michael@0: /* -*- Mode: js2; js2-basic-offset: 2; indent-tabs-mode: nil; -*- */
michael@0: /* vim: set ft=javascript ts=2 et sw=2 tw=80: */
michael@0: /* This Source Code Form is subject to the terms of the Mozilla Public
michael@0:  * License, v. 2.0. If a copy of the MPL was not distributed with this file,
michael@0:  * You can obtain one at http://mozilla.org/MPL/2.0/. */
michael@0: 
michael@0: "use strict";
michael@0: 
michael@0: 
michael@0: const Cu = Components.utils;
michael@0: const Ci = Components.interfaces;
michael@0: const Cc = Components.classes;
michael@0: const Cr = Components.results;
michael@0: 
michael@0: Cu.import("resource://gre/modules/XPCOMUtils.jsm");
michael@0: Cu.import("resource://gre/modules/Services.jsm");
michael@0: Cu.import("resource://gre/modules/identity/LogUtils.jsm");
michael@0: 
michael@0: XPCOMUtils.defineLazyServiceGetter(this,
michael@0:                                    "IdentityCryptoService",
michael@0:                                    "@mozilla.org/identity/crypto-service;1",
michael@0:                                    "nsIIdentityCryptoService");
michael@0: 
michael@0: this.EXPORTED_SYMBOLS = ["jwcrypto"];
michael@0: 
michael@0: const ALGORITHMS = { RS256: "RS256", DS160: "DS160" };
michael@0: const DURATION_MS = 1000 * 60 * 2; // 2 minutes default assertion lifetime
michael@0: 
michael@0: function log(...aMessageArgs) {
michael@0:   Logger.log.apply(Logger, ["jwcrypto"].concat(aMessageArgs));
michael@0: }
michael@0: 
michael@0: function generateKeyPair(aAlgorithmName, aCallback) {
michael@0:   log("Generate key pair; alg =", aAlgorithmName);
michael@0: 
michael@0:   IdentityCryptoService.generateKeyPair(aAlgorithmName, function(rv, aKeyPair) {
michael@0:     if (!Components.isSuccessCode(rv)) {
michael@0:       return aCallback("key generation failed");
michael@0:     }
michael@0: 
michael@0:     var publicKey;
michael@0: 
michael@0:     switch (aKeyPair.keyType) {
michael@0:      case ALGORITHMS.RS256:
michael@0:       publicKey = {
michael@0:         algorithm: "RS",
michael@0:         exponent:  aKeyPair.hexRSAPublicKeyExponent,
michael@0:         modulus:   aKeyPair.hexRSAPublicKeyModulus
michael@0:       };
michael@0:       break;
michael@0: 
michael@0:      case ALGORITHMS.DS160:
michael@0:       publicKey = {
michael@0:         algorithm: "DS",
michael@0:         y: aKeyPair.hexDSAPublicValue,
michael@0:         p: aKeyPair.hexDSAPrime,
michael@0:         q: aKeyPair.hexDSASubPrime,
michael@0:         g: aKeyPair.hexDSAGenerator
michael@0:       };
michael@0:       break;
michael@0: 
michael@0:     default:
michael@0:       return aCallback("unknown key type");
michael@0:     }
michael@0: 
michael@0:     let keyWrapper = {
michael@0:       serializedPublicKey: JSON.stringify(publicKey),
michael@0:       _kp: aKeyPair
michael@0:     };
michael@0: 
michael@0:     return aCallback(null, keyWrapper);
michael@0:   });
michael@0: }
michael@0: 
michael@0: function sign(aPayload, aKeypair, aCallback) {
michael@0:   aKeypair._kp.sign(aPayload, function(rv, signature) {
michael@0:     if (!Components.isSuccessCode(rv)) {
michael@0:       log("ERROR: signer.sign failed");
michael@0:       return aCallback("Sign failed");
michael@0:     }
michael@0:     log("signer.sign: success");
michael@0:     return aCallback(null, signature);
michael@0:   });
michael@0: }
michael@0: 
michael@0: function jwcryptoClass()
michael@0: {
michael@0: }
michael@0: 
michael@0: jwcryptoClass.prototype = {
michael@0:   /*
michael@0:    * Determine the expiration of the assertion.  Returns expiry date
michael@0:    * in milliseconds as integer.
