old-keypairs.js/index.js

135 lines
3.7 KiB
JavaScript

;(function (exports) {
'use strict';
var PromiseA;
try {
/*global Promise*/
PromiseA = Promise;
} catch(e) {
PromiseA = require('bluebird');
}
// https://stackoverflow.com/questions/40314257/export-webcrypto-key-to-pem-format
function derToPem(keydata, pemName, privacy){
var keydataS = arrayBufferToString(keydata);
var keydataB64 = window.btoa(keydataS);
var keydataB64Pem = formatAsPem(keydataB64, pemName, privacy);
return keydataB64Pem;
}
function arrayBufferToString( buffer ) {
var binary = [];
var bytes = new Uint8Array( buffer );
var len = bytes.byteLength;
for (var i = 0; i < len; i++) {
binary.push(String.fromCharCode( bytes[ i ] ));
}
return binary.join('');
}
function formatAsPem(str, pemName, privacy) {
var privstr = (privacy ? privacy + ' ' : '');
var finalString = '-----BEGIN ' + pemName + ' ' + privstr + 'KEY-----\n';
while (str.length > 0) {
finalString += str.substring(0, 64) + '\n';
str = str.substring(64);
}
finalString = finalString + '-----END ' + pemName + ' ' + privstr + 'KEY-----';
return finalString;
}
var Keypairs = exports.Keypairs = {
generate: function(opts) {
if (!opts) { opts = {}; }
if (!opts.type) { opts.type = 'EC'; }
var supported = [ 'EC', 'RSA' ];
if (-1 === supported.indexOf(opts.type)) {
return PromiseA.reject(new Error("'" + opts.type + "' not implemented. Try one of " + supported.join(', ')));
}
if ('EC' === opts.type) {
return Keypairs._generateEc(opts);
}
if ('RSA' === opts.type) {
return Keypairs._generateRsa(opts);
}
}
, _generateEc: function (opts) {
if (!opts.namedCurve) { opts.namedCurve = 'P-256'; }
if ('P-256' !== opts.namedCurve) {
console.warn("'" + opts.namedCurve + "' is not supported, but it _might_ happen to work anyway.");
}
// https://github.com/diafygi/webcrypto-examples#ecdsa---generatekey
var extractable = true;
return window.crypto.subtle.generateKey(
{ name: "ECDSA", namedCurve: opts.namedCurve }
, extractable
, [ 'sign', 'verify' ]
).then(function (result) {
return window.crypto.subtle.exportKey(
"jwk"
, result.privateKey
).then(function (jwk) {
return window.crypto.subtle.exportKey(
"pkcs8"
, result.privateKey
).then(function (keydata) {
return {
type: 'EC'
, privateJwk: jwk
, privatePem: derToPem(keydata, 'EC', 'PRIVATE')
};
});
});
});
}
, _generateRsa: function (opts) {
if (!opts.bitlength) { opts.bitlength = 2048; }
if (-1 === [ 2048, 4096 ].indexOf(opts.bitlength)) {
return PromiseA.reject("opts.bitlength = (" + typeof opts.bitlength + ") " + opts.bitlength + ": Are you serious?");
}
// https://github.com/diafygi/webcrypto-examples#rsa---generatekey
var extractable = true;
return window.crypto.subtle.generateKey(
{ name: "RSASSA-PKCS1-v1_5"
, modulusLength: opts.bitlength
, publicExponent: new Uint8Array([0x01, 0x00, 0x01])
, hash: { name: "SHA-256" }
}
, extractable
, [ 'sign', 'verify' ]
).then(function (result) {
return window.crypto.subtle.exportKey(
"jwk"
, result.privateKey
).then(function (jwk) {
return window.crypto.subtle.exportKey(
"pkcs8"
, result.privateKey
).then(function (keydata) {
return {
type: 'RSA'
, privateJwk: jwk
, privatePem: derToPem(keydata, 'RSA', 'PRIVATE')
};
});
});
});
}
};
}('undefined' === typeof module ? window : module.exports));
// How we might use this
// var Keypairs = require('keypairs').Keypairs