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