No abstract

In this paper we revisit SAM, a security architecture for microprocessors that provides memory encryption and memory verification using hash values, including a summary of its main features and an overview of other related architectures. We analyze the security of SAM architecture as originally proposed, pointing out some weaknesses in security and performance. To overcome them, we supply another hashing and protection schemes which strengthen the security and improve the performance of the first proposal. Finally, we present some experimental results comparing the old and new schemes.

No abstract

SAM is a processor extension used to protect execution of dedicated programs by preventing data disclosure and program manipulations in a multitasking environment. This paper presents an operating system design based on the Linux kernel for SAM. The design splits the kernel into a very small protected part and an unprotected part used by drivers and high level functions. Using this kernel protected and unprotected programs can be executed in parallel without diminishing the protection. The protection mechanism does not slow down the execution of unprotected programs, since it is only active during the execution of protected programs.