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, 1 deletions

diff --git a/net/netfilter/nft_ct.c b/net/netfilter/nft_ct.c
index 17ae5059c312..d74afa70774f 100644
--- a/net/netfilter/nft_ct.c
+++ b/net/netfilter/nft_ct.c
@@ -855,7 +855,7 @@ static int nft_ct_timeout_obj_init(const struct nft_ctx *ctx,
 	l4num = nla_get_u8(tb[NFTA_CT_TIMEOUT_L4PROTO]);
 	priv->l4proto = l4num;
 
-	l4proto = nf_ct_l4proto_find_get(l3num, l4num);
+	l4proto = nf_ct_l4proto_find_get(l4num);
 
 	if (l4proto->l4proto != l4num) {
 		ret = -EOPNOTSUPP;