feature: a VPN user has WireGuard peers, each a device with its public key and IPs, kept in the directory and written into wg0.conf by setup.

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

@@ -38,6 +38,9 @@ SITE_TO_SITE   = SWANCTL_CONF_D / 'site-to-site.conf'
 ROAD_WARRIOR   = SWANCTL_CONF_D / 'road-warrior.conf'
 P2S_FORWARDER  = pathlib.Path('/etc/systemd/resolved.conf.d/p2s-forwarder.conf')
 WG_CONF        = pathlib.Path('/etc/wireguard/wg0.conf')
+#: The lines around the [Peer] sections of the users' WireGuard peers in WG_CONF, which setup writes from the directory.
+WG_PEERS_BEGIN = "# BEGIN WireGuard peers of the users of the router's directory"
+WG_PEERS_END   = "# END WireGuard peers of the users of the router's directory"
 OPENVPN_CONF   = pathlib.Path('/etc/openvpn/server/vpn-router.conf')
 OPENVPN_LDAP   = pathlib.Path('/etc/openvpn/server/vpn-router-ldap.conf')
 
@@ -887,6 +890,8 @@ def build_context(cfg, public_ip=None):
         'wg_enabled':      _get(cfg, 'wireguard', 'enabled'),
         'wg_address':      _get(cfg, 'wireguard', 'address'),
         'wg_listen_port':  _get(cfg, 'wireguard', 'listen_port'),
+        'wg_peers_begin':  WG_PEERS_BEGIN,
+        'wg_peers_end':    WG_PEERS_END,
         'openvpn_enabled': _get(cfg, 'openvpn', 'enabled'),
         'openvpn_pool':    openvpn_pool,
         'openvpn_network': str(openvpn_network.network_address) if openvpn_network else '',
@@ -981,27 +986,38 @@ def render(env, ctx, template_name, dest, mode):
 
 
 def existing_peers(path):
-    """Return the [Peer] sections of an existing WireGuard config.
+    """The block of the users' peers and the [Peer] sections added by hand of an existing WireGuard config, each ''
+    without one.
 
-    Peers are added by the operator by hand, so re-rendering the [Interface]
-    section must not discard them.
+    The block lies between WG_PEERS_BEGIN and WG_PEERS_END; the [Peer] sections outside it are the operator's, which
+    re-rendering the file keeps.
     """
     path = pathlib.Path(path)
     if not path.is_file():
-        return ''
-    lines = path.read_text(encoding='utf-8').splitlines(keepends=True)
+        return '', ''
+    text = path.read_text(encoding='utf-8')
+    block = ''
+    begin, end = text.find(WG_PEERS_BEGIN), text.find(WG_PEERS_END)
+    if begin != -1 and end > begin:
+        block = text[begin:end + len(WG_PEERS_END)]
+        text = text[:begin] + text[end + len(WG_PEERS_END):]
+    lines = text.splitlines(keepends=True)
     for index, line in enumerate(lines):
         if line.strip().lower() == '[peer]':
-            return ''.join(lines[index:])
-    return ''
+            return block, ''.join(lines[index:])
+    return block, ''
 
 
 def render_wg_conf(env, ctx, dest=WG_CONF, mode=0o600):
-    """Render wg0.conf, carrying any operator-defined peers across."""
-    content = env.get_template('wg0.conf.j2').render(ctx)
-    peers = existing_peers(dest)
-    if peers:
-        content = content.rstrip('\n') + '\n\n' + peers
+    """Render wg0.conf: the [Interface], the block of the users' peers of ctx's wg_peers, the block the file holds while
+    wg_peers is None, and the peers the operator added by hand, carried across."""
+    content = env.get_template('wg0.conf.j2').render(ctx).rstrip('\n') + '\n'
+    block, own = existing_peers(dest)
+    if ctx['wg_peers'] is not None:
+        block = env.get_template('wg0-peers.conf.j2').render(ctx).strip('\n') if ctx['wg_peers'] else ''
+    for part in (block, own):
+        if part.strip():
+            content += '\n' + part.strip('\n') + '\n'
 
     dest = pathlib.Path(dest)
     if dest.exists() and dest.read_text(encoding='utf-8') == content:
@@ -1070,6 +1086,13 @@ def configure(cfg=None, public_ip=None):
             notices = [f'the PKI is left as it is: the directory cannot be reached: {exc}']
     for notice in notices:
         warn(notice)
+    # The WireGuard peers of the users; None keeps those of wg0.conf while the directory cannot be reached.
+    ctx['wg_peers'] = None
+    if wg_ready(ctx):
+        try:
+            ctx['wg_peers'] = vpnrouter_ldap.wireguard_peers()
+        except ldap.LDAPError as exc:
+            warn(f'the WireGuard peers of the users are left as they are: the directory cannot be reached: {exc}')
     # What needs the router's own certificates.
     ctx['server_certificate'] = vpnrouter_pki.VPN_SERVER_CERT.is_file()
     for connection in ctx['connections']: