On the security of virtual machine migration and related topics
Ramya Jayaram Masti · Repository for Publications and Research Data (ETH Zurich) · 2010
The extension of trusted computing to virtual environments in order to provide secure storage and ensure system integrity presents several challenges.In particular, techniques to share a hardware TPM between several virtual machines (VM) on the same host and to appropriately secure these VMs during migration need to be devised.In this work, we provide a comprehensive overview of trusted computing and its extension to virtualization by means of virtual TPMs (vTPM).We analyze existing vTPM designs and related VM-vTPM migration protocols and derive a set of requirements for the secure VM-vTPM migration.We then propose a secure migration protocol using a novel vTPM key hierarchy that satisfies these requirements.We implement our protocol and evaluate its performance using different ciphers and VM RAM sizes.Our results show that both RC4 and 128-bit AES are efficient as underlying ciphers as opposed to 3DES which introduces a significant overhead on the migration process.Moreover, the end-to-end migration time experienced by the end user (using RC4 or 128-bit AES as the underlying cipher) increases only by approximately 10% compared to the insecure migration when VM RAM size is larger than 512 MB.This overhead may be tolerable in certain applications depending on the used hardware.Thus, secure VM-vTPM migration can be practical.