netfilter: nat: remove nf_nat_l4proto struct

This removes the (now empty) nf_nat_l4proto struct, all its instances
and all the no longer needed runtime (un)register functionality.

nf_nat_need_gre() can be axed as well: the module that calls it (to
load the no-longer-existing nat_gre module) also calls other nat core
functions. GRE nat is now always available if kernel is built with it.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

4 files changed, 4 insertions, 107 deletions

diff --git a/net/ipv4/netfilter/Makefile b/net/ipv4/netfilter/Makefile
index 367993adf4d3..fd7122e0e2c9 100644
--- a/net/ipv4/netfilter/Makefile
+++ b/net/ipv4/netfilter/Makefile
@@ -3,7 +3,7 @@
 # Makefile for the netfilter modules on top of IPv4.
 #
 
-nf_nat_ipv4-y		:= nf_nat_l3proto_ipv4.o nf_nat_proto_icmp.o
+nf_nat_ipv4-y		:= nf_nat_l3proto_ipv4.o
 nf_nat_ipv4-$(CONFIG_NF_NAT_MASQUERADE_IPV4) += nf_nat_masquerade_ipv4.o
 obj-$(CONFIG_NF_NAT_IPV4) += nf_nat_ipv4.o
 
@@ -28,9 +28,6 @@ nf_nat_snmp_basic-y := nf_nat_snmp_basic.asn1.o nf_nat_snmp_basic_main.o
 $(obj)/nf_nat_snmp_basic_main.o: $(obj)/nf_nat_snmp_basic.asn1.h
 obj-$(CONFIG_NF_NAT_SNMP_BASIC) += nf_nat_snmp_basic.o
 
-# NAT protocols (nf_nat)
-obj-$(CONFIG_NF_NAT_PROTO_GRE) += nf_nat_proto_gre.o
-
 obj-$(CONFIG_NFT_CHAIN_ROUTE_IPV4) += nft_chain_route_ipv4.o
 obj-$(CONFIG_NFT_CHAIN_NAT_IPV4) += nft_chain_nat_ipv4.o
 obj-$(CONFIG_NFT_REJECT_IPV4) += nft_reject_ipv4.o
diff --git a/net/ipv4/netfilter/nf_nat_l3proto_ipv4.c b/net/ipv4/netfilter/nf_nat_l3proto_ipv4.c
index 65fdb7a74621..2687db015b6f 100644
--- a/net/ipv4/netfilter/nf_nat_l3proto_ipv4.c
+++ b/net/ipv4/netfilter/nf_nat_l3proto_ipv4.c
@@ -64,7 +64,6 @@ static void nf_nat_ipv4_decode_session(struct sk_buff *skb,
 
 static bool nf_nat_ipv4_manip_pkt(struct sk_buff *skb,
 				  unsigned int iphdroff,
-				  const struct nf_nat_l4proto *l4proto,
 				  const struct nf_conntrack_tuple *target,
 				  enum nf_nat_manip_type maniptype)
 {
@@ -171,7 +170,6 @@ int nf_nat_icmp_reply_translation(struct sk_buff *skb,
 	enum ip_conntrack_dir dir = CTINFO2DIR(ctinfo);
 	enum nf_nat_manip_type manip = HOOK2MANIP(hooknum);
 	unsigned int hdrlen = ip_hdrlen(skb);
-	const struct nf_nat_l4proto *l4proto;
 	struct nf_conntrack_tuple target;
 	unsigned long statusbit;
 
@@ -202,9 +200,8 @@ int nf_nat_icmp_reply_translation(struct sk_buff *skb,
 	if (!(ct->status & statusbit))
 		return 1;
 
-	l4proto = __nf_nat_l4proto_find(NFPROTO_IPV4, inside->ip.protocol);
 	if (!nf_nat_ipv4_manip_pkt(skb, hdrlen + sizeof(inside->icmp),
-				   l4proto, &ct->tuplehash[!dir].tuple, !manip))
+				   &ct->tuplehash[!dir].tuple, !manip))
 		return 0;
 
 	if (skb->ip_summed != CHECKSUM_PARTIAL) {
@@ -218,8 +215,7 @@ int nf_nat_icmp_reply_translation(struct sk_buff *skb,
 
