if creds.IsTemp() && !creds.IsExpired() {
			var parentPolicy string
			u, err := globalIAMSys.GetUserInfo(ctx, creds.ParentUser)
			if err != nil {
				// Parent may be "virtual" (for ldap, oidc, client tls auth,
				// custom auth plugin), so in such cases we apply no parent
				// policy. The session token will contain info about policy to
				// be applied.
				if !errors.Is(err, errNoSuchUser) {

	file := r.Form.Get("file")
	if len(file) == 0 {
		writeErrorResponseJSON(ctx, w, errorCodes.ToAPIErr(ErrInvalidRequest), r.URL)
		return
	}

	file = filepath.ToSlash(file)
	// Reject attempts to traverse parent or absolute paths.
	if hasBadPathComponent(volume) || hasBadPathComponent(file) {
		writeErrorResponse(r.Context(), w, errorCodes.ToAPIErr(ErrInvalidResourceName), r.URL)
		return
	}