extensions/renderer/script_context.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_context.h"
   6
   7 #include "base/logging.h"
   8 #include "base/memory/scoped_ptr.h"
   9 #include "base/strings/string_split.h"
  10 #include "base/strings/string_util.h"
  11 #include "base/strings/stringprintf.h"
  12 #include "base/values.h"
  13 #include "content/public/child/v8_value_converter.h"
  14 #include "content/public/common/url_constants.h"
  15 #include "content/public/renderer/render_frame.h"
  16 #include "extensions/common/constants.h"
  17 #include "extensions/common/extension.h"
  18 #include "extensions/common/extension_api.h"
  19 #include "extensions/common/extension_set.h"
  20 #include "extensions/common/extension_urls.h"
  21 #include "extensions/common/features/base_feature_provider.h"
  22 #include "extensions/common/manifest_handlers/sandboxed_page_info.h"
  23 #include "extensions/common/permissions/permissions_data.h"
  24 #include "gin/per_context_data.h"
  25 #include "third_party/WebKit/public/web/WebDataSource.h"
  26 #include "third_party/WebKit/public/web/WebDocument.h"
  27 #include "third_party/WebKit/public/web/WebFrame.h"
  28 #include "third_party/WebKit/public/web/WebLocalFrame.h"
  29 #include "third_party/WebKit/public/web/WebScopedMicrotaskSuppression.h"
  30 #include "third_party/WebKit/public/web/WebSecurityOrigin.h"
  31 #include "third_party/WebKit/public/web/WebView.h"
  32 #include "v8/include/v8.h"
  33
  34 using content::V8ValueConverter;
  35
  36 namespace extensions {
  37
  38 namespace {
  39
  40 std::string GetContextTypeDescriptionString(Feature::Context context_type) {
  41   switch (context_type) {
  42     case Feature::UNSPECIFIED_CONTEXT:
  43       return "UNSPECIFIED";
  44     case Feature::BLESSED_EXTENSION_CONTEXT:
  45       return "BLESSED_EXTENSION";
  46     case Feature::UNBLESSED_EXTENSION_CONTEXT:
  47       return "UNBLESSED_EXTENSION";
  48     case Feature::CONTENT_SCRIPT_CONTEXT:
  49       return "CONTENT_SCRIPT";
  50     case Feature::WEB_PAGE_CONTEXT:
  51       return "WEB_PAGE";
  52     case Feature::BLESSED_WEB_PAGE_CONTEXT:
  53       return "BLESSED_WEB_PAGE";
  54     case Feature::WEBUI_CONTEXT:
  55       return "WEBUI";
  56   }
  57   NOTREACHED();
  58   return std::string();
  59 }
  60
  61 }  // namespace
  62
  63 // A gin::Runner that delegates to its ScriptContext.
  64 class ScriptContext::Runner : public gin::Runner {
  65  public:
  66   explicit Runner(ScriptContext* context);
  67
  68   // gin::Runner overrides.
  69   void Run(const std::string& source,
  70            const std::string& resource_name) override;
  71   v8::Local<v8::Value> Call(v8::Local<v8::Function> function,
  72                             v8::Local<v8::Value> receiver,
  73                             int argc,
  74                             v8::Local<v8::Value> argv[]) override;
  75   gin::ContextHolder* GetContextHolder() override;
  76
  77  private:
  78   ScriptContext* context_;
  79 };
  80
  81 ScriptContext::ScriptContext(const v8::Local<v8::Context>& v8_context,
  82                              blink::WebLocalFrame* web_frame,
  83                              const Extension* extension,
  84                              Feature::Context context_type,
  85                              const Extension* effective_extension,
  86                              Feature::Context effective_context_type)
  87     : is_valid_(true),
  88       v8_context_(v8_context->GetIsolate(), v8_context),
  89       web_frame_(web_frame),
  90       extension_(extension),
  91       context_type_(context_type),
  92       effective_extension_(effective_extension),
  93       effective_context_type_(effective_context_type),
  94       safe_builtins_(this),
  95       isolate_(v8_context->GetIsolate()),
  96       url_(web_frame_ ? GetDataSourceURLForFrame(web_frame_) : GURL()),
  97       runner_(new Runner(this)) {
  98   VLOG(1) << "Created context:\n" << GetDebugString();
  99   gin::PerContextData* gin_data = gin::PerContextData::From(v8_context);
 100   CHECK(gin_data);  // may fail if the v8::Context hasn't been registered yet
 101   gin_data->set_runner(runner_.get());
 102 }
 103
 104 ScriptContext::~ScriptContext() {
 105   VLOG(1) << "Destroyed context for extension\n"
 106           << "  extension id: " << GetExtensionID() << "\n"
 107           << "  effective extension id: "
 108           << (effective_extension_.get() ? effective_extension_->id() : "");
 109   CHECK(!is_valid_) << "ScriptContexts must be invalidated before destruction";
 110 }
 111
 112 // static
 113 bool ScriptContext::IsSandboxedPage(const ExtensionSet& extensions,
 114                                     const GURL& url) {
 115   // TODO(kalman): This is checking the wrong thing. See comment in
 116   // HasAccessOrThrowError.
 117   if (url.SchemeIs(kExtensionScheme)) {
 118     const Extension* extension = extensions.GetByID(url.host());
 119     if (extension) {
 120       return SandboxedPageInfo::IsSandboxedPage(extension, url.path());
 121     }
 122   }
 123   return false;
 124 }
 125
 126 void ScriptContext::Invalidate() {
 127   CHECK(is_valid_);
 128   is_valid_ = false;
 129
 130   // TODO(kalman): Make ModuleSystem use AddInvalidationObserver.
 131   // Ownership graph is a bit weird here.
 132   if (module_system_)
 133     module_system_->Invalidate();
 134
 135   // Swap |invalidate_observers_| to a local variable to clear it, and to make
 136   // sure it's not mutated as we iterate.
 137   std::vector<base::Closure> observers;
 138   observers.swap(invalidate_observers_);
 139   for (const base::Closure& observer : observers) {
 140     observer.Run();
 141   }
 142   DCHECK(invalidate_observers_.empty())
 143       << "Invalidation observers cannot be added during invalidation";
 144
 145   runner_.reset();
 146   v8_context_.Reset();
 147 }
 148
 149 void ScriptContext::AddInvalidationObserver(const base::Closure& observer) {
 150   invalidate_observers_.push_back(observer);
 151 }
 152
 153 const std::string& ScriptContext::GetExtensionID() const {
 154   return extension_.get() ? extension_->id() : base::EmptyString();
 155 }
 156
 157 content::RenderFrame* ScriptContext::GetRenderFrame() const {
 158   if (web_frame_)
 159     return content::RenderFrame::FromWebFrame(web_frame_);
 160   return NULL;
 161 }
 162
 163 v8::Local<v8::Value> ScriptContext::CallFunction(
 164     const v8::Local<v8::Function>& function,
 165     int argc,
 166     v8::Local<v8::Value> argv[]) const {
 167   v8::EscapableHandleScope handle_scope(isolate());
 168   v8::Context::Scope scope(v8_context());
 169
 170   blink::WebScopedMicrotaskSuppression suppression;
 171   if (!is_valid_) {
 172     return handle_scope.Escape(
 173         v8::Local<v8::Primitive>(v8::Undefined(isolate())));
 174   }
 175
 176   v8::Local<v8::Object> global = v8_context()->Global();
 177   if (!web_frame_)
 178     return handle_scope.Escape(function->Call(global, argc, argv));
 179   return handle_scope.Escape(
 180       v8::Local<v8::Value>(web_frame_->callFunctionEvenIfScriptDisabled(
 181           function, global, argc, argv)));
 182 }
 183
 184 v8::Local<v8::Value> ScriptContext::CallFunction(
 185     const v8::Local<v8::Function>& function) const {
 186   return CallFunction(function, 0, nullptr);
 187 }
 188
 189 Feature::Availability ScriptContext::GetAvailability(
 190     const std::string& api_name) {
 191   // Hack: Hosted apps should have the availability of messaging APIs based on
 192   // the URL of the page (which might have access depending on some extension
 193   // with externally_connectable), not whether the app has access to messaging
 194   // (which it won't).
 195   const Extension* extension = extension_.get();
 196   if (extension && extension->is_hosted_app() &&
 197       (api_name == "runtime.connect" || api_name == "runtime.sendMessage")) {
 198     extension = NULL;
 199   }
 200   return ExtensionAPI::GetSharedInstance()->IsAvailable(
 201       api_name, extension, context_type_, GetURL());
 202 }
 203
 204 void ScriptContext::DispatchEvent(const char* event_name,
 205                                   v8::Local<v8::Array> args) const {
 206   v8::HandleScope handle_scope(isolate());
 207   v8::Context::Scope context_scope(v8_context());
 208
 209   v8::Local<v8::Value> argv[] = {v8::String::NewFromUtf8(isolate(), event_name),
 210                                  args};
 211   module_system_->CallModuleMethod(
 212       kEventBindings, "dispatchEvent", arraysize(argv), argv);
 213 }
 214
 215 void ScriptContext::DispatchOnUnloadEvent() {
 216   v8::HandleScope handle_scope(isolate());
 217   v8::Context::Scope context_scope(v8_context());
 218   module_system_->CallModuleMethod("unload_event", "dispatch");
 219 }
 220
 221 std::string ScriptContext::GetContextTypeDescription() const {
 222   return GetContextTypeDescriptionString(context_type_);
 223 }
 224
 225 std::string ScriptContext::GetEffectiveContextTypeDescription() const {
 226   return GetContextTypeDescriptionString(effective_context_type_);
 227 }
 228
 229 GURL ScriptContext::GetURL() const {
 230   return url_;
 231 }
 232
 233 bool ScriptContext::IsAnyFeatureAvailableToContext(const Feature& api) {
 234   return ExtensionAPI::GetSharedInstance()->IsAnyFeatureAvailableToContext(
 235       api, extension(), context_type(), GetDataSourceURLForFrame(web_frame()));
 236 }
 237
 238 // static
 239 GURL ScriptContext::GetDataSourceURLForFrame(const blink::WebFrame* frame) {
 240   // Normally we would use frame->document().url() to determine the document's
 241   // URL, but to decide whether to inject a content script, we use the URL from
 242   // the data source. This "quirk" helps prevents content scripts from
 243   // inadvertently adding DOM elements to the compose iframe in Gmail because
 244   // the compose iframe's dataSource URL is about:blank, but the document URL
 245   // changes to match the parent document after Gmail document.writes into
 246   // it to create the editor.
 247   // http://code.google.com/p/chromium/issues/detail?id=86742
 248   blink::WebDataSource* data_source = frame->provisionalDataSource()
 249                                           ? frame->provisionalDataSource()
 250                                           : frame->dataSource();
 251   return data_source ? GURL(data_source->request().url()) : GURL();
 252 }
 253
 254 // static
 255 GURL ScriptContext::GetEffectiveDocumentURL(const blink::WebFrame* frame,
 256                                             const GURL& document_url,
 257                                             bool match_about_blank) {
 258   // Common scenario. If |match_about_blank| is false (as is the case in most
 259   // extensions), or if the frame is not an about:-page, just return
 260   // |document_url| (supposedly the URL of the frame).
 261   if (!match_about_blank || !document_url.SchemeIs(url::kAboutScheme))
 262     return document_url;
 263
 264   // Non-sandboxed about:blank and about:srcdoc pages inherit their security
 265   // origin from their parent frame/window. So, traverse the frame/window
 266   // hierarchy to find the closest non-about:-page and return its URL.
 267   const blink::WebFrame* parent = frame;
 268   do {
 269     parent = parent->parent() ? parent->parent() : parent->opener();
 270   } while (parent != NULL && !parent->document().isNull() &&
 271            GURL(parent->document().url()).SchemeIs(url::kAboutScheme));
 272
 273   if (parent && !parent->document().isNull()) {
 274     // Only return the parent URL if the frame can access it.
 275     const blink::WebDocument& parent_document = parent->document();
 276     if (frame->document().securityOrigin().canAccess(
 277             parent_document.securityOrigin()))
 278       return parent_document.url();
 279   }
 280   return document_url;
 281 }
 282
 283 ScriptContext* ScriptContext::GetContext() { return this; }
 284
 285 void ScriptContext::OnResponseReceived(const std::string& name,
 286                                        int request_id,
 287                                        bool success,
 288                                        const base::ListValue& response,
 289                                        const std::string& error) {
 290   v8::HandleScope handle_scope(isolate());
 291
 292   scoped_ptr<V8ValueConverter> converter(V8ValueConverter::create());
 293   v8::Local<v8::Value> argv[] = {
 294       v8::Integer::New(isolate(), request_id),
 295       v8::String::NewFromUtf8(isolate(), name.c_str()),
 296       v8::Boolean::New(isolate(), success),
 297       converter->ToV8Value(&response,
 298                            v8::Local<v8::Context>::New(isolate(), v8_context_)),
 299       v8::String::NewFromUtf8(isolate(), error.c_str())};
 300
 301   v8::Local<v8::Value> retval = module_system()->CallModuleMethod(
 302       "sendRequest", "handleResponse", arraysize(argv), argv);
 303
 304   // In debug, the js will validate the callback parameters and return a
 305   // string if a validation error has occured.
 306   DCHECK(retval.IsEmpty() || retval->IsUndefined())
 307       << *v8::String::Utf8Value(retval);
 308 }
 309
 310 void ScriptContext::SetContentCapabilities(
 311     const APIPermissionSet& permissions) {
 312   content_capabilities_ = permissions;
 313 }
 314
 315 bool ScriptContext::HasAPIPermission(APIPermission::ID permission) const {
 316   if (effective_extension_.get()) {
 317     return effective_extension_->permissions_data()->HasAPIPermission(
 318         permission);
 319   } else if (context_type() == Feature::WEB_PAGE_CONTEXT) {
 320     // Only web page contexts may be granted content capabilities. Other
 321     // contexts are either privileged WebUI or extensions with their own set of
 322     // permissions.
 323     if (content_capabilities_.find(permission) != content_capabilities_.end())
 324       return true;
 325   }
 326   return false;
 327 }
 328
 329 bool ScriptContext::HasAccessOrThrowError(const std::string& name) {
 330   // Theoretically[1] we could end up with bindings being injected into
 331   // sandboxed frames, for example content scripts. Don't let them execute API
 332   // functions.
 333   //
 334   // In any case, this check is silly. The frame's document's security origin
 335   // already tells us if it's sandboxed. The only problem is that until
 336   // crbug.com/466373 is fixed, we don't know the security origin up-front and
 337   // may not know it here, either.
 338   //
 339   // [1] citation needed. This ScriptContext should already be in a state that
 340   // doesn't allow this, from ScriptContextSet::ClassifyJavaScriptContext.
 341   if (extension() &&
 342       SandboxedPageInfo::IsSandboxedPage(extension(), url_.path())) {
 343     static const char kMessage[] =
 344         "%s cannot be used within a sandboxed frame.";
 345     std::string error_msg = base::StringPrintf(kMessage, name.c_str());
 346     isolate()->ThrowException(v8::Exception::Error(
 347         v8::String::NewFromUtf8(isolate(), error_msg.c_str())));
 348     return false;
 349   }
 350
 351   Feature::Availability availability = GetAvailability(name);
 352   if (!availability.is_available()) {
 353     isolate()->ThrowException(v8::Exception::Error(
 354         v8::String::NewFromUtf8(isolate(), availability.message().c_str())));
 355     return false;
 356   }
 357
 358   return true;
 359 }
 360
 361 std::string ScriptContext::GetDebugString() const {
 362   return base::StringPrintf(
 363       "  extension id:           %s\n"
 364       "  frame:                  %p\n"
 365       "  URL:                    %s\n"
 366       "  context_type:           %s\n"
 367       "  effective extension id: %s\n"
 368       "  effective context type: %s",
 369       extension_.get() ? extension_->id().c_str() : "(none)", web_frame_,
 370       GetURL().spec().c_str(), GetContextTypeDescription().c_str(),
 371       effective_extension_.get() ? effective_extension_->id().c_str()
 372                                  : "(none)",
 373       GetEffectiveContextTypeDescription().c_str());
 374 }
 375
 376 ScriptContext::Runner::Runner(ScriptContext* context) : context_(context) {
 377 }
 378
 379 void ScriptContext::Runner::Run(const std::string& source,
 380                                 const std::string& resource_name) {
 381   context_->module_system()->RunString(source, resource_name);
 382 }
 383
 384 v8::Local<v8::Value> ScriptContext::Runner::Call(
 385     v8::Local<v8::Function> function,
 386     v8::Local<v8::Value> receiver,
 387     int argc,
 388     v8::Local<v8::Value> argv[]) {
 389   return context_->CallFunction(function, argc, argv);
 390 }
 391
 392 gin::ContextHolder* ScriptContext::Runner::GetContextHolder() {
 393   v8::HandleScope handle_scope(context_->isolate());
 394   return gin::PerContextData::From(context_->v8_context())->context_holder();
 395 }
 396
 397 }  // namespace extensions