This repository implements the signature scheme Falcon (https://falcon-sign.info/). Falcon stands for FAst Fourier Lattice-based COmpact signatures over NTRU

Authors: Renaud Dubois and Simon Masson.

Acknowledgements: Thomas Prest for the originial code, Zhenfei Zhang for the possible optimizations.

⚠️ This is an experimental code, not the reference code of Falcon.. It is not considered secure or suitable for production.

License: MIT.

It is possible to generate a key pair, sign a message and verify a signature in one command-line.

./sign_cli.py genkeys --version='falcon' # or 'ethfalcon'

It creates two files private_key.pem and public_key.pem storing the private and public keys. It also prints the public key in Solidity format.

./sign_cli.py sign --data=deadbeef --privkey=private_key.pem

It create a signature file sig for the given message and the private key. The signature is stored in hexadecimal format. It also prints the signature in Solidity format.

./sign_cli.py verify --data=deadbeef --pubkey=public_key.pem --signature='sig'

It outputs the validity of the signature with respect to a message and a public key given as input. The signature needs to be provided as a (large) string.

Tests of key generation, signing and verification can be done in iterative and recursive NTT. The HashToPoint can be set with the SHAKE256, KeccaXOF (implemented in Tetration), or KeccakPRNG (a PRNG based on Keccak).

make test

This runs the original tests, and additional tests made in test_xxx.py.

⚠️ This implementation is not optimized.