Indexed Merkle Tree

Overview

The Indexed Merkle Tree crate provides a robust implementation of indexed Merkle trees in particular described for Transparency Dictionaries that can be used for various cryptographic applications. Compared to normal Merkle trees, this implementation provides proofs for both membership and non-membership, ensuring uniqueness of leaf nodes.

Breaking Changes in Version 0.5.0

Version 0.5.0 introduces breaking changes:

Hash Value Type Change: The crate no longer uses String for hash values. Instead, a custom Hash struct is implemented:

#[derive(Serialize, Deserialize, Debug, Clone, PartialEq, Eq)]
pub struct Hash([u8; 32]);

impl Hash {
    pub const fn new(bytes: [u8; 32]) -> Self {
        Hash(bytes)
    }

    pub fn from_hex(hex: &str) -> Result<Self, hex::FromHexError> {
        let bytes = hex::decode(hex)?;
        if bytes.len() != 32 {
            return Err(hex::FromHexError::InvalidStringLength);
        }
        let mut array = [0u8; 32];
        array.copy_from_slice(&bytes);
        Ok(Hash(array))
    }

    pub fn to_hex(&self) -> String {
        hex::encode(self.0)
    }
}

impl AsRef<[u8]> for Hash {
    fn as_ref(&self) -> &[u8] {
        &self.0
    }
}

impl std::fmt::Display for Hash {
    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
        write!(f, "{}", self.to_hex())
    }
}```

Breaking Changes in Version 0.4.0

Version 0.4.0 introduces breaking changes:

Hash Value Mapping: Hash values are now computed and then taken modulo the order of the BLS12-381 curve to ensure they are mapped into the valid value range.

Features

Efficient membership and non-membership proof generation.
Update and insertion operations with verifiable proofs.
Tree size doubling for dynamic data insertion.
High integrity and order verification in data structures.

Usage

tbd

Installation

cargo add indexed_merkle_tree

Contributing

Contributions are welcome! Please feel free to get in touch.

indexed-merkle-tree 0.5.2