Native Messaging!

chrome/browser/extensions/api/messaging/message_service.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "chrome/browser/extensions/api/messaging/message_service.h"
 
 #include "base/atomic_sequence_num.h"
 #include "base/bind.h"
 #include "base/callback.h"
 #include "base/json/json_writer.h"
 #include "base/stl_util.h"
 #include "base/values.h"
+#include "chrome/browser/extensions/api/messaging/extension_message_port.h"
+#include "chrome/browser/extensions/api/messaging/native_message_port.h"
 #include "chrome/browser/extensions/extension_host.h"
 #include "chrome/browser/extensions/extension_process_manager.h"
 #include "chrome/browser/extensions/extension_service.h"
 #include "chrome/browser/extensions/extension_system.h"
 #include "chrome/browser/extensions/extension_tab_util.h"
 #include "chrome/browser/extensions/lazy_background_task_queue.h"
 #include "chrome/browser/extensions/process_map.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/tab_contents/tab_util.h"
 #include "chrome/browser/ui/tab_contents/tab_contents.h"
 #include "chrome/common/chrome_notification_types.h"
 #include "chrome/common/extensions/extension.h"
 #include "chrome/common/extensions/extension_messages.h"
 #include "chrome/common/view_type.h"
+#include "content/public/browser/browser_thread.h"
 #include "content/public/browser/notification_service.h"
 #include "content/public/browser/render_process_host.h"
 #include "content/public/browser/render_view_host.h"
 #include "content/public/browser/site_instance.h"
 #include "content/public/browser/web_contents.h"
 
 using content::SiteInstance;
 using content::WebContents;
 
 // Since we have 2 ports for every channel, we just index channels by half the
 // port ID.
 #define GET_CHANNEL_ID(port_id) ((port_id) / 2)
 #define GET_CHANNEL_OPENER_ID(channel_id) ((channel_id) * 2)
 #define GET_CHANNEL_RECEIVERS_ID(channel_id) ((channel_id) * 2 + 1)
 
 // Port1 is always even, port2 is always odd.
 #define IS_OPENER_PORT_ID(port_id) (((port_id) & 1) == 0)
 
 // Change even to odd and vice versa, to get the other side of a given channel.
 #define GET_OPPOSITE_PORT_ID(source_port_id) ((source_port_id) ^ 1)
 
 namespace extensions {
 
-struct MessageService::MessagePort {
-  content::RenderProcessHost* process;
-  int routing_id;
-  std::string extension_id;
-  void* background_host_ptr;  // used in IncrementLazyKeepaliveCount
-
-  MessagePort()
-     : process(NULL),
-       routing_id(MSG_ROUTING_CONTROL),
-       background_host_ptr(NULL) {}
-  MessagePort(content::RenderProcessHost* process,
-              int routing_id,
-              const std::string& extension_id)
-     : process(process),
-       routing_id(routing_id),
-       extension_id(extension_id),
-       background_host_ptr(NULL) {}
-};
-
 struct MessageService::MessageChannel {
-  MessageService::MessagePort opener;
-  MessageService::MessagePort receiver;
+  scoped_ptr<MessagePort> opener;
+  scoped_ptr<MessagePort> receiver;
 };
 
 struct MessageService::OpenChannelParams {
   content::RenderProcessHost* source;
   std::string tab_json;
-  MessagePort receiver;
+  scoped_ptr<MessagePort> receiver;
   int receiver_port_id;
   std::string source_extension_id;
   std::string target_extension_id;
   std::string channel_name;
 
+  // Takes ownership of receiver.
   OpenChannelParams(content::RenderProcessHost* source,
                     const std::string& tab_json,
-                    const MessagePort& receiver,
+                    MessagePort* receiver,
                     int receiver_port_id,
                     const std::string& source_extension_id,
                     const std::string& target_extension_id,
                     const std::string& channel_name)
       : source(source),
         tab_json(tab_json),
         receiver(receiver),
         receiver_port_id(receiver_port_id),
         source_extension_id(source_extension_id),
         target_extension_id(target_extension_id),
         channel_name(channel_name) {}
 };
 
 namespace {
 
 static base::StaticAtomicSequenceNumber g_next_channel_id;
 
