Python implementation of Ascon

This is a Python3 implementation of Ascon v1.2, an authenticated cipher and hash function.

https://github.com/meichlseder/pyascon

Ascon

Ascon is a family of authenticated encryption (AEAD) and hashing algorithms designed to be lightweight and easy to implement, even with added countermeasures against side-channel attacks. It was designed by a team of cryptographers from Graz University of Technology, Infineon Technologies, and Radboud University: Christoph Dobraunig, Maria Eichlseder, Florian Mendel, and Martin Schläffer.

Ascon has been selected as the standard for lightweight cryptography in the NIST Lightweight Cryptography competition (2019–2023) and as the primary choice for lightweight authenticated encryption in the final portfolio of the CAESAR competition (2014–2019).

Find more information, including the specification and more implementations here:

https://ascon.iaik.tugraz.at/

Algorithms

This is a simple reference implementation of Ascon v1.2 as submitted to the NIST LWC competition that includes

• Authenticated encryption ascon.encrypt(key, nonce, associateddata, plaintext, variant="Ascon-128") (and similarly decrypt) with the following 3 family members:

  • Ascon-128
  • Ascon-128a
  • Ascon-80pq

• Hashing algorithms ascon.hash(message, variant="Ascon-Hash", hashlength=32) including 4 hash function variants with fixed 256-bit (Hash) or variable (Xof) output lengths:

  • Ascon-Hash
  • Ascon-Hasha
  • Ascon-Xof
  • Ascon-Xofa

• Message authentication codes ascon.mac(key, message, variant="Ascon-Mac", taglength=16) including 5 MAC variants (from https://eprint.iacr.org/2021/1574, not part of the LWC proposal) with fixed 128-bit (Mac) or variable (Prf) output lengths, including a variant for short messages of up to 128 bits (PrfShort).

  • Ascon-Mac
  • Ascon-Maca
  • Ascon-Prf
  • Ascon-Prfa
  • Ascon-PrfShort