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_urls.h"
  20 #include "extensions/common/features/base_feature_provider.h"
  21 #include "extensions/common/manifest_handlers/sandboxed_page_info.h"
  22 #include "extensions/common/permissions/permissions_data.h"
  23 #include "extensions/renderer/renderer_extension_registry.h"
  24 #include "extensions/renderer/v8_helpers.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     case Feature::SERVICE_WORKER_CONTEXT:
  58       return "SERVICE_WORKER";
  59   }
  60   NOTREACHED();
  61   return std::string();
  62 }
  63
  64 static std::string ToStringOrDefault(
  65     const v8::Local<v8::String>& v8_string,
  66     const std::string& dflt) {
  67   if (v8_string.IsEmpty())
  68     return dflt;
  69   std::string ascii_value = *v8::String::Utf8Value(v8_string);
  70   return ascii_value.empty() ? dflt : ascii_value;
  71 }
  72
  73 }  // namespace
  74
  75 // A gin::Runner that delegates to its ScriptContext.
  76 class ScriptContext::Runner : public gin::Runner {
  77  public:
  78   explicit Runner(ScriptContext* context);
  79
  80   // gin::Runner overrides.
  81   void Run(const std::string& source,
  82            const std::string& resource_name) override;
  83   v8::Local<v8::Value> Call(v8::Local<v8::Function> function,
  84                             v8::Local<v8::Value> receiver,
  85                             int argc,
  86                             v8::Local<v8::Value> argv[]) override;
  87   gin::ContextHolder* GetContextHolder() override;
  88
  89  private:
  90   ScriptContext* context_;
  91 };
  92
  93 ScriptContext::ScriptContext(const v8::Local<v8::Context>& v8_context,
  94                              blink::WebLocalFrame* web_frame,
  95                              const Extension* extension,
  96                              Feature::Context context_type,
  97                              const Extension* effective_extension,
  98                              Feature::Context effective_context_type)
  99     : is_valid_(true),
 100       v8_context_(v8_context->GetIsolate(), v8_context),
 101       web_frame_(web_frame),
 102       extension_(extension),
 103       context_type_(context_type),
 104       effective_extension_(effective_extension),
 105       effective_context_type_(effective_context_type),
 106       safe_builtins_(this),
 107       isolate_(v8_context->GetIsolate()),
 108       url_(web_frame_ ? GetDataSourceURLForFrame(web_frame_) : GURL()),
 109       runner_(new Runner(this)) {
 110   VLOG(1) << "Created context:\n" << GetDebugString();
 111   gin::PerContextData* gin_data = gin::PerContextData::From(v8_context);
 112   CHECK(gin_data);
 113   gin_data->set_runner(runner_.get());
 114 }
 115
 116 ScriptContext::~ScriptContext() {
 117   VLOG(1) << "Destroyed context for extension\n"
 118           << "  extension id: " << GetExtensionID() << "\n"
 119           << "  effective extension id: "
 120           << (effective_extension_.get() ? effective_extension_->id() : "");
 121   CHECK(!is_valid_) << "ScriptContexts must be invalidated before destruction";
 122 }
 123
 124 // static
 125 bool ScriptContext::IsSandboxedPage(const GURL& url) {
 126   // TODO(kalman): This is checking the wrong thing. See comment in
 127   // HasAccessOrThrowError.
 128   if (url.SchemeIs(kExtensionScheme)) {
 129     const Extension* extension =
 130         RendererExtensionRegistry::Get()->GetByID(url.host());
 131     if (extension) {
 132       return SandboxedPageInfo::IsSandboxedPage(extension, url.path());
 133     }
 134   }
 135   return false;
 136 }
 137
 138 void ScriptContext::Invalidate() {
 139   CHECK(is_valid_);
 140   is_valid_ = false;
 141
 142   // TODO(kalman): Make ModuleSystem use AddInvalidationObserver.
 143   // Ownership graph is a bit weird here.
 144   if (module_system_)
 145     module_system_->Invalidate();
 146
 147   // Swap |invalidate_observers_| to a local variable to clear it, and to make
 148   // sure it's not mutated as we iterate.
