feature: vpn-config-edit shows and changes the router's configuration.

ADR.md

@@ -42,9 +42,15 @@ the package depends on, and no web framework. It listens on `web.port`, 7081 by
 address of the internal interface, of the external interface or of both, as `web.listen` sets
 (`internal`, `external` or `both`, the default), with a server for each address, and is on
 unless `web.enabled` is `false` (ADR-7). `/` is for people, in plain text for `curl` and `wget`
-and as a Tailwind CSS page for a browser, and `/status` is the same status as JSON. It shows the
-state of the services, the package version and the state of the site-to-site, road-warrior,
-OpenVPN and WireGuard features, and nothing from the configuration. `vpn-router-setup` opens the
+and as a Tailwind CSS page for a browser, and `/status` is the same status as JSON. Both show as
+much as `web.status_content` says, since the router is reachable from the internet and the
+operator decides how much it tells strangers: `basic`, the default because it tells the least,
+the overall status and the Client IP, `standard` also the package versions and the number of
+active and other services, and `full` also each service and the state of the site-to-site, road-warrior, OpenVPN and
+WireGuard features. The Client IP is the address the request came from, through the trusted
+proxies, so a person can see the address the router sees. Nothing comes from the configuration.
+`/status` names its content, so clients such as manage-ui and the Router Manager show what it
+has. `vpn-router-setup` opens the
 port on both interfaces in UFW, so the choice of `web.listen` is made by the service alone, and
 writes the features and the facts it resolves to `/run/vpn-router/web.json`.
 

README.md

@@ -127,7 +127,8 @@ must have the type shown below; an unknown section or setting is an error.
 | `web` | `listen` | string | `both` | The interfaces the status web service listens on: `internal`, `external` or `both` |
 | `web` | `port` | integer | `7081` | TCP port of the status web service |
 | `web` | `database` | string | | A PostgreSQL connection string for the refresh tokens; without it, the `vpn-router` database on this host that the web service creates |
-| `web` | `trusted_proxies` | list | the address the call came in on | Addresses whose `X-Forwarded-For` header names the client for the `/auth` rate limit |
+| `web` | `trusted_proxies` | list | the address the call came in on | Addresses whose `X-Forwarded-For` header names the client for the `/auth` rate limit and the Client IP of the status |
+| `web` | `status_content` | string | `basic` | What `/` and `/status` show: `basic`, `standard` or `full` (see Status web service) |
 | `https` | `enabled` | boolean | `true` | Caddy serves the status web service and the Router Manager over HTTPS for `wan.local_fqdn` |
 | `https` | `email` | string | | The e-mail address of the Let's Encrypt account |
 | `https` | `web_port` | integer | `7444` | HTTPS port of the status web service |
@@ -239,6 +240,24 @@ vpn-router-setup` applies a changed configuration while Docker runs. With `docke
 `on`, the service fails when Docker is not installed or its daemon is not running; with
 `off` it removes the rules.
 
+## Editing the configuration
+
+`vpn-config-edit`, run as root, shows and changes `/etc/vpn-router/vpn-router.json`:
+
+```sh
+vpn-config-edit show
+vpn-config-edit set web.status_content standard
+vpn-config-edit set web.port 7082
+vpn-config-edit set web.trusted_proxies 127.0.0.1,10.0.0.4
+```
+
+`show` prints the file as indented JSON and does not change it. `set` takes a setting as
+`section.option` and converts the value to the setting's type: a whole number, `true` or
+`false`, a list separated by commas (an empty value is an empty list), or a string; an unknown
+setting is refused. It checks the whole configuration as `vpn-router-setup` does, and only then
+writes the file, indented, with mode 0600, and reminds that `vpn-router-setup` applies it. A
+refused request exits with status 2, any other failure with 1.
+
 ## Applying changes
 
 ```sh
@@ -500,7 +519,19 @@ modules shipped with the package; the configuration file accepts any module inst
 The `vpn-router-web` service shows the state of the router on the addresses of the interfaces
 `web.listen` names, the internal, the external or both (the default), and on `127.0.0.1`, where
 Caddy calls it (see HTTPS), with `web.port` (7081 by default). Its pages `/` and `/status` need no authentication and show no
-configuration: no key, identity, address or subnet.
+configuration: no key, identity, subnet, or address but the client's. They show as much as
+`web.status_content` says, read at each request:
+
+| `status_content` | `/` and `/status` show |
+|---|---|
+| `basic` (default) | The overall status (`ok` or `degraded`), the time and the Client IP |
+| `standard` | Also the `vpn-router` version, the `vpn-router-manager` version or that it is not installed, and the number of active services and of services in any other state, without their names |
+| `full` | Also each service and its state, Docker, and the state of site-to-site, road-warrior, OpenVPN and WireGuard |
+
+The Client IP is the address the request came from: the last entry of `X-Forwarded-For` for a
+request from one of `web.trusted_proxies`, by default the address the request came in on, so
+behind Caddy or a Router Manager on the router it is the browser's. `/status` names the content in
+`content` and the Client IP in `client_ip`; `/` keeps the time and the link to `/status`.
 
 The service first makes its signing key and the refresh tokens' database, retrying every 15
 seconds, for example while PostgreSQL is not running yet, and logs each failure; then it listens.

debian-package/debian/changelog

@@ -1,3 +1,41 @@
+vpn-router (0.15.0-1) unstable; urgency=medium
+
+  feature: vpn-config-edit shows and changes the router's configuration.
+
+  * vpn-config-edit show prints /etc/vpn-router/vpn-router.json as
+    indented JSON.
+  * vpn-config-edit set SECTION.OPTION VALUE converts the value to the
+    setting's type, checks the whole configuration as vpn-router-setup
+    does, writes the file indented with mode 0600, and reminds that
+    vpn-router-setup applies it.
+
+ -- Slawomir Koszewski <slawek@koszewscy.waw.pl>  Sun, 25 Oct 2026 18:00:00 +0200
+
+vpn-router (0.14.1-1) unstable; urgency=medium
+
+  fix: web.status_content is basic by default.
+
+  * Without web.status_content, or with a value that is not allowed, /
+    and /status show only the overall status, the time and the Client
+    IP; set it to standard or full to show more.
+
+ -- Slawomir Koszewski <slawek@koszewscy.waw.pl>  Sun, 25 Oct 2026 17:00:00 +0200
+
+vpn-router (0.14.0-1) unstable; urgency=medium
+
+  feature: the status page shows the Client IP, and web.status_content sets how much it shows.
+
+  * / and /status show the Client IP, the address the request came from:
+    the last X-Forwarded-For entry for a request from a trusted proxy, so
+    behind Caddy or the Router Manager the browser's; /status has it as
+    client_ip.
+  * web.status_content sets what / and /status show: basic the overall
+    status, the time and the Client IP; standard also the package
+    versions and the number of active and failed services; full, the
+    default, everything as before. /status names it in content.
+
+ -- Slawomir Koszewski <slawek@koszewscy.waw.pl>  Sun, 25 Oct 2026 16:00:00 +0200
+
 vpn-router (0.13.0-1) unstable; urgency=medium
 
   feature: Caddy serves the status page and the Router Manager over HTTPS with a certificate from Let's Encrypt.

debian-package/debian/install

@@ -9,6 +9,7 @@ src/usr/lib/vpn-router/openvpn-same-user              usr/lib/vpn-router/
 src/usr/sbin/vpn-router-user                          usr/sbin/
 src/usr/sbin/vpn-router-group                         usr/sbin/
 src/usr/sbin/vpn-router-token                         usr/sbin/
+src/usr/sbin/vpn-config-edit                          usr/sbin/
 src/usr/lib/vpn-router/simple-ca                      usr/lib/vpn-router/
 src/usr/lib/vpn-router/configure                      usr/lib/vpn-router/
 src/usr/lib/vpn-router/docker-rules                   usr/lib/vpn-router/

debian-package/src/usr/lib/vpn-router/vpnrouter.py

@@ -54,13 +54,17 @@ SCHEMA = {
     'wireguard':  {'enabled': False, 'address': '', 'listen_port': 51820},
     'openvpn':    {'enabled': False, 'address_pool': '', 'port': 1194, 'protocol': 'udp'},
     'docker':     {'mode': 'auto', 'exposed_ports': []},
-    'web':        {'enabled': True, 'listen': DEFAULT_LISTEN, 'port': 7081, 'database': '', 'trusted_proxies': []},
+    'web':        {'enabled': True, 'listen': DEFAULT_LISTEN, 'port': 7081, 'database': '', 'trusted_proxies': [],
+                   'status_content': 'basic'},
     'https':      {'enabled': True, 'email': '', 'web_port': 7444, 'manager_port': 7443},
 }
 
 #: The port of Let's Encrypt's HTTP challenge, which Caddy answers while HTTPS is on.
