The work of Barak, Goldreich, Impagliazzo, Rudich, Sahai, Vadhan, and Yang (CRYPTO'01 and Journal of ACM 59(2)) shows that, assuming indistinguishability obfuscation (iO), such watermarking is impossible if the marked program C~ evaluates the original program with perfect correctness. In this work we show that, assuming iO, such watermarking is possible if the marked program C~ is allowed to err with even a negligible probability, which would be undetectable to the user.
Our watermarking schemes are public key, meaning that we use a secret marking key to embed marks in programs, and a public detection key that allows anyone to detect marks in programs. Our schemes are secure against chosen program attacks where the adversary is given oracle access to the marking functionality. We emphasize that our security notion of watermark non-removability considers arbitrary adversarial strategies to modify the marked program, in contrast to the prior works (Nishimaki, EUROCRYPT '13).Category / Keywords: public-key cryptography / watermarking, indistingushability obfuscation, puncturable PRFs Original Publication (with major differences): STOC 2016 Date: received 10 Nov 2015, last revised 8 Feb 2016 Contact author: nishimaki ryo at lab ntt co jp Available format(s): PDF | BibTeX Citation Note: Added acknowledgements Version: 20160208:114745 (All versions of this report) Short URL: ia.cr/2015/1096 Discussion forum: Show discussion | Start new discussion