Move the new Help App untrusted context to untrusted scheme.

Previously we served the sandboxed iframe at
chrome://help-app-guest. Now the untrusted scheme is ready, using
chrome-untrusted://help-app.

Bug: b/149713277
Change-Id: If474995c39dbcce85d868535fa33effd9592d5c7
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2066373Reviewed-by: Giovanni Ortuño Urquidi <ortuno@chromium.org>
Reviewed-by: Kinuko Yasuda <kinuko@chromium.org>
Reviewed-by: Trent Apted <tapted@chromium.org>
Commit-Queue: Rachel Carpenter <carpenterr@google.com>
Cr-Commit-Position: refs/heads/master@{#744077}

chromeos/components/help_app_ui/BUILD.gn

@@ -10,13 +10,13 @@ assert(is_chromeos, "Help App is Chrome OS only")
 
 static_library("help_app_ui") {
   sources = [
-    "help_app_guest_ui.cc",
-    "help_app_guest_ui.h",
     "help_app_page_handler.cc",
     "help_app_page_handler.h",
     "help_app_ui.cc",
     "help_app_ui.h",
     "help_app_ui_delegate.h",
+    "help_app_untrusted_ui.cc",
+    "help_app_untrusted_ui.h",
     "url_constants.cc",
     "url_constants.h",
   ]
@@ -29,6 +29,7 @@ static_library("help_app_ui") {
     "//chromeos/resources:help_app_resources",
     "//chromeos/system",
     "//content/public/browser",
+    "//content/public/common",
     "//mojo/public/cpp/bindings",
     "//mojo/public/cpp/platform",
     "//ui/resources:webui_resources_grd_grit",

chromeos/components/help_app_ui/DEPS

@@ -2,6 +2,7 @@ include_rules = [
   # Do not add chrome here (use a delegate instead).
   "+chromeos/grit/chromeos_help_app_resources.h",
   "+content/public/browser",
+  "+content/public/common",
   "+ui/resources/grit/webui_resources.h",
   "+ui/webui",
 ]

chromeos/components/help_app_ui/help_app_ui.cc

@@ -6,13 +6,14 @@
 
 #include <utility>
 
-#include "chromeos/components/help_app_ui/help_app_guest_ui.h"
 #include "chromeos/components/help_app_ui/help_app_page_handler.h"
+#include "chromeos/components/help_app_ui/help_app_untrusted_ui.h"
 #include "chromeos/components/help_app_ui/url_constants.h"
 #include "chromeos/grit/chromeos_help_app_resources.h"
 #include "content/public/browser/web_contents.h"
 #include "content/public/browser/web_ui.h"
 #include "content/public/browser/web_ui_data_source.h"
+#include "content/public/common/url_constants.h"
 
 namespace chromeos {
 
@@ -41,12 +42,17 @@ HelpAppUI::HelpAppUI(content::WebUI* web_ui,
       web_ui->GetWebContents()->GetBrowserContext();
   content::WebUIDataSource* host_source = CreateHostDataSource();
   content::WebUIDataSource::Add(browser_context, host_source);
-  // We need a CSP override to use the guest origin in the host.
-  std::string csp = std::string("frame-src ") + kChromeUIHelpAppGuestURL + ";";
+  // We need a CSP override to use the chrome-untrusted:// scheme in the host.
+  std::string csp =
+      std::string("frame-src ") + kChromeUIHelpAppUntrustedURL + ";";
   host_source->OverrideContentSecurityPolicyChildSrc(csp);
 
-  content::WebUIDataSource* guest_source = CreateHelpAppGuestDataSource();
-  content::WebUIDataSource::Add(browser_context, guest_source);
+  content::WebUIDataSource* untrusted_source =
+      CreateHelpAppUntrustedDataSource();
+  content::WebUIDataSource::Add(browser_context, untrusted_source);
+
+  // Add ability to request chrome-untrusted: URLs.
+  web_ui->AddRequestableScheme(content::kChromeUIUntrustedScheme);
 }
 
 HelpAppUI::~HelpAppUI() = default;

chromeos/components/help_app_ui/help_app_guest_ui.cc → chromeos/components/help_app_ui/help_app_untrusted_ui.cc

@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#include "chromeos/components/help_app_ui/help_app_guest_ui.h"
+#include "chromeos/components/help_app_ui/help_app_untrusted_ui.h"
 
 #include "base/system/sys_info.h"
 #include "chromeos/components/help_app_ui/url_constants.h"
@@ -16,9 +16,9 @@
 namespace chromeos {
 
 // static
-content::WebUIDataSource* CreateHelpAppGuestDataSource() {
+content::WebUIDataSource* CreateHelpAppUntrustedDataSource() {
   content::WebUIDataSource* source =
-      content::WebUIDataSource::Create(kChromeUIHelpAppGuestHost);
+      content::WebUIDataSource::Create(kChromeUIHelpAppUntrustedURL);
   source->AddResourcePath("app.html", IDR_HELP_APP_APP_HTML);
   source->AddResourcePath("app_bin.js", IDR_HELP_APP_APP_BIN_JS);
   source->AddResourcePath("load_time_data.js", IDR_WEBUI_JS_LOAD_TIME_DATA);
@@ -40,8 +40,7 @@ content::WebUIDataSource* CreateHelpAppGuestDataSource() {
   source->AddString("customizationId", customization_id);
   source->UseStringsJs();
 
-  // TODO(crbug.com/1023700): Better solution before launch.
-  source->DisableDenyXFrameOptions();
+  source->AddFrameAncestor(GURL(kChromeUIHelpAppURL));
   return source;
 }
 

chromeos/components/help_app_ui/help_app_guest_ui.h → chromeos/components/help_app_ui/help_app_untrusted_ui.h

-// Copyright 2019 The Chromium Authors. All rights reserved.
+// Copyright 2020 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.
 
-#ifndef CHROMEOS_COMPONENTS_HELP_APP_UI_HELP_APP_GUEST_UI_H_
-#define CHROMEOS_COMPONENTS_HELP_APP_UI_HELP_APP_GUEST_UI_H_
+#ifndef CHROMEOS_COMPONENTS_HELP_APP_UI_HELP_APP_UNTRUSTED_UI_H_
+#define CHROMEOS_COMPONENTS_HELP_APP_UI_HELP_APP_UNTRUSTED_UI_H_
 
 namespace content {
 class WebUIDataSource;
 }
 
 namespace chromeos {
-// The data source creation for chrome://help-app-guest.
-content::WebUIDataSource* CreateHelpAppGuestDataSource();
+// The data source creation for chrome-untrusted://help-app.
+content::WebUIDataSource* CreateHelpAppUntrustedDataSource();
 }  // namespace chromeos
 
-#endif  // CHROMEOS_COMPONENTS_HELP_APP_UI_HELP_APP_GUEST_UI_H_
+#endif  // CHROMEOS_COMPONENTS_HELP_APP_UI_HELP_APP_UNTRUSTED_UI_H_

chromeos/components/help_app_ui/resources/index.html

@@ -23,4 +23,4 @@
 <script src="chrome://resources/mojo/mojo/public/js/mojo_bindings_lite.js"></script>
 <script src="/help_app.mojom-lite.js"></script>
 <script src="/browser_proxy.js"></script>
-<iframe src="chrome://help-app-guest/app.html"></iframe>
+<iframe src="chrome-untrusted://help-app/app.html"></iframe>

chromeos/components/help_app_ui/test/help_app_ui_browsertest.js

@@ -9,7 +9,7 @@
 GEN('#include "chromeos/constants/chromeos_features.h"');
 
 const HOST_ORIGIN = 'chrome://help-app';
-const GUEST_ORIGIN = 'chrome://help-app-guest';
+const GUEST_ORIGIN = 'chrome-untrusted://help-app';
 
 var HelpAppUIBrowserTest = class extends testing.Test {
   /** @override */

chromeos/components/help_app_ui/url_constants.cc

@@ -8,7 +8,6 @@ namespace chromeos {
 
 const char kChromeUIHelpAppHost[] = "help-app";
 const char kChromeUIHelpAppURL[] = "chrome://help-app/";
-const char kChromeUIHelpAppGuestHost[] = "help-app-guest";
-const char kChromeUIHelpAppGuestURL[] = "chrome://help-app-guest/";
+const char kChromeUIHelpAppUntrustedURL[] = "chrome-untrusted://help-app/";
 
 }  // namespace chromeos

chromeos/components/help_app_ui/url_constants.h

@@ -9,8 +9,7 @@ namespace chromeos {
 
 extern const char kChromeUIHelpAppHost[];
 extern const char kChromeUIHelpAppURL[];
-extern const char kChromeUIHelpAppGuestHost[];
-extern const char kChromeUIHelpAppGuestURL[];
+extern const char kChromeUIHelpAppUntrustedURL[];
 
 }  // namespace chromeos