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, 6 insertions, 5 deletions

diff --git a/net/netfilter/nfnetlink_cttimeout.c b/net/netfilter/nfnetlink_cttimeout.c
index 6ca0df7f416f..b48545b84ce8 100644
--- a/net/netfilter/nfnetlink_cttimeout.c
+++ b/net/netfilter/nfnetlink_cttimeout.c
@@ -122,7 +122,7 @@ static int cttimeout_new_timeout(struct net *net, struct sock *ctnl,
 		return -EBUSY;
 	}
 
-	l4proto = nf_ct_l4proto_find_get(l3num, l4num);
+	l4proto = nf_ct_l4proto_find_get(l4num);
 
 	/* This protocol is not supportted, skip. */
 	if (l4proto->l4proto != l4num) {
@@ -361,7 +361,7 @@ static int cttimeout_default_set(struct net *net, struct sock *ctnl,
 
 	l3num = ntohs(nla_get_be16(cda[CTA_TIMEOUT_L3PROTO]));
 	l4num = nla_get_u8(cda[CTA_TIMEOUT_L4PROTO]);
-	l4proto = nf_ct_l4proto_find_get(l3num, l4num);
+	l4proto = nf_ct_l4proto_find_get(l4num);
 
 	/* This protocol is not supported, skip. */
 	if (l4proto->l4proto != l4num) {
@@ -383,7 +383,7 @@ err:
 
 static int
 cttimeout_default_fill_info(struct net *net, struct sk_buff *skb, u32 portid,
-			    u32 seq, u32 type, int event,
+			    u32 seq, u32 type, int event, u16 l3num,
 			    const struct nf_conntrack_l4proto *l4proto)
 {
 	struct nlmsghdr *nlh;
@@ -402,7 +402,7 @@ cttimeout_default_fill_info(struct net *net, struct sk_buff *skb, u32 portid,
 	nfmsg->version = NFNETLINK_V0;
 	nfmsg->res_id = 0;
 
-	if (nla_put_be16(skb, CTA_TIMEOUT_L3PROTO, htons(l4proto->l3proto)) ||
+	if (nla_put_be16(skb, CTA_TIMEOUT_L3PROTO, htons(l3num)) ||
 	    nla_put_u8(skb, CTA_TIMEOUT_L4PROTO, l4proto->l4proto))
 		goto nla_put_failure;
 
@@ -442,7 +442,7 @@ static int cttimeout_default_get(struct net *net, struct sock *ctnl,
 
 	l3num = ntohs(nla_get_be16(cda[CTA_TIMEOUT_L3PROTO]));
 	l4num = nla_get_u8(cda[CTA_TIMEOUT_L4PROTO]);
-	l4proto = nf_ct_l4proto_find_get(l3num, l4num);
+	l4proto = nf_ct_l4proto_find_get(l4num);
 
 	/* This protocol is not supported, skip. */
 	if (l4proto->l4proto != l4num) {
@@ -460,6 +460,7 @@ static int cttimeout_default_get(struct net *net, struct sock *ctnl,
 					  nlh->nlmsg_seq,
 					  NFNL_MSG_TYPE(nlh->nlmsg_type),
 					  IPCTNL_MSG_TIMEOUT_DEFAULT_SET,
+					  l3num,
 					  l4proto);
 	if (ret <= 0) {
 		kfree_skb(skb2);