## CryptoDB

### Paper: Collusion Resistant Watermarking Schemes for Cryptographic Functionalities

Authors: Rupeng Yang Man Ho Au Junzuo Lai Qiuliang Xu Zuoxia Yu DOI: 10.1007/978-3-030-34578-5_14 Search ePrint Search Google A cryptographic watermarking scheme embeds a message into a program while preserving its functionality. Recently, a number of watermarking schemes have been proposed, which are proven secure in the sense that given one marked program, any attempt to remove the embedded message will substantially change its functionality.In this paper, we formally initiate the study of collusion attacks for watermarking schemes, where the attacker’s goal is to remove the embedded messages given multiple copies of the same program, each with a different embedded message. This is motivated by practical scenarios, where a program may be marked multiple times with different messages.The results of this work are twofold. First, we examine existing cryptographic watermarking schemes and observe that all of them are vulnerable to collusion attacks. Second, we construct collusion resistant watermarking schemes for various cryptographic functionalities (e.g., pseudorandom function evaluation, decryption, etc.). To achieve our second result, we present a new primitive called puncturable functional encryption scheme, which may be of independent interest.
##### BibTeX
@article{asiacrypt-2019-30021,
title={Collusion Resistant Watermarking Schemes for Cryptographic Functionalities},
booktitle={Advances in Cryptology – ASIACRYPT 2019},
series={Advances in Cryptology – ASIACRYPT 2019},
publisher={Springer},
volume={11921},
pages={371-398},
doi={10.1007/978-3-030-34578-5_14},
author={Rupeng Yang and Man Ho Au and Junzuo Lai and Qiuliang Xu and Zuoxia Yu},
year=2019
}