yau-plant-assistant/authelia/access-rules.md
Claude 16c4bba3bd Mark cube.yokogawa.tech as the hostname nothing depends on
Kept, but labelled. ai-api reaches Cube as cube:4000 over the proxy network and
never by name, and the operator UI never touches Cube - the hostname exists so
an engineer can open the playground to hand-verify a measure, which a tunnel
does equally well. So it is the first one to drop if this host is being tidied
or the name is wanted elsewhere.

The note is in three places because whoever tidies this host will be reading
one of them and not this repo: above the block in ~/Caddyfile, inline on the
Authelia rule, and here.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
2026-08-27 15:44:47 +10:00

6.5 KiB

Authelia access rules — the additions, as text

This file is documentation, not configuration. Never commit the real ~/authelia/configuration.yml, and never generate a replacement for it. It contains the AD bind account, session secrets and the Duo integration for every service on the host. The four hostnames below are the only part of it this project touches.

What has to change

Four hostnames join the existing HTTPS_UserAccess two_factor rule in ~/authelia/configuration.yml, under access_control.rules:

Hostname Phase Serves
lf.yokogawa.tech 2 Langfuse — traces, prompts, eval runs
cube.yokogawa.tech 5 Cube semantic layer, playground and REST API — not essential, see below
api.yokogawa.tech 6 ai-api FastAPI
ai.yokogawa.tech 7 ai-web operator UI

Phase 9 adds no hostname. It adds one path-scoped rule on an existing one — see "Phase 9: the document publisher rule" below.

The shape of the addition — the domain list on the existing trailing rule gains these entries, the policy and subject stay exactly as they already are:

access_control:
  rules:
    # ... existing rules unchanged ...
    - domain:
        # ... existing domains unchanged ...
        - lf.yokogawa.tech        # added <date>, AI PoC Phase 2
        - cube.yokogawa.tech      # added <date>, AI PoC Phase 5
        - api.yokogawa.tech       # added <date>, AI PoC Phase 6
        - ai.yokogawa.tech        # added <date>, AI PoC Phase 7
      policy: two_factor
      subject:
        - group:HTTPS_UserAccess

Add each hostname at the phase that needs it. Every domain added here must also have a Caddyfile block with import authelia (caddy/ai-routes.caddy), and every Caddyfile block must have a rule here. One without the other is a hole.

cube.yokogawa.tech is the one to drop first if the host is being tidied or the hostname is wanted for something else. Nothing depends on it — ai-api reaches Cube as cube:4000 over the proxy network and never by name, and the operator UI never touches Cube. It exists so an engineer can open the playground to hand-verify a measure, which an SSH tunnel does equally well. Removing it means deleting the Caddy block and this domain; batch that with an Authelia restart that is happening anyway rather than spending an all-user logout on it. The same note is on the host, in ~/Caddyfile above the block and inline on this rule.

Applied on lin001: lf on 2026-08-20; cube, api and ai on 2026-08-27, in one Authelia restart. Backup ~/authelia/configuration.yml.bak-ai-20260827. All four now return 302 to the auth portal. Between the Caddy blocks going in and this rule landing, the three new hostnames returned 403 — Caddy serving a hostname Authelia has no rule for means default_policy: deny, which is the safe direction but is not obvious from the status code alone. verify.sh names that case explicitly.

Phase 9: the document publisher rule

Operator document upload splits the API in two. Anyone in HTTPS_UserAccess may ask a question and upload a document for review. Approving a document — which is what makes it citable, and what decides whether a superseded revision stops being citable — needs a second group, AI_DocPublishers.

access_control:
  rules:
    # ... existing rules unchanged ...

    # MUST come BEFORE the general api.yokogawa.tech rule. Authelia applies the
    # FIRST matching rule and stops. Below it, this rule is dead and every
    # authenticated user can approve a procedure revision.
    - domain: api.yokogawa.tech
      resources:
        - '^/docs/.*'
      policy: two_factor
      subject:
        - group:AI_DocPublishers      # added <date>, AI PoC Phase 9

    # ... the existing trailing rule, unchanged, still carries
    #     api.yokogawa.tech for everyone in HTTPS_UserAccess ...

Three things about this rule specifically:

  • AI_DocPublishers must be created in AD with DIRECT membership. The same trap as HTTPS_UserAccess: a user inside a nested group is silently denied, with no useful log line. svc-authelia is read-only and cannot fix it.

  • It is not the only check. ai-api re-reads Remote-Groups and returns 403 on approve, reject and supersede. This rule protects the whole /docs path; the API protects the three operations that matter, and survives this rule being reordered or dropped in a future edit of a file nobody diffs.

  • Verify it by calling the API directly, as a user who is authenticated but not a publisher. The UI hides the buttons from that user, which proves nothing at all:

    curl -si https://api.yokogawa.tech/docs/uploads/<id>/approve        -X POST -H 'Content-Type: application/json' -d '{}'      # expect 403
    

How to apply it

# 1. Back up first. There are plenty of .bak-* precedents on the host.
sudo cp ~/authelia/configuration.yml ~/authelia/configuration.yml.bak-ai-$(date +%Y%m%d)

# 2. Edit with sudo - the file is root-owned. ~/apply_rule.py rewrites the
#    trailing rule if you prefer it to hand-editing.
sudo nano ~/authelia/configuration.yml

# 3. ANNOUNCE FIRST - this logs out every active user on every service.
docker compose -f ~/authelia-compose.yml restart authelia

# 4. Verify. "Up" is not proof.
curl -sI https://ai.yokogawa.tech        # expect 302 -> auth portal
docker logs --tail 50 authelia

Things that bite

  • Restarting Authelia logs out every active user on the host, including whoever is mid-demo on Grafana. Announce it, and batch the domain additions so you restart once per phase rather than once per hostname.
  • AD group membership must be DIRECT. Authelia resolves direct membership only; a user inside a nested group silently gets denied with no useful log line. Before Phase 7, confirm the demo operator account is a direct member of HTTPS_UserAccess and is Duo-enrolled. svc-authelia is read-only and cannot fix membership for you.
  • Rule order is a security control, not a style choice. First match wins. A path-scoped rule placed after the domain rule it narrows is inert, and nothing warns you — the service keeps working, for everybody.
  • A missing rule fails open at the wrong layer. Caddy will happily serve a hostname that has import authelia before the rule exists — Authelia then applies its default policy. Add the rule in the same change as the Caddyfile block and verify the 302 before telling anyone the URL.
  • Restarting Authelia is also the supported way to refresh someone's group membership after an AD change.