chrome_frame/chrome_frame_helper_main.cc - chromium/src - Git at Google

 // Copyright (c) 2011 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.
 //
 // chrome_frame_helper_main.cc : The .exe that bootstraps the
 // chrome_frame_helper.dll.
 //
 // This is a small exe that loads the hook dll to set the event hooks and then
 // waits in a message loop. It is intended to be shut down by looking for a
 // window with the class and title
 // kChromeFrameHelperWindowClassName and kChromeFrameHelperWindowName and then
 // sending that window a WM_CLOSE message.
 //

 #include <crtdbg.h>
 #include <objbase.h>
 #include <stdlib.h>
 #include <windows.h>

 #include "chrome_frame/chrome_frame_helper_util.h"
 #include "chrome_frame/crash_server_init.h"
 #include "chrome_frame/registry_watcher.h"

 namespace {

 // Window class and window names.
 const wchar_t kChromeFrameHelperWindowClassName[] =
     L"ChromeFrameHelperWindowClass";
 const wchar_t kChromeFrameHelperWindowName[] =
     L"ChromeFrameHelperWindowName";

 const wchar_t kChromeFrameClientStateKey[] =
     L"Software\\Google\\Update\\ClientState\\"
     L"{8BA986DA-5100-405E-AA35-86F34A02ACBF}";
 const wchar_t kChromeFrameUninstallCmdExeValue[] = L"UninstallString";
 const wchar_t kChromeFrameUninstallCmdArgsValue[] = L"UninstallArguments";

 const wchar_t kBHORegistrationPath[] =
     L"SOFTWARE\\Microsoft\\Windows\\CurrentVersion\\Explorer"
     L"\\Browser Helper Objects";

 const wchar_t kStartupArg[] = L"--startup";
 const wchar_t kForceUninstall[] = L"--force-uninstall";

 HWND g_hwnd = NULL;
 const UINT kRegistryWatcherChangeMessage = WM_USER + 42;

 }  // namespace

 // Small helper class that assists in loading the DLL that contains code
 // to register our event hook callback. Automatically removes the hook and
 // unloads the DLL on destruction.
 class HookDllLoader {
  public:
   HookDllLoader() : dll_(NULL), start_proc_(NULL), stop_proc_(NULL) {}
   ~HookDllLoader() {
     if (dll_) {
       Unload();
     }
   }

   bool Load() {
     dll_ = LoadLibrary(L"chrome_frame_helper.dll");
     if (dll_) {
       start_proc_ = GetProcAddress(dll_, "StartUserModeBrowserInjection");
       stop_proc_ = GetProcAddress(dll_, "StopUserModeBrowserInjection");
     }

     bool result = true;
     if (!start_proc_ || !stop_proc_) {
       _ASSERTE(L"failed to load hook dll.");
       result = false;
     } else {
       if (FAILED(start_proc_())) {
         _ASSERTE(L"failed to initialize hook dll.");
         result = false;
       }
     }
     return result;
   }

   void Unload() {
     if (stop_proc_) {
       stop_proc_();
     }
     if (dll_) {
       FreeLibrary(dll_);
     }
   }

  private:
   HMODULE dll_;
   PROC start_proc_;
   PROC stop_proc_;
 };

 // Checks the window title and then class of hwnd. If they match with that
 // of a chrome_frame_helper.exe window, then add it to the list of windows
 // pointed to by lparam.
 BOOL CALLBACK CloseHelperWindowsEnumProc(HWND hwnd, LPARAM lparam) {
   _ASSERTE(lparam != 0);

   wchar_t title_buffer[MAX_PATH] = {0};
   if (GetWindowText(hwnd, title_buffer, MAX_PATH)) {
     if (lstrcmpiW(title_buffer, kChromeFrameHelperWindowName) == 0) {
       wchar_t class_buffer[MAX_PATH] = {0};
       if (GetClassName(hwnd, class_buffer, MAX_PATH)) {
         if (lstrcmpiW(class_buffer, kChromeFrameHelperWindowClassName) == 0) {
           if (hwnd != reinterpret_cast<HWND>(lparam)) {
             PostMessage(hwnd, WM_CLOSE, 0, 0);
           }
         }
       }
     }
   }

   return TRUE;
 }

 // Enumerates all top level windows, looking for those that look like a
 // Chrome Frame helper window. It then closes all of them except for
 // except_me.
 void CloseAllHelperWindowsApartFrom(HWND except_me) {
   EnumWindows(CloseHelperWindowsEnumProc, reinterpret_cast<LPARAM>(except_me));
 }

