fw.go

package main

import(
    "net/http"
    "encoding/json"
    "os/exec"
    "strconv"
    "fmt"
)

type Session struct {
    Mac      string `json:"max"`
    Ip4      string `json:"ip4"`
    Internet bool   `json:"internet"`
    User     int    `json:"user"`
}

type EventSession struct {
    Action  string  `json:"action"`
    Name    string  `json:"name"`
    Session Session `json:"param"`
}

func echoHandler(w http.ResponseWriter, r *http.Request) {
    if r.Method != "POST" {
        http.Error(w, "Invalid request method.", 405)
        return
    }

    var event EventSession
    err := json.NewDecoder(r.Body).Decode(&event)

    if err != nil {
        http.Error(w, err.Error(), 400)
        return
    }
    fmt.Println("Received event : " + event.Action + " from " + event.Session.Ip4 + " (" + strconv.Itoa(event.Session.User) + ", " + strconv.FormatBool(event.Session.Internet) + ")")
    switch event.Action {
        case "created", "updated" :
            if (event.Session.Internet) && (event.Session.User != 0) {
	        cmd := exec.Command("/sbin/pfctl", "-t", "authorized_users", "-T", "add", event.Session.Ip4)
		if err := cmd.Run(); err != nil {
		    http.Error(w, err.Error(), 500)
		    return
		}
            } else if event.Action == "updated" {
	        cmd := exec.Command("/sbin/pfctl", "-t", "authorized_users", "-T", "delete", event.Session.Ip4)
		if err := cmd.Run() ; err != nil {
		    http.Error(w, err.Error(), 500)
		    return
		}
	    }
        default:
            http.Error(w, "Wrong action type. Supported action are 'created', 'updated'.", 400)
    }
}



func main() {
    http.HandleFunc("/event/session", echoHandler)

    http.ListenAndServe("0.0.0.0:8000", nil)
}