ci: make the installer verify what it installs - #298
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Closes the last unsigned step in the chain. Every release artifact has been signed since #290, but `installer` -- the path the README tells people to `curl | bash` -- still decided whether to trust a binary using `checksums.txt` alone. That file is served from the same origin as the binary and is itself unsigned, so whoever can replace one can replace the other in the same write. It detects corruption, not tampering, and presenting it as verification is worse than presenting nothing, because it reads as a check. The installer now verifies the downloaded binary against that release's `.sigstore.json`, pinning the exact identity `attest.yml@refs/tags/<VERSION>` -- the workflow and the tag, so a branch build cannot satisfy it. It fails closed. A missing bundle, an unobtainable cosign, or a signature that does not verify all stop the install. None of them falls back to the checksum: a silent downgrade to a check that proves nothing is the failure this epic exists to remove. `--skip-verify` is the only way past, it is long-form on purpose, and it is never inferred from a missing tool. cosign is used if present and otherwise fetched from a pinned version and checked against a digest embedded here. Pinning the version alone would leave the bytes to whatever that tag serves today; verifying a release with an unverified verifier proves nothing. What this cannot do is authenticate `installer` itself -- under `curl | bash` the script runs before anything checks it, and an adversary who can replace that asset can delete these lines and the pinned digest with them. SECURITY.md and README now say so plainly and document the download-verify-run path, per ADR-074. Exercised end to end against v0.2.0-rc.1, the first release carrying bundles: a signed release verifies and installs; a release with no bundles refuses; the same release installs under --skip-verify; a wrong identity refuses and installs nothing; and with cosign, gh and any token removed from the environment the bootstrap fetches cosign, matches the pinned digest, and verifies. TestInstallerVerifiesOrRefuses extracts the decision from the script and runs it against stubs over all six branches. Mutation-verified: replacing the verification failure with a checksum fallback fails it. Signed-off-by: Mark Chmarny <mark@chmarny.com>
Five persona screens on the previous commit. Two of the tests it added did not protect what they claimed. `TestInstallerSkipVerifyIsExplicit` could not fail. It looked for `SKIP_VERIFY=true` followed by a newline; the real line ends `SKIP_VERIFY=true ;;`, so the first half of the condition was never true and the check was dead. Injecting the exact defect it described -- inferring a skip from a missing cosign -- passed. It is replaced by an assertion over every SKIP_VERIFY assignment in the file, and the getopts optstring is now parsed rather than matched against a few guessed spellings. The cosign stub ignored its arguments, so the flags that *are* the verification went unchecked. Swapping `--certificate-identity` for `--certificate-identity-regexp`, or dropping `--type`, passed all six cases. Both are real weakenings: an identity naming no workflow and no ref also accepts a branch build, which is the hole this epic exists to close. The stub now records its arguments and the success case asserts on them. Nothing ran the actual `--skip-verify` parsing -- the harness set SKIP_VERIFY directly -- so deleting the case arm left a flag that was documented in usage text and error messages and wired to nothing. TestInstallerSkipVerifyFlagIsWired runs the real parsing over five argument forms. All five mutations are now caught; before this commit none of them were. Two diagnostic defects, both of which reported a local problem as tampering: `chmod +x` was unguarded and succeeds on a noexec mount, so an unrunnable cosign surfaced later as a failed signature; and cosign's output was discarded, so a Rekor outage and a genuine mismatch read identically. cosign's output is now printed and the bootstrap proves the binary runs before returning it. `fetchReleaseAsset` reported success for an empty 200 body on its two curl branches, which reached cosign and was reported as a signature failure rather than a download problem. Docs: the cutover is `v0.2.0-rc.1`, not `v0.2.0` -- rc.1 sorts *before* v0.2.0, so the old wording told users a release that verifies cleanly carries no bundles. RELEASE.md still taught checksum-only verification with no caveat, contradicting SECURITY.md's own "verify the bundle, not the checksum"; it now shows the cosign flow and says what the checksum is for. Two troubleshooting entries added for the new refusals. Signed-off-by: Mark Chmarny <mark@chmarny.com>
lalitadithya
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📝 WalkthroughWalkthroughThe installer now retrieves Sigstore bundles and verifies release binaries with pinned Cosign identities and issuer constraints. It fails closed when verification fails unless Estimated code review effort: 4 (Complex) | ~45 minutes Merge Risk: 🟡 Moderate · up to The installer adds fail-closed Sigstore verification for downloaded binaries, but its new verification-policy test suite cannot run because the extracted shell block is syntactically incomplete. This leaves the intended verification behavior unvalidated and should be fixed before merge. 🚥 Pre-merge checks | ✅ 5✅ Passed checks (5 passed)
Full details: Docstring CoverageExplanation Docstring coverage is 83.33% which is sufficient. The required threshold is 80.00%. Docstring coverage is scoped to functions touched by this diff. Analyzed 6 functions across 1 files. (4 skipped: 4 unsupported.) ✨ Finishing Touches📝 Generate docstrings
🧪 Generate unit tests (beta)
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In `@test/releasepolicy/installer_verify_test.go`:
- Around line 55-56: Update the block extraction logic around the lines loop and
its strings.Join return to track nested if/fi depth, returning only when the
outer verification branch is closed; do not stop at the inner fi for
fetchReleaseAsset, and ensure the extracted script retains the matching closing
fi so bash -n succeeds.
