extensions/renderer/messaging_bindings.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/messaging_bindings.h"
   6
   7 #include <map>
   8 #include <string>
   9
  10 #include "base/basictypes.h"
  11 #include "base/bind.h"
  12 #include "base/bind_helpers.h"
  13 #include "base/lazy_instance.h"
  14 #include "base/message_loop/message_loop.h"
  15 #include "base/values.h"
  16 #include "content/public/child/v8_value_converter.h"
  17 #include "content/public/common/child_process_host.h"
  18 #include "content/public/renderer/render_frame.h"
  19 #include "content/public/renderer/render_thread.h"
  20 #include "extensions/common/api/messaging/message.h"
  21 #include "extensions/common/extension_messages.h"
  22 #include "extensions/common/guest_view/guest_view_constants.h"
  23 #include "extensions/common/manifest_handlers/externally_connectable.h"
  24 #include "extensions/renderer/dispatcher.h"
  25 #include "extensions/renderer/event_bindings.h"
  26 #include "extensions/renderer/object_backed_native_handler.h"
  27 #include "extensions/renderer/scoped_persistent.h"
  28 #include "extensions/renderer/script_context.h"
  29 #include "extensions/renderer/script_context_set.h"
  30 #include "third_party/WebKit/public/web/WebLocalFrame.h"
  31 #include "third_party/WebKit/public/web/WebScopedMicrotaskSuppression.h"
  32 #include "third_party/WebKit/public/web/WebScopedUserGesture.h"
  33 #include "third_party/WebKit/public/web/WebScopedWindowFocusAllowedIndicator.h"
  34 #include "third_party/WebKit/public/web/WebUserGestureIndicator.h"
  35 #include "v8/include/v8.h"
  36
  37 // Message passing API example (in a content script):
  38 // var extension =
  39 //    new chrome.Extension('00123456789abcdef0123456789abcdef0123456');
  40 // var port = runtime.connect();
  41 // port.postMessage('Can you hear me now?');
  42 // port.onmessage.addListener(function(msg, port) {
  43 //   alert('response=' + msg);
  44 //   port.postMessage('I got your reponse');
  45 // });
  46
  47 using content::RenderThread;
  48 using content::V8ValueConverter;
  49
  50 namespace extensions {
  51
  52 namespace {
  53
  54 struct ExtensionData {
  55   struct PortData {
  56     int ref_count;  // how many contexts have a handle to this port
  57     PortData() : ref_count(0) {}
  58   };
  59   std::map<int, PortData> ports;  // port ID -> data
  60 };
  61
  62 base::LazyInstance<ExtensionData> g_extension_data = LAZY_INSTANCE_INITIALIZER;
  63
  64 bool HasPortData(int port_id) {
  65   return g_extension_data.Get().ports.find(port_id) !=
  66          g_extension_data.Get().ports.end();
  67 }
  68
  69 ExtensionData::PortData& GetPortData(int port_id) {
  70   return g_extension_data.Get().ports[port_id];
  71 }
  72
  73 void ClearPortData(int port_id) {
  74   g_extension_data.Get().ports.erase(port_id);
  75 }
  76
  77 const char kPortClosedError[] = "Attempting to use a disconnected port object";
  78 const char kReceivingEndDoesntExistError[] =
  79     "Could not establish connection. Receiving end does not exist.";
  80
  81 class ExtensionImpl : public ObjectBackedNativeHandler {
  82  public:
  83   ExtensionImpl(Dispatcher* dispatcher, ScriptContext* context)
  84       : ObjectBackedNativeHandler(context), dispatcher_(dispatcher) {
  85     RouteFunction(
  86         "CloseChannel",
  87         base::Bind(&ExtensionImpl::CloseChannel, base::Unretained(this)));
  88     RouteFunction(
  89         "PortAddRef",
  90         base::Bind(&ExtensionImpl::PortAddRef, base::Unretained(this)));
  91     RouteFunction(
  92         "PortRelease",
  93         base::Bind(&ExtensionImpl::PortRelease, base::Unretained(this)));
  94     RouteFunction(
  95         "PostMessage",
  96         base::Bind(&ExtensionImpl::PostMessage, base::Unretained(this)));
  97     // TODO(fsamuel, kalman): Move BindToGC out of messaging natives.
