IACR News item: 17 May 2021
Charalampos Papamanthou, Cong Zhang, Hong-Sheng Zhou
ePrint Report
Digital signatures have been widely used as building blocks for constructing complex cryptosystems.
To facilitate the security analysis of a complex system, we expect the underlying building blocks to achieve desirable composability.
Notably, Canetti (FOCS 2001) and then Maurer et al (TCC 2004) propose analysis frameworks, the Universal Composability framework for cryptographic protocols, and the indifferentiability framework for cryptographic objects.
In this paper, we develop a “lifting strategy”, which allows us to compile multiple existing practical signature schemes using cyclic group (e.g., Schnorr, Boneh-Boyen), to achieve a very stringent security guarantee, in an idealized model of the generic (bilinear) group, without introducing much extra efficiency loss. What's more interesting is that, in our design, even the involved idealized model does not exist, our compiled construction will still be able to achieve the classical notion of unforgeability.
To achieve both indifferentiability and good efficiency, we develop new techniques in generic (bilinear) group model.
In this paper, we develop a “lifting strategy”, which allows us to compile multiple existing practical signature schemes using cyclic group (e.g., Schnorr, Boneh-Boyen), to achieve a very stringent security guarantee, in an idealized model of the generic (bilinear) group, without introducing much extra efficiency loss. What's more interesting is that, in our design, even the involved idealized model does not exist, our compiled construction will still be able to achieve the classical notion of unforgeability.
To achieve both indifferentiability and good efficiency, we develop new techniques in generic (bilinear) group model.
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