CCA1-secure somewhat homomorphic encryption

This paper proposes the combination of homomorphic encryption and verifiable computation to avoid key recovery attacks and achieve CCA1-secure constructions of Somewhat Homomorphic Encryption (SHE) schemes described in the literature. We also provide concrete parameters, based on the best-attack analysis, concluding that the AGCD [van Dijk et al. 2010] family of SHE schemes may be the best implementation choice under certain circumstances.