src/chrome/renderer/extensions/messaging_bindings.cc

   1 // Copyright (c) 2012 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 "chrome/renderer/extensions/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 "chrome/common/extensions/api/messaging/message.h"
  17 #include "chrome/common/extensions/extension_messages.h"
  18 #include "chrome/common/extensions/manifest_handlers/externally_connectable.h"
  19 #include "chrome/common/extensions/message_bundle.h"
  20 #include "chrome/common/url_constants.h"
  21 #include "chrome/renderer/extensions/chrome_v8_context.h"
  22 #include "chrome/renderer/extensions/chrome_v8_context_set.h"
  23 #include "chrome/renderer/extensions/chrome_v8_extension.h"
  24 #include "chrome/renderer/extensions/dispatcher.h"
  25 #include "chrome/renderer/extensions/event_bindings.h"
  26 #include "chrome/renderer/extensions/scoped_persistent.h"
  27 #include "content/public/renderer/render_thread.h"
  28 #include "content/public/renderer/render_view.h"
  29 #include "content/public/renderer/v8_value_converter.h"
  30 #include "grit/renderer_resources.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 {
  51
  52 struct ExtensionData {
  53   struct PortData {
  54     int ref_count;  // how many contexts have a handle to this port
  55     PortData() : ref_count(0) {}
  56   };
  57   std::map<int, PortData> ports;  // port ID -> data
  58 };
  59
  60 static base::LazyInstance<ExtensionData> g_extension_data =
  61     LAZY_INSTANCE_INITIALIZER;
  62
  63 static bool HasPortData(int port_id) {
  64   return g_extension_data.Get().ports.find(port_id) !=
  65       g_extension_data.Get().ports.end();
  66 }
  67
  68 static ExtensionData::PortData& GetPortData(int port_id) {
  69   return g_extension_data.Get().ports[port_id];
  70 }
  71
  72 static void ClearPortData(int port_id) {
  73   g_extension_data.Get().ports.erase(port_id);
  74 }
  75
  76 const char kPortClosedError[] = "Attempting to use a disconnected port object";
  77 const char kReceivingEndDoesntExistError[] =
  78     "Could not establish connection. Receiving end does not exist.";
  79
  80 class ExtensionImpl : public extensions::ChromeV8Extension {
  81  public:
  82   explicit ExtensionImpl(extensions::Dispatcher* dispatcher,
  83                          extensions::ChromeV8Context* context)
  84       : extensions::ChromeV8Extension(dispatcher, context) {
  85     RouteFunction("CloseChannel",
  86         base::Bind(&ExtensionImpl::CloseChannel, base::Unretained(this)));
  87     RouteFunction("PortAddRef",
  88         base::Bind(&ExtensionImpl::PortAddRef, base::Unretained(this)));
  89     RouteFunction("PortRelease",
  90         base::Bind(&ExtensionImpl::PortRelease, base::Unretained(this)));
  91     RouteFunction("PostMessage",
  92         base::Bind(&ExtensionImpl::PostMessage, base::Unretained(this)));
  93     // TODO(fsamuel, kalman): Move BindToGC out of messaging natives.
  94     RouteFunction("BindToGC",
  95         base::Bind(&ExtensionImpl::BindToGC, base::Unretained(this)));
  96   }
  97
  98   virtual ~ExtensionImpl() {}
  99
 100   // Sends a message along the given channel.
 101   void PostMessage(const v8::FunctionCallbackInfo<v8::Value>& args) {
 102     content::RenderView* renderview = GetRenderView();
 103     if (!renderview)
 104       return;
 105
 106     // Arguments are (int32 port_id, string message).
 107     CHECK(args.Length() == 2 &&
 108           args[0]->IsInt32() &&
 109           args[1]->IsString());
 110
 111     int port_id = args[0]->Int32Value();
 112     if (!HasPortData(port_id)) {
 113       args.GetIsolate()->ThrowException(v8::Exception::Error(
 114           v8::String::NewFromUtf8(args.GetIsolate(), kPortClosedError)));
 115       return;
 116     }
 117
 118     renderview->Send(new ExtensionHostMsg_PostMessage(
 119         renderview->GetRoutingID(), port_id,
 120         extensions::Message(
 121             *v8::String::Utf8Value(args[1]),
 122             blink::WebUserGestureIndicator::isProcessingUserGesture())));
 123   }
 124
 125   // Forcefully disconnects a port.