-static void DispatchOnConnect(const MessageService::MessagePort& port,
-                              int dest_port_id,
-                              const std::string& channel_name,
-                              const std::string& tab_json,
-                              const std::string& source_extension_id,
-                              const std::string& target_extension_id) {
-  port.process->Send(new ExtensionMsg_DispatchOnConnect(
-      port.routing_id, dest_port_id, channel_name,
-      tab_json, source_extension_id, target_extension_id));
-}
-
-static void DispatchOnDisconnect(const MessageService::MessagePort& port,
-                                 int source_port_id,
-                                 bool connection_error) {
-  port.process->Send(new ExtensionMsg_DispatchOnDisconnect(
-      port.routing_id, source_port_id, connection_error));
-}
-
-static void DispatchOnMessage(const MessageService::MessagePort& port,
-                              const std::string& message,
-                              int target_port_id) {
-  port.process->Send(new ExtensionMsg_DeliverMessage(
-      port.routing_id, target_port_id, message));
-}
-
 static content::RenderProcessHost* GetExtensionProcess(
     Profile* profile, const std::string& extension_id) {
   SiteInstance* site_instance =
       profile->GetExtensionProcessManager()->GetSiteInstanceForURL(
           Extension::GetBaseURLFromExtensionId(extension_id));
 
   if (!site_instance->HasProcess())
     return NULL;
 
   return site_instance->GetProcess();
 }
 
-static void IncrementLazyKeepaliveCount(MessageService::MessagePort* port) {
-  Profile* profile =
-      Profile::FromBrowserContext(port->process->GetBrowserContext());
-  ExtensionProcessManager* pm =
-      ExtensionSystem::Get(profile)->process_manager();
-  ExtensionHost* host = pm->GetBackgroundHostForExtension(port->extension_id);
-  if (host && host->extension()->has_lazy_background_page())
-    pm->IncrementLazyKeepaliveCount(host->extension());
-
-  // Keep track of the background host, so when we decrement, we only do so if
-  // the host hasn't reloaded.
-  port->background_host_ptr = host;
-}
-
-static void DecrementLazyKeepaliveCount(MessageService::MessagePort* port) {
-  Profile* profile =
-      Profile::FromBrowserContext(port->process->GetBrowserContext());
-  ExtensionProcessManager* pm =
-      ExtensionSystem::Get(profile)->process_manager();
-  ExtensionHost* host = pm->GetBackgroundHostForExtension(port->extension_id);
-  if (host && host == port->background_host_ptr)
-    pm->DecrementLazyKeepaliveCount(host->extension());
-}
-
 }  // namespace
 
 // static
 void MessageService::AllocatePortIdPair(int* port1, int* port2) {
   int channel_id = g_next_channel_id.GetNext();
   int port1_id = channel_id * 2;
   int port2_id = channel_id * 2 + 1;
 
   // Sanity checks to make sure our channel<->port converters are correct.
   DCHECK(IS_OPENER_PORT_ID(port1_id));
   DCHECK(GET_OPPOSITE_PORT_ID(port1_id) == port2_id);
   DCHECK(GET_OPPOSITE_PORT_ID(port2_id) == port1_id);
   DCHECK(GET_CHANNEL_ID(port1_id) == GET_CHANNEL_ID(port2_id));
   DCHECK(GET_CHANNEL_ID(port1_id) == channel_id);
   DCHECK(GET_CHANNEL_OPENER_ID(channel_id) == port1_id);
   DCHECK(GET_CHANNEL_RECEIVERS_ID(channel_id) == port2_id);
 
