Merge pull request #47 from southworkscom/master

PNG images validation in icon parsing

Author: boyofgreen

lib/manifestTools/manifestCreator/scrapers/icojs/src/ico.js

@@ -21,6 +21,71 @@ var range = function(n) {
 * @class ICO
 */
 
+/**
+ * Generate the hexadecimal value from an arrayBuffer.
+ * @memberof ICO
+ * @param {ArrayBuffer} buffer The ArrayBuffer object contain the TypedArray of a ICO file.
+ * @returns {String} The hexadecimal value.
+ */
+function buf2hex(buffer) { // buffer is an ArrayBuffer
+  return Array.prototype.map.call(new Uint8Array(buffer), x => ('00' + x.toString(16)).slice(-2)).join('');
+}
+
+/**
+ * Creates a PNG image object using the createIcon method.
+ * @memberof ICO
+ * @param {Int} index The image index.
+ * @param {ArrayBuffer} buffer The ArrayBuffer object contain the TypedArray of a ICO file.
+ * @returns {Object} PNG icon object.
+ */
+
+function createPng(index, buffer) {
+  var dv = new DataView(buffer);
+
+  var icoWidth = dv.getUint8(6 + (index * 16)) || 256;
+  var icoHeight = dv.getUint8(7 + (index * 16)) || 256;
+  var icoOffset = dv.getUint32(18 + (index * 16), true);
+  var icoBit = dv.getUint8((icoOffset + 16) + 8, true);
+  var endImage = (buf2hex(buffer.slice(icoOffset, buffer.byteLength))).indexOf("49454e44");
+  var imgBuffer = buffer.slice(icoOffset, icoOffset + endImage);
+  
+  return createIcon(icoBit, icoWidth, icoHeight, imgBuffer);
+}
+
+/**
+ * Validates if the image is PNG.
+ * @memberof ICO
+ * @param {Int} index The image index.
+ * @param {ArrayBuffer} buffer The ArrayBuffer object contain the TypedArray of a ICO file.
+ * @returns {Boolean} True if the image is PNG.
+ */
+
+function isPNG(index, buffer) {
+  var icoDv = new DataView(buffer);
+  var startImage = icoDv.getUint32(18 + (index * 16), true);
+  var bufferSlice = buf2hex(buffer.slice(startImage, startImage + 4))
+  return (bufferSlice === "89504e47");
+}
+
+
+/**
+ * Creates an image object.
+ * @memberof ICO
+ * @param {Int} bit The image bit depth.
+ * @param {Int} width The image width.
+ * @param {Int} height The image height.
+ * @param {ArrayBuffer} buffer The ArrayBuffer object contain the TypedArray of a ICO file.
+ * @returns {Object} An icon object.
+ */
+function createIcon(bit, width, height, buffer) {
+  return {
+    bit:  bit,
+    width: width,
+    height: height,
+    buffer: buffer
+  }
+}
+
 var factory = function(config) {
   var previousICO = global.ICO;
   var Image = config.Image;
@@ -38,47 +103,49 @@ var factory = function(config) {
      *   * `buffer` **ArrayBuffer** - Image buffer.
      */
     parse: function(buffer, mime) {
+
       var icoDv = new DataView(buffer);
       if (icoDv.getUint16(0, true) !== 0 || icoDv.getUint16(2, true) !== 1) {
         var deferred = Q.defer();
         return deferred.reject(new Error('buffer is not ico'));
       }
-
-      // make single image icon
-      // let idCount = icoDv.getUint16(4, true);
-      return Q.all(range(icoDv.getUint16(4, true)).map(function(i) {
-        var ico = extractOne(buffer, i);
-        var image = {
-          width: ico.width,
-          height: ico.height
-        };
-
-        switch (ico.bit) { // eslint-disable-line default-case
-          case 1:
-            image.data = imageData.from1bit(ico);
-            break;
-          case 4:
-            image.data = imageData.from4bit(ico);
-            break;
-          case 8:
-            image.data = imageData.from8bit(ico);
-            break;
-          case 24:
-            image.data = imageData.from24bit(ico);
-            break;
-          case 32:
-            image.data = imageData.from32bit(ico);
-            break;
-        }
-
-        return Image.encode(image, mime).then(function(pngBuffer) {
-          return {
-            bit: ico.bit,
-            width: ico.width,
-            height: ico.height,
-            buffer: pngBuffer
-          };
-        });
+      
+      return Q.all(range(icoDv.getUint16(4, true))
+              .map(function(i) {
+                
+                if(isPNG(i,buffer)){
+                  var deferred = Q.defer();
+                  deferred.resolve(createPng(i,buffer));
+                  return deferred.promise;
+                } else {
+                  var ico = extractOne(buffer, i);
+                  var image = {
+                    width: ico.width,
+                    height: ico.height
+                  };
+                  
+                  switch (ico.bit) { // eslint-disable-line default-case
+                    case 1:
+                    image.data = imageData.from1bit(ico);
+                    break;
+                    case 4:
+                    image.data = imageData.from4bit(ico);
+                    break;
+                    case 8:
+                    image.data = imageData.from8bit(ico);
+                    break;
+                    case 24:
+                    image.data = imageData.from24bit(ico);
+                    break;
+                    case 32:
+                    image.data = imageData.from32bit(ico);
+                    break;
+                  }
+                  
+                  return Image.encode(image, mime).then(function(pngBuffer) {
+                    return createIcon(ico.bit, ico.width, ico.height, pngBuffer);
+                  });
+                }
       }));
     },
     /**