MerkleTree

A straight forward implementation of a binary balanced Merkle trees and proofs in JavaScript. Compatible with any hash function. Specially designed for the use of Poseidon in Circom.

Install

npm install @applied-crypto/merkletree

Usage

// Use your own hash function
poseidon = await buildPoseidonOpt();
leafHash = function(input) {
    return poseidon([input]);
}
nodeHash = function(left, right) {
    return poseidon([left, right]);
}

let inputs = new Array(2**10).fill(0);
// Create the Merkle tree
tree = merkleTree(inputs, leafHash, nodeHash);
// Create the Merkle proof
let merkleProof = tree.getMerkleProof(293);

// Validate merkle Proof
let root = merkleProof.calculateRoot();
assert(poseidon.F.toObject(tree.root) === poseidon.F.toObject(root), true);

Validating Merkle proofs in Zero-Knowledge Proofs (ZKPs)

For validating the generated Merkle proofs in Circom, see the circuit.circom.

Disclaimer

Only for research purpose. No security audits done. Don't use in production.

@Branch Business and Information System Engineering of the Fraunhofer FIT