The pre-G-1 config validator accepted CERTCTL_AUTH_TYPE=jwt and the
startup log faithfully echoed 'authentication enabled type=jwt'.
Reasonable people read that and concluded JWT auth was on. It wasn't.
The auth-middleware wiring at cmd/server/main.go unconditionally routed
every request through the api-key bearer middleware regardless of
cfg.Auth.Type. So CERTCTL_AUTH_TYPE=jwt quietly compared the incoming
'Authorization: Bearer <token>' against whatever string the operator put
in CERTCTL_AUTH_SECRET — real JWT clients got 401, and operators who
treated CERTCTL_AUTH_SECRET as a *signing* secret (because they thought
they were configuring JWT) had effectively handed an attacker an api-key.
A security finding masquerading as a config option.
We chose the audit-recommended structural fix: remove the option, fail
fast at startup, and add the gateway-fronting pattern as the documented
forward path. Implementing JWT middleware would have meant jwks vs
static-secret rotation, claim mapping, expiry enforcement, audience and
issuer validation, key rollover semantics, and regression coverage at the
same depth as the existing api-key path — a feature, not a fix. Operators
who genuinely need JWT/OIDC front certctl with an authenticating gateway
(oauth2-proxy / Envoy ext_authz / Traefik ForwardAuth / Pomerium /
Authelia) and run the upstream certctl with CERTCTL_AUTH_TYPE=none. Same
shape works on docker-compose and Helm.
The change is comprehensive across 7 phases — every surface that
mentioned 'jwt' as a certctl-auth-type is updated, plus structural
backstops (typed enum, runtime guard, helm template validation, CI grep
guard) so the lie can't reappear.
Files changed:
Phase 1 — production code (typed enum + jwt removal):
- internal/config/config.go: AuthType typed alias + AuthTypeAPIKey /
AuthTypeNone constants + ValidAuthTypes() helper. Validate() routes
literal 'jwt' through a dedicated multi-line diagnostic naming the
authenticating-gateway pattern, then cross-checks against
ValidAuthTypes(). Secret-required branch simplified to api-key-only.
Field comment on AuthConfig.Type rewritten to drop jwt and point at
the gateway pattern.
- internal/api/middleware/middleware.go: AuthConfig.Type field comment
references the typed config.AuthType constants.
- internal/api/handler/health.go: same treatment for HealthHandler.AuthType.
- cmd/server/main.go: defense-in-depth runtime switch immediately after
config.Load() — exits 1 on any unsupported auth-type that bypassed the
validator. Auth-disabled startup log explicitly names the
authenticating-gateway pattern.
Phase 2 — tests (Red→Green, contract pinning):
- internal/config/config_test.go: TestValidate_JWTAuth_RejectedDedicated
(two table rows pinning the dedicated G-1 error fires regardless of
whether Secret is set), TestValidAuthTypesDoesNotContainJWT (property
guard against future re-introduction),
TestValidAuthTypesIsExactly_APIKey_None (allowed-set contract),
TestValidate_GenericInvalidAuthType (pins non-jwt invalid values still
hit the generic invalid-auth-type error). Removed the prior
TestValidate_JWTAuth_MissingSecret happy-path since its premise is
inverted post-G-1.
- internal/api/handler/health_test.go: removed
TestAuthInfo_ReturnsAuthType_JWT (which baked the silent-downgrade lie
into the regression suite). Pre-existing _APIKey test continues to
cover the api-key happy path.
Phase 3 — spec, docs, env templates:
- api/openapi.yaml: auth_type enum dropped to [api-key, none] with
inline comment naming the G-1 closure.
- .env.example (root): CERTCTL_AUTH_TYPE comment block rewritten to drop
jwt and point at the gateway pattern; secret-required conditional
simplified to api-key-only.
