Skip to main content
Version: Next

Release verification

Since poof v0.6.3, every stable release archive has GitHub provenance and SPDX SBOM attestations. Releases also publish one build-environment JSON record per archive and a canonical aggregate checksum manifest, signed using Cosign keyless signing with GitHub Actions OIDC. Archive checksums are published in this manifest; individual .sha256 sidecars are not published.

Verify signatures and checksums​

Download the checksum manifest, its .sigstore.json bundle, and the assets you need from the same release. Use a current Cosign version (CI pins v3.1.4). For example, for v0.6.3:

cosign verify-blob poof-0.6.3-checksums.txt \
  --bundle poof-0.6.3-checksums.txt.sigstore.json \
  --certificate-identity 'https://github.com/pirafrank/poof/.github/workflows/release.yml@refs/tags/v0.6.3' \
  --certificate-oidc-issuer 'https://token.actions.githubusercontent.com'
sha256sum --check poof-0.6.3-checksums.txt

Run the checksum command from the assets directory. It requires all listed files. For a wrapper that downloads a single target, after verifying the signature, select the manifest entry by the exact expected filename and verify that archive digest. Require exactly one matching entry and reject missing entries, mismatches, and verification failures before installation. On macOS, shasum -a 256 --check can replace sha256sum --check.

The exact tag identity above prevents accepting signatures for a different release or branch. Manual workflow runs also produce signed workflow artifacts but never publish a GitHub release. Also, branch runs do not satisfy the release-tag identity shown above.

Verify GitHub attestations​

To check SLSA provenance and SPDX GitHub attestations for an archive, for example poof-0.6.3-x86_64-unknown-linux-musl.tar.gz:

gh attestation verify poof-0.6.3-x86_64-unknown-linux-musl.tar.gz \
  --repo pirafrank/poof \
  --signer-workflow pirafrank/poof/.github/workflows/release.yml \
  --source-ref refs/tags/v0.6.3
gh attestation verify poof-0.6.3-x86_64-unknown-linux-musl.tar.gz \
  --repo pirafrank/poof \
  --signer-workflow pirafrank/poof/.github/workflows/release.yml \
  --source-ref refs/tags/v0.6.3 --predicate-type https://spdx.dev/Document/v2.3

Build-environment schema version 1​

poof-<version>-<target>.build-environment.json contains artifact, source, github_actions, runner, toolchain, build, native_toolchain, cross, inputs, and captured_at sections. The artifact section identifies the finished archive by filename, SHA-256, target triple, and byte size. Its record is authenticated by the signed manifest.

The record captures:

  • GitHub Actions: An explicit allowlist of fields: repository and repository ID, workflow name/ref/SHA, run ID/attempt/number, event name, ref/name, SHA, actor, and server URL;
  • Runner: The selected matrix label, operating system, architecture, environment, kernel, OS release, and runner image version when available;
  • Rust toolchain: Verbose compiler and Cargo versions, active and installed toolchains/targets, and hashes of toolchain files;
  • Build: The exact argument vector, release profile, default, additional, and resolved features, and matrix entry;
  • Input hashes: Workspace manifests, lockfile, repository Cargo configuration, dependency metadata/tree, matrix, build script, collector, and release workflow.

The native_toolchain section describes host tools. Cross toolchain details are recorded in cross, based on probes of the resolved container image. Image references are resolved before the build, and the resulting digest is passed to Cross so it uses the image recorded in the report. No custom Dockerfile or base image is configured today, so those fields are null. If a custom Cross image is added, the collector must also record its Dockerfile and base-image digests.

Unavailable or inapplicable probes, and optional probes that fail, are represented as JSON null. Environment flags are fully redacted and, when present, accompanied by hashes. Cargo home and the target directory are recorded only as locations. Credential files, tokens, arbitrary environment variables, and the full GitHub context are never collected. Cargo configuration is hashed, not included. Dependency metadata/tree hashes describe the captured output, which may contain runner-specific paths; they do not prove that the dependency graph is reproducible.

Capture time and run identity are included for auditing. This record helps investigate builds; proving bit-for-bit reproducibility requires independent rebuilds and comparison of their output.