]> Alibaba Cloud Intelligence Group

Hangzhou Zhejiang China dengjuan.deng@alibaba-inc.com

General Internet Engineering Task Force keyword Confidential virtual machine (CVM) in the cloud environment is a use case of confidential computing where VM confidentiality is enabled by hardware. A cloud user’s CVM is isolated from the hypervisor provided by its cloud service provider, meaning the cloud service provider cannot access the workload and data in the CVM. This is used in the scenario where a cloud user intends to protect its sensitive workload and data from cloud service provider while at the same time desires to utilize the advantages of cloud technology. This document specifies the CVM provisioning in cloud environment including the provisioning process and protocol, and the security requirements.

Introduction Confidential computing allows for workload and data protection in use leveraging hardware-based security technology. Confidential virtual machine (CVM) in cloud environment is a use case of confidential computing. It allows a cloud user to migrate its sensitive workload and data onto cloud and still protect them from cloud service provider and the hosting environment, such as hypervisor, virtual machine manager, host OS. Moreover, another benefit of using CVM is that no changes are needed for an application to be able to run in a CVM. It has witnessed an increase in the CVM provisioning and deployment in cloud. This document illustrates the provisioning process and protocol of CVM in cloud environment and also the security requirements.

CVM Provisioning in Cloud

Overview For a cloud user to create and manage CVM instance on cloud infrastructure, CVM provision process in cloud consists of the following steps:

• Enabling confidential computing feature for CVM: Configure the firmware to enable the confidential computing feature for CVM.

• Creating CVM instance: Specify the parameters for the CVM instance and create the instance.

• Verifying CVM: Verify whether a running VM is a CVM.

There may be other steps including:

• Reviewing measurements: Check the measured stored in the CVM.

• Retrieving remote attestation report: Check the remote attestation report of the CVM.

• CVM Live Migration: Migrate a live CVM to another instance.

The rest of the clause in this section describes each step above and the required message exchange between a user side (using a client), resource manager in the cloud, and platform of the server. The following clauses mainly describes what is specific to CVM provision, and normal VM provision involved is not the focus.

Enabling Confidential Computing Feature for CVM For a server to be able to host CVM, certain booting parameters need to be configured to support the confidential computing feature for CVM. For example, to create a AMD CVM, the features, memory encryption and secure encrypted virtualization, need to be enabled. The server is then running with these features enabled. This step is performed by the administrator of the server.

Creating CVM Instance Cloud service providers need to provide to cloud users the option of CVM instance, and the underlying hardware choices supporting CVM. In creating a CVM, cloud users need to set, among others, the VM type to be a CVM, and choose the hardware on which the CVM to be running.

Verifying CVM A cloud user needs to be able to check whether a running VM is a CVM or not.

Reviewing Measures

Retrieving Remote Attestation Report

Migrating a live CVM

Message Definitions

IANA Considerations This memo includes no request to IANA.

Security Considerations In addition to the hardware-based isolation of CVM from hypervisor, host OS, virtual machine monitor/manager, other CVMs, a CVM may support:

• Memory encryption
• Secure boot
• Remote attestation

This document should not affect the security of the Internet.