Reza Reyhanitabar, Antoon Purnal, Elena Andreeva, Arnab Roy, Virginie Lallemand, Damian Vizár, IMEC (IMEC), Catholic University of Leuven - Katholieke Universiteit Leuven (KU Leuven), Cryptology, arithmetic : algebraic methods for better algorithms (CARAMBA), Department of Algorithms, Computation, Image and Geometry (LORIA - ALGO), Laboratoire Lorrain de Recherche en Informatique et ses Applications (LORIA), Centre National de la Recherche Scientifique (CNRS)-Université de Lorraine (UL)-Institut National de Recherche en Informatique et en Automatique (Inria)-Centre National de la Recherche Scientifique (CNRS)-Université de Lorraine (UL)-Institut National de Recherche en Informatique et en Automatique (Inria)-Laboratoire Lorrain de Recherche en Informatique et ses Applications (LORIA), Centre National de la Recherche Scientifique (CNRS)-Université de Lorraine (UL)-Institut National de Recherche en Informatique et en Automatique (Inria)-Centre National de la Recherche Scientifique (CNRS)-Université de Lorraine (UL)-Institut National de Recherche en Informatique et en Automatique (Inria)-Inria Nancy - Grand Est, Institut National de Recherche en Informatique et en Automatique (Inria), TE Connectivity Ltd, University of Bristol [Bristol], Centre Suisse d'Electronique et de Microtechnique SA [Neuchatel] (CSEM), Centre Suisse d'Electronique et Microtechnique SA (CSEM), Elena Andreeva was supported in part by the Research Council KU Leuven C1 on Security and Privacy for Cyber-Physical Systems and the Internet of Things with contract number C16/15/058 and by the Research Council KU Leuven, C16/18/004, through the EIT Health RAMSES project, through the IF/C1 on New Block Cipher Structures, and through the NIST project. In addition, this work was supported by the European Commission through the Horizon 2020 research and innovation programme under grant agreement H2020-DS-2014-653497 PANORAMIX and through the grant H2020-DS-SC7-2016-740507 Eunity. The work is supported in part by funding from imec of the Flemish Government. Antoon Purnal is supported by the Horizon 2020 research and innovation programme under Cathedral ERC Advanced Grant 695305. Reza Reyhanitabar’s work on this project was initiated when he was with KU Leuven and supported by an EU H2020-MSCA-IF fellowship under grant ID 708815, continued and submitted when he was with Elektrobit Automotive GmbH, and revised while he is now with TE Connectivity. Arnab Roy is supported by the EPSRC grant No. EPSRC EP/N011635/1., European Project: 708815,H2020,H2020-MSCA-IF-2015,POMEGRANATE(2017), European Project: 695305,Cathedral(2016), European Project: 653497,H2020,H2020-DS-2014-1,PANORAMIX(2015), European Project: 740507,EUNITY(2017), Inria Nancy - Grand Est, Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria)-Department of Algorithms, Computation, Image and Geometry (LORIA - ALGO), Institut National de Recherche en Informatique et en Automatique (Inria)-Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche en Informatique et en Automatique (Inria)-Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS)-Laboratoire Lorrain de Recherche en Informatique et ses Applications (LORIA), Institut National de Recherche en Informatique et en Automatique (Inria)-Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS)-Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS), Galbraith, SD, and Moriai, S
Highly efficient encryption and authentication of short messages is an essential requirement for enabling security in constrained scenarios such as the CAN FD in automotive systems (max. message size 64 bytes), massive IoT, critical communication domains of 5G, and Narrowband IoT, to mention a few. In addition, one of the NIST lightweight cryptography project requirements is that AEAD schemes shall be “optimized to be efficient for short messages (e.g., as short as 8 bytes)”. In this work we introduce and formalize a novel primitive in symmetric cryptography called forkcipher. A forkcipher is a keyed primitive expanding a fixed-lenght input to a fixed-length output. We define its security as indistinguishability under a chosen ciphertext attack (for n-bit inputs to 2n-bit outputs). We give a generic construction validation via the new iterate-fork-iterate design paradigm. We then propose 𝖥𝗈𝗋𝗄𝖲𝗄𝗂𝗇𝗇𝗒 as a concrete forkcipher instance with a public tweak and based on SKINNY: a tweakable lightweight cipher following the TWEAKEY framework. We conduct extensive cryptanalysis of 𝖥𝗈𝗋𝗄𝖲𝗄𝗂𝗇𝗇𝗒 against classical and structure-specific attacks. We demonstrate the applicability of forkciphers by designing three new provably-secure nonce-based AEAD modes which offer performance and security tradeoffs and are optimized for efficiency of very short messages. Considering a reference block size of 16 bytes, and ignoring possible hardware optimizations, our new AEAD schemes beat the best SKINNY-based AEAD modes. More generally, we show forkciphers are suited for lightweight applications dealing with predominantly short messages, while at the same time allowing handling arbitrary messages sizes. Furthermore, our hardware implementation results show that when we exploit the inherent parallelism of 𝖥𝗈𝗋𝗄𝖲𝗄𝗂𝗇𝗇𝗒 we achieve the best performance when directly compared with the most efficient mode instantiated with SKINNY. ispartof: pages:153-182 ispartof: International Conference on the Theory and Application of Cryptology and Information Security vol:11922 pages:153-182 ispartof: ASIACRYPT 2019 location:Kobe, Japan date:8 Dec - 12 Dec 2019 status: published