Cleanup RSA and util code

.jshintrc

@@ -29,6 +29,9 @@
     "before": true,
     "beforeEach": true,
     "after": true,
-    "afterEach": true
+    "afterEach": true,
+    "escape": true,
+    "unescape": true,
+    "asmCrypto": true
   }
 }

src/crypto/public_key/rsa.js

@@ -24,6 +24,8 @@
  * @module crypto/public_key/rsa
  */
 
+'use strict';
+
 var BigInteger = require('./jsbn.js'),
   util = require('../../util.js'),
   random = require('../random.js'),
@@ -119,7 +121,7 @@ function RSA() {
 
   // "empty" RSA key constructor
 
-  function keyObject() {
+  function KeyObject() {
     this.n = null;
     this.e = 0;
     this.ee = null;
@@ -167,8 +169,8 @@ function RSA() {
         };
 
         keys = webCrypto.generateKey(keyGenOpt, true, ['sign', 'verify']);
-        if (!(typeof keys.then === 'function')) { // IE11 KeyOperation
+        if (typeof keys.then !== 'function') { // IE11 KeyOperation
-          keys = convertKeyOperation(keys, 'Error generating RSA key pair.');
+          keys = util.promisifyIE11Op(keys, 'Error generating RSA key pair.');
         }
       }
 
@@ -185,15 +187,15 @@ function RSA() {
       // export the generated keys as JsonWebKey (JWK)
       // https://tools.ietf.org/html/draft-ietf-jose-json-web-key-33
       var key = webCrypto.exportKey('jwk', keypair.privateKey);
-      if (!(typeof key.then === 'function')) { // IE11 KeyOperation
+      if (typeof key.then !== 'function') { // IE11 KeyOperation
-        key = convertKeyOperation(key, 'Error exporting RSA key pair.');
+        key = util.promisifyIE11Op(key, 'Error exporting RSA key pair.');
       }
       return key;
     }
 
     function decodeKey(jwk) {
       // map JWK parameters to local BigInteger type system
-      var key = new keyObject();
+      var key = new KeyObject();
       key.n = toBigInteger(jwk.n);
       key.ee = new BigInteger(E, 16);
       key.d = toBigInteger(jwk.d);
@@ -210,23 +212,12 @@ function RSA() {
       return key;
     }
 
-    function convertKeyOperation(keyop, errmsg) {
-      return new Promise(function(resolve, reject) {
-        keyop.onerror = function (err) { 
-          reject(new Error(errmsg));
-        };
-        keyop.oncomplete = function (e) {
-          resolve(e.target.result);
-        };
-      });
-    }
-
     //
     // JS code
     //
 
     return new Promise(function(resolve) {
-      var key = new keyObject();
+      var key = new KeyObject();
       var rng = new SecureRandom();
       var qs = B >> 1;
       key.e = parseInt(E, 16);
@@ -235,14 +226,16 @@ function RSA() {
       for (;;) {
         for (;;) {
           key.p = new BigInteger(B - qs, 1, rng);
-          if (key.p.subtract(BigInteger.ONE).gcd(key.ee).compareTo(BigInteger.ONE) === 0 && key.p.isProbablePrime(10))
+          if (key.p.subtract(BigInteger.ONE).gcd(key.ee).compareTo(BigInteger.ONE) === 0 && key.p.isProbablePrime(10)) {
             break;
           }
+        }
         for (;;) {
           key.q = new BigInteger(qs, 1, rng);
-          if (key.q.subtract(BigInteger.ONE).gcd(key.ee).compareTo(BigInteger.ONE) === 0 && key.q.isProbablePrime(10))
+          if (key.q.subtract(BigInteger.ONE).gcd(key.ee).compareTo(BigInteger.ONE) === 0 && key.q.isProbablePrime(10)) {
             break;
           }
+        }
         if (key.p.compareTo(key.q) <= 0) {
           var t = key.p;
           key.p = key.q;
@@ -270,7 +263,7 @@ function RSA() {
   this.verify = verify;
   this.sign = sign;
   this.generate = generate;
-  this.keyObject = keyObject;
+  this.keyObject = KeyObject;
 }
 
 module.exports = RSA;

src/util.js

@@ -69,12 +69,15 @@ module.exports = {
     var i = 0;
     while (c < e) {
       h = str.charCodeAt(c++).toString(16);
-      while (h.length < 2) h = "0" + h;
+      while (h.length < 2) {
+        h = "0" + h;
+      }
       r.push(" " + h);
       i++;
-      if (i % 32 === 0)
+      if (i % 32 === 0) {
         r.push("\n           ");
       }
+    }
     return r.join('');
   },
 
