bb::crypto::FieldSponge< FF, rate, capacity, t, Permutation > Class Template Reference

Implements a cryptographic sponge over prime fields. Sponge construction follows the Duplex Sponge model (https://keccak.team/files/SpongeDuplex.pdf). Domain separation uses IV = (input_length << 64) per Section 4.2 of the Poseidon paper (https://eprint.iacr.org/2019/458.pdf). Permutation is Poseidon2 (https://eprint.iacr.org/2023/323.pdf). More...

#include <sponge.hpp>

Static Public Member Functions
static FF	hash_internal (std::span< const FF > input)
	Use the sponge to hash an input vector.
static FF	hash_internal (std::span< const FF > input, FF iv)
	Use the sponge to hash an input vector with a custom IV.

Private Member Functions
	FieldSponge (FF domain_iv)
void	perform_duplex ()
void	absorb (const FF &input)
FF	squeeze ()

Private Attributes
std::array< FF, t >	state {}
std::array< FF, rate >	cache {}
size_t	cache_size = 0

Detailed Description

template<typename FF, size_t rate, size_t capacity, size_t t, typename Permutation>
class bb::crypto::FieldSponge< FF, rate, capacity, t, Permutation >

Implements a cryptographic sponge over prime fields. Sponge construction follows the Duplex Sponge model (https://keccak.team/files/SpongeDuplex.pdf). Domain separation uses IV = (input_length << 64) per Section 4.2 of the Poseidon paper (https://eprint.iacr.org/2019/458.pdf). Permutation is Poseidon2 (https://eprint.iacr.org/2023/323.pdf).

Note: If we ever use this sponge class for more than 1 hash functions, we should move this out of poseidon2 and into its own directory

Template Parameters

FF
rate
capacity
t
Permutation

Definition at line 33 of file sponge.hpp.

Constructor & Destructor Documentation

FieldSponge()

template<typename FF , size_t rate, size_t capacity, size_t t, typename Permutation >

bb::crypto::FieldSponge< FF, rate, capacity, t, Permutation >::FieldSponge ( FF  domain_iv )

inlineprivate

Definition at line 42 of file sponge.hpp.

Member Function Documentation

absorb()

template<typename FF , size_t rate, size_t capacity, size_t t, typename Permutation >

void bb::crypto::FieldSponge< FF, rate, capacity, t, Permutation >::absorb ( const FF &  input )

inlineprivate

Definition at line 58 of file sponge.hpp.

hash_internal() [1/2]

template<typename FF , size_t rate, size_t capacity, size_t t, typename Permutation >

static FF bb::crypto::FieldSponge< FF, rate, capacity, t, Permutation >::hash_internal ( std::span< const FF >  input )

inlinestatic

Use the sponge to hash an input vector.

Parameters

input

Field elements (a_0, ..., a_{N-1})

Returns

Hash of the input, a single field element.

Definition at line 85 of file sponge.hpp.

hash_internal() [2/2]

template<typename FF , size_t rate, size_t capacity, size_t t, typename Permutation >

static FF bb::crypto::FieldSponge< FF, rate, capacity, t, Permutation >::hash_internal ( std::span< const FF >  input, FF  iv  )

inlinestatic

Use the sponge to hash an input vector with a custom IV.

Parameters

input	Field elements (a_0, ..., a_{N-1})
iv	Initial value for domain separation

Returns

Hash of the input, a single field element.

Definition at line 99 of file sponge.hpp.

perform_duplex()

template<typename FF , size_t rate, size_t capacity, size_t t, typename Permutation >

void bb::crypto::FieldSponge< FF, rate, capacity, t, Permutation >::perform_duplex ( )

inlineprivate

Definition at line 44 of file sponge.hpp.

squeeze()

template<typename FF , size_t rate, size_t capacity, size_t t, typename Permutation >

FF bb::crypto::FieldSponge< FF, rate, capacity, t, Permutation >::squeeze ( )

inlineprivate

Definition at line 72 of file sponge.hpp.

Member Data Documentation

cache

template<typename FF , size_t rate, size_t capacity, size_t t, typename Permutation >

std::array<FF, rate> bb::crypto::FieldSponge< FF, rate, capacity, t, Permutation >::cache {}

private

Definition at line 39 of file sponge.hpp.

cache_size

template<typename FF , size_t rate, size_t capacity, size_t t, typename Permutation >

size_t bb::crypto::FieldSponge< FF, rate, capacity, t, Permutation >::cache_size = 0

private

Definition at line 40 of file sponge.hpp.

state

template<typename FF , size_t rate, size_t capacity, size_t t, typename Permutation >

std::array<FF, t> bb::crypto::FieldSponge< FF, rate, capacity, t, Permutation >::state {}

private

Definition at line 36 of file sponge.hpp.

---

The documentation for this class was generated from the following file:

• src/barretenberg/crypto/poseidon2/sponge/sponge.hpp