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      1 // Copyright (c) 2012 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 // chrome_tab.cc : Implementation of DLL Exports.
      6 
      7 // Need to include this before the ATL headers below.
      8 #include "chrome_frame/chrome_tab.h"
      9 
     10 #include <atlsecurity.h>
     11 #include <objbase.h>
     12 
     13 #include "base/at_exit.h"
     14 #include "base/basictypes.h"
     15 #include "base/command_line.h"
     16 #include "base/file_util.h"
     17 #include "base/file_version_info.h"
     18 #include "base/logging.h"
     19 #include "base/logging_win.h"
     20 #include "base/path_service.h"
     21 #include "base/process/launch.h"
     22 #include "base/strings/string16.h"
     23 #include "base/strings/string_number_conversions.h"
     24 #include "base/strings/string_piece.h"
     25 #include "base/strings/string_util.h"
     26 #include "base/strings/sys_string_conversions.h"
     27 #include "base/strings/utf_string_conversions.h"
     28 #include "base/win/registry.h"
     29 #include "base/win/windows_version.h"
     30 #include "chrome/common/chrome_constants.h"
     31 #include "chrome/common/chrome_switches.h"
     32 #include "chrome/common/metrics/entropy_provider.h"
     33 #include "chrome/installer/util/google_update_settings.h"
     34 #include "chrome_frame/bho.h"
     35 #include "chrome_frame/chrome_active_document.h"
     36 #include "chrome_frame/chrome_frame_activex.h"
     37 #include "chrome_frame/chrome_frame_automation.h"
     38 #include "chrome_frame/chrome_frame_reporting.h"
     39 #include "chrome_frame/chrome_launcher_utils.h"
     40 #include "chrome_frame/chrome_protocol.h"
     41 #include "chrome_frame/dll_redirector.h"
     42 #include "chrome_frame/exception_barrier.h"
     43 #include "chrome_frame/pin_module.h"
     44 #include "chrome_frame/resource.h"
     45 #include "chrome_frame/utils.h"
     46 #include "grit/chrome_frame_resources.h"
     47 #include "url/url_util.h"
     48 
     49 using base::win::RegKey;
     50 
     51 namespace {
     52 
     53 const wchar_t kInternetSettings[] =
     54     L"Software\\Microsoft\\Windows\\CurrentVersion\\Internet Settings";
     55 
     56 const wchar_t kProtocolHandlers[] =
     57     L"Software\\Classes\\Protocols\\Handler";
     58 
     59 const wchar_t kRunOnce[] =
     60     L"Software\\Microsoft\\Windows\\CurrentVersion\\RunOnce";
     61 
     62 const wchar_t kRunKeyName[] = L"ChromeFrameHelper";
     63 
     64 const wchar_t kChromeFrameHelperExe[] = L"chrome_frame_helper.exe";
     65 const wchar_t kChromeFrameHelperStartupArg[] = L"--startup";
     66 
     67 // Window class and window names.
     68 // TODO(robertshield): These and other constants need to be refactored into
     69 // a common chrome_frame_constants.h|cc and built into a separate lib
     70 // (either chrome_frame_utils or make another one).
     71 const wchar_t kChromeFrameHelperWindowClassName[] =
     72     L"ChromeFrameHelperWindowClass";
     73 const wchar_t kChromeFrameHelperWindowName[] =
     74     L"ChromeFrameHelperWindowName";
     75 
     76 // {0562BFC3-2550-45b4-BD8E-A310583D3A6F}
     77 const GUID kChromeFrameProvider =
     78     { 0x562bfc3, 0x2550, 0x45b4,
     79         { 0xbd, 0x8e, 0xa3, 0x10, 0x58, 0x3d, 0x3a, 0x6f } };
     80 
     81 const wchar_t kPostPlatformUAKey[] =
     82     L"Software\\Microsoft\\Windows\\CurrentVersion\\Internet Settings\\"
     83     L"User Agent\\Post Platform";
     84 const wchar_t kChromeFramePrefix[] = L"chromeframe/";
     85 
     86 // See comments in DllGetClassObject.
     87 LPFNGETCLASSOBJECT g_dll_get_class_object_redir_ptr = NULL;
     88 
     89 // This function has the side effect of initializing an unprotected
     90 // vector pointer inside GoogleUrl. If this is called during DLL loading,
     91 // it has the effect of avoiding an initialization race on that pointer.
     92 // TODO(siggi): fix GoogleUrl.
     93 void InitGoogleUrl() {
     94   static const char kDummyUrl[] = "http://www.google.com";
     95 
     96   url_util::IsStandard(kDummyUrl,
     97                        url_parse::MakeRange(0, arraysize(kDummyUrl)));
     98 }
     99 
    100 class ChromeTabModule : public CAtlDllModuleT<ChromeTabModule> {
    101  public:
    102   typedef CAtlDllModuleT<ChromeTabModule> ParentClass;
    103 
    104   ChromeTabModule() : do_system_registration_(true), crash_reporting_(NULL) {}
    105 
    106   DECLARE_LIBID(LIBID_ChromeTabLib)
    107   DECLARE_REGISTRY_APPID_RESOURCEID(IDR_CHROMETAB,
    108                                     "{FD9B1B31-F4D8-436A-8F4F-D3C2E36733D3}")
    109 
    110   // Override to add our SYSTIME binary value to registry scripts.
    111   // See chrome_frame_activex.rgs for usage.
