# blst-ts

![ETH2.0_Spec_Version 0.12.0](https://img.shields.io/badge/ETH2.0_Spec_Version-0.12.0-2e86c1.svg)
![ES Version](https://img.shields.io/badge/ES-2017-yellow)
![Node Version](https://img.shields.io/badge/node-16.x-green)

Typescript wrapper for [supranational/blst](https://github.com/supranational/blst) native bindings, a highly performant BLS12-381 signature library.

## Supported Environments

| OS / Arch     | binary name | Node                               |
| ------------- | ----------- | ---------------------------------- |
| Linux / x64   | linux-x64   | 16, 18, 20, 21 |
| Linux / arm64 | linux-arm64 | 16, 18, 20, 21 |
| Windows / x64 | win32-x64   | 16, 18, 20, 21 |
| macOS / x64     | darwin-x64  | 16, 18, 20, 21 |
| macOS / arm64      | darwin-arm64  | 16, 18, 20, 21 |

## Usage

```bash
yarn add @chainsafe/blst
```

This library comes with pre-compiled bindings for most platforms. You can check current support in [releases](https://github.com/ChainSafe/blst-ts/releases). If your platform is not supported, bindings will be compiled from source as a best effort with node-gyp.

```ts
import crypto from "crypto";
import {SecretKey, verify, BLST_CONSTANTS} from "@chainsafe/blst";

const msg = Buffer.from("sample-msg");
const sk = SecretKey.fromKeygen(crypto.randomBytes(BLST_CONSTANTS.SECRET_KEY_LENGTH));
const pk = sk.toPublicKey();
const sig = sk.sign(msg);

console.log(verify(msg, pk, sig)); // true
```

## Spec versioning

This library has a hardcoded configuration compatible with Eth2.0 spec:

| Setting        | value                                         |
| -------------- | --------------------------------------------- |
| PK_IN          | `G1`                                          |
| HASH_OR_ENCODE | `true`                                        |
| DST            | `BLS_SIG_BLS12381G2_XMD:SHA-256_SSWU_RO_POP_` |
| RAND_BITS      | `64`                                          |

> [spec](https://github.com/ethereum/eth2.0-specs/blob/v0.11.1/specs/phase0/beacon-chain.md#bls-signatures)

> [test vectors](https://github.com/ethereum/consensus-spec-tests/tree/master/tests/general)

## Contributing

Please check out [CONTRIBUTING.md](./CONTRIBUTING.md) for more info on how to use the repo and for architectural details

## Release/Publishing

The release process is automatically [triggered](.github/workflows/main.yml#L198) when a change to the version in package.json is merged to master.  See [CONTRIBUTING.md](./CONTRIBUTING.md) for more specifics about how the release and package are built.

## License

Apache-2.0
