Fully Bideniable Interactive Encryption
To date, only partial results were known: either deniability against coercing only the sender, or against coercing only the receiver [Sahai-Waters, STOC 14] or schemes satisfying weaker notions of deniability [ONeil et al., Crypto 11]. In this paper we present the first fully bideniable interactive encryption scheme, thus resolving the 20-years-old open problem. Our scheme also satisfies an additional, incomparable to standard deniability, property called off-the-record deniability, which we introduce in this paper. This property guarantees that, even if the sender claims that one plaintext was used and the receiver claims a different one, the adversary has no way of figuring out who is lying – the sender, the receiver, or both. We assume subexponential indistinguishability obfuscation (iO) and one way functions.
Source: eprint.iacr.org