  98     RouteFunction("BindToGC",
  99                   base::Bind(&ExtensionImpl::BindToGC, base::Unretained(this)));
 100   }
 101
 102   ~ExtensionImpl() override {}
 103
 104  private:
 105   void ClearPortDataAndNotifyDispatcher(int port_id) {
 106     ClearPortData(port_id);
 107     dispatcher_->ClearPortData(port_id);
 108   }
 109
 110   // Sends a message along the given channel.
 111   void PostMessage(const v8::FunctionCallbackInfo<v8::Value>& args) {
 112     content::RenderFrame* renderframe = context()->GetRenderFrame();
 113     if (!renderframe)
 114       return;
 115
 116     // Arguments are (int32 port_id, string message).
 117     CHECK(args.Length() == 2 && args[0]->IsInt32() && args[1]->IsString());
 118
 119     int port_id = args[0]->Int32Value();
 120     if (!HasPortData(port_id)) {
 121       args.GetIsolate()->ThrowException(v8::Exception::Error(
 122           v8::String::NewFromUtf8(args.GetIsolate(), kPortClosedError)));
 123       return;
 124     }
 125
 126     renderframe->Send(new ExtensionHostMsg_PostMessage(
 127         renderframe->GetRoutingID(), port_id,
 128         Message(*v8::String::Utf8Value(args[1]),
 129                 blink::WebUserGestureIndicator::isProcessingUserGesture())));
 130   }
 131
 132   // Forcefully disconnects a port.
 133   void CloseChannel(const v8::FunctionCallbackInfo<v8::Value>& args) {
 134     // Arguments are (int32 port_id, boolean notify_browser).
 135     CHECK_EQ(2, args.Length());
 136     CHECK(args[0]->IsInt32());
 137     CHECK(args[1]->IsBoolean());
 138
 139     int port_id = args[0]->Int32Value();
 140     if (!HasPortData(port_id))
 141       return;
 142
 143     // Send via the RenderThread because the RenderFrame might be closing.
 144     bool notify_browser = args[1]->BooleanValue();
 145     if (notify_browser) {
 146       content::RenderThread::Get()->Send(
 147           new ExtensionHostMsg_CloseChannel(port_id, std::string()));
 148     }
 149
 150     ClearPortDataAndNotifyDispatcher(port_id);
 151   }
 152
 153   // A new port has been created for a context.  This occurs both when script
 154   // opens a connection, and when a connection is opened to this script.
 155   void PortAddRef(const v8::FunctionCallbackInfo<v8::Value>& args) {
 156     // Arguments are (int32 port_id).
 157     CHECK_EQ(1, args.Length());
 158     CHECK(args[0]->IsInt32());
 159
 160     int port_id = args[0]->Int32Value();
 161     ++GetPortData(port_id).ref_count;
 162   }
 163
 164   // The frame a port lived in has been destroyed.  When there are no more
 165   // frames with a reference to a given port, we will disconnect it and notify
 166   // the other end of the channel.
 167   void PortRelease(const v8::FunctionCallbackInfo<v8::Value>& args) {
 168     // Arguments are (int32 port_id).
 169     CHECK_EQ(1, args.Length());
 170     CHECK(args[0]->IsInt32());
 171
 172     int port_id = args[0]->Int32Value();
 173     if (HasPortData(port_id) && --GetPortData(port_id).ref_count == 0) {
 174       // Send via the RenderThread because the RenderFrame might be closing.
 175       content::RenderThread::Get()->Send(
 176           new ExtensionHostMsg_CloseChannel(port_id, std::string()));
 177       ClearPortDataAndNotifyDispatcher(port_id);
 178     }
 179   }
 180
 181   // Holds a |callback| to run sometime after |object| is GC'ed. |callback| will
 182   // not be executed re-entrantly to avoid running JS in an unexpected state.
