gsadmin/certctl
1
0
Fork 0
mirror of https://github.com/shankar0123/certctl.git synced 2026-06-07 16:21:30 +00:00
Code Issues Packages Projects Releases Wiki Activity

fix(security,config): remove unimplemented JWT auth-type, close silent downgrade (G-1)

Browse Source 
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'.
This commit is contained in:
shankar0123
2026-04-25 00:22:23 +00:00
parent 3192cd15c5
commit 9c1d446e40
19 changed files with 629 additions and 65 deletions
Download Patch File Download Diff File Expand all files Collapse all files
docs/architecture.md
+7 -1
View File
@@ -891,9 +891,15 @@ The HTTP middleware stack processes requests in the following order (see `cmd/se
4. **BodyLimit** - request body size cap via `http.MaxBytesReader`
5. **RateLimiter** - token bucket rate limiting (optional, when enabled)
6. **CORS** - cross-origin request handling (deny-by-default)
7. **Auth** - API key or JWT validation
7. **Auth** - API key validation (or none in development; JWT/OIDC via authenticating gateway, see below — not in-process)
8. **AuditLog** - records every API call to the audit trail (requires auth context for actor)
### Authenticating-gateway pattern (JWT, OIDC, mTLS)
certctl's in-process authentication surface is intentionally narrow: `api-key` for production deployments and `none` for development. There is no in-process JWT, OIDC, mTLS, or SAML middleware. (`CERTCTL_AUTH_TYPE=jwt` was accepted pre-G-1 but silently routed through the api-key bearer middleware — a security finding masquerading as a config option, removed at the v2.x boundary; see [`upgrade-to-v2-jwt-removal.md`](upgrade-to-v2-jwt-removal.md) if you previously set it.)
For deployments that need JWT/OIDC/mTLS, the standard pattern is to put an authenticating gateway in front of certctl and configure `CERTCTL_AUTH_TYPE=none` on the upstream certctl process. The gateway terminates the federated identity protocol, validates tokens / certificates / SAML assertions, and proxies the authenticated request to certctl as a same-origin call on a private network. This separation gives operators the full breadth of the modern identity ecosystem (oauth2-proxy, Envoy `ext_authz`, Traefik `ForwardAuth`, Pomerium, Authelia, Caddy `forward_auth`, Apache `mod_auth_openidc`, nginx `auth_request`) without certctl itself having to track signing-key rotation, claim mapping, audience validation, and the rest of the JWT/OIDC surface area. Operators wanting per-request actor attribution past the gateway boundary forward the gateway-resolved identity (e.g., `X-Auth-Request-User` from oauth2-proxy) and run a small authorization layer at the gateway that enforces the bearer-key contract certctl actually uses.
### Concurrency Safety
The background scheduler uses `sync/atomic.Bool` idempotency guards on every loop (8 always-on plus up to 4 optional) — if a tick fires while the previous iteration is still running, it skips. A `sync.WaitGroup` tracks all in-flight goroutines. `WaitForCompletion(timeout)` blocks during shutdown until all work finishes or the timeout expires, preventing state corruption from mid-flight database operations during process exit.
docs/upgrade-to-v2-jwt-removal.md
+155
View File
@@ -0,0 +1,155 @@
# Upgrading past G-1 — `CERTCTL_AUTH_TYPE=jwt` removal
If your certctl deployment currently sets `CERTCTL_AUTH_TYPE=jwt` (or `server.auth.type=jwt` in Helm), the next certctl upgrade will fail-fast at startup with a dedicated diagnostic. This guide explains why, what to switch to, and how to keep JWT/OIDC at your edge.
For everyone else — operators running `api-key` or `none` — this upgrade is a no-op. Skip to [`upgrade-to-tls.md`](upgrade-to-tls.md) for the v2.2 HTTPS-everywhere migration if you haven't done that one yet.
## Why we removed it
Pre-G-1, the config validator at `internal/config/config.go` accepted three values for `CERTCTL_AUTH_TYPE`: `api-key`, `jwt`, and `none`. The startup log line at `cmd/server/main.go` faithfully echoed `"authentication enabled" "type"="jwt"` when an operator picked `jwt`. Reasonable people read that and concluded JWT auth was on.