 LRESULT CALLBACK ChromeFrameHelperWndProc(HWND hwnd,
                                           UINT message,
                                           WPARAM wparam,
                                           LPARAM lparam) {
   switch (message) {
     case WM_CREATE:
       CloseAllHelperWindowsApartFrom(hwnd);
       break;
     case kRegistryWatcherChangeMessage:
       // A system level Chrome appeared. Fall through:
     case WM_DESTROY:
       PostQuitMessage(0);
       break;
     default:
       return ::DefWindowProc(hwnd, message, wparam, lparam);
   }
   return 0;
 }

 HWND RegisterAndCreateWindow(HINSTANCE hinstance) {
   WNDCLASSEX wcex = {0};
   wcex.cbSize         = sizeof(WNDCLASSEX);
   wcex.lpfnWndProc    = ChromeFrameHelperWndProc;
   wcex.hInstance      = GetModuleHandle(NULL);
   wcex.hbrBackground  = reinterpret_cast<HBRUSH>(COLOR_WINDOW+1);
   wcex.lpszClassName  = kChromeFrameHelperWindowClassName;
   RegisterClassEx(&wcex);

   HWND hwnd = CreateWindow(kChromeFrameHelperWindowClassName,
       kChromeFrameHelperWindowName, WS_OVERLAPPEDWINDOW, CW_USEDEFAULT, 0,
       CW_USEDEFAULT, 0, NULL, NULL, hinstance, NULL);

   return hwnd;
 }


 // This method runs the user-level Chrome Frame uninstall command. This is
 // intended to allow it to delegate to an existing system-level install.
 bool UninstallUserLevelChromeFrame() {
   bool success = false;
   HKEY reg_handle = NULL;
   wchar_t reg_path_buffer[MAX_PATH] = {0};
   LONG result = RegOpenKeyEx(HKEY_CURRENT_USER,
                              kChromeFrameClientStateKey,
                              0,
                              KEY_QUERY_VALUE,
                              &reg_handle);
   if (result == ERROR_SUCCESS) {
     wchar_t exe_buffer[MAX_PATH] = {0};
     wchar_t args_buffer[MAX_PATH] = {0};
     LONG exe_result = ReadValue(reg_handle,
                                 kChromeFrameUninstallCmdExeValue,
                                 MAX_PATH,
                                 exe_buffer);
     LONG args_result = ReadValue(reg_handle,
                                  kChromeFrameUninstallCmdArgsValue,
                                  MAX_PATH,
                                  args_buffer);
     RegCloseKey(reg_handle);
     reg_handle = NULL;

     if (exe_result == ERROR_SUCCESS && args_result == ERROR_SUCCESS) {
       STARTUPINFO startup_info = {0};
       startup_info.cb = sizeof(startup_info);
       startup_info.dwFlags = STARTF_USESHOWWINDOW;
       startup_info.wShowWindow = SW_SHOW;
       PROCESS_INFORMATION process_info = {0};

       // Quote the command string in the args.
       wchar_t argument_string[MAX_PATH * 3] = {0};
       int arg_len = _snwprintf(argument_string,
                                _countof(argument_string) - 1,
                                L"\"%s\" %s %s",
                                exe_buffer,
                                args_buffer,
                                kForceUninstall);

       if (arg_len > 0 && CreateProcess(exe_buffer, argument_string,
                                        NULL, NULL, FALSE, 0, NULL, NULL,
                                        &startup_info, &process_info)) {
         // Close handles.
         CloseHandle(process_info.hThread);
         CloseHandle(process_info.hProcess);
         success = true;
       }
     }
   }

