A Practical Leakage-Resilient Signature Scheme in the Generic Group Model

We propose a leakage-resilient signature scheme in the continual leakage model that is based on a well-known identity-based encryption scheme by Boneh and Boyen (Eurocrypt 2004). The proposed signature scheme is the most efficient among the existing schemes that allow for continual leakage. Its efficiency is close to that of non leakage-resilient pairing-based signature schemes. It tolerates leakage of almost half of the bits of the secret key at every new signature invocation. We prove the security of the new scheme in the generic bilinear group model.