[NETFILTER] ctnetlink: add one nesting level for TCP state

To keep consistency, the TCP private protocol information is nested
attributes under CTA_PROTOINFO_TCP. This way the sequence of attributes to
access the TCP state information looks like here below:

CTA_PROTOINFO
CTA_PROTOINFO_TCP
CTA_PROTOINFO_TCP_STATE

instead of:

CTA_PROTOINFO
CTA_PROTOINFO_TCP_STATE

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Harald Welte <laforge@netfilter.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

2 files changed, 12 insertions, 1 deletions

diff --git a/include/linux/netfilter/nfnetlink_conntrack.h b/include/linux/netfilter/nfnetlink_conntrack.h
index 5c55751c78e4..fb5511030185 100644
--- a/include/linux/netfilter/nfnetlink_conntrack.h
+++ b/include/linux/netfilter/nfnetlink_conntrack.h
@@ -70,11 +70,18 @@ enum ctattr_l4proto {
 
 enum ctattr_protoinfo {
         CTA_PROTOINFO_UNSPEC,
-        CTA_PROTOINFO_TCP_STATE,
+        CTA_PROTOINFO_TCP,
         __CTA_PROTOINFO_MAX
 };
 #define CTA_PROTOINFO_MAX (__CTA_PROTOINFO_MAX - 1)
 
+enum ctattr_protoinfo_tcp {
+        CTA_PROTOINFO_TCP_UNSPEC,
+        CTA_PROTOINFO_TCP_STATE,
+        __CTA_PROTOINFO_TCP_MAX
+};
+#define CTA_PROTOINFO_TCP_MAX (__CTA_PROTOINFO_TCP_MAX - 1)
+
 enum ctattr_counters {
         CTA_COUNTERS_UNSPEC,
         CTA_COUNTERS_PACKETS,
diff --git a/net/ipv4/netfilter/ip_conntrack_proto_tcp.c b/net/ipv4/netfilter/ip_conntrack_proto_tcp.c
index 121760d6cc50..75e27e65c28f 100644
--- a/net/ipv4/netfilter/ip_conntrack_proto_tcp.c
+++ b/net/ipv4/netfilter/ip_conntrack_proto_tcp.c
@@ -341,11 +341,15 @@ static int tcp_print_conntrack(struct seq_file *s,
 static int tcp_to_nfattr(struct sk_buff *skb, struct nfattr *nfa,
                          const struct ip_conntrack *ct)
 {
+        struct nfattr *nest_parms = NFA_NEST(skb, CTA_PROTOINFO_TCP);
+        
         read_lock_bh(&tcp_lock);
         NFA_PUT(skb, CTA_PROTOINFO_TCP_STATE, sizeof(u_int8_t),
                 &ct->proto.tcp.state);
         read_unlock_bh(&tcp_lock);
 
+        NFA_NEST_END(skb, nest_parms);
+
         return 0;
 
 nfattr_failure: