Consolidate approach for conditional tests that check for privileged processes (#78793)

* Consolidate approach for conditional tests that check for privileged processes

* Simpler privileged process helpers

* Revert SLN file changes

* Remove platform-specific helpers for privileged process conditions

* Fix System.IO tests for unix-specific privileged process scenarios

* Browser does not support privileged processes

* Fix System.IO tests for unix-specific privileged process scenarios

* Enable the Environment.IsPrivilegedProcess test for browser

* PR feedback

Omit [PlatformSpecific] in modified tests that are in platform-specific test files.

Remove [Outerloop] attributes from privileged process tests.

Better multithreaded handling in PlatformDetection.IsPrivilegedProcess

Author: jeffhandley

src/libraries/Common/tests/System/IO/ReparsePointUtilities.cs

@@ -60,7 +60,7 @@ public static partial class MountHelper
         // Reduce the risk we accidentally stop running these altogether
         // on Windows, due to a bug in CreateSymbolicLink
         if (!success && PlatformDetection.IsWindows)
-            Assert.True(!PlatformDetection.IsWindowsAndElevated);
+            Assert.False(PlatformDetection.IsPrivilegedProcess);
 
         return success;
     });

src/libraries/Common/tests/TestUtilities/System/AdminHelpers.cs

@@ -34,6 +34,12 @@ public static int RunAsSudo(string commandLine)
 
         public static unsafe bool IsProcessElevated()
         {
+            // Browser does not have the concept of an elevated process
+            if (RuntimeInformation.IsOSPlatform(OSPlatform.Create("BROWSER")))
+            {
+                return false;
+            }
+
             if (!RuntimeInformation.IsOSPlatform(OSPlatform.Windows))
             {
                 uint userId = Interop.Sys.GetEUid();

src/libraries/Common/tests/TestUtilities/System/IO/FileCleanupTestBase.cs

@@ -14,12 +14,8 @@ namespace System.IO
     /// <summary>Base class for test classes the use temporary files that need to be cleaned up.</summary>
     public abstract partial class FileCleanupTestBase : IDisposable
     {
-        private static readonly Lazy<bool> s_isElevated = new Lazy<bool>(() => AdminHelpers.IsProcessElevated());
-
         private string fallbackGuid = Guid.NewGuid().ToString("N").Substring(0, 10);
 
-        protected static bool IsProcessElevated => s_isElevated.Value;
-
         /// <summary>Initialize the test class base.  This creates the associated test directory.</summary>
         protected FileCleanupTestBase(string tempDirectory = null)
         {

src/libraries/Common/tests/TestUtilities/System/PlatformDetection.Unix.cs

@@ -55,10 +55,6 @@ public static partial class PlatformDetection
         public static bool IsNotFedoraOrRedHatFamily => !IsFedora && !IsRedHatFamily;
         public static bool IsNotDebian10 => !IsDebian10;
 
-        public static bool IsSuperUser => IsBrowser || IsWindows ? false : libc.geteuid() == 0;
-
-        public static bool IsUnixAndSuperUser => !IsWindows && IsSuperUser;
-
         public static Version OpenSslVersion => !IsOSXLike && !IsWindows && !IsAndroid ?
             GetOpenSslVersion() :
             throw new PlatformNotSupportedException();

src/libraries/Common/tests/TestUtilities/System/PlatformDetection.Windows.cs

@@ -248,31 +248,8 @@ public static bool IsInAppContainer
             }
         }
 
