IPC: Add new classes required for attachment brokering.

The implementations of these classes are just stubs.

BUG=493414

Review URL: https://codereview.chromium.org/1180313007

Cr-Commit-Position: refs/heads/master@{#334676}

10 files changed, 220 insertions, 0 deletions

diff --git a/ipc/BUILD.gn b/ipc/BUILD.gn
index b756921..f5f6595 100644
--- a/ipc/BUILD.gn
+++ b/ipc/BUILD.gn
@@ -6,6 +6,12 @@ import("//testing/test.gni")
 
 component("ipc") {
   sources = [
+    "attachment_broker.h",
+    "attachment_broker_win.cc",
+    "attachment_broker_win.h",
+    "brokerable_attachment.cc",
+    "brokerable_attachment.h",
+    "handle_attachment_win.h",
     "ipc_channel.cc",
     "ipc_channel.h",
     "ipc_channel_common.cc",
diff --git a/ipc/attachment_broker.h b/ipc/attachment_broker.h
new file mode 100644
index 0000000..35a6386
--- /dev/null
+++ b/ipc/attachment_broker.h
@@ -0,0 +1,52 @@
+// Copyright 2015 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.
+
+#ifndef IPC_ATTACHMENT_BROKER_H_
+#define IPC_ATTACHMENT_BROKER_H_
+
+#include "base/macros.h"
+#include "base/process/process_handle.h"
+#include "ipc/brokerable_attachment.h"
+#include "ipc/ipc_export.h"
+
+namespace IPC {
+
+class AttachmentBroker;
+// Classes that inherit from this abstract base class are capable of
+// communicating with a broker to send and receive attachments to Chrome IPC
+// messages.
+class IPC_EXPORT SupportsAttachmentBrokering {
+ public:
+  // Returns an AttachmentBroker used to broker attachments of IPC messages to
+  // other processes. There must be exactly one AttachmentBroker per process.
+  virtual AttachmentBroker* GetAttachmentBroker() = 0;
+};
+
+// Responsible for brokering attachments to Chrome IPC messages. On platforms
+// that support attachment brokering, every IPC channel should have a reference
+// to a AttachmentBroker.
+class IPC_EXPORT AttachmentBroker {
+ public:
+  AttachmentBroker() {}
+  virtual ~AttachmentBroker() {}
+
+  // Sends |attachment| to |destination_process|. The implementation uses an
+  // IPC::Channel to communicate with the broker process. This may be the same
+  // IPC::Channel that is requesting the brokering of an attachment.
+  virtual void SendAttachmentToProcess(BrokerableAttachment* attachment,
+                                       base::ProcessId destination_process) = 0;
+
+  // Returns whether the attachment was available. If the attachment was
+  // available, populates the output parameter |attachment|. The caller then
+  // becomes the owner of |attachment|.
+  virtual bool GetAttachmentWithId(BrokerableAttachment::AttachmentId id,
+                                   BrokerableAttachment* attachment) = 0;
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(AttachmentBroker);
+};
+
+}  // namespace IPC
+
+#endif  // IPC_ATTACHMENT_BROKER_H_
diff --git a/ipc/attachment_broker_win.cc b/ipc/attachment_broker_win.cc
new file mode 100644
index 0000000..caf80b8
--- /dev/null
+++ b/ipc/attachment_broker_win.cc
@@ -0,0 +1,34 @@
+// Copyright 2015 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 "ipc/attachment_broker_win.h"
+
+namespace IPC {
+
+AttachmentBrokerWin::AttachmentBrokerWin() {
+}
+
+AttachmentBrokerWin::~AttachmentBrokerWin() {
+}
+
+void AttachmentBrokerWin::OnReceiveDuplicatedHandle(
+    HANDLE,
+    BrokerableAttachment::AttachmentId id) {
+  // TODO(erikchen): Implement me. http://crbug.com/493414
+}
+
+void AttachmentBrokerWin::SendAttachmentToProcess(
+    BrokerableAttachment* attachment,
+    base::ProcessId destination_process) {
+  // TODO(erikchen): Implement me. http://crbug.com/493414
+}
+
+bool AttachmentBrokerWin::GetAttachmentWithId(
+    BrokerableAttachment::AttachmentId id,
+    BrokerableAttachment* attachment) {
+  // TODO(erikchen): Implement me. http://crbug.com/493414
+  return false;
+}
+
+}  // namespace IPC
diff --git a/ipc/attachment_broker_win.h b/ipc/attachment_broker_win.h
new file mode 100644
index 0000000..8c021e7
--- /dev/null
+++ b/ipc/attachment_broker_win.h
@@ -0,0 +1,34 @@
+// Copyright 2015 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.
+
+#ifndef IPC_ATTACHMENT_BROKER_WIN_H_
+#define IPC_ATTACHMENT_BROKER_WIN_H_
+
+#include "ipc/attachment_broker.h"
+#include "ipc/ipc_export.h"
+#include "ipc/ipc_sender.h"
+
+namespace IPC {
+
+// This class is an implementation of AttachmentBroker for the Windows platform.
+class IPC_EXPORT AttachmentBrokerWin : public IPC::AttachmentBroker {
+ public:
+  AttachmentBrokerWin();
+  virtual ~AttachmentBrokerWin();
+
+  // In a non-broker process, the single instance of this class listens for