    112   virtual HRESULT AddCommonRGSReplacements(IRegistrarBase* registrar) throw() {
    113     HRESULT hr = ParentClass::AddCommonRGSReplacements(registrar);
    114 
    115     if (SUCCEEDED(hr)) {
    116       SYSTEMTIME local_time;
    117       ::GetSystemTime(&local_time);
    118       std::string hex(base::HexEncode(&local_time, sizeof(local_time)));
    119       base::StringPiece sp_hex(hex);
    120       hr = registrar->AddReplacement(L"SYSTIME",
    121                                      base::SysNativeMBToWide(sp_hex).c_str());
    122       DCHECK(SUCCEEDED(hr));
    123     }
    124 
    125     if (SUCCEEDED(hr)) {
    126       base::FilePath app_path =
    127           chrome_launcher::GetChromeExecutablePath().DirName();
    128       hr = registrar->AddReplacement(L"CHROME_APPPATH",
    129                                      app_path.value().c_str());
    130       DCHECK(SUCCEEDED(hr));
    131     }
    132 
    133     if (SUCCEEDED(hr)) {
    134       hr = registrar->AddReplacement(L"CHROME_APPNAME",
    135                                      chrome::kBrowserProcessExecutableName);
    136       DCHECK(SUCCEEDED(hr));
    137 
    138       // Fill in VERSION from the VERSIONINFO stored in the DLL's resources.
    139       scoped_ptr<FileVersionInfo> module_version_info(
    140           FileVersionInfo::CreateFileVersionInfoForCurrentModule());
    141       DCHECK(module_version_info != NULL);
    142       std::wstring file_version(module_version_info->file_version());
    143       hr = registrar->AddReplacement(L"VERSION", file_version.c_str());
    144       DCHECK(SUCCEEDED(hr));
    145     }
    146 
    147     if (SUCCEEDED(hr)) {
    148       // Add the directory of chrome_launcher.exe.  This will be the same
    149       // as the directory for the current DLL.
    150       std::wstring module_dir;
    151       base::FilePath module_path;
    152       if (PathService::Get(base::FILE_MODULE, &module_path)) {
    153         module_dir = module_path.DirName().value();
    154       } else {
    155         NOTREACHED();
    156       }
    157       hr = registrar->AddReplacement(L"CHROME_LAUNCHER_APPPATH",
    158                                      module_dir.c_str());
    159       DCHECK(SUCCEEDED(hr));
    160     }
    161 
    162     if (SUCCEEDED(hr)) {
    163       // Add the filename of chrome_launcher.exe
    164       hr = registrar->AddReplacement(L"CHROME_LAUNCHER_APPNAME",
    165                                      chrome_launcher::kLauncherExeBaseName);
    166       DCHECK(SUCCEEDED(hr));
    167     }
    168 
    169     if (SUCCEEDED(hr)) {
    170       // Add the registry hive to use.
    171       // Note: This is ugly as hell. I'd rather use the pMapEntries parameter
    172       // to CAtlModule::UpdateRegistryFromResource, unfortunately we have a
    173       // few components that are registered by calling their
    174       // static T::UpdateRegistry() methods directly, which doesn't allow
    175       // pMapEntries to be passed through :-(
    176       if (do_system_registration_) {
    177         hr = registrar->AddReplacement(L"HIVE", L"HKLM");
    178       } else {
    179         hr = registrar->AddReplacement(L"HIVE", L"HKCU");
    180       }
    181       DCHECK(SUCCEEDED(hr));
    182     }
    183 
    184     if (SUCCEEDED(hr)) {
    185       // Add the Chrome Frame CLSID.
    186       wchar_t cf_clsid[64];
    187       StringFromGUID2(CLSID_ChromeFrame, &cf_clsid[0], arraysize(cf_clsid));
    188       hr = registrar->AddReplacement(L"CHROME_FRAME_CLSID", &cf_clsid[0]);
    189     }
    190 
    191     return hr;
    192   }
    193 
    194   // The module is "locked" when an object takes a reference on it. The first
    195   // time it is locked, take a reference on crash reporting to bind its lifetime
    196   // to the module.
    197   virtual LONG Lock() throw() {
    198     LONG result = ParentClass::Lock();
    199     if (result == 1) {
    200       DCHECK_EQ(crash_reporting_,
    201                 static_cast<chrome_frame::ScopedCrashReporting*>(NULL));
    202       crash_reporting_ = new chrome_frame::ScopedCrashReporting();
    203     }
    204     return result;
    205   }
    206 
    207   // The module is "unlocked" when an object that had a reference on it is
    208   // destroyed. The last time it is unlocked, release the reference on crash
    209   // reporting.
    210   virtual LONG Unlock() throw() {
    211     LONG result = ParentClass::Unlock();
    212     if (!result) {
    213       DCHECK_NE(crash_reporting_,
    214                 static_cast<chrome_frame::ScopedCrashReporting*>(NULL));
    215       delete crash_reporting_;
    216       crash_reporting_ = NULL;
    217     }
    218     return result;
    219   }
    220 
    221   // See comments in AddCommonRGSReplacements
    222   bool do_system_registration_;
    223 
    224  private:
    225   // A scoper created when the module is initially locked and destroyed when it
    226   // is finally unlocked. This is not a scoped_ptr since that could cause
    227   // reporting to shut down at exit, which would lead to problems with the
    228   // loader lock.
    229   chrome_frame::ScopedCrashReporting* crash_reporting_;
    230 };
    231 
    232 ChromeTabModule _AtlModule;
    233 
    234 base::AtExitManager* g_exit_manager = NULL;
    235 
    236 HRESULT RefreshElevationPolicy() {
    237   const wchar_t kIEFrameDll[] = L"ieframe.dll";
    238   const char kIERefreshPolicy[] = "IERefreshElevationPolicy";
    239   HRESULT hr = E_NOTIMPL;
    240 
    241   // Stick an SEH in the chain to prevent the VEH from picking up on first
    242   // chance exceptions caused by loading ieframe.dll. Use the vanilla
    243   // ExceptionBarrier to report any exceptions that do make their way to us
    244   // though.
    245   ExceptionBarrier barrier;
    246 
    247   HMODULE ieframe_module = LoadLibrary(kIEFrameDll);
    248   if (ieframe_module) {
    249     typedef HRESULT (__stdcall *IERefreshPolicy)();
    250     IERefreshPolicy ie_refresh_policy = reinterpret_cast<IERefreshPolicy>(
    251         GetProcAddress(ieframe_module, kIERefreshPolicy));
    252 
    253     if (ie_refresh_policy) {
    254       hr = ie_refresh_policy();
    255     } else {
    256       hr = HRESULT_FROM_WIN32(GetLastError());
    257     }
    258 
    259     FreeLibrary(ieframe_module);
    260   } else {
    261     hr = HRESULT_FROM_WIN32(GetLastError());
    262   }
    263 
    264   return hr;
    265 }
    266 
    267 // Experimental boot prefetch optimization for Chrome Frame
    268 //
    269 // If chrome is warmed up during a single reboot, it gets paged
    270 // in for subsequent reboots and the cold startup times essentially
    271 // look like warm times thereafter! The 'warm up' is done by
    272 // setting up a 'RunOnce' key during DLLRegisterServer of
    273 // npchrome_frame.dll.
    274 //
    275 // This works because chrome prefetch becomes part of boot
    276 // prefetch file ntosboot-b00dfaad.pf and paged in on subsequent
    277 // reboots. As long as the sytem does not undergo significant
    278 // memory pressure those pages remain in memory and we get pretty
    279 // amazing startup times, down to about 300 ms from 1200 ms
    280 //
    281 // The downside is:
    282 // - Whether chrome frame is used or not, there's a read penalty
    283 //  (1200-300 =) 900 ms for every boot.
    284 // - Heavy system memory usage after reboot will nullify the benefits
    285 //  but the user will still pay the cost.
    286 // - Overall the time saved will always be less than total time spent
    287 //  paging in chrome
    288 // - We are not sure when the chrome 'warm up' will age out from the
    289 //  boot prefetch file.
    290 //
    291 // The idea here is to try this out on chrome frame dev channel
    292 // and see if it produces a significant drift in startup numbers.
    293 HRESULT SetupRunOnce() {
    294   HRESULT result = E_FAIL;
    295 
    296   string16 channel_name;
    297   if (base::win::GetVersion() < base::win::VERSION_VISTA &&
    298       GoogleUpdateSettings::GetChromeChannelAndModifiers(true, &channel_name)) {
    299     std::transform(channel_name.begin(), channel_name.end(),
    300                    channel_name.begin(), tolower);
    301     // Use this only for the dev channel.
    302     if (channel_name.find(L"dev") != string16::npos) {
    303       HKEY hive = HKEY_CURRENT_USER;
    304       if (IsSystemProcess()) {
    305         // For system installs, our updates will be running as SYSTEM which
    306         // makes writing to a RunOnce key under HKCU not so terribly useful.
    307         hive = HKEY_LOCAL_MACHINE;
    308       }
    309 
    310       RegKey run_once;
    311       LONG ret = run_once.Create(hive, kRunOnce, KEY_READ | KEY_WRITE);
    312       if (ret == ERROR_SUCCESS) {
    313         CommandLine run_once_cmd(chrome_launcher::GetChromeExecutablePath());
    314         run_once_cmd.AppendSwitchASCII(switches::kAutomationClientChannelID,
    315                                        "0");
    316         run_once_cmd.AppendSwitch(switches::kChromeFrame);
    317         ret = run_once.WriteValue(L"A",
    318                                   run_once_cmd.GetCommandLineString().c_str());
    319       }
    320       result = HRESULT_FROM_WIN32(ret);
    321     } else {
    322       result = S_FALSE;
    323     }
    324   } else {
    325     // We're on a non-XP version of Windows or on a stable channel. Nothing
    326     // needs doing.
    327     result = S_FALSE;
    328   }
    329 
    330   return result;
    331 }
    332 
    333 // Helper method called for user-level installs where we don't have admin
    334 // permissions. Starts up the long running process and registers it to get it
    335 // started at next boot.
    336 HRESULT SetupUserLevelHelper() {
    337   HRESULT hr = S_OK;
    338 
    339   // Remove existing run-at-startup entry.
    340   base::win::RemoveCommandFromAutoRun(HKEY_CURRENT_USER, kRunKeyName);
    341 
    342   // Build the chrome_frame_helper command line.
    343   base::FilePath module_path;
    344   base::FilePath helper_path;
    345   if (PathService::Get(base::FILE_MODULE, &module_path)) {
    346     module_path = module_path.DirName();
    347     helper_path = module_path.Append(kChromeFrameHelperExe);
    348     if (!base::PathExists(helper_path)) {
    349       // If we can't find the helper in the current directory, try looking
    350       // one up (this is the layout in the build output folder).
    351       module_path = module_path.DirName();
    352       helper_path = module_path.Append(kChromeFrameHelperExe);
    353       DCHECK(base::PathExists(helper_path)) <<
    354           "Could not find chrome_frame_helper.exe.";
    355     }
    356 
    357     // Find window handle of existing instance.
    358     HWND old_window = FindWindow(kChromeFrameHelperWindowClassName,
    359                                  kChromeFrameHelperWindowName);
    360 
    361     if (base::PathExists(helper_path)) {
    362       std::wstring helper_path_cmd(L"\"");
    363       helper_path_cmd += helper_path.value();
    364       helper_path_cmd += L"\" ";
    365       helper_path_cmd += kChromeFrameHelperStartupArg;
    366 
    367       // Add new run-at-startup entry.
    368       if (!base::win::AddCommandToAutoRun(HKEY_CURRENT_USER, kRunKeyName,
    369                                           helper_path_cmd)) {
    370         hr = E_FAIL;
    371         LOG(ERROR) << "Could not add helper process to auto run key.";
    372       }
    373 
    374       // Start new instance.
    375       base::LaunchOptions options;
    376       options.start_hidden = true;
    377       bool launched = base::LaunchProcess(helper_path.value(), options, NULL);
    378       if (!launched) {
    379         hr = E_FAIL;
    380         PLOG(DFATAL) << "Could not launch helper process.";
    381       }
    382 
    383       // Kill old instance using window handle.
    384       if (IsWindow(old_window)) {
    385         BOOL result = PostMessage(old_window, WM_CLOSE, 0, 0);
    386         if (!result) {
    387           PLOG(ERROR) << "Failed to post close message to old helper process: ";
    388         }
    389       }
    390     } else {
    391       hr = HRESULT_FROM_WIN32(ERROR_FILE_NOT_FOUND);
    392     }
    393   } else {
    394     hr = E_UNEXPECTED;
    395     NOTREACHED();
    396   }
    397 
    398   return hr;
    399 }
    400 
    401 // To delete the user agent, set value to NULL.
    402 // The is_system parameter indicates whether this is a per machine or a per
    403 // user installation.
    404 HRESULT SetChromeFrameUA(bool is_system, const wchar_t* value) {
    405   HRESULT hr = E_FAIL;
    406   HKEY parent_hive = is_system ? HKEY_LOCAL_MACHINE : HKEY_CURRENT_USER;
    407 
    408   RegKey ua_key;
    409   LONG reg_result = ua_key.Create(parent_hive, kPostPlatformUAKey,
    410                                   KEY_READ | KEY_WRITE);
    411   if (reg_result == ERROR_SUCCESS) {
    412     // Make sure that we unregister ChromeFrame UA strings registered previously
    413     wchar_t value_name[MAX_PATH + 1] = {};
    414     wchar_t value_data[MAX_PATH + 1] = {};
    415 
    416     DWORD value_index = 0;
    417     while (value_index < ua_key.GetValueCount()) {
    418       DWORD name_size = arraysize(value_name);
    419       DWORD value_size = arraysize(value_data);
    420       DWORD type = 0;
    421       LRESULT ret = ::RegEnumValue(ua_key.Handle(), value_index, value_name,
    422                                    &name_size, NULL, &type,
    423                                    reinterpret_cast<BYTE*>(value_data),
    424                                    &value_size);
    425       if (ret == ERROR_SUCCESS) {
    426         if (StartsWith(value_name, kChromeFramePrefix, false)) {
    427           ua_key.DeleteValue(value_name);
    428         } else {
    429           ++value_index;
    430         }
    431       } else {
    432         break;
    433       }
    434     }
    435 
    436     std::wstring chrome_frame_ua_value_name = kChromeFramePrefix;
    437     chrome_frame_ua_value_name += GetCurrentModuleVersion();
    438     if (value) {
    439       ua_key.WriteValue(chrome_frame_ua_value_name.c_str(), value);
    440     }
    441     hr = S_OK;
    442   } else {
    443     DLOG(ERROR) << __FUNCTION__ << ": " << kPostPlatformUAKey
    444                 << ", error code = " << reg_result;
    445     hr = HRESULT_FROM_WIN32(reg_result);
    446   }
    447   return hr;
    448 }
    449 
    450 class SecurityDescBackup {
    451  public:
    452   explicit SecurityDescBackup(const std::wstring& backup_key)
    453       : backup_key_name_(backup_key) {}
    454   ~SecurityDescBackup() {}
    455 
    456   // Save given security descriptor to the backup key.
    457   bool SaveSecurity(const CSecurityDesc& sd) {
    458     CString str;
    459     if (!sd.ToString(&str))
    460       return false;
    461 
    462     RegKey backup_key(HKEY_LOCAL_MACHINE, backup_key_name_.c_str(),
    463                       KEY_READ | KEY_WRITE);
    464     if (backup_key.Valid()) {
    465       return backup_key.WriteValue(NULL, str.GetString()) == ERROR_SUCCESS;
    466     }
    467 
    468     return false;
    469   }
    470 
    471   // Restore security descriptor from backup key to given key name.
    472   bool RestoreSecurity(const wchar_t* key_name) {
    473     std::wstring sddl;
    474     if (!ReadBackupKey(&sddl))
    475       return false;
    476 
    477     // Create security descriptor from string.
    478     CSecurityDesc sd;
    479     if (!sd.FromString(sddl.c_str()))
    480       return false;
    481 
    482     bool result = true;
    483     // Restore DACL and Owner of the key from saved security descriptor.
