extensions/renderer/script_injection.cc

   1 // Copyright 2014 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "extensions/renderer/script_injection.h"
   6
   7 #include <map>
   8
   9 #include "base/lazy_instance.h"
  10 #include "base/metrics/histogram.h"
  11 #include "base/timer/elapsed_timer.h"
  12 #include "base/values.h"
  13 #include "content/public/renderer/render_view.h"
  14 #include "content/public/renderer/v8_value_converter.h"
  15 #include "extensions/common/extension.h"
  16 #include "extensions/common/extension_messages.h"
  17 #include "extensions/common/feature_switch.h"
  18 #include "extensions/common/manifest_handlers/csp_info.h"
  19 #include "extensions/renderer/dom_activity_logger.h"
  20 #include "extensions/renderer/extension_groups.h"
  21 #include "extensions/renderer/extensions_renderer_client.h"
  22 #include "third_party/WebKit/public/platform/WebString.h"
  23 #include "third_party/WebKit/public/web/WebDocument.h"
  24 #include "third_party/WebKit/public/web/WebFrame.h"
  25 #include "third_party/WebKit/public/web/WebScopedUserGesture.h"
  26 #include "third_party/WebKit/public/web/WebScriptSource.h"
  27 #include "third_party/WebKit/public/web/WebSecurityOrigin.h"
  28 #include "url/gurl.h"
  29
  30 namespace extensions {
  31
  32 namespace {
  33
  34 typedef std::map<std::string, int> IsolatedWorldMap;
  35 base::LazyInstance<IsolatedWorldMap> g_isolated_worlds =
  36     LAZY_INSTANCE_INITIALIZER;
  37
  38 const int64 kInvalidRequestId = -1;
  39
  40 // The id of the next pending injection.
  41 int64 g_next_pending_id = 0;
  42
  43 bool ShouldNotifyBrowserOfInjections() {
  44   return !FeatureSwitch::scripts_require_action()->IsEnabled();
  45 }
  46
  47 // Append all the child frames of |parent_frame| to |frames_vector|.
  48 void AppendAllChildFrames(blink::WebFrame* parent_frame,
  49                           std::vector<blink::WebFrame*>* frames_vector) {
  50   DCHECK(parent_frame);
  51   for (blink::WebFrame* child_frame = parent_frame->firstChild(); child_frame;
  52        child_frame = child_frame->nextSibling()) {
  53     frames_vector->push_back(child_frame);
  54     AppendAllChildFrames(child_frame, frames_vector);
  55   }
  56 }
  57
  58 // Gets the isolated world ID to use for the given |extension| in the given
  59 // |frame|. If no isolated world has been created for that extension,
  60 // one will be created and initialized.
  61 int GetIsolatedWorldIdForExtension(const Extension* extension,
  62                                    blink::WebFrame* frame) {
  63   static int g_next_isolated_world_id =
  64       ExtensionsRendererClient::Get()->GetLowestIsolatedWorldId();
  65
  66   IsolatedWorldMap& isolated_worlds = g_isolated_worlds.Get();
  67
  68   int id = 0;
  69   IsolatedWorldMap::iterator iter = isolated_worlds.find(extension->id());
  70   if (iter != isolated_worlds.end()) {
  71     id = iter->second;
  72   } else {
  73     id = g_next_isolated_world_id++;
  74     // This map will tend to pile up over time, but realistically, you're never
  75     // going to have enough extensions for it to matter.
  76     isolated_worlds[extension->id()] = id;
  77   }
  78
  79   // We need to set the isolated world origin and CSP even if it's not a new
  80   // world since these are stored per frame, and we might not have used this
  81   // isolated world in this frame before.
  82   frame->setIsolatedWorldSecurityOrigin(
  83       id, blink::WebSecurityOrigin::create(extension->url()));
  84   frame->setIsolatedWorldContentSecurityPolicy(
  85       id,
  86       blink::WebString::fromUTF8(CSPInfo::GetContentSecurityPolicy(extension)));
  87
  88   return id;
  89 }
  90
  91 }  // namespace
  92
  93 // static
  94 std::string ScriptInjection::GetExtensionIdForIsolatedWorld(
  95     int isolated_world_id) {
  96   IsolatedWorldMap& isolated_worlds = g_isolated_worlds.Get();
  97
  98   for (IsolatedWorldMap::iterator iter = isolated_worlds.begin();
  99        iter != isolated_worlds.end();
 100        ++iter) {
 101     if (iter->second == isolated_world_id)
 102       return iter->first;
 103   }
 104   return std::string();
 105 }
 106
 107 // static
 108 void ScriptInjection::RemoveIsolatedWorld(const std::string& extension_id) {
 109   g_isolated_worlds.Get().erase(extension_id);
 110 }
 111
 112 ScriptInjection::ScriptInjection(
 113     scoped_ptr<ScriptInjector> injector,
 114     blink::WebFrame* web_frame,
 115     const std::string& extension_id,
 116     UserScript::RunLocation run_location,
 117     int tab_id)
 118     : injector_(injector.Pass()),
 119       web_frame_(web_frame),
 120       extension_id_(extension_id),
 121       run_location_(run_location),
 122       tab_id_(tab_id),
 123       request_id_(kInvalidRequestId),
 124       complete_(false) {
 125 }
 126
 127 ScriptInjection::~ScriptInjection() {
 128   if (!complete_)
 129     injector_->OnWillNotInject(ScriptInjector::WONT_INJECT);
 130 }
 131
 132 bool ScriptInjection::TryToInject(UserScript::RunLocation current_location,
 133                                   const Extension* extension,
 134                                   ScriptsRunInfo* scripts_run_info) {
 135   if (current_location < run_location_)
 136     return false;  // Wait for the right location.
 137
 138   if (request_id_ != kInvalidRequestId)
 139     return false;  // We're waiting for permission right now, try again later.
 140
 141   if (!extension) {
 142     NotifyWillNotInject(ScriptInjector::EXTENSION_REMOVED);
 143     return true;  // We're done.
 144   }
 145
 146   switch (injector_->CanExecuteOnFrame(
 147       extension, web_frame_, tab_id_, web_frame_->top()->document().url())) {
 148     case PermissionsData::ACCESS_DENIED:
 149       NotifyWillNotInject(ScriptInjector::NOT_ALLOWED);
 150       return true;  // We're done.
 151     case PermissionsData::ACCESS_WITHHELD:
 152       RequestPermission();
 153       return false;  // Wait around for permission.
 154     case PermissionsData::ACCESS_ALLOWED:
 155       Inject(extension, scripts_run_info);
 156       return true;  // We're done!
 157   }
 158
 159   // Some compilers don't realize that we always return from the switch() above.
 160   // Make them happy.
 161   return false;
 162 }
 163
 164 bool ScriptInjection::OnPermissionGranted(const Extension* extension,
 165                                           ScriptsRunInfo* scripts_run_info) {
 166   if (!extension) {
 167     NotifyWillNotInject(ScriptInjector::EXTENSION_REMOVED);
 168     return false;
 169   }
 170
 171   Inject(extension, scripts_run_info);
 172   return true;
 173 }
 174
 175 void ScriptInjection::RequestPermission() {
 176   content::RenderView* render_view =
 177       content::RenderView::FromWebView(web_frame()->top()->view());
 178
 179   // If we are just notifying the browser of the injection, then send an
 180   // invalid request (which is treated like a notification).
 181   request_id_ = ShouldNotifyBrowserOfInjections() ? kInvalidRequestId
 182                                                   : g_next_pending_id++;
 183   render_view->Send(new ExtensionHostMsg_RequestScriptInjectionPermission(
 184       render_view->GetRoutingID(),
 185       extension_id_,
 186       injector_->script_type(),
 187       request_id_));
 188 }
 189
 190 void ScriptInjection::NotifyWillNotInject(
 191     ScriptInjector::InjectFailureReason reason) {
 192   complete_ = true;
 193   injector_->OnWillNotInject(reason);
 194 }
 195
 196 void ScriptInjection::Inject(const Extension* extension,
 197                              ScriptsRunInfo* scripts_run_info) {
 198   DCHECK(extension);
 199   DCHECK(scripts_run_info);
 200   DCHECK(!complete_);
 201
 202   if (ShouldNotifyBrowserOfInjections())
 203     RequestPermission();
 204
 205   std::vector<blink::WebFrame*> frame_vector;
 206   frame_vector.push_back(web_frame_);
 207   if (injector_->ShouldExecuteInChildFrames())
 208     AppendAllChildFrames(web_frame_, &frame_vector);
 209
 210   scoped_ptr<blink::WebScopedUserGesture> gesture;
 211   if (injector_->IsUserGesture())
 212     gesture.reset(new blink::WebScopedUserGesture());
 213
 214   bool inject_js = injector_->ShouldInjectJs(run_location_);
 215   bool inject_css = injector_->ShouldInjectCss(run_location_);
 216   DCHECK(inject_js || inject_css);
 217
 218   scoped_ptr<base::ListValue> execution_results(new base::ListValue());
 219   GURL top_url = web_frame_->top()->document().url();
 220   for (std::vector<blink::WebFrame*>::iterator iter = frame_vector.begin();
 221        iter != frame_vector.end();
 222        ++iter) {
 223     blink::WebFrame* frame = *iter;
 224
 225     // We recheck access here in the renderer for extra safety against races
 226     // with navigation, but different frames can have different URLs, and the
 227     // extension might only have access to a subset of them.
