modules/favicon.js

   1 /**
   2  * (C) Copyright 2008 Jeremy Maitin-Shepard
   3  *
   4  * Portions of this file were derived from Mozilla,
   5  * (C) Copyright 1998-2008 Mozilla Foundation.
   6  *
   7  * Use, modification, and distribution are subject to the terms specified in the
   8  * COPYING file.
   9 **/
  10
  11 in_module(null);
  12
  13 const favicon_service = Cc["@mozilla.org/browser/favicon-service;1"]
  14     .getService(Ci.nsIFaviconService);
  15
  16 define_variable("favicon_image_max_size", 1024,
  17     "Maximum (pixel) width and height of an image document that "+
  18     "is considered for use as a favicon.");
  19
  20 define_buffer_local_hook("buffer_favicon_change_hook");
  21 define_current_buffer_hook("current_buffer_favicon_change_hook", "buffer_favicon_change_hook");
  22
  23
  24 function favicon_set (buffer, icon_url) {
  25     buffer.favicon = icon_url.spec;
  26     favicon_service.setAndLoadFaviconForPage(buffer.current_uri,
  27                                              icon_url, false);
  28     buffer_favicon_change_hook.run(buffer);
  29 }
  30
  31
  32 function favicon_content_buffer_started_loading (buffer) {
  33     var old = buffer.favicon;
  34     buffer.favicon = null;
  35     if (old != null)
  36         buffer_favicon_change_hook.run(buffer);
  37 }
  38
  39
  40 function favicon_content_buffer_finished_loading (buffer) {
  41     if (buffer.favicon != null)
  42         return;
  43
  44     if (buffer.document instanceof Ci.nsIImageDocument) {
  45         var req = buffer.document.imageRequest;
  46         if (req && req.image &&
  47             req.image.width <= favicon_image_max_size  &&
  48             req.image.height <= favicon_image_max_size)
  49         {
  50             favicon_set(buffer, buffer.current_uri);
  51             return;
  52         }
  53     }
  54
  55     var uri = buffer.current_uri;
  56     // Only load favicons for http and https
  57     if (!uri.schemeIs("http") && !uri.schemeIs("https"))
  58         return;
  59
  60     var icon_url = make_uri(uri.prePath + "/favicon.ico");
  61     if (!favicon_service.isFailedFavicon(icon_url))
  62         favicon_set(buffer, icon_url);
  63 }
  64
  65
  66 function favicon_content_buffer_dom_link_added (buffer, event) {
  67     var link = event.originalTarget;
  68     if (!link || !link.ownerDocument || !link.rel || !link.href ||
  69         link.ownerDocument != buffer.document)
  70     {
  71         return;
  72     }
  73     var rel = link.rel.toLowerCase();
  74     var rel_strings = rel.split(/\s+/);
  75     if (rel_strings.indexOf("icon") == -1)
  76         return;
  77
  78     /* FIXME: perhaps worry about newURI throwing an exception */
  79     var target_doc = link.ownerDocument;
  80     var ios = Cc["@mozilla.org/network/io-service;1"]
  81         .getService(Ci.nsIIOService);
  82     var uri = ios.newURI(link.href, target_doc.characterSet, null);
  83
  84     if (favicon_service.isFailedFavicon(uri))
  85         return;
  86
  87     // Verify that the load of this icon is legal.
  88     // error pages can load their favicon, to be on the safe side,
  89     // only allow chrome:// favicons
  90     const about_neterr = "about:neterror?";
  91     if (target_doc.documentURI.substr(0, about_neterr.length) != about_neterr
  92         || !uri.schemeIs("chrome"))
  93     {
  94         var ssm = Cc["@mozilla.org/scriptsecuritymanager;1"]
  95             .getService(Ci.nsIScriptSecurityManager);
  96         try {
  97             ssm.checkLoadURIWithPrincipal(
  98                 target_doc.nodePrincipal, uri,
  99                 Ci.nsIScriptSecurityManager.DISALLOW_SCRIPT);
 100         } catch(e) {
 101             return;
 102         }
 103     }
 104
 105     try {
 106     } catch(e) {
 107         return; // Refuse to load if we can't do a security check.
 108     }
 109
 110     // Security says okay, now ask content policy
 111     var content_policy_service = Cc["@mozilla.org/layout/content-policy;1"]
 112         .getService(Ci.nsIContentPolicy);
 113     if (content_policy_service.shouldLoad(Ci.nsIContentPolicy.TYPE_IMAGE,
 114                                           uri, target_doc.documentURIObject,
 115                                           link, link.type, null)
 116         != Ci.nsIContentPolicy.ACCEPT)
 117     {
 118         return;
 119     }
 120
 121     favicon_set(buffer, uri);
 122 }
 123
 124
 125 add_hook("content_buffer_started_loading_hook",
 126          favicon_content_buffer_started_loading);
 127
 128 add_hook("content_buffer_finished_loading_hook",
 129          favicon_content_buffer_finished_loading);
 130
 131 add_hook("content_buffer_dom_link_added_hook",
 132          favicon_content_buffer_dom_link_added);
 133
 134 provide("favicon");