2 * Copyright (c) 2008 Patrick McHardy <kaber@trash.net>
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.
9 #include <linux/types.h>
10 #include <linux/sctp.h>
11 #include <net/sctp/checksum.h>
13 #include <net/netfilter/nf_nat_l4proto.h>
16 sctp_unique_tuple(const struct nf_nat_l3proto *l3proto,
17 struct nf_conntrack_tuple *tuple,
18 const struct nf_nat_range *range,
19 enum nf_nat_manip_type maniptype,
20 const struct nf_conn *ct)
22 nf_nat_l4proto_unique_tuple(l3proto, tuple, range, maniptype, ct);
26 sctp_manip_pkt(struct sk_buff *skb,
27 const struct nf_nat_l3proto *l3proto,
28 unsigned int iphdroff, unsigned int hdroff,
29 const struct nf_conntrack_tuple *tuple,
30 enum nf_nat_manip_type maniptype)
35 /* This could be an inner header returned in imcp packet; in such
36 * cases we cannot update the checksum field since it is outside
37 * of the 8 bytes of transport layer headers we are guaranteed.
39 if (skb->len >= hdroff + sizeof(*hdr))
40 hdrsize = sizeof(*hdr);
42 if (!skb_make_writable(skb, hdroff + hdrsize))
45 hdr = (struct sctphdr *)(skb->data + hdroff);
47 if (maniptype == NF_NAT_MANIP_SRC) {
48 /* Get rid of src port */
49 hdr->source = tuple->src.u.sctp.port;
51 /* Get rid of dst port */
52 hdr->dest = tuple->dst.u.sctp.port;
55 if (hdrsize < sizeof(*hdr))
58 if (skb->ip_summed != CHECKSUM_PARTIAL) {
59 hdr->checksum = sctp_compute_cksum(skb, hdroff);
60 skb->ip_summed = CHECKSUM_NONE;
66 const struct nf_nat_l4proto nf_nat_l4proto_sctp = {
67 .l4proto = IPPROTO_SCTP,
68 .manip_pkt = sctp_manip_pkt,
69 .in_range = nf_nat_l4proto_in_range,
70 .unique_tuple = sctp_unique_tuple,
71 #if IS_ENABLED(CONFIG_NF_CT_NETLINK)
72 .nlattr_to_range = nf_nat_l4proto_nlattr_to_range,