HOTP TOTP


HMAC-Based One-Time Password (HOTP), and Time-Based One-Time Password (TOTP) Algorithms

Install via npm

``sh
$ npm install --save hotp
`

Changelog

- v3.0.0: Removed CLI utilities – now to be found at jhermsmeier / hotp-totp-cli
- v2.0.0: Added TOTP implementation
- v1.0.0: Initial release

Usage

$3

#### hotp( key, counter[, options] )

- key {Buffer|String}
- counter {Buffer|String|Number}
- options {Object}
- algorithm {Number} Default: 'sha1'
- digits {Number} Default: 6
- Returns {String}

#### Example

`js
var hotp = require( 'hotp' )

var key = 'a very secret key'
var counter = 0

var token = hotp( key, counter, { digits: 8 })

console.log( token ) // > '78035651'
`

$3

#### hotp.totp( key[, options] )

- key {Buffer|String}
- options {Object}
- algorithm {Number} Default: 'sha1'
- digits {Number} Default: 6
- time {Number} Default: (Date.now() / 1000)
- timeStep {Number} Default: 30
- t0 {Number} Default: 0
- Returns {String}

#### Example

`js
var hotp = require( 'hotp' )

var key = 'a very secret key'
var token = hotp.totp( key, { digits: 8 })

console.log( token ) // > '86247382'
``

References

- RFC 4226, HOTP: An HMAC-Based One-Time Password Algorithm
- RFC 6238, TOTP: Time-Based One-Time Password Algorithm