feature: the firewall lets the Router Manager in on the internal interface.

ADR.md

@@ -189,3 +189,29 @@ options at all. They are recognised by name as before: `psk`, and options with `
 
 Consequences: No secret reaches the web service's state file or any answer of the API. A client
 cannot tell whether a secret is set. A new secret option still needs a name that matches.
+
+## ADR-9: The Router Manager is a separate package with a small Python server
+
+Status: Accepted
+
+Context: The router needs a web application to manage it, which may run on the router or on
+another Linux system. The router's web service needs a token signed with `web.jwt_secret` for
+`/config` and `/users` and sends no CORS headers, so a browser cannot call it with the secret
+kept away from the page.
+
+Decision: `vpn-router-manager` is a Debian package of its own, built in the repository `linux-cloud-router-manager`. A React and
+MUI application in the style of manage-ui is built with Vite when the package is built and
+shipped as static files. A Python server, using the Ubuntu packages `python3-jwt` and `python3-requests`, serves them and
+passes every `/api/<path>` call to the router's `/<path>`, signing a short-lived token with the
+router's secret; it holds no logic of the router's own. It reads its settings from
+`/etc/vpn-router-manager/manager.json` at each request; on the router the settings not given
+come from `vpn-router.json`, and it listens on the internal address like the status web
+service, with the same discovery thread. `vpn-router-setup` opens the manager's port on the
+internal interface while the manager is installed, so the firewall stays in one place. The
+manager asks for no authentication yet.
+
+Consequences: The router needs no Node.js; the package needs only `python3` and packages of the Ubuntu archive. The secret never
+reaches the browser. The application checks the shape of every answer of the router. Anyone who
+reaches the manager's port manages the router, so on another system it listens on `127.0.0.1`
+unless told otherwise. The router's firewall depends on whether the manager is installed, and a
+changed manager port needs `vpn-router-setup` to run again.

README.md

@@ -502,6 +502,14 @@ request reads the token secret from `vpn-router.json`, and the features and the
 before that file exists the page shows no features. `vpn-router-setup` opens `web.port` on the
 internal interface in the firewall.
 
+## Router Manager
+
+The `vpn-router-manager` package, built in the repository `linux-cloud-router-manager`, is a web
+application that shows the state of the router and manages its users through the status web
+service. It can be installed on the router or on another Linux system. While it is installed on
+the router, `vpn-router-setup` opens its port (`port` in `/etc/vpn-router-manager/manager.json`,
+8090 by default) on the internal interface; restart `vpn-router-setup` after changing it.
+
 ## Removal
 
 `apt-get remove` stops `vpn-router-docker`, which removes the Docker rules. It terminates the

debian-package/debian/changelog

@@ -1,3 +1,13 @@
+vpn-router (0.5.4-1) unstable; urgency=medium
+
+  feature: the firewall lets the Router Manager in on the internal interface.
+
+  * While vpn-router-manager is installed, vpn-router-setup opens its port,
+    port in /etc/vpn-router-manager/manager.json or 8090, on the internal
+    interface. Purging the package removes the rule.
+
+ -- Slawomir Koszewski <slawek@koszewscy.waw.pl>  Sat, 24 Oct 2026 13:00:00 +0200
+
 vpn-router (0.5.3-1) unstable; urgency=medium
 
   fix: the status always shows the state of slapd.

debian-package/debian/postrm

@@ -11,10 +11,10 @@ strip_ufw_blocks() {
 
     tmp="$(mktemp)"
     awk '
-        /^# (IPSEC|WIREGUARD|OPENVPN|P2S DNS|WEB|ROUTER FORWARD|ROUTER NAT|ROUTER MSS) RULES START$/ {
+        /^# (IPSEC|WIREGUARD|OPENVPN|P2S DNS|WEB|MANAGER|ROUTER FORWARD|ROUTER NAT|ROUTER MSS) RULES START$/ {
             skip = 1; pending = 0; next
         }
-        /^# (IPSEC|WIREGUARD|OPENVPN|P2S DNS|WEB|ROUTER FORWARD|ROUTER NAT|ROUTER MSS) RULES END$/ {
+        /^# (IPSEC|WIREGUARD|OPENVPN|P2S DNS|WEB|MANAGER|ROUTER FORWARD|ROUTER NAT|ROUTER MSS) RULES END$/ {
             skip = 0; next
         }
         skip { next }

debian-package/src/usr/lib/vpn-router/setup

@@ -31,6 +31,11 @@ UFW_DEFAULTS = pathlib.Path('/etc/default/ufw')
 WG_DIR       = pathlib.Path('/etc/wireguard')
 WEB_STATE    = pathlib.Path('/run/vpn-router/web.json')
 
+#: The Router Manager, vpn-router-manager, when it is installed, and its settings.
+MANAGER        = pathlib.Path('/usr/lib/vpn-router-manager/manager')
+MANAGER_CONFIG = pathlib.Path('/etc/vpn-router-manager/manager.json')
+MANAGER_PORT   = 8090
+
 FILTER_ANCHOR = '# End required lines'
 
 #: Configuration options left out wherever the configuration is shown.
@@ -42,6 +47,7 @@ BLOCKS = (
     ('# OPENVPN RULES START',       '# OPENVPN RULES END'),
     ('# P2S DNS RULES START',       '# P2S DNS RULES END'),
     ('# WEB RULES START',           '# WEB RULES END'),
+    ('# MANAGER RULES START',       '# MANAGER RULES END'),
     ('# ROUTER FORWARD RULES START', '# ROUTER FORWARD RULES END'),
     ('# ROUTER NAT RULES START',    '# ROUTER NAT RULES END'),
     ('# ROUTER MSS RULES START',    '# ROUTER MSS RULES END'),
@@ -129,6 +135,15 @@ def is_configured(ctx):
                 vpnrouter.openvpn_ready(ctx)))
 
 
+def manager_port():
+    """The port of the Router Manager: port in its settings, or MANAGER_PORT when it is not set or not a port."""
+    try:
+        port = json.loads(MANAGER_CONFIG.read_text(encoding='utf-8')).get('port')
+    except (OSError, ValueError, AttributeError):
+        return MANAGER_PORT
+    return port if isinstance(port, int) and not isinstance(port, bool) and 1 <= port <= 65535 else MANAGER_PORT
+
+
 def filter_block(ctx):
     lines = [
         '',
@@ -185,6 +200,15 @@ def filter_block(ctx):
             '# WEB RULES END',
         ]
 
+    if MANAGER.exists() and ctx['int_iface']:
+        port = manager_port()
+        lines += [
+            '',
+            '# MANAGER RULES START',
+            f'-A ufw-before-input -i {ctx["int_iface"]} -p tcp --dport {port} -j ACCEPT',
+            '# MANAGER RULES END',
+        ]
+
     if vpnrouter.routing_ready(ctx):
         lines += ['', '# ROUTER FORWARD RULES START']
         for subnet in ctx['local_cidr_list']: