1 // Copyright 2011 The Chromium Authors
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
5 #include "chrome/app/chrome_exe_main_win.h"
17 #include "base/at_exit.h"
18 #include "base/base_switches.h"
19 #include "base/command_line.h"
20 #include "base/containers/cxx20_erase.h"
21 #include "base/debug/alias.h"
22 #include "base/debug/handle_hooks_win.h"
23 #include "base/feature_list.h"
24 #include "base/files/file_path.h"
25 #include "base/files/file_util.h"
26 #include "base/logging.h"
27 #include "base/path_service.h"
28 #include "base/process/memory.h"
29 #include "base/process/process.h"
30 #include "base/strings/string_number_conversions.h"
31 #include "base/strings/string_split.h"
32 #include "base/strings/string_util.h"
33 #include "base/strings/utf_string_conversions.h"
34 #include "base/time/time.h"
35 #include "base/win/current_module.h"
36 #include "base/win/registry.h"
37 #include "base/win/win_util.h"
38 #include "base/win/windows_version.h"
39 #include "build/build_config.h"
40 #include "chrome/app/delay_load_failure_hook_win.h"
41 #include "chrome/app/exit_code_watcher_win.h"
42 #include "chrome/app/main_dll_loader_win.h"
43 #include "chrome/app/packed_resources_integrity.h"
44 #include "chrome/browser/policy/policy_path_parser.h"
45 #include "chrome/browser/win/chrome_process_finder.h"
46 #include "chrome/chrome_elf/chrome_elf_main.h"
47 #include "chrome/common/chrome_paths_internal.h"
48 #include "chrome/common/chrome_switches.h"
49 #include "chrome/install_static/initialize_from_primary_module.h"
50 #include "chrome/install_static/install_util.h"
51 #include "chrome/install_static/user_data_dir.h"
52 #include "components/crash/core/app/crash_switches.h"
53 #include "components/crash/core/app/crashpad.h"
54 #include "components/crash/core/app/fallback_crash_handling_win.h"
55 #include "components/crash/core/app/run_as_crashpad_handler_win.h"
56 #include "content/public/common/content_switches.h"
57 #include "content/public/common/result_codes.h"
58 #include "third_party/crashpad/crashpad/util/win/initial_client_data.h"
60 #if defined(WIN_CONSOLE_APP)
61 // Forward declaration of main.
67 // Sets the current working directory for the process to the directory holding
68 // the executable if this is the browser process. This avoids leaking a handle
69 // to an arbitrary directory to child processes (e.g., the crashpad handler
70 // process) created before MainDllLoader changes the current working directory
71 // to the browser's version directory.
72 void SetCwdForBrowserProcess() {
73 if (!::IsBrowserProcess())
76 std::array<wchar_t, MAX_PATH + 1> buffer;
78 DWORD length = ::GetModuleFileName(nullptr, &buffer[0], buffer.size());
79 if (!length || length >= buffer.size())
82 base::SetCurrentDirectory(
83 base::FilePath(base::FilePath::StringPieceType(&buffer[0], length))
87 bool IsFastStartSwitch(const std::string& command_line_switch) {
88 return command_line_switch == switches::kProfileDirectory;
91 bool ContainsNonFastStartFlag(const base::CommandLine& command_line) {
92 const base::CommandLine::SwitchMap& switches = command_line.GetSwitches();
93 if (switches.size() > 1)
95 for (base::CommandLine::SwitchMap::const_iterator it = switches.begin();
96 it != switches.end(); ++it) {
97 if (!IsFastStartSwitch(it->first))
103 bool AttemptFastNotify(const base::CommandLine& command_line) {
104 if (ContainsNonFastStartFlag(command_line))
107 base::FilePath user_data_dir;
108 if (!chrome::GetDefaultUserDataDirectory(&user_data_dir))
110 policy::path_parser::CheckUserDataDirPolicy(&user_data_dir);
112 HWND chrome = chrome::FindRunningChromeWindow(user_data_dir);
115 return chrome::AttemptToNotifyRunningChrome(chrome) == chrome::NOTIFY_SUCCESS;
118 // Returns true if |command_line| contains a /prefetch:# argument where # is in
120 bool HasValidWindowsPrefetchArgument(const base::CommandLine& command_line) {
121 const wchar_t kPrefetchArgumentPrefix[] = L"/prefetch:";
123 for (const auto& arg : command_line.argv()) {
124 if (arg.size() == std::size(kPrefetchArgumentPrefix) &&
125 base::StartsWith(arg, kPrefetchArgumentPrefix,
126 base::CompareCase::SENSITIVE)) {
127 return arg[std::size(kPrefetchArgumentPrefix) - 1] >= L'1' &&
128 arg[std::size(kPrefetchArgumentPrefix) - 1] <= L'8';
134 // Some users are getting stuck in compatibility mode. Try to help them escape.
