UI improvement

docker/router-dash/app/action_apply_host_overrides.py

@@ -1,3 +1,5 @@
+import ipaddress
+
 from flask import Blueprint, request, redirect, flash
 from auth import require_level
 from config_utils import load_core, save_core, verify_core_hash, apply_msg
@@ -8,6 +10,29 @@ bp = Blueprint('action_apply_host_overrides', __name__)
 VIEW   = '/view/view_host_overrides'
 
 
+def _vlan_networks(core):
+    nets = []
+    for v in core.get('vlans', []):
+        subnet = v.get('subnet', '')
+        mask   = v.get('subnet_mask', '')
+        if subnet and mask:
+            try:
+                nets.append(ipaddress.IPv4Network(f"{subnet}/{mask}", strict=False))
+            except ValueError:
+                pass
+    return nets
+
+
+def _ip_in_vlan(ip_str, core):
+    """Return True if ip_str falls within at least one configured VLAN subnet."""
+    try:
+        addr = ipaddress.IPv4Address(ip_str)
+    except ValueError:
+        return False
+    nets = _vlan_networks(core)
+    return not nets or any(addr in net for net in nets)
+
+
 def _row_index():
     try:
         return int(request.form.get('row_index', ''))
@@ -37,6 +62,10 @@ def add_host_override():
         return redirect(VIEW)
 
     core = load_core()
+    if not _ip_in_vlan(ip, core):
+        flash('IP address does not fall within any configured VLAN subnet.', 'error')
+        return redirect(VIEW)
+
     core.setdefault('host_overrides', []).append({
         'description': description,
         'host':        host,
@@ -94,6 +123,10 @@ def edit_host_override():
         return redirect(VIEW)
 
     core  = load_core()
+    if not _ip_in_vlan(ip, core):
+        flash('IP address does not fall within any configured VLAN subnet.', 'error')
+        return redirect(VIEW)
+
     items = core.get('host_overrides', [])
     if idx < 0 or idx >= len(items):
         flash('Entry not found.', 'error')