Gmail mails get modified upon send due to certain extensions

chrome/renderer/extensions/user_script_slave.cc

 // Copyright (c) 2011 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "chrome/renderer/extensions/user_script_slave.h"
 
 #include <map>
 
 #include "base/command_line.h"
 #include "base/logging.h"
 #include "base/perftimer.h"
 #include "base/pickle.h"
 #include "base/shared_memory.h"
 #include "base/metrics/histogram.h"
 #include "base/stringprintf.h"
 #include "chrome/common/extensions/extension.h"
 #include "chrome/common/extensions/extension_set.h"
 #include "chrome/common/url_constants.h"
 #include "chrome/renderer/chrome_render_process_observer.h"
 #include "chrome/renderer/extensions/extension_dispatcher.h"
 #include "chrome/renderer/extensions/extension_groups.h"
 #include "googleurl/src/gurl.h"
 #include "grit/renderer_resources.h"
+#include "third_party/WebKit/Source/WebKit/chromium/public/WebDataSource.h"
 #include "third_party/WebKit/Source/WebKit/chromium/public/WebDocument.h"
 #include "third_party/WebKit/Source/WebKit/chromium/public/WebFrame.h"
 #include "third_party/WebKit/Source/WebKit/chromium/public/WebSecurityOrigin.h"
 #include "third_party/WebKit/Source/WebKit/chromium/public/WebSecurityPolicy.h"
+#include "third_party/WebKit/Source/WebKit/chromium/public/WebURLRequest.h"
 #include "third_party/WebKit/Source/WebKit/chromium/public/WebVector.h"
 #include "third_party/WebKit/Source/WebKit/chromium/public/WebView.h"
 #include "ui/base/resource/resource_bundle.h"
 
 using WebKit::WebFrame;
 using WebKit::WebSecurityOrigin;
 using WebKit::WebSecurityPolicy;
 using WebKit::WebString;
 using WebKit::WebVector;
 using WebKit::WebView;
@@ skipping 191 matching lines @@
   DCHECK(sources);
   bool incognito = ChromeRenderProcessObserver::is_incognito_process();
   sources->insert(sources->begin(), WebScriptSource(WebString::fromUTF8(
       base::StringPrintf(kInitExtension,
                          extension_id.c_str(),
                          incognito ? "true" : "false"))));
 }
 
 void UserScriptSlave::InjectScripts(WebFrame* frame,
                                     UserScript::RunLocation location) {
-  GURL document_url = GURL(frame->document().url());
-  if (document_url.is_empty())
+  // Normally we would use frame->document().url() to determine the document's
+  // URL, but to decide whether to inject a content script, we use the URL from
+  // the data source. This "quirk" helps prevents content scripts from
+  // inadvertently adding DOM elements to the compose iframe in Gmail because
+  // the compose iframe's dataSource URL is about:blank, but the document URL
+  // changes to match the parent document after Gmail document.writes into
+  // it to create the editor.
+  // http://code.google.com/p/chromium/issues/detail?id=86742
+  GURL data_source_url = GURL(frame->dataSource()->request().url());
+  if (data_source_url.is_empty())
     return;
 
   if (frame->isViewSourceModeEnabled())
-    document_url = GURL(chrome::kViewSourceScheme + std::string(":") +
-                        document_url.spec());
+    data_source_url = GURL(chrome::kViewSourceScheme + std::string(":") +
+                           data_source_url.spec());
 
   PerfTimer timer;
   int num_css = 0;
   int num_scripts = 0;
 
   for (size_t i = 0; i < scripts_.size(); ++i) {
     std::vector<WebScriptSource> sources;
     UserScript* script = scripts_[i];
 
     if (frame->parent() && !script->match_all_frames())
       continue;  // Only match subframes if the script declared it wanted to.
 
     const Extension* extension = extensions_->GetByID(script->extension_id());
 
     // Since extension info is sent separately from user script info, they can
     // be out of sync. We just ignore this situation.
     if (!extension)
       continue;
 
-    if (!extension->CanExecuteScriptOnPage(document_url, script, NULL))
+    if (!extension->CanExecuteScriptOnPage(data_source_url, script, NULL))
       continue;
 
     // We rely on WebCore for CSS injection, but it's still useful to know how
     // many css files there are.
     if (location == UserScript::DOCUMENT_START)
       num_css += script->css_scripts().size();
 
     if (script->run_location() == location) {
       num_scripts += script->js_scripts().size();
       for (size_t j = 0; j < script->js_scripts().size(); ++j) {
@@ skipping 47 matching lines @@
     if (num_scripts)
       UMA_HISTOGRAM_TIMES("Extensions.InjectEnd_Time", timer.Elapsed());
   } else if (location == UserScript::DOCUMENT_IDLE) {
     UMA_HISTOGRAM_COUNTS_100("Extensions.InjectIdle_ScriptCount", num_scripts);
     if (num_scripts)
       UMA_HISTOGRAM_TIMES("Extensions.InjectIdle_Time", timer.Elapsed());
   } else {
     NOTREACHED();
   }
 }