 183   class GCCallback {
 184    public:
 185     static void Bind(v8::Handle<v8::Object> object,
 186                      v8::Handle<v8::Function> callback,
 187                      v8::Isolate* isolate) {
 188       GCCallback* cb = new GCCallback(object, callback, isolate);
 189       cb->object_.SetWeak(cb, NearDeathCallback);
 190     }
 191
 192    private:
 193     static void NearDeathCallback(
 194         const v8::WeakCallbackData<v8::Object, GCCallback>& data) {
 195       // v8 says we need to explicitly reset weak handles from their callbacks.
 196       // It's not implicit as one might expect.
 197       data.GetParameter()->object_.reset();
 198       base::MessageLoop::current()->PostTask(
 199           FROM_HERE,
 200           base::Bind(&GCCallback::RunCallback,
 201                      base::Owned(data.GetParameter())));
 202     }
 203
 204     GCCallback(v8::Handle<v8::Object> object,
 205                v8::Handle<v8::Function> callback,
 206                v8::Isolate* isolate)
 207         : object_(object), callback_(callback), isolate_(isolate) {}
 208
 209     void RunCallback() {
 210       v8::HandleScope handle_scope(isolate_);
 211       v8::Handle<v8::Function> callback = callback_.NewHandle(isolate_);
 212       v8::Handle<v8::Context> context = callback->CreationContext();
 213       if (context.IsEmpty())
 214         return;
 215       v8::Context::Scope context_scope(context);
 216       blink::WebScopedMicrotaskSuppression suppression;
 217       callback->Call(context->Global(), 0, NULL);
 218     }
 219
 220     ScopedPersistent<v8::Object> object_;
 221     ScopedPersistent<v8::Function> callback_;
 222     v8::Isolate* isolate_;
 223
 224     DISALLOW_COPY_AND_ASSIGN(GCCallback);
 225   };
 226
 227   // void BindToGC(object, callback)
 228   //
 229   // Binds |callback| to be invoked *sometime after* |object| is garbage
 230   // collected. We don't call the method re-entrantly so as to avoid executing
 231   // JS in some bizarro undefined mid-GC state.
 232   void BindToGC(const v8::FunctionCallbackInfo<v8::Value>& args) {
 233     CHECK(args.Length() == 2 && args[0]->IsObject() && args[1]->IsFunction());
 234     GCCallback::Bind(args[0].As<v8::Object>(),
 235                      args[1].As<v8::Function>(),
 236                      args.GetIsolate());
 237   }
 238
 239   // Dispatcher handle. Not owned.
 240   Dispatcher* dispatcher_;
 241 };
 242
 243 void DispatchOnConnectToScriptContext(
 244     int target_port_id,
 245     const std::string& channel_name,
 246     const ExtensionMsg_TabConnectionInfo* source,
 247     const ExtensionMsg_ExternalConnectionInfo& info,
 248     const std::string& tls_channel_id,
 249     bool* port_created,
 250     ScriptContext* script_context) {
 251   // Only dispatch the events if this is the requested target frame (0 = main
 252   // frame; positive = child frame).
