EnclaveOS

https://git.distrust.co/public/enclaveos

About

A minimal, immutable, and deterministic Linux unikernel build system targeting various Trusted Execution Environments for use cases that require high security and accountability.

This is intended as a reference repository which could serve as a boilerplate to build your own hardened and immutable operating system images for high security applications.

Architecture

---
config:
  theme: base
---
C4Context
    title System Context diagram for Internet Banking System
    Boundary(enclaveos, "EnclaveOS") {
        System(kernel1,"Offline Kernel")
        System(nit,"Init System","nit")
        System(serviced,"Service Manager","serviced")
        System(guestctl,"Guest Management","guestctl")
        BiRel(guestctl,gateway-kernel,"vsock")
        BiRel(guestctl,enclave-kernel,"vsock")
        BiRel(guestctl,bootproof-agent,"vsock") 
        System(bootproof-agent,"Attestation Agent","bootproof-agent")
        Boundary(iommu, "IOMMU") {
            Boundary(enclave-vm, "Enclave VM") {
                System(enclave-kernel,"Offline Kernel")
                System(user-service,"User Provided Service")
                System(keyforkd,"Keyfork Daemon")
            }
            Boundary(gateway-vm", "Gateway VM") {
                System(gateway-kernel,"Online Kernel")
                System(enclaved,"EnclaveOS API")
                System(bootproofd,"Bootproof API")
            }
        }
        Boundary(b1,"Hardware") {   
            System(attest1,"TEE/HSM","TPM2, Nitro, TDX, SEV")
            System(nic1, "NIC", "")
            System(disk1,"Disk","")
        }
    }
    Person(user1, "Client", "End User")
    System(endorsement-api,"Platform Endorsement API","AWS,GCP,Azure")
    Rel(endorsement-api,gateway-kernel,"")
    Rel(kernel1,nit,"")
    Rel(nit,serviced,"")
    Rel(serviced,guestctl,"")
    BiRel(attest1,bootproof-agent,"")
    Rel(nic1,gateway-kernel,"iommu")
    Rel(disk1,enclave-kernel,"iommu")
    BiRel(user-service,enclave-kernel,"")
    BiRel(keyforkd,user-service,"")
    BiRel(keyforkd,enclave-kernel,"")
    BiRel(user1,gateway-kernel,"vsock")
    BiRel(gateway-kernel,bootproofd,"")
    BiRel(gateway-kernel,enclaved,"")

Platforms

Platform	Target	Status	Verified boot Method
AWS Nitro Enclaves	aws	booting	Nitro attestation API
GCP Confidential Compute	gcp	research	vTPM 2.0 attestation
Azure Confidential VMs	azure	research	vTPM 2.0 attestation
Generic/Qemu	generic	research	vTPM 2.0 attestation

Features

• Immutability
  • Root filesystem is a CPIO filesystem extracted to a RamFS at boot
• Minimalism
  • < 5MB footprint
  • Nothing is included but a kernel and your target binary by default
  • Sample "hello world" included as a default reference
  • Debug builds include busybox init shim and drop to a shell
• Determinism
  • Multiple people can build artifacts and get identical hashes
  • Allows one to prove distributed artifacts correspond to published sources
• Hardening
  • No TCP/IP network support
    • Favor using a virtual socket or physical interface to a gateway system
  • Most unessesary kernel features are disabled at compile time
  • Follow Kernel Self Protection Project recommendations

Development

Requirements

• 10GB+ free RAM
• Docker 20+
• GNU Make

Build

make