ベスト プラクティスについてはわかりませんが、ユーザーが管理者グループに属しているアカウントによって管理者権限を持っているかどうか、またはユーザーが UAC を介してその役割にエスカレートできるかどうかを検出したい場合は、MSDN コード サンプルをご覧ください。自己エスカレーション: http://code.msdn.microsoft.com/windowsdesktop/CSUACSelfElevation-644673d3/sourcecode?fileId=21729&pathId=1041468146
この例には、現在のユーザーのトークンまたはエスカレーション トークンのいずれかを調べる MainForm.IsUserInAdminGroup() メソッドがあります。
/// <summary>
/// The function checks whether the primary access token of the process belongs
/// to user account that is a member of the local Administrators group, even if
/// it currently is not elevated.
/// </summary>
/// <returns>
/// Returns true if the primary access token of the process belongs to user
/// account that is a member of the local Administrators group. Returns false
/// if the token does not.
/// </returns>
/// <exception cref="System.ComponentModel.Win32Exception">
/// When any native Windows API call fails, the function throws a Win32Exception
/// with the last error code.
/// </exception>
internal bool IsUserInAdminGroup()
{
bool fInAdminGroup = false;
SafeTokenHandle hToken = null;
SafeTokenHandle hTokenToCheck = null;
IntPtr pElevationType = IntPtr.Zero;
IntPtr pLinkedToken = IntPtr.Zero;
int cbSize = 0;
try
{
// Open the access token of the current process for query and duplicate.
if (!NativeMethods.OpenProcessToken(Process.GetCurrentProcess().Handle,
NativeMethods.TOKEN_QUERY | NativeMethods.TOKEN_DUPLICATE, out hToken))
{
throw new Win32Exception();
}
// Determine whether system is running Windows Vista or later operating
// systems (major version >= 6) because they support linked tokens, but
// previous versions (major version < 6) do not.
if (Environment.OSVersion.Version.Major >= 6)
{
// Running Windows Vista or later (major version >= 6).
// Determine token type: limited, elevated, or default.
// Allocate a buffer for the elevation type information.
cbSize = sizeof(TOKEN_ELEVATION_TYPE);
pElevationType = Marshal.AllocHGlobal(cbSize);
if (pElevationType == IntPtr.Zero)
{
throw new Win32Exception();
}
// Retrieve token elevation type information.
if (!NativeMethods.GetTokenInformation(hToken,
TOKEN_INFORMATION_CLASS.TokenElevationType, pElevationType,
cbSize, out cbSize))
{
throw new Win32Exception();
}
// Marshal the TOKEN_ELEVATION_TYPE enum from native to .NET.
TOKEN_ELEVATION_TYPE elevType = (TOKEN_ELEVATION_TYPE)
Marshal.ReadInt32(pElevationType);
// If limited, get the linked elevated token for further check.
if (elevType == TOKEN_ELEVATION_TYPE.TokenElevationTypeLimited)
{
// Allocate a buffer for the linked token.
cbSize = IntPtr.Size;
pLinkedToken = Marshal.AllocHGlobal(cbSize);
if (pLinkedToken == IntPtr.Zero)
{
throw new Win32Exception();
}
// Get the linked token.
if (!NativeMethods.GetTokenInformation(hToken,
TOKEN_INFORMATION_CLASS.TokenLinkedToken, pLinkedToken,
cbSize, out cbSize))
{
throw new Win32Exception();
}
// Marshal the linked token value from native to .NET.
IntPtr hLinkedToken = Marshal.ReadIntPtr(pLinkedToken);
hTokenToCheck = new SafeTokenHandle(hLinkedToken);
}
}
// CheckTokenMembership requires an impersonation token. If we just got
// a linked token, it already is an impersonation token. If we did not
// get a linked token, duplicate the original into an impersonation
// token for CheckTokenMembership.
if (hTokenToCheck == null)
{
if (!NativeMethods.DuplicateToken(hToken,
SECURITY_IMPERSONATION_LEVEL.SecurityIdentification,
out hTokenToCheck))
{
throw new Win32Exception();
}
}
// Check if the token to be checked contains admin SID.
WindowsIdentity id = new WindowsIdentity(hTokenToCheck.DangerousGetHandle());
WindowsPrincipal principal = new WindowsPrincipal(id);
fInAdminGroup = principal.IsInRole(WindowsBuiltInRole.Administrator);
}
finally
{
// Centralized cleanup for all allocated resources.
if (hToken != null)
{
hToken.Close();
hToken = null;
}
if (hTokenToCheck != null)
{
hTokenToCheck.Close();
hTokenToCheck = null;
}
if (pElevationType != IntPtr.Zero)
{
Marshal.FreeHGlobal(pElevationType);
pElevationType = IntPtr.Zero;
}
if (pLinkedToken != IntPtr.Zero)
{
Marshal.FreeHGlobal(pLinkedToken);
pLinkedToken = IntPtr.Zero;
}
}
return fInAdminGroup;
}