 126   void CloseChannel(const v8::FunctionCallbackInfo<v8::Value>& args) {
 127     // Arguments are (int32 port_id, boolean notify_browser).
 128     CHECK_EQ(2, args.Length());
 129     CHECK(args[0]->IsInt32());
 130     CHECK(args[1]->IsBoolean());
 131
 132     int port_id = args[0]->Int32Value();
 133     if (!HasPortData(port_id))
 134       return;
 135
 136     // Send via the RenderThread because the RenderView might be closing.
 137     bool notify_browser = args[1]->BooleanValue();
 138     if (notify_browser) {
 139       content::RenderThread::Get()->Send(
 140           new ExtensionHostMsg_CloseChannel(port_id, std::string()));
 141     }
 142
 143     ClearPortData(port_id);
 144   }
 145
 146   // A new port has been created for a context.  This occurs both when script
 147   // opens a connection, and when a connection is opened to this script.
 148   void PortAddRef(const v8::FunctionCallbackInfo<v8::Value>& args) {
 149     // Arguments are (int32 port_id).
 150     CHECK_EQ(1, args.Length());
 151     CHECK(args[0]->IsInt32());
 152
 153     int port_id = args[0]->Int32Value();
 154     ++GetPortData(port_id).ref_count;
 155   }
 156
 157   // The frame a port lived in has been destroyed.  When there are no more
 158   // frames with a reference to a given port, we will disconnect it and notify
 159   // the other end of the channel.
 160   void PortRelease(const v8::FunctionCallbackInfo<v8::Value>& args) {
 161     // Arguments are (int32 port_id).
 162     CHECK_EQ(1, args.Length());
 163     CHECK(args[0]->IsInt32());
 164
 165     int port_id = args[0]->Int32Value();
 166     if (HasPortData(port_id) && --GetPortData(port_id).ref_count == 0) {
 167       // Send via the RenderThread because the RenderView might be closing.
 168       content::RenderThread::Get()->Send(
 169           new ExtensionHostMsg_CloseChannel(port_id, std::string()));
 170       ClearPortData(port_id);
 171     }
 172   }
 173
 174   // Holds a |callback| to run sometime after |object| is GC'ed. |callback| will
 175   // not be executed re-entrantly to avoid running JS in an unexpected state.
 176   class GCCallback {
 177    public:
 178     static void Bind(v8::Handle<v8::Object> object,
 179                      v8::Handle<v8::Function> callback,
 180                      v8::Isolate* isolate) {
 181       GCCallback* cb = new GCCallback(object, callback, isolate);
 182       cb->object_.SetWeak(cb, NearDeathCallback);
 183     }
 184
 185    private:
 186     static void NearDeathCallback(
 187         const v8::WeakCallbackData<v8::Object, GCCallback>& data) {
 188       // v8 says we need to explicitly reset weak handles from their callbacks.
 189       // It's not implicit as one might expect.
 190       data.GetParameter()->object_.reset();
 191       base::MessageLoop::current()->PostTask(
 192           FROM_HERE,
 193           base::Bind(&GCCallback::RunCallback,
 194                      base::Owned(data.GetParameter())));
 195     }
 196
 197     GCCallback(v8::Handle<v8::Object> object,
 198                v8::Handle<v8::Function> callback,
 199                v8::Isolate* isolate)
 200         : object_(object), callback_(callback), isolate_(isolate) {}
 201
 202     void RunCallback() {
 203       v8::HandleScope handle_scope(isolate_);
 204       v8::Handle<v8::Function> callback = callback_.NewHandle(isolate_);
 205       v8::Handle<v8::Context> context = callback->CreationContext();
 206       if (context.IsEmpty())
 207         return;
 208       v8::Context::Scope context_scope(context);
 209       blink::WebScopedMicrotaskSuppression suppression;
 210       callback->Call(context->Global(), 0, NULL);
 211     }
 212
 213     extensions::ScopedPersistent<v8::Object> object_;
 214     extensions::ScopedPersistent<v8::Function> callback_;
 215     v8::Isolate* isolate_;
 216
 217     DISALLOW_COPY_AND_ASSIGN(GCCallback);
 218   };
 219
 220   // void BindToGC(object, callback)
 221   //
 222   // Binds |callback| to be invoked *sometime after* |object| is garbage
 223   // collected. We don't call the method re-entrantly so as to avoid executing
 224   // JS in some bizarro undefined mid-GC state.