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…action pin Self-review, second round. Three findings were reproduced against the real release rather than argued, and one was a hallucinated commit hash. The page asserted that from v0.2.0-rc.1 onward the installer verifies what it downloads. It does not. That release was cut from 934f472, and the installer verification merged later in 991b914 (#298) -- `git merge-base --is-ancestor` confirms rc.1 predates it. The installer published with the release this page uses as its worked example checks only checksums.txt. The same overstatement was in README.md and SECURITY.md; all three now say when the behaviour actually arrives. The "confirm the commit" step could never succeed. Release tags here are signed, so `git ls-remote refs/tags/<TAG>` returns the tag object -- ee36e70 for v0.2.0-rc.1 -- while the provenance names the commit, 934f472. A reader following the one step that lets them tie the artifact to the source would have seen a mismatch on every correct release. It now peels with `^{}`, which returns 934f472 and matches, and uses --exit-code so a missing tag fails instead of printing nothing successfully. Two troubleshooting entries quoted error text cosign v3.1.3 does not emit. The real messages are `none of the attestations matched the predicate type: ..., found: ...` for a type mismatch, and a curl 404 followed by `reading <file>: no such file or directory` for a release with no bundles. Both reproduced and quoted verbatim. Nothing told the reader to set TAG to the release they actually have. Pointed at a different release these commands report success while proving nothing about the file on disk -- the same "falsely verified" failure ADR-074 names, moved from the identity to the tag. The CI gate could never have run: `imjasonh/setup-crane` was pinned to 31b88efe...9b87d81, which does not exist. The real v0.4 commit ends 9435f6e. Rather than correct the digits, this drops the third-party action and installs crane the way attest.yml already does -- direct download from the publishing project with a pinned sha256 -- which also removes the unpinned `latest-release` default it would have used. The prerequisites table now says v0.20.6, the version the pipeline actually pins, instead of a v0.21.1 that appears nowhere. The gate's rewrites were silent on failure. A TAG line gaining a trailing comment would have left it verifying the hardcoded old release forever while staying green, and a whitespace change would have re-enabled commands it is meant to skip. All three now use re.subn and fail loudly; verified by adding a trailing comment to a copy and watching it abort. Also corrected: the page claimed `set -o pipefail` plus a deferred `mv` makes the extraction failure visible. The left side of `&&` is exempt from errexit, so it did not. Split into two statements, where pipefail does abort. All 13 published blocks re-run against v0.2.0-rc.1: no failures, and the peeled ref now returns the same commit the provenance reports. Signed-off-by: Mark Chmarny <mark@chmarny.com>
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#299) * docs: publish how to verify a release, and test that the commands work Everything this epic produces is invisible to users unless we tell them the commands. Until now the only guidance was SECURITY.md, and the version of it that shipped before #286 told people to pass `--certificate-identity-regexp='https://github.com/NVIDIA/cluster-readiness-engine'` -- a pattern naming no workflow and no ref, which this repository's own `main-<sha>` development images satisfy. Following our documentation exactly accepted an unreleased branch build as a release. A verification instruction that is subtly wrong is worse than none, because it turns an unverified install into one the reader believes was verified. Adds docs/operations/verifying-artifacts.md, in the Fern nav under Operations. It leads with the verified install path -- download `installer`, check its bundle with a cosign the operator already trusts, then run it -- because the script cannot authenticate its own bytes and `curl | bash` buys TLS integrity and nothing else. Then the identity contract and why it is exact, the image (index carries provenance, per-platform manifests carry SBOMs, and why that asymmetry is not stylistic), the chart verified by digest before `helm pull`, binaries and their three differently-named bundles, reading the provenance predicate field by field, air-gapped verification, and troubleshooting. Every command was executed verbatim against v0.2.0-rc.1, in sequence, in one shell, as a reader would: eleven blocks, no failures, provenance resolving to 934f472 and the extracted SBOM carrying 1046 components. Two things the page teaches that are easy to get wrong and were found by running it. `.payload` can return several lines, because a retried signing attempt leaves more than one valid attestation and that is not tampering -- piping all of them to `base64 -d` produces nonsense. And an extract-to-file example must not redirect straight at its target: `>` truncates before the producer runs and `jq` exits 0 on empty input, so a failed verification leaves a zero-length file and a zero