// Handle switch connected event
func (self *OFSwitch) switchConnected() {
self.app.SwitchConnected(self)
// Send new feature request
self.Send(openflow13.NewFeaturesRequest())
// FIXME: This is too fragile. Create a periodic timer
// Start the periodic echo request loop
self.Send(openflow13.NewEchoRequest())
}
// Handle TCP connection from the switch
func (c *Controller) handleConnection(conn net.Conn) {
stream := util.NewMessageStream(conn, c)
log.Println("New connection..")
// Send ofp 1.3 Hello by default
h, err := common.NewHello(4)
if err != nil {
return
}
stream.Outbound <- h
for {
select {
// Send hello message with latest protocol version.
case msg := <-stream.Inbound:
switch m := msg.(type) {
// A Hello message of the appropriate type
// completes version negotiation. If version
// types are incompatable, it is possible the
// connection may be servered without error.
case *common.Hello:
if m.Version == openflow13.VERSION {
log.Infoln("Received Openflow 1.3 Hello message")
// Version negotiation is
// considered complete. Create
// new Switch and notifiy listening
// applications.
stream.Version = m.Version
stream.Outbound <- openflow13.NewFeaturesRequest()
} else {
// Connection should be severed if controller
// doesn't support switch version.
log.Println("Received unsupported ofp version", m.Version)
stream.Shutdown <- true
}
// After a vaild FeaturesReply has been received we
// have all the information we need. Create a new
// switch object and notify applications.
case *openflow13.SwitchFeatures:
log.Printf("Received ofp1.3 Switch feature response: %+v", *m)
// Create a new switch and handover the stream
NewSwitch(stream, m.DPID, c.app)
// Let switch instance handle all future messages..
return
// An error message may indicate a version mismatch. We
// disconnect if an error occurs this early.
case *openflow13.ErrorMsg:
log.Warnf("Received ofp1.3 error msg: %+v", *m)
stream.Shutdown <- true
}
case err := <-stream.Error:
// The connection has been shutdown.
log.Println(err)
return
case <-time.After(time.Second * 3):
// This shouldn't happen. If it does, both the controller
// and switch are no longer communicating. The TCPConn is
// still established though.
log.Warnln("Connection timed out.")
return
}
}
}