Build Environment track

No requirements—L0 represents the lack of any sort of build environment provenance.

Development or test builds of software that are built and run on a local machine, such as unit tests.

n/a

n/a

The build image (i.e., VM or container image) used to instantiate the build environment has SLSA Build Provenance showing how the image was built.

Build platforms and organizations wanting to ensure a baseline level of integrity for build environments at the time of build image distribution.

• Build Image Producer:

  • MUST automatically generate SLSA Build L2 or higher Provenance for created build images (i.e., VM or container images).
  • MUST allow independent automatic verification of a build image’s SLSA Build Provenance. If the build image artifact cannot be published, for example due to intellectual property concerns, an attestation asserting the expected hash value of the build image MUST be generated and distributed instead (e.g., using SCAI or a Release Attestation). If the full Build Provenance document cannot be disclosed, a VSA asserting the build image’s SLSA Provenance MUST be distributed instead.

• Build Platform:

  • MUST meet SLSA Build L2 requirements.
  • Prior to the instantiation of a new build environment, the SLSA Provenance for the selected build image MUST be automatically verified. A signed attestation to the result of the SLSA Provenance verification MUST be generated and distributed (e.g., via a VSA).

Provides evidence that a build image was built from the advertised source and build process.

The build environment is measured and authenticated by the compute platform upon instantiation, attesting to the integrity of the initial state of the environment prior to executing a build.

Organizations wanting to ensure that their build started from a clean, known good state.

All of BuildEnv L1, plus:

• Build Image Producer:

  • Build images MUST be created via a SLSA Build L3 or higher build process.
  • MUST automatically generate and distribute signed reference values for the following build image components: bootloader or equivalent, guest kernel, build agent, and root filesystem (e.g., via the image’s SLSA Provenance, or SCAI). Additional build image components whose initial state is to be checked MAY be also measured.
  • The build agent MUST be capable of:
    • Upon completion of the boot process: Automatically interfacing with the host interface to obtain and transmit a signed quote for the build environment’s system state.
    • Upon build dispatch: Automatically generating and distributing a signed attestation that binds its boot process quote to the assigned build ID (e.g., using SCAI).

• Build Platform Requirements:

  • MUST meet SLSA Build L3 requirements.
  • Prior to dispatching a tenant’s build to an instantiated environment, a signed quote MUST be automatically requested from the build agent, and the contained [measurements] verified against their boot process reference values. A signed attestation to the result of the verification MUST be generated and distributed (e.g., via a VSA).

• Compute Platform Requirements:

  • The host interface MUST be capable of generating signed quotes for the build environment’s system state. In a VM-based environment, this MUST be achieved by enabling a feature like vTPM, or equivalent, in the hypervisor. For container-based environments, the container orchestrator MAY need modifications to produce these attestations.
  • The host interface MUST validate the measurements of the build image components against their signed references values during the build environment’s boot process. In a VM-based environment, this MUST be achieved by enabling a process like Secure Boot, or equivalent, in the hypervisor. For container-based environments, the container orchestrator MAY need modifications to perform these checks.¹
  • Prior to instantiating a new build environment, the host interface MUST automatically verify the SLSA Provenance for the selected build image. A signed attestation to the verification of the build image’s SLSA Provenance MUST be automatically generated and distributed (e.g., via a VSA).

Provides evidence that a build environment deployed by a hosted build platform was instantiated from the expected build image and is at the expected initial state, even in the face of a build platform-level adversary.

The initial state of the build’s host environment is measured and authenticated by trusted hardware, attesting to the integrity of the build environment’s underlying compute stack prior to executing a build.

Organizations wanting strong assurances that their build ran on a good known host environment.

All of BuildEnv L2, plus:

• Build Image Producer:

  • Upon completion of the boot process: The build agent MUST be capable of automatically interfacing with the trusted hardware component to obtain a signed quote for the host interface’s boot process and the environment’s system state.
  • Upon build dispatch: The generated dispatch attestation MUST include the host interface’s boot process quote.

• Build Platform Requirements:

  • Prior to dispatching a tenant’s build to an instantiated environment, the measurements in the host interface’s boot process quote MUST be automatically verified against their reference values. A signed attestation to the result of the verification MUST be generated and distributed (e.g., via a VSA).

• Compute Platform Requirements:

  • MUST have trusted hardware capabilities, i.e., built-in physical hardware features for generating measurements and quotes for its system state. This SHOULD be achieved using a feature like TPM, confidential computing, or equivalent.
  • MUST enable validation of the host interface’s boot process against its reference values. This MUST be achieved by enabling a process like Secure Boot, or equivalent, in the host platform.

Provides hardware-authenticated evidence that a build ran in the expected host environment, even in the face of a compromised host interface (hypervisor/container orchestrator).