Portable devices have become day-to-day necessities in our lives. These devices have several critical constraints due to their small size and environment, relying on the importance of middleware in the pervasive computing environment. The significance of security is well-known in this field and it is long overdue to have middleware in the pervasive computing environment that deals with security. In this paper, we present S-MARKS, middleware that is secure by design. Features of S-MARKS include validating devices, discovering resources, modeling trust, handling malicious recommendations, and avoiding privacy violation.