michael@0:    *
michael@0:    * @param localtimeOffsetMsec (optional)
michael@0:    *        The number of milliseconds that must be added to the local clock
michael@0:    *        for it to agree with the server.  For example, if the local clock
michael@0:    *        if two minutes fast, localtimeOffsetMsec would be -120000
michael@0:    *
michael@0:    * @param now (options)
michael@0:    *        Current date in milliseconds.  Useful for mocking clock
michael@0:    *        skew in testing.
michael@0:    */
michael@0:   getExpiration: function(duration=DURATION_MS, localtimeOffsetMsec=0, now=Date.now()) {
michael@0:     return now + localtimeOffsetMsec + duration;
michael@0:   },
michael@0: 
michael@0:   isCertValid: function(aCert, aCallback) {
michael@0:     // XXX check expiration, bug 769850
michael@0:     aCallback(true);
michael@0:   },
michael@0: 
michael@0:   generateKeyPair: function(aAlgorithmName, aCallback) {
michael@0:     log("generating");
michael@0:     generateKeyPair(aAlgorithmName, aCallback);
michael@0:   },
michael@0: 
michael@0:   /*
michael@0:    * Generate an assertion and return it through the provided callback.
michael@0:    *
michael@0:    * @param aCert
michael@0:    *        Identity certificate
michael@0:    *
michael@0:    * @param aKeyPair
michael@0:    *        KeyPair object
michael@0:    *
michael@0:    * @param aAudience
michael@0:    *        Audience of the assertion
michael@0:    *
michael@0:    * @param aOptions (optional)
michael@0:    *        Can include:
michael@0:    *        {
michael@0:    *          localtimeOffsetMsec: <clock offset in milliseconds>,
michael@0:    *          now: <current date in milliseconds>
michael@0:    *          duration: <validity duration for this assertion in milliseconds>
michael@0:    *        }
michael@0:    *
michael@0:    *        localtimeOffsetMsec is the number of milliseconds that need to be
michael@0:    *        added to the local clock time to make it concur with the server.
michael@0:    *        For example, if the local clock is two minutes fast, the offset in
michael@0:    *        milliseconds would be -120000.
michael@0:    *
michael@0:    * @param aCallback
michael@0:    *        Function to invoke with resulting assertion.  Assertion
michael@0:    *        will be string or null on failure.
michael@0:    */
michael@0:   generateAssertion: function(aCert, aKeyPair, aAudience, aOptions, aCallback) {
michael@0:     if (typeof aOptions == "function") {
michael@0:       aCallback = aOptions;
michael@0:       aOptions = { };
michael@0:     }
michael@0: 
michael@0:     // for now, we hack the algorithm name
michael@0:     // XXX bug 769851
michael@0:     var header = {"alg": "DS128"};
michael@0:     var headerBytes = IdentityCryptoService.base64UrlEncode(
michael@0:                           JSON.stringify(header));
michael@0: 
michael@0:     var payload = {
michael@0:       exp: this.getExpiration(
michael@0:                aOptions.duration, aOptions.localtimeOffsetMsec, aOptions.now),
michael@0:       aud: aAudience
michael@0:     };
michael@0:     var payloadBytes = IdentityCryptoService.base64UrlEncode(
michael@0:                           JSON.stringify(payload));
michael@0: 
michael@0:     log("payload bytes", payload, payloadBytes);
michael@0:     sign(headerBytes + "." + payloadBytes, aKeyPair, function(err, signature) {
michael@0:       if (err)
michael@0:         return aCallback(err);
michael@0: 
michael@0:       var signedAssertion = headerBytes + "." + payloadBytes + "." + signature;
michael@0:       return aCallback(null, aCert + "~" + signedAssertion);
michael@0:     });
michael@0:   }
michael@0: 
michael@0: };
michael@0: 
michael@0: this.jwcrypto = new jwcryptoClass();
michael@0: this.jwcrypto.ALGORITHMS = ALGORITHMS;