Garbling schemes allow to construct two-party function evaluation with security against cheating parties (SFE). To achieve this goal, one party (the Garbler) sends multiple encodings of a circuit (called Garbled Circuits) to the other party (the Evaluator) and opens a subset of these encodings, showing that they were generated honestly. For the remaining garbled circuits, the garbler sends encodings of the inputs. This allows the evaluator to compute the result of function, while the encoding ensures that no other information beyond the output is revealed. To achieve active security against a malicious adversary, the garbler in current protocols has to send O(s) circuits (where s is the statistical security parameter). In this work we show that, for a certain class of circuits, one can reduce this overhead. We consider circuits where sub-circuits depend only on one party’s input. Intuitively, one can evaluate these sub-circuits using only one circuit and privacy-free garbling. This has applications to e.g. input validation in SFE and allows to construct more efficient SFE protocols in such cases. We additionally show how to integrate our solution with the SFE protocol of , thus reducing the overhead even further.
|Title of host publication||Security and Cryptography for Networks - 10th International Conference, SCN 2016, Proceedings|
|Editors||Roberto De Prisco, Vassilis Zikas|
|Number of pages||18|
|State||Published - 2016|
|Event||10th International Conference on Security and Cryptography for Networks, SCN 2016 - Amalfi, Italy|
Duration: 31 Aug 2016 → 2 Sep 2016
|Name||Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics)|
|Conference||10th International Conference on Security and Cryptography for Networks, SCN 2016|
|Period||31/08/16 → 2/09/16|
Bibliographical noteFunding Information:
C. Baum—Supported by The Danish National Research Foundation and The National Science Foundation of China (under the grant 61061130540) for the Sino-Danish Center for the Theory of Interactive Computation, within which part of this work was performed; by the CFEM research center (supported by the Danish Strategic Research Council) within which part of this work was performed; and by the Advanced ERC grant MPCPRO.
© Springer International Publishing Switzerland 2016.