135 // See http://crbug.com/581499. Returns true if a compatibility mode entry was
137 bool RemoveAppCompatFlagsEntry() {
138 base::FilePath current_exe;
139 if (!base::PathService::Get(base::FILE_EXE, ¤t_exe))
141 if (!current_exe.IsAbsolute())
143 base::win::RegKey key;
144 if (key.Open(HKEY_CURRENT_USER,
145 L"Software\\Microsoft\\Windows "
146 L"NT\\CurrentVersion\\AppCompatFlags\\Layers",
147 KEY_READ | KEY_WRITE) == ERROR_SUCCESS) {
149 if (key.ReadValue(current_exe.value().c_str(), &layers) == ERROR_SUCCESS) {
150 std::vector<std::wstring> tokens = base::SplitString(
151 layers, L" ", base::TRIM_WHITESPACE, base::SPLIT_WANT_NONEMPTY);
152 size_t initial_size = tokens.size();
153 static const wchar_t* const kCompatModeTokens[] = {
154 L"WIN95", L"WIN98", L"WIN4SP5", L"WIN2000", L"WINXPSP2",
155 L"WINXPSP3", L"VISTARTM", L"VISTASP1", L"VISTASP2", L"WIN7RTM",
156 L"WINSRV03SP1", L"WINSRV08SP1", L"WIN8RTM",
158 for (const wchar_t* compat_mode_token : kCompatModeTokens) {
159 base::Erase(tokens, compat_mode_token);
162 if (tokens.empty()) {
163 result = key.DeleteValue(current_exe.value().c_str());
165 std::wstring without_compat_mode_tokens =
166 base::JoinString(tokens, L" ");
167 result = key.WriteValue(current_exe.value().c_str(),
168 without_compat_mode_tokens.c_str());
171 // Return if we changed anything so that we can restart.
172 return tokens.size() != initial_size && result == ERROR_SUCCESS;
178 int RunFallbackCrashHandler(const base::CommandLine& cmd_line) {
179 // Retrieve the product & version details we need to report the crash
181 wchar_t exe_file[MAX_PATH] = {};
182 CHECK(::GetModuleFileName(nullptr, exe_file, std::size(exe_file)));
184 std::wstring product_name, version, channel_name, special_build;
185 install_static::GetExecutableVersionDetails(exe_file, &product_name, &version,
186 &special_build, &channel_name);
188 return crash_reporter::RunAsFallbackCrashHandler(
189 cmd_line, base::WideToUTF8(product_name), base::WideToUTF8(version),
190 base::WideToUTF8(channel_name));
193 // In 32-bit builds, the main thread starts with the default (small) stack size.
194 // The ARCH_CPU_32_BITS blocks here and below are in support of moving the main
195 // thread to a fiber with a larger stack size.
196 #if defined(ARCH_CPU_32_BITS)
197 // The information needed to transfer control to the large-stack fiber and later
198 // pass the main routine's exit code back to the small-stack fiber prior to
202 LPVOID original_fiber;
206 // A PFIBER_START_ROUTINE function run on a large-stack fiber that calls the
207 // main routine, stores its return value, and returns control to the small-stack
208 // fiber. |params| must be a pointer to a FiberState struct.
209 void WINAPI FiberBinder(void* params) {
210 auto* fiber_state = static_cast<FiberState*>(params);
211 // Call the main routine from the fiber. Reusing the entry point minimizes
212 // confusion when examining call stacks in crash reports - seeing wWinMain on
213 // the stack is a handy hint that this is the main thread of the process.
