OTP

Collection of one-time password algorithms

Features

• Generate HOTP, TOTP, SteamTOTP
• Validate TOTP with the time offset
• Create TOTP Iterator
• Create otpauth uri

Usage

Generate TOTP

import {otpauth, readableTotp, totp, totpValidate} from '@maks11060/otp'

const secret = crypto.getRandomValues(new Uint8Array(20))

// Get code
const code = await totp({secret}) // 380577

// Codes iterator
for await (const {code, timeLeft} of readableTotp(totp, {secret})) {
  console.log({code, timeLeft}) // { code: "380577", timeLeft: 15 }
}

// Create otpauth uri
otpauth({secret, issuer: 'App name', label: '@username'}).toString()
// otpauth://totp/lable?secret=00&algorithm=SHA1&issuer=App+name

// Validate totp with time window
await totpValidate({secret, code}) // true

Generate HOTP

import {hotp, readableTotp} from '@maks11060/otp'

const secret = crypto.getRandomValues(new Uint8Array(20))
const code = await hotp({secret, counter: 1})

Generate SteamTOTP

import {readableTotp, steamTotp} from '@maks11060/otp'
import {decodeBase64} from '@std/encoding/base64'

const secret = decodeBase64('STEAM_SHARED_SECRET') // Decode key to ArrayBuffer

// Get code
const code = await steamTotp({secret})
console.log(code) // "KQXVF"

// Codes iterator
for await (const {code, timeLeft} of readableTotp(steamTotp, {secret})) {
  console.log({code, timeLeft}) // { code: "KQXVF", timeLeft: 25 }
}

Supported apps

Apps	Algs	Period	Digits
Google Authenticator	SHA1	30	6
Microsoft Authenticator	SHA1	30	6