Copy-Protection from Unclonable Puncturable Obfuscation
Amit Behera
Abstract:
Quantum copy-protection is a functionality-preserving compiler that transforms a classical program into an unclonable quantum program. This primitive has emerged as a foundational topic in quantum cryptography, with significant recent developments. However, characterizing the functionalities that can be copy-protected is still an active and ongoing research direction. In this talk, I will present new feasibility results of copy-protection based on a new abstraction called Unclonable Puncturable Obfuscation (UPO). In particular, using this framework, we establish the plain-model existence of copy-protection for various classes of functionalities, including puncturable cryptographic functionalities and subclasses of evasive functionalities, under well-studied assumptions, namely, the existence of indistinguishability obfuscation and the Learning With Errors (LWE) assumption. I will also discuss new and stronger security definitions of copy-protection that are satisfied by our constructions, highlighting the conceptual advantages of building copy-protection based on UPO. At the heart of these results lies a plain-model instantiation of UPO, obtained by leveraging recently introduced techniques from [Kitagawa and Yamakawa, TCC'25], which may be of independent interest beyond copy-protection.
The talk is based on joint work with Prabhanjan Ananth, Zikuan Huang, Fuyuki Kitagawa, and Takashi Yamakawa.
Bio:
Amit Behera is a Postdoctoral fellow at NTT Research, hosted by Dr. Vipul Goyal. Previously, he was a Doctoral student in Computer Science at Ben-Gurion University under the supervision of Prof. Or Sattath and Prof. Zvika Brakerski. He is broadly interested in quantum cryptography and its connections to various aspects of complexity theory.