merkle-lite

A simple, fast, and composable binary Merkle tree and proof for Rust Crypto hash functions.

Examples

It's super simple to compose MerkleTree from the ordered array of hashes and verify the proof of inclusion with MerkleProof:

use merkle_lite::MerkleTree;
use rand_core::RngCore;

// Composes MerkleTree from the 50,000 random hashes.
let tree: MerkleTree<sha3::Sha3_256> = std::iter::repeat([0u8; 32])
    .map(|mut leaf| {
        rand_core::OsRng.fill_bytes(&mut leaf);
        leaf
    })
    .take(50_000)
    .collect();

// Verifies the proof of inclusion for the arbitrary leaves.
let tree_leaves = tree.get_leaves();
let leaf_indices = [12, 0, 1, 1201, 13_903, 980];
let leaf_hashes: Vec<_> = leaf_indices
    .iter()
    .map(|index| (*index, tree_leaves[*index]))
    .collect();
assert_eq!(
    tree.proof(&leaf_indices)
        .expect("proof")
        .verify(&leaf_hashes)
        .expect("verify")
        .as_ref(),
    tree.root().expect("root"),
);

License

Licensed under either of

• Apache License, Version 2.0 (LICENSE-APACHE or http://www.apache.org/licenses/LICENSE-2.0)
• MIT license (LICENSE-MIT or http://opensource.org/licenses/MIT)

at your option.

Contribution

Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in the work by you, as defined in the Apache-2.0 license, shall be dual licensed as above, without any additional terms or conditions.