Struct r1cs::Sponge

pub struct Sponge<F: Field, MP: MultiPermutation<F>> { /* fields omitted */ }

A sponge function.

In a SNARK setting, efficiency demands that the two sections of sponge state memory (R and C) be stored in separate field elements, so that inputs can be efficiently added to R without affecting C.

Methods

impl<F: Field, MP: MultiPermutation<F>> Sponge<F, MP>

pub fn new(permutation: MP, bitrate: usize, capacity: usize) -> Self

Create a new sponge function.

Parameters

• permutation - the permutation with which to transform state memory
• bitrate - the size of the input section, in field elements
• capacity - the size of the capacity section, in field elements

pub fn evaluate(
    &self,
    builder: &mut GadgetBuilder<F>,
    inputs: &[Expression<F>],
    output_len: usize
) -> Vec<Expression<F>>