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

Implements a cryptographic sponge over prime fields. Implements the sponge specification from the Community Cryptographic Specification Project see https://github.com/C2SP/C2SP/blob/792c1254124f625d459bfe34417e8f6bdd02eb28/poseidon-sponge.md (Note: this spec was not accepted into the C2SP repo, we might want to reference something else!) More...

#include <sponge.hpp>

Public Types
enum	Mode { ABSORB , SQUEEZE }
	Defines what phase of the sponge algorithm we are in. More...

Public Member Functions
	FieldSponge (FF domain_iv=0)
std::array< FF, rate >	perform_duplex ()
void	absorb (const FF &input)
FF	squeeze ()

Static Public Member Functions
template<size_t out_len, bool is_variable_length>
static std::array< FF, out_len >	hash_internal (std::span< FF > input)
	Use the sponge to hash an input string.
template<size_t out_len>
static std::array< FF, out_len >	hash_fixed_length (std::span< FF > input)
static FF	hash_fixed_length (std::span< FF > input)
template<size_t out_len>
static std::array< FF, out_len >	hash_variable_length (std::span< FF > input)
static FF	hash_variable_length (std::span< FF > input)

Public Attributes
std::array< FF, t >	state
std::array< FF, rate >	cache
size_t	cache_size = 0
Mode	mode = Mode::ABSORB

Detailed Description

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

Implements a cryptographic sponge over prime fields. Implements the sponge specification from the Community Cryptographic Specification Project see https://github.com/C2SP/C2SP/blob/792c1254124f625d459bfe34417e8f6bdd02eb28/poseidon-sponge.md (Note: this spec was not accepted into the C2SP repo, we might want to reference something else!)

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

Member Enumeration Documentation

Mode

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

enum crypto::FieldSponge::Mode

Defines what phase of the sponge algorithm we are in.

   ABSORB: 'absorbing' field elements into the sponge
   SQUEEZE: compressing the sponge and extracting a field element

Member Function Documentation

hash_internal()

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

template<size_t out_len, bool is_variable_length>

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

inlinestatic

Use the sponge to hash an input string.

Template Parameters

out_len
is_variable_length.	Distinguishes between hashes where the preimage length is constant/not constant

Parameters

input

Returns

std::array<FF, out_len>

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

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