Trait mrklt::Merge

pub trait Merge {
    type Hash;
    fn leaf(leaf: &Self::Hash) -> Self::Hash;
    fn merge(left: &Self::Hash, right: &Self::Hash) -> Self::Hash;
}

This trait can be implemented to allow, or to disallow second preimage attacks.

use mrklt::Merge;

impl Merge for BlockSecondPreimage {
    type Hash = [u8; 32];

    fn leaf(leaf: &Self::Hash) -> Self::Hash {
        hash(leaf)
    }

    fn merge(left: &Self::Hash, right: &Self::Hash) -> Self::Hash {
        cat_hash(left, right)
    }
}

impl Merge for AllowSecondPreimage {
    ...
    fn leaf(leaf: &Self::Hash) -> Self::Hash {
        leaf.clone()
    }
    ...
}

// Prepending 0x00 or 0x01 as described in [rfc6962](https://www.rfc-editor.org/info/rfc6962).
impl Merge for AlternativeBlockSecondPreimage {
    type Hash = Box<[u8]>;

    fn leaf(leaf: &Self::Hash) -> Self::Hash {
        let mut ret = Vec::<u8>::with_capacity(1 + leaf.len());
        ret.push(0x00);
        ret.extend_from_slice(leaf);
        ret.into_boxed_slice()
    }

    fn merge(left: &Self::Hash, right: &Self::Hash) -> Self::Hash {
        let mut ret = Vec::<u8>::from(cat_hash(left, right));
        ret.insert(0, 0x01);
        ret.into_boxed_slice()
    }
}

Associated Types

type Hash

Loading content...

Required methods

fn leaf(leaf: &Self::Hash) -> Self::Hash

Compute the hash of a leaf node.

Note: The leaf passed has already been hashed once. An implementations may modify the leaf somehow. Before inclusion.

fn merge(left: &Self::Hash, right: &Self::Hash) -> Self::Hash

Compute the hash of an inner node.

Loading content...

Implementors

Loading content...