   *port1 = port1_id;
   *port2 = port2_id;
 }
 
 MessageService::MessageService(
     LazyBackgroundTaskQueue* queue)
-    : lazy_background_task_queue_(queue) {
+    : lazy_background_task_queue_(queue),
+      weak_factory_(this) {
   registrar_.Add(this, content::NOTIFICATION_RENDERER_PROCESS_TERMINATED,
                  content::NotificationService::AllBrowserContextsAndSources());
   registrar_.Add(this, content::NOTIFICATION_RENDERER_PROCESS_CLOSED,
                  content::NotificationService::AllBrowserContextsAndSources());
 }
 
 MessageService::~MessageService() {
   STLDeleteContainerPairSecondPointers(channels_.begin(), channels_.end());
   channels_.clear();
 }
 
 void MessageService::OpenChannelToExtension(
     int source_process_id, int source_routing_id, int receiver_port_id,
     const std::string& source_extension_id,
     const std::string& target_extension_id,
     const std::string& channel_name) {
   content::RenderProcessHost* source =
       content::RenderProcessHost::FromID(source_process_id);
   if (!source)
     return;
   Profile* profile = Profile::FromBrowserContext(source->GetBrowserContext());
 
   // Note: we use the source's profile here. If the source is an incognito
   // process, we will use the incognito EPM to find the right extension process,
   // which depends on whether the extension uses spanning or split mode.
-  MessagePort receiver(GetExtensionProcess(profile, target_extension_id),
-                       MSG_ROUTING_CONTROL,
-                       target_extension_id);
+  MessagePort* receiver = new ExtensionMessagePort(
+      GetExtensionProcess(profile, target_extension_id), MSG_ROUTING_CONTROL,
+      target_extension_id);
   WebContents* source_contents = tab_util::GetWebContentsByID(
       source_process_id, source_routing_id);
 
   // Include info about the opener's tab (if it was a tab).
   std::string tab_json = "null";
   if (source_contents) {
     scoped_ptr<DictionaryValue> tab_value(
         ExtensionTabUtil::CreateTabValue(source_contents));
     base::JSONWriter::Write(tab_value.get(), &tab_json);
   }
 
-  OpenChannelParams params(source, tab_json, receiver, receiver_port_id,
-                           source_extension_id, target_extension_id,
-                           channel_name);
+  OpenChannelParams* params = new OpenChannelParams(source, tab_json, receiver,
+                                                    receiver_port_id,
+                                                    source_extension_id,
+                                                    target_extension_id,
+                                                    channel_name);
 
   // The target might be a lazy background page. In that case, we have to check
   // if it is loaded and ready, and if not, queue up the task and load the
   // page.
-  if (MaybeAddPendingOpenChannelTask(profile, params))
+  if (MaybeAddPendingOpenChannelTask(profile, params)) {
+    return;
+  }
+
+  OpenChannelImpl(scoped_ptr<OpenChannelParams>(params));
+}
+
+void MessageService::OpenChannelToNativeApp(
+    int source_process_id,
+    int source_routing_id,
+    int receiver_port_id,
+    const std::string& source_extension_id,
+    const std::string& native_app_name,
+    const std::string& channel_name,
+    const std::string& connect_message) {
+  content::RenderProcessHost* source =
+      content::RenderProcessHost::FromID(source_process_id);
+  if (!source)
     return;
 
