netfilter: conntrack: remove l3->l4 mapping information

l4 protocols are demuxed by l3num, l4num pair.

However, almost all l4 trackers are l3 agnostic.

Only exceptions are:
 - gre, icmp (ipv4 only)
 - icmpv6 (ipv6 only)

This commit gets rid of the l3 mapping, l4 trackers can now be looked up
by their IPPROTO_XXX value alone, which gets rid of the additional l3
indirection.

For icmp, ipcmp6 and gre, add a check on state->pf and
return -NF_ACCEPT in case we're asked to track e.g. icmpv6-in-ipv4,
this seems more fitting than using the generic tracker.

Additionally we can kill the 2nd l4proto definitions that were needed
for v4/v6 split -- they are now the same so we can use single l4proto
struct for each protocol, rather than two.

The EXPORT_SYMBOLs can be removed as all these object files are
part of nf_conntrack with no external references.

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

1 files changed, 1 insertions, 34 deletions

diff --git a/net/netfilter/nf_conntrack_proto_dccp.c b/net/netfilter/nf_conntrack_proto_dccp.c
index d22852ae2316..171e9e122e5f 100644
--- a/net/netfilter/nf_conntrack_proto_dccp.c
+++ b/net/netfilter/nf_conntrack_proto_dccp.c
@@ -842,8 +842,7 @@ static struct nf_proto_net *dccp_get_net_proto(struct net *net)
 	return &net->ct.nf_ct_proto.dccp.pn;
 }
 
-const struct nf_conntrack_l4proto nf_conntrack_l4proto_dccp4 = {
-	.l3proto		= AF_INET,
+const struct nf_conntrack_l4proto nf_conntrack_l4proto_dccp = {
 	.l4proto		= IPPROTO_DCCP,
 	.packet			= dccp_packet,
 	.can_early_drop		= dccp_can_early_drop,
@@ -871,35 +870,3 @@ const struct nf_conntrack_l4proto nf_conntrack_l4proto_dccp4 = {
 	.init_net		= dccp_init_net,
 	.get_net_proto		= dccp_get_net_proto,
 };
-EXPORT_SYMBOL_GPL(nf_conntrack_l4proto_dccp4);
-
-const struct nf_conntrack_l4proto nf_conntrack_l4proto_dccp6 = {
-	.l3proto		= AF_INET6,
-	.l4proto		= IPPROTO_DCCP,
-	.packet			= dccp_packet,
-	.can_early_drop		= dccp_can_early_drop,
-#ifdef CONFIG_NF_CONNTRACK_PROCFS
-	.print_conntrack	= dccp_print_conntrack,
-#endif
-#if IS_ENABLED(CONFIG_NF_CT_NETLINK)
-	.nlattr_size		= DCCP_NLATTR_SIZE,
-	.to_nlattr		= dccp_to_nlattr,
-	.from_nlattr		= nlattr_to_dccp,
-	.tuple_to_nlattr	= nf_ct_port_tuple_to_nlattr,
-	.nlattr_tuple_size	= nf_ct_port_nlattr_tuple_size,
-	.nlattr_to_tuple	= nf_ct_port_nlattr_to_tuple,
-	.nla_policy		= nf_ct_port_nla_policy,
-#endif
-#ifdef CONFIG_NF_CONNTRACK_TIMEOUT
-	.ctnl_timeout		= {
-		.nlattr_to_obj	= dccp_timeout_nlattr_to_obj,
-		.obj_to_nlattr	= dccp_timeout_obj_to_nlattr,
-		.nlattr_max	= CTA_TIMEOUT_DCCP_MAX,
-		.obj_size	= sizeof(unsigned int) * CT_DCCP_MAX,
-		.nla_policy	= dccp_timeout_nla_policy,
-	},
-#endif /* CONFIG_NF_CONNTRACK_TIMEOUT */
-	.init_net		= dccp_init_net,
-	.get_net_proto		= dccp_get_net_proto,
-};
-EXPORT_SYMBOL_GPL(nf_conntrack_l4proto_dccp6);