rust-bn254-hash/README.md

rust-bn254-hash

Rust implementation of some arithmetic hash functions over the BN254 curve's scalar field, with permutation state width t=3.

Hash functions implemented:

• Poseidon2
• Griffin
• skyscraper

We plan to integrate this into Plonky2, to allow an efficient BN254 recursive wrapper. For this we need some custom features: For example when computing the Fiat-Shamir challenges, we need a duplex construction which can absorb and squeeze both BN254 and Goldilocks field elements.

Currently using arkworks for field arithmetic (maybe replace it with something more light-weight in the future...)

Performance

Single core, unoptimized, MacBook Pro M2.

1000 permutations:

• 1000 Poseidon2 permutations: 5.24 msec (approx 12MB/sec linear hashing)
• 1000 Griffin permutations: 76.8 msec (appox 800k/sec linear hashing)
• 1000 Skyscraper permutations: 207.45 µs (width=2)

10000 permutations:

• 10000 Poseidon2 permutations: 53 msec
• 10000 Griffin permutations: 762 msec
• 10000 Skyscraper permutations: 2.2 msec (width=2)