-        public static bool CanRunImpersonatedTests => PlatformDetection.IsNotWindowsNanoServer && PlatformDetection.IsWindowsAndElevated;
+        public static bool CanRunImpersonatedTests => PlatformDetection.IsNotWindowsNanoServer && PlatformDetection.IsWindows && PlatformDetection.IsPrivilegedProcess;
 
         public static bool IsWindowsX86OrX64 => PlatformDetection.IsWindows && (PlatformDetection.IsX86Process || PlatformDetection.IsX64Process);
-
-        private static int s_isWindowsElevated = -1;
-        public static bool IsWindowsAndElevated
-        {
-            get
-            {
-                if (s_isWindowsElevated != -1)
-                    return s_isWindowsElevated == 1;
-
-                if (!IsWindows || IsInAppContainer)
-                {
-                    s_isWindowsElevated = 0;
-                    return false;
-                }
-
-                s_isWindowsElevated = AdminHelpers.IsProcessElevated() ? 1 : 0;
-
-                return s_isWindowsElevated == 1;
-            }
-        }
-
-        public static bool IsWindowsAndNotElevated
-            => IsWindows && !IsWindowsAndElevated;
     }
 }

src/libraries/Common/tests/TestUtilities/System/PlatformDetection.cs

@@ -73,6 +73,23 @@ public static partial class PlatformDetection
         public static bool Is64BitProcess => IntPtr.Size == 8;
         public static bool IsNotWindows => !IsWindows;
 
+        private static volatile int s_isPrivilegedProcess = -1;
+        public static bool IsPrivilegedProcess
+        {
+            get
+            {
+                int p = s_isPrivilegedProcess;
+                if (p == -1)
+                {
+                    s_isPrivilegedProcess = p = AdminHelpers.IsProcessElevated() ? 1 : 0;
+                }
+
+                return p == 1;
+            }
+        }
+
+        public static bool IsNotPrivilegedProcess => !IsPrivilegedProcess;
+
         public static bool IsMarshalGetExceptionPointersSupported => !IsMonoRuntime && !IsNativeAot;
 
         private static readonly Lazy<bool> s_isCheckedRuntime = new Lazy<bool>(() => AssemblyConfigurationEquals("Checked"));

src/libraries/Common/tests/TestUtilities/System/WindowsIdentityFixture.cs

@@ -39,7 +39,8 @@ public sealed partial class WindowsTestAccount : IDisposable
 
         public WindowsTestAccount(string userName)
         {
-            Assert.True(PlatformDetection.IsWindowsAndElevated);
+            Assert.True(PlatformDetection.IsWindows);
+            Assert.True(PlatformDetection.IsPrivilegedProcess);
 
             _userName = userName;
             Password = GeneratePassword();

src/libraries/System.Diagnostics.Process/tests/ProcessStartInfoTests.cs

@@ -27,7 +27,8 @@ public class ProcessStartInfoTests : ProcessTestBase
         private const string ItemSeparator = "CAFF9451396B4EEF8A5155A15BDC2080"; // random string that shouldn't be in any env vars; used instead of newline to separate env var strings
 
         private static bool IsAdmin_IsNotNano_RemoteExecutorIsSupported
-            => PlatformDetection.IsWindowsAndElevated && PlatformDetection.IsNotWindowsNanoServer && RemoteExecutor.IsSupported;
+            => PlatformDetection.IsWindows && PlatformDetection.IsNotWindowsNanoServer
+            && PlatformDetection.IsPrivilegedProcess && RemoteExecutor.IsSupported;
 
         [Fact]
         public void TestEnvironmentProperty()

src/libraries/System.Diagnostics.Process/tests/ProcessTests.Unix.cs

@@ -20,7 +20,7 @@ namespace System.Diagnostics.Tests
 {
     public partial class ProcessTests : ProcessTestBase
     {
-        private static bool IsRemoteExecutorSupportedAndOnUnixAndSuperUser => RemoteExecutor.IsSupported && PlatformDetection.IsUnixAndSuperUser;
+        private static bool IsRemoteExecutorSupportedAndPrivilegedProcess => RemoteExecutor.IsSupported && PlatformDetection.IsPrivilegedProcess;
 
         [Fact]
         private void TestWindowApisUnix()
@@ -456,7 +456,7 @@ public void ProcessStart_UseShellExecuteTrue_OpenUrl_SuccessfullyReadsArgumentAr
             }
         }
 
