SecureScala: Scala embedding of secure computations

Cloud computing offers an attractive and cost-efficient computing platform and hence it has been widely adopted by the industry and the government. At the same time, cloud computing poses a serious security challenge because sensitive data must often be outsourced to third party entities that can access the data and perform computations on them. Partial homomorphic encryption is promising for secure computation, since it allows programs to be executed over encrypted data. Despite advances in cryptographic techniques have improved the expressivity of such programs, integration with mainstream languages has seen little progress. To this end, we present SecureScala, a domain-specific language in Scala that allows expressing secure programs without requiring any cryptographic knowledge. SecureScala is based on a novel combination of free monads and free applicative functors and supports parallel execution and static analyzability. We evaluate our approach through several case studies, demonstrate its expressivity, and show that it incurs in limited performance overhead.