 ACME_HTTP_PORT = 80
 
+#: What / and /status of the web service show, web.status_content, from the least to the most.
+STATUS_CONTENTS = ('basic', 'standard', 'full')
+
 DOCKER_MODES = ('auto', 'on', 'off')
 
 OPENVPN_PROTOCOLS = ('udp', 'tcp')
@@ -268,6 +272,11 @@ def validate(cfg):
         raise ConfigError(
             f'web.listen: {web_listen!r} is not one of {", ".join(LISTEN_CHOICES)}')
 
+    status_content = _get(cfg, 'web', 'status_content')
+    if status_content not in STATUS_CONTENTS:
+        raise ConfigError(
+            f'web.status_content: {status_content!r} is not one of {", ".join(STATUS_CONTENTS)}')
+
     https_ports = []
     for option in ('web_port', 'manager_port'):
         port = _get(cfg, 'https', option)

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

@@ -29,10 +29,13 @@ served (404) while the key does not exist. /auth is limited to AUTH_LIMIT calls
 address in AUTH_WINDOW seconds; the address of a call from one of web.trusted_proxies, by
 default the address the call came in on, is the last entry of its X-Forwarded-For header.
 
-/ and /status show only the status: whether the services run, the package version and the
-installed version of vpn-router-manager (manager_version, null when it is not installed), whether
-Docker is installed, and the state of site-to-site, road-warrior (IPsec P2S), OpenVPN and
-WireGuard. No configuration data, key or address is shown.
+/ and /status show only the status, as much as web.status_content says (see shown): basic, the
+default, the overall status, the time and the client's address (its address as for the rate limit
+below); standard also the package version, the installed version of vpn-router-manager
+(manager_version, null when it is not installed) and the number of active and other services; full
+whether each service runs, whether Docker is installed, and the state of site-to-site, road-warrior
+(IPsec P2S), OpenVPN and WireGuard. No configuration data or key is shown, and no address but the
+client's.
 
 The service first initializes, without listening: it makes the signing key and the refresh
 tokens' database (vpnrouter_auth), retrying every INIT_RETRY_SECONDS until both are ready and
@@ -289,6 +292,26 @@ def collect(state):
     return status
 
 
+def shown(status, content, client):
+    """The status document as web.status_content shows it to the client at its address.
+
+    Every content has status, time and client_ip, the client's address, and content, which one it is: basic nothing
+    more; standard adds version, manager_version and services, the number of active units and of units in every
+    other state; full adds the whole status document of collect. Content that is not one of
+    vpnrouter.STATUS_CONTENTS, or not set, is basic.
+    """
+    if content not in vpnrouter.STATUS_CONTENTS:
+        content = 'basic'
+    if content == 'full':
+        return {**status, 'content': content, 'client_ip': client}
+    document = {'status': status['status'], 'content': content, 'time': status['time'], 'client_ip': client}
+    if content == 'standard':
+        active = sum(1 for value in status['units'].values() if value == 'active')
+        document.update(version=status['version'], manager_version=status['manager_version'],
+                        services={'active': active, 'failed': len(status['units']) - active})
+    return document
+
+
 def lines_of(*args):
     """The output lines of a command, or None when it fails."""
     result = run(*args)
@@ -346,13 +369,20 @@ def details(state):
 
 
 def text_of(status):
-    """The status for people, as plain text."""
-    lines = ['VPN Router', f'Status: {status["status"]}', f'Version: {status["version"] or "unknown"}', '']
-    lines.append(f'Router Manager: {status["manager_version"] or "not installed"}')
-    lines += [f'{name}: {value}' for name, value in status['units'].items()]
-    docker = status['docker']
-    lines.append('Docker: not installed' if not docker['installed']
-                 else f'Docker: installed, service {docker["service"]}, rules {docker["rules"]}')
+    """The status document of shown for people, as plain text: a header, a blank line, then name: value lines."""
+    lines = ['VPN Router', f'Status: {status["status"]}']
+    if 'version' in status:
+        lines.append(f'Version: {status["version"] or "unknown"}')
+    lines += ['', f'Client IP: {status["client_ip"]}']
+    if 'manager_version' in status:
+        lines.append(f'Router Manager: {status["manager_version"] or "not installed"}')
+    if 'services' in status:
+        lines.append(f'Services: {status["services"]["active"]} active, {status["services"]["failed"]} failed')
+    lines += [f'{name}: {value}' for name, value in status.get('units', {}).items()]
+    if 'docker' in status:
+        docker = status['docker']
+        lines.append('Docker: not installed' if not docker['installed']
+                     else f'Docker: installed, service {docker["service"]}, rules {docker["rules"]}')
     if 'site_to_site' in status:
         value = status['site_to_site']['established']
         lines.append(f'Site to site: {"unknown" if value is None else "established" if value else "not established"}')
@@ -376,11 +406,12 @@ def text_of(status):
 
 
 def html_of(status):
-    """The status for a browser, as a page styled with Tailwind CSS."""
