client2server

client2server

Lightweight event forwarder for OpenWrt routers to central server

Overview

Lightweight bash/lua scripts that listen to OpenWrt events (WiFi, DHCP, network) and forward them to a central server via HTTP.

Why This?

• Tiny footprint: ~20KB (vs 5MB+ Go binary)
• No dependencies: Uses built-in OpenWrt tools
• Real-time: Direct ubus/netlink event stream
• Reliable: Can run in procd as a service

Architecture

┌─────────────────┐      HTTP/WebSocket      ┌─────────────────┐
│   OpenWrt       │ ────────────────────────► │ Central Server  │
│   Router       │                           │                 │
│                 │                         │  - Receive     │
│  ubus events   │                         │  - Store        │
│  hostapd_cli  │                         │  - Notify       │
│  dnsmasq      │                         │  - Dashboard   │
└─────────────────┘                         └─────────────────┘

Supported Events

Event Type	Source	Payload
WiFi connect	hostapd	client MAC, signal
WiFi disconnect	hostapd	client MAC, reason
DHCP lease	dnsmasq	IP, MAC, hostname
Interface up/down	netifd	device, state
Network changes	ubus	config changes

Files

File	Purpose
etc/init.d/event-forwarder	Main daemon startup script
etc/config/event-forwarder	UCI configuration
usr/sbin/event-forwarder	Main event listener script
usr/lib/rpcd/event-forwarder	ubus RPC plugin (optional)
README.md	This file

Installation

# Copy to OpenWrt router
scp -r etc root@router:/tmp/
ssh router "mv /tmp/etc/* /etc/"

# Enable service
/etc/init.d/event-forwarder enable
/etc/init.d/event-forwarder start

# Check logs
logread -f -e event-forwarder

Configuration

# Edit config on router
uci set event-forwarder.server.url='https://your-server.com/api/events'
uci set event-forwarder.server.token='your-secret-token'
uci set event-forwarder.general.interval='60'
uci commit event-forwarder
/etc/init.d/event-forwarder restart

Central Server API

Expected endpoint:

POST /api/events
Headers: Authorization: Bearer <token>
Content-Type: application/json

{
  "router_id": "router-hostname-or-id",
  "event_type": "wifi_connect|wifi_disconnect|dhcp_lease|interface_up|config_change",
  "payload": {
    "mac": "AA:BB:CC:DD:EE:FF",
    "ip": "192.168.1.100",
    "hostname": "device-name",
    "signal": -45,
    "device": "wlan0"
  },
  "timestamp": "2026-06-04T18:00:00Z"
}

Security

• Use HTTPS for production
• Store token in /etc/config/event-forwarder
• Consider firewall rules to limit who can POST

License

MIT