This is a Node.js/WASM port of the SPAKE2 algorithm. SPAKE2 is a secure method for deriving a shared secret from a low entropy password.
For the default security level each message is 33 bytes long. The resulting secrets are Ed25519 elliptic curve keys, roughly equivalent to an 128-bit symmetric key.
Read the Rust library documentation for more information on how this works, it's pretty good!
It also works in the browser! See how to use this in the browser in the example directory.
npm i spake2-wasm
import * as spake2 from "spake2-wasm";
let appid = 'myapp/v1';
let password = 'pineapple sausage';
// peer A sends start message
let Astate = spake2.start(appid, password);
let Amsg = spake2.msg(Astate)
// peer B sends start message
let Bstate = spake2.start(appid, password);
let Bmsg = spake2.msg(Bstate)
// Both sides receive the start message and generate a key
let Akey = spake2.finish(Astate, Bmsg);
let Bkey = spake2.finish(Bstate, Amsg);
// These resulting secret keys should be the same
console.log(Akey.toString('hex') === Bkey.toString('hex'))Thanks to this Node.js port of Magic Wormhole for the details necessary to get spake2 running in wasm.
MIT