Merge pull request 'Admin sits behind a 6-digit PIN' (#1) from claude/admin-pin into main

README.md

@@ -99,10 +99,19 @@ with this machine's shell settings — the same keys as the checked-in
 | Key | Meaning |
 | --- | --- |
 | `port` | Port ProdDash serves on (default `24500`). The macOS launcher writes this one, so the port it is set to holds however ProdDash is started. |
-| `adminPasscode` | If set, the admin page asks for this shared passcode. Leave `""` for none — it's a plain-HTTP LAN tool. |
+| `adminPin` | The admin PIN, as a scrypt hash. **Set it in the admin page's Admin PIN section**, not by hand — 6 digits, and only the hash is stored. Absent means admin is open to anyone on the network. |
+| `adminPasscode` | An older free-text passcode. Still honoured, so an existing install keeps working; new installs should use `adminPin`. |
 | `forge` | Where updates and module installs are fetched from. Absent or `"github"` uses GitHub; a Gitea or Forgejo base URL such as `"http://10.3.8.90:3000"` uses a server of your own. Set it per machine in the data directory, alongside `repo`. |
 | `theme` | The dashboard palette: `booth` (default), `harbor`, `graphite`, `ember` or `daylight`. The admin page's **Theme** section writes this one — see [Themes](#themes). |
 
+**Locked out?** Delete `adminPin` from the data directory's `proddash.json`
+and restart, or start the server with `PRODDASH_PASSCODE` set — that passcode
+overrides the PIN and always gets you in.
+
+Only `/admin` and the admin API are behind the PIN. Dashboards stay open, so a
+wall display needs no PIN, and it is unrelated to a module's own PIN (Slack's
+4–8 digit send PIN, say), which guards that module's actions only.
+
 **Updating from your own git server.** ProdDash fetches one `tar.gz` of the
 branch — nothing else — so any Gitea or Forgejo works. Point `forge` at its
 base URL and `repo` at the owner/repo there:

public/admin/admin.css

@@ -512,3 +512,49 @@ a.btn { text-decoration: none; }
   color: var(--accent);
 }
 #theme-status { margin-top: 4px; }
+
+/* ── the admin PIN ── */
+
+/* Digits, evenly spaced, so six of them read as a PIN rather than a word. */
+.pin-input {
+  font-variant-numeric: tabular-nums;
+  letter-spacing: 0.35em;
+  text-align: center;
+  max-width: 9em;
+}
+.pin-form {
+  display: flex;
+  flex-wrap: wrap;
+  align-items: flex-end;
+  gap: 12px;
+}
+.pin-field {
+  display: flex;
+  flex-direction: column;
+  gap: 4px;
+  font-size: 12px;
+  color: var(--muted);
+}
+.pin-field[hidden] { display: none; }
+.pin-field input {
+  padding: 8px 10px;
+  font-size: 14px;
+  color: var(--text);
+  background: var(--bg);
+  border: 1px solid var(--border);
+  border-radius: 7px;
+}
+.pin-field input:focus { outline: none; border-color: var(--accent); }
+.pin-actions {
+  display: flex;
+  gap: 8px;
+  margin-left: auto;
+}
+.pin-note { margin-top: 12px; }
+.pin-note code {
+  font-size: 0.92em;
+  padding: 1px 5px;
+  border-radius: 4px;
+  background: var(--bg);
+  border: 1px solid var(--border);
+}

public/admin/admin.js

@@ -2,8 +2,10 @@
 
    Everything here is server-wide: module enable/disable and admin config
    (written to config/modules.json, module re-inited on save), plus named
-   layout management. Guarded by the shared passcode when one is set. */
+   layout management. Behind the admin PIN when one is set — a shell setting of
+   its own, nothing to do with a module's PIN (Slack's send PIN, say). */
 
+const securitySection = document.getElementById('security-section');
 const loginCard = document.getElementById('login-card');
 const loginStatus = document.getElementById('login-status');
 const passcodeInput = document.getElementById('passcode');
@@ -62,20 +64,30 @@ function showLogin() {
   layoutsSection.hidden = true;
   updateCard.hidden = true;
   themeSection.hidden = true;
+  securitySection.hidden = true;
+  passcodeInput.value = '';
   passcodeInput.focus();
 }
 