214 #if !defined(WIN_CONSOLE_APP)
215 fiber_state->fiber_result =
216 wWinMain(fiber_state->instance, nullptr, nullptr, 0);
217 #else // !defined(WIN_CONSOLE_APP)
218 fiber_state->fiber_result = main();
219 #endif // !defined(WIN_CONSOLE_APP)
220 // Switch back to the main thread to exit.
221 ::SwitchToFiber(fiber_state->original_fiber);
223 #endif // defined(ARCH_CPU_32_BITS)
227 __declspec(dllexport) __cdecl void GetPakFileHashes(
228 const uint8_t** resources_pak,
229 const uint8_t** chrome_100_pak,
230 const uint8_t** chrome_200_pak) {
231 *resources_pak = kSha256_resources_pak.data();
232 *chrome_100_pak = kSha256_chrome_100_percent_pak.data();
233 *chrome_200_pak = kSha256_chrome_200_percent_pak.data();
236 #if !defined(WIN_CONSOLE_APP)
237 int APIENTRY wWinMain(HINSTANCE instance, HINSTANCE prev, wchar_t*, int) {
238 #else // !defined(WIN_CONSOLE_APP)
240 HINSTANCE instance = GetModuleHandle(nullptr);
241 #endif // !defined(WIN_CONSOLE_APP)
243 #if defined(ARCH_CPU_32_BITS)
244 enum class FiberStatus { kConvertFailed, kCreateFiberFailed, kSuccess };
245 FiberStatus fiber_status = FiberStatus::kSuccess;
246 // GetLastError result if fiber conversion failed.
247 DWORD fiber_error = ERROR_SUCCESS;
248 if (!::IsThreadAFiber()) {
249 // Make the main thread's stack size 4 MiB so that it has roughly the same
250 // effective size as the 64-bit build's 8 MiB stack.
251 constexpr size_t kStackSize = 4 * 1024 * 1024; // 4 MiB
252 // Leak the fiber on exit.
253 LPVOID original_fiber =
254 ::ConvertThreadToFiberEx(nullptr, FIBER_FLAG_FLOAT_SWITCH);
255 if (original_fiber) {
256 FiberState fiber_state = {instance, original_fiber};
257 // Create a fiber with a bigger stack and switch to it. Leak the fiber on
259 LPVOID big_stack_fiber = ::CreateFiberEx(
260 0, kStackSize, FIBER_FLAG_FLOAT_SWITCH, FiberBinder, &fiber_state);
261 if (big_stack_fiber) {
262 ::SwitchToFiber(big_stack_fiber);
263 // The fibers must be cleaned up to avoid obscure TLS-related shutdown
265 ::DeleteFiber(big_stack_fiber);
266 ::ConvertFiberToThread();
267 // Control returns here after Chrome has finished running on FiberMain.
268 return fiber_state.fiber_result;
270 fiber_status = FiberStatus::kCreateFiberFailed;
272 fiber_status = FiberStatus::kConvertFailed;
274 // If we reach here then creating and switching to a fiber has failed. This
275 // probably means we are low on memory and will soon crash. Try to report
276 // this error once crash reporting is initialized.
277 fiber_error = ::GetLastError();
278 base::debug::Alias(&fiber_error);
280 // If we are already a fiber then continue normal execution.
281 #endif // defined(ARCH_CPU_32_BITS)
283 SetCwdForBrowserProcess();
284 install_static::InitializeFromPrimaryModule();
285 SignalInitializeCrashReporting();
286 if (IsBrowserProcess())
287 chrome::DisableDelayLoadFailureHooksForMainExecutable();
288 #if defined(ARCH_CPU_32_BITS)
289 // Intentionally crash if converting to a fiber failed.
290 CHECK_EQ(fiber_status, FiberStatus::kSuccess);
291 #endif // defined(ARCH_CPU_32_BITS)
293 // Done here to ensure that OOMs that happen early in process initialization
294 // are correctly signaled to the OS.
295 base::EnableTerminationOnOutOfMemory();
297 // Initialize the CommandLine singleton from the environment.
298 base::CommandLine::Init(0, nullptr);
299 const base::CommandLine* command_line =
300 base::CommandLine::ForCurrentProcess();
302 const std::string process_type =
303 command_line->GetSwitchValueASCII(switches::kProcessType);
305 #if !defined(COMPONENT_BUILD) && DCHECK_IS_ON()
306 // In non-component mode, chrome.exe contains its own base::FeatureList
307 // instance pointer, which remains nullptr. Attempts to access feature state
308 // from chrome.exe should fail, instead of silently returning a default state.
