| var Buffer = require('safe-buffer').Buffer |
| |
| var checkParameters = require('./precondition') |
| var defaultEncoding = require('./default-encoding') |
| var sync = require('./sync') |
| var toBuffer = require('./to-buffer') |
| |
| var ZERO_BUF |
| var subtle = global.crypto && global.crypto.subtle |
| var toBrowser = { |
| sha: 'SHA-1', |
| 'sha-1': 'SHA-1', |
| sha1: 'SHA-1', |
| sha256: 'SHA-256', |
| 'sha-256': 'SHA-256', |
| sha384: 'SHA-384', |
| 'sha-384': 'SHA-384', |
| 'sha-512': 'SHA-512', |
| sha512: 'SHA-512' |
| } |
| var checks = [] |
| function checkNative (algo) { |
| if (global.process && !global.process.browser) { |
| return Promise.resolve(false) |
| } |
| if (!subtle || !subtle.importKey || !subtle.deriveBits) { |
| return Promise.resolve(false) |
| } |
| if (checks[algo] !== undefined) { |
| return checks[algo] |
| } |
| ZERO_BUF = ZERO_BUF || Buffer.alloc(8) |
| var prom = browserPbkdf2(ZERO_BUF, ZERO_BUF, 10, 128, algo) |
| .then(function () { |
| return true |
| }).catch(function () { |
| return false |
| }) |
| checks[algo] = prom |
| return prom |
| } |
| var nextTick |
| function getNextTick () { |
| if (nextTick) { |
| return nextTick |
| } |
| if (global.process && global.process.nextTick) { |
| nextTick = global.process.nextTick |
| } else if (global.queueMicrotask) { |
| nextTick = global.queueMicrotask |
| } else if (global.setImmediate) { |
| nextTick = global.setImmediate |
| } else { |
| nextTick = global.setTimeout |
| } |
| return nextTick |
| } |
| function browserPbkdf2 (password, salt, iterations, length, algo) { |
| return subtle.importKey( |
| 'raw', password, { name: 'PBKDF2' }, false, ['deriveBits'] |
| ).then(function (key) { |
| return subtle.deriveBits({ |
| name: 'PBKDF2', |
| salt: salt, |
| iterations: iterations, |
| hash: { |
| name: algo |
| } |
| }, key, length << 3) |
| }).then(function (res) { |
| return Buffer.from(res) |
| }) |
| } |
| |
| function resolvePromise (promise, callback) { |
| promise.then(function (out) { |
| getNextTick()(function () { |
| callback(null, out) |
| }) |
| }, function (e) { |
| getNextTick()(function () { |
| callback(e) |
| }) |
| }) |
| } |
| module.exports = function (password, salt, iterations, keylen, digest, callback) { |
| if (typeof digest === 'function') { |
| callback = digest |
| digest = undefined |
| } |
| |
| digest = digest || 'sha1' |
| var algo = toBrowser[digest.toLowerCase()] |
| |
| if (!algo || typeof global.Promise !== 'function') { |
| getNextTick()(function () { |
| var out |
| try { |
| out = sync(password, salt, iterations, keylen, digest) |
| } catch (e) { |
| return callback(e) |
| } |
| callback(null, out) |
| }) |
| return |
| } |
| |
| checkParameters(iterations, keylen) |
| password = toBuffer(password, defaultEncoding, 'Password') |
| salt = toBuffer(salt, defaultEncoding, 'Salt') |
| if (typeof callback !== 'function') throw new Error('No callback provided to pbkdf2') |
| |
| resolvePromise(checkNative(algo).then(function (resp) { |
| if (resp) return browserPbkdf2(password, salt, iterations, keylen, algo) |
| |
| return sync(password, salt, iterations, keylen, digest) |
| }), callback) |
| } |