 149   std::vector<base::Closure> observers;
 150   observers.swap(invalidate_observers_);
 151   for (const base::Closure& observer : observers) {
 152     observer.Run();
 153   }
 154   DCHECK(invalidate_observers_.empty())
 155       << "Invalidation observers cannot be added during invalidation";
 156
 157   runner_.reset();
 158   v8_context_.Reset();
 159 }
 160
 161 void ScriptContext::AddInvalidationObserver(const base::Closure& observer) {
 162   invalidate_observers_.push_back(observer);
 163 }
 164
 165 const std::string& ScriptContext::GetExtensionID() const {
 166   return extension_.get() ? extension_->id() : base::EmptyString();
 167 }
 168
 169 content::RenderFrame* ScriptContext::GetRenderFrame() const {
 170   if (web_frame_)
 171     return content::RenderFrame::FromWebFrame(web_frame_);
 172   return NULL;
 173 }
 174
 175 v8::Local<v8::Value> ScriptContext::CallFunction(
 176     const v8::Local<v8::Function>& function,
 177     int argc,
 178     v8::Local<v8::Value> argv[]) const {
 179   v8::EscapableHandleScope handle_scope(isolate());
 180   v8::Context::Scope scope(v8_context());
 181
 182   blink::WebScopedMicrotaskSuppression suppression;
 183   if (!is_valid_) {
 184     return handle_scope.Escape(
 185         v8::Local<v8::Primitive>(v8::Undefined(isolate())));
 186   }
 187
 188   v8::Local<v8::Object> global = v8_context()->Global();
 189   if (!web_frame_)
 190     return handle_scope.Escape(function->Call(global, argc, argv));
 191   return handle_scope.Escape(
 192       v8::Local<v8::Value>(web_frame_->callFunctionEvenIfScriptDisabled(
 193           function, global, argc, argv)));
 194 }
 195
 196 v8::Local<v8::Value> ScriptContext::CallFunction(
 197     const v8::Local<v8::Function>& function) const {
 198   return CallFunction(function, 0, nullptr);
 199 }
 200
 201 Feature::Availability ScriptContext::GetAvailability(
 202     const std::string& api_name) {
 203   // Hack: Hosted apps should have the availability of messaging APIs based on
 204   // the URL of the page (which might have access depending on some extension
 205   // with externally_connectable), not whether the app has access to messaging
 206   // (which it won't).
 207   const Extension* extension = extension_.get();
 208   if (extension && extension->is_hosted_app() &&
 209       (api_name == "runtime.connect" || api_name == "runtime.sendMessage")) {
 210     extension = NULL;
 211   }
 212   return ExtensionAPI::GetSharedInstance()->IsAvailable(
 213       api_name, extension, context_type_, GetURL());
 214 }
 215
 216 void ScriptContext::DispatchEvent(const char* event_name,
 217                                   v8::Local<v8::Array> args) const {
 218   v8::HandleScope handle_scope(isolate());
 219   v8::Context::Scope context_scope(v8_context());
 220
 221   v8::Local<v8::Value> argv[] = {v8::String::NewFromUtf8(isolate(), event_name),
 222                                  args};
 223   module_system_->CallModuleMethod(
 224       kEventBindings, "dispatchEvent", arraysize(argv), argv);
 225 }
 226
 227 void ScriptContext::DispatchOnUnloadEvent() {
 228   v8::HandleScope handle_scope(isolate());
 229   v8::Context::Scope context_scope(v8_context());
 230   module_system_->CallModuleMethod("unload_event", "dispatch");
 231 }
 232
 233 std::string ScriptContext::GetContextTypeDescription() const {
 234   return GetContextTypeDescriptionString(context_type_);
 235 }
 236
 237 std::string ScriptContext::GetEffectiveContextTypeDescription() const {
 238   return GetContextTypeDescriptionString(effective_context_type_);
 239 }
 240
 241 GURL ScriptContext::GetURL() const {
 242   return url_;
 243 }
 244
 245 bool ScriptContext::IsAnyFeatureAvailableToContext(const Feature& api) {
 246   return ExtensionAPI::GetSharedInstance()->IsAnyFeatureAvailableToContext(
 247       api, extension(), context_type(), GetDataSourceURLForFrame(web_frame()));
 248 }
 249
 250 // static
 251 GURL ScriptContext::GetDataSourceURLForFrame(const blink::WebFrame* frame) {
 252   // Normally we would use frame->document().url() to determine the document's
 253   // URL, but to decide whether to inject a content script, we use the URL from
 254   // the data source. This "quirk" helps prevents content scripts from
 255   // inadvertently adding DOM elements to the compose iframe in Gmail because
 256   // the compose iframe's dataSource URL is about:blank, but the document URL
 257   // changes to match the parent document after Gmail document.writes into
 258   // it to create the editor.