+let loggingIn = false;
+
 async function login() {
+  if (loggingIn) return;
+  loggingIn = true;
   loginStatus.textContent = '';
   loginStatus.className = 'admin-status';
   try {
-    await api('/api/admin/login', { method: 'POST', body: JSON.stringify({ passcode: passcodeInput.value }) });
+    await api('/api/admin/login', { method: 'POST', body: JSON.stringify({ pin: passcodeInput.value }) });
     passcodeInput.value = '';
     loginCard.hidden = true;
     await loadState();
   } catch (e) {
+    passcodeInput.value = '';
     loginStatus.textContent = e.message;
     loginStatus.className = 'admin-status error';
+    passcodeInput.focus();
+  } finally {
+    loggingIn = false;
   }
 }
 
@@ -83,6 +95,83 @@ document.getElementById('login-btn').addEventListener('click', login);
 passcodeInput.addEventListener('keydown', (e) => {
   if (e.key === 'Enter') login();
 });
+// Six digits is the whole PIN, so there is nothing left to press.
+passcodeInput.addEventListener('input', () => {
+  passcodeInput.value = passcodeInput.value.replace(/\D/g, '').slice(0, 6);
+  if (passcodeInput.value.length === 6) login();
+});
+
+/* ── the admin PIN ───────────────────────────────────────────────────── */
+
+const pinCurrentField = document.getElementById('pin-current-field');
+const pinCurrent = document.getElementById('pin-current');
+const pinNew = document.getElementById('pin-new');
+const pinRepeat = document.getElementById('pin-repeat');
+const pinSaveBtn = document.getElementById('pin-save');
+const pinClearBtn = document.getElementById('pin-clear');
+const pinStatus = document.getElementById('pin-status');
+const pinStateEl = document.getElementById('pin-state');
+
+for (const input of [pinCurrent, pinNew, pinRepeat]) {
+  input.addEventListener('input', () => {
+    input.value = input.value.replace(/\D/g, '').slice(0, 6);
+  });
+}
+
+/** Paint the section for "no PIN yet" or "one is set". */
+function renderPin(state) {
+  const set = Boolean(state.pinSet);
+  const fromEnv = Boolean(state.pinFromEnv);
+  securitySection.hidden = false;
+  pinCurrentField.hidden = !set;
+  pinClearBtn.hidden = !set;
+  document.getElementById('pin-new-label').textContent = set ? 'New PIN' : 'PIN';
+  pinSaveBtn.textContent = set ? 'Change PIN' : 'Set PIN';
+  pinStateEl.textContent = fromEnv
+    ? 'A passcode is set in this server’s environment (PRODDASH_PASSCODE) and takes precedence. Anything set here applies once that is removed.'
+    : set
+      ? 'Admin is locked. This page asks for the PIN, and so does every admin request.'
+      : 'Admin is open to anyone on the network. Set a 6-digit PIN to lock it.';
+  if (state.dataDir) document.getElementById('pin-file').textContent = state.dataDir + '/proddash.json';
+}
+
+function pinMessage(text, bad = false) {
+  pinStatus.textContent = text;
+  pinStatus.className = 'admin-status' + (bad ? ' error' : ' ok');
+}
+
+async function savePin(clearing = false) {
+  pinStatus.textContent = '';
+  pinStatus.className = 'admin-status';
+  const current = pinCurrent.value;
+  const next = clearing ? '' : pinNew.value;
+  if (!clearing) {
+    if (!/^\d{6}$/.test(next)) return pinMessage('The PIN must be exactly 6 digits.', true);
+    if (next !== pinRepeat.value) return pinMessage('The two PINs are not the same.', true);
+  }
+  if (!pinCurrentField.hidden && !/^\d{6}$/.test(current)) {
+    return pinMessage('Enter the current PIN to change it.', true);
+  }
+  pinSaveBtn.disabled = true;
+  pinClearBtn.disabled = true;
+  try {
+    const body = await api('/api/admin/pin', { method: 'POST', body: JSON.stringify({ pin: next, current }) });
+    for (const i of [pinCurrent, pinNew, pinRepeat]) i.value = '';
+    pinMessage(body.pinSet ? 'PIN saved. It is asked for from the next visit.' : 'PIN removed — admin is open again.');
+    await loadState();
+  } catch (e) {
+    pinMessage(e.message, true);
+  } finally {
+    pinSaveBtn.disabled = false;
+    pinClearBtn.disabled = false;
+  }
+}
+
+pinSaveBtn.addEventListener('click', () => savePin(false));
+pinClearBtn.addEventListener('click', () => {
+  if (confirm('Turn the admin PIN off? Anyone on the network could then change this server’s settings.')) savePin(true);
+});
+pinRepeat.addEventListener('keydown', (e) => { if (e.key === 'Enter') savePin(false); });
 
