fix(auth): allow Windows claim verification to share delete

tools/tht/internal/safeio/private_root_windows.go

@@ -154,6 +154,26 @@ func openWindowsRelativeObject(
 	disposition uint32,
 	options uint32,
 	security *ownerOnlySecurityDescriptor,
+) (windows.Handle, error) {
+	return openWindowsRelativeObjectWithShareMode(
+		parent,
+		name,
+		access,
+		disposition,
+		options,
+		security,
+		windowsRetainedHandleShareMode,
+	)
+}
+
+func openWindowsRelativeObjectWithShareMode(
+	parent windows.Handle,
+	name string,
+	access uint32,
+	disposition uint32,
+	options uint32,
+	security *ownerOnlySecurityDescriptor,
+	shareMode uint32,
 ) (windows.Handle, error) {
 	if parent == 0 || !validPrivateLeafName(name) {
 		return 0, ErrUnsafeFile
@@ -184,7 +204,7 @@ func openWindowsRelativeObject(
 		&status,
 		&allocationSize,
 		windows.FILE_ATTRIBUTE_NORMAL,
-		windowsRetainedHandleShareMode,
+		shareMode,
 		disposition,
 		options,
 		0,
@@ -345,13 +365,30 @@ func openWindowsPrivateRegularAt(
 	access uint32,
 	allowedLinks ...uint32,
 ) (*windowsPrivateRegularAt, error) {
-	handle, err := openWindowsRelativeObject(
+	return openWindowsPrivateRegularAtWithShareMode(
+		parent,
+		name,
+		access,
+		windowsRetainedHandleShareMode,
+		allowedLinks...,
+	)
+}
+
+func openWindowsPrivateRegularAtWithShareMode(
+	parent windows.Handle,
+	name string,
+	access uint32,
+	shareMode uint32,
+	allowedLinks ...uint32,
+) (*windowsPrivateRegularAt, error) {
+	handle, err := openWindowsRelativeObjectWithShareMode(
 		parent,
 		name,
 		access,
 		windows.FILE_OPEN,
 		windows.FILE_NON_DIRECTORY_FILE|windows.FILE_SYNCHRONOUS_IO_NONALERT|windows.FILE_OPEN_REPARSE_POINT,
 		nil,
+		shareMode,
 	)
 	if err != nil {
 		return nil, err
@@ -936,7 +973,13 @@ func (directory *windowsPrivateDirectory) RemoveClaim(source, claim string) (boo
 		}
 		return false, ErrUnsafeFile
 	}
-	claimed, err := openWindowsPrivateRegularAt(directory.handle, claim, windows.FILE_GENERIC_READ, 2)
+	claimed, err := openWindowsPrivateRegularAtWithShareMode(
+		directory.handle,
+		claim,
+		windows.FILE_GENERIC_READ,
+		windowsRetainedHandleShareMode|windows.FILE_SHARE_DELETE,
+		2,
+	)
 	if isWindowsRelativeNotFound(err) {
 		_ = value.Close()
 		return false, nil