+    """The status document of shown for a browser, as a page styled with Tailwind CSS."""
     colour = 'bg-emerald-600 dark:bg-emerald-700' if status['status'] == 'ok' else 'bg-amber-600 dark:bg-amber-700'
-    # Each "name: value" line of the text is a row; indented lines, such as WireGuard peers, are indented here too.
+    version = f', version {status["version"] or "unknown"}' if 'version' in status else ''
+    # Each "name: value" line after the header of the text is a row; indented lines, such as WireGuard peers, are indented here too.
     rows = []
-    for line in text_of(status).splitlines()[4:]:
+    for line in text_of(status).split('\n\n', 1)[1].splitlines():
         if not line:
             continue
         name, _, value = line.partition(': ')
@@ -404,7 +435,7 @@ def html_of(status):
       <div class="overflow-hidden rounded-2xl border border-slate-200 bg-white shadow-lg dark:border-slate-700 dark:bg-slate-800">
         <div class="{colour} px-6 py-4 text-white">
           <h1 class="text-xl font-semibold">VPN Router</h1>
-          <p class="mt-1 text-sm">Status: {escape(status['status'])}, version {escape(status['version'] or 'unknown')}</p>
+          <p class="mt-1 text-sm">Status: {escape(status['status'] + version)}</p>
         </div>
         <div class="px-6 py-4">
           <table class="w-full text-sm"><tbody>{body}</tbody></table>
@@ -718,14 +749,15 @@ class Handler(BaseHTTPRequestHandler):
             body, kind = json.dumps(document, indent=2).encode() + b'\n', 'application/json'
         elif self.command not in ('GET', 'HEAD'):
             body, kind, code = b'Method not allowed\n', 'text/plain; charset=utf-8', 405
-        elif path == '/status':
-            body, kind, code = json.dumps(self.status(), indent=2).encode() + b'\n', 'application/json', 200
-        elif path == '/':
+        elif path in ('/status', '/'):
+            document = shown(self.status(), section(read_json(CONFIG_FILE), 'web').get('status_content'), self.client())
             agent = self.headers.get('User-Agent', '').lower()
-            if 'curl' in agent or 'wget' in agent:
-                body, kind = text_of(self.status()).encode(), 'text/plain; charset=utf-8'
+            if path == '/status':
+                body, kind = json.dumps(document, indent=2).encode() + b'\n', 'application/json'
+            elif 'curl' in agent or 'wget' in agent:
+                body, kind = text_of(document).encode(), 'text/plain; charset=utf-8'
             else:
-                body, kind = html_of(self.status()).encode(), 'text/html; charset=utf-8'
+                body, kind = html_of(document).encode(), 'text/html; charset=utf-8'
             code = 200
         else:
             body, kind, code = b'Not found\n', 'text/plain; charset=utf-8', 404

debian-package/src/usr/sbin/vpn-config-edit

@@ -0,0 +1,129 @@
+#!/usr/bin/python3
+"""Show and change the router's configuration, /etc/vpn-router/vpn-router.json.
+
+show prints the file as indented JSON; the file is not changed. set takes a setting as
+section.option, such as web.port, and a value, which it converts to the type the package's
+schema (vpnrouter.SCHEMA) gives the setting: a whole number, true or false, a list of strings
+separated by commas (an empty value is an empty list), or a string. The configuration with the
+new value is checked as vpn-router-setup checks it, and only then written, indented, with mode
+0600; vpn-router-setup applies it at its next run, which set reminds of. A failure is a message
+on standard error; the exit status is 2 for an invalid request and 1 for any other failure.
+-h or --help shows the options.
+
+  vpn-config-edit show
+  vpn-config-edit set SECTION.OPTION VALUE
+"""
+
+import argparse
+import json
+import os
+import sys
+import tempfile
+
+sys.path.insert(0, '/usr/lib/vpn-router')
+
+import vpnrouter
+
+
+class Failure(Exception):
+    """A request that cannot be done; status is 2 invalid, 1 other."""
