# Authentication standards implemented

> Last reviewed: 2026-05-10

This document is an honest informational reference for operators, external testers, and acquirers who want to know which RFCs and standards certctl's authentication surface (API keys + RBAC + OIDC + sessions + back-channel logout + break-glass admin) implements, and which CWE weakness classes the implementation closes. Every row points at a real file or migration in this repository.

This document is intentionally NOT a compliance-mapping doc. The operator retired the framework-mapping subtree (`docs/compliance/{index,soc2,pci-dss,nist-sp-800-57}.md`) on 2026-05-05; framework-name-drops (SOC 2 / PCI-DSS / HIPAA / NIST SSDF / FedRAMP) are also swept from prose mentions across `README.md` and `docs/` per that decision. RFC and CWE references stay because they are precise technical pointers; framework labels were marketing-flavored and prone to overclaim. If you are an auditor mapping certctl's controls to a framework, treat the rows below as evidence and do the framework mapping yourself against the framework you are auditing against.

For the wider security posture, see [`security.md`](../operator/security.md). For the threat model behind these controls, see [`auth-threat-model.md`](../operator/auth-threat-model.md). For the per-IdP setup guides, see [`oidc-runbooks/index.md`](../operator/oidc-runbooks/index.md).

## Table 1: RFCs and standards implemented end-to-end

Each row carries at least one negative test (a test that asserts the fail-closed branch fires when a malformed input violates the spec).

| Standard | What we implement | Source | Negative-test anchor |
|---|---|---|---|
| RFC 6749 (OAuth 2.0) | Authorization-code grant via OIDC; confidential-client credentials only | `internal/auth/oidc/service.go` (HandleAuthRequest, HandleCallback) | `internal/auth/oidc/service_test.go` (21+ negatives covering wrong aud / wrong iss / expired / etc.) |
| RFC 7636 (PKCE) | S256 challenge mandatory; `plain` rejected at the service-layer sentinel; verifier persisted in pre-login row, single-use | `internal/auth/oidc/service.go` (oauth2.S256ChallengeOption hard-coded), `internal/auth/oidc/prelogin.go` | `TestService_PKCEPlainRejectedSentinel`, `TestService_StateReplayDeniedByConsumeOnce` |
| RFC 7519 (JWT) | ID-token validation via go-oidc; service-layer alg allow-list (RS256/RS512/ES256/ES384/EdDSA); HS-family + `none` rejected | `internal/auth/oidc/service.go` (disallowedAlgs map, isDisallowedAlg) | `TestService_HandleCallback_RejectsHSAlgsConfusion`, `TestService_IdPDowngradeDefense_RejectsHSAdvertised` |
| RFC 7517 (JWK) | JWKS fetch + cache + rotation handled transparently by coreos/go-oidc; operator-triggered RefreshKeys + auto-refresh on TTL expiry | `internal/auth/oidc/service.go` (RefreshKeys; cfg.JWKSCacheTTLSeconds default 3600) | `TestService_RefreshKeys_CatchesPostLoadDowngrade`, `TestKeycloakIntegration_JWKSRotation_RefreshKeysPicksUpNewKey` (Keycloak integration) |
| OIDC Core 1.0 §3.1.3.7 | `iss` exact match, `aud` membership, `azp` for multi-aud, `at_hash` REQUIRED-when-access_token-present (certctl tightens the spec MAY → MUST), `nonce` constant-time-compare | `internal/auth/oidc/service.go` (HandleCallback steps 5-9) | `TestService_HandleCallback_RejectsWrongAudience`, `TestService_HandleCallback_AZPRequiredOnMultiAud`, `TestService_HandleCallback_ATHashRequiredWhenAccessTokenPresent`, `TestService_HandleCallback_RejectsNonceMismatch` |
| OIDC Core 1.0 §5.3.2 (UserInfo endpoint) | Optional fallback when ID-token groups claim is empty; bounded by configured FetchUserinfo bool | `internal/auth/oidc/service.go` (fetchUserinfoGroups) | 4-case userinfo-fallback matrix in `service_test.go` (happy + endpoint-missing + endpoint-failing + userinfo-also-empty) |
| OpenID Connect Back-Channel Logout 1.0 | `events` claim + `sid`/`sub` revocation; `nonce` MUST be absent; `jti`-based replay defense | `internal/api/handler/auth_session_oidc.go` (BackChannelLogout, DefaultBCLVerifier) | 6 negatives in `auth_session_oidc_test.go`: BCL missing events, BCL nonce-present, BCL unknown-key-sig, etc. |
| RFC 6265 (HTTP State Management) | Session cookie attributes: `Secure` + `HttpOnly` + `SameSite=Lax` (default; configurable to Strict via `CERTCTL_SESSION_SAMESITE`); `Path=/`; host-only | `internal/auth/session/service.go` (cookie minting), `internal/api/handler/auth_session_oidc.go` (Set-Cookie wiring) | 7-case middleware-chain test matrix in `internal/auth/session/middleware_test.go` |
| RFC 9700 (OAuth 2.0 Security Best Current Practice) | PKCE mandatory; no implicit flow; strict redirect_uri (registered + exact-match per OIDCProvider.RedirectURI); state non-guessable (32-byte random); single-use | `internal/auth/oidc/service.go`; `OIDCProvider.Validate()` enforces redirect_uri shape | `TestOIDCProvider_Validate_RejectsHTTPRedirectInProd`, state-replay test |
| RFC 8414 (OAuth 2.0 Authorization Server Metadata) | Discovery doc fetched via go-oidc at provider creation + RefreshKeys; `id_token_signing_alg_values_supported` consulted for IdP-downgrade-attack defense | `internal/auth/oidc/service.go` (getOrLoad, guardAdvertisedAlgs) | `TestService_IdPDowngradeDefense_RejectsHSAdvertised` and `RejectsNoneAdvertised` |
| RFC 7633 (X.509 TLS Feature Extension; Must-Staple) | Per-profile certctl issuance flag; out-of-scope for the auth surface but cited here because RFC 7633 OID `id-pe-tlsfeature` is in the same crypto-stack umbrella | `internal/connector/issuer/local/local.go` | SCEP master-bundle must-staple tests; not auth-surface territory |
| RFC 8555 §7 (ACME directory metadata) | certctl-side ACME server tier; out-of-scope for the auth surface but cited because it shares the alg-pinning + nonce-handling discipline the auth surface carries forward | `internal/api/handler/acme/*` | per-route handler tests in `internal/api/handler/acme/` |
| RFC 7515 (JWS) | JWS verification delegated to go-oidc/v3 + go-jose/v4; alg pin enforced at `gooidc.NewIDTokenVerifier` config + service-layer re-check | `internal/auth/oidc/service.go` (oauthConfig + verifier wiring) | `TestService_HandleCallback_RejectsExpired` and `TestService_HandleCallback_RejectsIATInFuture` |