    484     CDacl dacl;
    485     CSid owner;
    486     sd.GetDacl(&dacl);
    487     sd.GetOwner(&owner);
    488 
    489     DWORD error = ::SetNamedSecurityInfo(const_cast<wchar_t*>(key_name),
    490         SE_REGISTRY_KEY, OWNER_SECURITY_INFORMATION | DACL_SECURITY_INFORMATION,
    491         const_cast<SID*>(owner.GetPSID()), NULL,
    492         const_cast<ACL*>(dacl.GetPACL()), NULL);
    493 
    494     DeleteBackupKey();
    495     return (error == ERROR_SUCCESS);
    496   }
    497 
    498  private:
    499   // Read SDDL string from backup key
    500   bool ReadBackupKey(std::wstring* sddl) {
    501     RegKey backup_key(HKEY_LOCAL_MACHINE, backup_key_name_.c_str(), KEY_READ);
    502     if (!backup_key.Valid())
    503       return false;
    504 
    505     DWORD len = 0;
    506     DWORD reg_type = REG_NONE;
    507     if (backup_key.ReadValue(NULL, NULL, &len, &reg_type) != ERROR_SUCCESS)
    508       return false;
    509     DCHECK_EQ(0u, len % sizeof(wchar_t));
    510 
    511     if ((len == 0) || (reg_type != REG_SZ))
    512       return false;
    513 
    514     size_t wchar_count = 1 + len / sizeof(wchar_t);
    515     if (backup_key.ReadValue(NULL, WriteInto(sddl, wchar_count), &len,
    516                              &reg_type) != ERROR_SUCCESS) {
    517       return false;
    518     }
    519 
    520     return true;
    521   }
    522 
    523   void DeleteBackupKey() {
    524     ::RegDeleteKey(HKEY_LOCAL_MACHINE, backup_key_name_.c_str());
    525   }
    526 
    527   std::wstring backup_key_name_;
    528 };
    529 
    530 struct TokenWithPrivileges {
    531   TokenWithPrivileges() {
    532     token_.GetEffectiveToken(TOKEN_ADJUST_PRIVILEGES | TOKEN_QUERY);
    533     token_.GetUser(&user_);
    534   }
    535 
    536   ~TokenWithPrivileges() {
    537     token_.EnableDisablePrivileges(take_ownership_);
    538     token_.EnableDisablePrivileges(restore_);
    539   }
    540 
    541   bool EnablePrivileges() {
    542     if (take_ownership_.GetCount() == 0)
    543       if (!token_.EnablePrivilege(L"SeTakeOwnershipPrivilege",
    544                                   &take_ownership_))
    545         return false;
    546 
    547     if (restore_.GetCount() == 0)
    548       if (!token_.EnablePrivilege(L"SeRestorePrivilege", &restore_))
    549         return false;
    550 
    551     return true;
    552   }
    553 
    554   const CSid& GetUser() const {
    555     return user_;
    556   }
    557 
    558  private:
    559   CAccessToken token_;
    560   CTokenPrivileges take_ownership_;
    561   CTokenPrivileges restore_;
    562   CSid user_;
    563 };
    564 
    565 HRESULT SetOrDeleteMimeHandlerKey(bool set, HKEY root_key) {
    566   std::wstring key_name = kInternetSettings;
    567   key_name.append(L"\\Secure Mime Handlers");
    568   RegKey key(root_key, key_name.c_str(), KEY_READ | KEY_WRITE);
    569   if (!key.Valid())
    570     return false;
    571 
    572   LONG result1 = ERROR_SUCCESS;
    573   LONG result2 = ERROR_SUCCESS;
    574   if (set) {
    575     result1 = key.WriteValue(L"ChromeTab.ChromeActiveDocument", 1);
    576     result2 = key.WriteValue(L"ChromeTab.ChromeActiveDocument.1", 1);
    577   } else {
    578     result1 = key.DeleteValue(L"ChromeTab.ChromeActiveDocument");
    579     result2 = key.DeleteValue(L"ChromeTab.ChromeActiveDocument.1");
    580   }
    581 
    582   return result1 != ERROR_SUCCESS ? HRESULT_FROM_WIN32(result1) :
    583                                     HRESULT_FROM_WIN32(result2);
    584 }
    585 
    586 void OnPinModule() {
    587   // Pin crash reporting by leaking a reference.
    588   ignore_result(new chrome_frame::ScopedCrashReporting());
    589 }
    590 
    591 // Chrome Frame registration functions.
    592 //-----------------------------------------------------------------------------
    593 HRESULT RegisterSecuredMimeHandler(bool enable, bool is_system) {
    594   if (!is_system) {
    595     return SetOrDeleteMimeHandlerKey(enable, HKEY_CURRENT_USER);
    596   } else if (base::win::GetVersion() < base::win::VERSION_VISTA) {
    597     return SetOrDeleteMimeHandlerKey(enable, HKEY_LOCAL_MACHINE);
    598   }
    599 
    600   std::wstring mime_key = kInternetSettings;
    601   mime_key.append(L"\\Secure Mime Handlers");
    602   std::wstring backup_key = kInternetSettings;
    603   backup_key.append(L"\\__backup_SMH__");
    604   std::wstring object_name = L"MACHINE\\";
    605   object_name.append(mime_key);
    606 
    607   TokenWithPrivileges token_;
    608   if (!token_.EnablePrivileges())
    609     return E_ACCESSDENIED;
    610 
    611   // If there is a backup key - something bad happened; try to restore
    612   // security on "Secure Mime Handlers" from the backup.
    613   SecurityDescBackup backup(backup_key);
    614   backup.RestoreSecurity(object_name.c_str());
    615 
    616   // Read old security descriptor of the Mime key first.
    617   CSecurityDesc sd;
    618   if (!AtlGetSecurityDescriptor(object_name.c_str(), SE_REGISTRY_KEY, &sd)) {
    619     return E_FAIL;
    620   }
    621 
    622   backup.SaveSecurity(sd);
    623   HRESULT hr = E_FAIL;
    624   // set new owner
    625   if (AtlSetOwnerSid(object_name.c_str(), SE_REGISTRY_KEY, token_.GetUser())) {
    626     // set new dacl
    627     CDacl new_dacl;
    628     sd.GetDacl(&new_dacl);
    629     new_dacl.AddAllowedAce(token_.GetUser(), GENERIC_WRITE | GENERIC_READ);
    630     if (AtlSetDacl(object_name.c_str(), SE_REGISTRY_KEY, new_dacl)) {
    631       hr = SetOrDeleteMimeHandlerKey(enable, HKEY_LOCAL_MACHINE);
    632     }
    633   }
    634 
    635   backup.RestoreSecurity(object_name.c_str());
    636   return hr;
    637 }
    638 
    639 HRESULT RegisterActiveDoc(bool reg, bool is_system) {
    640   // We have to call the static T::UpdateRegistry function instead of
    641   // _AtlModule.UpdateRegistryFromResourceS(IDR_CHROMEFRAME_ACTIVEDOC, reg)
    642   // because there is specific OLEMISC replacement.
    643   return ChromeActiveDocument::UpdateRegistry(reg);
    644 }
    645 
    646 HRESULT RegisterActiveX(bool reg, bool is_system) {
    647   // We have to call the static T::UpdateRegistry function instead of
    648   // _AtlModule.UpdateRegistryFromResourceS(IDR_CHROMEFRAME_ACTIVEX, reg)
    649   // because there is specific OLEMISC replacement.
    650   return ChromeFrameActivex::UpdateRegistry(reg);
    651 }
    652 
    653 HRESULT RegisterElevationPolicy(bool reg, bool is_system) {
    654   HRESULT hr = S_OK;
    655   if (base::win::GetVersion() >= base::win::VERSION_VISTA) {
    656     // Register the elevation policy. This must succeed for Chrome Frame to
    657     // be able launch Chrome when running in low-integrity IE.
    658     hr = _AtlModule.UpdateRegistryFromResourceS(IDR_CHROMEFRAME_ELEVATION, reg);
    659     if (SUCCEEDED(hr)) {
    660       // Ignore failures since old versions of IE 7 (e.g., 7.0.6000.16386, which
    661       // shipped with Vista RTM) do not export IERefreshElevationPolicy.
    662       RefreshElevationPolicy();
    663     }
    664   }
    665   return hr;
    666 }
    667 
    668 HRESULT RegisterProtocol(bool reg, bool is_system) {
    669   return _AtlModule.UpdateRegistryFromResourceS(IDR_CHROMEPROTOCOL, reg);
    670 }
    671 
    672 HRESULT RegisterBhoClsid(bool reg, bool is_system) {
    673   return Bho::UpdateRegistry(reg);
    674 }
    675 
    676 HRESULT RegisterBhoIE(bool reg, bool is_system) {
    677   if (is_system) {
    678     return _AtlModule.UpdateRegistryFromResourceS(IDR_REGISTER_BHO, reg);
    679   } else {
    680     if (reg) {
    681       // Setup the long running process:
    682       return SetupUserLevelHelper();
    683     } else {
    684       // Unschedule the user-level helper. Note that we don't kill it here
    685       // so that during updates we don't have a time window with no running
    686       // helper. Uninstalls and updates will explicitly kill the helper from
    687       // within the installer. Unregister existing run-at-startup entry.
    688       return base::win::RemoveCommandFromAutoRun(HKEY_CURRENT_USER,
    689                                                  kRunKeyName) ? S_OK : E_FAIL;
    690     }
    691   }
    692 }
    693 
    694 HRESULT RegisterTypeLib(bool reg, bool is_system) {
    695   if (reg && !is_system) {
    696     // Enables the RegisterTypeLib Function function to override default
    697     // registry mappings under Windows Vista Service Pack 1 (SP1),
    698     // Windows Server 2008, and later operating system versions
    699     typedef void (WINAPI* OaEnablePerUserTypeLibReg)(void);
    700     OaEnablePerUserTypeLibReg per_user_typelib_func =
    701         reinterpret_cast<OaEnablePerUserTypeLibReg>(
    702             GetProcAddress(GetModuleHandle(L"oleaut32.dll"),
    703                            "OaEnablePerUserTLibRegistration"));
    704     if (per_user_typelib_func) {
    705       (*per_user_typelib_func)();
    706     }
    707   }
    708   return reg ?
    709       UtilRegisterTypeLib(_AtlComModule.m_hInstTypeLib,
    710                           NULL, !is_system) :
    711       UtilUnRegisterTypeLib(_AtlComModule.m_hInstTypeLib,
    712                             NULL, !is_system);
    713 }
    714 
    715 HRESULT RegisterLegacyNPAPICleanup(bool reg, bool is_system) {
    716   if (!reg) {
    717     _AtlModule.UpdateRegistryFromResourceS(IDR_CHROMEFRAME_NPAPI, reg);
    718     UtilRemovePersistentNPAPIMarker();
    719   }
    720   // Ignore failures.
    721   return S_OK;
    722 }
    723 
    724 HRESULT RegisterAppId(bool reg, bool is_system) {
    725   return _AtlModule.UpdateRegistryAppId(reg);
    726 }
    727 
    728 HRESULT RegisterUserAgent(bool reg, bool is_system) {
    729   if (reg) {
    730     return SetChromeFrameUA(is_system, L"1");
    731   } else {
    732     return SetChromeFrameUA(is_system, NULL);
    733   }
    734 }
    735 
    736 enum RegistrationStepId {
    737   kStepSecuredMimeHandler = 0,
    738   kStepActiveDoc          = 1,
    739   kStepActiveX            = 2,
    740   kStepElevationPolicy    = 3,
    741   kStepProtocol           = 4,
    742   kStepBhoClsid           = 5,
    743   kStepBhoRegistration    = 6,
    744   kStepRegisterTypeLib    = 7,
    745   kStepNpapiCleanup       = 8,
    746   kStepAppId              = 9,
    747   kStepUserAgent          = 10,
    748   kStepEnd                = 11
    749 };
    750 
    751 enum RegistrationFlags {
    752   ACTIVEX             = 0x0001,
    753   ACTIVEDOC           = 0x0002,
    754   GCF_PROTOCOL        = 0x0004,
    755   BHO_CLSID           = 0x0008,
    756   BHO_REGISTRATION    = 0x0010,
    757   TYPELIB             = 0x0020,
    758 
    759   ALL                 = 0xFFFF
    760 };
    761 
    762 // Mux the failure step into the hresult. We take only the first four bits
    763 // and stick those into the top four bits of the facility code. We also set the
    764 // Customer bit to be polite. Graphically, we write our error code to the
    765 // bits marked with ^:
    766 //   3 3 2 2 2 2 2 2 2 2 2 2 1 1 1 1 1 1 1 1 1 1
    767 //   1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0
    768 //  +---+-+-+-----------------------+-------------------------------+
    769 //  |Sev|C|R|     Facility          |               Code            |
    770 //  +---+-+-+-----------------------+-------------------------------+
    771 //       ^   ^ ^ ^ ^
    772 // See http://msdn.microsoft.com/en-us/library/cc231198(PROT.10).aspx for
    773 // more details on HRESULTS.
    774 //
    775 // The resulting error can be extracted by:
    776 // error_code = (fiddled_hr & 0x07800000) >> 23
    777 HRESULT MuxErrorIntoHRESULT(HRESULT hr, int error_code) {
    778   DCHECK_GE(error_code, 0);
    779   DCHECK_LT(error_code, kStepEnd);
    780   COMPILE_ASSERT(kStepEnd <= 0xF, update_error_muxing_too_many_steps);
    781 
    782   // Check that our four desired bits are clear.
    783   // 0xF87FFFFF == 11111000011111111111111111111111
    784   DCHECK_EQ(static_cast<HRESULT>(hr & 0xF87FFFFF), hr);
    785 
    786   HRESULT fiddled_hr = ((error_code & 0xF) << 23) | hr;
    787   fiddled_hr |= 1 << 29;  // Set the customer bit.
    788 
    789   return fiddled_hr;
    790 }
    791 
    792 HRESULT CustomRegistration(uint16 reg_flags, bool reg, bool is_system) {
    793   if (reg && (reg_flags & (ACTIVEDOC | ACTIVEX)))
    794     reg_flags |= (TYPELIB | GCF_PROTOCOL);
    795 
    796   // Set the flag that gets checked in AddCommonRGSReplacements before doing
    797   // registration work.
    798   _AtlModule.do_system_registration_ = is_system;
    799 
    800   typedef HRESULT (*RegistrationFn)(bool reg, bool is_system);
    801   struct RegistrationStep {
    802     RegistrationStepId id;
    803     uint16 condition;
    804     RegistrationFn func;
    805   };
    806   static const RegistrationStep registration_steps[] = {
    807     { kStepSecuredMimeHandler, ACTIVEDOC, &RegisterSecuredMimeHandler },
    808     { kStepActiveDoc, ACTIVEDOC, &RegisterActiveDoc },
    809     { kStepActiveX, ACTIVEX, &RegisterActiveX },
    810     { kStepElevationPolicy, (ACTIVEDOC | ACTIVEX), &RegisterElevationPolicy },
    811     { kStepProtocol, GCF_PROTOCOL, &RegisterProtocol },
    812     { kStepBhoClsid, BHO_CLSID, &RegisterBhoClsid },
    813     { kStepBhoRegistration, BHO_REGISTRATION, &RegisterBhoIE },
    814     { kStepRegisterTypeLib, TYPELIB, &RegisterTypeLib },
    815     { kStepNpapiCleanup, ALL, &RegisterLegacyNPAPICleanup },
    816     { kStepAppId, ALL, &RegisterAppId },
    817     { kStepUserAgent, ALL, &RegisterUserAgent }
    818   };
    819 
    820   HRESULT hr = S_OK;
    821 
    822   bool rollback = false;
    823   int failure_step = 0;
    824   HRESULT step_hr = S_OK;
    825   for (int step = 0; step < arraysize(registration_steps); ++step) {
    826     if ((reg_flags & registration_steps[step].condition) != 0) {
    827       step_hr = registration_steps[step].func(reg, is_system);
    828       if (FAILED(step_hr)) {
    829         // Store only the first failing HRESULT with the step value muxed in.
    830         if (hr == S_OK) {
    831           hr = MuxErrorIntoHRESULT(step_hr, step);
    832         }
    833 
    834         // On registration if a step fails, we abort and rollback.
    835         if (reg) {
    836           rollback = true;
    837           failure_step = step;
    838           break;
    839         }
    840       }
    841     }
    842   }
    843 
    844   if (rollback) {
    845     DCHECK(reg);
    846     // Rollback the failing action and all preceding ones.
    847     for (int step = failure_step; step >= 0; --step) {
    848       registration_steps[step].func(!reg, is_system);
    849     }
    850   }
    851 
    852   return hr;
    853 }
    854 
    855 }  // namespace
    856 
    857 // DLL Entry Point
    858 extern "C" BOOL WINAPI DllMain(HINSTANCE instance,
    859                                DWORD reason,
    860                                LPVOID reserved) {
    861   UNREFERENCED_PARAMETER(instance);
    862   if (reason == DLL_PROCESS_ATTACH) {
    863 #ifndef NDEBUG
    864     // Silence traces from the ATL registrar to reduce the log noise.