-        [ConditionalFact(typeof(PlatformDetection), nameof(PlatformDetection.IsUnixAndSuperUser))]
+        [ConditionalFact(typeof(PlatformDetection), nameof(PlatformDetection.IsPrivilegedProcess))]
         public void TestPriorityClassUnix()
         {
             CreateDefaultProcess();
@@ -478,11 +478,11 @@ public void TestPriorityClassUnix()
             }
             catch (Win32Exception ex)
             {
-                Assert.True(!PlatformDetection.IsSuperUser, $"Failed even though superuser {ex.ToString()}");
+                Assert.False(PlatformDetection.IsPrivilegedProcess, $"Failed even though superuser {ex.ToString()}");
             }
         }
 
-        [ConditionalFact(typeof(PlatformDetection), nameof(PlatformDetection.IsUnixAndSuperUser))]
+        [ConditionalFact(typeof(PlatformDetection), nameof(PlatformDetection.IsPrivilegedProcess))]
         public void TestBasePriorityOnUnix()
         {
             CreateDefaultProcess();
@@ -499,7 +499,7 @@ public void TestBasePriorityOnUnix()
             }
             catch (Win32Exception ex)
             {
-                Assert.True(!PlatformDetection.IsSuperUser, $"Failed even though superuser {ex.ToString()}");
+                Assert.False(PlatformDetection.IsPrivilegedProcess, $"Failed even though superuser {ex.ToString()}");
             }
         }
 
@@ -596,8 +596,7 @@ public void TestCheckChildProcessUserAndGroupIds()
         /// Tests when running as root and starting a new process as a normal user,
         /// the new process doesn't have elevated privileges.
         /// </summary>
-        [ConditionalTheory(nameof(IsRemoteExecutorSupportedAndOnUnixAndSuperUser))]
-        [OuterLoop("Needs sudo access")]
+        [ConditionalTheory(nameof(IsRemoteExecutorSupportedAndPrivilegedProcess))]
         [InlineData(true)]
         [InlineData(false)]
         public unsafe void TestCheckChildProcessUserAndGroupIdsElevated(bool useRootGroups)
@@ -743,7 +742,6 @@ private static async Task<bool> TryWaitProcessReapedAsync(int pid, int timeoutMs
         /// Tests the ProcessWaitState reference count drops to zero.
         /// </summary>
         [ConditionalFact(typeof(RemoteExecutor), nameof(RemoteExecutor.IsSupported))]
-        [PlatformSpecific(TestPlatforms.AnyUnix)] // Test validates Unix implementation
         public async Task TestProcessWaitStateReferenceCount()
         {
             using (var exitedEventSemaphore = new SemaphoreSlim(0, 1))
@@ -833,7 +831,6 @@ public void TestProcessRecycledPid()
             Assert.True(foundRecycled);
         }
 
-        [PlatformSpecific(TestPlatforms.AnyUnix)]
         [ConditionalTheory(typeof(RemoteExecutor), nameof(RemoteExecutor.IsSupported))]
         [InlineData("/dev/stdin",  O_RDONLY)]
         [InlineData("/dev/stdout", O_WRONLY)]

src/libraries/System.Diagnostics.Process/tests/ProcessTests.cs

@@ -2546,7 +2546,8 @@ public void Start_PassesArgumentsList_WhichGetsEscaped()
             }
         }
 
-        [ConditionalFact(typeof(PlatformDetection), nameof(PlatformDetection.IsWindowsAndNotElevated))]
+        [PlatformSpecific(TestPlatforms.Windows)]
+        [ConditionalFact(typeof(PlatformDetection), nameof(PlatformDetection.IsNotPrivilegedProcess))]
         public void NonElevatedUser_QueryProcessNameOfSystemProcess()
         {
             const string Services = "services";

src/libraries/System.Diagnostics.Tracing/tests/BasicEventSourceTest/FuzzyTests.Etw.cs

@@ -1,6 +1,7 @@
 // Licensed to the .NET Foundation under one or more agreements.
 // The .NET Foundation licenses this file to you under the MIT license.
 
