# Build-iso CI hardening

**Agent 8 of 9-agent wave, 2026-05-05.**

## State of play

- Workflows: `build-iso.yml`, `lint.yml`, `Release Checksums` (auto)
- Secrets/variables: **none configured** — only ambient `GITHUB_TOKEN`
- Repo: private, MIT, no Pages, no Dependabot, no branch protection
  (Pro-gated until public flip)
- Container: `registry.fedoraproject.org/fedora:43` (tag, not digest)
- Actions: `actions/checkout@v4`, `addnab/docker-run-action@v3`,
  `softprops/action-gh-release@v2`, `ludeeus/action-shellcheck@master`
  — **all unpinned to SHA**
- gum download: pinned by SHA256 ✓
- Kickstart repos: `releases/43/Everything` + `updates/43/Everything`
  — **both rolling**, byte-different daily

## Top 5 immediate (S effort, ship in v0.5.32)

| # | Item | Why |
|---|------|-----|
| 1 | Pin all actions to commit SHA + add `.github/dependabot.yml` for `github-actions` | Supply-chain — `@master` on shellcheck is live-takeover vector; v3/v4 tags are mutable |
| 2 | Pin Fedora container to digest (`registry.fedoraproject.org/fedora:43@sha256:...`) | One-line change; eliminates "container drift" repro class |
| 3 | Add `permissions:` block at workflow level (`contents: read` default), override per-job | `contents: write` is workflow-wide; least-privilege the lint job |
| 4 | Generate SBOM via `anchore/sbom-action`, attach to release | Free, ~30 lines, journalist-readable |
| 5 | Add `actions/attest-build-provenance@v2` for SLSA L3 attestation on ISO + parts | Free, GH-native, `id-token: write` only |

## v0.4 release-eng roadmap (confirmed/added)

- **Confirmed:** Sigstore/cosign signing of ISOs (already in roadmap)
- **Add:** Fedora compose-ID pinning per release tag — switch
  `--baseurl` to
  `kojipkgs.fedoraproject.org/compose/branched/Fedora-43-...n.X/compose/Everything/x86_64/os/`
  for stable releases (rolling for `ci-latest`)
- **Add:** Reproducible-Builds.org diffoscope job comparing 2
  sequential builds of same SHA — gate on byte-equality
- **Add:** `harden-runner` (StepSecurity) audit-mode pass to enumerate
  egress; promote to block-mode in v0.5
- **Add:** When repo flips public (v0.7), enable secret scanning + push
  protection + private vuln reporting + branch protection (require ≥1
  review, status checks: lint + ksvalidate + build, no force-push)
- **Add:** OIDC `id-token: write` only in tag-release job (not on
  `main` push) — keysless cosign signing scoped to release events

## YAML diffs

### 1. Workflow-level permissions + per-job override

```yaml
permissions:
  contents: read

jobs:
  build:
    permissions:
      contents: write       # gh-release
      id-token: write       # cosign keyless + attestation
      attestations: write
```

### 2. SHA-pin actions

```yaml
- uses: actions/checkout@692973e3d937129bcbf40652eb9f2f61becf3332     # v4.1.7
- uses: addnab/docker-run-action@4f65375b03d588f307b7a3b0a8bb50f8b58a85b9 # v3
- uses: softprops/action-gh-release@01570a1f39cb168c169c802c3bceb9e93fb10974 # v2.1.0
```

(SHAs to be re-checked at apply-time; dependabot keeps them current)

### 3. Pin Fedora digest

```yaml
image: registry.fedoraproject.org/fedora:43@sha256:<DIGEST>
```

Capture once via `skopeo inspect --raw
docker://registry.fedoraproject.org/fedora:43 | jq -r .config.digest`
and bump on each releasever bump.

### 4. SBOM + attestation + cosign

```yaml
- name: Install cosign
  uses: sigstore/cosign-installer@d7d6e07a3ddf0f9a4f8b3b9e3f1d1a5ce8e9b5b3 # v3.7.0

- name: Sign ISO parts (keyless)
  if: github.event_name == 'release'
  run: |
    cd build/out
    for f in *.part-*; do cosign sign-blob --yes "$f" \
      --output-signature "$f.sig" --output-certificate "$f.pem"; done

- name: Generate SBOM (SPDX)
  uses: anchore/sbom-action@e8d2a6937ecead383dfe75190d104edd1f9c5751 # v0.17.4
  with:
    path: build/out
    format: spdx-json
    output-file: build/out/veilor-os.spdx.json

- name: Build provenance attestation
  uses: actions/attest-build-provenance@7668571508540a607bdfd90a87a560489fe372eb # v2.1.0
  with:
    subject-path: 'build/out/*.part-*'
```

### 5. New `.github/dependabot.yml`

```yaml
version: 2
updates:
  - package-ecosystem: "github-actions"
    directory: "/"
    schedule: { interval: "weekly" }
    groups:
      actions: { patterns: ["*"] }
```

### 6. Timeout

Keep at 90min. Largest observed runs ~70min; trimming would
false-fail Fedora-mirror-slow days. **No change.**

## Q&A

- **Secrets in use:** none. Only ambient `GITHUB_TOKEN`. Once public,
  enable secret scanning + push protection (free for public repos).
- **Pages:** not deployed from this repo. Docs site out-of-scope here.
- **Dependency review:** only `gum` fetched out-of-band — already
  SHA256-pinned. Add `actions/dependency-review-action` on PRs once public.