> |
Paul Gortmaker | 3a9a231 | 2011-05-27 09:12:25 -0400 | [diff] [blame] | 12 | #include <linux/module.h> |
Patrick McHardy | 9d908a6 | 2008-04-14 11:15:50 +0200 | [diff] [blame] | 13 | #include <net/sctp/checksum.h> |
| 14 | |
Patrick McHardy | c7232c9 | 2012-08-26 19:14:06 +0200 | [diff] [blame] | 15 | #include <net/netfilter/nf_nat_l4proto.h> |
Patrick McHardy | 9d908a6 | 2008-04-14 11:15:50 +0200 | [diff] [blame] | 16 | |
| 17 | static u_int16_t nf_sctp_port_rover; |
| 18 | |
Changli Gao | f43dc98 | 2010-08-02 17:20:54 +0200 | [diff] [blame] | 19 | static void |
Patrick McHardy | c7232c9 | 2012-08-26 19:14:06 +0200 | [diff] [blame] | 20 | sctp_unique_tuple(const struct nf_nat_l3proto *l3proto, |
| 21 | struct nf_conntrack_tuple *tuple, |
| 22 | const struct nf_nat_range *range, |
Patrick McHardy | 9d908a6 | 2008-04-14 11:15:50 +0200 | [diff] [blame] | 23 | enum nf_nat_manip_type maniptype, |
| 24 | const struct nf_conn *ct) |
| 25 | { |
Patrick McHardy | c7232c9 | 2012-08-26 19:14:06 +0200 | [diff] [blame] | 26 | nf_nat_l4proto_unique_tuple(l3proto, tuple, range, maniptype, ct, |
| 27 | &nf_sctp_port_rover); |
Patrick McHardy | 9d908a6 | 2008-04-14 11:15:50 +0200 | [diff] [blame] | 28 | } |
| 29 | |
Jan Engelhardt | f2ea825 | 2008-04-14 11:15:53 +0200 | [diff] [blame] | 30 | static bool |
Patrick McHardy | 9d908a6 | 2008-04-14 11:15:50 +0200 | [diff] [blame] | 31 | sctp_manip_pkt(struct sk_buff *skb, |
Patrick McHardy | c7232c9 | 2012-08-26 19:14:06 +0200 | [diff] [blame] | 32 | const struct nf_nat_l3proto *l3proto, |
| 33 | unsigned int iphdroff, unsigned int hdroff, |
Patrick McHardy | 9d908a6 | 2008-04-14 11:15:50 +0200 | [diff] [blame] | 34 | const struct nf_conntrack_tuple *tuple, |
| 35 | enum nf_nat_manip_type maniptype) |
| 36 | { |
Patrick McHardy | 9d908a6 | 2008-04-14 11:15:50 +0200 | [diff] [blame] | 37 | sctp_sctphdr_t *hdr; |
Patrick McHardy | 9d908a6 | 2008-04-14 11:15:50 +0200 | [diff] [blame] | 38 | |
| 39 | if (!skb_make_writable(skb, hdroff + sizeof(*hdr))) |
Jan Engelhardt | f2ea825 | 2008-04-14 11:15:53 +0200 | [diff] [blame] | 40 | return false; |
Patrick McHardy | 9d908a6 | 2008-04-14 11:15:50 +0200 | [diff] [blame] | 41 | |
Patrick McHardy | 9d908a6 | 2008-04-14 11:15:50 +0200 | [diff] [blame] | 42 | hdr = (struct sctphdr *)(skb->data + hdroff); |
| 43 | |
Patrick McHardy | cbc9f2f | 2011-12-23 13:59:49 +0100 | [diff] [blame] | 44 | if (maniptype == NF_NAT_MANIP_SRC) { |
Patrick McHardy | c7232c9 | 2012-08-26 19:14:06 +0200 | [diff] [blame] | 45 | /* Get rid of src port */ |
Patrick McHardy | 9d908a6 | 2008-04-14 11:15:50 +0200 | [diff] [blame] | 46 | hdr->source = tuple->src.u.sctp.port; |
| 47 | } else { |
