@article {3201, title = {Post-Quantum Security of the (Tweakable) FX Construction, and Applications}, year = {2022}, month = {8/29/2022}, abstract = {

The FX construction provides a way to increase the effective key length of a block cipher E. We prove security of a tweakable version of the FX construction in the post-quantum setting, i.e., against a quantum attacker given only classical access to the secretly keyed construction while retaining quantum access to E, a setting that seems to be the most relevant one for real-world applications. We then use our results to prove post-quantum security\—in the same model\—of the (plain) FX construction, Elephant (a finalist of NIST\&$\#$39;s lightweight cryptography standardization effort), and Chaskey (an ISO-standardized lightweight MAC

}, url = {https://eprint.iacr.org/2022/1097}, author = {Gorjan Alagic and Chen Bai and Jonathan Katz and Christian Majenz and Patrick Struck} }