Geonhee Cho  Myungsuk Kim  Jihong Kim

10.5626/JOK.2022.49.2.120

3D NAND flash plausible deniability hidden volume mechanism deniable storage

Traditional encryption cannot defend against coercive attackers who compel the user to hand over decryption keys as it cannot hide the existence of the ciphertext. To solve this problem, there have been studies on a deniable storage solution that applies plausible deniability, a characteristic that allows the user to deny the existence of sensitive data, to a storage device. The hidden volume mechanism is being used in various deniable storage solutions due to its relatively low-performance overhead compared to other mechanisms, and has recently evolved to defend against multiple-snapshot attacks. However, the existing hidden volume mechanism fundamentally requires a dummy random data pool to hide the ciphertext. Due to the existence of dummy random data stored in the storage device, the plausible deniability characteristic is exposed, which can reveal the intention to hide the data. This study proposes a flash chip-level access control command set that simultaneously supports data sanitization and plausible deniability, and using this, we propose a hidden volume-based deniable storage solution that supports plausible deniability characteristics without dummy random data.