mac: Add auto-close and share-read-only functionality to SharedMemory.

ipc/attachment_broker_mac_unittest.cc

 // 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 "build/build_config.h"
 
 #include <fcntl.h>
 #include <sys/mman.h>
 
 #include "base/command_line.h"
@@ skipping 93 matching lines @@
     return false;
   }
 
   *handle1 = base::get<0>(p);
   *handle2 = base::get<1>(p);
   return true;
 }
 
 // Returns |nullptr| on error.
 scoped_ptr<base::SharedMemory> MapSharedMemoryHandle(
-    const base::SharedMemoryHandle& shm) {
+    const base::SharedMemoryHandle& shm,
+    bool read_only) {
   if (!shm.IsValid()) {
     LOG(ERROR) << "Invalid SharedMemoryHandle";
     return nullptr;
   }
 
   size_t size;
   if (!shm.GetSize(&size)) {
     LOG(ERROR) << "Couldn't get size of SharedMemoryHandle";
     return nullptr;
   }
 
   scoped_ptr<base::SharedMemory> shared_memory(
-      new base::SharedMemory(shm, false));
+      new base::SharedMemory(shm, read_only));
   shared_memory->Map(size);
   return shared_memory;
 }
 
 // This method maps the SharedMemoryHandle, checks the contents, and then
 // consumes a reference to the underlying Mach port.
 bool CheckContentsOfSharedMemoryHandle(const base::SharedMemoryHandle& shm,
                                        const std::string& contents) {
-  scoped_ptr<base::SharedMemory> shared_memory(MapSharedMemoryHandle(shm));
+  scoped_ptr<base::SharedMemory> shared_memory(
+      MapSharedMemoryHandle(shm, false));
 
   if (memcmp(shared_memory->memory(), contents.c_str(), contents.size()) != 0) {
     LOG(ERROR) << "Shared Memory contents not equivalent";
     return false;
   }
   return true;
 }
 
 // This method mmaps the FileDescriptor, checks the contents, and then munmaps
 // the FileDescriptor and closes the underlying fd.
@@ skipping 34 matching lines @@
   return base::FileDescriptor(fd_closer.release(), true);
 }
 
 // Maps both handles, then checks that their contents matches |contents|. Then
 // checks that changes to one are reflected in the other. Then consumes
 // references to both underlying Mach ports.
 bool CheckContentsOfTwoEquivalentSharedMemoryHandles(
     const base::SharedMemoryHandle& handle1,
     const base::SharedMemoryHandle& handle2,
     const std::string& contents) {
-  scoped_ptr<base::SharedMemory> shared_memory1(MapSharedMemoryHandle(handle1));
-  scoped_ptr<base::SharedMemory> shared_memory2(MapSharedMemoryHandle(handle2));
+  scoped_ptr<base::SharedMemory> shared_memory1(
+      MapSharedMemoryHandle(handle1, false));
+  scoped_ptr<base::SharedMemory> shared_memory2(
+      MapSharedMemoryHandle(handle2, false));
 
   if (memcmp(shared_memory1->memory(), contents.c_str(), contents.size()) !=
       0) {
     LOG(ERROR) << "Incorrect contents in shared_memory1";
     return false;
   }
 
   if (memcmp(shared_memory1->memory(), shared_memory2->memory(),
              contents.size()) != 0) {
     LOG(ERROR) << "Incorrect contents in shared_memory2";
@@ skipping 690 matching lines @@
   bool success = CheckContentsOfMessage1(message, kDataBuffer1);
   SendControlMessage(sender, success);
 }
 
 MULTIPROCESS_IPC_TEST_CLIENT_MAIN(SendSharedMemoryHandleChannelProxy) {
   return CommonPrivilegedProcessMain(
       &SendSharedMemoryHandleChannelProxyCallback,
       "SendSharedMemoryHandleChannelProxy");
 }
 
+// Similar to SendSharedMemoryHandle, but first makes a copy of the handle using
+// ShareToProcess().
+TEST_F(IPCAttachmentBrokerMacTest, ShareToProcess) {
+  CommonSetUp("ShareToProcess");
+
+  {
+    scoped_ptr<base::SharedMemory> shared_memory(
+        MakeSharedMemory(kDataBuffer1));
+    base::SharedMemoryHandle new_handle;
+    ASSERT_TRUE(shared_memory->ShareToProcess(0, &new_handle));
+    IPC::Message* message =
+        new TestSharedMemoryHandleMsg1(100, new_handle, 200);
+    sender()->Send(message);
+  }
+
+  base::MessageLoop::current()->Run();
+  CommonTearDown();
+}
+
+void ShareToProcessCallback(IPC::Sender* sender, const IPC::Message& message) {
+  bool success = CheckContentsOfMessage1(message, kDataBuffer1);
+  SendControlMessage(sender, success);
+}
+
+MULTIPROCESS_IPC_TEST_CLIENT_MAIN(ShareToProcess) {
+  return CommonPrivilegedProcessMain(&ShareToProcessCallback, "ShareToProcess");
+}
+
+// Similar to ShareToProcess, but instead shares the memory object only with
+// read permissions.
+TEST_F(IPCAttachmentBrokerMacTest, ShareReadOnlyToProcess) {
+  CommonSetUp("ShareReadOnlyToProcess");
+
+  {
+    scoped_ptr<base::SharedMemory> shared_memory(
+        MakeSharedMemory(kDataBuffer1));
+    base::SharedMemoryHandle new_handle;
+    ASSERT_TRUE(shared_memory->ShareReadOnlyToProcess(0, &new_handle));
+    IPC::Message* message =
+        new TestSharedMemoryHandleMsg1(100, new_handle, 200);
+    sender()->Send(message);
+  }
+
+  base::MessageLoop::current()->Run();
+  CommonTearDown();
+}
+
+void ShareReadOnlyToProcessCallback(IPC::Sender* sender,
+                                    const IPC::Message& message) {
+  base::SharedMemoryHandle shm(GetSharedMemoryHandleFromMsg1(message));
+
+  // Try to map the memory as writable.
+  scoped_ptr<base::SharedMemory> shared_memory(
+      MapSharedMemoryHandle(shm, false));
+  ASSERT_EQ(nullptr, shared_memory->memory());
+
+  // Now try as read-only.
+  scoped_ptr<base::SharedMemory> shared_memory2(
+      MapSharedMemoryHandle(shm.Duplicate(), true));
+  int current_prot, max_prot;
+  ASSERT_TRUE(IPC::GetMachProtections(shared_memory2->memory(),
+                                      shared_memory2->mapped_size(),
+                                      &current_prot, &max_prot));
+  ASSERT_EQ(VM_PROT_READ, current_prot);
+  ASSERT_EQ(VM_PROT_READ, max_prot);
+
+  bool success =
+      memcmp(shared_memory2->memory(), kDataBuffer1, strlen(kDataBuffer1)) == 0;
+  SendControlMessage(sender, success);
+}
+
+MULTIPROCESS_IPC_TEST_CLIENT_MAIN(ShareReadOnlyToProcess) {
+  return CommonPrivilegedProcessMain(&ShareReadOnlyToProcessCallback,
+                                     "ShareReadOnlyToProcess");
+}
+
 }  // namespace