pyjubjub 0.1.0

Python interface to the Jubjub elliptic curve used in Zcash Protocol

pyjubjub

Python bindings to rust code that implements the Jubjub elliptic curve and RedDSA, a Schnorr-based signature scheme that supports key re-randomization, which is defined in the Zcash Protocol. RedDSA on the Jubjub curve is known as RedJubjub.

RedJubjub on the Jubjub elliptic curve plays the same role as ed25519 on the elliptic curve Curve25519.

Details

There are various Rust implementations of Jubjub, we use what is inside the version of librustzcash used by the Hush full node, which is an older version of librustzcash used in the zcashd Zcash full node. The current version of zcashd librustzcash has many changes to support Halo2/Orchard that we do not need for Jubjub. We do not use the jubjub crate from Zebra, the Zcash full node written in Rust.

The file src/lib.rs in this repo is https://git.hush.is/hush/librustzcash/src/branch/master/sapling-crypto/src/redjubjub.rs with python bindings provided by pyo3 from https://github.com/PyO3/pyo3

In theory this code is compatible with the Sapling zaddrs which use the Jubjub elliptic curve in the following cryptocoins: Hush, DragonX, Zcash, Ycash, Pirate and probably others. Testing is needed to verify this.

Compiling

Currently this code has only been tested with rust 1.63.0 .

Setup python environment:

    virtualenv venv
    source venv/bin/activate

Install maturin via pip install maturin

After changing code, compile Rust and Python module:

    maturin develop -r

The -r builds a release optimized version. You can leave it off if you want, but the current tests are ~50X slower without it.

Example Use

This code is still HIGHLY EXPERIMENTAL and UNTESTED. Don't say we didn't warn you.

import pyjubjub
privkey = pyjubjub.new_privkey()
pubkey = pyjubjub.get_pubkey(privkey)

Tests

To run tests:

python test.py

Installing

This is not yet available on PyPI

Requirements

pyjubjub requires Python 3.8 or higher

License

GPLv3