OpenWrt在场侦测

• OpenWrt: 192.168.1.1
• Clients: A, B, C ……

首先安装必要的软件包，并且允许匿名访问API

ubus call hostapd.wlan0 get_clients
opkg install uhttpd-mod-ubus jq
vi /usr/share/rpcd/acl.d/unauthenticated.json
service rpcd restart
service uhttpd restart

{
  "unauthenticated": {
    "description": "Access controls for unauthenticated requests",
    "read": {
      "ubus": {
        "session": [
          "access",
          "login"
        ],
        "hostapd.*": [
          "get_clients"
        ]
      }
    }
  }
}

用下面的命令侦测某个设备是否在场

curl -s http://127.0.0.1/ubus -d @payload.json |
  jq -e '.result[1].clients|keys|contains(["aa:aa:aa:aa:aa:aa"])'

{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "call",
  "params": [
    "00000000000000000000000000000000",
    "hostapd.wlan0",
    "get_clients",
    {}
  ]
}

{
  "jsonrpc": "2.0",
  "id": 1,
  "result": [
    0,
    {
      "freq": 2437,
      "clients": {
        "aa:aa:aa:aa:aa:aa": {...},
        "bb:bb:bb:bb:bb:bb": {...},
        "cc:cc:cc:cc:cc:cc": {...}
      }
    }
  ]
}

发布/订阅MQTT消息Broker

# install
opkg install mosquitto-client-ssl

# publish
curl -s http://127.0.0.1/ubus -d @payload.json | jq -c '.result[1].clients|keys|sort' | mosquitto_pub mosquitto_pub -h broker.hivemq.com -t openwrt/clients -l

# subscribe
mosquitto_sub -v -h broker.hivemq.com -t openwrt/clients

参考：https://openwrt.org/docs/techref/ubus