worst-case costs for dynamic data element security decisions
The major shortcomings of file security systems which control access decisions at source code translation time are enumerated. An experimental implementation of a system which uses modified operating system I/O routines to distinguish data dependent and independent accesses at execution time is then discussed. CPU overhead costs for different file access restrictions are examined. Preliminary results indicate that cost feasible methods of dynamic selective security may be possible under current operating systems.
costs security privacy data-dependent