/**
* @file MFKDF Persisted Factor Derivation
* @copyright Multifactor 2022 All Rights Reserved
*
* @description
* Use persisted factor for multi-factor key derivation
*
* @author Vivek Nair (https://nair.me) <[email protected]>
*/
/**
* Use a persisted MFDKF factor
*
* @example
* // setup 3-factor multi-factor derived key
* const setup = await mfkdf.setup.key([
* await mfkdf.setup.factors.password('password1', { id: 'password1' }),
* await mfkdf.setup.factors.password('password2', { id: 'password2' }),
* await mfkdf.setup.factors.password('password3', { id: 'password3' })
* ], {size: 8})
*
* // persist one of the factors
* const factor2 = setup.persistFactor('password2')
*
* // derive key with 2 factors
* const derived = await mfkdf.derive.key(setup.policy, {
* password1: mfkdf.derive.factors.password('password1'),
* password2: mfkdf.derive.factors.persisted(factor2),
* password3: mfkdf.derive.factors.password('password3')
* })
*
* setup.key.toString('hex') // -> 64587f2a0e65dc3c
* derived.key.toString('hex') // -> 64587f2a0e65dc3c
*
* @param {Buffer} share - The share corresponding to the persisted factor
* @returns {function(config:Object): Promise<MFKDFFactor>} Async function to generate MFKDF factor information
* @author Vivek Nair (https://nair.me) <[email protected]>
* @since 0.18.0
* @memberof derive.factors
*/
function persisted (share) {
if (!Buffer.isBuffer(share)) throw new TypeError('share must be a buffer')
return async (params) => {
return {
type: 'persisted',
data: share,
params: async () => {
return params
}
}
}
}
module.exports.persisted = persisted