1. A method, in a data processing system, for authorizing information flows between devices of the data processing system, the method comprising: generating a hash key based on an information object; performing a lookup operation in a hash table based on the hash key; determining if an entry in the hash table at an index corresponding to the hash key identifies a labelset for the information object; storing a labelset, identifying a sensitivity of the information object, in the entry at the index corresponding to the hash key for the information object if a labelset for the information object is not identified in the entry in the hash table; and authorizing information flows involving the information object based on a lookup of the labelset associated with the information object in the hash table.