chrome_elf/blacklist/test/blacklist_test.cc

   1 // Copyright 2013 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "base/environment.h"
   6 #include "base/files/file_path.h"
   7 #include "base/files/scoped_temp_dir.h"
   8 #include "base/i18n/case_conversion.h"
   9 #include "base/path_service.h"
  10 #include "base/scoped_native_library.h"
  11 #include "base/strings/string16.h"
  12 #include "base/strings/string_number_conversions.h"
  13 #include "base/strings/utf_string_conversions.h"
  14 #include "base/test/test_reg_util_win.h"
  15 #include "base/win/registry.h"
  16 #include "chrome_elf/blacklist/blacklist.h"
  17 #include "chrome_elf/blacklist/test/blacklist_test_main_dll.h"
  18 #include "chrome_elf/chrome_elf_constants.h"
  19 #include "testing/gtest/include/gtest/gtest.h"
  20 #include "version.h"  // NOLINT
  21
  22 const wchar_t kTestDllName1[] = L"blacklist_test_dll_1.dll";
  23 const wchar_t kTestDllName2[] = L"blacklist_test_dll_2.dll";
  24 const wchar_t kTestDllName3[] = L"blacklist_test_dll_3.dll";
  25
  26 const wchar_t kDll2Beacon[] = L"{F70A0100-2889-4629-9B44-610FE5C73231}";
  27 const wchar_t kDll3Beacon[] = L"{9E056AEC-169E-400c-B2D0-5A07E3ACE2EB}";
  28
  29 extern const wchar_t* kEnvVars[];
  30
  31 extern "C" {
  32 // When modifying the blacklist in the test process, use the exported test dll
  33 // functions on the test blacklist dll, not the ones linked into the test
  34 // executable itself.
  35 __declspec(dllimport) void TestDll_AddDllsFromRegistryToBlacklist();
  36 __declspec(dllimport) bool TestDll_AddDllToBlacklist(const wchar_t* dll_name);
  37 __declspec(dllimport) int TestDll_BlacklistSize();
  38 __declspec(dllimport) void TestDll_BlockedDll(size_t blocked_index);
  39 __declspec(dllimport) int TestDll_GetBlacklistIndex(const wchar_t* dll_name);
  40 __declspec(dllimport) bool TestDll_IsBlacklistInitialized();
  41 __declspec(dllimport) bool TestDll_RemoveDllFromBlacklist(
  42     const wchar_t* dll_name);
  43 __declspec(dllimport) bool TestDll_SuccessfullyBlocked(
  44     const wchar_t** blocked_dlls,
  45     int* size);
  46 }
  47
  48 namespace {
  49
  50 struct TestData {
  51   const wchar_t* dll_name;
  52   const wchar_t* dll_beacon;
  53 } test_data[] = {
  54     {kTestDllName2, kDll2Beacon},
  55     {kTestDllName3, kDll3Beacon}
  56 };
  57
  58 class BlacklistTest : public testing::Test {
  59  protected:
  60   BlacklistTest() : override_manager_(), num_initially_blocked_(0) {
  61     override_manager_.OverrideRegistry(HKEY_CURRENT_USER);
  62   }
  63
  64   void CheckBlacklistedDllsNotLoaded() {
  65     base::FilePath current_dir;
  66     ASSERT_TRUE(PathService::Get(base::DIR_EXE, &current_dir));
  67
  68     for (int i = 0; i < arraysize(test_data); ++i) {
  69       // Ensure that the dll has not been loaded both by inspecting the handle
  70       // returned by LoadLibrary and by looking for an environment variable that
  71       // is set when the DLL's entry point is called.
  72       base::ScopedNativeLibrary dll_blacklisted(
  73           current_dir.Append(test_data[i].dll_name));
  74       EXPECT_FALSE(dll_blacklisted.is_valid());
  75       EXPECT_EQ(0u, ::GetEnvironmentVariable(test_data[i].dll_beacon, NULL, 0));
  76       dll_blacklisted.Reset(NULL);
  77
  78       // Ensure that the dll is recorded as blocked.
  79       int array_size = 1 + num_initially_blocked_;
  80       std::vector<const wchar_t*> blocked_dlls(array_size);
  81       TestDll_SuccessfullyBlocked(&blocked_dlls[0], &array_size);
  82       EXPECT_EQ(1 + num_initially_blocked_, array_size);
  83       EXPECT_STREQ(test_data[i].dll_name, blocked_dlls[num_initially_blocked_]);
  84
  85       // Remove the DLL from the blacklist. Ensure that it loads and that its
  86       // entry point was called.
