We make progress toward these problems by ruling out all fully-blackbox constructions of
-- 1-seed circular-secure public-key bit encryption from CPA-secure public-key encryption;
-- t-seed circular-secure public-key encryption from (t-1)-seed circular-secure public-key encryption, for any $t \geq 2$.
Informally, seed-circular security is a variant of the circular security notion in which the seed of the key-generation algorithm, instead of the secret key, is encrypted. We also show how to extend our first result to rule out a large and non-trivial class of constructions of 1-circular-secure bit encryption, which we dub key-isolating constructions.
Our separation model follows that of Gertner, Malkin and Reingold (FOCS’01), which is a weaker separation model than that of Impagliazzo and Rudich.Category / Keywords: foundations / Black-box separations, circular security Original Publication (with minor differences): IACR-EUROCRYPT-2017 Date: received 15 Feb 2017, last revised 9 Mar 2017 Contact author: m hajiabadi at ucl ac uk Available format(s): PDF | BibTeX Citation Note: Fixed some typos. Version: 20170309:174212 (All versions of this report) Short URL: ia.cr/2017/146 Discussion forum: Show discussion | Start new discussion