[ONOS-3857] BGP update message flow specification components parsing.

Change-Id: I9b58cdf2c47cb736a8119433cbc7911d871a83d1
diff --git a/protocols/bgp/bgpio/src/main/java/org/onosproject/bgpio/util/Constants.java b/protocols/bgp/bgpio/src/main/java/org/onosproject/bgpio/util/Constants.java
index 8d68742..e904313 100644
--- a/protocols/bgp/bgpio/src/main/java/org/onosproject/bgpio/util/Constants.java
+++ b/protocols/bgp/bgpio/src/main/java/org/onosproject/bgpio/util/Constants.java
@@ -68,4 +68,6 @@
     public static final short BGP_FLOWSPEC_ACTION_TRAFFIC_REDIRECT = (short) 0x8008;
     public static final short BGP_FLOWSPEC_ACTION_TRAFFIC_MARKING = (short) 0x8009;
 
+    public static final byte BGP_FLOW_SPEC_LEN_MASK = 0x30;
+    public static final byte BGP_FLOW_SPEC_END_OF_LIST_MASK = (byte) 0x80;
 }
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