session manager: support session timeouts & tcp dupkt filter & udp eviction filter

src/session/session_private.h

@@ -22,8 +22,8 @@ enum tcp_ex_data
     TCP_SYN_RECVED = 1 << 0,
     TCP_SYNACK_RECVED = 1 << 1,
     // ESTABLISHED
-    TCP_C2S_PAYLOAD_RECVED = 1 << 2,
-    TCP_S2C_PAYLOAD_RECVED = 1 << 3,
+    TCP_C2S_DATA_RECVED = 1 << 2,
+    TCP_S2C_DATA_RECVED = 1 << 3,
     // FIN
     TCP_C2S_FIN_RECVED = 1 << 4,
     TCP_S2C_FIN_RECVED = 1 << 5,
@@ -49,6 +49,9 @@ struct session
     // session type
     enum session_type type;
 
+    // dup traffic flag
+    enum dup_traffic_flag dup_flag;
+
     // closing reasion
     enum closing_reasion closing_reasion;