## Table 2: CWE / weakness classes the implementation closes

Each row points at the file(s) that implement the defense and the test file(s) that pin the invariant.

| CWE | Description | Where defended | Where pinned |
|---|---|---|---|
| CWE-287 (Improper Authentication) | Session-cookie HMAC verification (length-prefixed input defeats concat-collision) + alg-pinned ID-token verify | `internal/auth/session/service.go` (computeHMAC, parseCookie, Validate); `internal/auth/oidc/service.go` (HandleCallback) | `TestComputeHMAC_LengthPrefixDefeatsConcatCollision`; `TestService_Validate_ConcatenationCollisionDefeatedByLengthPrefix`; full 21+ OIDC negatives matrix |
| CWE-352 (Cross-Site Request Forgery) | Double-submit cookie + `SameSite=Lax`/`Strict` + hashed CSRF token on session row; constant-time compare in CSRFMiddleware | `internal/auth/session/middleware.go` (CSRFMiddleware) | 7-case middleware-chain matrix (`internal/auth/session/middleware_test.go`); `TestSessionMiddleware_CSRFRequiredOnStateChangingMethods` |
| CWE-384 (Session Fixation) | Session ID is opaque random `ses-<base64url>` (32 bytes entropy) generated server-side at login; cookie value rotates on every login (no inheritance from pre-login); CSRF token rotates alongside | `internal/auth/session/service.go` (Create, RotateCSRFToken) | `TestService_Create_AssignsFreshSessionID`; CSRF rotation pinned via `TestService_RotateCSRFToken_AfterLogin` |
| CWE-294 (Authentication Bypass by Capture-Replay) | Single-use state, single-use nonce (both stored in pre-login row, atomic `DELETE...RETURNING` on consume); single-use authorization code (Keycloak/IdP-side); `jti`-based BCL replay defense | `internal/auth/oidc/prelogin.go` (LookupAndConsume); `internal/api/handler/auth_session_oidc.go` (BCL handler) | `TestService_StateReplayDeniedByConsumeOnce`; `TestService_HandleCallback_RejectsForgedPreLoginCookie`; BCL replay negative in handler tests |
| CWE-916 / CWE-329 (Use of Password Hash With Insufficient Computational Effort / Use of a Key Past its Expiration Date) | Argon2id with OWASP 2024 params (m=64 MiB, t=3, p=4, 16-byte salt, 32-byte output) for break-glass passwords; per-credential random salt; PHC-format hash | `internal/auth/breakglass/service.go` (HashPassword, VerifyPassword); v3 ciphertext blob format with PBKDF2-SHA256 600,000 rounds for config-at-rest encryption | `TestPhase7_5_HashPasswordOWASP2024Params`; `TestPhase7_5_HashFormatPHC`; `internal/crypto/encryption_test.go` for v3 PBKDF2 floor |
| CWE-307 (Improper Restriction of Excessive Authentication Attempts) | Failure count + lockout window on break-glass credential; threshold default 5, reset window default 1h, lockout duration default 30s; atomic single-statement IncrementFailure defeats concurrent racing attempts | `internal/auth/breakglass/service.go` (Login, IncrementFailure); `internal/repository/postgres/breakglass.go` | `TestPhase7_5_LockoutAfterThresholdFailures`; `TestPhase7_5_FailureCountResetsAfterWindow` |
| CWE-345 (Insufficient Verification of Data Authenticity) | OIDC `at_hash` REQUIRED-when-access_token-present ties access token to ID token (certctl tightens OIDC core MAY → MUST); OIDC `iss` + `aud` + `azp` checks ensure token came from the configured IdP for the configured client | `internal/auth/oidc/service.go` (HandleCallback steps 5-9, atHashMatches) | `TestService_HandleCallback_ATHashRequiredWhenAccessTokenPresent`; `TestService_HandleCallback_RejectsATHashMismatch` |
| CWE-200 (Information Exposure) | Token-leak hygiene tests on every secret-bearing path: ID tokens, access tokens, refresh tokens, authorization codes, PKCE verifiers, state, nonce, signing keys, break-glass passwords NEVER appear in any log line at any level | `internal/auth/oidc/service.go`, `internal/auth/session/service.go`, `internal/auth/breakglass/service.go` (all log calls audited); `internal/service/audit_redact.go` (audit redactor) | `internal/auth/oidc/logging_test.go` (4 grep-asserts); `internal/auth/breakglass/service_test.go` (token-leak hygiene + json.Marshal probe); `internal/auth/bootstrap/service_test.go` (canonical pattern) |
