Concrete Security Against Adversaries with Quantum Superposition Access to Encryption and Decryption Oracles
This work addresses security for encryption schemes in quantum computing contexts, representing an incremental advancement by extending prior quantum access models to full superposition.
The paper tackles the problem of defining and achieving indistinguishability under chosen plaintext and chosen ciphertext attacks for symmetric encryption schemes against adversaries with full quantum superposition access to encryption and decryption oracles, providing constructions that meet these security notions in a concrete security framework.
In 2013, Boneh and Zhandry introduced the notion of indistinguishability (IND) in chosen plaintext (CPA) and chosen ciphertext (CCA) attacks by a quantum adversary which is given superposition access to an oracle for encryption and decryption queries but is restricted to classical queries in the challenge phase. In this paper we define IND-CPA and IND-CCA notions for symmetric encryption schemes where the adversary has full quantum superposition access to the oracle, and give constructions that achieve these security notions. Our results are formulated in the concrete security framework.