- docs/architecture.md: middleware-stack bullet rewritten to drop the
JWT mention; new H3 'Authenticating-gateway pattern (JWT, OIDC, mTLS)'
section explaining the design rationale and listing oauth2-proxy /
Envoy ext_authz / Traefik ForwardAuth / Pomerium / Authelia / Caddy
forward_auth / Apache mod_auth_openidc / nginx auth_request as the
standard fronting options.
- docs/upgrade-to-v2-jwt-removal.md (new ~125 lines): migration guide
with preconditions, what-changes, both recovery paths, complete
docker-compose oauth2-proxy walkthrough, Traefik ForwardAuth and Envoy
ext_authz patterns, rollback posture.
Phase 4 — Helm chart (template validation + docs):
- deploy/helm/certctl/templates/_helpers.tpl: new certctl.validateAuthType
helper mirroring the existing certctl.tls.required pattern. Fails
template render on any server.auth.type outside {api-key, none} with
a multi-line diagnostic.
- deploy/helm/certctl/templates/server-deployment.yaml,
server-configmap.yaml, server-secret.yaml: invoke the helper at the
top of each template that depends on .Values.server.auth.type.
- deploy/helm/certctl/values.yaml: auth: block comment expanded with the
G-1 rationale and gateway-pattern cross-reference.
- deploy/helm/CHART_SUMMARY.md: server.auth.type table row now surfaces
the allowed set and points at the upgrade doc.
- deploy/helm/certctl/README.md: new 'JWT / OIDC via authenticating
gateway' section with a Kubernetes-flavored oauth2-proxy + certctl
walkthrough.
Phase 5 — release surface:
- CHANGELOG.md: new [unreleased] top entry with Breaking / Removed /
Added / Changed sections; explicit pointer at
docs/upgrade-to-v2-jwt-removal.md from the Breaking subsection.
Phase 6 — CI guardrail:
- .github/workflows/ci.yml: new 'Forbidden auth-type literal regression
guard (G-1)' step. Scoped patterns catch the actual regression shapes
(map literal, slice literal, switch case, OpenAPI enum, env-file
default, AuthType('jwt') cast). Comments and the dedicated rejection
branch are intentionally exempt; connector-package JWT references
(Google OAuth2 / step-ca) are exempt as out-of-scope external
protocols. Verified locally: the guard passes on the actual tree and
fires on all 4 synthetic regression patterns.
Out of scope (explicitly untouched):
- internal/connector/discovery/gcpsm/gcpsm.go — Google OAuth2 service-
account JWT (external protocol).
- internal/connector/issuer/googlecas/googlecas.go — same.
- internal/connector/issuer/stepca/stepca.go — step-ca's provisioner
one-time-token JWT for /sign API.
- docs/test-env.md, docs/connectors.md, docs/features.md — describe
external CAs' use of JWT, not certctl's auth shape.
- Implementing actual JWT middleware. Feature, not a fix.
Verification (all gates pass):
- go build ./... — clean
- go vet ./... — clean
- go test -short ./... — every package green
- go test -short -race ./internal/config/... ./internal/api/... — clean
- govulncheck ./... — no vulnerabilities in our code
- helm lint deploy/helm/certctl/ — clean
- helm template with auth.type=api-key — renders OK
- helm template with auth.type=none — renders OK
- helm template with auth.type=jwt — fails with validateAuthType
diagnostic (exit 1)
- python3 yaml.safe_load on api/openapi.yaml — parses
- CI guardrail mirror — clean on real tree, fires on all 4 synthetic
regression patterns
- Smoke test: 'CERTCTL_AUTH_TYPE=jwt ./certctl-server' exits non-zero
with: 'Failed to load configuration: CERTCTL_AUTH_TYPE=jwt is no
longer accepted (G-1 silent auth downgrade): no JWT middleware ships
with certctl. To use JWT/OIDC, run an authenticating gateway
(oauth2-proxy / Envoy ext_authz / Traefik ForwardAuth / Pomerium) in
front of certctl and set CERTCTL_AUTH_TYPE=none on the upstream.
