Technical Report — Wi-Fi Scan at “Korman Vilares Resort”

🎯 Objective

In this report we show how we perform a Wi-Fi network scan to check:

  • Which devices (antennas, mobiles, PCs) are connected.
  • Which services and ports are active.
  • That firewall filtering and security are working properly.

🔍 What is a network scan?

A network scan is a process that allows us to discover and analyze devices connected to a given IP range. For this task, we use two complementary tools:

1) Host discovery (ARP Sweep) 🖧

  • Tool: netdiscover
  • Function: detects live IPs in the LAN by resolving their MAC addresses.
  • Results in our Wi-Fi:
    • ✅ Antennas: 10.10.0.12, 10.10.0.14, 10.10.0.16.
    • ✅ Gateway/IPFire: 10.10.0.1.
    • ✅ Guest client: 10.10.0.4 (Pixel 3a XL).
    • ✅ Other temporary devices (10.10.0.6, 10.10.0.8).

📌 Command used:

netdiscover -r 10.10.0.0/24

2) Port and service scanning 🔓

  • Tool: nmap (with Zenmap GUI).
  • Function: performs a SYN Scan to discover open ports, active services, and OS fingerprints.
  • Expected results in our network:
    • Web ports 80/443 active on gateway and antennas.
    • DNS (53/tcp/udp) active on gateway.
    • Auxiliary services like 3128 (proxy/captive helper).

📌 Command used:

nmap -T4 -A -v 10.10.0.0/24

✅ Conclusion: Everything works as expected → gateway responds properly, antennas are accessible, and no unusual services are open on client devices.


🧱 Security and captive portal

The network is secured with a deny-by-default model:

  • 🌐 HTTP (80) traffic redirected to the welcome portal.
  • 🔒 HTTPS (443) allowed only to authorized domains.
  • 📡 Antennas always whitelisted.
  • 🔄 VPN tun1 as the main outgoing path.
  • 🛑 DNS traffic blocked unless it passes through the official resolver.

🗂️ Scripts in /root ready to deploy ⚡

We created these scripts to cover different needs. Quick description:

  • add-whitelist.sh → Adds a domain/IP to the whitelist.
  • block-dns.sh → Blocks unauthorized DNS resolutions.
  • bridge0/ → Bridge network configuration.
  • create-ipset.sh → Creates ipset lists for filtering.
  • drop-iptables.sh → Drops all traffic (full lockdown).
  • firewall-portal.sh → Activates the main captive portal.
  • firewall-portal-undo.sh → Reverts portal rules.
  • iptables.sh → Base iptables configuration.
  • Kor_ipfire2_Swiss.ovpn → OpenVPN profile to Switzerland.
  • maps-allow-hosts.sh → Whitelist for OpenStreetMap tiles.
  • qemu-kali/ → Config for Kali Linux VM.
  • start-network.sh → Brings up tun1 and applies firewall rules.
  • tap0.sh → Creates a TAP interface.
  • tidio-allow.sh → Allows Tidio chat connections.
  • tidio-allow-undo.sh → Removes Tidio from whitelist.
  • tun-service.sh → Controls OpenVPN service (start/stop).
  • welcome-iptables.sh → Redirects HTTP to welcome page.
  • whitelist-host.sh → Quickly whitelists an IP.
  • whitelist-osm-maps.sh → Specific whitelist for OSM map servers.

✅ Current status

  • 📡 Antennas active and working correctly.
  • 🔑 Gateway responding with expected open ports.
  • 📱 Guest client detected and controlled.
  • ⚙️ Scripts ready for immediate adjustments.

🚀 Conclusion

With this system of monitoring and automation, the Wi-Fi network at Korman Vilares Resort remains secure, controlled, and efficient, ensuring reliable connectivity for users and stability for internal services.