It wasn't. Grep `internal/ cmd/` for `NewJWT`, `JWTMiddleware`, or `jwt.Parse` — pre-G-1, there were zero matches in production code. The auth-middleware wiring at `cmd/server/main.go:653` unconditionally called `middleware.NewAuthWithNamedKeys(namedKeys)` regardless of `cfg.Auth.Type`. So `CERTCTL_AUTH_TYPE=jwt` just routed every request through the api-key bearer middleware, comparing the incoming `Authorization: Bearer <something>` against whatever string the operator put in `CERTCTL_AUTH_SECRET`. Real JWT clients got 401 (the api-key middleware saw the JWT string as a literal token and compared bytes). Operators who treated `CERTCTL_AUTH_SECRET` as a JWT signing secret (and therefore handled it less carefully than an api-key) handed an attacker an api-key. Silent auth downgrade — a security finding masquerading as a config option.
We chose to remove the option rather than implement JWT middleware. Implementing real JWT/OIDC requires jwks vs static-secret rotation, claim mapping (which claim is the actor / the admin flag?), expiry enforcement, audience and issuer validation, key rollover semantics, and regression coverage at the same depth as the existing api-key path. That's a feature, not a fix. The audit-recommended structural fix — and the one that actually closes the hazard — is to fail loudly instead of silently downgrading.
## What changes at startup
Post-G-1, a binary started with `CERTCTL_AUTH_TYPE=jwt` exits non-zero before opening the listener:
```
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
```
Helm operators get the same shape at `helm install` / `helm upgrade` template time: `server.auth.type=jwt` is rejected by the chart's `certctl.validateAuthType` template helper before any Kubernetes object is rendered.
The CI-side regression guard at `.github/workflows/ci.yml` blocks any future PR that re-introduces `"jwt"` as an auth-type literal in production code or spec.
## Recovery — pick one
### Option A — switch to `api-key` (you weren't actually using JWT)
If your `CERTCTL_AUTH_SECRET` was a single high-entropy token and your clients sent it as `Authorization: Bearer <token>`, you were already using api-key auth — you just had `CERTCTL_AUTH_TYPE` set to the wrong string. Flip it:
```
# .env (docker-compose)
CERTCTL_AUTH_TYPE=api-key
CERTCTL_AUTH_SECRET=<your-existing-token>
```
```
# Helm
helm upgrade <release> deploy/helm/certctl/ \
--reuse-values \
--set server.auth.type=api-key \
--set server.auth.apiKey=<your-existing-token>
```
No client changes needed — the same Bearer token continues to work. The startup log will now read `"authentication enabled" "type"="api-key"`, which matches what was actually happening pre-G-1.
### Option B — front certctl with an authenticating gateway
If you genuinely need JWT, OIDC, mTLS, or SAML, run an authenticating gateway in front of certctl and let the gateway terminate the federated identity protocol. Configure certctl for `CERTCTL_AUTH_TYPE=none`:
```
CERTCTL_AUTH_TYPE=none
```
Then put an oauth2-proxy / Envoy `ext_authz` / Traefik `ForwardAuth` / Pomerium / Authelia (etc.) in the network path between operators and certctl. The gateway validates the identity and proxies the authenticated request to certctl as a same-origin call on a private network.
### Concrete walkthrough — oauth2-proxy + certctl on docker-compose
This is the simplest production-grade JWT/OIDC shape. It assumes you have an OIDC provider (Okta, Auth0, Google Workspace, Keycloak, Dex) and a registered client_id / client_secret.
