A Secure and Reliable Platform Configuration Change Reporting Mechanism for Trusted Computing Enhanced Secure Channels

The security of well established secure channel technologies like transport layer security (TLS) or IP security (IPSec) can be significantly improved by emerging concepts like trusted computing. The use of trusted platform modules (TPMs) offers new methods for improving the security of these well established technologies. How secure channel technologies can be adapted to use trusted computing concepts is subject to current research. A major part of this research addresses the integration of the TCG´s specified remote attestation. Remote attestation enables a platform to provide a trustworthy proof of its current configuration (i.e. software that has been loaded on the platform). Hence, based on this proof, a remote platform can decide whether to open a channel to another platform or not. In current approaches, the proof of the platform configuration is processed before a secure channel is established, which is not opened if the reported configuration is not accepted by the hosts. However, one important problem has not been solved yet. Currently, no satisfying solution how the change of a platform´s configuration can be securely and reliably reported to the remote platform whilst a channel is open, exists. A reliable method to provide a proof for a configuration change can be implemented with only minor modifications of the TPM specification and the TLS protocol. Experimental results show that it is possible to implement this proof mechanism with only a few additional TPM commands.