| CWE-770 (Allocation of Resources Without Limits or Throttling) | Per-IP rate limit on `/auth/breakglass/login` via the global middleware.NewRateLimiter (default RPS / burst from `CERTCTL_RATE_LIMIT_*` env vars) wrapped around the entire mux; the breakglass login endpoint inherits this protection. Per-route override available via `middleware.NewRateLimiter` per-bucket configuration if the operator wants stricter caps | `cmd/server/main.go` (rateLimiter wiring at the root middleware stack); `internal/api/middleware/middleware.go` (NewRateLimiter) | `internal/api/middleware/ratelimit_test.go`; `internal/api/middleware/ratelimit_keyed_test.go` |
| CWE-330 (Use of Insufficiently Random Values) | `crypto/rand` for state, nonce, PKCE verifier (via `oauth2.GenerateVerifier`), session signing keys (32 random bytes), session IDs (`ses-<base64url-no-pad>` from 32 random bytes), pre-login IDs (`pl-<base64url-no-pad>` from 16 random bytes), CSRF tokens (32 random bytes), break-glass salts (16 random bytes via `crypto/rand`) | `internal/auth/oidc/service.go` (randomB64URL); `internal/auth/session/service.go` (newOpaqueID, newCSRFToken); `internal/auth/oidc/prelogin.go` (newID); `internal/auth/breakglass/service.go` (HashPassword salt) | `TestPreLoginAdapter_CreatePreLogin_RNGFailure` (entropy-source error path); RNG failure pinned for every callsite |
| CWE-311 (Missing Encryption of Sensitive Data) | OIDC `client_secret` AES-256-GCM encrypted at rest (v3 blob format: magic 0x03 + salt(16) + nonce(12) + ciphertext+tag); session signing keys same scheme; empty `CERTCTL_CONFIG_ENCRYPTION_KEY` returns `ErrEncryptionKeyRequired` (fail-closed) | `internal/crypto/encryption.go` (EncryptIfKeySet, DecryptIfKeySet); `internal/api/handler/auth_session_oidc.go` (encryptClientSecret); `internal/auth/session/service.go` (KeyMaterialEncrypted) | `internal/repository/postgres/oidc_encryption_invariant_test.go` (invariant test: ciphertext != plaintext, v2/v3 blob shape, round-trip + wrong-passphrase fails) |
| CWE-326 (Inadequate Encryption Strength) | TLS 1.3 only on the certctl control plane (post-v2.2 milestone); HSTS-equivalent posture via HTTPS-only listener; AES-256-GCM for at-rest config encryption; PBKDF2-SHA256 600,000 rounds for v3 blob key derivation (OWASP 2024 floor) | `cmd/server/main.go` (TLS 1.3 listener config); `internal/crypto/encryption.go` (v3 PBKDF2 iteration count) | `TestServerTLSConfig_RejectsTLS12`; `TestEncryption_V3IterationCount_PinnedAtOWASP2024Floor` |
| CWE-1004 (Sensitive Cookie Without HttpOnly) | Session cookie set with `HttpOnly=true`; CSRF cookie intentionally `HttpOnly=false` so the GUI can read it for the `X-CSRF-Token` header (the read is by-design per the double-submit-cookie pattern) | `internal/auth/session/service.go` (cookie attrs); `internal/api/handler/auth_session_oidc.go` (Set-Cookie wiring) | Cookie-attribute pinning in handler tests; documented in [auth-threat-model.md](../operator/auth-threat-model.md) "Session minting + cookies" subsection |
| CWE-614 (Sensitive Cookie in HTTPS Session Without 'Secure' Attribute) | Session + CSRF cookies set with `Secure=true`; rejected at cookie-write time on `http://` listeners (HTTPS-only control plane post-v2.2) | `internal/auth/session/service.go`; `cmd/server/main.go` HTTPS-only listener | TLS-listener tests in `cmd/server/`; cookie attrs pinned in handler tests |
| CWE-1275 (Sensitive Cookie with Improper SameSite Attribute) | Session cookie `SameSite=Lax` default (configurable to Strict via `CERTCTL_SESSION_SAMESITE`); CSRF defense via the double-submit pattern means `Lax` is sufficient even if the operator does not flip to Strict | `internal/auth/session/service.go` (cookie attrs); `internal/config/config.go` (SAMESITE env var) | Cookie-attribute pinning; SameSite enforcement is per-cookie | 