```yaml
# deploy/docker-compose.gateway.yml — overlay on the base compose file
services:
oauth2-proxy:
image: quay.io/oauth2-proxy/oauth2-proxy:latest
command:
- --provider=oidc
- --oidc-issuer-url=https://<your-issuer>/
- --client-id=${OIDC_CLIENT_ID}
- --client-secret=${OIDC_CLIENT_SECRET}
- --cookie-secret=${OAUTH2_PROXY_COOKIE_SECRET} # openssl rand -base64 32
- --upstream=http://certctl-server:8443 # internal-network only; certctl listens on 8443
- --http-address=0.0.0.0:4180
- --email-domain=*
- --pass-access-token=true
- --pass-authorization-header=true
- --set-authorization-header=true # forwards a bearer token upstream
- --skip-provider-button=true
- --reverse-proxy=true
ports:
- "443:4180"
depends_on:
- certctl-server
networks:
- certctl-network
certctl-server:
environment:
CERTCTL_AUTH_TYPE: none # gateway terminates auth — see docs/upgrade-to-v2-jwt-removal.md
# ... rest of the certctl env block unchanged
```
Operators hit `https://<your-host>/`, get redirected through the OIDC provider, land back at oauth2-proxy with a session cookie, and oauth2-proxy proxies their request to certctl on the internal Docker network. certctl itself is HTTPS-only on `:8443` (TLS 1.3, see [`tls.md`](tls.md)) but operator browsers never see that hop directly. Bind certctl-server's `:8443` to the internal Docker network only — do NOT publish it to the host. The audit trail will record the actor as the gateway-forwarded identity if you also configure a small bearer-token-mapping shim at the gateway (most production deployments do this with a per-user api-key issued by the gateway after OIDC validation).
### Traefik ForwardAuth pattern (Kubernetes)
Same shape, kubernetes-flavored:
```yaml
apiVersion: traefik.io/v1alpha1
kind: Middleware
metadata:
name: oidc-forward-auth
spec:
forwardAuth:
address: http://oauth2-proxy.auth.svc.cluster.local:4180
trustForwardHeader: true
authResponseHeaders:
- X-Auth-Request-User
- X-Auth-Request-Email
- Authorization
---
apiVersion: traefik.io/v1alpha1
kind: IngressRoute
metadata:
name: certctl
spec:
routes:
- match: Host(`certctl.example.com`)
kind: Rule
middlewares:
- name: oidc-forward-auth
services:
- name: certctl-server
port: 8443
```
The certctl Helm release runs with `server.auth.type=none`. The Traefik IngressRoute attaches `oidc-forward-auth` as a middleware so every request is OIDC-validated by oauth2-proxy before reaching certctl.
### Envoy `ext_authz` pattern
For service-mesh deployments (Istio, Consul, plain Envoy), the `ext_authz` filter calls out to an external authorization service per-request. Same outcome: certctl runs `CERTCTL_AUTH_TYPE=none` and Envoy + your authz service handle JWT/OIDC/mTLS at the mesh edge. See the [Envoy ext_authz docs](https://www.envoyproxy.io/docs/envoy/latest/configuration/http/http_filters/ext_authz_filter) for the configuration surface.
## Rollback
Pre-G-1 binaries silently accepted `CERTCTL_AUTH_TYPE=jwt` and routed through the api-key middleware. Downgrading the binary is the only mechanical rollback path, and it puts you back into the silent-downgrade state — which is exactly what the G-1 audit finding is about. We don't recommend it. If something is forcing your hand, capture the operational issue you're hitting and open a GitHub issue against the certctl repo with the SHAs involved; the Authenticating-gateway pattern was specifically designed to cover the use cases that historically led operators to set `CERTCTL_AUTH_TYPE=jwt`.
There is no on-disk state that changes with this upgrade — no migrations to roll back, no encrypted config to re-encode, no certificates to re-issue. The change is entirely in the config-validation surface and the helm-chart template guard.
## Cross-references
- [`architecture.md`](architecture.md) — "Authenticating-gateway pattern (JWT, OIDC, mTLS)" section.
- [`tls.md`](tls.md) — TLS provisioning patterns. The gateway proxying to certctl-server still needs to trust certctl's TLS cert; same patterns apply.
- [`../deploy/helm/certctl/README.md`](../deploy/helm/certctl/README.md) — Helm-chart-flavored guidance.
- `internal/config/config.go::ValidAuthTypes` — the single source of truth for what's accepted post-G-1.
- `internal/repository/postgres/db.go::wrapPingError` — unrelated; pattern for runtime diagnostic of operator misconfiguration.
- `coverage-gap-audit-2026-04-24-v5/unified-audit.md` — the audit finding (`cat-g-jwt_silent_auth_downgrade`).