Title
Eliminating the hypervisor attack surface for a more secure cloud
Abstract
Cloud computing is quickly becoming the platform of choice for many web services. Virtualization is the key underlying technology enabling cloud providers to host services for a large number of customers. Unfortunately, virtualization software is large, complex, and has a considerable attack surface. As such, it is prone to bugs and vulnerabilities that a malicious virtual machine (VM) can exploit to attack or obstruct other VMs -- a major concern for organizations wishing to move to the cloud. In contrast to previous work on hardening or minimizing the virtualization software, we eliminate the hypervisor attack surface by enabling the guest VMs to run natively on the underlying hardware while maintaining the ability to run multiple VMs concurrently. Our NoHype system embodies four key ideas: (i) pre-allocation of processor cores and memory resources, (ii) use of virtualized I/O devices, (iii) minor modifications to the guest OS to perform all system discovery during bootup, and (iv) avoiding indirection by bringing the guest virtual machine in more direct contact with the underlying hardware. Hence, no hypervisor is needed to allocate resources dynamically, emulate I/O devices, support system discovery after bootup, or map interrupts and other identifiers. NoHype capitalizes on the unique use model in cloud computing, where customers specify resource requirements ahead of time and providers offer a suite of guest OS kernels. Our system supports multiple tenants and capabilities commonly found in hosted cloud infrastructures. Our prototype utilizes Xen 4.0 to prepare the environment for guest VMs, and a slightly modified version of Linux 2.6 for the guest OS. Our evaluation with both SPEC and Apache benchmarks shows a roughly 1% performance gain when running applications on NoHype compared to running them on top of Xen 4.0. Our security analysis shows that, while there are some minor limitations with cur- rent commodity hardware, NoHype is a significant advance in the security of cloud computing.
Year
DOI
Venue
2011
10.1145/2046707.2046754
ACM Conference on Computer and Communications Security
Keywords
Field
DocType
cloud provider,virtualization software,guest os,hypervisor attack surface,guest vms,secure cloud,cloud computing,o device,underlying hardware,guest virtual machine,guest os kernel,cloud infrastructure,web service,multicore,security analysis,virtual machine,virtualization,hardware security
Virtualization,Virtual machine,Attack surface,Storage hypervisor,Computer science,Computer security,Hypervisor,Exploit,Cloud computing security,Operating system,Embedded system,Cloud computing
Conference
Citations 
PageRank 
References 
64
2.03
23
Authors
4
Name
Order
Citations
PageRank
Jakub Szefer139837.00
Eric Keller280863.07
Ruby Lee32460261.28
Jennifer Rexford4143781195.34