@@ -84,15 +87,18 @@ module.exports = {
    * @return {String} String containing the hexadecimal values
    */
   hexstrdump: function (str) {
-    if (str === null)
+    if (str === null) {
       return "";
+    }
     var r = [];
     var e = str.length;
     var c = 0;
     var h;
     while (c < e) {
       h = str.charCodeAt(c++).toString(16);
-      while (h.length < 2) h = "0" + h;
+      while (h.length < 2) {
+        h = "0" + h;
+      }
       r.push("" + h);
     }
     return r.join('');
@@ -105,8 +111,9 @@ module.exports = {
    */
   hex2bin: function (hex) {
     var str = '';
-    for (var i = 0; i < hex.length; i += 2)
+    for (var i = 0; i < hex.length; i += 2) {
       str += String.fromCharCode(parseInt(hex.substr(i, 2), 16));
+    }
     return str;
   },
 
@@ -122,7 +129,9 @@ module.exports = {
     var h;
     while (c < e) {
       h = str[c++].toString(16);
-      while (h.length < 2) h = "0" + h;
+      while (h.length < 2) {
+        h = "0" + h;
+      }
       r.push("" + h);
     }
     return r.join('');
@@ -189,7 +198,7 @@ module.exports = {
   str2Uint8Array: function (str) {
 
     // Uncomment for debugging
-    if(!(typeof str === 'string') && !String.prototype.isPrototypeOf(str)) {
+    if(typeof str !== 'string' && !String.prototype.isPrototypeOf(str)) {
       throw new Error('str2Uint8Array: Data must be in the form of a string');
     }
 
@@ -342,8 +351,9 @@ module.exports = {
 
   getLeftNBits: function (string, bitcount) {
     var rest = bitcount % 8;
-    if (rest === 0)
+    if (rest === 0) {
       return string.substring(0, bitcount / 8);
+    }
     var bytes = (bitcount - rest) / 8 + 1;
     var result = string.substring(0, bytes);
     return this.shiftRight(result, 8 - rest); // +String.fromCharCode(string.charCodeAt(bytes -1) << (8-rest) & 0xFF);
@@ -357,17 +367,18 @@ module.exports = {
    * @return {String} Resulting string.
    */
   shiftRight: function (value, bitcount) {
-    var temp = util.str2bin(value);
+    var temp = this.str2bin(value);
     if (bitcount % 8 !== 0) {
       for (var i = temp.length - 1; i >= 0; i--) {
         temp[i] >>= bitcount % 8;
-        if (i > 0)
+        if (i > 0) {
           temp[i] |= (temp[i - 1] << (8 - (bitcount % 8))) & 0xFF;
         }
+      }
     } else {
       return value;
     }
-    return util.bin2str(temp);
+    return this.bin2str(temp);
   },
 
   /**
@@ -413,5 +424,40 @@ module.exports = {
         return window.msCrypto.subtle;
       }
     }
-  }
+  },
+
+  /**
+   * Wraps a generic synchronous function in an ES6 Promise.
+   * @param  {Function} fn  The function to be wrapped
+   * @return {Function}     The function wrapped in a Promise
+   */
+  promisify: function(fn) {
+    return function() {
+      var args = arguments;
+      return new Promise(function(resolve) {
+        var result = fn.apply(null, args);
+        resolve(result);
+      });
+    };
+  },
+
+  /**
+   * Converts an IE11 web crypro api result to a promise.
+   *   This is required since IE11 implements an old version of the
+   *   Web Crypto specification that does not use promises.
+   * @param  {Object} cryptoOp The return value of an IE11 web cryptro api call
+   * @param  {String} errmsg   An error message for a specific operation
+   * @return {Promise}         The resulting Promise
+   */
+  promisifyIE11Op: function(cryptoOp, errmsg) {
+    return new Promise(function(resolve, reject) {
+      cryptoOp.onerror = function () {
+        reject(new Error(errmsg));
+      };
+      cryptoOp.oncomplete = function (e) {
+        resolve(e.target.result);
+      };
+    });
+  }
+
 };