alloy-merkle-tree

Minimal Merkle Tree implementation

• various tree implementation
  • PerfectBinaryMerkleTree
  • IncrementalMerkleTree
  • StandardBinaryTree
• type compatible with alloy-primitives
• keccak hash as native hash
• support features: insert, proof, verify

Install

❯ cargo add alloy-merkle-tree

Support

MerkleTree

Perfect Binary Merkle Tree

let mut tree = MerkleTree::new();
// Should be 2 ^ N leaves
let num_leaves = 16;
for i in 0..num_leaves {
    tree.insert(B256::from(U256::from(i)));
}
tree.finish();

for i in 0..num_leaves {
    let proof = tree.create_proof(&B256::from(U256::from(i))).unwrap();
    assert!(MerkleTree::verify_proof(&proof));
}

IncrementalMerkleTree

used in the ETH2 Deposit Contract

 let mut tree = IncrementalMerkleTree::<8>::new();
for i in 0..1 << (8 - 1) {
    tree.append([i as u8; 32].into()).unwrap();
}
for i in 0..1 << (8 - 1) {
    let leaf = [i as u8; 32].into();
    let proof = tree.proof_at_index(i).unwrap();
    assert!(tree.verify_proof(leaf, i, &proof));
}

StandardBinaryMerkleTree

StandardMerkleTree

let num_leaves = 1000;
let mut leaves = Vec::new();
for i in 0..num_leaves {
    leaves.push(i.to_string());
}
let tree = StandardMerkleTree::of_sorted(leaves.clone());

for leaf in leaves.iter() {
    let proof = tree.get_proof(leaf);
    let bool = tree.verify_proof(leaf.to_string(), proof);
    assert!(bool);
}

reference

• merkle-tree
• StandardMerkleTree