oliverne / easy-ecdsa

Easy & Simple ECDSA Signer/Verifier for who has a headache 🙀

@oliverne/easy-ecdsa

Easy & Simple ECDSA(Elliptic Curve Digital Signature Algorithm) Signer/Verifier for who has a headache.

It can works on React Native apps. without installing any native dependencies.

Features

• Super easy but not configurable
• Shipped with TypeScript declaration
• Pure JS implementation due to other great libraries
• It works on NodeJS, browsers and even React Native

  But for performance reasons, you have some better alternatives for NodeJS.

Security

• It DOESN'T rely on NodeJS crypto.randombytes() and window.crypto.getRandomValues() So it is NOT considered cryptographically secured.

• Instead of native crypto API, it depends on seedrandom to creates random values based on ARC4-based PRNG.

• A message for signing is hashed by using SHA256. Although the output is Base58 encoded string, it is not "Double Hashing" and neither compatible with the formats used by crypto currency.

Install

npm install @oliverne/easy-ecdsa

OR

yarn add @oliverne/easy-ecdsa

Usage

import { ECDSA } from '@oliverne/easy-ecdsa';

const signer = new ECDSA();

const sig = signer.sign('My precious message'); // string
// OR
const sig = signer.sign(['foo', 'bar', 1234, 5678]); // an array of string or unsigned integer

console.log('Public key:', signer.publicKey); 
// output: Base58 encoded public key string

console.log('Signature:', sig); 
// output: Base58 encoded signature string derived from the message digest hashed by SHA256

console.log('Verified with own public key:', signer.verify(message, sig)); 
// output: true

console.log(
  'Verified with a foreign public key:',
  signer.verify(myMessage, sig, 'WrQng9999PubKey')
);
// output: false

Compatibility

Tested on:

• NodeJS >= 12
• Latest browsers that fully support ES2015, Not IE
• React Native >=0.62

Fun Facts

• 📈 I don't understand Elliptic curve.
• 🔐 I don't know anything about crypto.
• 🤣 It was built for providing a client-side message signature working on React Native without native dependencies.