Function keccak256 

pub fn keccak256(
    builder: &CircuitBuilder,
    message: &[Wire],
    len_bytes: usize,
) -> [Wire; 4]

Computes the Keccak-256 hash of a fixed-length message.

This function creates a circuit that computes the Keccak-256 digest of a message with a known, fixed length at circuit construction time. It’s more efficient than the variable-length version as it doesn’t need runtime length checks or multiplexing.

Arguments

• builder - Circuit builder for constructing constraints
• message - Input message as packed 64-bit words (8 bytes per wire)
• len_bytes - The exact length of the message in bytes

Returns

• [Wire; 4] - The Keccak-256 digest as 4 wires of 64 bits each

Panics

• If message.len() does not equal exactly len_bytes.div_ceil(8)

Example

use binius_circuits::keccak::fixed_length::keccak256;
use binius_frontend::CircuitBuilder;

let builder = CircuitBuilder::new();

// Create input wires for a 32-byte message
let message: Vec<_> = (0..4).map(|_| builder.add_witness()).collect();

// Compute Keccak-256 of the 32-byte message
let digest = keccak256(&builder, &message, 32);