-  OpenChannelImpl(params);
+  WebContents* source_contents = tab_util::GetWebContentsByID(
+      source_process_id, source_routing_id);
+
+  // Include info about the opener's tab (if it was a tab).
+  std::string tab_json = "null";
+  if (source_contents) {
+    scoped_ptr<DictionaryValue> tab_value(
+        ExtensionTabUtil::CreateTabValue(source_contents));
+    base::JSONWriter::Write(tab_value.get(), &tab_json);
+  }
+
+  scoped_ptr<MessageChannel> channel(new MessageChannel());
+  channel->opener.reset(new ExtensionMessagePort(source, MSG_ROUTING_CONTROL,
+                                                 source_extension_id));
+
+  NativeMessageProcessHost::MessageType type =
+      channel_name == "chrome.extension.sendNativeMessage" ?
+      NativeMessageProcessHost::TYPE_SEND_MESSAGE_REQUEST :
+      NativeMessageProcessHost::TYPE_CONNECT;
+
+  content::BrowserThread::PostTask(
+      content::BrowserThread::FILE,
+      FROM_HERE,
+      base::Bind(&NativeMessageProcessHost::Create,
+                 base::WeakPtr<NativeMessageProcessHost::Client>(
+                    weak_factory_.GetWeakPtr()),
+                 native_app_name, connect_message, receiver_port_id,
+                 type,
+                 base::Bind(&MessageService::FinalizeOpenChannelToNativeApp,
+                            weak_factory_.GetWeakPtr(),
+                            receiver_port_id,
+                            channel_name,
+                            base::Passed(&channel),
+                            tab_json)));
+}
+
+void MessageService::FinalizeOpenChannelToNativeApp(
+    int receiver_port_id,
+    const std::string& channel_name,
+    scoped_ptr<MessageChannel> channel,
+    const std::string& tab_json,
+    NativeMessageProcessHost::ScopedNativeMessageProcessHost native_process) {
+  DCHECK(content::BrowserThread::CurrentlyOn(content::BrowserThread::UI));
+
+  // Abandon the channel
+  if (!native_process.get()) {
+    LOG(ERROR) << "Failed to create native process.";
+    return;
+  }
+  channel->receiver.reset(new NativeMessagePort(native_process.release()));
+
+  // Keep the opener alive until the channel is closed.
+  channel->opener->IncrementLazyKeepaliveCount();
+
+  AddChannel(channel.release(), receiver_port_id);
 }
 
 void MessageService::OpenChannelToTab(
     int source_process_id, int source_routing_id, int receiver_port_id,
     int tab_id, const std::string& extension_id,
     const std::string& channel_name) {
   content::RenderProcessHost* source =
       content::RenderProcessHost::FromID(source_process_id);
   if (!source)
     return;
   Profile* profile = Profile::FromBrowserContext(source->GetBrowserContext());
 
   TabContents* contents = NULL;
-  MessagePort receiver;
+  scoped_ptr<MessagePort> receiver;
   if (ExtensionTabUtil::GetTabById(tab_id, profile, true,
                                    NULL, NULL, &contents, NULL)) {
-    receiver.process = contents->web_contents()->GetRenderProcessHost();
-    receiver.routing_id =
-        contents->web_contents()->GetRenderViewHost()->GetRoutingID();
-    receiver.extension_id = extension_id;
+    receiver.reset(new ExtensionMessagePort(
+        contents->web_contents()->GetRenderProcessHost(),
+        contents->web_contents()->GetRenderViewHost()->GetRoutingID(),
+        extension_id));
   }
 
   if (contents && contents->web_contents()->GetController().NeedsReload()) {
     // The tab isn't loaded yet. Don't attempt to connect. Treat this as a
     // disconnect.
-    DispatchOnDisconnect(MessagePort(source, MSG_ROUTING_CONTROL, extension_id),
-                         GET_OPPOSITE_PORT_ID(receiver_port_id), true);
+    ExtensionMessagePort port(source, MSG_ROUTING_CONTROL, extension_id);
+    port.DispatchOnDisconnect(GET_OPPOSITE_PORT_ID(receiver_port_id), true);
     return;
   }
 
   WebContents* source_contents = tab_util::GetWebContentsByID(
       source_process_id, source_routing_id);
 
   // Include info about the opener's tab (if it was a tab).
   std::string tab_json = "null";
   if (source_contents) {
     scoped_ptr<DictionaryValue> tab_value(
         ExtensionTabUtil::CreateTabValue(source_contents));
     base::JSONWriter::Write(tab_value.get(), &tab_json);
   }
 
