The Tor Browser: browser/extensions/shumway/content/web/preview.js@6474c204b198 (annotated)

browser/extensions/shumway/content/web/preview.js@6474c204b198 (annotated)

browser/extensions/shumway/content/web/preview.js

Wed, 31 Dec 2014 06:09:35 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Wed, 31 Dec 2014 06:09:35 +0100
changeset 0: 6474c204b198
permissions: -rw-r--r--

Cloned upstream origin tor-browser at tor-browser-31.3.0esr-4.5-1-build1
revision ID fc1c9ff7c1b2defdbc039f12214767608f46423f for hacking purpose.

 /* -*- Mode: js; js-indent-level: 2; indent-tabs-mode: nil; tab-width: 2 -*- */
 /* vim: set shiftwidth=2 tabstop=2 autoindent cindent expandtab: */
 /*
  * Copyright 2013 Mozilla Foundation
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
  *     http://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
 // Extenstion communication object
 var FirefoxCom = (function FirefoxComClosure() {
   return {
     /**
      * Creates an event that the extension is listening for and will
      * synchronously respond to.
      * NOTE: It is reccomended to use request() instead since one day we may not
      * be able to synchronously reply.
      * @param {String} action The action to trigger.
      * @param {String} data Optional data to send.
      * @return {*} The response.
      */
     requestSync: function(action, data) {
       var request = document.createTextNode('');
       document.documentElement.appendChild(request);
       var sender = document.createEvent('CustomEvent');
       sender.initCustomEvent('shumway.message', true, false,
           {action: action, data: data, sync: true});
       request.dispatchEvent(sender);
       var response = sender.detail.response;
       document.documentElement.removeChild(request);
       return response;
     },
     /**
      * Creates an event that the extension is listening for and will
      * asynchronously respond by calling the callback.
      * @param {String} action The action to trigger.
      * @param {String} data Optional data to send.
      * @param {Function} callback Optional response callback that will be called
      * with one data argument.
      */
     request: function(action, data, callback) {
       var request = document.createTextNode('');
       request.setUserData('action', action, null);
       request.setUserData('data', data, null);
       request.setUserData('sync', false, null);
       if (callback) {
         request.setUserData('callback', callback, null);
         document.addEventListener('shumway.response', function listener(event) {
           var node = event.target,
               response = event.detail.response;
           document.documentElement.removeChild(node);
           document.removeEventListener('shumway.response', listener, false);
           return callback(response);
         }, false);
       }
       document.documentElement.appendChild(request);
       var sender = document.createEvent('CustomEvent');
       sender.initCustomEvent('shumway.message', true, false,
           {action: action, data: data, sync: false});
       return request.dispatchEvent(sender);
     }
   };
 })();
 function fallback() {
   FirefoxCom.requestSync('fallback', null)
 }
 var BYTES_TO_LOAD = 32768;
 var BYTES_TO_PARSE = 32768;
 function runSniffer() {
   var flashParams = JSON.parse(FirefoxCom.requestSync('getPluginParams', null));
   document.head.getElementsByTagName('base')[0].href = flashParams.baseUrl;
   movieUrl = flashParams.url;
   document.getElementById('playbutton').addEventListener('click', function() {
     switchToFullMode();
   });
   document.getElementById('fullmode').addEventListener('click', function() {
     switchToFullMode();
     return false;
   });
   document.getElementById('fallback').addEventListener('click', function() {
     fallback();
     return false;
   });
   FirefoxCom.requestSync('loadFile', {url: movieUrl, sessionId: 0, limit: BYTES_TO_LOAD});
 }
 var subscription, movieUrl, buffers = [];;
 addEventListener("message", function handlerMessage(e) {
   var args = e.data;
   switch (args.callback) {
     case "loadFile":
       if (args.sessionId != 0) {
         return;
       }
       switch (args.topic) {
         case "progress":
           buffers.push(args.array);
           break;
         case "error":
           console.error('Unable to download ' + movieUrl + ': ' + args.error);
           break;
         case "close":
           parseSwf();
           break;
       }
       break;
   }
 }, true);
 function inflateData(bytes, outputLength) {
   verifyDeflateHeader(bytes);
   var stream = new Stream(bytes, 2);
   var output = {
     data: new Uint8Array(outputLength),
     available: 0,
     completed: false
   };
   var state = {};
   // inflate while we can
   try {
     do {
       inflateBlock(stream, output, state);
     } while (!output.completed && stream.pos < stream.end
         && output.available < outputLength);
   } catch (e) {
     console.log('inflate aborted: ' + e);
   }
   return new Stream(output.data, 0, Math.min(output.available, outputLength));
 }
 function parseSwf() {
   var sum = 0;
   for (var i = 0; i < buffers.length; i++)
     sum += buffers[i].length;
   var data = new Uint8Array(sum), j = 0;
   for (var i = 0; i < buffers.length; i++) {
     data.set(buffers[i], j); j += buffers[i].length;
   }
   var backgroundColor;
   try {
     var magic1 = data[0];
     var magic2 = data[1];
     var magic3 = data[2];
     if ((magic1 !== 70 && magic1 !== 67) || magic2 !== 87 || magic3 !== 83)
       throw new Error('unsupported file format');
     var compressed = magic1 === 67;
     var stream = compressed ? inflateData(data.subarray(8), BYTES_TO_PARSE) :
         new Stream(data, 8, data.length - 8);
     var bytes = stream.bytes;
     var SWF_TAG_CODE_SET_BACKGROUND_COLOR = 9;
     var PREFETCH_SIZE = 17 /* RECT */ +
 /* Frames rate and count */;;
     stream.ensure(PREFETCH_SIZE);
     var rectFieldSize = bytes[stream.pos] >> 3;
     stream.pos += ((5 + 4 * rectFieldSize + 7) >> 3) + 4; // skipping other header fields
     // for now just sniffing background color
     while (stream.pos < stream.end &&
         !backgroundColor) {
       stream.ensure(2);
       var tagCodeAndLength = stream.getUint16(stream.pos, true);
       stream.pos += 2;
       var tagCode = tagCodeAndLength >> 6;
       var length = tagCodeAndLength & 0x3F;
       if (length == 0x3F) {
         stream.ensure(4);
         length = stream.getInt32(stream.pos, true);
         stream.pos += 4;
         if (length < 0) throw new Error('invalid length');
       }
       stream.ensure(length);
       switch (tagCode) {
         case SWF_TAG_CODE_SET_BACKGROUND_COLOR:
           backgroundColor = 'rgb(' + bytes[stream.pos] + ', ' +
               bytes[stream.pos + 1] + ', ' +
               bytes[stream.pos + 2] + ')';
           break;
       }
       stream.pos += length;
     }
   } catch (e) {
     console.log('parsing aborted: ' + e);
   }
   if (backgroundColor) {
     document.body.style.backgroundColor = backgroundColor;
   }
 }
 document.addEventListener('keydown', function (e) {
   if (e.keyCode == 119 && e.ctrlKey) { // Ctrl+F8
     window.location.replace("data:application/x-moz-playpreview;,application/x-shockwave-flash,full,paused=true");
   }
 }, false);
 function switchToFullMode() {
   window.location.replace("data:application/x-moz-playpreview;,application/x-shockwave-flash,full");
 }