    865     ATL::CTrace::s_trace.ChangeCategory(atlTraceRegistrar, 0,
    866                                         ATLTRACESTATUS_DISABLED);
    867 #endif
    868     InitGoogleUrl();
    869 
    870     g_exit_manager = new base::AtExitManager();
    871     CommandLine::Init(0, NULL);
    872     logging::LoggingSettings settings;
    873     settings.logging_dest = logging::LOG_TO_SYSTEM_DEBUG_LOG;
    874     logging::InitLogging(settings);
    875 
    876     // Log the same items as Chrome.
    877     logging::SetLogItems(true,  // enable_process_id
    878                          true,  // enable_thread_id
    879                          false, // enable_timestamp
    880                          true); // enable_tickcount
    881 
    882     DllRedirector* dll_redirector = DllRedirector::GetInstance();
    883     DCHECK(dll_redirector);
    884 
    885     if (!dll_redirector->RegisterAsFirstCFModule()) {
    886       // Someone else was here first, try and get a pointer to their
    887       // DllGetClassObject export:
    888       g_dll_get_class_object_redir_ptr =
    889           dll_redirector->GetDllGetClassObjectPtr();
    890       DCHECK(g_dll_get_class_object_redir_ptr != NULL)
    891           << "Found CF module with no DllGetClassObject export.";
    892     }
    893 
    894     // Enable trace control and transport through event tracing for Windows.
    895     logging::LogEventProvider::Initialize(kChromeFrameProvider);
    896 
    897     // Set a callback so that crash reporting can be pinned when the module is
    898     // pinned.
    899     chrome_frame::SetPinModuleCallback(&OnPinModule);
    900   } else if (reason == DLL_PROCESS_DETACH) {
    901     DllRedirector* dll_redirector = DllRedirector::GetInstance();
    902     DCHECK(dll_redirector);
    903     dll_redirector->UnregisterAsFirstCFModule();
    904 
    905     g_patch_helper.UnpatchIfNeeded();
    906 
    907     delete g_exit_manager;
    908     g_exit_manager = NULL;
    909   }
    910   return _AtlModule.DllMain(reason, reserved);
    911 }
    912 
    913 // Used to determine whether the DLL can be unloaded by OLE
    914 STDAPI DllCanUnloadNow() {
    915   return _AtlModule.DllCanUnloadNow();
    916 }
    917 
    918 // Returns a class factory to create an object of the requested type
    919 STDAPI DllGetClassObject(REFCLSID rclsid, REFIID riid, LPVOID* ppv) {
    920   chrome_frame::ScopedCrashReporting crash_reporting;
    921 
    922   // If we found another module present when we were loaded, then delegate to
    923   // that:
    924   if (g_dll_get_class_object_redir_ptr) {
    925     return g_dll_get_class_object_redir_ptr(rclsid, riid, ppv);
    926   }
    927 
    928   // Enable sniffing and switching only if asked for BHO
    929   // (we use BHO to get loaded in IE).
    930   if (rclsid == CLSID_ChromeFrameBHO) {
    931     g_patch_helper.InitializeAndPatchProtocolsIfNeeded();
    932   }
    933 
    934   return _AtlModule.DllGetClassObject(rclsid, riid, ppv);
    935 }
    936 
    937 // DllRegisterServer - Adds entries to the system registry
    938 STDAPI DllRegisterServer() {
    939   chrome_frame::ScopedCrashReporting crash_reporting;
    940   uint16 flags =  ACTIVEX | ACTIVEDOC | TYPELIB | GCF_PROTOCOL |
    941                   BHO_CLSID | BHO_REGISTRATION;
    942 
    943   HRESULT hr = CustomRegistration(flags, true, true);
    944   if (SUCCEEDED(hr)) {
    945     SetupRunOnce();
    946   }
    947 
    948   return hr;
    949 }
    950 
    951 // DllUnregisterServer - Removes entries from the system registry
    952 STDAPI DllUnregisterServer() {
    953   chrome_frame::ScopedCrashReporting crash_reporting;
    954   HRESULT hr = CustomRegistration(ALL, false, true);
    955   return hr;
    956 }
    957 
    958 // DllRegisterUserServer - Adds entries to the HKCU hive in the registry.
    959 STDAPI DllRegisterUserServer() {
    960   chrome_frame::ScopedCrashReporting crash_reporting;
    961   UINT flags =  ACTIVEX | ACTIVEDOC | TYPELIB | GCF_PROTOCOL |
    962                 BHO_CLSID | BHO_REGISTRATION;
    963 
    964   HRESULT hr = CustomRegistration(flags, TRUE, false);
    965   if (SUCCEEDED(hr)) {
    966     SetupRunOnce();
    967   }
    968 
    969   return hr;
    970 }
    971 
    972 // DllUnregisterUserServer - Removes entries from the HKCU hive in the registry.
    973 STDAPI DllUnregisterUserServer() {
    974   chrome_frame::ScopedCrashReporting crash_reporting;
    975   HRESULT hr = CustomRegistration(ALL, FALSE, false);
    976   return hr;
    977 }
    978 
    979 // Object entries go here instead of with each object, so that we can move
    980 // the objects to a lib. Also reduces magic.
    981 OBJECT_ENTRY_AUTO(CLSID_ChromeFrameBHO, Bho)
    982 OBJECT_ENTRY_AUTO(__uuidof(ChromeActiveDocument), ChromeActiveDocument)
    983 OBJECT_ENTRY_AUTO(__uuidof(ChromeFrame), ChromeFrameActivex)
    984 OBJECT_ENTRY_AUTO(__uuidof(ChromeProtocol), ChromeProtocol)
    985