  87       EXPECT_TRUE(TestDll_RemoveDllFromBlacklist(test_data[i].dll_name));
  88       base::ScopedNativeLibrary dll(current_dir.Append(test_data[i].dll_name));
  89       EXPECT_TRUE(dll.is_valid());
  90       EXPECT_NE(0u, ::GetEnvironmentVariable(test_data[i].dll_beacon, NULL, 0));
  91       dll.Reset(NULL);
  92
  93       ::SetEnvironmentVariable(test_data[i].dll_beacon, NULL);
  94
  95       // Ensure that the dll won't load even if the name has different
  96       // capitalization.
  97       base::string16 uppercase_name =
  98           base::i18n::ToUpper(test_data[i].dll_name);
  99       EXPECT_TRUE(TestDll_AddDllToBlacklist(uppercase_name.c_str()));
 100       base::ScopedNativeLibrary dll_blacklisted_different_case(
 101           current_dir.Append(test_data[i].dll_name));
 102       EXPECT_FALSE(dll_blacklisted_different_case.is_valid());
 103       EXPECT_EQ(0u, ::GetEnvironmentVariable(test_data[i].dll_beacon, NULL, 0));
 104       dll_blacklisted_different_case.Reset(NULL);
 105
 106       EXPECT_TRUE(TestDll_RemoveDllFromBlacklist(uppercase_name.c_str()));
 107
 108       // The blocked dll was removed, so the number of blocked dlls should
 109       // return to what it originally was.
 110       int num_blocked_dlls = 0;
 111       TestDll_SuccessfullyBlocked(NULL, &num_blocked_dlls);
 112       EXPECT_EQ(num_initially_blocked_, num_blocked_dlls);
 113     }
 114   }
 115
 116   scoped_ptr<base::win::RegKey> blacklist_registry_key_;
 117   registry_util::RegistryOverrideManager override_manager_;
 118
 119   // The number of dlls initially blocked by the blacklist.
 120   int num_initially_blocked_;
 121
 122  private:
 123   void SetUp() override {
 124     // Force an import from blacklist_test_main_dll.
 125     InitBlacklistTestDll();
 126     blacklist_registry_key_.reset(
 127         new base::win::RegKey(HKEY_CURRENT_USER,
 128                               blacklist::kRegistryBeaconPath,
 129                               KEY_QUERY_VALUE | KEY_SET_VALUE));
 130
 131     // Find out how many dlls were blocked before the test starts.
 132     TestDll_SuccessfullyBlocked(NULL, &num_initially_blocked_);
 133   }
 134
 135   void TearDown() override {
 136     TestDll_RemoveDllFromBlacklist(kTestDllName1);
 137     TestDll_RemoveDllFromBlacklist(kTestDllName2);
 138     TestDll_RemoveDllFromBlacklist(kTestDllName3);
 139   }
 140 };
 141
 142 TEST_F(BlacklistTest, Beacon) {
 143   // Ensure that the beacon state starts off 'running' for this version.
 144   LONG result = blacklist_registry_key_->WriteValue(
 145       blacklist::kBeaconState, blacklist::BLACKLIST_SETUP_RUNNING);
 146   EXPECT_EQ(ERROR_SUCCESS, result);
 147
 148   result = blacklist_registry_key_->WriteValue(blacklist::kBeaconVersion,
 149                                                TEXT(CHROME_VERSION_STRING));
 150   EXPECT_EQ(ERROR_SUCCESS, result);
 151
 152   // First call should find the beacon and reset it.
 153   EXPECT_TRUE(blacklist::ResetBeacon());
 154
 155   // First call should succeed as the beacon is enabled.
 156   EXPECT_TRUE(blacklist::LeaveSetupBeacon());
 157 }
 158
 159 TEST_F(BlacklistTest, AddAndRemoveModules) {
 160   EXPECT_TRUE(TestDll_AddDllToBlacklist(L"foo.dll"));
 161   // Adding the same item twice should be idempotent.
 162   EXPECT_TRUE(TestDll_AddDllToBlacklist(L"foo.dll"));
 163   EXPECT_TRUE(TestDll_RemoveDllFromBlacklist(L"foo.dll"));
 164   EXPECT_FALSE(TestDll_RemoveDllFromBlacklist(L"foo.dll"));
 165
 166   // Increase the blacklist size by 1 to include the NULL pointer
 167   // that marks the end.
