Paper 2014/517

On the Connection between Leakage Tolerance and Adaptive Security

Jesper Buus Nielsen, Daniele Venturi, and Angela Zottarel

Abstract

We revisit the context of leakage-tolerant interactive protocols as defined by Bitanski, Canetti and Halevi (TCC 2012). Our contributions can be summarized as follows: \begin{itemize} \item For the purpose of secure message transmission, any encryption protocol with message space $$ and secret key space $$ tolerating poly-logarithmic leakage on the secret state of the receiver must satisfy $$, for every $$, and if $$, then the scheme must use a fresh key pair to encrypt each message. \item More generally, we show that any $$ party protocol tolerates leakage of $$ bits from one party at the end of the protocol execution, \emph{if and only if} the protocol has passive adaptive security against an adaptive corruption of one party at the end of the protocol execution. This shows that as soon as a little leakage is tolerated, one needs full adaptive security. \end{itemize} All our results can be based on the only assumption that collision-resistant function ensembles exist.

Note: Slightly revised version. Updated bibliography.