Title
Constructing Non-malleable Commitments: A Black-Box Approach
Abstract
We propose the first black-box construction of non-malleable commitments according to the standard notion of non-malleability with respect to commitment. Our construction additionally only requires a constant number of rounds and is based only on (black-box use of) one-way functions. Prior to our work, no black-box construction of non-malleable commitments was known (except for relaxed notions of security) in any (polynomial) number of rounds based on any cryptographic assumption. This closes the wide gap existent between black-box and non-black-box constructions for the problem of non-malleable commitments. Our construction relies on (and can be seen as a generalization of) the recent non-malleable commitment scheme of Goyal (STOC 2011). We also show how to get black-box constructions for a host of other cryptographic primitives. We extend our construction to get constant-round concurrent non-malleable commitments, constant-round multi-party coin tossing, and non-malleable statistically hiding commitments (satisfying the notion of non-malleability with respect to opening). All of the mentioned results make only a black-box use of one-way functions. Our primary technical contribution is a novel way of implementing the proof of consistency typically required in the constructions of non-malleable commitments (and other related primitives). We do this by relying on ideas from the ``zero-knowledge from secure multi-party computation" paradigm of Ishai, Kushilevitz, Ostrovsky, and Sahai (STOC 2007). We extend in a novel way this ``computation in the head" paradigm (which can be though of as bringing powerful error-correcting codes into purely computational setting). To construct a non-malleable commitment scheme, we apply our computation in the head techniques to the recent (constant-round) construction of Goyal. Along the way, we also present a simplification of the construction of Goyal where a part of the protocol is implemented in an information theoretic manner. Su- h a simplification is crucial for getting a black-box construction. This is done by making use of pair wise-independent hash functions and strong randomness extractors. We show that our techniques have multiple applications, as elaborated in the paper. Hence, we believe our techniques might be useful in other settings in future.
Year
DOI
Venue
2012
10.1109/FOCS.2012.47
Foundations of Computer Science
Keywords
Field
DocType
black-box approach,one-way function,non-black-box construction,black-box use,secure multi-party computation,constant-round concurrent non-malleable commitment,constant-round multi-party coin,non-malleable commitment,black-box construction,constructing non-malleable commitments,recent non-malleable commitment scheme,non-malleable commitment scheme,statistical analysis,cryptography,information theory
Information theory,Black box (phreaking),Combinatorics,Computer science,Cryptography,Commitment scheme,Theoretical computer science,Cryptographic primitive,Hash function,Coin flipping,Randomness
Conference
ISSN
ISBN
Citations 
0272-5428
978-1-4673-4383-1
36
PageRank 
References 
Authors
0.87
26
4
Name
Order
Citations
PageRank
Vipul Goyal12859129.53
Chen-Kuei Lee2360.87
Rafail Ostrovsky38743588.15
Ivan Visconti461240.30