# libp2p-crypto-secp256k1 > Support for secp256k1 keys in libp2p-crypto Latest version **0.4.3** (published 2020-03-25) · MIT license · 0 weekly downloads > **Deprecated.** This package is deprecated. ## Install ```sh npm install libp2p-crypto-secp256k1 pnpm add libp2p-crypto-secp256k1 yarn add libp2p-crypto-secp256k1 bun add libp2p-crypto-secp256k1 ``` ## Health **Score 10/100 (F)** — status: deprecated. Negative: deprecated. ## Facts | | | |---|---| | Version | 0.4.3 | | Published | 2020-03-25 | | First published | 2017-02-09 | | Weekly downloads | 0 | | License | MIT | | TypeScript types | none | | Module format | CommonJS | | Node | >=6.0.0 | | Dependencies | 5 | | Unpacked size | 3.1 MB | | Known vulnerabilities | 0 | | Install scripts | no | | GitHub stars | 10 | | Maintainers | daviddias, dignifiedquire | | Keywords | IPFS, libp2p, crypto, secp256k1 | ## Links - npm: https://www.npmjs.com/package/libp2p-crypto-secp256k1 - Repository: https://github.com/libp2p/js-libp2p-crypto-secp256k1 - Issues: https://github.com/libp2p/js-libp2p-crypto-secp256k1/issues - npm.io page: https://npm.io/package/libp2p-crypto-secp256k1 ## Dependencies (5) - [buffer](https://npm.io/package/buffer.md) ^5.5.0 - [multibase](https://npm.io/package/multibase.md) ^0.7.0 - [secp256k1](https://npm.io/package/secp256k1.md) ^4.0.0 - [is-typedarray](https://npm.io/package/is-typedarray.md) ^1.0.0 - [multihashing-async](https://npm.io/package/multihashing-async.md) ^0.8.1 ## Alternatives - [@gemini-wallet/core](https://npm.io/package/@gemini-wallet/core.md) — 515.6K weekly downloads - [utility](https://npm.io/package/utility.md) — 416.6K weekly downloads - [@primno/dpapi](https://npm.io/package/@primno/dpapi.md) — 7.2K weekly downloads - [pi-readseek](https://npm.io/package/pi-readseek.md) — 3.7K weekly downloads - [@emilia-protocol/verify](https://npm.io/package/@emilia-protocol/verify.md) — 1.1K weekly downloads ## Recent versions - 0.4.3 (latest) — 2020-03-25 - 0.4.2 — 2020-03-17 - 0.4.1 — 2020-01-06 - 0.4.0 — 2019-07-10 - 0.3.1 — 2019-07-10 - 0.3.0 — 2019-02-20 - 0.2.3 — 2019-01-08 - 0.2.2 — 2017-07-22 - 0.2.1 — 2017-07-22 - 0.2.0 — 2017-07-22 - 0.1.4 — 2017-02-12 - 0.1.3 — 2017-02-11 - 0.1.2 — 2017-02-09 - 0.1.0 — 2017-02-09 ## README # js-libp2p-crypto-secp256k1 [![](https://img.shields.io/badge/made%20by-Protocol%20Labs-blue.svg?style=flat-square)](http://protocol.ai) [![](https://img.shields.io/badge/project-libp2p-yellow.svg?style=flat-square)](http://libp2p.io/) [![](https://img.shields.io/badge/freenode-%23libp2p-yellow.svg?style=flat-square)](http://webchat.freenode.net/?channels=%23libp2p) [![Discourse posts](https://img.shields.io/discourse/https/discuss.libp2p.io/posts.svg)](https://discuss.libp2p.io) [![](https://img.shields.io/codecov/c/github/libp2p/js-libp2p-crypto-secp256k1.svg?style=flat-square)](https://codecov.io/gh/libp2p/js-libp2p-crypto-secp256k1) [![](https://img.shields.io/travis/libp2p/js-libp2p-crypto-secp256k1.svg?style=flat-square)](https://travis-ci.com/libp2p/js-libp2p-crypto-secp256k1) [![Dependency Status](https://david-dm.org/libp2p/js-libp2p-crypto-secp256k1.svg?style=flat-square)](https://david-dm.org/libp2p/js-libp2p-crypto-secp256k1) [![js-standard-style](https://img.shields.io/badge/code%20style-standard-brightgreen.svg?style=flat-square)](https://github.com/feross/standard) ![](https://img.shields.io/badge/npm-%3E%3D3.0.0-orange.svg?style=flat-square) ![](https://img.shields.io/badge/Node.js-%3E%3D4.0.0-orange.svg?style=flat-square) > Support for secp256k1 keys in js-libp2p-crypto This repo contains a [js-libp2p-crypto](https://github.com/libp2p/js-libp2p-crypto)-compatible implementation of cryptographic signature generation and verification using the [secp256k1 elliptic curve](https://en.bitcoin.it/wiki/Secp256k1) popularized by Bitcoin and other crypto currencies. ## Lead Captain [Friedel Ziegelmayer](https://github.com/dignifiedquire/) ## Table of Contents - [Install](#install) - [Usage](#usage) - [Example](#example) - [API](#api) - [`generateKeyPair([bits])`](#generatekeypairbits) - [`unmarshalSecp256k1PublicKey(bytes)`](#unmarshalsecp256k1publickeybytes) - [`unmarshalSecp256k1PrivateKey(bytes)`](#unmarshalsecp256k1privatekeybytes) - [`Secp256k1PublicKey`](#secp256k1publickey) - [`.verify(data, sig)`](#verifydata-sig) - [`Secp256k1PrivateKey`](#secp256k1privatekey) - [`.public`](#public) - [`.sign(data)`](#signdata) - [Contribute](#contribute) - [License](#license) ## Install ```sh npm install --save libp2p-crypto-secp256k1 ``` ## Usage This module is designed to work with [js-libp2p-crypto](https://github.com/libp2p/js-libp2p-crypto). Installing `libp2p-crypto-secp256k1` will automatically add support for the `'secp256k1'` key type, which can be used as an argument to the [libp2p-crypto API functions](https://github.com/libp2p/js-libp2p-crypto#api) `generateKeyPair`, `unmarshalPublicKey`, and `marshalPrivateKey`. The keys returned from those functions will be instances of the `Secp256k1PublicKey` or `Secp256k1PrivateKey` classes provided by this module. ### Example ```js const crypto = require('libp2p-crypto') const msg = Buffer.from('Hello World') const key = await crypto.generateKeyPair('secp256k1', 256) // assuming no error, key will be an instance of Secp256k1PrivateKey // the public key is available as key.public const sig = await key.sign(msg) const valid = await key.public.verify(msg, sig) assert(valid, 'Something went horribly wrong') ``` ## API The functions below are the public API of this module. For usage within `libp2p-crypto`, see the [`libp2p-crypto` API documentation](https://github.com/libp2p/js-libp2p-crypto#api). ### `generateKeyPair([bits])` - `bits: Number` - Optional, included for compatibility with js-libp2p-crypto. Ignored if present; private keys will always be 256 bits. Returns `Promise` ### `unmarshalSecp256k1PublicKey(bytes)` - `bytes: Buffer` Converts a serialized secp256k1 public key into an instance of `Secp256k1PublicKey` and returns it ### `unmarshalSecp256k1PrivateKey(bytes)` - `bytes: Buffer` Returns `Promise` Converts a serialized secp256k1 private key into an instance of `Secp256k1PrivateKey`. ### `Secp256k1PublicKey` #### `.verify(data, sig)` - `data: Buffer` - `sig: Buffer` Returns `Promise` Calculates the SHA-256 hash of `data`, and verifies the DER-encoded signature in `sig`. ### `Secp256k1PrivateKey` #### `.public` Accessor for the `Secp256k1PublicKey` associated with this private key. #### `.sign(data)` - `data: Buffer` Returns `Promise` Calculates the SHA-256 hash of `data` and signs it, resolves with the DER-encoded signature. ## Contribute Feel free to join in. All welcome. Open an [issue](https://github.com/libp2p/js-libp2p-crypto-secp256k1/issues)! This repository falls under the IPFS [Code of Conduct](https://github.com/ipfs/community/blob/master/code-of-conduct.md). [![](https://cdn.rawgit.com/jbenet/contribute-ipfs-gif/master/img/contribute.gif)](https://github.com/ipfs/community/blob/master/contributing.md) ## License [MIT](LICENSE) --- _Source: https://npm.io/package/libp2p-crypto-secp256k1 · Machine-readable twin of the npm.io package page. Health data is recomputed on every publish._