Patrick McHardy | c7232c9 | 2012-08-26 19:14:06 +0200 | [diff] [blame] | 48 | /* Get rid of dst port */ |
Patrick McHardy | 9d908a6 | 2008-04-14 11:15:50 +0200 | [diff] [blame] | 49 | hdr->dest = tuple->dst.u.sctp.port; |
| 50 | } |
| 51 | |
Joe Stringer | 024ec3d | 2013-07-25 10:52:05 +0900 | [diff] [blame] | 52 | hdr->checksum = sctp_compute_cksum(skb, hdroff); |
Patrick McHardy | 9d908a6 | 2008-04-14 11:15:50 +0200 | [diff] [blame] | 53 | |
Jan Engelhardt | f2ea825 | 2008-04-14 11:15:53 +0200 | [diff] [blame] | 54 | return true; |
Patrick McHardy | 9d908a6 | 2008-04-14 11:15:50 +0200 | [diff] [blame] | 55 | } |
| 56 | |
Patrick McHardy | c7232c9 | 2012-08-26 19:14:06 +0200 | [diff] [blame] | 57 | static const struct nf_nat_l4proto nf_nat_l4proto_sctp = { |
| 58 | .l4proto = IPPROTO_SCTP, |
Patrick McHardy | 9d908a6 | 2008-04-14 11:15:50 +0200 | [diff] [blame] | 59 | .manip_pkt = sctp_manip_pkt, |
Patrick McHardy | c7232c9 | 2012-08-26 19:14:06 +0200 | [diff] [blame] | 60 | .in_range = nf_nat_l4proto_in_range, |
Patrick McHardy | 9d908a6 | 2008-04-14 11:15:50 +0200 | [diff] [blame] | 61 | .unique_tuple = sctp_unique_tuple, |
Duan Jiong | 24de3d3 | 2014-06-30 09:19:32 +0800 | [diff] [blame] | 62 | #if IS_ENABLED(CONFIG_NF_CT_NETLINK) |
Patrick McHardy | c7232c9 | 2012-08-26 19:14:06 +0200 | [diff] [blame] | 63 | .nlattr_to_range = nf_nat_l4proto_nlattr_to_range, |
Patrick McHardy | 9d908a6 | 2008-04-14 11:15:50 +0200 | [diff] [blame] | 64 | #endif |
| 65 | }; |
| 66 | |
| 67 | static int __init nf_nat_proto_sctp_init(void) |
| 68 | { |
Patrick McHardy | c7232c9 | 2012-08-26 19:14:06 +0200 | [diff] [blame] | 69 | int err; |
| 70 | |
| 71 | err = nf_nat_l4proto_register(NFPROTO_IPV4, &nf_nat_l4proto_sctp); |
| 72 | if (err < 0) |
| 73 | goto err1; |
| 74 | err = nf_nat_l4proto_register(NFPROTO_IPV6, &nf_nat_l4proto_sctp); |
| 75 | if (err < 0) |
| 76 | goto err2; |
| 77 | return 0; |
| 78 | |
| 79 | err2: |
| 80 | nf_nat_l4proto_unregister(NFPROTO_IPV4, &nf_nat_l4proto_sctp); |
| 81 | err1: |
| 82 | return err; |
Patrick McHardy | 9d908a6 | 2008-04-14 11:15:50 +0200 | [diff] [blame] | 83 | } |
| 84 | |
| 85 | static void __exit nf_nat_proto_sctp_exit(void) |
| 86 | { |
Patrick McHardy | c7232c9 | 2012-08-26 19:14:06 +0200 | [diff] [blame] | 87 | nf_nat_l4proto_unregister(NFPROTO_IPV6, &nf_nat_l4proto_sctp); |
| 88 | nf_nat_l4proto_unregister(NFPROTO_IPV4, &nf_nat_l4proto_sctp); |
Patrick McHardy | 9d908a6 | 2008-04-14 11:15:50 +0200 | [diff] [blame] | 89 | } |
| 90 | |
| 91 | module_init(nf_nat_proto_sctp_init); |
| 92 | module_exit(nf_nat_proto_sctp_exit); |
| 93 | |
| 94 | MODULE_LICENSE("GPL"); |
| 95 | MODULE_DESCRIPTION("SCTP NAT protocol helper"); |
| 96 | MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>"); |