Certicloud: A Novel TPM-based Approach to Ensure Cloud IaaS Security

Abstract

The security issues raised by the Cloud paradigm are not always tackled from the user point of view. For instance, considering an Infrastructure-as-a-Service (IaaS) Cloud, it is currently impossible for a user to certify in a reliable and secure way that the environment he deployed (typically a Virtual Machine(VM)) has not been corrupted, whether by malicious acts or not. Yet having this functionality would enhance the confidence on the IaaS provider and therefore attract new customers. This paper fills this need by proposing CERTICLOUD, a novel approach for the protection of IaaS platforms that relies on the concepts developed in the Trusted Computing Group (TCG) together with hardware elements, i.e., Trusted Platform Module (TPM) to offer a secured and reassuring environment. Those aspects are guaranteed by two protocols: TCRR and Verify MyVM. When the first one asserts the integrity of a remote resource and permits to exchange a private symmetric key, the second authorizes the user to detect trustfully and on demand any tampering attempt on its running VM. These protocols being key components in the proposed framework, we take very seriously their analysis against known cryptanalytic attacks. This is testified by their successful validation by AVISPA and Scyther, two reference tools for the automatic verification of security protocols. The CERTICLOUD proposal is then detailed: relying on the above protocols, this platform provides the secure storage of users environments and their safe deployment onto a virtualization framework. While the physical resources are checked by TCRR, the user can execute on demand the Verify MyVM protocol to certify the integrity of its deployed environment. Experimental results operated on a first prototype of CERTICLOUD demonstrate the feasibility and the low overhead of the approach, together with its easy implementation on recent commodity machines.