 225   void BindToGC(const v8::FunctionCallbackInfo<v8::Value>& args) {
 226     CHECK(args.Length() == 2 && args[0]->IsObject() && args[1]->IsFunction());
 227     GCCallback::Bind(args[0].As<v8::Object>(),
 228                      args[1].As<v8::Function>(),
 229                      args.GetIsolate());
 230   }
 231 };
 232
 233 }  // namespace
 234
 235 namespace extensions {
 236
 237 ChromeV8Extension* MessagingBindings::Get(
 238     Dispatcher* dispatcher,
 239     ChromeV8Context* context) {
 240   return new ExtensionImpl(dispatcher, context);
 241 }
 242
 243 // static
 244 void MessagingBindings::DispatchOnConnect(
 245     const ChromeV8ContextSet::ContextSet& contexts,
 246     int target_port_id,
 247     const std::string& channel_name,
 248     const base::DictionaryValue& source_tab,
 249     const std::string& source_extension_id,
 250     const std::string& target_extension_id,
 251     const GURL& source_url,
 252     const std::string& tls_channel_id,
 253     content::RenderView* restrict_to_render_view) {
 254   v8::Isolate* isolate = v8::Isolate::GetCurrent();
 255   v8::HandleScope handle_scope(isolate);
 256
 257   scoped_ptr<V8ValueConverter> converter(V8ValueConverter::create());
 258
 259   bool port_created = false;
 260   std::string source_url_spec = source_url.spec();
 261
 262   // TODO(kalman): pass in the full ChromeV8ContextSet; call ForEach.
 263   for (ChromeV8ContextSet::ContextSet::const_iterator it = contexts.begin();
 264        it != contexts.end(); ++it) {
 265     if (restrict_to_render_view &&
 266         restrict_to_render_view != (*it)->GetRenderView()) {
 267       continue;
 268     }
 269
 270     // TODO(kalman): remove when ContextSet::ForEach is available.
 271     if ((*it)->v8_context().IsEmpty())
 272       continue;
 273
 274     v8::Handle<v8::Value> tab = v8::Null(isolate);
 275     if (!source_tab.empty())
 276       tab = converter->ToV8Value(&source_tab, (*it)->v8_context());
 277
 278     v8::Handle<v8::Value> tls_channel_id_value = v8::Undefined(isolate);
 279     if ((*it)->extension()) {
 280       ExternallyConnectableInfo* externally_connectable =
 281           ExternallyConnectableInfo::Get((*it)->extension());
 282       if (externally_connectable &&
 283           externally_connectable->accepts_tls_channel_id) {
 284         tls_channel_id_value =
 285             v8::String::NewFromUtf8(isolate,
 286                                     tls_channel_id.c_str(),
 287                                     v8::String::kNormalString,
 288                                     tls_channel_id.size());
 289       }
 290     }
 291
 292     v8::Handle<v8::Value> arguments[] = {
 293       v8::Integer::New(isolate, target_port_id),
 294       v8::String::NewFromUtf8(isolate,
 295                               channel_name.c_str(),
 296                               v8::String::kNormalString,
 297                               channel_name.size()),
 298       tab, v8::String::NewFromUtf8(isolate,
 299                                    source_extension_id.c_str(),
 300                                    v8::String::kNormalString,
 301                                    source_extension_id.size()),
 302       v8::String::NewFromUtf8(isolate,
 303                               target_extension_id.c_str(),
 304                               v8::String::kNormalString,
 305                               target_extension_id.size()),
 306       v8::String::NewFromUtf8(isolate,
 307                               source_url_spec.c_str(),
 308                               v8::String::kNormalString,
 309                               source_url_spec.size()),
 310       tls_channel_id_value,
 311     };
 312
 313     v8::Handle<v8::Value> retval = (*it)->module_system()->CallModuleMethod(
 314         "messaging",
 315         "dispatchOnConnect",
 316         arraysize(arguments), arguments);
 317
 318     if (retval.IsEmpty()) {
 319       LOG(ERROR) << "Empty return value from dispatchOnConnect.";
 320       continue;
 321     }
 322
 323     CHECK(retval->IsBoolean());
 324     port_created |= retval->BooleanValue();
 325   }
 326
 327   // If we didn't create a port, notify the other end of the channel (treat it
 328   // as a disconnect).