 /* ── module cards ───────────────────────────────────────────────────── */
 
@@ -856,6 +945,7 @@ async function loadState() {
   for (const mod of state.modules || []) {
     modulesList.appendChild(buildModuleCard(mod));
   }
+  renderPin(state);
   loadTheme();
   loadLayouts();
   loadCatalog(false);

public/admin/index.html

@@ -18,10 +18,11 @@
 
   <main id="admin-main">
     <section class="admin-card" id="login-card" hidden>
-      <h2>Admin passcode</h2>
+      <h2>Admin PIN</h2>
       <p class="admin-copy">This page changes the server-wide configuration for every dashboard in the building.</p>
       <div class="login-row">
-        <input type="password" id="passcode" placeholder="Passcode" autocomplete="current-password">
+        <input type="password" id="passcode" class="pin-input" inputmode="numeric" autocomplete="off"
+               maxlength="6" placeholder="••••••" aria-label="Admin PIN">
         <button class="btn primary" id="login-btn">Unlock</button>
       </div>
       <div class="admin-status" id="login-status"></div>
@@ -65,6 +66,39 @@
       <h1 class="admin-h1">Saved layouts</h1>
       <div id="layouts-list"></div>
     </section>
+
+    <section id="security-section" hidden>
+      <h1 class="admin-h1">Admin PIN</h1>
+      <p class="admin-copy" id="pin-state"></p>
+      <div class="admin-card">
+        <div class="pin-form">
+          <label class="pin-field" id="pin-current-field" hidden>
+            <span>Current PIN</span>
+            <input type="password" id="pin-current" class="pin-input" inputmode="numeric"
+                   autocomplete="off" maxlength="6" placeholder="••••••">
+          </label>
+          <label class="pin-field">
+            <span id="pin-new-label">New PIN</span>
+            <input type="password" id="pin-new" class="pin-input" inputmode="numeric"
+                   autocomplete="off" maxlength="6" placeholder="6 digits">
+          </label>
+          <label class="pin-field">
+            <span>Repeat</span>
+            <input type="password" id="pin-repeat" class="pin-input" inputmode="numeric"
+                   autocomplete="off" maxlength="6" placeholder="6 digits">
+          </label>
+          <div class="pin-actions">
+            <button class="btn primary" id="pin-save">Set PIN</button>
+            <button class="btn" id="pin-clear" hidden>Turn off</button>
+          </div>
+        </div>
+        <p class="admin-copy pin-note">Only this page and the admin API ask for it — dashboards stay
+          open, and it is nothing to do with a module's own PIN, such as Slack's send PIN. Forgotten?
+          Remove <code>adminPin</code> from <code id="pin-file">proddash.json</code> in the settings
+          folder and restart.</p>
+        <div class="admin-status" id="pin-status"></div>
+      </div>
+    </section>
   </main>
 
   <div id="toast" hidden></div>

server.js

@@ -12,7 +12,8 @@
  * Configure via config/proddash.json (defaults, in the repo), an optional
  * proddash.json in the data directory (this machine's overrides), or env vars:
  *   PORT               (default: value in proddash.json, else 24500)
- *   PRODDASH_PASSCODE  (overrides adminPasscode in proddash.json)
+ *   PRODDASH_PASSCODE  (a passcode that overrides the stored admin PIN —
+ *                       also the way back in if the PIN is ever forgotten)
  *   PRODDASH_FORGE     (overrides `forge`: "github", or a Gitea/Forgejo base
  *                       URL such as http://10.3.8.90:3000)
  *   PRODDASH_DATA_DIR  (where module config + layouts are kept; see below)
@@ -1170,12 +1171,109 @@ function restartServer(reason) {
 