exit status. Enforcement, because docs that drift are the failure mode here. test/docspolicy parses every published block, requires an exact identity and a pinned issuer, and requires the page to be in the nav. .github/workflows/docs-verify.yml extracts the same blocks and runs them against the newest release weekly and on change, substituting the published tag so it fails when the pipeline drifts from the documentation rather than only when the documentation changes. All three static checks are mutation-verified. TestPublishedVerifyCommandsAreExact now walks docs/ as well. A regexp identity in a docs page is worth exactly as much to a reader as one in SECURITY.md. deployment.md's "Image provenance" row pointed at nothing; there is provenance now, so it points at it. Signed-off-by: Mark Chmarny <mark@chmarny.com> * docs: pin the whole identity, and parse the nav instead of grepping it Self-review found both new checks weaker than their names. TestVerificationPagePinsAnExactIdentity checked only the suffix `/.github/workflows/attest.yml@refs/tags/`. Replacing the repository in every published command with another one -- an identity under which cosign would verify an artifact NVIDIA never built -- passed. The suffix is the part that looks security-relevant; the origin is the part that is. It now requires the whole string, repository included. TestVerificationPageIsInTheNav did a substring match on the raw file, so a commented-out entry satisfied it while the site rendered without the page. That is precisely the "page nobody can find" state the test exists to catch. It now parses docs/index.yml and walks the navigation for a real `path` entry. Both mutation-verified: swapping the repository and commenting out the nav entry each failed exactly one test, and neither did before this commit. Signed-off-by: Mark Chmarny <mark@chmarny.com> * docs: verify the SBOM you read, and make the air-gap path actually work Self-review found four defects in the page and one in its CI gate, three of them reproduced against the real release rather than argued. The page listed three bundles per binary, said "two", fetched two, and then told readers to `jq` the SBOM file none of them authenticates. Steps 1 and 2 both take the *binary* as their subject, so replacing the local `.cyclonedx.json` with a doctored one leaves both reporting `Verified OK` while the reader's scanner ingests whatever was substituted. The third bundle, whose subject is the file, is what catches it -- confirmed by tampering with a real downloaded SBOM and watching only that check fail. It is now step 3, and "Reading the SBOM" says to do it first. The air-gapped section did not work. `cosign initialize` plus copying `~/.sigstore` fails on cosign v3.1.3, which attempts a TUF refresh on every verification and does not fall back to that cache -- it fails closed with `tuf refresh failed`, so the section was not dangerous, just wrong. The working mechanism is `--trusted-root` pointing at the exported `trusted_root.json`, verified here against the real release. The provenance block swallowed its own failure: `2>/dev/null` with pipefail but no `set -e` left STATEMENT empty, and `jq <<< ""` prints nothing and exits 0. The page fixes exactly this hazard two sections later and had not fixed it here. `head -1` was presented as safe on its own. It is what makes the command runnable when a retry left several attestations; comparing the reported commit against the tag is what makes taking the first one safe. The `git ls-remote` step is now marked as not optional. The CI gate had the same class of bug it exists to catch. Its `helm install` skip matched `.*?\n\n`, which requires a trailing blank line -- when the install is last in a block there is none, the substitution silently missed, and the extractor ran a real `helm install` against whatever kubeconfig it had. Found by running it locally, where it reached an actual EKS cluster. Now anchored to the command and its continuations. Also from review: the chart could not do what deployment.md told operators to do. `image:` was a hardcoded `repository:tag` join with no digest support, so "pin by the digest you verified" was unachievable. Adds `manager.image.digest`, which wins over `tag`, with TestHelmTemplatePinsImageByDigest covering all three combinations. The page now shows the install step that was missing entirely -- verifying a chart and then installing it by tag discards the verification -- and cross-references deployment.md for the air-gapped registry override, without which a verified artifact is deployed as an unreachable reference. All 13 published blocks re-run against v0.2.0-rc.1 in sequence: no failures, five Verified OK, SBOM extraction still yielding 1046 components. Signed-off-by: Mark Chmarny <mark@chmarny.com> * docs: correct four claims that were not true, including a fabricated action pin Self-review, second round. Three findings were reproduced against the real release rather than argued, and one was a hallucinated commit hash. The page asserted that from v0.2.0-rc.1 onward the installer verifies what it downloads. It does not. That release was cut from 934f472, and the installer verification merged later in 991b914 (#298) -- `git merge-base --is-ancestor` confirms rc.1 predates it. The installer published with the release this page uses as its worked example checks only checksums.txt. The same overstatement was in README.md and SECURITY.md; all three now say when the behaviour actually arrives. The "confirm the commit" step could never succeed. Release tags here are signed, so `git ls-remote refs/tags/<TAG>` returns the tag object -- ee36e70 for v0.2.0-rc.1 -- while the provenance names the commit, 934f472. A reader following the one step that lets them tie the artifact to the source would have seen a mismatch on every correct release. It now peels with `^{}`, which returns 934f472 and matches, and uses --exit-code so a missing tag fails instead of printing nothing successfully. Two troubleshooting entries quoted error text cosign v3.1.3 does not emit. The real messages are `none of the attestations matched the predicate type: ..., found: ...` for a type mismatch, and a curl 404 followed by `reading <file>: no such file or directory` for a release with no bundles. Both reproduced and quoted verbatim. Nothing told the reader to set TAG to the release they actually have. Pointed at a different release these commands report success while proving nothing about the file on disk -- the same "falsely verified" failure ADR-074 names, moved from the identity to the tag. The CI gate could never have run: `imjasonh/setup-crane` was pinned to 31b88efe...9b87d81, which does not exist. The real v0.4 commit ends 9435f6e. Rather than correct the digits, this drops the third-party action and installs crane the way attest.yml already does -- direct download from the publishing project with a pinned sha256 -- which also removes the unpinned `latest-release` default it would have used. The prerequisites table now says v0.20.6, the version the pipeline actually pins, instead of a v0.21.1 that appears nowhere. The gate's rewrites were silent on failure. A TAG line gaining a trailing comment would have left it verifying the hardcoded old release forever while staying green, and a whitespace change would have re-enabled commands it is meant to skip. All three now use re.subn and fail loudly; verified by adding a trailing comment to a copy and watching it abort. Also corrected: the page claimed `set -o pipefail` plus a deferred `mv` makes the extraction failure visible. The left side of `&&` is exempt from errexit, so it did not. Split into two statements, where pipefail does abort. All 13 published blocks re-run against v0.2.0-rc.1: no failures, and the peeled ref now returns the same commit the provenance reports. Signed-off-by: Mark Chmarny <mark@chmarny.com> * ci: validate the tag before interpolating it, and check each command not the page Two findings from review, both valid. docs-verify.yml interpolates a release tag into a generated shell script, and git accepts `$( )`, backticks, `;` and `&` inside a tag name -- confirmed with `git check-ref-format`, which accepts `refs/tags/v1.0$(id)`, `refs/tags/\`id\``, `refs/tags/foo;id` and `refs/tags/a&b`. The generated `TAG=v1.0$(id)` then runs the substitution. release.yml already refuses to release from anything that is not vMAJOR.MINOR.PATCH[-prerelease], but a release created through the API or the UI never passes through that check, and this workflow reads whatever exists. It now applies the same guard before using the value. The tag is also substituted through a lambda rather than an f-string, since re.sub treats backslashes in a replacement specially. TestVerificationPagePinsAnExactIdentity checked substrings across the whole page, so it passed as soon as one command somewhere pinned the identity. A second `cosign verify` with no constraints at all would have shipped undetected -- and an unconstrained command is precisely the one a reader copies. It now parses each `cosign verify*` invocation, joins its backslash continuations, and requires both the identity and the issuer on every one. Mutation-verified: adding a bare `cosign verify "${IMAGE}:${TAG}"` to the page now fails with the offending command quoted, and the tag guard refuses `v1.0$(id)` and `foo;id` while accepting `v1.2.3` and `v1.2.3-rc.1`. Signed-off-by: Mark Chmarny <mark@chmarny.com> --------- Signed-off-by: Mark Chmarny <mark@chmarny.com>
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Summary
Closes the last unsigned step in the chain. Every release artifact has been signed since #290, but
installer— the path the README tells people tocurl | bash— still decided whether to trust a binary usingchecksums.txtalone. That file is served from the same origin as the binary and is itself unsigned, so whoever can replace one can replace the other in the same write. It detects corruption, not tampering, and presenting it as verification is worse than presenting nothing, because it reads as a check.The installer now verifies the downloaded binary against that release's
.sigstore.json, pinning the exact identityattest.yml@refs/tags/<VERSION>— the workflow and the tag, so a branch build cannot satisfy it.It fails closed. A missing bundle, an unobtainable cosign, or a signature that does not verify all stop the install. None falls back to the checksum.
