fix(auth): remove Windows claims by retained handle

tools/tht/internal/safeio/claim_windows.go

@@ -123,41 +123,24 @@ func readCanonicalPrivateClaim(source, claim string, maximum int64) ([]byte, boo
 	return contents, true, nil
 }
 
-func removeCanonicalPrivateClaim(source, claim string) (bool, error) {
-	sourceFile, err := openWindowsPrivateRegular(source, 2)
-	if err != nil {
-		if isWindowsNotFound(err) && windowsPrivateClaimAbsentOrOrphan(claim) {
-			return false, nil
+func removeCanonicalPrivateClaim(source, claim string) (removed bool, resultErr error) {
+	parentPath := filepath.Dir(source)
+	sourceName := filepath.Base(source)
+	claimName := filepath.Base(claim)
+	if parentPath != filepath.Dir(claim) || !validPrivateLeafName(sourceName) || !validPrivateLeafName(claimName) {
+		return false, ErrUnsafeFile
+	}
+	directory, found, err := OpenPrivateDirectory(parentPath, false)
+	if err != nil || !found {
+		return false, ErrUnsafeFile
+	}
+	defer func() {
+		if closeErr := directory.Close(); closeErr != nil && resultErr == nil {
+			resultErr = ErrUnsafeFile
 		}
-		return false, ErrUnsafeFile
-	}
-	claimFile, err := openWindowsPrivateRegular(claim, 2)
-	if err != nil {
-		sourceFile.Close()
-		if isWindowsNotFound(err) {
-			return false, nil
-		}
-		return false, ErrUnsafeFile
-	}
-	if !sameWindowsPrivateFile(sourceFile.info, claimFile.info) {
-		sourceFile.Close()
-		claimFile.Close()
-		return false, ErrUnsafeFile
-	}
-	sourceFile.Close()
-	claimFile.Close()
-	if err := windows.DeleteFile(windows.StringToUTF16Ptr(source)); err != nil {
-		return false, ErrUnsafeFile
-	}
-	remaining, err := openWindowsPrivateRegular(claim, 1)
-	if err != nil {
-		return false, ErrUnsafeFile
-	}
-	remaining.Close()
-	if err := windows.DeleteFile(windows.StringToUTF16Ptr(claim)); err != nil {
-		return false, ErrUnsafeFile
-	}
-	return true, nil
+	}()
+	NotifyPrivateDirectoryTestHookForTest("after-canonical-private-claim-parent-open")
+	return directory.RemoveClaim(sourceName, claimName)
 }
 
 func openWindowsPrivateRegularWithAllowedLinks(path string, allowed ...uint32) (*windowsPrivateRegular, error) {