Towards trusted cut and paste in the X Window System

The X Window System (X) has become one of the most popular window systems available. However, to use X in a trusted environment, a variety of security issues must be addressed. Among these issues is how to mediate interwindow data moves in a manner consistent with a system's security policy. Current interpretations of existing security requirements state that interwindow moves must be subject not only to traditional access controls, but also that users must be able to perform certain operations as the data is being moved (such as review the data, or alter the data's security attributes). The paper presents the issues involved in meeting the security requirements, and describes and contrasts two possible approaches for addressing those issues.<>