XTOLS: Cross-Tier Oracle Label Security

SELINKS allows cross-tier security enforcement between the application tier and the database tier by compiling policy functions and database queries into User-Defined Functions (UDFs) and SQL queries. Unfortunately, this kind of enforcement is restricted to the policies written within SELINKS framework; and therefore, it does not take into account the existing policies in the database. Furthermore, the data in the database may be vulnerable to unauthorized access because the database does not necessarily enforce the security policies intended by the application.