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