A Security Bootstrap and Measurements

Security bootstrap is important to the platform security. If the bootstrap is not secure, Rootkits, Viruses and Trojan horses may be loaded into kernel, thus the following defenses built on the compromised kernel may be useless. In this paper, a trusted-computing based security bootstrap is introduced. We modify trust chain defined by Trusted Computing Group slightly by introducing a new component called PMBR, to implement a more flexible security bootstrap. Comparing against existing works, our contributions are as follows: (1) Our approach can automatically recover programs being attacked. Furthermore, the "attack codes" inserted by attackers can be extracted and their corresponding physical addresses can be located at the same time. (2) We theoretically prove the security of the modified trust chain. (3) We investigate the formal development of PMBR based on B method.