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/script_context.h"
  28 #include "extensions/renderer/script_context_set.h"
  29 #include "third_party/WebKit/public/web/WebDocument.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::Local<v8::Object> object,
 186                      v8::Local<v8::Function> callback,
 187                      v8::Isolate* isolate) {
 188       GCCallback* cb = new GCCallback(object, callback, isolate);
 189       cb->object_.SetWeak(cb, FirstWeakCallback,
 190                           v8::WeakCallbackType::kParameter);
 191     }
 192
 193    private:
 194     static void FirstWeakCallback(
 195         const v8::WeakCallbackInfo<GCCallback>& data) {
 196       // v8 says we need to explicitly reset weak handles from their callbacks.
 197       // It's not implicit as one might expect.
 198       data.GetParameter()->object_.Reset();
 199       data.SetSecondPassCallback(SecondWeakCallback);
 200     }
 201
 202     static void SecondWeakCallback(
 203         const v8::WeakCallbackInfo<GCCallback>& data) {
 204       base::MessageLoop::current()->PostTask(
 205           FROM_HERE,
 206           base::Bind(&GCCallback::RunCallback,
 207                      base::Owned(data.GetParameter())));
 208     }
 209
 210     GCCallback(v8::Local<v8::Object> object,
 211                v8::Local<v8::Function> callback,
 212                v8::Isolate* isolate)
 213         : object_(isolate, object),
 214           callback_(isolate, callback),
 215           isolate_(isolate) {}
 216
 217     void RunCallback() {
 218       v8::HandleScope handle_scope(isolate_);
 219       v8::Local<v8::Function> callback =
 220           v8::Local<v8::Function>::New(isolate_, callback_);
 221       v8::Local<v8::Context> context = callback->CreationContext();
 222       if (context.IsEmpty())
 223         return;
 224       v8::Context::Scope context_scope(context);
 225       blink::WebScopedMicrotaskSuppression suppression;
 226       callback->Call(context->Global(), 0, NULL);
 227     }
 228
 229     v8::Global<v8::Object> object_;
 230     v8::Global<v8::Function> callback_;
 231     v8::Isolate* isolate_;
 232
 233     DISALLOW_COPY_AND_ASSIGN(GCCallback);
 234   };
 235
 236   // void BindToGC(object, callback)
 237   //
 238   // Binds |callback| to be invoked *sometime after* |object| is garbage
 239   // collected. We don't call the method re-entrantly so as to avoid executing
 240   // JS in some bizarro undefined mid-GC state.
 241   void BindToGC(const v8::FunctionCallbackInfo<v8::Value>& args) {
 242     CHECK(args.Length() == 2 && args[0]->IsObject() && args[1]->IsFunction());
 243     GCCallback::Bind(args[0].As<v8::Object>(),
 244                      args[1].As<v8::Function>(),
 245                      args.GetIsolate());
 246   }
 247
 248   // Dispatcher handle. Not owned.
 249   Dispatcher* dispatcher_;
 250 };
 251
 252 void DispatchOnConnectToScriptContext(
 253     int target_port_id,
 254     const std::string& channel_name,
 255     const ExtensionMsg_TabConnectionInfo* source,
 256     const ExtensionMsg_ExternalConnectionInfo& info,
 257     const std::string& tls_channel_id,
 258     bool* port_created,
 259     ScriptContext* script_context) {
 260   // Only dispatch the events if this is the requested target frame (0 = main
 261   // frame; positive = child frame).
