We present an interface connecting the ACL2 theorem prover with external deduction tools. The logic of ACL2 contains several constructs intended to facilitate structuring of interactive proof development, which complicates the design of such an interface. We discuss some of these complexities and develop a precise specification of the requirements from external tools for sound connection with ACL2. We also develop constructs within ACL2 to enable the developers of external tools to satisfy our specifications. 1

To my parents, Henry and Karen Reeber, and my fiancée, Carrie Pankrast, for all their love, guidance, and support. Acknowledgments Most of all, I would like to thank my thesis advisor, Warren Hunt. Warren always has the amazing ability to give me what I need, before I even ask for it. Furthermore, Warren has been a source of constant encouragement and guidance, without which I never would have started this dissertation, let alone completed it. I would also like to thank the rest of my dissertation committee, Allen Emerson, Steve Keckler, J Moore, and Anna Slobodova, for all the time and energy they spent re-viewing my research and for their great feedback both on the dissertation itself and the earlier dissertation proposal. Anna in particular provided me with copious notes that have significantly improved the quality of this dissertation. Thanks also to Sandip Ray, Simha Sethumadhavan, and Jun Sawada for providing excellent feedback on portions of this dis-sertation. A number of professors at the University of Texas have influenced my work. My

To the few people who believed I could do it even when I myself didn’t Acknowledgments This dissertation has been shaped by many people, including my teachers, collabo-rators, friends, and family. I would like to take this opportunity to acknowledge the influence they have had in my development as a person and as a scientist. First and foremost, I wish to thank my advisor J Strother Moore. J is an amazing advisor, a marvellous collaborator, an insightful researcher, an empathetic teacher, and a truly great human being. He gave me just the right balance of freedom, encouragement, and direction to guide the course of this research. My stimulating discussions with him made the act of research an experience of pure enjoyment, and helped pull me out of many low ebbs. At one point I used to believe that whenever I was stuck with a problem one meeting with J would get me back on track. Furthermore, my times together with J and Jo during Thanksgivings and other occasions always made me feel part of his family. There was no problem, technical or otherwise, that I could not discuss with J, and there was no time when

We develop a framework for mechanized certification of secure hardware systems built out of commercial off-theshelf (COTS) components purchased from untrusted vendors. Certification requires a guarantee that the fabricated system satisfies the requisite safety and security properties. Our framework facilitates this by (1) providing an unambiguous description of the requirements specification in a formal, computational logic, (2) a formalized hardware description language (HDL) to describe the implementation, and (3) mechanical tools and techniques for providing a certification of correctness and security. We illustrate the use of the framework in certifying the correctness and security properties of the netlist implementation of a voting machine using the ACL2 theorem prover.