 228     // For child frames, we just skip ones the extension doesn't have access
 229     // to and carry on.
 230     // Note: we don't consider ACCESS_WITHHELD because there is nowhere to
 231     // surface a request for a child frame.
 232     // TODO(rdevlin.cronin): We should ask for permission somehow.
 233     if (injector_->CanExecuteOnFrame(extension, frame, tab_id_, top_url) ==
 234         PermissionsData::ACCESS_DENIED) {
 235       DCHECK(frame->parent());
 236       continue;
 237     }
 238     if (inject_js)
 239       InjectJs(extension, frame, execution_results.get());
 240     if (inject_css)
 241       InjectCss(frame);
 242   }
 243
 244   complete_ = true;
 245   injector_->OnInjectionComplete(execution_results.Pass(),
 246                                  scripts_run_info,
 247                                  run_location_);
 248 }
 249
 250 void ScriptInjection::InjectJs(const Extension* extension,
 251                                blink::WebFrame* frame,
 252                                base::ListValue* execution_results) {
 253   std::vector<blink::WebScriptSource> sources =
 254       injector_->GetJsSources(run_location_);
 255   bool in_main_world = injector_->ShouldExecuteInMainWorld();
 256   int world_id = in_main_world
 257                      ? DOMActivityLogger::kMainWorldId
 258                      : GetIsolatedWorldIdForExtension(extension, frame);
 259   bool expects_results = injector_->ExpectsResults();
 260
 261   base::ElapsedTimer exec_timer;
 262   DOMActivityLogger::AttachToWorld(world_id, extension->id());
 263   v8::HandleScope scope(v8::Isolate::GetCurrent());
 264   v8::Local<v8::Value> script_value;
 265   if (in_main_world) {
 266     // We only inject in the main world for javascript: urls.
 267     DCHECK_EQ(1u, sources.size());
 268
 269     const blink::WebScriptSource& source = sources.front();
 270     if (expects_results)
 271       script_value = frame->executeScriptAndReturnValue(source);
 272     else
 273       frame->executeScript(source);
 274   } else {  // in isolated world
 275     scoped_ptr<blink::WebVector<v8::Local<v8::Value> > > results;
 276     if (expects_results)
 277       results.reset(new blink::WebVector<v8::Local<v8::Value> >());
 278     frame->executeScriptInIsolatedWorld(world_id,
 279                                         &sources.front(),
 280                                         sources.size(),
 281                                         EXTENSION_GROUP_CONTENT_SCRIPTS,
 282                                         results.get());
 283     if (expects_results && !results->isEmpty())
 284       script_value = (*results)[0];
 285   }
 286
 287   UMA_HISTOGRAM_TIMES("Extensions.InjectScriptTime", exec_timer.Elapsed());
 288
 289   if (expects_results) {
 290     // Right now, we only support returning single results (per frame).
 291     scoped_ptr<content::V8ValueConverter> v8_converter(
 292         content::V8ValueConverter::create());
 293     // It's safe to always use the main world context when converting
 294     // here. V8ValueConverterImpl shouldn't actually care about the
 295     // context scope, and it switches to v8::Object's creation context
 296     // when encountered.
 297     v8::Local<v8::Context> context = frame->mainWorldScriptContext();
 298     scoped_ptr<base::Value> result(
 299         v8_converter->FromV8Value(script_value, context));
 300     // Always append an execution result (i.e. no result == null result)
 301     // so that |execution_results| lines up with the frames.
 302     execution_results->Append(result.get() ? result.release()
 303                                            : base::Value::CreateNullValue());
 304   }
 305 }
 306
 307 void ScriptInjection::InjectCss(blink::WebFrame* frame) {
 308   std::vector<std::string> css_sources =
 309       injector_->GetCssSources(run_location_);
 310   for (std::vector<std::string>::const_iterator iter = css_sources.begin();
 311        iter != css_sources.end();
 312        ++iter) {
 313     frame->document().insertStyleSheet(blink::WebString::fromUTF8(*iter));
 314   }
 315 }
 316
 317 }  // namespace extensions