net: move the ct helper function to nf_conntrack_helper for ovs and tc

Move ovs_ct_helper from openvswitch to nf_conntrack_helper and rename
as nf_ct_helper so that it can be used in TC act_ct in the next patch.
Note that it also adds the checks for the family and proto, as in TC
act_ct, the packets with correct family and proto are not guaranteed.

Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

1 files changed, 1 insertions, 60 deletions

diff --git a/net/openvswitch/conntrack.c b/net/openvswitch/conntrack.c
index c7b10234cf7c..18f54fa38e8f 100644
--- a/net/openvswitch/conntrack.c
+++ b/net/openvswitch/conntrack.c
@@ -434,65 +434,6 @@ static int ovs_ct_set_labels(struct nf_conn *ct, struct sw_flow_key *key,
 	return 0;
 }
 
-/* 'skb' should already be pulled to nh_ofs. */
-static int ovs_ct_helper(struct sk_buff *skb, u16 proto)
-{
-	const struct nf_conntrack_helper *helper;
-	const struct nf_conn_help *help;
-	enum ip_conntrack_info ctinfo;
-	unsigned int protoff;
-	struct nf_conn *ct;
-	int err;
-
-	ct = nf_ct_get(skb, &ctinfo);
-	if (!ct || ctinfo == IP_CT_RELATED_REPLY)
-		return NF_ACCEPT;
-
-	help = nfct_help(ct);
-	if (!help)
-		return NF_ACCEPT;
-
-	helper = rcu_dereference(help->helper);
-	if (!helper)
-		return NF_ACCEPT;
-
-	switch (proto) {
-	case NFPROTO_IPV4:
-		protoff = ip_hdrlen(skb);
-		break;
-	case NFPROTO_IPV6: {
-		u8 nexthdr = ipv6_hdr(skb)->nexthdr;
-		__be16 frag_off;
-		int ofs;
-
-		ofs = ipv6_skip_exthdr(skb, sizeof(struct ipv6hdr), &nexthdr,
-				       &frag_off);
-		if (ofs < 0 || (frag_off & htons(~0x7)) != 0) {
-			pr_debug("proto header not found\n");
-			return NF_ACCEPT;
-		}
-		protoff = ofs;
-		break;
-	}
-	default:
-		WARN_ONCE(1, "helper invoked on non-IP family!");
-		return NF_DROP;
-	}
-
-	err = helper->help(skb, protoff, ct, ctinfo);
-	if (err != NF_ACCEPT)
-		return err;
-
-	/* Adjust seqs after helper.  This is needed due to some helpers (e.g.,
-	 * FTP with NAT) adusting the TCP payload size when mangling IP
-	 * addresses and/or port numbers in the text-based control connection.
-	 */
-	if (test_bit(IPS_SEQ_ADJUST_BIT, &ct->status) &&
-	    !nf_ct_seq_adjust(skb, ct, ctinfo, protoff))
-		return NF_DROP;
-	return NF_ACCEPT;
-}
-
 /* Returns 0 on success, -EINPROGRESS if 'skb' is stolen, or other nonzero
  * value if 'skb' is freed.
  */
@@ -1038,7 +979,7 @@ static int __ovs_ct_lookup(struct net *net, struct sw_flow_key *key,
 		 */
 		if ((nf_ct_is_confirmed(ct) ? !cached || add_helper :
 					      info->commit) &&
-		    ovs_ct_helper(skb, info->family) != NF_ACCEPT) {
+		    nf_ct_helper(skb, ct, ctinfo, info->family) != NF_ACCEPT) {
 			return -EINVAL;
 		}