A New Way to Think About Secure Computation: Language-based Secure Computation

Assume two parties, Alice and Bob, want to compute a joint function, but they want to keep their inputs private. This problem setting and its solutions are known as secure computation. General solutions to secure computation require the construction of a binary circuit for the function to be computed. This paper proposes the concept of languagebased secure computation. Instead of constructing a binary circuit program code is directly translated into a secure computation protocol. This concept is compared to the approaches for language-based informationflow security and many connections between the two approaches are identified. The major challenge in this translation is the secure translation of the program’s control-flow without leaking private information via a timing channel. The paper presents a method for translating an if statement with a secret branching condition that may not be known to any party. Furthermore, that protocol can be optimized using trusted computing, such that the overall performance of a program executed as a secure computation protocol can be greatly improved.