Commit 9d908a69 authored by Patrick McHardy's avatar Patrick McHardy
Browse files

[NETFILTER]: nf_nat: add SCTP protocol support 



Signed-off-by: default avatarPatrick McHardy <kaber@trash.net>
parent 4910a087

net/ipv4/netfilter/Kconfig

+5 −0
Original line number Diff line number Diff line
@@ -255,6 +255,11 @@ config NF_NAT_PROTO_UDPLITE 
	depends on NF_NAT && NF_CT_PROTO_UDPLITE

	default NF_NAT && NF_CT_PROTO_UDPLITE



config NF_NAT_PROTO_SCTP

	tristate

	default NF_NAT && NF_CT_PROTO_SCTP

	depends on NF_NAT && NF_CT_PROTO_SCTP



config NF_NAT_FTP

	tristate

	depends on IP_NF_IPTABLES && NF_CONNTRACK && NF_NAT

net/ipv4/netfilter/Makefile

+1 −0
Original line number Diff line number Diff line
@@ -32,6 +32,7 @@ obj-$(CONFIG_NF_NAT_TFTP) += nf_nat_tftp.o 
obj-$(CONFIG_NF_NAT_PROTO_DCCP) += nf_nat_proto_dccp.o

obj-$(CONFIG_NF_NAT_PROTO_GRE) += nf_nat_proto_gre.o

obj-$(CONFIG_NF_NAT_PROTO_UDPLITE) += nf_nat_proto_udplite.o

obj-$(CONFIG_NF_NAT_PROTO_SCTP) += nf_nat_proto_sctp.o



# generic IP tables 

obj-$(CONFIG_IP_NF_IPTABLES) += ip_tables.o

net/ipv4/netfilter/nf_nat_proto_sctp.c

0 → 100644
+96 −0
Original line number Diff line number Diff line 
/*

 * Copyright (c) 2008 Patrick McHardy <kaber@trash.net>

 *

 * This program is free software; you can redistribute it and/or modify

 * it under the terms of the GNU General Public License version 2 as

 * published by the Free Software Foundation.

 */



#include <linux/types.h>

#include <linux/init.h>

#include <linux/ip.h>

#include <linux/sctp.h>

#include <net/sctp/checksum.h>



#include <net/netfilter/nf_nat_protocol.h>



static u_int16_t nf_sctp_port_rover;



static int

sctp_unique_tuple(struct nf_conntrack_tuple *tuple,

		  const struct nf_nat_range *range,

		  enum nf_nat_manip_type maniptype,

		  const struct nf_conn *ct)

{

	return nf_nat_proto_unique_tuple(tuple, range, maniptype, ct,

					 &nf_sctp_port_rover);

}



static int

sctp_manip_pkt(struct sk_buff *skb,

	       unsigned int iphdroff,

	       const struct nf_conntrack_tuple *tuple,

	       enum nf_nat_manip_type maniptype)

{

	const struct iphdr *iph = (struct iphdr *)(skb->data + iphdroff);

	sctp_sctphdr_t *hdr;

	unsigned int hdroff = iphdroff + iph->ihl*4;

	__be32 oldip, newip;

	u32 crc32;



	if (!skb_make_writable(skb, hdroff + sizeof(*hdr)))

		return 0;



	iph = (struct iphdr *)(skb->data + iphdroff);

	hdr = (struct sctphdr *)(skb->data + hdroff);



	if (maniptype == IP_NAT_MANIP_SRC) {

		/* Get rid of src ip and src pt */

		oldip = iph->saddr;

		newip = tuple->src.u3.ip;

		hdr->source = tuple->src.u.sctp.port;

	} else {

		/* Get rid of dst ip and dst pt */

		oldip = iph->daddr;

		newip = tuple->dst.u3.ip;

		hdr->dest = tuple->dst.u.sctp.port;

	}



	crc32 = sctp_start_cksum((u8 *)hdr, skb_headlen(skb) - hdroff);

	for (skb = skb_shinfo(skb)->frag_list; skb; skb = skb->next)

		crc32 = sctp_update_cksum((u8 *)skb->data, skb_headlen(skb),

					  crc32);

	crc32 = sctp_end_cksum(crc32);

	hdr->checksum = htonl(crc32);



	return 1;

}



static const struct nf_nat_protocol nf_nat_protocol_sctp = {

	.protonum		= IPPROTO_SCTP,

	.me			= THIS_MODULE,

	.manip_pkt		= sctp_manip_pkt,

	.in_range		= nf_nat_proto_in_range,

	.unique_tuple		= sctp_unique_tuple,

#if defined(CONFIG_NF_CT_NETLINK) || defined(CONFIG_NF_CT_NETLINK_MODULE)

	.range_to_nlattr	= nf_nat_proto_range_to_nlattr,

	.nlattr_to_range	= nf_nat_proto_nlattr_to_range,

#endif

};



static int __init nf_nat_proto_sctp_init(void)

{

	return nf_nat_protocol_register(&nf_nat_protocol_sctp);

}



static void __exit nf_nat_proto_sctp_exit(void)

{

	nf_nat_protocol_unregister(&nf_nat_protocol_sctp);

}



module_init(nf_nat_proto_sctp_init);

module_exit(nf_nat_proto_sctp_exit);



MODULE_LICENSE("GPL");

MODULE_DESCRIPTION("SCTP NAT protocol helper");

MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>");

net/ipv4/netfilter/nf_nat_standalone.c

+4 −2
Original line number Diff line number Diff line
@@ -52,7 +52,8 @@ static void nat_decode_session(struct sk_buff *skb, struct flowi *fl) 
		if (t->dst.protonum == IPPROTO_TCP ||

		    t->dst.protonum == IPPROTO_UDP ||

		    t->dst.protonum == IPPROTO_UDPLITE ||

		    t->dst.protonum == IPPROTO_DCCP)

		    t->dst.protonum == IPPROTO_DCCP ||

		    t->dst.protonum == IPPROTO_SCTP)

			fl->fl_ip_dport = t->dst.u.tcp.port;

	}
@@ -63,7 +64,8 @@ static void nat_decode_session(struct sk_buff *skb, struct flowi *fl) 
		if (t->dst.protonum == IPPROTO_TCP ||

		    t->dst.protonum == IPPROTO_UDP ||

		    t->dst.protonum == IPPROTO_UDPLITE ||

		    t->dst.protonum == IPPROTO_DCCP)

		    t->dst.protonum == IPPROTO_DCCP ||

		    t->dst.protonum == IPPROTO_SCTP)

			fl->fl_ip_sport = t->src.u.tcp.port;

	}

}