International Association for Cryptologic Research

International Association
for Cryptologic Research

IACR News item: 19 November 2020

Michael Kounavis, David Durham, Sergej Deutsch, Krystian Matusiewicz, David Wheeler
ePrint Report ePrint Report
We present MAGIC, a mode for authenticated encryption that simultaneously supports encryption, message authentication and error correction, all with the same code. In MAGIC, the same code employed for cryptographic integrity is also the parity used for error correction. To correct errors, MAGIC employs the Galois Hash transformation, which due to its bit linearity can perform corrections in a similar way as other codes do (e.g., Reed Solomon). To provide a cryptographically strong MAC, MAGIC encrypts the output of the Galois Hash using a secret key. To analyze the security of this construction we adapt the definition of the MAC adversary so that it is applicable to systems that combine message authentication with error correction. We demonstrate that MAGIC offers security in the order of O(2^(N/2)) with N being the tag size.

Additional news items may be found on the IACR news page.