 168   int empty_spaces =
 169       blacklist::kTroublesomeDllsMaxCount - (TestDll_BlacklistSize() + 1);
 170   std::vector<base::string16> added_dlls;
 171   added_dlls.reserve(empty_spaces);
 172   for (int i = 0; i < empty_spaces; ++i) {
 173     added_dlls.push_back(base::IntToString16(i) + L".dll");
 174     EXPECT_TRUE(TestDll_AddDllToBlacklist(added_dlls[i].c_str())) << i;
 175   }
 176   EXPECT_FALSE(TestDll_AddDllToBlacklist(L"overflow.dll"));
 177   for (int i = 0; i < empty_spaces; ++i) {
 178     EXPECT_TRUE(TestDll_RemoveDllFromBlacklist(added_dlls[i].c_str())) << i;
 179   }
 180   EXPECT_FALSE(TestDll_RemoveDllFromBlacklist(added_dlls[0].c_str()));
 181   EXPECT_FALSE(
 182       TestDll_RemoveDllFromBlacklist(added_dlls[empty_spaces - 1].c_str()));
 183 }
 184
 185 TEST_F(BlacklistTest, SuccessfullyBlocked) {
 186   // Add 5 news dlls to blacklist.
 187   const int kDesiredBlacklistSize = 1;
 188   std::vector<base::string16> dlls_to_block;
 189   for (int i = 0; i < kDesiredBlacklistSize; ++i) {
 190     dlls_to_block.push_back(base::IntToString16(i) + L".dll");
 191     ASSERT_TRUE(TestDll_AddDllToBlacklist(dlls_to_block[i].c_str()));
 192   }
 193
 194   // Block the dlls, one at a time, and ensure SuccesfullyBlocked correctly
 195   // passes the list of blocked dlls.
 196   for (int i = 0; i < kDesiredBlacklistSize; ++i) {
 197     TestDll_BlockedDll(TestDll_GetBlacklistIndex(dlls_to_block[i].c_str()));
 198
 199     int size = 0;
 200     TestDll_SuccessfullyBlocked(NULL, &size);
 201     ASSERT_EQ(num_initially_blocked_ + i + 1, size);
 202
 203     std::vector<const wchar_t*> blocked_dlls(size);
 204     TestDll_SuccessfullyBlocked(&(blocked_dlls[0]), &size);
 205     ASSERT_EQ(num_initially_blocked_ + i + 1, size);
 206
 207     for (int j = 0; j <= i; ++j) {
 208       EXPECT_STREQ(blocked_dlls[num_initially_blocked_ + j],
 209                    dlls_to_block[j].c_str());
 210     }
 211   }
 212
 213   // Remove the dlls from the blacklist now that we are done.
 214   for (const auto& dll : dlls_to_block) {
 215     EXPECT_TRUE(TestDll_RemoveDllFromBlacklist(dll.c_str()));
 216   }
 217 }
 218
 219 TEST_F(BlacklistTest, LoadBlacklistedLibrary) {
 220   base::FilePath current_dir;
 221   ASSERT_TRUE(PathService::Get(base::DIR_EXE, &current_dir));
 222
 223   // Ensure that the blacklist is loaded.
 224   ASSERT_TRUE(TestDll_IsBlacklistInitialized());
 225
 226   // Test that an un-blacklisted DLL can load correctly.
 227   base::ScopedNativeLibrary dll1(current_dir.Append(kTestDllName1));
 228   EXPECT_TRUE(dll1.is_valid());
 229   dll1.Reset(NULL);
 230
 231   int num_blocked_dlls = 0;
 232   TestDll_SuccessfullyBlocked(NULL, &num_blocked_dlls);
 233   EXPECT_EQ(num_initially_blocked_, num_blocked_dlls);
 234
 235   // Add all DLLs to the blacklist then check they are blocked.
 236   for (int i = 0; i < arraysize(test_data); ++i) {
 237     EXPECT_TRUE(TestDll_AddDllToBlacklist(test_data[i].dll_name));
 238   }
 239   CheckBlacklistedDllsNotLoaded();
 240 }
 241
 242 TEST_F(BlacklistTest, AddDllsFromRegistryToBlacklist) {
 243   // Ensure that the blacklist is loaded.
 244   ASSERT_TRUE(TestDll_IsBlacklistInitialized());
 245
 246   // Delete the finch registry key to clear its values.
 247   base::win::RegKey key(HKEY_CURRENT_USER,
 248                         blacklist::kRegistryFinchListPath,
 249                         KEY_QUERY_VALUE | KEY_SET_VALUE);
 250   key.DeleteKey(L"");
 251
 252   // Add the test dlls to the registry (with their name as both key and value).