-  OpenChannelParams params(source, tab_json, receiver, receiver_port_id,
-                           extension_id, extension_id, channel_name);
-  OpenChannelImpl(params);
+  scoped_ptr<OpenChannelParams> params(new OpenChannelParams(source, tab_json,
+                                                             receiver.release(),
+                                                             receiver_port_id,
+                                                             extension_id,
+                                                             extension_id,
+                                                             channel_name));
+  OpenChannelImpl(params.Pass());
 }
 
-bool MessageService::OpenChannelImpl(const OpenChannelParams& params) {
-  if (!params.source)
+bool MessageService::OpenChannelImpl(scoped_ptr<OpenChannelParams> params) {
+  if (!params->source)
     return false;  // Closed while in flight.
 
-  if (!params.receiver.process) {
+  if (!params->receiver.get() || !params->receiver->GetRenderProcessHost()) {
     // Treat it as a disconnect.
-    DispatchOnDisconnect(MessagePort(params.source, MSG_ROUTING_CONTROL, ""),
-                         GET_OPPOSITE_PORT_ID(params.receiver_port_id), true);
+    ExtensionMessagePort port(params->source, MSG_ROUTING_CONTROL, "");
+    port.DispatchOnDisconnect(GET_OPPOSITE_PORT_ID(params->receiver_port_id),
+                              true);
     return false;
   }
 
   // Add extra paranoid CHECKs, since we have crash reports of this being NULL.
   // http://code.google.com/p/chromium/issues/detail?id=19067
-  CHECK(params.receiver.process);
+  CHECK(params->receiver->GetRenderProcessHost());
 
   MessageChannel* channel(new MessageChannel);
-  channel->opener = MessagePort(params.source, MSG_ROUTING_CONTROL,
-                                params.source_extension_id);
-  channel->receiver = params.receiver;
+  channel->opener.reset(new ExtensionMessagePort(params->source,
+                                                 MSG_ROUTING_CONTROL,
+                                                 params->source_extension_id));
+  channel->receiver.reset(params->receiver.release());
 
-  CHECK(params.receiver.process);
+  CHECK(channel->receiver->GetRenderProcessHost());
 
-  int channel_id = GET_CHANNEL_ID(params.receiver_port_id);
+  AddChannel(channel, params->receiver_port_id);
+
+  CHECK(channel->receiver->GetRenderProcessHost());
+
+  // Send the connect event to the receiver.  Give it the opener's port ID (the
+  // opener has the opposite port ID).
+  channel->receiver->DispatchOnConnect(params->receiver_port_id,
+                                       params->channel_name, params->tab_json,
+                                       params->source_extension_id,
+                                       params->target_extension_id);
+
+  // Keep both ends of the channel alive until the channel is closed.
+  channel->opener->IncrementLazyKeepaliveCount();
+  channel->receiver->IncrementLazyKeepaliveCount();
+  return true;
+}
+
+void MessageService::AddChannel(MessageChannel* channel, int receiver_port_id) {
+  int channel_id = GET_CHANNEL_ID(receiver_port_id);
   CHECK(channels_.find(channel_id) == channels_.end());
   channels_[channel_id] = channel;
   pending_channels_.erase(channel_id);
-
-  CHECK(params.receiver.process);
-
-  // Send the connect event to the receiver.  Give it the opener's port ID (the
-  // opener has the opposite port ID).
-  DispatchOnConnect(params.receiver, params.receiver_port_id,
-                    params.channel_name, params.tab_json,
-                    params.source_extension_id, params.target_extension_id);
-
-  // Keep both ends of the channel alive until the channel is closed.
-  IncrementLazyKeepaliveCount(&channel->opener);
-  IncrementLazyKeepaliveCount(&channel->receiver);
-  return true;
 }
 