+using System;
 using System.Collections.Generic;
 #if USE_MDT_EVENTSOURCE
 using Microsoft.Diagnostics.Tracing;
@@ -14,7 +15,7 @@ public partial class FuzzyTests
     {
         static partial void Test_Write_Fuzzy_TestEtw(List<SubTest> tests, EventSource logger)
         {
-            if (TestUtilities.IsProcessElevated)
+            if (PlatformDetection.IsPrivilegedProcess)
             {
                 using (var listener = new EtwListener())
                 {

src/libraries/System.Diagnostics.Tracing/tests/BasicEventSourceTest/TestEventCounter.Etw.cs

@@ -8,10 +8,7 @@ namespace BasicEventSourceTests
 {
     public partial class TestEventCounter
     {
-        // Specifies whether the process is elevated or not.
-        private static bool IsProcessElevated => Environment.IsPrivilegedProcess;
-
-        [ConditionalFact(nameof(IsProcessElevated))]
+        [ConditionalFact(typeof(PlatformDetection), nameof(PlatformDetection.IsPrivilegedProcess))]
         [ActiveIssue("https://github.com/dotnet/runtime/issues/25035")]
         public void Test_Write_Metric_ETW()
         {

src/libraries/System.Diagnostics.Tracing/tests/BasicEventSourceTest/TestUtilities.cs

@@ -15,9 +15,6 @@ namespace BasicEventSourceTests
 {
     internal class TestUtilities
     {
-        // Specifies whether the process is elevated or not.
-        internal static bool IsProcessElevated => Environment.IsPrivilegedProcess;
-
         /// <summary>
         /// Confirms that there are no EventSources running.
         /// </summary>

src/libraries/System.Diagnostics.Tracing/tests/BasicEventSourceTest/TestsManifestGeneration.Etw.cs

@@ -25,9 +25,8 @@ namespace BasicEventSourceTests
     public partial class TestsManifestGeneration
     {
         // Specifies whether the process is elevated or not.
-        private static bool IsProcessElevated => Environment.IsPrivilegedProcess;
         private static bool IsProcessElevatedAndNotWindowsNanoServerAndRemoteExecutorSupported =>
-            IsProcessElevated && PlatformDetection.IsNotWindowsNanoServer && RemoteExecutor.IsSupported;
+            PlatformDetection.IsPrivilegedProcess && PlatformDetection.IsNotWindowsNanoServer && RemoteExecutor.IsSupported;
 
         /// ETW only works with elevated process
         [ConditionalFact(nameof(IsProcessElevatedAndNotWindowsNanoServerAndRemoteExecutorSupported))]

src/libraries/System.Diagnostics.Tracing/tests/BasicEventSourceTest/TestsUserErrors.Etw.cs

@@ -21,7 +21,7 @@ public void Test_BadEventSource_MismatchedIds_WithEtwListener()
         {
             // We expect only one session to be on when running the test but if a ETW session was left
             // hanging, it will confuse the EventListener tests.
-            if (TestUtilities.IsProcessElevated)
+            if (PlatformDetection.IsPrivilegedProcess)
             {
                 EtwListener.EnsureStopped();
             }
@@ -31,7 +31,7 @@ public void Test_BadEventSource_MismatchedIds_WithEtwListener()
 
             var listenerGenerators = new List<Func<Listener>> { () => new EventListenerListener() };
 
-            if (TestUtilities.IsProcessElevated)
+            if (PlatformDetection.IsPrivilegedProcess)
             {
                 listenerGenerators.Add(() => new EtwListener());
             }

src/libraries/System.Diagnostics.Tracing/tests/BasicEventSourceTest/TestsWrite.Etw.cs

@@ -11,9 +11,8 @@ namespace BasicEventSourceTests
     public partial class TestsWrite
     {
         // Specifies whether the process is elevated or not.
-        private static bool IsProcessElevated => Environment.IsPrivilegedProcess;
         private static bool IsProcessElevatedAndNotWindowsNanoServer =>
-            IsProcessElevated && PlatformDetection.IsNotWindowsNanoServer; // ActiveIssue: https://github.com/dotnet/runtime/issues/26197
+            PlatformDetection.IsPrivilegedProcess && PlatformDetection.IsNotWindowsNanoServer; // ActiveIssue: https://github.com/dotnet/runtime/issues/26197
 