+
+    def __init__(self, message, status=1):
+        super().__init__(message)
+        self.status = status
+
+
+class Parser(argparse.ArgumentParser):
+    """An argument parser whose errors are Failures with status 2."""
+
+    def error(self, message):
+        raise Failure(f'{message}; see {self.prog} --help', 2)
+
+
+def read():
+    """The settings in the configuration file, without the defaults; {} when the file does not exist."""
+    try:
+        data = json.loads(vpnrouter.CONFIG_FILE.read_text(encoding='utf-8'))
+    except FileNotFoundError:
+        return {}
+    except ValueError as exc:
+        raise Failure(f'cannot parse {vpnrouter.CONFIG_FILE}: {exc}')
+    if not isinstance(data, dict) or not all(isinstance(options, dict) for options in data.values()):
+        raise Failure(f'cannot parse {vpnrouter.CONFIG_FILE}: it is not an object of sections')
+    return data
+
+
+def converted(key, text):
+    """The value of text for the setting key, section.option, of the type the schema gives it."""
+    section, _, option = key.partition('.')
+    if section not in vpnrouter.SCHEMA or option not in vpnrouter.SCHEMA[section]:
+        raise Failure(f'{key}: unknown setting; settings are section.option, such as web.port', 2)
+    kind = type(vpnrouter.SCHEMA[section][option])
+    if kind is bool:
+        if text not in ('true', 'false'):
+            raise Failure(f'{key} takes true or false', 2)
+        return text == 'true'
+    if kind is int:
+        try:
+            return int(text)
+        except ValueError:
+            raise Failure(f'{key} takes a whole number', 2)
+    if kind is list:
+        return [item.strip() for item in text.split(',') if item.strip()]
+    return text
+
+
+def write(data):
+    """Write the settings, indented, with mode 0600, replacing the file in one step."""
+    directory = vpnrouter.CONFIG_FILE.parent
+    descriptor, name = tempfile.mkstemp(dir=directory, prefix='.vpn-router.json.')
+    try:
+        with os.fdopen(descriptor, 'w', encoding='utf-8') as handle:
+            handle.write(json.dumps(data, indent=2) + '\n')
+        os.chmod(name, 0o600)
+        os.replace(name, vpnrouter.CONFIG_FILE)
+    except OSError:
+        os.unlink(name)
+        raise
+
+
+def main(argv):
+    try:
+        parser = Parser(prog='vpn-config-edit', description='Show and change the router configuration.')
+        commands = parser.add_subparsers(dest='command', required=True, parser_class=Parser)
+        commands.add_parser('show', help='print the configuration as indented JSON')
+        setter = commands.add_parser('set', help='set a setting and write the configuration')
+        setter.add_argument('key', metavar='SECTION.OPTION', help='the setting, such as web.port')
+        setter.add_argument('value', metavar='VALUE', help='its value; a list separated by commas')
+        options = parser.parse_args(argv)
+
+        data = read()
+        if options.command == 'show':
+            print(json.dumps(data, indent=2))
+            return 0
+
+        section, _, option = options.key.partition('.')
+        value = converted(options.key, options.value)
+        data.setdefault(section, {})[option] = value
+        # The configuration as vpn-router-setup reads it: the defaults with the file's settings.
+        candidate = {name: dict(defaults) for name, defaults in vpnrouter.SCHEMA.items()}
+        for name, settings in data.items():
+            candidate.setdefault(name, {}).update(settings)
+        try:
+            vpnrouter.validate(candidate)
+        except vpnrouter.ConfigError as exc:
+            raise Failure(str(exc), 2)
+        write(data)
+    except Failure as failure:
+        print(f'vpn-config-edit: {failure}', file=sys.stderr)
+        return failure.status
+    except OSError as exc:
+        print(f'vpn-config-edit: {exc}', file=sys.stderr)
+        return 1
+    print(f'{options.key} set to {json.dumps(value)} in {vpnrouter.CONFIG_FILE}.')
+    print('Apply it with: systemctl restart vpn-router-setup')
+    return 0
+
+
+if __name__ == '__main__':
+    sys.exit(main(sys.argv[1:]))

debian-package/src/usr/share/doc/vpn-router/vpn-router.json.example

@@ -48,7 +48,8 @@
     "listen": "both",
     "port": 7081,
     "database": "",
-    "trusted_proxies": []
+    "trusted_proxies": [],
+    "status_content": "basic"
   },
   "https": {
     "enabled": true,