Bug 1572788 - Make nsXULAppInfo::GetUserCanElevate reuse GetElevationType. r=aklotz

`nsXULAppInfo::GetUserCanElevate` can reuse `GetElevationType` and we can remove
`VistaTokenElevationType` definition.

Differential Revision: https://phabricator.services.mozilla.com/D49691

--HG--
extra : moz-landing-system : lando

browser/app/winlauncher/LaunchUnelevated.cpp

@@ -11,22 +11,11 @@
 #include "mozilla/mscom/ProcessRuntime.h"
 #include "mozilla/RefPtr.h"
 #include "mozilla/ShellHeaderOnlyUtils.h"
+#include "mozilla/WinHeaderOnlyUtils.h"
 #include "nsWindowsHelpers.h"
 
 #include <windows.h>
 
-static mozilla::LauncherResult<TOKEN_ELEVATION_TYPE> GetElevationType(
-    const nsAutoHandle& aToken) {
-  DWORD retLen;
-  TOKEN_ELEVATION_TYPE elevationType;
-  if (!::GetTokenInformation(aToken.get(), TokenElevationType, &elevationType,
-                             sizeof(elevationType), &retLen)) {
-    return LAUNCHER_ERROR_FROM_LAST();
-  }
-
-  return elevationType;
-}
-
 static mozilla::LauncherResult<bool> IsHighIntegrity(
     const nsAutoHandle& aToken) {
   DWORD reqdLen;

toolkit/xre/nsAppRunner.cpp

@@ -904,44 +904,31 @@ nsXULAppInfo::GetLauncherProcessState(uint32_t* aResult) {
 }
 
 #ifdef XP_WIN
-// Matches the enum in WinNT.h for the Vista SDK but renamed so that we can
-// safely build with the Vista SDK and without it.
-typedef enum {
-  VistaTokenElevationTypeDefault = 1,
-  VistaTokenElevationTypeFull,
-  VistaTokenElevationTypeLimited
-} VISTA_TOKEN_ELEVATION_TYPE;
-
-// avoid collision with TokeElevationType enum in WinNT.h
-// of the Vista SDK
-#  define VistaTokenElevationType static_cast<TOKEN_INFORMATION_CLASS>(18)
-
 NS_IMETHODIMP
 nsXULAppInfo::GetUserCanElevate(bool* aUserCanElevate) {
-  HANDLE hToken;
-
-  VISTA_TOKEN_ELEVATION_TYPE elevationType;
-  DWORD dwSize;
-
-  if (!OpenProcessToken(GetCurrentProcess(), TOKEN_QUERY, &hToken) ||
-      !GetTokenInformation(hToken, VistaTokenElevationType, &elevationType,
-                           sizeof(elevationType), &dwSize)) {
+  HANDLE rawToken;
+  if (!::OpenProcessToken(::GetCurrentProcess(), TOKEN_QUERY, &rawToken)) {
     *aUserCanElevate = false;
-  } else {
-    // The possible values returned for elevationType and their meanings are:
-    //   TokenElevationTypeDefault: The token does not have a linked token
-    //     (e.g. UAC disabled or a standard user, so they can't be elevated)
-    //   TokenElevationTypeFull: The token is linked to an elevated token
-    //     (e.g. UAC is enabled and the user is already elevated so they can't
-    //      be elevated again)
-    //   TokenElevationTypeLimited: The token is linked to a limited token
-    //     (e.g. UAC is enabled and the user is not elevated, so they can be
-    //      elevated)
-    *aUserCanElevate = (elevationType == VistaTokenElevationTypeLimited);
+    return NS_OK;
   }
 
-  if (hToken) CloseHandle(hToken);
+  nsAutoHandle token(rawToken);
+  LauncherResult<TOKEN_ELEVATION_TYPE> elevationType = GetElevationType(token);
+  if (elevationType.isErr()) {
+    *aUserCanElevate = false;
+    return NS_OK;
+  }
 
+  // The possible values returned for elevationType and their meanings are:
+  //   TokenElevationTypeDefault: The token does not have a linked token
+  //     (e.g. UAC disabled or a standard user, so they can't be elevated)
+  //   TokenElevationTypeFull: The token is linked to an elevated token
+  //     (e.g. UAC is enabled and the user is already elevated so they can't
+  //      be elevated again)
+  //   TokenElevationTypeLimited: The token is linked to a limited token
+  //     (e.g. UAC is enabled and the user is not elevated, so they can be
+  //      elevated)
+  *aUserCanElevate = (elevationType.inspect() == TokenElevationTypeLimited);
   return NS_OK;
 }
 #endif

widget/windows/WinHeaderOnlyUtils.h

@@ -613,6 +613,18 @@ struct CoTaskMemFreeDeleter {
   void operator()(void* aPtr) { ::CoTaskMemFree(aPtr); }
 };
 
+inline LauncherResult<TOKEN_ELEVATION_TYPE> GetElevationType(
+    const nsAutoHandle& aToken) {
+  DWORD retLen;
+  TOKEN_ELEVATION_TYPE elevationType;
+  if (!::GetTokenInformation(aToken.get(), TokenElevationType, &elevationType,
+                             sizeof(elevationType), &retLen)) {
+    return LAUNCHER_ERROR_FROM_LAST();
+  }
+
+  return elevationType;
+}
+
 }  // namespace mozilla
 
 #endif  // mozilla_WinHeaderOnlyUtils_h