 /* ── admin API ──────────────────────────────────────────────────────── */
 
+/* Admin is behind a 6-digit PIN, set in the admin page and kept in this
+   machine's proddash.json as a scrypt hash — never in the clear, because that
+   file gets copied between machines. A dashboard needs no PIN; only /admin
+   and the admin API do. Two ways back in if it is ever forgotten: set
+   PRODDASH_PASSCODE in the environment, or delete "adminPin" from
+   proddash.json in the data directory and restart. `adminPasscode` (the older
+   free-text setting) still works so an existing install keeps running. */
+const PIN_RE = /^\d{6}$/;
+const PIN_MAX_WRONG = 5;
+const PIN_LOCKOUT_MS = 30000;
 const ADMIN_PASSCODE = String(process.env.PRODDASH_PASSCODE || shellConfig.adminPasscode || '');
-/** Session token: regenerating it every boot is fine — admins just re-enter the passcode. */
+/** Session token: regenerating it every boot is fine — admins just re-enter the PIN. */
 const adminToken = crypto.randomBytes(24).toString('hex');
+/** The stored PIN, as "scrypt$<salt>$<hash>"; '' when admin is open. */
+let adminPinHash = String(shellConfig.adminPin || '');
+const pinAttempts = new Map(); // ip → { count, lockedUntil }
+
+function hashPin(pin, salt = crypto.randomBytes(16).toString('hex')) {
+  return `scrypt$${salt}$${crypto.scryptSync(String(pin), salt, 32).toString('hex')}`;
+}
+
+/** Constant-time check of a PIN against the stored hash. */
+function pinMatches(given, stored) {
+  const parts = String(stored || '').split('$');
+  if (parts.length !== 3 || parts[0] !== 'scrypt') return false;
+  const expected = Buffer.from(parts[2], 'hex');
+  const actual = crypto.scryptSync(String(given), parts[1], expected.length);
+  return expected.length === actual.length && crypto.timingSafeEqual(expected, actual);
+}
+
+/** Is a credential required at all? */
+function adminLocked() {
+  return Boolean(ADMIN_PASSCODE || adminPinHash);
+}
+
+/** True when `given` is the credential in force (the env passcode, or the PIN). */
+function credentialOk(given) {
+  const s = String(given ?? '');
+  if (!s) return false;
+  if (ADMIN_PASSCODE) {
+    const a = Buffer.from(s);
+    const b = Buffer.from(ADMIN_PASSCODE);
+    if (a.length === b.length && crypto.timingSafeEqual(a, b)) return true;
+  }
+  return adminPinHash ? pinMatches(s, adminPinHash) : false;
+}
+
+function clientIp(req) {
+  return String(req.socket?.remoteAddress || 'unknown');
+}
+
+/** Seconds of lockout left for this address, or 0. */
+function lockoutLeft(ip) {
+  const a = pinAttempts.get(ip);
+  if (!a || !a.lockedUntil) return 0;
+  const left = a.lockedUntil - Date.now();
+  if (left <= 0) {
+    pinAttempts.delete(ip);
+    return 0;
+  }
+  return Math.ceil(left / 1000);
+}
+
+function noteWrongPin(ip) {
+  const a = pinAttempts.get(ip) || { count: 0, lockedUntil: 0 };
+  a.count += 1;
+  if (a.count >= PIN_MAX_WRONG) {
+    a.count = 0;
+    a.lockedUntil = Date.now() + PIN_LOCKOUT_MS;
+    console.warn(`[proddash] ${PIN_MAX_WRONG} wrong admin PINs from ${ip} — locked out for ${PIN_LOCKOUT_MS / 1000} s`);
+  }
+  pinAttempts.set(ip, a);
+}
+
+/**
+ * Store a new PIN (6 digits), or '' to open admin up again. Keeps every other
+ * key in this machine's proddash.json. Throws an httpError the route reports.
+ */
+function setAdminPin(pin) {
+  const next = String(pin ?? '');
+  if (next && !PIN_RE.test(next)) throw httpError(400, 'The PIN must be exactly 6 digits.');
+  const file = path.join(DATA_DIR, 'proddash.json');
+  let existing = {};
+  if (fs.existsSync(file)) {
+    existing = readJson(file, null);
+    if (!existing || typeof existing !== 'object' || Array.isArray(existing)) {
+      throw httpError(500, `${file} is not a JSON object — fix it by hand before changing the PIN.`);
+    }
+  }
+  const hash = next ? hashPin(next) : '';
+  const out = { ...existing };
+  if (hash) out.adminPin = hash;
+  else delete out.adminPin;
+  writeJson(file, out);
+  adminPinHash = hash;
+  shellConfig.adminPin = hash;
+  pinAttempts.clear();
+  console.log(`[proddash] admin PIN ${hash ? 'set' : 'removed — admin is open again'}`);
+  return { pinSet: Boolean(hash) };
+}
 
