Make chrome_elf use thunks instead of function pointers.

chrome_elf/create_file/chrome_create_file_unittest.cc

 // Copyright 2014 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_elf/create_file/chrome_create_file.h"
 
 #include <windows.h>
 
 #include <bitset>
 #include <string>
 
 #include "base/base_paths_win.h"
 #include "base/file_util.h"
 #include "base/files/file_path.h"
 #include "base/files/scoped_temp_dir.h"
 #include "base/path_service.h"
 #include "base/threading/platform_thread.h"
 #include "base/win/iat_patch_function.h"
 #include "base/win/scoped_handle.h"
 #include "base/win/windows_version.h"
 #include "chrome_elf/chrome_elf_constants.h"
 #include "chrome_elf/ntdll_cache.h"
+#include "sandbox/win/src/interception_internal.h"
 #include "sandbox/win/src/nt_internals.h"
 #include "testing/gtest/include/gtest/gtest.h"
 #include "testing/platform_test.h"
 
 
 namespace {
 
 // Test fixtures -------------------------------------------------------------
 
 class ChromeCreateFileTest : public PlatformTest {
@@ skipping 47 matching lines @@
     InitCache();
     PlatformTest::SetUp();
 
     base::FilePath user_data_dir;
     PathService::Get(base::DIR_LOCAL_APP_DATA, &user_data_dir);
     ASSERT_TRUE(temp_dir_.CreateUniqueTempDirUnderPath(user_data_dir));
     ASSERT_TRUE(temp_dir2_.CreateUniqueTempDir());
     self_ = this;
   }
 
+  void UnsetThunkStorage() {
+    DWORD old_protect = 0;
+    EXPECT_TRUE(::VirtualProtect(&g_nt_thunk_storage,
+                                 sizeof(g_nt_thunk_storage),
+                                 PAGE_EXECUTE_READWRITE,
+                                 &old_protect));
+    memset(&g_nt_thunk_storage, 0, sizeof(g_nt_thunk_storage));
+
+    EXPECT_TRUE(::VirtualProtect(&g_nt_thunk_storage,
+                                 sizeof(g_nt_thunk_storage),
+                                 PAGE_EXECUTE_READ,
+                                 &old_protect));
+  }
+
   void RedirectNtCreateFileCalls() {
+    UnsetThunkStorage();
     old_func_ptr_ =
         reinterpret_cast<NtCreateFileFunction>(g_ntdll_lookup["NtCreateFile"]);
 
     // KernelBase.dll only exists for Win7 and later, prior to that, kernel32
     // imports from ntdll directly.
     if (base::win::GetVersion() < base::win::VERSION_WIN7) {
       patcher_.Patch(L"kernel32.dll", "ntdll.dll", "NtCreateFile",
           reinterpret_cast<void(*)()>(&FakeNtCreateFile<KERNEL>));
     } else {
       patcher_.Patch(L"kernelbase.dll", "ntdll.dll", "NtCreateFile",
@@ skipping 268 matching lines @@
   // Don't redirect if file is not in UserData directory.
   EXPECT_FALSE(ShouldBypass(desktop_junk_path.value().c_str()));
   EXPECT_FALSE(ShouldBypass(desktop_prefs_path.value().c_str()));
 
   // Only redirect "Preferences" and "Local State" files.
   EXPECT_TRUE(ShouldBypass(local_prefs_path.value().c_str()));
   EXPECT_TRUE(ShouldBypass(local_state_path.value().c_str()));
   EXPECT_FALSE(ShouldBypass(local_junk_path.value().c_str()));
 }
 
-TEST_F(ChromeCreateFileTest, NtCreateFileAddressCheck) {
-  HMODULE ntdll_handle = ::GetModuleHandle(L"ntdll.dll");
-  EXPECT_EQ(::GetProcAddress(ntdll_handle, "NtCreateFile"),
-            g_ntdll_lookup["NtCreateFile"]);
-}
-
 TEST_F(ChromeCreateFileTest, ReadWriteFromNtDll) {
+  UnsetThunkStorage();
   base::FilePath file_name = temp_dir_.path().Append(L"some_file.txt");
   DoWriteCheck(file_name, FILE_ATTRIBUTE_NORMAL, false);
   DoReadCheck(file_name, FILE_ATTRIBUTE_NORMAL, false);
+}
+
+TEST_F(ChromeCreateFileTest, ReadWriteFromThunk) {
+  base::FilePath file_name = temp_dir_.path().Append(L"some_file.txt");
+  DoWriteCheck(file_name, FILE_ATTRIBUTE_NORMAL, false);
+  DoReadCheck(file_name, FILE_ATTRIBUTE_NORMAL, false);
 }
 
 }  // namespace