 253   content::RenderFrame* renderframe = script_context->GetRenderFrame();
 254   if (info.target_frame_id == 0 && renderframe->GetWebFrame()->parent() != NULL)
 255     return;
 256   if (info.target_frame_id > 0 &&
 257       renderframe->GetRoutingID() != info.target_frame_id)
 258     return;
 259   v8::Isolate* isolate = script_context->isolate();
 260   v8::HandleScope handle_scope(isolate);
 261
 262   scoped_ptr<V8ValueConverter> converter(V8ValueConverter::create());
 263
 264   const std::string& source_url_spec = info.source_url.spec();
 265   std::string target_extension_id = script_context->GetExtensionID();
 266   const Extension* extension = script_context->extension();
 267
 268   v8::Handle<v8::Value> tab = v8::Null(isolate);
 269   v8::Handle<v8::Value> tls_channel_id_value = v8::Undefined(isolate);
 270   v8::Handle<v8::Value> guest_process_id = v8::Undefined(isolate);
 271
 272   if (extension) {
 273     if (!source->tab.empty() && !extension->is_platform_app())
 274       tab = converter->ToV8Value(&source->tab, script_context->v8_context());
 275
 276     ExternallyConnectableInfo* externally_connectable =
 277         ExternallyConnectableInfo::Get(extension);
 278     if (externally_connectable &&
 279         externally_connectable->accepts_tls_channel_id) {
 280       tls_channel_id_value = v8::String::NewFromUtf8(isolate,
 281                                                      tls_channel_id.c_str(),
 282                                                      v8::String::kNormalString,
 283                                                      tls_channel_id.size());
 284     }
 285
 286     if (info.guest_process_id != content::ChildProcessHost::kInvalidUniqueID)
 287       guest_process_id = v8::Integer::New(isolate, info.guest_process_id);
 288   }
 289
 290   v8::Handle<v8::Value> arguments[] = {
 291       // portId
 292       v8::Integer::New(isolate, target_port_id),
 293       // channelName
 294       v8::String::NewFromUtf8(isolate,
 295                               channel_name.c_str(),
 296                               v8::String::kNormalString,
 297                               channel_name.size()),
 298       // sourceTab
 299       tab,
 300       // source_frame_id
 301       v8::Integer::New(isolate, source->frame_id),
 302       // guestProcessId
 303       guest_process_id,
 304       // sourceExtensionId
 305       v8::String::NewFromUtf8(isolate,
 306                               info.source_id.c_str(),
 307                               v8::String::kNormalString,
 308                               info.source_id.size()),
 309       // targetExtensionId
 310       v8::String::NewFromUtf8(isolate,
 311                               target_extension_id.c_str(),
 312                               v8::String::kNormalString,
 313                               target_extension_id.size()),
 314       // sourceUrl
 315       v8::String::NewFromUtf8(isolate,
 316                               source_url_spec.c_str(),
 317                               v8::String::kNormalString,
 318                               source_url_spec.size()),
 319       // tlsChannelId
 320       tls_channel_id_value,
 321   };
 322
 323   v8::Handle<v8::Value> retval =
 324       script_context->module_system()->CallModuleMethod(
 325           "messaging", "dispatchOnConnect", arraysize(arguments), arguments);
 326
 327   if (!retval.IsEmpty()) {
 328     CHECK(retval->IsBoolean());
 329     *port_created |= retval->BooleanValue();
 330   } else {
 331     LOG(ERROR) << "Empty return value from dispatchOnConnect.";
 332   }
 333 }
 334
 335 void DeliverMessageToScriptContext(const std::string& message_data,
 336                                    int target_port_id,
 337                                    ScriptContext* script_context) {
 338   v8::Isolate* isolate = script_context->isolate();
 339   v8::HandleScope handle_scope(isolate);
 340
 341   // Check to see whether the context has this port before bothering to create
 342   // the message.
