[chrome_elf] Big ELF cleanup. Part 1.

chrome_elf/hook_util/test/hook_util_test.cc

Index: chrome_elf/hook_util/test/hook_util_test.cc
diff --git a/chrome_elf/hook_util/test/hook_util_test.cc b/chrome_elf/hook_util/test/hook_util_test.cc
new file mode 100644
index 0000000000000000000000000000000000000000..ee2609c998ff0d361655584b25f30734849bd45f
--- /dev/null
+++ b/chrome_elf/hook_util/test/hook_util_test.cc
@@ -0,0 +1,103 @@
+// Copyright 2016 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 <windows.h>
+
+#include "chrome_elf/hook_util/hook_util.h"
+// Compile in this test DLL, so that it's in the IAT.
+#include "chrome_elf/hook_util/test/hook_util_test_dll.h"
+#include "testing/gtest/include/gtest/gtest.h"
+
+namespace {
+
+// IATHook test constants.
+const char kIATTestDllName[] = "hook_util_test_dll.dll";
+const char kIATExportedApiFunction[] = "ExportedApi";
+
+// IATHook function, which does nothing.
+void IATHookedExportedApi() {
+  return;
+}
+
+// Shady third-party IATHook function, which also does nothing, but different
+// chunk of code/address.
+void IATHookedExportedApiTwo() {
+  printf("Something to make this function different!\n");
+  return;
+}
+
+class HookTest : public testing::Test {
+ protected:
+  HookTest() {}
+};
+
+//------------------------------------------------------------------------------
+// IATHook tests
+//------------------------------------------------------------------------------
+
+TEST_F(HookTest, IATHook) {
+  // Sanity test with no hook.
+  ASSERT_EQ(0, ExportedApiCallCount());
+  ExportedApi();
+  ExportedApi();
+  ASSERT_EQ(2, ExportedApiCallCount());
+
+  // Apply IAT hook.
+  elf_hook::IATHook iat_hook;
+  if (iat_hook.Hook(::GetModuleHandle(nullptr), kIATTestDllName,
+                    kIATExportedApiFunction,
+                    IATHookedExportedApi) != NO_ERROR) {
+    ADD_FAILURE();
+    return;
+  }
+
+  // Make sure hooking twice with the same object fails.
+  if (iat_hook.Hook(::GetModuleHandle(nullptr), kIATTestDllName,
+                    kIATExportedApiFunction,
+                    IATHookedExportedApi) != ERROR_SHARING_VIOLATION)
+    ADD_FAILURE();
+
+  // Call count should not change with hook.
+  ExportedApi();
+  ExportedApi();
+  ExportedApi();
+  EXPECT_EQ(2, ExportedApiCallCount());
+
+  // Remove hook.
+  if (iat_hook.Unhook() != NO_ERROR)
+    ADD_FAILURE();
+
+  // Sanity test things are back to normal.
+  ExportedApi();
+  EXPECT_EQ(3, ExportedApiCallCount());
+
+  // Double unhook should fail.
+  if (iat_hook.Unhook() != ERROR_INVALID_PARAMETER)
+    ADD_FAILURE();
+
+  // Try hooking a non-existent function.
+  if (iat_hook.Hook(::GetModuleHandle(nullptr), kIATTestDllName, "FooBarred",
+                    IATHookedExportedApi) != ERROR_PROC_NOT_FOUND)
+    ADD_FAILURE();
+
+  // Test the case where someone else hooks our hook!  Unhook() should leave it.
+  if (iat_hook.Hook(::GetModuleHandle(nullptr), kIATTestDllName,
+                    kIATExportedApiFunction,
+                    IATHookedExportedApi) != NO_ERROR) {
+    ADD_FAILURE();
+    return;
+  }
+  elf_hook::IATHook shady_third_party_iat_hook;
+  if (shady_third_party_iat_hook.Hook(::GetModuleHandle(nullptr),
+                                      kIATTestDllName, kIATExportedApiFunction,
+                                      IATHookedExportedApiTwo) != NO_ERROR)
+    ADD_FAILURE();
+  if (iat_hook.Unhook() != ERROR_INVALID_FUNCTION)
+    ADD_FAILURE();
+  if (shady_third_party_iat_hook.Unhook() != NO_ERROR)
+    ADD_FAILURE();
+  // NOTE: the first hook was left in and couldn't be cleaned up.
+}
+
+}  // namespace