 259   // http://code.google.com/p/chromium/issues/detail?id=86742
 260   blink::WebDataSource* data_source = frame->provisionalDataSource()
 261                                           ? frame->provisionalDataSource()
 262                                           : frame->dataSource();
 263   return data_source ? GURL(data_source->request().url()) : GURL();
 264 }
 265
 266 // static
 267 GURL ScriptContext::GetEffectiveDocumentURL(const blink::WebFrame* frame,
 268                                             const GURL& document_url,
 269                                             bool match_about_blank) {
 270   // Common scenario. If |match_about_blank| is false (as is the case in most
 271   // extensions), or if the frame is not an about:-page, just return
 272   // |document_url| (supposedly the URL of the frame).
 273   if (!match_about_blank || !document_url.SchemeIs(url::kAboutScheme))
 274     return document_url;
 275
 276   // Non-sandboxed about:blank and about:srcdoc pages inherit their security
 277   // origin from their parent frame/window. So, traverse the frame/window
 278   // hierarchy to find the closest non-about:-page and return its URL.
 279   const blink::WebFrame* parent = frame;
 280   do {
 281     parent = parent->parent() ? parent->parent() : parent->opener();
 282   } while (parent != NULL && !parent->document().isNull() &&
 283            GURL(parent->document().url()).SchemeIs(url::kAboutScheme));
 284
 285   if (parent && !parent->document().isNull()) {
 286     // Only return the parent URL if the frame can access it.
 287     const blink::WebDocument& parent_document = parent->document();
 288     if (frame->document().securityOrigin().canAccess(
 289             parent_document.securityOrigin()))
 290       return parent_document.url();
 291   }
 292   return document_url;
 293 }
 294
 295 ScriptContext* ScriptContext::GetContext() { return this; }
 296
 297 void ScriptContext::OnResponseReceived(const std::string& name,
 298                                        int request_id,
 299                                        bool success,
 300                                        const base::ListValue& response,
 301                                        const std::string& error) {
 302   v8::HandleScope handle_scope(isolate());
 303
 304   scoped_ptr<V8ValueConverter> converter(V8ValueConverter::create());
 305   v8::Local<v8::Value> argv[] = {
 306       v8::Integer::New(isolate(), request_id),
 307       v8::String::NewFromUtf8(isolate(), name.c_str()),
 308       v8::Boolean::New(isolate(), success),
 309       converter->ToV8Value(&response,
 310                            v8::Local<v8::Context>::New(isolate(), v8_context_)),
 311       v8::String::NewFromUtf8(isolate(), error.c_str())};
 312
 313   v8::Local<v8::Value> retval = module_system()->CallModuleMethod(
 314       "sendRequest", "handleResponse", arraysize(argv), argv);
 315
 316   // In debug, the js will validate the callback parameters and return a
 317   // string if a validation error has occured.
 318   DCHECK(retval.IsEmpty() || retval->IsUndefined())
 319       << *v8::String::Utf8Value(retval);
 320 }
 321
 322 void ScriptContext::SetContentCapabilities(
 323     const APIPermissionSet& permissions) {
 324   content_capabilities_ = permissions;
 325 }
 326
 327 bool ScriptContext::HasAPIPermission(APIPermission::ID permission) const {
 328   if (effective_extension_.get()) {
 329     return effective_extension_->permissions_data()->HasAPIPermission(
 330         permission);
 331   } else if (context_type() == Feature::WEB_PAGE_CONTEXT) {
 332     // Only web page contexts may be granted content capabilities. Other
 333     // contexts are either privileged WebUI or extensions with their own set of
 334     // permissions.
 335     if (content_capabilities_.find(permission) != content_capabilities_.end())
 336       return true;
 337   }
 338   return false;
 339 }
 340
 341 bool ScriptContext::HasAccessOrThrowError(const std::string& name) {
 342   // Theoretically[1] we could end up with bindings being injected into
 343   // sandboxed frames, for example content scripts. Don't let them execute API
 344   // functions.
 345   //
 346   // In any case, this check is silly. The frame's document's security origin
 347   // already tells us if it's sandboxed. The only problem is that until
 348   // crbug.com/466373 is fixed, we don't know the security origin up-front and
 349   // may not know it here, either.
 350   //
 351   // [1] citation needed. This ScriptContext should already be in a state that
 352   // doesn't allow this, from ScriptContextSet::ClassifyJavaScriptContext.