 343   v8::Handle<v8::Value> port_id_handle =
 344       v8::Integer::New(isolate, target_port_id);
 345   v8::Handle<v8::Value> has_port =
 346       script_context->module_system()->CallModuleMethod(
 347           "messaging", "hasPort", 1, &port_id_handle);
 348
 349   CHECK(!has_port.IsEmpty());
 350   if (!has_port->BooleanValue())
 351     return;
 352
 353   std::vector<v8::Handle<v8::Value> > arguments;
 354   arguments.push_back(v8::String::NewFromUtf8(isolate,
 355                                               message_data.c_str(),
 356                                               v8::String::kNormalString,
 357                                               message_data.size()));
 358   arguments.push_back(port_id_handle);
 359   script_context->module_system()->CallModuleMethod(
 360       "messaging", "dispatchOnMessage", &arguments);
 361 }
 362
 363 void DispatchOnDisconnectToScriptContext(int port_id,
 364                                          const std::string& error_message,
 365                                          ScriptContext* script_context) {
 366   v8::Isolate* isolate = script_context->isolate();
 367   v8::HandleScope handle_scope(isolate);
 368
 369   std::vector<v8::Handle<v8::Value> > arguments;
 370   arguments.push_back(v8::Integer::New(isolate, port_id));
 371   if (!error_message.empty()) {
 372     arguments.push_back(
 373         v8::String::NewFromUtf8(isolate, error_message.c_str()));
 374   } else {
 375     arguments.push_back(v8::Null(isolate));
 376   }
 377
 378   script_context->module_system()->CallModuleMethod(
 379       "messaging", "dispatchOnDisconnect", &arguments);
 380 }
 381
 382 }  // namespace
 383
 384 ObjectBackedNativeHandler* MessagingBindings::Get(Dispatcher* dispatcher,
 385                                                   ScriptContext* context) {
 386   return new ExtensionImpl(dispatcher, context);
 387 }
 388
 389 // static
 390 void MessagingBindings::DispatchOnConnect(
 391     const ScriptContextSet& context_set,
 392     int target_port_id,
 393     const std::string& channel_name,
 394     const ExtensionMsg_TabConnectionInfo& source,
 395     const ExtensionMsg_ExternalConnectionInfo& info,
 396     const std::string& tls_channel_id,
 397     content::RenderFrame* restrict_to_render_frame) {
 398   // TODO(robwu): ScriptContextSet.ForEach should accept RenderFrame*.
 399   content::RenderView* restrict_to_render_view =
 400       restrict_to_render_frame ? restrict_to_render_frame->GetRenderView()
 401                                : NULL;
 402   bool port_created = false;
 403   context_set.ForEach(
 404       info.target_id, restrict_to_render_view,
 405       base::Bind(&DispatchOnConnectToScriptContext, target_port_id,
 406                  channel_name, &source, info, tls_channel_id, &port_created));
 407
 408   // If we didn't create a port, notify the other end of the channel (treat it
 409   // as a disconnect).
 410   if (!port_created) {
 411     content::RenderThread::Get()->Send(new ExtensionHostMsg_CloseChannel(
 412         target_port_id, kReceivingEndDoesntExistError));
 413   }
 414 }
 415
 416 // static
 417 void MessagingBindings::DeliverMessage(
 418     const ScriptContextSet& context_set,
 419     int target_port_id,
 420     const Message& message,
 421     content::RenderFrame* restrict_to_render_frame) {
 422   scoped_ptr<blink::WebScopedUserGesture> web_user_gesture;
 423   scoped_ptr<blink::WebScopedWindowFocusAllowedIndicator> allow_window_focus;
 424   if (message.user_gesture) {
 425     web_user_gesture.reset(new blink::WebScopedUserGesture);
 426     allow_window_focus.reset(new blink::WebScopedWindowFocusAllowedIndicator);
 427   }
 428
 429   // TODO(robwu): ScriptContextSet.ForEach should accept RenderFrame*.
 430   content::RenderView* restrict_to_render_view =
 431       restrict_to_render_frame ? restrict_to_render_frame->GetRenderView()
 432                                : NULL;
 433   context_set.ForEach(
 434       restrict_to_render_view,
 435       base::Bind(&DeliverMessageToScriptContext, message.data, target_port_id));
 436 }
 437
 438 // static
 439 void MessagingBindings::DispatchOnDisconnect(
 440     const ScriptContextSet& context_set,
 441     int port_id,
 442     const std::string& error_message,
 443     content::RenderFrame* restrict_to_render_frame) {
 444   // TODO(robwu): ScriptContextSet.ForEach should accept RenderFrame*.
 445   content::RenderView* restrict_to_render_view =
 446       restrict_to_render_frame ? restrict_to_render_frame->GetRenderView()
 447                                : NULL;
 448   context_set.ForEach(
 449       restrict_to_render_view,
 450       base::Bind(&DispatchOnDisconnectToScriptContext, port_id, error_message));
 451 }
 452
 453 }  // namespace extensions