# BLS12::381 for Ruby [![Build Status](https://github.com/azuchi/bls12-381/actions/workflows/main.yml/badge.svg?branch=main)](https://github.com/azuchi/bls12-381/actions/workflows/main.yml/badge.svg?branch=main) [![Gem Version](https://badge.fury.io/rb/bls12-381.svg)](https://badge.fury.io/rb/bls12-381) [![MIT License](http://img.shields.io/badge/license-MIT-blue.svg?style=flat)](LICENSE)

This library is a Ruby BLS12-381 implementation based on the JavaScript implementation [noble-bls12-381](https://github.com/paulmillr/noble-bls12-381).

Note: This library has passed the same tests as noble-bls12-381, but has not been audited to prove its safety.
Please be careful when using this.

## Installation

Add this line to your application's Gemfile:

```ruby
gem 'bls12-381'
```

And then execute:

    $ bundle install

Or install it yourself as:

    $ gem install bls12-381

## Usage

```ruby
require 'bls'

# Generate private key.
private_key = SecureRandom.random_number(BLS::Curve::P)

# Or you can use hex string.
private_key = '67d53f170b908cabb9eb326c3c337762d59289a8fec79f7bc9254b584b73265c'

# Generate public key from private key.
public_key = BLS.get_public_key(private_key)
# Public key is BLS::PointG1 object.

# sign and verify
message = '64726e3da8'

signature = BLS.sign(message, private_key)
# signature is BLS::PointG2 object. You can get signature with hex format using #to_signature method.
signature.to_signature

is_correct = BLS.verify(signature, message, public_key)
=> true

# Sign 1 msg with 3 keys
private_keys = [
  '18f020b98eb798752a50ed0563b079c125b0db5dd0b1060d1c1b47d4a193e1e4',
  'ed69a8c50cf8c9836be3b67c7eeff416612d45ba39a5c099d48fa668bf558c9c',
  '16ae669f3be7a2121e17d0c68c05a8f3d6bef21ec0f2315f1d7aec12484e4cf5'
]
public_keys = private_keys.map { |p| BLS.get_public_key(p) }

signatures2 = private_keys.map { |p| BLS.sign(message, p) }
agg_public_keys2 = BLS.aggregate_public_keys(public_keys)
agg_signatures2 = BLS.aggregate_signatures(signatures2)
is_correct2 = BLS.verify(agg_signatures2, message, agg_public_keys2)
=> true

# Sign 3 msgs with 3 keys
messages = %w[d2 0d98 05caf3]
signatures3 = private_keys.map.with_index { |p, i| BLS.sign(messages[i], p)}
agg_signatures3 = BLS.aggregate_signatures(signatures3)
is_correct3 = BLS.verify_batch(agg_signatures3, messages, public_keys)
=> true
```

## License

The gem is available as open source under the terms of the [MIT License](https://opensource.org/licenses/MIT).

## Code of Conduct

Everyone interacting in the Bls12::381 project's codebases, issue trackers, chat rooms and mailing lists is expected to follow the [code of conduct](https://github.com/[USERNAME]/bls12-381/blob/master/CODE_OF_CONDUCT.md).