Struct MerkleTreeHidingMmcs

pub struct MerkleTreeHidingMmcs<P, PW, H, C, R, const DIGEST_ELEMS: usize, const SALT_ELEMS: usize> { /* private fields */ }

A vector commitment scheme backed by a MerkleTree.

This is similar to MerkleTreeMmcs, but each leaf is “salted” with random elements. This is done to turn the Merkle tree into a hiding commitment. See e.g. Section 3 of Interactive Oracle Proofs.

SALT_ELEMS should be set such that the product of SALT_ELEMS with the size of the value (P::Value) is at least the target security parameter.

R should be an appropriately seeded cryptographically secure pseudorandom number generator (CSPRNG). Something like ThreadRng may work, although it relies on the operating system to provide sufficient entropy.

Generics:

• P: a leaf value
• PW: an element of a digest
• H: the leaf hasher
• C: the digest compression function
• R: a random number generator for blinding leaves

Implementations

impl<P, PW, H, C, R, const DIGEST_ELEMS: usize, const SALT_ELEMS: usize> MerkleTreeHidingMmcs<P, PW, H, C, R, DIGEST_ELEMS, SALT_ELEMS>

pub fn new(hash: H, compress: C, rng: R) -> Self

Trait Implementations

impl<P: Clone, PW: Clone, H: Clone, C: Clone, R: Clone, const DIGEST_ELEMS: usize, const SALT_ELEMS: usize> Clone for MerkleTreeHidingMmcs<P, PW, H, C, R, DIGEST_ELEMS, SALT_ELEMS>

fn clone( &self, ) -> MerkleTreeHidingMmcs<P, PW, H, C, R, DIGEST_ELEMS, SALT_ELEMS>

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl<P: Debug, PW: Debug, H: Debug, C: Debug, R: Debug, const DIGEST_ELEMS: usize, const SALT_ELEMS: usize> Debug for MerkleTreeHidingMmcs<P, PW, H, C, R, DIGEST_ELEMS, SALT_ELEMS>

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl<P, PW, H, C, R, const DIGEST_ELEMS: usize, const SALT_ELEMS: usize> Mmcs<<P as PackedValue>::Value> for MerkleTreeHidingMmcs<P, PW, H, C, R, DIGEST_ELEMS, SALT_ELEMS>

where P: PackedValue, P::Value: Serialize + DeserializeOwned, PW: PackedValue, H: CryptographicHasher<P::Value, [PW::Value; DIGEST_ELEMS]> + CryptographicHasher<P, [PW; DIGEST_ELEMS]> + Sync, C: PseudoCompressionFunction<[PW::Value; DIGEST_ELEMS], 2> + PseudoCompressionFunction<[PW; DIGEST_ELEMS], 2> + Sync, R: Rng + Clone, PW::Value: Eq, [PW::Value; DIGEST_ELEMS]: Serialize + for<'de> Deserialize<'de>, Standard: Distribution<P::Value>,

type Proof = (Vec<Vec<<P as PackedValue>::Value>>, Vec<[<PW as PackedValue>::Value; DIGEST_ELEMS]>)

The first item is salts; the second is the usual Merkle proof (sibling digests).

type ProverData<M> = MerkleTree<<P as PackedValue>::Value, <PW as PackedValue>::Value, HorizontalPair<M, DenseMatrix<<P as PackedValue>::Value>>, DIGEST_ELEMS>

type Commitment = Hash<<P as PackedValue>::Value, <PW as PackedValue>::Value, DIGEST_ELEMS>

type Error = MerkleTreeError

fn commit<M: Matrix<P::Value>>( &self, inputs: Vec<M>, ) -> (Self::Commitment, Self::ProverData<M>)

fn open_batch<M: Matrix<P::Value>>( &self, index: usize, prover_data: &Self::ProverData<M>, ) -> (Vec<Vec<P::Value>>, (Vec<Vec<P::Value>>, Vec<[PW::Value; DIGEST_ELEMS]>))

Opens a batch of rows from committed matrices returns (openings, proof) where openings is a vector whose ith element is the jth row of the ith matrix M[i], and j = index >> (log2_ceil(max_height) - log2_ceil(M[i].height)).

fn get_matrices<'a, M: Matrix<P::Value>>( &self, prover_data: &'a Self::ProverData<M>, ) -> Vec<&'a M>

Get the matrices that were committed to.

fn verify_batch( &self, commit: &Self::Commitment, dimensions: &[Dimensions], index: usize, opened_values: &[Vec<P::Value>], proof: &Self::Proof, ) -> Result<(), Self::Error>

Verify a batch opening. index is the row index we’re opening for each matrix, following the same semantics as open_batch. dimensions is a slice whose ith element is the dimensions of the matrix being opened in the ith opening

fn commit_matrix<M>(&self, input: M) -> (Self::Commitment, Self::ProverData<M>)

where M: Matrix<T>,

fn commit_vec( &self, input: Vec<T>, ) -> (Self::Commitment, Self::ProverData<DenseMatrix<T>>)

where T: Clone + Send + Sync,

fn get_matrix_heights<M>(&self, prover_data: &Self::ProverData<M>) -> Vec<usize>

where M: Matrix<T>,

fn get_max_height<M>(&self, prover_data: &Self::ProverData<M>) -> usize

where M: Matrix<T>,

Get the largest height of any committed matrix.