## Appeared in TCC-2010. Efficiency Preserving Transformations for Concurrent Non-Malleable Zero Knowledge

### BibTeX

@MISC{Ostrovsky_appearedin,

author = {Rafail Ostrovsky and Omkant P and Ivan Visconti},

title = {Appeared in TCC-2010. Efficiency Preserving Transformations for Concurrent Non-Malleable Zero Knowledge},

year = {}

}

### OpenURL

### Abstract

Abstract. Ever since the invention of Zero-Knowledge by Goldwasser, Micali, and Rackoff [1], Zero-Knowledge has become a central building block in cryptography- with numerous applications, ranging from electronic cash to digital signatures. The properties of Zero-Knowledge range from the most simple (and not particularly useful in practice) requirements, such as honest-verifier zero-knowledge to the most demanding (and most useful in applications) such as non-malleable and concurrent zero-knowledge. In this paper, we study the complexity of efficient zero-knowledge reductions, from the first type to the second type. More precisely, under a standard complexity assumption (ddh), on input a public-coin honest-verifier statistical zero knowledge argument of knowledge π ′ for a language L we show a compiler that produces an argument system π for L that is concurrent non-malleable zero-knowledge (under non-adaptive inputs – which is the best one can hope to achieve [2, 3]). If κ is the security parameter, the overhead of our compiler is as follows: