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 "content/public/renderer/render_view.h"
  17 #include "extensions/common/constants.h"
  18 #include "extensions/common/extension.h"
  19 #include "extensions/common/extension_api.h"
  20 #include "extensions/common/extension_set.h"
  21 #include "extensions/common/extension_urls.h"
  22 #include "extensions/common/features/base_feature_provider.h"
  23 #include "extensions/common/manifest_handlers/sandboxed_page_info.h"
  24 #include "extensions/common/permissions/permissions_data.h"
  25 #include "gin/per_context_data.h"
  26 #include "third_party/WebKit/public/web/WebDataSource.h"
  27 #include "third_party/WebKit/public/web/WebDocument.h"
  28 #include "third_party/WebKit/public/web/WebFrame.h"
  29 #include "third_party/WebKit/public/web/WebLocalFrame.h"
  30 #include "third_party/WebKit/public/web/WebScopedMicrotaskSuppression.h"
  31 #include "third_party/WebKit/public/web/WebSecurityOrigin.h"
  32 #include "third_party/WebKit/public/web/WebView.h"
  33 #include "v8/include/v8.h"
  34
  35 using content::V8ValueConverter;
  36
  37 namespace extensions {
  38
  39 namespace {
  40
  41 std::string GetContextTypeDescriptionString(Feature::Context context_type) {
  42   switch (context_type) {
  43     case Feature::UNSPECIFIED_CONTEXT:
  44       return "UNSPECIFIED";
  45     case Feature::BLESSED_EXTENSION_CONTEXT:
  46       return "BLESSED_EXTENSION";
  47     case Feature::UNBLESSED_EXTENSION_CONTEXT:
  48       return "UNBLESSED_EXTENSION";
  49     case Feature::CONTENT_SCRIPT_CONTEXT:
  50       return "CONTENT_SCRIPT";
  51     case Feature::WEB_PAGE_CONTEXT:
  52       return "WEB_PAGE";
  53     case Feature::BLESSED_WEB_PAGE_CONTEXT:
  54       return "BLESSED_WEB_PAGE";
  55     case Feature::WEBUI_CONTEXT:
  56       return "WEBUI";
  57   }
  58   NOTREACHED();
  59   return std::string();
  60 }
  61
  62 }  // namespace
  63
  64 // A gin::Runner that delegates to its ScriptContext.
  65 class ScriptContext::Runner : public gin::Runner {
  66  public:
  67   explicit Runner(ScriptContext* context);
  68
  69   // gin::Runner overrides.
  70   void Run(const std::string& source,
  71            const std::string& resource_name) override;
  72   v8::Local<v8::Value> Call(v8::Local<v8::Function> function,
  73                             v8::Local<v8::Value> receiver,
  74                             int argc,
  75                             v8::Local<v8::Value> argv[]) override;
  76   gin::ContextHolder* GetContextHolder() override;
  77
  78  private:
  79   ScriptContext* context_;
  80 };
  81
  82 ScriptContext::ScriptContext(const v8::Local<v8::Context>& v8_context,
  83                              blink::WebLocalFrame* web_frame,
  84                              const Extension* extension,
  85                              Feature::Context context_type,
  86                              const Extension* effective_extension,
  87                              Feature::Context effective_context_type)
  88     : is_valid_(true),
  89       v8_context_(v8_context->GetIsolate(), v8_context),
  90       web_frame_(web_frame),
  91       extension_(extension),
  92       context_type_(context_type),
  93       effective_extension_(effective_extension),
  94       effective_context_type_(effective_context_type),
  95       safe_builtins_(this),
  96       isolate_(v8_context->GetIsolate()),
  97       url_(web_frame_ ? GetDataSourceURLForFrame(web_frame_) : GURL()),
  98       runner_(new Runner(this)) {
  99   VLOG(1) << "Created context:\n" << GetDebugString();
 100   gin::PerContextData* gin_data = gin::PerContextData::From(v8_context);
 101   CHECK(gin_data);  // may fail if the v8::Context hasn't been registered yet
 102   gin_data->set_runner(runner_.get());
 103 }
 104
 105 ScriptContext::~ScriptContext() {
 106   VLOG(1) << "Destroyed context for extension\n"
 107           << "  extension id: " << GetExtensionID() << "\n"
 108           << "  effective extension id: "
 109           << (effective_extension_.get() ? effective_extension_->id() : "");
 110   CHECK(!is_valid_) << "ScriptContexts must be invalidated before destruction";
 111 }
 112
 113 // static
 114 bool ScriptContext::IsSandboxedPage(const ExtensionSet& extensions,
 115                                     const GURL& url) {
 116   // TODO(kalman): This is checking the wrong thing. See comment in
 117   // HasAccessOrThrowError.
 118   if (url.SchemeIs(kExtensionScheme)) {
 119     const Extension* extension = extensions.GetByID(url.host());
 120     if (extension) {
 121       return SandboxedPageInfo::IsSandboxedPage(extension, url.path());
 122     }
 123   }
 124   return false;
 125 }
 126
 127 void ScriptContext::Invalidate() {
 128   CHECK(is_valid_);
 129   is_valid_ = false;
 130
 131   // TODO(kalman): Make ModuleSystem use AddInvalidationObserver.
 132   // Ownership graph is a bit weird here.
 133   if (module_system_)
 134     module_system_->Invalidate();
 135
 136   // Swap |invalidate_observers_| to a local variable to clear it, and to make
 137   // sure it's not mutated as we iterate.
 138   std::vector<base::Closure> observers;
 139   observers.swap(invalidate_observers_);
 140   for (const base::Closure& observer : observers) {
 141     observer.Run();
 142   }
 143   DCHECK(invalidate_observers_.empty())
 144       << "Invalidation observers cannot be added during invalidation";
 145
 146   runner_.reset();
 147   v8_context_.Reset();
 148 }
 149
 150 void ScriptContext::AddInvalidationObserver(const base::Closure& observer) {
 151   invalidate_observers_.push_back(observer);
 152 }
 153
 154 const std::string& ScriptContext::GetExtensionID() const {
 155   return extension_.get() ? extension_->id() : base::EmptyString();
 156 }
 157
 158 content::RenderView* ScriptContext::GetRenderView() const {
 159   if (web_frame_ && web_frame_->view())
 160     return content::RenderView::FromWebView(web_frame_->view());
 161   return NULL;
 162 }
 163
 164 content::RenderFrame* ScriptContext::GetRenderFrame() const {
 165   if (web_frame_)
 166     return content::RenderFrame::FromWebFrame(web_frame_);
 167   return NULL;
 168 }
 169
 170 v8::Local<v8::Value> ScriptContext::CallFunction(
 171     const v8::Local<v8::Function>& function,
 172     int argc,
 173     v8::Local<v8::Value> argv[]) const {
 174   v8::EscapableHandleScope handle_scope(isolate());
 175   v8::Context::Scope scope(v8_context());
 176
 177   blink::WebScopedMicrotaskSuppression suppression;
 178   if (!is_valid_) {
 179     return handle_scope.Escape(
 180         v8::Local<v8::Primitive>(v8::Undefined(isolate())));
 181   }
 182
 183   v8::Local<v8::Object> global = v8_context()->Global();
 184   if (!web_frame_)
 185     return handle_scope.Escape(function->Call(global, argc, argv));
 186   return handle_scope.Escape(
 187       v8::Local<v8::Value>(web_frame_->callFunctionEvenIfScriptDisabled(
 188           function, global, argc, argv)));
 189 }
 190
 191 v8::Local<v8::Value> ScriptContext::CallFunction(
 192     const v8::Local<v8::Function>& function) const {
 193   return CallFunction(function, 0, nullptr);
 194 }
 195
 196 Feature::Availability ScriptContext::GetAvailability(
 197     const std::string& api_name) {
 198   // Hack: Hosted apps should have the availability of messaging APIs based on
 199   // the URL of the page (which might have access depending on some extension
 200   // with externally_connectable), not whether the app has access to messaging
 201   // (which it won't).
 202   const Extension* extension = extension_.get();
 203   if (extension && extension->is_hosted_app() &&
 204       (api_name == "runtime.connect" || api_name == "runtime.sendMessage")) {
 205     extension = NULL;
 206   }
 207   return ExtensionAPI::GetSharedInstance()->IsAvailable(
 208       api_name, extension, context_type_, GetURL());
 209 }
 210
 211 void ScriptContext::DispatchEvent(const char* event_name,
 212                                   v8::Local<v8::Array> args) const {
 213   v8::HandleScope handle_scope(isolate());
 214   v8::Context::Scope context_scope(v8_context());
 215
 216   v8::Local<v8::Value> argv[] = {v8::String::NewFromUtf8(isolate(), event_name),
 217                                  args};
 218   module_system_->CallModuleMethod(
 219       kEventBindings, "dispatchEvent", arraysize(argv), argv);
 220 }
 221
 222 void ScriptContext::DispatchOnUnloadEvent() {
 223   v8::HandleScope handle_scope(isolate());
 224   v8::Context::Scope context_scope(v8_context());
 225   module_system_->CallModuleMethod("unload_event", "dispatch");
 226 }
 227
 228 std::string ScriptContext::GetContextTypeDescription() const {
 229   return GetContextTypeDescriptionString(context_type_);
 230 }
 231
 232 std::string ScriptContext::GetEffectiveContextTypeDescription() const {
 233   return GetContextTypeDescriptionString(effective_context_type_);
 234 }
 235
 236 GURL ScriptContext::GetURL() const {
 237   return url_;
 238 }
 239
 240 bool ScriptContext::IsAnyFeatureAvailableToContext(const Feature& api) {
 241   return ExtensionAPI::GetSharedInstance()->IsAnyFeatureAvailableToContext(
 242       api, extension(), context_type(), GetDataSourceURLForFrame(web_frame()));
 243 }
 244
 245 // static
 246 GURL ScriptContext::GetDataSourceURLForFrame(const blink::WebFrame* frame) {
 247   // Normally we would use frame->document().url() to determine the document's
 248   // URL, but to decide whether to inject a content script, we use the URL from
 249   // the data source. This "quirk" helps prevents content scripts from
 250   // inadvertently adding DOM elements to the compose iframe in Gmail because
 251   // the compose iframe's dataSource URL is about:blank, but the document URL
 252   // changes to match the parent document after Gmail document.writes into
 253   // it to create the editor.
 254   // http://code.google.com/p/chromium/issues/detail?id=86742
 255   blink::WebDataSource* data_source = frame->provisionalDataSource()
 256                                           ? frame->provisionalDataSource()
 257                                           : frame->dataSource();
 258   return data_source ? GURL(data_source->request().url()) : GURL();
 259 }
 260
 261 // static
 262 GURL ScriptContext::GetEffectiveDocumentURL(const blink::WebFrame* frame,
 263                                             const GURL& document_url,
 264                                             bool match_about_blank) {
 265   // Common scenario. If |match_about_blank| is false (as is the case in most
 266   // extensions), or if the frame is not an about:-page, just return
 267   // |document_url| (supposedly the URL of the frame).
 268   if (!match_about_blank || !document_url.SchemeIs(url::kAboutScheme))
 269     return document_url;
 270
 271   // Non-sandboxed about:blank and about:srcdoc pages inherit their security
 272   // origin from their parent frame/window. So, traverse the frame/window
 273   // hierarchy to find the closest non-about:-page and return its URL.
 274   const blink::WebFrame* parent = frame;
 275   do {
 276     parent = parent->parent() ? parent->parent() : parent->opener();
 277   } while (parent != NULL && !parent->document().isNull() &&
 278            GURL(parent->document().url()).SchemeIs(url::kAboutScheme));
 279
 280   if (parent && !parent->document().isNull()) {
 281     // Only return the parent URL if the frame can access it.
 282     const blink::WebDocument& parent_document = parent->document();
 283     if (frame->document().securityOrigin().canAccess(
 284             parent_document.securityOrigin()))
 285       return parent_document.url();
 286   }
 287   return document_url;
 288 }
 289
 290 ScriptContext* ScriptContext::GetContext() { return this; }
 291
 292 void ScriptContext::OnResponseReceived(const std::string& name,
 293                                        int request_id,
 294                                        bool success,
 295                                        const base::ListValue& response,
 296                                        const std::string& error) {
 297   v8::HandleScope handle_scope(isolate());
 298
 299   scoped_ptr<V8ValueConverter> converter(V8ValueConverter::create());
 300   v8::Local<v8::Value> argv[] = {
 301       v8::Integer::New(isolate(), request_id),
 302       v8::String::NewFromUtf8(isolate(), name.c_str()),
 303       v8::Boolean::New(isolate(), success),
 304       converter->ToV8Value(&response,
 305                            v8::Local<v8::Context>::New(isolate(), v8_context_)),
 306       v8::String::NewFromUtf8(isolate(), error.c_str())};
 307
 308   v8::Local<v8::Value> retval = module_system()->CallModuleMethod(
 309       "sendRequest", "handleResponse", arraysize(argv), argv);
 310
 311   // In debug, the js will validate the callback parameters and return a
 312   // string if a validation error has occured.