   return success;
 }

 void WaitCallback() {
   // Check if the Chrome Frame BHO is now in the list of registered BHOs:
   if (IsBHOLoadingPolicyRegistered()) {
     PostMessage(g_hwnd, kRegistryWatcherChangeMessage, 0, 0);
   }
 }

 int APIENTRY wWinMain(HINSTANCE hinstance, HINSTANCE, wchar_t*, int show_cmd) {
   google_breakpad::scoped_ptr<google_breakpad::ExceptionHandler> breakpad(
     InitializeCrashReporting(NORMAL));

   if (IsSystemLevelChromeFrameInstalled()) {
     // If we're running at startup, check for system-level Chrome Frame
     // installations. If we have one, time
     // to bail, also schedule user-level CF to be uninstalled at next logon.
     const wchar_t* cmd_line = ::GetCommandLine();
     if (cmd_line && wcsstr(cmd_line, kStartupArg) != NULL) {
       bool uninstalled = UninstallUserLevelChromeFrame();
       _ASSERTE(uninstalled);
     }
     return 0;
   }

   // Create a window with a known class and title just to listen for WM_CLOSE
   // messages that will shut us down.
   g_hwnd = RegisterAndCreateWindow(hinstance);
   _ASSERTE(IsWindow(g_hwnd));

   // Load the hook dll, and set the event hooks.
   HookDllLoader loader;
   bool loaded = loader.Load();
   _ASSERTE(loaded);

   // Start up the registry watcher
   RegistryWatcher registry_watcher(HKEY_LOCAL_MACHINE, kBHORegistrationPath,
                                    WaitCallback);
   bool watching = registry_watcher.StartWatching();
   _ASSERTE(watching);

   if (loaded) {
     MSG msg;
     BOOL ret;
     // Main message loop:
     while ((ret = GetMessage(&msg, NULL, 0, 0))) {
       if (ret == -1) {
         break;
       } else {
         TranslateMessage(&msg);
         DispatchMessage(&msg);
       }
     }
   }

   UnregisterClass(kChromeFrameHelperWindowClassName, hinstance);
   return 0;
 }
	// Copyright (c) 2011 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.
	//
	// chrome_frame_helper_main.cc : The .exe that bootstraps the
	// chrome_frame_helper.dll.
	//
	// This is a small exe that loads the hook dll to set the event hooks and then
	// waits in a message loop. It is intended to be shut down by looking for a
	// window with the class and title
	// kChromeFrameHelperWindowClassName and kChromeFrameHelperWindowName and then
	// sending that window a WM_CLOSE message.
	//

	#include <crtdbg.h>
	#include <objbase.h>
	#include <stdlib.h>
	#include <windows.h>

	#include "chrome_frame/chrome_frame_helper_util.h"
	#include "chrome_frame/crash_server_init.h"
	#include "chrome_frame/registry_watcher.h"

	namespace {

	// Window class and window names.
	const wchar_t kChromeFrameHelperWindowClassName[] =
	L"ChromeFrameHelperWindowClass";
	const wchar_t kChromeFrameHelperWindowName[] =
	L"ChromeFrameHelperWindowName";

	const wchar_t kChromeFrameClientStateKey[] =
	L"Software\\Google\\Update\\ClientState\\"
	L"{8BA986DA-5100-405E-AA35-86F34A02ACBF}";
	const wchar_t kChromeFrameUninstallCmdExeValue[] = L"UninstallString";
	const wchar_t kChromeFrameUninstallCmdArgsValue[] = L"UninstallArguments";

	const wchar_t kBHORegistrationPath[] =
	L"SOFTWARE\\Microsoft\\Windows\\CurrentVersion\\Explorer"
	L"\\Browser Helper Objects";

	const wchar_t kStartupArg[] = L"--startup";
	const wchar_t kForceUninstall[] = L"--force-uninstall";

	HWND g_hwnd = NULL;
	const UINT kRegistryWatcherChangeMessage = WM_USER + 42;

	} // namespace

	// Small helper class that assists in loading the DLL that contains code
	// to register our event hook callback. Automatically removes the hook and
	// unloads the DLL on destruction.
	class HookDllLoader {
	public:
	HookDllLoader() : dll_(NULL), start_proc_(NULL), stop_proc_(NULL) {}
	~HookDllLoader() {
	if (dll_) {
	Unload();
	}
	}

	bool Load() {
	dll_ = LoadLibrary(L"chrome_frame_helper.dll");
	if (dll_) {
	start_proc_ = GetProcAddress(dll_, "StartUserModeBrowserInjection");
	stop_proc_ = GetProcAddress(dll_, "StopUserModeBrowserInjection");
	}

	bool result = true;
	if (!start_proc_ \|\| !stop_proc_) {
	_ASSERTE(L"failed to load hook dll.");
	result = false;
	} else {
	if (FAILED(start_proc_())) {
	_ASSERTE(L"failed to initialize hook dll.");
	result = false;
	}
	}
	return result;
	}

	void Unload() {
	if (stop_proc_) {
	stop_proc_();
	}
	if (dll_) {
	FreeLibrary(dll_);
	}
	}

	private:
	HMODULE dll_;
	PROC start_proc_;
	PROC stop_proc_;
	};

	// Checks the window title and then class of hwnd. If they match with that
	// of a chrome_frame_helper.exe window, then add it to the list of windows
	// pointed to by lparam.
	BOOL CALLBACK CloseHelperWindowsEnumProc(HWND hwnd, LPARAM lparam) {
	_ASSERTE(lparam != 0);

	wchar_t title_buffer[MAX_PATH] = {0};
	if (GetWindowText(hwnd, title_buffer, MAX_PATH)) {
	if (lstrcmpiW(title_buffer, kChromeFrameHelperWindowName) == 0) {
	wchar_t class_buffer[MAX_PATH] = {0};
	if (GetClassName(hwnd, class_buffer, MAX_PATH)) {
	if (lstrcmpiW(class_buffer, kChromeFrameHelperWindowClassName) == 0) {
	if (hwnd != reinterpret_cast<HWND>(lparam)) {
	PostMessage(hwnd, WM_CLOSE, 0, 0);
	}
	}
	}
	}
	}

	return TRUE;
	}

	// Enumerates all top level windows, looking for those that look like a
	// Chrome Frame helper window. It then closes all of them except for
	// except_me.
	void CloseAllHelperWindowsApartFrom(HWND except_me) {
	EnumWindows(CloseHelperWindowsEnumProc, reinterpret_cast<LPARAM>(except_me));
	}

	LRESULT CALLBACK ChromeFrameHelperWndProc(HWND hwnd,
	UINT message,
	WPARAM wparam,
	LPARAM lparam) {
	switch (message) {
	case WM_CREATE:
	CloseAllHelperWindowsApartFrom(hwnd);
	break;
	case kRegistryWatcherChangeMessage:
	// A system level Chrome appeared. Fall through:
	case WM_DESTROY:
	PostQuitMessage(0);
	break;
	default:
	return ::DefWindowProc(hwnd, message, wparam, lparam);
	}
	return 0;
	}

	HWND RegisterAndCreateWindow(HINSTANCE hinstance) {
	WNDCLASSEX wcex = {0};
	wcex.cbSize = sizeof(WNDCLASSEX);
	wcex.lpfnWndProc = ChromeFrameHelperWndProc;
	wcex.hInstance = GetModuleHandle(NULL);
	wcex.hbrBackground = reinterpret_cast<HBRUSH>(COLOR_WINDOW+1);
	wcex.lpszClassName = kChromeFrameHelperWindowClassName;
	RegisterClassEx(&wcex);

	HWND hwnd = CreateWindow(kChromeFrameHelperWindowClassName,
	kChromeFrameHelperWindowName, WS_OVERLAPPEDWINDOW, CW_USEDEFAULT, 0,
	CW_USEDEFAULT, 0, NULL, NULL, hinstance, NULL);

	return hwnd;
	}


	// This method runs the user-level Chrome Frame uninstall command. This is
	// intended to allow it to delegate to an existing system-level install.
	bool UninstallUserLevelChromeFrame() {
	bool success = false;
	HKEY reg_handle = NULL;
	wchar_t reg_path_buffer[MAX_PATH] = {0};
	LONG result = RegOpenKeyEx(HKEY_CURRENT_USER,
	kChromeFrameClientStateKey,
	0,
	KEY_QUERY_VALUE,
	&reg_handle);
	if (result == ERROR_SUCCESS) {
	wchar_t exe_buffer[MAX_PATH] = {0};
	wchar_t args_buffer[MAX_PATH] = {0};
	LONG exe_result = ReadValue(reg_handle,
	kChromeFrameUninstallCmdExeValue,
	MAX_PATH,
	exe_buffer);
	LONG args_result = ReadValue(reg_handle,
	kChromeFrameUninstallCmdArgsValue,
	MAX_PATH,
	args_buffer);
	RegCloseKey(reg_handle);
	reg_handle = NULL;

	if (exe_result == ERROR_SUCCESS && args_result == ERROR_SUCCESS) {
	STARTUPINFO startup_info = {0};
	startup_info.cb = sizeof(startup_info);
	startup_info.dwFlags = STARTF_USESHOWWINDOW;
	startup_info.wShowWindow = SW_SHOW;
	PROCESS_INFORMATION process_info = {0};

	// Quote the command string in the args.
	wchar_t argument_string[MAX_PATH * 3] = {0};
	int arg_len = _snwprintf(argument_string,
	_countof(argument_string) - 1,
	L"\"%s\" %s %s",
	exe_buffer,
	args_buffer,
	kForceUninstall);

	if (arg_len > 0 && CreateProcess(exe_buffer, argument_string,
	NULL, NULL, FALSE, 0, NULL, NULL,
	&startup_info, &process_info)) {
	// Close handles.
	CloseHandle(process_info.hThread);
	CloseHandle(process_info.hProcess);
	success = true;
	}
	}
	}

	return success;
	}

	void WaitCallback() {
	// Check if the Chrome Frame BHO is now in the list of registered BHOs:
	if (IsBHOLoadingPolicyRegistered()) {
	PostMessage(g_hwnd, kRegistryWatcherChangeMessage, 0, 0);
	}
	}

	int APIENTRY wWinMain(HINSTANCE hinstance, HINSTANCE, wchar_t*, int show_cmd) {
	google_breakpad::scoped_ptr<google_breakpad::ExceptionHandler> breakpad(
	InitializeCrashReporting(NORMAL));

	if (IsSystemLevelChromeFrameInstalled()) {
	// If we're running at startup, check for system-level Chrome Frame
	// installations. If we have one, time
	// to bail, also schedule user-level CF to be uninstalled at next logon.
	const wchar_t* cmd_line = ::GetCommandLine();
	if (cmd_line && wcsstr(cmd_line, kStartupArg) != NULL) {
	bool uninstalled = UninstallUserLevelChromeFrame();
	_ASSERTE(uninstalled);
	}
	return 0;
	}

	// Create a window with a known class and title just to listen for WM_CLOSE
	// messages that will shut us down.
	g_hwnd = RegisterAndCreateWindow(hinstance);
	_ASSERTE(IsWindow(g_hwnd));

	// Load the hook dll, and set the event hooks.
	HookDllLoader loader;
	bool loaded = loader.Load();
	_ASSERTE(loaded);

	// Start up the registry watcher
	RegistryWatcher registry_watcher(HKEY_LOCAL_MACHINE, kBHORegistrationPath,
	WaitCallback);
	bool watching = registry_watcher.StartWatching();
	_ASSERTE(watching);

	if (loaded) {
	MSG msg;
	BOOL ret;
	// Main message loop:
	while ((ret = GetMessage(&msg, NULL, 0, 0))) {
	if (ret == -1) {
	break;
	} else {
	TranslateMessage(&msg);
	DispatchMessage(&msg);
	}
	}
	}

	UnregisterClass(kChromeFrameHelperWindowClassName, hinstance);
	return 0;
	}