chacha-stream

chacha-stream

This module provides encryption and decryption streams for the sodium chacha20 implementation. It can be used to encrypt channels using a key already known to both sides.

It manages communicating the stream nonce to the remote side, which is transmitted in plaintext. This is safe information to leak (the nonce is used to detect replay attacks).

Usage

const chacha = require('chacha-stream')
const through = require('through2')
const crypto = require('crypto')

function printer (prefix) {
  return through(function (chunk, enc, next) {
    console.log(prefix, chunk.toString())
    next(null, chunk)
  })
}

let key = crypto.randomBytes(32)
let encode0 = chacha.encoder(key)
let decode0 = chacha.decoder(key)

encode0.write('hello world')

encode0.pipe(printer('encrypted')).pipe(decode0).pipe(printer('decrypted'))

outputs

encrypted }�?�lx
encrypted z>��Un��4�
decrypted hello world

API

var chacha = require('chacha-stream')

var encoder = chacha.encode(key)

Creates a Transform stream that accepts plaintexts written to it, and outputs encrypted ciphertext.

key is a 32-byte Buffer.

var decoder = chacha.decode(key)

Creates a Transform stream that accepts ciphertext written to it, and outputs decrypted plaintext.

key is a 32-byte Buffer.

Install

With npm installed, run

$ npm install chacha-stream

License

ISC