 262   content::RenderFrame* renderframe = script_context->GetRenderFrame();
 263   if (info.target_frame_id == 0 && renderframe->GetWebFrame()->parent() != NULL)
 264     return;
 265   if (info.target_frame_id > 0 &&
 266       renderframe->GetRoutingID() != info.target_frame_id)
 267     return;
 268   v8::Isolate* isolate = script_context->isolate();
 269   v8::HandleScope handle_scope(isolate);
 270
 271   scoped_ptr<V8ValueConverter> converter(V8ValueConverter::create());
 272
 273   const std::string& source_url_spec = info.source_url.spec();
 274   std::string target_extension_id = script_context->GetExtensionID();
 275   const Extension* extension = script_context->extension();
 276
 277   v8::Local<v8::Value> tab = v8::Null(isolate);
 278   v8::Local<v8::Value> tls_channel_id_value = v8::Undefined(isolate);
 279   v8::Local<v8::Value> guest_process_id = v8::Undefined(isolate);
 280
 281   if (extension) {
 282     if (!source->tab.empty() && !extension->is_platform_app())
 283       tab = converter->ToV8Value(&source->tab, script_context->v8_context());
 284
 285     ExternallyConnectableInfo* externally_connectable =
 286         ExternallyConnectableInfo::Get(extension);
 287     if (externally_connectable &&
 288         externally_connectable->accepts_tls_channel_id) {
 289       tls_channel_id_value = v8::String::NewFromUtf8(isolate,
 290                                                      tls_channel_id.c_str(),
 291                                                      v8::String::kNormalString,
 292                                                      tls_channel_id.size());
 293     }
 294
 295     if (info.guest_process_id != content::ChildProcessHost::kInvalidUniqueID)
 296       guest_process_id = v8::Integer::New(isolate, info.guest_process_id);
 297   }
 298
 299   v8::Local<v8::Value> arguments[] = {
 300       // portId
 301       v8::Integer::New(isolate, target_port_id),
 302       // channelName
 303       v8::String::NewFromUtf8(isolate, channel_name.c_str(),
 304                               v8::String::kNormalString, channel_name.size()),
 305       // sourceTab
 306       tab,
 307       // source_frame_id
 308       v8::Integer::New(isolate, source->frame_id),
 309       // guestProcessId
 310       guest_process_id,
 311       // sourceExtensionId
 312       v8::String::NewFromUtf8(isolate, info.source_id.c_str(),
 313                               v8::String::kNormalString, info.source_id.size()),
 314       // targetExtensionId
 315       v8::String::NewFromUtf8(isolate, target_extension_id.c_str(),
 316                               v8::String::kNormalString,
 317                               target_extension_id.size()),
 318       // sourceUrl
 319       v8::String::NewFromUtf8(isolate, source_url_spec.c_str(),
 320                               v8::String::kNormalString,
 321                               source_url_spec.size()),
 322       // tlsChannelId
 323       tls_channel_id_value,
 324   };
 325
 326   v8::Local<v8::Value> retval =
 327       script_context->module_system()->CallModuleMethod(
 328           "messaging", "dispatchOnConnect", arraysize(arguments), arguments);
 329
 330   if (!retval.IsEmpty()) {
 331     CHECK(retval->IsBoolean());
 332     *port_created |= retval->BooleanValue();
 333   } else {
 334     LOG(ERROR) << "Empty return value from dispatchOnConnect.";
 335   }
 336 }
 337
 338 void DeliverMessageToScriptContext(const Message& message,
 339                                    int target_port_id,
 340                                    ScriptContext* script_context) {
 341   v8::Isolate* isolate = script_context->isolate();
 342   v8::HandleScope handle_scope(isolate);
 343
 344   // Check to see whether the context has this port before bothering to create
 345   // the message.