         /// <summary>
         /// Tests the EventSource.Write[T] method (can only use the self-describing mechanism).
@@ -30,7 +29,7 @@ public void Test_Write_T_ETW()
 
         [ActiveIssue("https://github.com/dotnet/runtime/issues/21295", TargetFrameworkMonikers.NetFramework)]
         [ActiveIssue("https://github.com/dotnet/runtime/issues/25035")]
-        [ConditionalFact(nameof(IsProcessElevated))]
+        [ConditionalFact(typeof(PlatformDetection), nameof(PlatformDetection.IsPrivilegedProcess))]
         public void Test_Write_T_In_Manifest_Serialization_WithEtwListener()
         {
             using (var eventListener = new EventListenerListener())

src/libraries/System.Diagnostics.Tracing/tests/BasicEventSourceTest/TestsWriteEvent.Etw.cs

@@ -11,9 +11,8 @@ namespace BasicEventSourceTests
     partial class TestsWriteEvent
     {
         // Specifies whether the process is elevated or not.
-        private static bool IsProcessElevated => Environment.IsPrivilegedProcess;
         private static bool IsProcessElevatedAndNotWindowsNanoServer =>
-            IsProcessElevated && PlatformDetection.IsNotWindowsNanoServer; // ActiveIssue: https://github.com/dotnet/runtime/issues/26197
+            PlatformDetection.IsPrivilegedProcess && PlatformDetection.IsNotWindowsNanoServer; // ActiveIssue: https://github.com/dotnet/runtime/issues/26197
 
         /// <summary>
         /// Tests WriteEvent using the manifest based mechanism.
@@ -84,7 +83,7 @@ public void Test_WriteEvent_ByteArray_SelfDescribing_ETW()
 
         static partial void Test_WriteEvent_AddEtwTests(List<SubTest> tests, EventSourceTest logger)
         {
-            if (!IsProcessElevated)
+            if (!PlatformDetection.IsPrivilegedProcess)
             {
                 return;
             }

src/libraries/System.Diagnostics.Tracing/tests/BasicEventSourceTest/TestsWriteEventToListener.Etw.cs

@@ -14,10 +14,7 @@ namespace BasicEventSourceTests
 {
     public partial class TestsWriteEventToListener
     {
-        // Specifies whether the process is elevated or not.
-        private static bool IsProcessElevated => Environment.IsPrivilegedProcess;
-
-        [ConditionalFact(nameof(IsProcessElevated))]
+        [ConditionalFact(typeof(PlatformDetection), nameof(PlatformDetection.IsPrivilegedProcess))]
         public void Test_WriteEvent_TransferEvents()
         {
             TestUtilities.CheckNoEventSourcesRunning("Start");

src/libraries/System.Formats.Tar/tests/TarEntry/TarEntry.ExtractToFile.Tests.Unix.cs

@@ -23,7 +23,7 @@ public static IEnumerable<object[]> GetFormatsAndSpecialFiles()
             }
         }
 
-        [ConditionalTheory(nameof(IsRemoteExecutorSupportedAndOnUnixAndSuperUser))]
+        [ConditionalTheory(nameof(IsRemoteExecutorSupportedAndPrivilegedProcess))]
         [MemberData(nameof(GetFormatsAndSpecialFiles))]
         public void Extract_SpecialFiles(TarEntryFormat format, TarEntryType entryType)
         {
@@ -36,7 +36,7 @@ public void Extract_SpecialFiles(TarEntryFormat format, TarEntryType entryType)
             Verify_Extract_SpecialFiles(destination, entry, entryType);
         }
 
