We introduce Free Hash, a new approach to generating Garbled Circuit (GC) hash at no extra cost during GC generation. This is in contrast with state-of-the-art approaches, which hash GCs at computational cost of up to 6× of GC generation. GC hashing is at the core of the cut-and-choose technique of GC-based secure function evaluation (SFE). Our main idea is to intertwine hash generation/verification with GC generation and evaluation. While we allow an adversary to generate a GC GC whose hash collides with an honestly generated GC, such a GC w.h.p. will fail evaluation and cheating will be discovered. Our GC hash is simply a (slightly modified) XOR of all the gate table rows of GC. It is compatible with Free XOR and half-gates garbling, and can be made to work with many cut-and-choose SFE protocols. With today’s network speeds being not far behind hardware-assisted fixed-key garbling throughput, eliminating the GC hashing cost will significantly improve SFE performance. Our estimates show substantial cost reduction in typical settings, and up to factor 6 in specialized applications relying on GC hashes. We implemented GC hashing algorithm and report on its performance.
CITATION STYLE
Fan, X., Ganesh, C., & Kolesnikov, V. (2017). Hashing garbled circuits for free. In Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics) (Vol. 10212 LNCS, pp. 456–485). Springer Verlag. https://doi.org/10.1007/978-3-319-56617-7_16
Mendeley helps you to discover research relevant for your work.