 function isAuthed(req) {
-  if (!ADMIN_PASSCODE) return true;
+  if (!adminLocked()) return true;
   const cookies = String(req.headers.cookie || '');
   return cookies.split(';').some((c) => c.trim() === 'proddash_admin=' + adminToken);
 }
@@ -1183,7 +1281,7 @@ function isAuthed(req) {
 /** Guard a state-changing admin route. Returns true when the request was refused. */
 function refuseAdminWrite(req, res) {
   if (!isAuthed(req)) {
-    sendJson(res, 401, { error: 'Enter the admin passcode first.', authRequired: true });
+    sendJson(res, 401, { error: 'Enter the admin PIN first.', authRequired: true });
     return true;
   }
   // Requiring application/json forces a CORS preflight that a hostile page
@@ -1268,10 +1366,19 @@ async function handleAdminApi(req, res, urlPath) {
     } catch {
       return sendJson(res, 400, { error: 'Malformed request.' });
     }
-    if (!ADMIN_PASSCODE) return sendJson(res, 200, { ok: true, authRequired: false });
-    if (String(body.passcode || '') !== ADMIN_PASSCODE) {
-      return sendJson(res, 403, { error: 'Wrong passcode.' });
+    if (!adminLocked()) return sendJson(res, 200, { ok: true, authRequired: false });
+    const ip = clientIp(req);
+    const left = lockoutLeft(ip);
+    if (left) return sendJson(res, 429, { error: `Too many wrong PINs — try again in ${left} s.`, retryAfter: left });
+    // `passcode` is what the older admin page sent; `pin` is what this one does.
+    if (!credentialOk(body.pin ?? body.passcode)) {
+      noteWrongPin(ip);
+      const now = lockoutLeft(ip);
+      return sendJson(res, 403, now
+        ? { error: `Too many wrong PINs — try again in ${now} s.`, retryAfter: now }
+        : { error: 'Wrong PIN.' });
     }
+    pinAttempts.delete(ip);
     res.writeHead(200, {
       'Content-Type': 'application/json; charset=utf-8',
       'Set-Cookie': `proddash_admin=${adminToken}; Path=/; SameSite=Lax; HttpOnly`,
@@ -1280,12 +1387,50 @@ async function handleAdminApi(req, res, urlPath) {
     return res.end(JSON.stringify({ ok: true }));
   }
 
+  if (urlPath === '/api/admin/pin' && req.method === 'POST') {
+    if (refuseAdminWrite(req, res)) return;
+    let body = {};
+    try {
+      body = JSON.parse((await readBody(req)) || '{}');
+    } catch {
+      return sendJson(res, 400, { error: 'Malformed request.' });
+    }
+    // Changing a credential re-asserts it, so a browser left open on the
+    // admin page can't be used to take the machine over.
+    if (adminPinHash) {
+      const ip = clientIp(req);
+      const left = lockoutLeft(ip);
+      if (left) return sendJson(res, 429, { error: `Too many wrong PINs — try again in ${left} s.`, retryAfter: left });
+      if (!pinMatches(String(body.current ?? ''), adminPinHash)) {
+        noteWrongPin(ip);
+        return sendJson(res, 403, { error: 'That is not the current PIN.' });
+      }
+      pinAttempts.delete(ip);
+    }
+    try {
+      const result = setAdminPin(body.pin);
+      // Whoever just set it has proved they are allowed, so hand them the
+      // session rather than bouncing them to the unlock card they just built.
+      res.writeHead(200, {
+        'Content-Type': 'application/json; charset=utf-8',
+        'Set-Cookie': `proddash_admin=${adminToken}; Path=/; SameSite=Lax; HttpOnly`,
+        'Cache-Control': 'no-store',
+      });
+      return res.end(JSON.stringify(result));
+    } catch (err) {
+      return sendJson(res, err.status || 500, { error: err.message || 'Could not save the PIN.' });
+    }
+  }
+
   if (urlPath === '/api/admin/state' && req.method === 'GET') {
     if (!isAuthed(req)) {
       return sendJson(res, 401, { authRequired: true, authed: false });
     }
     return sendJson(res, 200, {
-      authRequired: Boolean(ADMIN_PASSCODE),
+      authRequired: adminLocked(),
+      // The env passcode can't be changed from here; the page says so.
+      pinSet: Boolean(adminPinHash),
+      pinFromEnv: Boolean(ADMIN_PASSCODE),
       authed: true,
       version: SHELL_VERSION,
       dataDir: DATA_DIR,
@@ -1466,7 +1611,7 @@ async function handleLayoutsApi(req, res, urlPath) {
   }
 
   if (!m[2] && req.method === 'DELETE') {
-    if (!isAuthed(req)) return sendJson(res, 401, { error: 'Enter the admin passcode first.', authRequired: true });
+    if (!isAuthed(req)) return sendJson(res, 401, { error: 'Enter the admin PIN first.', authRequired: true });
     try {
       fs.unlinkSync(layoutPath(name));
     } catch {