309 base::FeatureList::FailOnFeatureAccessWithoutFeatureList();
311 // Patch the main EXE on non-component builds when DCHECKs are enabled.
312 // This allows detection of third party code that might attempt to meddle with
313 // Chrome's handles. This must be done when single-threaded to avoid other
314 // threads attempting to make calls through the hooks while they are being
316 // Note: The DLL is patched separately, in chrome/app/chrome_main.cc.
317 base::debug::HandleHooks::AddIATPatch(CURRENT_MODULE());
318 #endif // !defined(COMPONENT_BUILD) && DCHECK_IS_ON()
320 // Confirm that an explicit prefetch profile is used for all process types
321 // except for the browser process. Any new process type will have to assign
322 // itself a prefetch id. See kPrefetchArgument* constants in
323 // content_switches.cc for details.
324 DCHECK(process_type.empty() ||
325 HasValidWindowsPrefetchArgument(*command_line));
327 if (process_type == crash_reporter::switches::kCrashpadHandler) {
328 // Check if we should monitor the exit code of this process
329 std::unique_ptr<ExitCodeWatcher> exit_code_watcher;
331 crash_reporter::SetupFallbackCrashHandling(*command_line);
332 // no-periodic-tasks is specified for self monitoring crashpad instances.
333 // This is to ensure we are a crashpad process monitoring the browser
334 // process and not another crashpad process.
335 if (!command_line->HasSwitch("no-periodic-tasks")) {
336 // Retrieve the client process from the command line
337 crashpad::InitialClientData initial_client_data;
338 if (initial_client_data.InitializeFromString(
339 command_line->GetSwitchValueASCII("initial-client-data"))) {
340 // Setup exit code watcher to monitor the parent process
341 HANDLE duplicate_handle = INVALID_HANDLE_VALUE;
343 ::GetCurrentProcess(), initial_client_data.client_process(),
344 ::GetCurrentProcess(), &duplicate_handle,
345 PROCESS_QUERY_INFORMATION, FALSE, DUPLICATE_SAME_ACCESS)) {
346 base::Process parent_process(duplicate_handle);
347 exit_code_watcher = std::make_unique<ExitCodeWatcher>();
348 if (exit_code_watcher->Initialize(std::move(parent_process))) {
349 exit_code_watcher->StartWatching();
355 // The handler process must always be passed the user data dir on the
357 DCHECK(command_line->HasSwitch(switches::kUserDataDir));
359 base::FilePath user_data_dir =
360 command_line->GetSwitchValuePath(switches::kUserDataDir);
361 int crashpad_status = crash_reporter::RunAsCrashpadHandler(
362 *base::CommandLine::ForCurrentProcess(), user_data_dir,
363 switches::kProcessType, switches::kUserDataDir);
364 if (crashpad_status != 0 && exit_code_watcher) {
365 // Crashpad failed to initialize, explicitly stop the exit code watcher
366 // so the crashpad-handler process can exit with an error
367 exit_code_watcher->StopWatching();
369 return crashpad_status;
370 } else if (process_type == crash_reporter::switches::kFallbackCrashHandler) {
371 return RunFallbackCrashHandler(*command_line);
374 const base::TimeTicks exe_entry_point_ticks = base::TimeTicks::Now();
376 // Signal Chrome Elf that Chrome has begun to start.
379 // The exit manager is in charge of calling the dtors of singletons.
380 base::AtExitManager exit_manager;
382 if (AttemptFastNotify(*command_line))
385 RemoveAppCompatFlagsEntry();
387 // Load and launch the chrome dll. *Everything* happens inside.
388 VLOG(1) << "About to load main DLL.";
389 MainDllLoader* loader = MakeMainDllLoader();
390 int rc = loader->Launch(instance, exe_entry_point_ticks);
391 loader->RelaunchChromeBrowserWithNewCommandLineIfNeeded();
394 // Process shutdown is hard and some process types have been crashing during
395 // shutdown. TerminateCurrentProcessImmediately is safer and faster.
396 if (process_type == switches::kUtilityProcess ||
397 process_type == switches::kPpapiPluginProcess) {
398 base::Process::TerminateCurrentProcessImmediately(rc);