 346   v8::Local<v8::Value> port_id_handle =
 347       v8::Integer::New(isolate, target_port_id);
 348   v8::Local<v8::Value> has_port =
 349       script_context->module_system()->CallModuleMethod("messaging", "hasPort",
 350                                                         1, &port_id_handle);
 351
 352   CHECK(!has_port.IsEmpty());
 353   if (!has_port->BooleanValue())
 354     return;
 355
 356   std::vector<v8::Local<v8::Value>> arguments;
 357   arguments.push_back(v8::String::NewFromUtf8(isolate,
 358                                               message.data.c_str(),
 359                                               v8::String::kNormalString,
 360                                               message.data.size()));
 361   arguments.push_back(port_id_handle);
 362
 363   scoped_ptr<blink::WebScopedUserGesture> web_user_gesture;
 364   scoped_ptr<blink::WebScopedWindowFocusAllowedIndicator> allow_window_focus;
 365   if (message.user_gesture) {
 366     web_user_gesture.reset(new blink::WebScopedUserGesture);
 367
 368     if (script_context->web_frame()) {
 369       blink::WebDocument document = script_context->web_frame()->document();
 370       allow_window_focus.reset(new blink::WebScopedWindowFocusAllowedIndicator(
 371           &document));
 372     }
 373   }
 374
 375   script_context->module_system()->CallModuleMethod(
 376       "messaging", "dispatchOnMessage", &arguments);
 377 }
 378
 379 void DispatchOnDisconnectToScriptContext(int port_id,
 380                                          const std::string& error_message,
 381                                          ScriptContext* script_context) {
 382   v8::Isolate* isolate = script_context->isolate();
 383   v8::HandleScope handle_scope(isolate);
 384
 385   std::vector<v8::Local<v8::Value>> arguments;
 386   arguments.push_back(v8::Integer::New(isolate, port_id));
 387   if (!error_message.empty()) {
 388     arguments.push_back(
 389         v8::String::NewFromUtf8(isolate, error_message.c_str()));
 390   } else {
 391     arguments.push_back(v8::Null(isolate));
 392   }
 393
 394   script_context->module_system()->CallModuleMethod(
 395       "messaging", "dispatchOnDisconnect", &arguments);
 396 }
 397
 398 }  // namespace
 399
 400 ObjectBackedNativeHandler* MessagingBindings::Get(Dispatcher* dispatcher,
 401                                                   ScriptContext* context) {
 402   return new ExtensionImpl(dispatcher, context);
 403 }
 404
 405 // static
 406 void MessagingBindings::DispatchOnConnect(
 407     const ScriptContextSet& context_set,
 408     int target_port_id,
 409     const std::string& channel_name,
 410     const ExtensionMsg_TabConnectionInfo& source,
 411     const ExtensionMsg_ExternalConnectionInfo& info,
 412     const std::string& tls_channel_id,
 413     content::RenderFrame* restrict_to_render_frame) {
 414   // TODO(robwu): ScriptContextSet.ForEach should accept RenderFrame*.
 415   content::RenderView* restrict_to_render_view =
 416       restrict_to_render_frame ? restrict_to_render_frame->GetRenderView()
 417                                : NULL;
 418   bool port_created = false;
 419   context_set.ForEach(
 420       info.target_id, restrict_to_render_view,
 421       base::Bind(&DispatchOnConnectToScriptContext, target_port_id,
 422                  channel_name, &source, info, tls_channel_id, &port_created));
 423
 424   // If we didn't create a port, notify the other end of the channel (treat it
 425   // as a disconnect).
 426   if (!port_created) {
 427     content::RenderThread::Get()->Send(new ExtensionHostMsg_CloseChannel(
 428         target_port_id, kReceivingEndDoesntExistError));
 429   }
 430 }
 431
 432 // static
 433 void MessagingBindings::DeliverMessage(
 434     const ScriptContextSet& context_set,
 435     int target_port_id,
 436     const Message& message,
 437     content::RenderFrame* restrict_to_render_frame) {
 438   // TODO(robwu): ScriptContextSet.ForEach should accept RenderFrame*.
 439   content::RenderView* restrict_to_render_view =
 440       restrict_to_render_frame ? restrict_to_render_frame->GetRenderView()
 441                                : NULL;
 442   context_set.ForEach(
 443       restrict_to_render_view,
 444       base::Bind(&DeliverMessageToScriptContext, message, target_port_id));
 445 }
 446
 447 // static
 448 void MessagingBindings::DispatchOnDisconnect(
 449     const ScriptContextSet& context_set,
 450     int port_id,
 451     const std::string& error_message,
 452     content::RenderFrame* restrict_to_render_frame) {
 453   // TODO(robwu): ScriptContextSet.ForEach should accept RenderFrame*.
 454   content::RenderView* restrict_to_render_view =
 455       restrict_to_render_frame ? restrict_to_render_frame->GetRenderView()
 456                                : NULL;
 457   context_set.ForEach(
 458       restrict_to_render_view,
 459       base::Bind(&DispatchOnDisconnectToScriptContext, port_id, error_message));
 460 }
 461
 462 }  // namespace extensions