Access control lists in password capability environments

Abstract

With reference to a protection system featuring active subjects that attempt to access passive, typed objects,we propose a set of mechanisms supporting the distribution,verification,review and revocation of access privileges. In our approach, a protection domain is a collection of access rights for the protected objects. An access control list is associated with each object to specify the access rights in each domain. Objects are grouped into clusters.To access the objects in a given cluster, a subject presents a gate referencing this cluster. The gate is a form of password capability that identifies one or more domains.The gate grants the access rights specified for these domains by the access control lists of the objects in the cluster. A subject that holds a gate and is aimed at distributing the access privileges in this gate in restricted form can reduce the gate to eliminate domains; the gate reduction procedure requires no intervention of the protection system. A small set of protection primitives allows subjects to manage objects and access control lists. Forms of revocation of access permissions are supported, at both levels of gates and access control lists

Extended pointers for memory protection in single address space systems

“…The access matrix, introduced in Section 2, can be represented in memory by columns. In this case, a list, called the access control list, is associated with each object [29]. The access control list ACL j of object B j consists of a collection of entries having the form (S i , z), where S i is the name of a subject, and z is an access authorization.…”

Password-based protection of clustered segments in distributed memory systems

“…In a well-known approach, the state of a protection system is expressed by associating an access control list with each object [19], [24], [26]. The access control list ACL G associated with object G consists of a set of entries having the form (D, AR), where D denotes a protection domain, and AR specifies the access rights for G, which are contained in D.…”