keccak256-circom

Keccak256 hash function (ethereum version) implemented in circom. Spec: https://nvlpubs.nist.gov/nistpubs/FIPS/NIST.FIPS.202.pdf

Warning: WIP, this is an experimental repo.

Status

Initial version works, compatible with Ethereum version of Keccak256. This version is modified from arnaucube's to accept arbitrary input size (the original was limited to 1080 bits).

It needs around 150848 (151k) constraints (more for sizes that require multiple 1088-bit blocks, about 150k per block).

For context: Rapidsnark proof generation time:

• 1.1M constraints -> 7 seconds (8 CPU)
• 128M constraints -> <2min (64 CPU)

Usage

• import the lib in the package.json:

"dependencies": {
	"keccak256-circom": "git+https://github.com/jasonmorton/keccak256-circom"
}

• Usage:

pragma circom 2.0.0;

include "../node_modules/keccak256-circom/circuits/keccak.circom";

// for a input & output of 32 bytes:
component main = Keccak(32*8, 32*8);