 253   base::win::RegKey finch_blacklist_registry_key(
 254       HKEY_CURRENT_USER,
 255       blacklist::kRegistryFinchListPath,
 256       KEY_QUERY_VALUE | KEY_SET_VALUE);
 257   for (int i = 0; i < arraysize(test_data); ++i) {
 258     finch_blacklist_registry_key.WriteValue(test_data[i].dll_name,
 259                                             test_data[i].dll_name);
 260   }
 261
 262   TestDll_AddDllsFromRegistryToBlacklist();
 263   CheckBlacklistedDllsNotLoaded();
 264 }
 265
 266 void TestResetBeacon(scoped_ptr<base::win::RegKey>& key,
 267                      DWORD input_state,
 268                      DWORD expected_output_state) {
 269   LONG result = key->WriteValue(blacklist::kBeaconState, input_state);
 270   EXPECT_EQ(ERROR_SUCCESS, result);
 271
 272   EXPECT_TRUE(blacklist::ResetBeacon());
 273   DWORD blacklist_state = blacklist::BLACKLIST_STATE_MAX;
 274   result = key->ReadValueDW(blacklist::kBeaconState, &blacklist_state);
 275   EXPECT_EQ(ERROR_SUCCESS, result);
 276   EXPECT_EQ(expected_output_state, blacklist_state);
 277 }
 278
 279 TEST_F(BlacklistTest, ResetBeacon) {
 280   // Ensure that ResetBeacon resets properly on successful runs and not on
 281   // failed or disabled runs.
 282   TestResetBeacon(blacklist_registry_key_,
 283                   blacklist::BLACKLIST_SETUP_RUNNING,
 284                   blacklist::BLACKLIST_ENABLED);
 285
 286   TestResetBeacon(blacklist_registry_key_,
 287                   blacklist::BLACKLIST_SETUP_FAILED,
 288                   blacklist::BLACKLIST_SETUP_FAILED);
 289
 290   TestResetBeacon(blacklist_registry_key_,
 291                   blacklist::BLACKLIST_DISABLED,
 292                   blacklist::BLACKLIST_DISABLED);
 293 }
 294
 295 TEST_F(BlacklistTest, SetupFailed) {
 296   // Ensure that when the number of failed tries reaches the maximum allowed,
 297   // the blacklist state is set to failed.
 298   LONG result = blacklist_registry_key_->WriteValue(
 299       blacklist::kBeaconState, blacklist::BLACKLIST_SETUP_RUNNING);
 300   EXPECT_EQ(ERROR_SUCCESS, result);
 301
 302   // Set the attempt count so that on the next failure the blacklist is
 303   // disabled.
 304   result = blacklist_registry_key_->WriteValue(
 305       blacklist::kBeaconAttemptCount, blacklist::kBeaconMaxAttempts - 1);
 306   EXPECT_EQ(ERROR_SUCCESS, result);
 307
 308   EXPECT_FALSE(blacklist::LeaveSetupBeacon());
 309
 310   DWORD attempt_count = 0;
 311   blacklist_registry_key_->ReadValueDW(blacklist::kBeaconAttemptCount,
 312                                        &attempt_count);
 313   EXPECT_EQ(attempt_count, blacklist::kBeaconMaxAttempts);
 314
 315   DWORD blacklist_state = blacklist::BLACKLIST_STATE_MAX;
 316   result = blacklist_registry_key_->ReadValueDW(blacklist::kBeaconState,
 317                                                 &blacklist_state);
 318   EXPECT_EQ(ERROR_SUCCESS, result);
 319   EXPECT_EQ(blacklist_state, blacklist::BLACKLIST_SETUP_FAILED);
 320 }
 321
 322 TEST_F(BlacklistTest, SetupSucceeded) {
 323   // Starting with the enabled beacon should result in the setup running state
 324   // and the attempt counter reset to zero.
 325   LONG result = blacklist_registry_key_->WriteValue(
 326       blacklist::kBeaconState, blacklist::BLACKLIST_ENABLED);
 327   EXPECT_EQ(ERROR_SUCCESS, result);
 328   result = blacklist_registry_key_->WriteValue(blacklist::kBeaconAttemptCount,
 329                                                blacklist::kBeaconMaxAttempts);
 330   EXPECT_EQ(ERROR_SUCCESS, result);
 331
 332   EXPECT_TRUE(blacklist::LeaveSetupBeacon());
 333
 334   DWORD blacklist_state = blacklist::BLACKLIST_STATE_MAX;
 335   blacklist_registry_key_->ReadValueDW(blacklist::kBeaconState,
 336                                        &blacklist_state);
 337   EXPECT_EQ(blacklist_state, blacklist::BLACKLIST_SETUP_RUNNING);
 338
 339   DWORD attempt_count = blacklist::kBeaconMaxAttempts;
 340   blacklist_registry_key_->ReadValueDW(blacklist::kBeaconAttemptCount,
 341                                        &attempt_count);
 342   EXPECT_EQ(static_cast<DWORD>(0), attempt_count);
 343 }
 344
 345 }  // namespace