Cryptology ePrint Archive: Report 2021/439

Recovering the Key from the Internal State of Grain-128AEAD

Donghoon Chang and Meltem Sonmez Turan

Abstract: Grain-128AEAD is one of the second-round candidates of the NIST lightweight cryptography standardization process. There is an existing body of third-party analysis on the earlier versions of the Grain family that provide insights on the security of Grain-128AEAD. Different from the earlier versions, Grain-128AEAD reintroduces the key into the internal state during the initialization. The designers claim that internal state recovery no longer results in key recovery, due to this change. In this paper, we analyze this claim under different scenarios.

Category / Keywords: secret-key cryptography / Grain-128AEAD and lightweight cryptography and key recovery

Date: received 3 Apr 2021

Contact author: meltem turan at nist gov, pointchang@gmail com

Available format(s): PDF | BibTeX Citation

Version: 20210406:072757 (All versions of this report)

Short URL: ia.cr/2021/439