The portal derives the device MAC instead of trusting the caller

src/Services/UnifiApiClient.php

@@ -253,6 +253,24 @@ class UnifiApiClient
         return ! empty($data);
     }
 
+    /**
+     * The client currently holding this IP, or null.
+     *
+     * Reads the cached client list rather than querying per IP: the portal calls
+     * this once per connection attempt, and a class arriving at once would
+     * otherwise be one controller round trip each.
+     */
+    public function findClientByIp(string $ip): ?array
+    {
+        foreach ($this->getActiveClients() as $client) {
+            if (($client['ip'] ?? null) === $ip) {
+                return $client;
+            }
+        }
+
+        return null;
+    }
+
     public function kickClient(string $mac): array
     {
         Cache::forget('unifi:clients');