-        [ConditionalTheory(nameof(IsRemoteExecutorSupportedAndOnUnixAndSuperUser))]
+        [ConditionalTheory(nameof(IsRemoteExecutorSupportedAndPrivilegedProcess))]
         [MemberData(nameof(GetFormatsAndSpecialFiles))]
         public async Task Extract_SpecialFiles_Async(TarEntryFormat format, TarEntryType entryType)
         {

src/libraries/System.Formats.Tar/tests/TarFile/TarFile.ExtractToDirectory.File.Tests.Unix.cs

@@ -9,7 +9,7 @@ namespace System.Formats.Tar.Tests
 {
     public partial class TarFile_ExtractToDirectory_File_Tests : TarTestsBase
     {
-        [ConditionalFact(nameof(IsUnixButNotSuperUser))]
+        [ConditionalFact(typeof(PlatformDetection), nameof(PlatformDetection.IsNotPrivilegedProcess))]
         public void Extract_SpecialFiles_Unix_Unelevated_ThrowsUnauthorizedAccess()
         {
             string originalFileName = GetTarFilePath(CompressionMethod.Uncompressed, TestTarFormat.ustar, "specialfiles");

src/libraries/System.Formats.Tar/tests/TarFile/TarFile.ExtractToDirectoryAsync.File.Tests.Unix.cs

@@ -10,7 +10,7 @@ namespace System.Formats.Tar.Tests
 {
     public partial class TarFile_ExtractToDirectoryAsync_File_Tests : TarTestsBase
     {
-        [ConditionalFact(nameof(IsUnixButNotSuperUser))]
+        [ConditionalFact(typeof(PlatformDetection), nameof(PlatformDetection.IsNotPrivilegedProcess))]
         public async Task Extract_SpecialFiles_Unix_Unelevated_ThrowsUnauthorizedAccess_Async()
         {
             using (TempDirectory root = new TempDirectory())

src/libraries/System.Formats.Tar/tests/TarReader/TarReader.TarEntry.ExtractToFile.Tests.Unix.cs

@@ -9,8 +9,9 @@ namespace System.Formats.Tar.Tests
 {
     public partial class TarReader_TarEntry_ExtractToFile_Tests : TarTestsBase
     {
-        [PlatformSpecific(TestPlatforms.AnyUnix & ~TestPlatforms.tvOS)] // https://github.com/dotnet/runtime/issues/68360
-        [ConditionalFact(nameof(IsUnixButNotSuperUser), nameof(IsNotLinuxBionic))]
+        [SkipOnPlatform(TestPlatforms.tvOS, "https://github.com/dotnet/runtime/issues/68360")]
+        [SkipOnPlatform(TestPlatforms.LinuxBionic, "Not supported on Bionic")]
+        [ConditionalFact(typeof(PlatformDetection), nameof(PlatformDetection.IsNotPrivilegedProcess))]
         public void SpecialFile_Unelevated_Throws()
         {
             using TempDirectory root = new TempDirectory();

src/libraries/System.Formats.Tar/tests/TarReader/TarReader.TarEntry.ExtractToFileAsync.Tests.Unix.cs

@@ -9,8 +9,9 @@ namespace System.Formats.Tar.Tests
 {
     public partial class TarReader_TarEntry_ExtractToFileAsync_Tests : TarTestsBase
     {
-        [PlatformSpecific(TestPlatforms.AnyUnix & ~TestPlatforms.tvOS)] // https://github.com/dotnet/runtime/issues/68360
-        [ConditionalFact(nameof(IsUnixButNotSuperUser), nameof(IsNotLinuxBionic))]
+        [SkipOnPlatform(TestPlatforms.LinuxBionic, "Unsupported on Bionic")]
+        [SkipOnPlatform(TestPlatforms.tvOS, "https://github.com/dotnet/runtime/issues/68360")]
+        [ConditionalFact(typeof(PlatformDetection), nameof(PlatformDetection.IsNotPrivilegedProcess))]
         public async Task SpecialFile_Unelevated_Throws_Async()
         {
             using (TempDirectory root = new TempDirectory())