var md5 = require('create-hash/md5') var RIPEMD160 = require('ripemd160') var sha = require('sha.js') var checkParameters = require('./precondition') var defaultEncoding = require('./default-encoding') var Buffer = require('safe-buffer').Buffer var ZEROS = Buffer.alloc(128) var sizes = { md5: 16, sha1: 20, sha224: 28, sha256: 32, sha384: 48, sha512: 64, rmd160: 20, ripemd160: 20 } function Hmac (alg, key, saltLen) { var hash = getDigest(alg) var blocksize = (alg === 'sha512' || alg === 'sha384') ? 128 : 64 if (key.length > blocksize) { key = hash(key) } else if (key.length < blocksize) { key = Buffer.concat([key, ZEROS], blocksize) } var ipad = Buffer.allocUnsafe(blocksize + sizes[alg]) var opad = Buffer.allocUnsafe(blocksize + sizes[alg]) for (var i = 0; i < blocksize; i++) { ipad[i] = key[i] ^ 0x36 opad[i] = key[i] ^ 0x5C } var ipad1 = Buffer.allocUnsafe(blocksize + saltLen + 4) ipad.copy(ipad1, 0, 0, blocksize) this.ipad1 = ipad1 this.ipad2 = ipad this.opad = opad this.alg = alg this.blocksize = blocksize this.hash = hash this.size = sizes[alg] } Hmac.prototype.run = function (data, ipad) { data.copy(ipad, this.blocksize) var h = this.hash(ipad) h.copy(this.opad, this.blocksize) return this.hash(this.opad) } function getDigest (alg) { function shaFunc (data) { return sha(alg).update(data).digest() } function rmd160Func (data) { return new RIPEMD160().update(data).digest() } if (alg === 'rmd160' || alg === 'ripemd160') return rmd160Func if (alg === 'md5') return md5 return shaFunc } function pbkdf2 (password, salt, iterations, keylen, digest) { checkParameters(password, salt, iterations, keylen) if (!Buffer.isBuffer(password)) password = Buffer.from(password, defaultEncoding) if (!Buffer.isBuffer(salt)) salt = Buffer.from(salt, defaultEncoding) digest = digest || 'sha1' var hmac = new Hmac(digest, password, salt.length) var DK = Buffer.allocUnsafe(keylen) var block1 = Buffer.allocUnsafe(salt.length + 4) salt.copy(block1, 0, 0, salt.length) var destPos = 0 var hLen = sizes[digest] var l = Math.ceil(keylen / hLen) for (var i = 1; i <= l; i++) { block1.writeUInt32BE(i, salt.length) var T = hmac.run(block1, hmac.ipad1) var U = T for (var j = 1; j < iterations; j++) { U = hmac.run(U, hmac.ipad2) for (var k = 0; k < hLen; k++) T[k] ^= U[k] } T.copy(DK, destPos) destPos += hLen } return DK } module.exports = pbkdf2