CHQS: Publicly Verifiable Homomorphic Signatures Beyond the Linear Case
Lucas Schabhüser, Denis Butin, Johannes Buchmann
Sensitive data is often outsourced to cloud servers, with the server performing computation on the data. Computational correctness must be efficiently verifiable by a third party while the input data remains confidential. This paper introduces CHQS, a homomorphic signature scheme from bilinear groups fulfilling these requirements. CHQS is the first such scheme to be both context hiding and publicly verifiable for arithmetic circuits of degree two. It also achieves amortized efficiency: after a precomputation, verification can be faster than the evaluation of the circuit itself.
Place and Date
Tokyo, Japan, Sep 25-27, 2018