--skip-verifyis the only way past, it is long-form on purpose, and it is never inferred from a missing tool or a failed download.cosign is used if present and otherwise fetched from a pinned version and checked against a digest embedded in the script. Pinning the version alone would leave the bytes to whatever that tag serves today — verifying a release with an unverified verifier proves nothing.
What this deliberately does not do
installercannot authenticate its own bytes. Undercurl … | bashthe script executes before anything has checked it, and an adversary who could replace that asset could delete the verification logic and its pinned digest in the same write.SECURITY.mdandREADME.mdnow say so plainly and document the download-verify-run path, per ADR-074's Consequences.Related Issue
Part of #268 — the "installer's own fail-closed verification, cosign bootstrap and
--skip-verify" criterion, which the epic deferred until bundles existed to test against. They exist now:v0.2.0-rc.1.Type of Change
Component(s) Affected
Testing
Exercised end to end against
v0.2.0-rc.1, the first release carrying bundles:v0.1.0)--skip-verifyand why--skip-verifygh, no tokenThat last row is the bare-machine case ADR-074 calls for, and it exercises the anonymous download path too.
TestInstallerVerifiesOrRefusesextracts the decision from the script and runs it against stubs over all six branches.TestInstallerSkipVerifyFlagIsWiredruns the real argument parsing.TestInstallerSkipVerifyIsNeverInferredasserts over everySKIP_VERIFYassignment.v0.2.0-rc.1now require--skip-verify, which is the intended behaviour changeSelf-review
Five persona screens. The second commit fixes what they found, and two of those findings were that the tests in the first commit did not protect what they claimed.
TestInstallerSkipVerifyIsExplicitcould not fail. It searched forSKIP_VERIFY=truefollowed by a newline; the real line endsSKIP_VERIFY=true ;;, so the condition was never true. Injecting the exact defect it described — inferring a skip from a missing cosign — passed.The cosign stub ignored its arguments, so the flags that are the verification went unchecked. Swapping
--certificate-identityfor--certificate-identity-regexp, or dropping--type, passed all six cases.Nothing ran the actual
--skip-verifyparsing, so deleting the case arm left a flag documented everywhere and wired to nothing.Mutation results, before and after:
--skip-verifycase arm gutted--typedropped-sflag addedAlso fixed:
chmod +xwas unguarded and succeeds on anoexecmount, so an unrunnable cosign surfaced later as a failed signature; cosign's output was discarded, so a Rekor outage and a genuine mismatch read identically; andfetchReleaseAssetreported success for an empty 200 body, which then reached cosign and was reported as tampering. All three turned local problems into supply-chain-shaped alarms, which is how a check earns a reputation for crying wolf.Docs findings: the cutover is
v0.2.0-rc.1, notv0.2.0— rc.1 sorts before v0.2.0 under SemVer, so the original wording told users a release that verifies cleanly carries no bundles.RELEASE.mdstill taught checksum-only verification with no caveat, contradictingSECURITY.md's own "verify the bundle, not the checksum".Known gap, stated rather than papered over
fetchReleaseAssetandresolveCosignhave no automated coverage. They were exercised by hand against a real release, which is not the same thing and will not catch a regression in the asset-name escaping or the bootstrap digest check. The test comment says so. Closing it needs a local asset server or a live-release job, and is worth doing.Checklist
git commit -s)make manifests generaterun (if*_types.gowas modified) — n/aREADME.md,SECURITY.md,RELEASE.md