This repository accompanies the paper Efficient Multiplication of Somewhat Small Integers using Number-Theoretic Transforms available at https://eprint.iacr.org/2022/439.

Authors:

• Hanno Becker <hanno.becker@arm.com>
• Vincent Hwang <vincentvbh7@gmail.com>
• Matthias J. Kannwischer <matthias@kannwischer.eu>
• Lorenz Panny <lorenz@yx7.cc>
• Bo-Yin Yang <by@crypto.tw>

It contains the Cortex-M3 implementation of the NTT-based integer multiplier, the schoolbook multiplication (using finely-integrated operand scanning), and the Hensel lifting. The Cortex-M55 code will be published at a later point here.

Clone the code including the submodules using

git clone --recurse-submodules https://github.com/ntt-int-mul/ntt-int-mul-m3

Hardware

We use the Nucleo STM32F207ZG.

Software

For building the software, we use the arm-none-eabi-gcc toolchain. For flashing binaries, we use st-link.

Structure

• intmulm3 contains the NTT-based integer multiplier. Refer to the README.md
• schoolbookm3 contains the schoolbook multiplier for reference. Refer to the README.md
• hensel-lifting-m3 contains Hensel lifting. Refer to the README.md

License

All files in this repository are published under a CC0 copyright-waiver.