Robust Combiners for Software Hardening

Practical software hardening schemes, as well as practical encryption schemes, e.g., AES, are heuristic and do not rely on provable security. One technique to enhance security is

robust combiners

. An algorithm

C

is a robust combiner for specification

S

, e.g., privacy, if for any two implementations

X

and

Y

, of a cryptographic scheme, the combined scheme

C(X, Y )

satisfies

S

provided

either

X or Y

satisfy

S

.

We present the first robust combiners for software hardening, specifically for

White-Box Remote Program Execution (WBRPE)

[10].

WBRPE

is a software hardening technique that is employed to protect execution of programs in remote, hostile environment.

WBRPE

provides a software only platform allowing secure execution of programs on untrusted, remote hosts, ensuring privacy of the program, and of the inputs to the program, as well as privacy and integrity of the result of the computation.

Robust combiners are particularly important for software hardening, where there is no standard whose security is established. In addition, robust combiners for software hardening are interesting from software engineering perspective since they introduce new techniques of reductions and code manipulation.