 	/* Change outer to look like the reply to an incoming packet */
 	nf_ct_invert_tuplepr(&target, &ct->tuplehash[!dir].tuple);
-	l4proto = __nf_nat_l4proto_find(NFPROTO_IPV4, 0);
-	if (!nf_nat_ipv4_manip_pkt(skb, 0, l4proto, &target, manip))
+	if (!nf_nat_ipv4_manip_pkt(skb, 0, &target, manip))
 		return 0;
 
 	return 1;
@@ -376,26 +372,12 @@ EXPORT_SYMBOL_GPL(nf_nat_l3proto_ipv4_unregister_fn);
 
 static int __init nf_nat_l3proto_ipv4_init(void)
 {
-	int err;
-
-	err = nf_nat_l4proto_register(NFPROTO_IPV4, &nf_nat_l4proto_icmp);
-	if (err < 0)
-		goto err1;
-	err = nf_nat_l3proto_register(&nf_nat_l3proto_ipv4);
-	if (err < 0)
-		goto err2;
-	return err;
-
-err2:
-	nf_nat_l4proto_unregister(NFPROTO_IPV4, &nf_nat_l4proto_icmp);
-err1:
-	return err;
+	return nf_nat_l3proto_register(&nf_nat_l3proto_ipv4);
 }
 
 static void __exit nf_nat_l3proto_ipv4_exit(void)
 {
 	nf_nat_l3proto_unregister(&nf_nat_l3proto_ipv4);
-	nf_nat_l4proto_unregister(NFPROTO_IPV4, &nf_nat_l4proto_icmp);
 }
 
 MODULE_LICENSE("GPL");
diff --git a/net/ipv4/netfilter/nf_nat_proto_gre.c b/net/ipv4/netfilter/nf_nat_proto_gre.c
deleted file mode 100644
index 25849295d537..000000000000
--- a/net/ipv4/netfilter/nf_nat_proto_gre.c
+++ /dev/null
@@ -1,61 +0,0 @@
-/*
- * nf_nat_proto_gre.c
- *
- * NAT protocol helper module for GRE.
- *
- * GRE is a generic encapsulation protocol, which is generally not very
- * suited for NAT, as it has no protocol-specific part as port numbers.
- *
- * It has an optional key field, which may help us distinguishing two
- * connections between the same two hosts.
- *
- * GRE is defined in RFC 1701 and RFC 1702, as well as RFC 2784
- *
- * PPTP is built on top of a modified version of GRE, and has a mandatory
- * field called "CallID", which serves us for the same purpose as the key
- * field in plain GRE.
- *
- * Documentation about PPTP can be found in RFC 2637
- *
- * (C) 2000-2005 by Harald Welte <laforge@gnumonks.org>
- *
- * Development of this code funded by Astaro AG (http://www.astaro.com/)
- *
- * (C) 2006-2012 Patrick McHardy <kaber@trash.net>
- *
- */
-
-#include <linux/module.h>
-#include <linux/skbuff.h>
-#include <linux/ip.h>
-
-#include <net/netfilter/nf_nat.h>
-#include <net/netfilter/nf_nat_l4proto.h>
-#include <linux/netfilter/nf_conntrack_proto_gre.h>
-
-MODULE_LICENSE("GPL");
-MODULE_AUTHOR("Harald Welte <laforge@gnumonks.org>");
-MODULE_DESCRIPTION("Netfilter NAT protocol helper module for GRE");
-
-static const struct nf_nat_l4proto gre = {
-	.l4proto		= IPPROTO_GRE,
-};
-
-static int __init nf_nat_proto_gre_init(void)
-{
-	return nf_nat_l4proto_register(NFPROTO_IPV4, &gre);
-}
-
-static void __exit nf_nat_proto_gre_fini(void)
-{
-	nf_nat_l4proto_unregister(NFPROTO_IPV4, &gre);
-}
-
-module_init(nf_nat_proto_gre_init);
-module_exit(nf_nat_proto_gre_fini);
-
-void nf_nat_need_gre(void)
-{
-	return;
-}
-EXPORT_SYMBOL_GPL(nf_nat_need_gre);
diff --git a/net/ipv4/netfilter/nf_nat_proto_icmp.c b/net/ipv4/netfilter/nf_nat_proto_icmp.c
deleted file mode 100644
index c2b7fd1a997b..000000000000
--- a/net/ipv4/netfilter/nf_nat_proto_icmp.c
+++ /dev/null
@@ -1,21 +0,0 @@
-/* (C) 1999-2001 Paul `Rusty' Russell
- * (C) 2002-2006 Netfilter Core Team <coreteam@netfilter.org>
- *
- * 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/export.h>
-#include <linux/ip.h>
-
-#include <linux/netfilter.h>
-#include <net/netfilter/nf_nat.h>
-#include <net/netfilter/nf_nat_core.h>
-#include <net/netfilter/nf_nat_l4proto.h>
-
-const struct nf_nat_l4proto nf_nat_l4proto_icmp = {
-	.l4proto		= IPPROTO_ICMP,
-};