docs: TLS audit offload bench-verified (poam-hardening-5bc6d27) — all gates passed

docs/stig-deviations.md

@@ -27,7 +27,7 @@ Posture decisions (2026-06-18, lab phase; offload updated 2026-07-12):
 | 3 | **AIDE / file integrity** (`package_aide_installed`, `aide_build_database`, `aide_periodic_cron_checking`, `aide_scan_notification`, `aide_verify_*`) | The root is read-only and cryptographically verified; an on-disk AIDE db would also be non-deterministic and break the reproducible verity hash. | **dm-verity** verifies the whole root filesystem against a signed root hash on every read — continuous, hardware-backed integrity that supersedes AIDE's periodic scan. |
 | 4 | **Firewall** (`service_firewalld_enabled`, `package_firewalld_installed`, `set_firewalld_default_zone`) | Currently `firewall --disabled`; auto-enabling firewalld/nftables risks the NVMe/TCP (`:4420`) and NetworkManager paths during bring-up. | Isolated boot LAN; egress controlled at the serving-stack / network firewall layer. **Future hardening** — re-enable with explicit allow rules once the secure path is verified. |
 | 5 | **FIPS** (`enable_fips_mode`, `grub2_enable_fips_mode`, `package_dracut-fips_installed`) | Decision: off for the lab phase (interacts with the still-unsigned UKI / Secure Boot story). | Revisit with signing. No weakened crypto is configured in the meantime. |
-| 6 | **Remote audit offload** (`auditd_audispd_configure_remote_server`, `..._encrypt_sent_records`, `..._network_failure_action`, `rsyslog_remote_loghost`) | Offload is done via **rsyslog over TLS** rather than the `audisp-remote` native protocol (simpler, container-friendly receiver), so the audisp-remote rules + `rsyslog_remote_loghost` (whose remediation would inject a bogus loghost) stay waived — the *intent* of all four is met by the rsyslog path. **The three `rsyslog_encrypt_offload_*` rules are NO LONGER waived** (re-selected 2026-07-12): the offload is now encrypted end-to-end and they are evaluated + expected to **pass** (rsyslog+rsyslog-gnutls installed before the scan; remediation writes the gtls/x509 globals). | **Wired both ends, TLS.** Sender (image, provisioner 2f, `audit_host`): audisp-syslog → LOCAL6 + rsyslog `omfwd` over **gtls :6514**, server verified `x509/name` against the baked fleet CA (`/etc/dot1x/radius-ca.pem`, `var.fleet_ca`), disk-assisted queue → host-generic `audit.fleet.lab`. Receiver: `serving/audit-collector/` (gtls listener :6514, server cert from the fleet step-ca via `issue-cert.sh`; legacy plaintext :514 kept only for pre-TLS images during migration — close it once the fleet is on TLS images). No client certs: hosts are fleet-generic (invariant #1 — a baked fleet-wide client key would be shared secret material), and client mTLS with the per-host **TPM identity was considered + deferred 2026-07-12** (redundant with 802.1X/MACsec on the secure path, which authenticates the same TPM credential at L2; rsyslog can't use a non-exportable TPM key without a delegated-cert or PKCS#11-tunnel contraption; hard-failing the forensic safety net on client-auth errors darkens exactly the hosts whose logs matter most — full rationale + revisit trigger in `serving/audit-collector/README.md`). Sender access constrained by the isolated boot LAN + serving-host firewall. No per-host state. |
+| 6 | **Remote audit offload** (`auditd_audispd_configure_remote_server`, `..._encrypt_sent_records`, `..._network_failure_action`, `rsyslog_remote_loghost`) | Offload is done via **rsyslog over TLS** rather than the `audisp-remote` native protocol (simpler, container-friendly receiver), so the audisp-remote rules + `rsyslog_remote_loghost` (whose remediation would inject a bogus loghost) stay waived — the *intent* of all four is met by the rsyslog path. **The three `rsyslog_encrypt_offload_*` rules are NO LONGER waived** (re-selected 2026-07-12): the offload is encrypted end-to-end and all three **pass** in the scan of record (build `poam-hardening-5bc6d27`; rsyslog+rsyslog-gnutls installed before the scan; remediation writes the gtls/x509 globals). Bench-verified same day incl. evil-twin rejection + lossless spool drain (TODO #8). | **Wired both ends, TLS.** Sender (image, provisioner 2f, `audit_host`): audisp-syslog → LOCAL6 + rsyslog `omfwd` over **gtls :6514**, server verified `x509/name` against the baked fleet CA (`/etc/dot1x/radius-ca.pem`, `var.fleet_ca`), disk-assisted queue → host-generic `audit.fleet.lab`. Receiver: `serving/audit-collector/` (gtls listener :6514, server cert from the fleet step-ca via `issue-cert.sh`; legacy plaintext :514 kept only for pre-TLS images during migration — close it once the fleet is on TLS images). No client certs: hosts are fleet-generic (invariant #1 — a baked fleet-wide client key would be shared secret material), and client mTLS with the per-host **TPM identity was considered + deferred 2026-07-12** (redundant with 802.1X/MACsec on the secure path, which authenticates the same TPM credential at L2; rsyslog can't use a non-exportable TPM key without a delegated-cert or PKCS#11-tunnel contraption; hard-failing the forensic safety net on client-auth errors darkens exactly the hosts whose logs matter most — full rationale + revisit trigger in `serving/audit-collector/README.md`). Sender access constrained by the isolated boot LAN + serving-host firewall. No per-host state. |
 | 7 | **Smart card login** (`require_smart_card_login`, `sssd_enable_smartcard`, `install_smartcard_packages`) | Diskless hosts have no smartcard reader; admin access is SSH key-based. Enforcing smartcard login would lock the host out. | Admin auth is an SSH **key-only** account; root is locked; password auth disabled. |
 | 8 | **NOPASSWD sudo** (`sudo_remove_nopasswd`) | The baked admin is a **passwordless, key-only** account, so `sudo` cannot prompt for a password — NOPASSWD is required for it to function at all. | Single fleet-generic admin, key-only, `wheel`; no interactive password exists to protect. Tracked for the eventual per-host/rotatable access model (SSH CA / config-agent). |
 | 9 | **GUI / autologin / GDM** (gnome screensaver, GDM banner, automatic-login rules) | No GNOME/GDM is installed; the kiosk is an **intentional** autologin single-app (weston + Chromium) session on kiosk builds. | Kiosk user is unprivileged and passwordless; the session runs a single locked-down browser (no shell, no nav). Applies to kiosk builds only; non-kiosk builds don't install the GUI stack. |