 329   if (!port_created) {
 330     content::RenderThread::Get()->Send(
 331         new ExtensionHostMsg_CloseChannel(
 332             target_port_id, kReceivingEndDoesntExistError));
 333   }
 334 }
 335
 336 // static
 337 void MessagingBindings::DeliverMessage(
 338     const ChromeV8ContextSet::ContextSet& contexts,
 339     int target_port_id,
 340     const Message& message,
 341     content::RenderView* restrict_to_render_view) {
 342   scoped_ptr<blink::WebScopedUserGesture> web_user_gesture;
 343   scoped_ptr<blink::WebScopedWindowFocusAllowedIndicator> allow_window_focus;
 344   if (message.user_gesture) {
 345     web_user_gesture.reset(new blink::WebScopedUserGesture);
 346     allow_window_focus.reset(new blink::WebScopedWindowFocusAllowedIndicator);
 347   }
 348
 349   v8::Isolate* isolate = v8::Isolate::GetCurrent();
 350   v8::HandleScope handle_scope(isolate);
 351
 352   // TODO(kalman): pass in the full ChromeV8ContextSet; call ForEach.
 353   for (ChromeV8ContextSet::ContextSet::const_iterator it = contexts.begin();
 354        it != contexts.end(); ++it) {
 355     if (restrict_to_render_view &&
 356         restrict_to_render_view != (*it)->GetRenderView()) {
 357       continue;
 358     }
 359
 360     // TODO(kalman): remove when ContextSet::ForEach is available.
 361     if ((*it)->v8_context().IsEmpty())
 362       continue;
 363
 364     // Check to see whether the context has this port before bothering to create
 365     // the message.
 366     v8::Handle<v8::Value> port_id_handle =
 367         v8::Integer::New(isolate, target_port_id);
 368     v8::Handle<v8::Value> has_port = (*it)->module_system()->CallModuleMethod(
 369         "messaging",
 370         "hasPort",
 371         1, &port_id_handle);
 372
 373     CHECK(!has_port.IsEmpty());
 374     if (!has_port->BooleanValue())
 375       continue;
 376
 377     std::vector<v8::Handle<v8::Value> > arguments;
 378     arguments.push_back(v8::String::NewFromUtf8(isolate,
 379                                                 message.data.c_str(),
 380                                                 v8::String::kNormalString,
 381                                                 message.data.size()));
 382     arguments.push_back(port_id_handle);
 383     (*it)->module_system()->CallModuleMethod("messaging",
 384                                              "dispatchOnMessage",
 385                                              &arguments);
 386   }
 387 }
 388
 389 // static
 390 void MessagingBindings::DispatchOnDisconnect(
 391     const ChromeV8ContextSet::ContextSet& contexts,
 392     int port_id,
 393     const std::string& error_message,
 394     content::RenderView* restrict_to_render_view) {
 395   v8::Isolate* isolate = v8::Isolate::GetCurrent();
 396   v8::HandleScope handle_scope(isolate);
 397
 398   // TODO(kalman): pass in the full ChromeV8ContextSet; call ForEach.
 399   for (ChromeV8ContextSet::ContextSet::const_iterator it = contexts.begin();
 400        it != contexts.end(); ++it) {
 401     if (restrict_to_render_view &&
 402         restrict_to_render_view != (*it)->GetRenderView()) {
 403       continue;
 404     }
 405
 406     // TODO(kalman): remove when ContextSet::ForEach is available.
 407     if ((*it)->v8_context().IsEmpty())
 408       continue;
 409
 410     std::vector<v8::Handle<v8::Value> > arguments;
 411     arguments.push_back(v8::Integer::New(isolate, port_id));
 412     if (!error_message.empty()) {
 413       arguments.push_back(
 414           v8::String::NewFromUtf8(isolate, error_message.c_str()));
 415     } else {
 416       arguments.push_back(v8::Null(isolate));
 417     }
 418     (*it)->module_system()->CallModuleMethod("messaging",
 419                                              "dispatchOnDisconnect",
 420                                              &arguments);
 421   }
 422 }
 423
 424 }  // namespace extensions