AWS nitro enclaves[1] is an Amazon EC2[2] feature that allows creating
isolated execution environments, called enclaves, from Amazon EC2
instances which are used for processing highly sensitive data.
Enclaves have no persistent storage and no external networking. The
enclave VMs are based on Firecracker microvm with a vhost-vsock
device for communication with the parent EC2 instance that spawned
it and a Nitro Secure Module (NSM) device for cryptographic attestation.
The parent instance VM always has CID 3 while the enclave VM gets a
dynamic CID.
An EIF (Enclave Image Format)[3] file is used to boot an AWS nitro
enclave virtual machine. The EIF file contains the necessary kernel,
cmdline, ramdisk(s) sections to boot.
This commit adds support for limited AWS nitro enclave emulation using
a new machine type option '-M nitro-enclave'. This new machine type is
based on the 'microvm' machine type, similar to how real nitro enclave
VMs are based on Firecracker microvm. For nitro-enclave to boot from
an EIF file, the kernel and ramdisk(s) are extracted into a temporary
kernel and a temporary initrd file which are then hooked into the
regular x86 boot mechanism along with the extracted cmdline. The EIF
file path should be provided using the '-kernel' QEMU option.
The vsock and NSM devices will be implemented so that they are available
automatically in nitro-enclave machine type in the following commits.
[1] https://docs.aws.amazon.com/enclaves/latest/user/nitro-enclave.html
[2] https://aws.amazon.com/ec2/
[3] https://github.com/aws/aws-nitro-enclaves-image-format
Signed-off-by: Dorjoy Chowdhury <dorjoychy111@gmail.com>