+  // an IPC from the broker process indicating that a new attachment has been
+  // duplicated.
+  void OnReceiveDuplicatedHandle(HANDLE, BrokerableAttachment::AttachmentId id);
+
+  // IPC::AttachmentBroker overrides.
+  void SendAttachmentToProcess(BrokerableAttachment* attachment,
+                               base::ProcessId destination_process) override;
+  bool GetAttachmentWithId(BrokerableAttachment::AttachmentId id,
+                           BrokerableAttachment* attachment) override;
+};
+
+}  // namespace IPC
+
+#endif  // IPC_ATTACHMENT_BROKER_WIN_H_
diff --git a/ipc/brokerable_attachment.cc b/ipc/brokerable_attachment.cc
new file mode 100644
index 0000000..be5d51b
--- /dev/null
+++ b/ipc/brokerable_attachment.cc
@@ -0,0 +1,19 @@
+// Copyright 2015 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 "ipc/brokerable_attachment.h"
+
+namespace IPC {
+
+BrokerableAttachment::BrokerableAttachment() {
+}
+
+BrokerableAttachment::~BrokerableAttachment() {
+}
+
+BrokerableAttachment::AttachmentId BrokerableAttachment::GetIdentifier() const {
+  return id_;
+}
+
+}  // namespace IPC
diff --git a/ipc/brokerable_attachment.h b/ipc/brokerable_attachment.h
new file mode 100644
index 0000000..42d8e9f
--- /dev/null
+++ b/ipc/brokerable_attachment.h
@@ -0,0 +1,41 @@
+// Copyright 2015 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.
+
+#ifndef IPC_BROKERABLE_ATTACHMENT_H_
+#define IPC_BROKERABLE_ATTACHMENT_H_
+
+#include <stdint.h>
+
+#include "base/macros.h"
+#include "ipc/ipc_export.h"
+#include "ipc/ipc_message_attachment.h"
+
+namespace IPC {
+
+// This subclass of MessageAttachment requires an AttachmentBroker to be
+// attached to a Chrome IPC message.
+class IPC_EXPORT BrokerableAttachment : public MessageAttachment {
+ public:
+  // An id uniquely identifies an attachment sent via a broker.
+  struct IPC_EXPORT AttachmentId {
+    uint32_t nonce[4];
+  };
+
+  // The identifier is unique across all Chrome processes.
+  AttachmentId GetIdentifier() const;
+
+ protected:
+  BrokerableAttachment();
+  ~BrokerableAttachment() override;
+
+ private:
+  // This member uniquely identifies a BrokerableAttachment across all Chrome
+  // processes.
+  AttachmentId id_;
+  DISALLOW_COPY_AND_ASSIGN(BrokerableAttachment);
+};
+
+}  // namespace IPC
+
+#endif  // IPC_BROKERABLE_ATTACHMENT_H_
diff --git a/ipc/handle_attachment_win.h b/ipc/handle_attachment_win.h
new file mode 100644
index 0000000..b539907
--- /dev/null
+++ b/ipc/handle_attachment_win.h
@@ -0,0 +1,24 @@
+// Copyright 2015 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.
+
+#ifndef IPC_HANDLE_ATTACHMENT_WIN_H_
+#define IPC_HANDLE_ATTACHMENT_WIN_H_
+
+#include "ipc/brokerable_attachment.h"
+#include "ipc/ipc_export.h"
+
+namespace IPC {
+namespace internal {
+
+// This class represents a Windows HANDLE attached to a Chrome IPC message.
+class IPC_EXPORT HandleAttachmentWin : public BrokerableAttachment {
+ private:
+  Type GetType() const override { return TYPE_WIN_HANDLE; }
+  HANDLE handle_;
+};
+
+}  // namespace internal
+}  // namespace IPC
+
+#endif  // IPC_HANDLE_ATTACHMENT_WIN_H_
diff --git a/ipc/ipc.gypi b/ipc/ipc.gypi
index a10790e..65979d1 100644
--- a/ipc/ipc.gypi
+++ b/ipc/ipc.gypi
@@ -11,6 +11,12 @@
       # This part is shared between the targets defined below.
       ['ipc_target==1', {
         'sources': [
+          'attachment_broker.h',
+          'attachment_broker_win.cc',
+          'attachment_broker_win.h',
+          'brokerable_attachment.cc',
+          'brokerable_attachment.h',
+          'handle_attachment_win.h',
           'ipc_channel.cc',
           'ipc_channel.h',
           'ipc_channel_factory.cc',
diff --git a/ipc/ipc_message_attachment.h b/ipc/ipc_message_attachment.h
index ba7f0e8..63dddfe 100644
--- a/ipc/ipc_message_attachment.h
+++ b/ipc/ipc_message_attachment.h
@@ -20,6 +20,7 @@ class IPC_EXPORT MessageAttachment
   enum Type {
     TYPE_PLATFORM_FILE,  // The instance is |PlatformFileAttachment|.
     TYPE_MOJO_HANDLE,    // The instance is |MojoHandleAttachment|.
+    TYPE_WIN_HANDLE,     // The instance is |HandleAttachmentWin|.
   };
 
   virtual Type GetType() const = 0;
diff --git a/ipc/mojo/ipc_channel_mojo.cc b/ipc/mojo/ipc_channel_mojo.cc
index d4e5260..62fcb19 100644
--- a/ipc/mojo/ipc_channel_mojo.cc
+++ b/ipc/mojo/ipc_channel_mojo.cc
@@ -532,6 +532,9 @@ MojoResult ChannelMojo::ReadFromMessageAttachmentSet(
                   attachment.get())->TakeHandle();
           handles->push_back(handle.release().value());
         } break;
+        case MessageAttachment::TYPE_WIN_HANDLE:
+          NOTREACHED();
+          break;
       }
     }