Harden admin login: RBAC-safe controls, 2FA, bot-scoring, rate limits (#9)

Adds a layered set of protections around the admin login and the app edge.

Trust proxy (server/src/utils/trustProxy.js)
- Configurable via TRUST_PROXY; pin to the newt agent ("ptero") LAN IP so
  X-Forwarded-For is trusted ONLY from that peer. A blanket "true" is
  rejected (coerced to 1) to prevent XFF spoofing that would dodge every
  IP-based control. DEBUG_TRUST_PROXY logs peer/XFF/req.ip to re-verify the
  proxy IP without a redeploy. Documents the Omada static-reservation
  assumption.

Login throttling (server/src/middleware/loginProtection.js, rateLimit.js)
- express-slow-down progressive delay + the existing hard rate cap + a
  separate per-IP exponential backoff that persists across the rate window.
  All failures return one generic message (no user/pass disclosure).

Honeypot (login form + auth.controller)
- Hidden, plausibly-named field ("company"); a filled value fails
  generically and is scored as an unambiguous bot.

Optional per-user TOTP 2FA (speakeasy/qrcode)
- totp_secret/totp_enabled columns (+ idempotent migration). Self-service
  Account page: enroll via QR, confirm a code to enable, code-gated disable.
- Login is two-step for enrolled users: after the password, a short-lived
  signed challenge (stage:'totp', not a session) is required before the
  real session is issued.

Bot / scanner scoring + IP ban (server/src/middleware/botScore.js)
- Weighted CMS-scanner paths (this app uses none). Junk paths 404 FIRST,
  unconditionally — independent of score/ban state, so a scanner rotating
  through fresh Cloudflare IPs gets no free pass. /wp-admin/install.php is
  the top-weighted near-1-hit ban (worst offender in prod logs). Per-IP
  score with quiet-period decay temp-bans an IP from ALL routes once past a
  (deliberately low) threshold, to protect /admin from credential stuffing.
  Failed logins and honeypot hits feed the same score.
- Periodic sweep evicts stale, unbanned, quiet entries so the in-memory
  store can't grow unbounded; the interval is unref'd and cleared on
  graceful shutdown.

Tests: node --test suite (40) covering trust-proxy parsing + live req.ip
(incl. pinned-IP), rate limiter + exponential backoff, honeypot rejection,
TOTP verify (enabled/disabled) + challenge-isn't-a-session, bot-score
threshold/decay/ban + junk-404-independence + install.php + store sweep.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

server/src/router/v1/auth/auth.controller.js

@@ -1,35 +1,105 @@
 const users = require('../../../model/users/users.model')
 const activity = require('../../../model/activity/activity.model')
-const { signToken, setAuthCookie, clearAuthCookie } = require('../../../utils/auth')
+const {
+  signToken,
+  setAuthCookie,
+  clearAuthCookie,
+  signTotpChallenge,
+  verifyTotpChallenge,
+} = require('../../../utils/auth')
+const totp = require('../../../utils/totp')
+const botScore = require('../../../middleware/botScore')
+const loginProtection = require('../../../middleware/loginProtection')
 
 const log = require('../../../utils/logger')('auth')
 
+// Honeypot input name — must match the hidden field rendered on the login form.
+// Chosen to look like a real field so naive bots fill it; real users never see it.
+const HONEYPOT_FIELD = 'company'
+
+// One generic failure response for every "you don't get in" case (wrong user,
+// wrong password, tripped honeypot). Never reveals which was wrong.
+const GENERIC_FAIL = { message: 'Incorrect username or password.' }
+
+// True when this user must complete a second factor before getting a session.
+function needsTotp(user) {
+  return Boolean(user && user.totp_enabled)
+}
+
+// Issue the real session: sign the JWT, set the cookie, clear the IP's failure
+// backoff, and record the login.
+async function issueSession(req, res, user) {
+  loginProtection.recordSuccess(req.ip)
+  await users.recordLogin(user.id)
+  const token = signToken(user)
+  setAuthCookie(req, res, token)
+  await activity.log({ req, userId: user.id, action: 'auth.login' })
+  log.info('login success', { username: user.username, id: user.id, ip: req.ip })
+  return res.json({ user: { id: user.id, username: user.username, role: user.role } })
+}
+
 async function login(req, res) {
   const { username, password } = req.body
+
+  // Honeypot: a populated hidden field means a bot. Fail generically, but score
+  // it hard — this is an unambiguous signal, unlike a mistyped password.
+  if (req.body[HONEYPOT_FIELD]) {
+    botScore.recordHoneypot(req.ip)
+    loginProtection.recordFailure(req.ip)
+    log.warn('honeypot login hit', { ip: req.ip, username })
+    return res.status(401).json(GENERIC_FAIL)
+  }
+
   try {
     const user = await users.getRawByUsername(username)
     const ok = user && (await users.validatePassword(user, password))
     if (!ok) {
+      botScore.recordLoginFailure(req.ip)
+      loginProtection.recordFailure(req.ip)
       log.warn('login failed', { username, ip: req.ip })
-      return res.status(401).json({ message: 'Incorrect username or password.' })
+      return res.status(401).json(GENERIC_FAIL)
     }
 
-    await users.recordLogin(user.id)
-    const token = signToken(user)
-    setAuthCookie(req, res, token)
-    await activity.log({ req, userId: user.id, action: 'auth.login' })
-    log.info('login success', { username: user.username, id: user.id, ip: req.ip })
+    // Password is correct. If this user has TOTP on, do NOT issue a session yet —
+    // hand back a short-lived, signed "password verified" challenge and require
+    // the code. If TOTP is off, log them straight in.
+    if (needsTotp(user)) {
+      const challenge = signTotpChallenge(user)
+      log.info('password ok, awaiting TOTP', { username: user.username, id: user.id, ip: req.ip })
+      return res.json({ totpRequired: true, challenge })
+    }
 
-    return res.json({
-      user: { id: user.id, username: user.username, role: user.role },
-    })
+    return issueSession(req, res, user)
   } catch (err) {
     log.error('login error', err)
     return res.status(500).json({ message: 'Internal Server Error' })
   }
 }
 
-async function logout(req, res) {
+// Second step for TOTP users: verify the challenge token + code, then issue the
+// session. A wrong code counts as a failed attempt (backoff + bot score).
+async function loginTotp(req, res) {
+  const { challenge, code } = req.body
+  const decoded = verifyTotpChallenge(challenge)
+  if (!decoded) {
+    return res.status(401).json({ message: 'Your verification session expired. Please sign in again.' })
+  }
+  try {
+    const user = await users.getRawById(decoded.id)
+    if (!user || !user.totp_enabled || !totp.verifyCode(user.totp_secret, code)) {
+      botScore.recordLoginFailure(req.ip)
+      loginProtection.recordFailure(req.ip)
+      log.warn('TOTP verify failed', { id: decoded.id, ip: req.ip })
+      return res.status(401).json({ message: 'Invalid verification code.' })
+    }
+    return issueSession(req, res, user)
+  } catch (err) {
+    log.error('loginTotp error', err)
+    return res.status(500).json({ message: 'Internal Server Error' })
+  }
+}
+
+function logout(req, res) {
   clearAuthCookie(req, res)
   return res.json({ message: 'Logged out.' })
 }
@@ -44,4 +114,4 @@ async function me(req, res) {
   }
 }
 
-module.exports = { login, logout, me }
+module.exports = { login, loginTotp, logout, me, needsTotp, HONEYPOT_FIELD }