package iptables import ( "fmt" "strings" "github.com/Sirupsen/logrus" "github.com/godbus/dbus" ) type IPV string const ( Iptables IPV = "ipv4" Ip6tables IPV = "ipv6" Ebtables IPV = "eb" ) const ( dbusInterface = "org.fedoraproject.FirewallD1" dbusPath = "/org/fedoraproject/FirewallD1" ) // Conn is a connection to firewalld dbus endpoint. type Conn struct { sysconn *dbus.Conn sysobj *dbus.Object signal chan *dbus.Signal } var ( connection *Conn firewalldRunning bool // is Firewalld service running onReloaded []*func() // callbacks when Firewalld has been reloaded ) func FirewalldInit() error { var err error if connection, err = newConnection(); err != nil { return fmt.Errorf("Failed to connect to D-Bus system bus: %v", err) } if connection != nil { go signalHandler() } firewalldRunning = checkRunning() return nil } // New() establishes a connection to the system bus. func newConnection() (*Conn, error) { c := new(Conn) if err := c.initConnection(); err != nil { return nil, err } return c, nil } // Innitialize D-Bus connection. func (c *Conn) initConnection() error { var err error c.sysconn, err = dbus.SystemBus() if err != nil { return err } // This never fails, even if the service is not running atm. c.sysobj = c.sysconn.Object(dbusInterface, dbus.ObjectPath(dbusPath)) rule := fmt.Sprintf("type='signal',path='%s',interface='%s',sender='%s',member='Reloaded'", dbusPath, dbusInterface, dbusInterface) c.sysconn.BusObject().Call("org.freedesktop.DBus.AddMatch", 0, rule) rule = fmt.Sprintf("type='signal',interface='org.freedesktop.DBus',member='NameOwnerChanged',path='/org/freedesktop/DBus',sender='org.freedesktop.DBus',arg0='%s'", dbusInterface) c.sysconn.BusObject().Call("org.freedesktop.DBus.AddMatch", 0, rule) c.signal = make(chan *dbus.Signal, 10) c.sysconn.Signal(c.signal) return nil } func signalHandler() { for signal := range connection.signal { if strings.Contains(signal.Name, "NameOwnerChanged") { firewalldRunning = checkRunning() dbusConnectionChanged(signal.Body) } else if strings.Contains(signal.Name, "Reloaded") { reloaded() } } } func dbusConnectionChanged(args []interface{}) { name := args[0].(string) old_owner := args[1].(string) new_owner := args[2].(string) if name != dbusInterface { return } if len(new_owner) > 0 { connectionEstablished() } else if len(old_owner) > 0 { connectionLost() } } func connectionEstablished() { reloaded() } func connectionLost() { // Doesn't do anything for now. Libvirt also doesn't react to this. } // call all callbacks func reloaded() { for _, pf := range onReloaded { (*pf)() } } // add callback func OnReloaded(callback func()) { for _, pf := range onReloaded { if pf == &callback { return } } onReloaded = append(onReloaded, &callback) } // Call some remote method to see whether the service is actually running. func checkRunning() bool { var zone string var err error if connection != nil { err = connection.sysobj.Call(dbusInterface+".getDefaultZone", 0).Store(&zone) logrus.Infof("Firewalld running: %t", err == nil) return err == nil } return false } // Firewalld's passthrough method simply passes args through to iptables/ip6tables func Passthrough(ipv IPV, args ...string) ([]byte, error) { var output string logrus.Debugf("Firewalld passthrough: %s, %s", ipv, args) if err := connection.sysobj.Call(dbusInterface+".direct.passthrough", 0, ipv, args).Store(&output); err != nil { return nil, err } return []byte(output), nil }