Attestation Agent

Attestation Agent (AA for short) is an user space service for attestation procedure. In Kata Confidential Containers (Kata CC for short), AA implements the WrapKey API defined by keyprovider protocol, which is responsible for performing attestation and obtaining the Key Encryption Key (KEK for short) from Key Broker Service (KBS for short) , or requesting KBS to decrypt the encrypted payload stored in the image layer annotation.

Current consumers of AA include:

• ocicrypt-rs
• ocicrypt

Usage

Here are the steps of building and running AA:

Build

Build and install AA with all KBC modules:

git glone https://github.com/containers/attestation-agent
cd attestation-agent
make && make install

or explicitly specify the KBS modules it contains. Taking sample_kbc as example:

make KBC=sample_kbc

Musl

To build and install with musl, just run:

make MUSL=1 && make install

Run

For help information, just run:

attestation-agent --help

Start AA and use grpc_sock parameter to specify the endpoint of AA's keyprovider service, e.g, listen on local 47777 port:

attestation-agent --grpc_sock 127.0.0.1:47777

If you want to see the runtime log:

RUST_LOG=attestation_agent attestation-agent --grpc_sock 127.0.0.1:4777

Supported KBC modules

AA provides a flexible KBC module mechanism to support different KBS protocols required to make the communication between KBC and KBS. If the KBC modules currently supported by AA cannot meet your use requirement (e.g, need to use a new KBS protocol), you can write a new KBC module complying with the KBC development GUIDE. Welcome to contribute new KBC module to this project!

List of supported KBC modules:

KBC module name	README	KBS protocol	Maintainer
sample_kbc	Null	Null	Attestation Agent Authors
offline_fs_kbc	Offline file system KBC	Null	IBM
eaa_kbc	EAA KBC	EAA protocol	Alibaba Cloud
offline_sev_kbc	Offline SEV KBC	Null	IBM