 353   if (extension() &&
 354       SandboxedPageInfo::IsSandboxedPage(extension(), url_.path())) {
 355     static const char kMessage[] =
 356         "%s cannot be used within a sandboxed frame.";
 357     std::string error_msg = base::StringPrintf(kMessage, name.c_str());
 358     isolate()->ThrowException(v8::Exception::Error(
 359         v8::String::NewFromUtf8(isolate(), error_msg.c_str())));
 360     return false;
 361   }
 362
 363   Feature::Availability availability = GetAvailability(name);
 364   if (!availability.is_available()) {
 365     isolate()->ThrowException(v8::Exception::Error(
 366         v8::String::NewFromUtf8(isolate(), availability.message().c_str())));
 367     return false;
 368   }
 369
 370   return true;
 371 }
 372
 373 std::string ScriptContext::GetDebugString() const {
 374   return base::StringPrintf(
 375       "  extension id:           %s\n"
 376       "  frame:                  %p\n"
 377       "  URL:                    %s\n"
 378       "  context_type:           %s\n"
 379       "  effective extension id: %s\n"
 380       "  effective context type: %s",
 381       extension_.get() ? extension_->id().c_str() : "(none)", web_frame_,
 382       GetURL().spec().c_str(), GetContextTypeDescription().c_str(),
 383       effective_extension_.get() ? effective_extension_->id().c_str()
 384                                  : "(none)",
 385       GetEffectiveContextTypeDescription().c_str());
 386 }
 387
 388 std::string ScriptContext::GetStackTraceAsString() const {
 389   v8::Local<v8::StackTrace> stack_trace =
 390       v8::StackTrace::CurrentStackTrace(isolate(), 10);
 391   if (stack_trace.IsEmpty() || stack_trace->GetFrameCount() <= 0) {
 392     return "    <no stack trace>";
 393   } else {
 394     std::string result;
 395     for (int i = 0; i < stack_trace->GetFrameCount(); ++i) {
 396       v8::Local<v8::StackFrame> frame = stack_trace->GetFrame(i);
 397       CHECK(!frame.IsEmpty());
 398       result += base::StringPrintf(
 399           "\n    at %s (%s:%d:%d)",
 400           ToStringOrDefault(frame->GetFunctionName(), "<anonymous>").c_str(),
 401           ToStringOrDefault(frame->GetScriptName(), "<anonymous>").c_str(),
 402           frame->GetLineNumber(),
 403           frame->GetColumn());
 404     }
 405     return result;
 406   }
 407 }
 408
 409 v8::Local<v8::Value> ScriptContext::RunScript(
 410     v8::Local<v8::String> name,
 411     v8::Local<v8::String> code,
 412     const RunScriptExceptionHandler& exception_handler) {
 413   v8::EscapableHandleScope handle_scope(isolate());
 414   v8::Context::Scope context_scope(v8_context());
 415
 416   // Prepend extensions:: to |name| so that internal code can be differentiated
 417   // from external code in stack traces. This has no effect on behaviour.
 418   std::string internal_name =
 419       base::StringPrintf("extensions::%s", *v8::String::Utf8Value(name));
 420
 421   if (internal_name.size() >= v8::String::kMaxLength) {
 422     NOTREACHED() << "internal_name is too long.";
 423     return v8::Undefined(isolate());
 424   }
 425
 426   blink::WebScopedMicrotaskSuppression suppression;
 427   v8::TryCatch try_catch(isolate());
 428   try_catch.SetCaptureMessage(true);
 429   v8::ScriptOrigin origin(
 430       v8_helpers::ToV8StringUnsafe(isolate(), internal_name.c_str()));
 431   v8::Local<v8::Script> script;
 432   if (!v8::Script::Compile(v8_context(), code, &origin).ToLocal(&script)) {
 433     exception_handler.Run(try_catch);
 434     return v8::Undefined(isolate());
 435   }
 436
 437   v8::Local<v8::Value> result;
 438   if (!script->Run(v8_context()).ToLocal(&result)) {
 439     exception_handler.Run(try_catch);
 440     return v8::Undefined(isolate());
 441   }
 442
 443   return handle_scope.Escape(result);
 444 }
 445
 446 ScriptContext::Runner::Runner(ScriptContext* context) : context_(context) {
 447 }
 448
 449 void ScriptContext::Runner::Run(const std::string& source,
 450                                 const std::string& resource_name) {
 451   context_->module_system()->RunString(source, resource_name);
 452 }
 453
 454 v8::Local<v8::Value> ScriptContext::Runner::Call(
 455     v8::Local<v8::Function> function,
 456     v8::Local<v8::Value> receiver,
 457     int argc,
 458     v8::Local<v8::Value> argv[]) {
 459   return context_->CallFunction(function, argc, argv);
 460 }
 461
 462 gin::ContextHolder* ScriptContext::Runner::GetContextHolder() {
 463   v8::HandleScope handle_scope(context_->isolate());
 464   return gin::PerContextData::From(context_->v8_context())->context_holder();
 465 }
 466
 467 }  // namespace extensions