## API-key + RBAC standards covered separately

The above tables focus on the OIDC + sessions + back-channel logout + break-glass surface. The RBAC primitive carries its own implementation pointers; the [`auth-threat-model.md`](../operator/auth-threat-model.md) section "API-key + RBAC defenses" enumerates the full RBAC + bootstrap + auditor + approval-workflow surface. CWE-pointers that apply to the RBAC surface:

- CWE-285 (Improper Authorization) — defended by the RequirePermission middleware + Authorizer.CheckPermission service-layer call. Pinned by 90+ tests across `internal/auth/` and `internal/service/auth/`.
- CWE-862 (Missing Authorization) — pinned by `phase12_protocol_allowlist_test.go` (asserts protocol endpoints are explicitly allowlisted, NOT silently bypassing the gate).
- CWE-863 (Incorrect Authorization) — pinned by the auditor-split invariant in `internal/domain/auth/auditor_test.go` (auditor role holds exactly `audit.read` + `audit.export` ONLY).
- CWE-732 (Incorrect Permission Assignment for Critical Resource) — five admin-only fine-grained perms (`cert.bulk_revoke`, `crl.admin`, `scep.admin`, `est.admin`, `ca.hierarchy.manage`) seeded into `r-admin` only; pinned by migration 000030 + `r-admin`-only seed test.

## What this document is NOT

To preserve the operator's 2026-05-05 retired-compliance-docs decision:

- This is NOT a SOC 2 / PCI-DSS / HIPAA / NIST SP 800-53 / NIST SSDF / FedRAMP framework-mapping doc.
- This is NOT a marketing claim that certctl "satisfies CC6.1" or "complies with §164.312(a)(2)(iii)" or any similar framework label.
- This IS an evidence list. An auditor doing framework mapping for their own compliance purposes can use this list as the source-of-truth pointer, then map each row to the framework control they are auditing against under their own judgment.

If you are an external tester, an operator's auditor, or an acquirer doing technical diligence, this document gives you concrete file paths to read and concrete tests to run. If you want a framework-mapping document, build it yourself against the rows here using the framework-mapping methodology your audit firm prescribes; this project does not own that mapping.

## Cross-references

- [`auth-threat-model.md`](../operator/auth-threat-model.md) — threat model behind these defenses.
- [`security.md`](../operator/security.md) — overall security posture.
- [`oidc-runbooks/index.md`](../operator/oidc-runbooks/index.md) — per-IdP operator setup guides.
- [`auth-benchmarks.md`](../operator/auth-benchmarks.md) — performance baselines for the validation paths cited above.
- `internal/auth/oidc/` — OIDC service + groupclaim resolver + pre-login adapter + bootstrap hook.
- `internal/auth/session/` — Session service + middleware + CSRF + signing-key rotation.
- `internal/auth/breakglass/` — break-glass admin (Argon2id + lockout + constant-time + surface-invisibility).
- `internal/crypto/encryption.go` — AES-256-GCM v3 blob format for at-rest encryption.
- `migrations/000029` through `000038` — schema for RBAC, OIDC providers, sessions, signing keys, users, group mappings, pre-login, break-glass.
- `scripts/ci-guards/multi-tenant-query-coverage.sh` — forward-compat multi-tenant query coverage guard.
