Signature Schemes with Bounded Leakage Resilience

A leakage-resilient cryptosystem remains secure even if arbitrary, but bounded, information about the secret key (or possibly other internal state information) is leaked to an adversary. Denote the length of the secret key by n. We show a signature scheme tolerating (optimal) leakage of up to n − nǫ bits of information about the secret key, and a more efficient one-time signature scheme that tolerates leakage of (1 4 −ǫ)·n bits of information about the signer’s entire state. The latter construction extends to give a leakage-resilient t-time signature scheme. All these constructions are in the standard model under general assumptions.

• Type: Conference
• Year: 2009
• Where: ASIACRYPT
• Authors: Jonathan Katz, Vinod Vaikuntanathan
• Keywords: ASIACRYPT 2009, Cryptology, One-time Signature Scheme, Secret Key, Signature Scheme