NIST LWC Hardware Reference Design of Ascon v1.2

• Hardware Design Group: Institute of Applied Information Processing and Communications, Graz, Austria
• Primary Hardware Designers:
  • Robert Primas (https://rprimas.github.io, rprimas 'at' proton.me)
• LWC candidate: Ascon
• LWC Hardware API version: 1.2.0

Ascon is a family of authenticated encryption and hashing algorithms designed to be lightweight and easy to implement, even with added countermeasures against side-channel attacks. Ascon has been selected as new standard for lightweight cryptography in the NIST Lightweight Cryptography competition (2019–2023). Ascon has also been selected as the primary choice for lightweight authenticated encryption in the final portfolio of the CAESAR competition (2014-2019).

This code base contains a VHDL implementation of Ascon. I recently also published a Verilog implementation of Ascon that uses a similar but simpler crypto core interface and has a considerably reduced code size. Also, the Verilog implementation comes with a more permissive CC0 license. The Verilog implementation is available here.

Available Variants

• v1 : ascon128v12 + asconhashv12, 32-bit interface, 1 permutation round per clock cycle
• v1_8bit : ascon128v12 + asconhashv12, 8-bit interface, 1 permutation round per clock cycle
• v1_16bit : ascon128v12 + asconhashv12, 16-bit interface, 1 permutation round per clock cycle
• v2 : ascon128av12 + asconhashav12, 32-bit interface, 1 permutation round per clock cycle
• v3 : ascon128v12 + asconhashv12, 32-bit interface, 2 permutation rounds per clock cycle
• v4 : ascon128av12 + asconhashav12, 32-bit interface, 2 permutation rounds per clock cycle
• v5 : ascon128v12 + asconhashv12, 32-bit interface, 3 permutation rounds per clock cycle
• v6 : ascon128av12 + asconhashav12, 32-bit interface, 4 permutation rounds per clock cycle

Folders

• hardware: HDL sources and testbench scripts.
• software: Software reference implementation and Known-Answer-Test (KAT) generation scripts.

Quick Start

• Install the GHDL open-source VHDL simulator (tested with version 0.37 and 1.0 and 2.0):
  • sudo apt install ghdl
• Execute VHDL testbench for v1 (or other variants):
  • cd hardware/ascon_lwc
  • make v1

Generating new Testvectors from Software

• Install testvector generation scripts:
  • pip install software/cryptotvgen
• Compile Ascon software reference implementations:
  • cryptotvgen --prepare_libs --candidates_dir=software/ascon_ref
• Locate testvector generation scripts:
  • cd software/cryptotvgen/examples
• Run (and optionally modify) a testvector generation script:
  • python genkat_v1.py
• Replace existing testvectors (KAT) of v1 with the newly generated ones:
  • mv testvectors/v1_32 testvectors/v1
  • rm -r ../../../hardware/ascon_lwc/KAT/v1
  • mv testvectors/v1 ../../../hardware/ascon_lwc/KAT
• Execute VHDL testbench for v1:
  • cd ../../../hardware/ascon_lwc
  • make v1

Acknowledgements

This code base is based on version 1.2.0 of the LWC Hardware API Development Package that was mainly developed by the Cryptographic Engineering Research Group (CERG) at George Mason University (GMU).

Parts of the development package have been developed by the Department of Electrical and Computer Engineering (ECE) at Technical University of Munich (TUM).

The Ascon-specific modifications have been developed by the Institute of Applied Information Processing and Communications (IAIK) at Graz University of Technology (TUG).