In this work, we extend the above two impossibility results for general VBB obfuscation in idealized models. In particular we prove the following two results both assuming the existence of trapdoor permutations:
* There is no general VBB obfuscation in the generic group model of Shoup (Eurocrypt'97) for any abelien group. By applying our techniques to the setting of Pass and Shelat we extend their result to any (even non-commutative) finite ring.
* There is no general VBB obfuscation in the random trapdoor permutation oracle model. Note that as opposed to the random oracle which is an idealized primitive for symmetric primitives, random trapdoor permutation is an idealized public-key primitive.Category / Keywords: Virtual Black-Box Obfuscation, Idealized Models, Graded Encoding, Random Oracles Date: received 25 Jun 2015, last revised 30 Jun 2016 Contact author: mahmoody at gmail com Available format(s): PDF | BibTeX Citation Version: 20160630:195304 (All versions of this report) Short URL: ia.cr/2015/632 Discussion forum: Show discussion | Start new discussion