 void MessageService::CloseChannel(int port_id, bool connection_error) {
   // Note: The channel might be gone already, if the other side closed first.
   int channel_id = GET_CHANNEL_ID(port_id);
   MessageChannelMap::iterator it = channels_.find(channel_id);
   if (it == channels_.end()) {
     PendingChannelMap::iterator pending = pending_channels_.find(channel_id);
     if (pending != pending_channels_.end()) {
       lazy_background_task_queue_->AddPendingTask(
           pending->second.first, pending->second.second,
           base::Bind(&MessageService::PendingCloseChannel,
-                     base::Unretained(this), port_id, connection_error));
+                     weak_factory_.GetWeakPtr(), port_id, connection_error));
     }
     return;
   }
   CloseChannelImpl(it, port_id, connection_error, true);
 }
 
 void MessageService::CloseChannelImpl(
     MessageChannelMap::iterator channel_iter, int closing_port_id,
     bool connection_error, bool notify_other_port) {
   MessageChannel* channel = channel_iter->second;
 
   // Notify the other side.
   if (notify_other_port) {
-    const MessagePort& port = IS_OPENER_PORT_ID(closing_port_id) ?
-        channel->receiver : channel->opener;
-    DispatchOnDisconnect(port, GET_OPPOSITE_PORT_ID(closing_port_id),
-                         connection_error);
+    MessagePort* port = IS_OPENER_PORT_ID(closing_port_id) ?
+        channel->receiver.get() : channel->opener.get();
+    port->DispatchOnDisconnect(GET_OPPOSITE_PORT_ID(closing_port_id),
+                               connection_error);
   }
 
-  // Balance the addrefs in OpenChannelImpl.
-  DecrementLazyKeepaliveCount(&channel->opener);
-  DecrementLazyKeepaliveCount(&channel->receiver);
+  // Balance the IncrementLazyKeepaliveCount() in OpenChannelImpl.
+  channel->opener->DecrementLazyKeepaliveCount();
+  channel->receiver->DecrementLazyKeepaliveCount();
 
   delete channel_iter->second;
   channels_.erase(channel_iter);
 }
 
-void MessageService::PostMessageFromRenderer(
+void MessageService::PostMessage(
     int source_port_id, const std::string& message) {
   int channel_id = GET_CHANNEL_ID(source_port_id);
   MessageChannelMap::iterator iter = channels_.find(channel_id);
   if (iter == channels_.end()) {
     // If this channel is pending, queue up the PostMessage to run once
     // the channel opens.
     PendingChannelMap::iterator pending = pending_channels_.find(channel_id);
     if (pending != pending_channels_.end()) {
       lazy_background_task_queue_->AddPendingTask(
           pending->second.first, pending->second.second,
           base::Bind(&MessageService::PendingPostMessage,
-                     base::Unretained(this), source_port_id, message));
+                     weak_factory_.GetWeakPtr(), source_port_id, message));
     }
     return;
   }
 
   // Figure out which port the ID corresponds to.
   int dest_port_id = GET_OPPOSITE_PORT_ID(source_port_id);
-  const MessagePort& port = IS_OPENER_PORT_ID(dest_port_id) ?
-      iter->second->opener : iter->second->receiver;
+  MessagePort* port = IS_OPENER_PORT_ID(dest_port_id) ?
+      iter->second->opener.get() : iter->second->receiver.get();
 
-  DispatchOnMessage(port, message, dest_port_id);
+  port->DispatchOnMessage(message, dest_port_id);
 }
 
 void MessageService::Observe(int type,
                              const content::NotificationSource& source,
                              const content::NotificationDetails& details) {
   switch (type) {
     case content::NOTIFICATION_RENDERER_PROCESS_TERMINATED:
     case content::NOTIFICATION_RENDERER_PROCESS_CLOSED: {
       content::RenderProcessHost* renderer =
           content::Source<content::RenderProcessHost>(source).ptr();
       OnProcessClosed(renderer);
       break;
     }
     default:
       NOTREACHED();
       return;
   }
 }
 
 void MessageService::OnProcessClosed(content::RenderProcessHost* process) {
   // Close any channels that share this renderer.  We notify the opposite
   // port that his pair has closed.
   for (MessageChannelMap::iterator it = channels_.begin();
        it != channels_.end(); ) {
     MessageChannelMap::iterator current = it++;
-    // If both sides are the same renderer, and it is closing, there is no
-    // "other" port, so there's no need to notify it.
-    bool notify_other_port =
-        current->second->opener.process != current->second->receiver.process;
 