See docs/architecture.md "Authenticating-gateway pattern" and
docs/upgrade-to-v2-jwt-removal.md for the migration walkthrough'
config pkg coverage: ValidAuthTypes 100%, Validate 94.7%, total 75.5%.
Refs: coverage-gap-audit-2026-04-24-v5/unified-audit.md
§2 P1 cluster, cat-g-jwt_silent_auth_downgrade
Audit recommendation followed verbatim: 'Remove jwt from
validAuthTypes until middleware ships'.
8.0 KiB
certctl Helm Chart
Production-ready Helm chart for deploying certctl on Kubernetes. Wires up the certctl server (Deployment), PostgreSQL (StatefulSet with PVC), and the agent (DaemonSet — one per node) on a private cluster, with health probes, security contexts, and optional Ingress.
Quick install
helm install certctl deploy/helm/certctl/ \
--create-namespace --namespace certctl \
--set server.auth.apiKey="$(openssl rand -base64 32)" \
--set postgresql.auth.password="$(openssl rand -base64 24)"
This brings up:
<release>-serverDeployment (HTTPS-only on port 8443; TLS 1.3)<release>-postgresStatefulSet (PostgreSQL 16-alpine, 1 replica, 10Gi PVC by default)<release>-agentDaemonSet (polls server, generates ECDSA P-256 keys locally)- Service objects, optional Ingress, and ServiceAccount with RBAC
See values.yaml for the full configuration surface — issuer settings, target connectors, scheduler intervals, notifier credentials, and resource requests/limits all live there.
Operational notes
Postgres password rotation — read this before changing postgresql.auth.password
The trap. postgresql.auth.password is bound to pg_authid exactly once — when the StatefulSet's PVC is provisioned and initdb runs. The official postgres:16-alpine image only runs initdb when /var/lib/postgresql/data is empty, so on every subsequent rollout the POSTGRES_PASSWORD env var is read into the container but ignored by postgres itself. The certctl-server container also picks up the new value (via the database URL helper template), so the two halves diverge: server presents the new password, postgres still expects the old one.
Symptom. The certctl-server pod's startup log shows:
failed to ping database: postgres rejected the configured credentials
(SQLSTATE 28P01 — invalid_password). If you recently rotated POSTGRES_PASSWORD ...
That diagnostic is emitted by internal/repository/postgres/db.go::wrapPingError — it points operators at the two remediation paths below.
Remediation, non-destructive (preferred for any environment with real data):
# 1. Rotate the password in postgres directly
kubectl -n certctl exec -it <release>-postgres-0 -- \
psql -U certctl -c "ALTER ROLE certctl PASSWORD '<new-password>';"
# 2. Update the secret / Helm values to the same value
helm upgrade <release> deploy/helm/certctl/ \
--reuse-values \
--set postgresql.auth.password='<new-password>'
# 3. Bounce the certctl-server pod so it re-reads the secret
kubectl -n certctl rollout restart deployment/<release>-server
Remediation, destructive (DESTROYS ALL CERTCTL DATA — only acceptable on dev/demo clusters):
helm uninstall <release> -n certctl
kubectl -n certctl delete pvc -l \
app.kubernetes.io/name=certctl,app.kubernetes.io/component=postgres
helm install <release> deploy/helm/certctl/ \
--namespace certctl \
--set postgresql.auth.password='<new-password>'
The PVC re-creates empty, initdb runs on first boot of the new postgres pod, and pg_authid is seeded with the new password.
Why we don't fix this in the chart. The env-vs-pg_authid divergence is intrinsic to how the upstream postgres image bootstraps — initdb is run-once-per-empty-data-dir, and there is no upstream-supported way to make subsequent boots re-seed pg_authid from POSTGRES_PASSWORD. The ergonomic answer is the runtime diagnostic plus this operational note.
Cross-references. Same root cause is documented for the docker-compose path in docs/quickstart.md (Warning callout after the cp .env.example .env block) and in deploy/ENVIRONMENTS.md (Stateful volume — first-boot password binding section). The runtime diagnostic itself lives in internal/repository/postgres/db.go::wrapPingError with regression coverage in internal/repository/postgres/db_test.go.
