/**
* @file MFKDF Question Factor Derivation
* @copyright Multifactor 2022 All Rights Reserved
*
* @description
* Derive question factor for multi-factor key derivation
*
* @author Vivek Nair (https://nair.me) <[email protected]>
*/
const zxcvbn = require('zxcvbn')
/**
* Derive an MFKDF Security Question factor
*
* @example
* // setup key with security question factor
* const setup = await mfkdf.setup.key([
* await mfkdf.setup.factors.question('Fido')
* ], {size: 8})
*
* // derive key with security question factor
* const derive = await mfkdf.derive.key(setup.policy, {
* question: mfkdf.derive.factors.question('Fido')
* })
*
* setup.key.toString('hex') // -> 01d0c7236adf2516
* derive.key.toString('hex') // -> 01d0c7236adf2516
*
* @param {string} answer - The answer from which to derive an MFKDF factor
* @returns {function(config:Object): Promise<MFKDFFactor>} Async function to generate MFKDF factor information
* @author Vivek Nair (https://nair.me) <[email protected]>
* @since 1.0.0
* @memberof derive.factors
*/
function question (answer) {
if (typeof answer !== 'string') throw new TypeError('answer must be a string')
if (answer.length === 0) throw new RangeError('answer cannot be empty')
answer = answer.toLowerCase().replace(/[^0-9a-z ]/gi, '').trim()
const strength = zxcvbn(answer)
return async (params) => {
return {
type: 'question',
data: Buffer.from(answer),
params: async () => {
return params
},
output: async () => {
return { strength }
}
}
}
}
module.exports.question = question