-    if (current->second->opener.process == process) {
+    content::RenderProcessHost* opener_process =
+        current->second->opener->GetRenderProcessHost();
+    content::RenderProcessHost* receiver_process =
+        current->second->receiver->GetRenderProcessHost();
+
+    bool notify_other_port = opener_process &&
+        opener_process == receiver_process;
+
+    if (opener_process == process) {
       CloseChannelImpl(current, GET_CHANNEL_OPENER_ID(current->first),
-                       false, notify_other_port);
-    } else if (current->second->receiver.process == process) {
+                      false, notify_other_port);
+    } else if (receiver_process == process) {
       CloseChannelImpl(current, GET_CHANNEL_RECEIVERS_ID(current->first),
-                       false, notify_other_port);
+                      false, notify_other_port);
     }
   }
 }
 
 bool MessageService::MaybeAddPendingOpenChannelTask(
     Profile* profile,
-    const OpenChannelParams& params) {
+    OpenChannelParams* params) {
   ExtensionService* service = profile->GetExtensionService();
-  const std::string& extension_id = params.target_extension_id;
-  const Extension* extension = service->extensions()->GetByID(
-      extension_id);
+  const std::string& extension_id = params->target_extension_id;
+  const Extension* extension = service->extensions()->GetByID(extension_id);
   if (extension && extension->has_lazy_background_page()) {
     // If the extension uses spanning incognito mode, make sure we're always
     // using the original profile since that is what the extension process
     // will use.
     if (!extension->incognito_split_mode())
       profile = profile->GetOriginalProfile();
 
     if (lazy_background_task_queue_->ShouldEnqueueTask(profile, extension)) {
+      pending_channels_[GET_CHANNEL_ID(params->receiver_port_id)] =
+          PendingChannel(profile, extension_id);
+      scoped_ptr<OpenChannelParams> scoped_params(params);
       lazy_background_task_queue_->AddPendingTask(profile, extension_id,
           base::Bind(&MessageService::PendingOpenChannel,
-                     base::Unretained(this), params, params.source->GetID()));
-      pending_channels_[GET_CHANNEL_ID(params.receiver_port_id)] =
-          PendingChannel(profile, extension_id);
+                     weak_factory_.GetWeakPtr(), base::Passed(&scoped_params),
+                     params->source->GetID()));
       return true;
     }
   }
 
   return false;
 }
 
-void MessageService::PendingOpenChannel(const OpenChannelParams& params_in,
+void MessageService::PendingOpenChannel(scoped_ptr<OpenChannelParams> params,
                                         int source_process_id,
                                         ExtensionHost* host) {
   if (!host)
     return;  // TODO(mpcomplete): notify source of disconnect?
 
   // Re-lookup the source process since it may no longer be valid.
-  OpenChannelParams params = params_in;
-  params.source = content::RenderProcessHost::FromID(source_process_id);
-  if (!params.source)
+  content::RenderProcessHost* source =
+      content::RenderProcessHost::FromID(source_process_id);
+  if (!source)
     return;
 
-  params.receiver = MessagePort(host->render_process_host(),
-                                MSG_ROUTING_CONTROL,
-                                params.target_extension_id);
-  OpenChannelImpl(params);
+  params->source = source;
+  params->receiver.reset(new ExtensionMessagePort(host->render_process_host(),
+                                                  MSG_ROUTING_CONTROL,
+                                                  params->target_extension_id));
+  OpenChannelImpl(params.Pass());
 }
 
 }  // namespace extensions