netfilter: nf_conntrack: split up IPCT_STATUS event

Split up the IPCT_STATUS event into an IPCT_REPLY event, which is generated
when the IPS_SEEN_REPLY bit is set, and an IPCT_ASSURED event, which is
generated when the IPS_ASSURED bit is set.

In combination with a following patch to support selective event delivery,
this can be used for "sparse" conntrack replication: start replicating the
conntrack entry after it reached the ASSURED state and that way it's SYN-flood
resistant.

Signed-off-by: Patrick McHardy <kaber@trash.net>
diff --git a/net/netfilter/nf_conntrack_core.c b/net/netfilter/nf_conntrack_core.c
index 0e98c32..091ff77 100644
--- a/net/netfilter/nf_conntrack_core.c
+++ b/net/netfilter/nf_conntrack_core.c
@@ -825,7 +825,7 @@
 	}
 
 	if (set_reply && !test_and_set_bit(IPS_SEEN_REPLY_BIT, &ct->status))
-		nf_conntrack_event_cache(IPCT_STATUS, ct);
+		nf_conntrack_event_cache(IPCT_REPLY, ct);
 
 	return ret;
 }
diff --git a/net/netfilter/nf_conntrack_netlink.c b/net/netfilter/nf_conntrack_netlink.c
index 16f86d6..ff594eb 100644
--- a/net/netfilter/nf_conntrack_netlink.c
+++ b/net/netfilter/nf_conntrack_netlink.c
@@ -1371,7 +1371,8 @@
 			else
 				events = IPCT_NEW;
 
-			nf_conntrack_eventmask_report((1 << IPCT_STATUS) |
+			nf_conntrack_eventmask_report((1 << IPCT_REPLY) |
+						      (1 << IPCT_ASSURED) |
 						      (1 << IPCT_HELPER) |
 						      (1 << IPCT_PROTOINFO) |
 						      (1 << IPCT_NATSEQADJ) |
@@ -1396,7 +1397,8 @@
 		if (err == 0) {
 			nf_conntrack_get(&ct->ct_general);
 			spin_unlock_bh(&nf_conntrack_lock);
-			nf_conntrack_eventmask_report((1 << IPCT_STATUS) |
+			nf_conntrack_eventmask_report((1 << IPCT_REPLY) |
+						      (1 << IPCT_ASSURED) |
 						      (1 << IPCT_HELPER) |
 						      (1 << IPCT_PROTOINFO) |
 						      (1 << IPCT_NATSEQADJ) |
diff --git a/net/netfilter/nf_conntrack_proto_gre.c b/net/netfilter/nf_conntrack_proto_gre.c
index c99cfba..d899b1a 100644
--- a/net/netfilter/nf_conntrack_proto_gre.c
+++ b/net/netfilter/nf_conntrack_proto_gre.c
@@ -241,7 +241,7 @@
 				   ct->proto.gre.stream_timeout);
 		/* Also, more likely to be important, and not a probe. */
 		set_bit(IPS_ASSURED_BIT, &ct->status);
-		nf_conntrack_event_cache(IPCT_STATUS, ct);
+		nf_conntrack_event_cache(IPCT_ASSURED, ct);
 	} else
 		nf_ct_refresh_acct(ct, ctinfo, skb,
 				   ct->proto.gre.timeout);
diff --git a/net/netfilter/nf_conntrack_proto_sctp.c b/net/netfilter/nf_conntrack_proto_sctp.c
index f9d930f..b68ff15 100644
--- a/net/netfilter/nf_conntrack_proto_sctp.c
+++ b/net/netfilter/nf_conntrack_proto_sctp.c
@@ -377,7 +377,7 @@
 	    new_state == SCTP_CONNTRACK_ESTABLISHED) {
 		pr_debug("Setting assured bit\n");
 		set_bit(IPS_ASSURED_BIT, &ct->status);
-		nf_conntrack_event_cache(IPCT_STATUS, ct);
+		nf_conntrack_event_cache(IPCT_ASSURED, ct);
 	}
 
 	return NF_ACCEPT;
diff --git a/net/netfilter/nf_conntrack_proto_tcp.c b/net/netfilter/nf_conntrack_proto_tcp.c
index 3c96437..ad11805 100644
--- a/net/netfilter/nf_conntrack_proto_tcp.c
+++ b/net/netfilter/nf_conntrack_proto_tcp.c
@@ -1045,7 +1045,7 @@
 		   after SYN_RECV or a valid answer for a picked up
 		   connection. */
 		set_bit(IPS_ASSURED_BIT, &ct->status);
-		nf_conntrack_event_cache(IPCT_STATUS, ct);
+		nf_conntrack_event_cache(IPCT_ASSURED, ct);
 	}
 	nf_ct_refresh_acct(ct, ctinfo, skb, timeout);
 
diff --git a/net/netfilter/nf_conntrack_proto_udp.c b/net/netfilter/nf_conntrack_proto_udp.c
index 5c5518b..8d38f9a 100644
--- a/net/netfilter/nf_conntrack_proto_udp.c
+++ b/net/netfilter/nf_conntrack_proto_udp.c
@@ -77,7 +77,7 @@
 		nf_ct_refresh_acct(ct, ctinfo, skb, nf_ct_udp_timeout_stream);
 		/* Also, more likely to be important, and not a probe */
 		if (!test_and_set_bit(IPS_ASSURED_BIT, &ct->status))
-			nf_conntrack_event_cache(IPCT_STATUS, ct);
+			nf_conntrack_event_cache(IPCT_ASSURED, ct);
 	} else
 		nf_ct_refresh_acct(ct, ctinfo, skb, nf_ct_udp_timeout);
 
diff --git a/net/netfilter/nf_conntrack_proto_udplite.c b/net/netfilter/nf_conntrack_proto_udplite.c
index 458655b..0b1bc9b 100644
--- a/net/netfilter/nf_conntrack_proto_udplite.c
+++ b/net/netfilter/nf_conntrack_proto_udplite.c
@@ -75,7 +75,7 @@
 				   nf_ct_udplite_timeout_stream);
 		/* Also, more likely to be important, and not a probe */
 		if (!test_and_set_bit(IPS_ASSURED_BIT, &ct->status))
-			nf_conntrack_event_cache(IPCT_STATUS, ct);
+			nf_conntrack_event_cache(IPCT_ASSURED, ct);
 	} else
 		nf_ct_refresh_acct(ct, ctinfo, skb, nf_ct_udplite_timeout);