 313   DCHECK(retval.IsEmpty() || retval->IsUndefined())
 314       << *v8::String::Utf8Value(retval);
 315 }
 316
 317 void ScriptContext::SetContentCapabilities(
 318     const APIPermissionSet& permissions) {
 319   content_capabilities_ = permissions;
 320 }
 321
 322 bool ScriptContext::HasAPIPermission(APIPermission::ID permission) const {
 323   if (effective_extension_.get()) {
 324     return effective_extension_->permissions_data()->HasAPIPermission(
 325         permission);
 326   } else if (context_type() == Feature::WEB_PAGE_CONTEXT) {
 327     // Only web page contexts may be granted content capabilities. Other
 328     // contexts are either privileged WebUI or extensions with their own set of
 329     // permissions.
 330     if (content_capabilities_.find(permission) != content_capabilities_.end())
 331       return true;
 332   }
 333   return false;
 334 }
 335
 336 bool ScriptContext::HasAccessOrThrowError(const std::string& name) {
 337   // Theoretically[1] we could end up with bindings being injected into
 338   // sandboxed frames, for example content scripts. Don't let them execute API
 339   // functions.
 340   //
 341   // In any case, this check is silly. The frame's document's security origin
 342   // already tells us if it's sandboxed. The only problem is that until
 343   // crbug.com/466373 is fixed, we don't know the security origin up-front and
 344   // may not know it here, either.
 345   //
 346   // [1] citation needed. This ScriptContext should already be in a state that
 347   // doesn't allow this, from ScriptContextSet::ClassifyJavaScriptContext.
 348   if (extension() &&
 349       SandboxedPageInfo::IsSandboxedPage(extension(), url_.path())) {
 350     static const char kMessage[] =
 351         "%s cannot be used within a sandboxed frame.";
 352     std::string error_msg = base::StringPrintf(kMessage, name.c_str());
 353     isolate()->ThrowException(v8::Exception::Error(
 354         v8::String::NewFromUtf8(isolate(), error_msg.c_str())));
 355     return false;
 356   }
 357
 358   Feature::Availability availability = GetAvailability(name);
 359   if (!availability.is_available()) {
 360     isolate()->ThrowException(v8::Exception::Error(
 361         v8::String::NewFromUtf8(isolate(), availability.message().c_str())));
 362     return false;
 363   }
 364
 365   return true;
 366 }
 367
 368 std::string ScriptContext::GetDebugString() const {
 369   return base::StringPrintf(
 370       "  extension id:           %s\n"
 371       "  frame:                  %p\n"
 372       "  URL:                    %s\n"
 373       "  context_type:           %s\n"
 374       "  effective extension id: %s\n"
 375       "  effective context type: %s",
 376       extension_.get() ? extension_->id().c_str() : "(none)", web_frame_,
 377       GetURL().spec().c_str(), GetContextTypeDescription().c_str(),
 378       effective_extension_.get() ? effective_extension_->id().c_str()
 379                                  : "(none)",
 380       GetEffectiveContextTypeDescription().c_str());
 381 }
 382
 383 ScriptContext::Runner::Runner(ScriptContext* context) : context_(context) {
 384 }
 385
 386 void ScriptContext::Runner::Run(const std::string& source,
 387                                 const std::string& resource_name) {
 388   context_->module_system()->RunString(source, resource_name);
 389 }
 390
 391 v8::Local<v8::Value> ScriptContext::Runner::Call(
 392     v8::Local<v8::Function> function,
 393     v8::Local<v8::Value> receiver,
 394     int argc,
 395     v8::Local<v8::Value> argv[]) {
 396   return context_->CallFunction(function, argc, argv);
 397 }
 398
 399 gin::ContextHolder* ScriptContext::Runner::GetContextHolder() {
 400   v8::HandleScope handle_scope(context_->isolate());
 401   return gin::PerContextData::From(context_->v8_context())->context_holder();
 402 }
 403
 404 }  // namespace extensions