Server API key rotation
Unlike the postgres password, server.auth.apiKey accepts a comma-separated list, so zero-downtime rotation is straightforward:
# 1. Add the new key alongside the old
helm upgrade <release> deploy/helm/certctl/ \
--reuse-values \
--set server.auth.apiKey='new-key,old-key'
# 2. Roll your agents / clients over to the new key
# 3. Remove the old key
helm upgrade <release> deploy/helm/certctl/ \
--reuse-values \
--set server.auth.apiKey='new-key'
JWT / OIDC via authenticating gateway
certctl's in-process auth surface is intentionally narrow: server.auth.type=api-key for production deployments and server.auth.type=none for development. There is no in-process JWT, OIDC, mTLS, or SAML middleware. (server.auth.type=jwt was accepted pre-G-1 but silently routed every request through the api-key bearer middleware — silent auth downgrade. The chart now fails at helm install/helm upgrade template time via the certctl.validateAuthType helper if you set it. See ../../../docs/upgrade-to-v2-jwt-removal.md if you previously had this in your values.)
For deployments that need JWT/OIDC, the canonical Kubernetes-flavored shape is to put oauth2-proxy in front of the certctl Service, attach an authenticating Ingress middleware, and run certctl with server.auth.type=none:
# 1. Install oauth2-proxy (or any OIDC-terminating sidecar) in the same namespace
helm install oauth2-proxy oauth2-proxy/oauth2-proxy \
--namespace certctl \
--set config.clientID="$OIDC_CLIENT_ID" \
--set config.clientSecret="$OIDC_CLIENT_SECRET" \
--set config.cookieSecret="$(openssl rand -base64 32)" \
--set config.configFile='|
provider = "oidc"
oidc_issuer_url = "https://your-issuer/"
upstreams = ["http://<release>-server.certctl.svc.cluster.local:8443"]
pass_authorization_header = true
set_authorization_header = true
email_domains = ["*"]
'
# 2. Install certctl with type=none (gateway terminates auth)
helm install certctl deploy/helm/certctl/ \
--namespace certctl \
--set server.auth.type=none \
--set postgresql.auth.password="$(openssl rand -base64 24)"
# 3. Attach an Ingress that routes through oauth2-proxy
# (Traefik ForwardAuth, nginx auth_request, Envoy ext_authz, etc.)
Same root pattern works with Pomerium, Authelia, Caddy forward_auth, Apache mod_auth_openidc, or any service-mesh ext_authz. See ../../../docs/architecture.md "Authenticating-gateway pattern" for the full design rationale and ../../../docs/upgrade-to-v2-jwt-removal.md for the migration walkthrough.
TLS certificate sourcing
By default the chart provisions a self-signed cert via the same init-container pattern as the docker-compose deploy. For production, supply an operator-managed Secret (cert-manager, internal CA, etc.) — see docs/tls.md for the full provisioning matrix and docs/upgrade-to-tls.md for upgrade-from-HTTP procedures.
Disabling embedded postgres
If you have an existing PostgreSQL cluster, disable the embedded one and point at it directly:
helm install certctl deploy/helm/certctl/ \
--set postgresql.enabled=false \
--set server.databaseUrl='postgres://certctl:<pw>@my-pg-host:5432/certctl?sslmode=require'
The volume-trap section above does not apply to this configuration — your postgres operator (or cloud DB) handles password rotation, and you control pg_authid directly.
Uninstall
helm uninstall <release> -n certctl
# Optional — also delete the postgres PVC (DESTROYS DATA):
kubectl -n certctl delete pvc -l \
app.kubernetes.io/name=certctl,app.kubernetes.io/component=postgres
By default helm uninstall retains the StatefulSet's PVCs, so reinstalling with the same release name preserves the database. If you've changed postgresql.auth.password in your values between uninstall and reinstall, you'll hit the trap on the reinstall — apply the non-destructive remediation above, or also delete the PVC.