// loop for sending messages from channel to frpc func msgSender(s *server.ProxyServer, c *conn.Conn, msgSendChan chan interface{}) { for { msg, ok := <-msgSendChan if !ok { break } buf, _ := json.Marshal(msg) err := c.Write(string(buf) + "\n") if err != nil { log.Warn("ProxyName [%s], write to client error, proxy exit", s.Name) s.Close() break } } }
// loop for reading messages from frpc after control connection is established func msgReader(s *server.ProxyServer, c *conn.Conn, msgSendChan chan interface{}) error { // for heartbeat var heartbeatTimeout bool = false timer := time.AfterFunc(time.Duration(server.HeartBeatTimeout)*time.Second, func() { heartbeatTimeout = true s.Close() log.Error("ProxyName [%s], client heartbeat timeout", s.Name) }) defer timer.Stop() for { buf, err := c.ReadLine() if err != nil { if err == io.EOF { log.Warn("ProxyName [%s], client is dead!", s.Name) return err } else if c == nil || c.IsClosed() { log.Warn("ProxyName [%s], client connection is closed", s.Name) return err } log.Warn("ProxyName [%s], read error: %v", s.Name, err) continue } cliReq := &msg.ControlReq{} if err := json.Unmarshal([]byte(buf), &cliReq); err != nil { log.Warn("ProxyName [%s], parse msg from frpc error: %v : %s", s.Name, err, buf) continue } switch cliReq.Type { case consts.HeartbeatReq: log.Debug("ProxyName [%s], get heartbeat", s.Name) timer.Reset(time.Duration(server.HeartBeatTimeout) * time.Second) heartbeatRes := &msg.ControlRes{ Type: consts.HeartbeatRes, } msgSendChan <- heartbeatRes default: log.Warn("ProxyName [%s}, unsupport msgType [%d]", s.Name, cliReq.Type) } } return nil }
// connection from every client and server func controlWorker(c *conn.Conn) { // if login message type is NewWorkConn, don't close this connection var closeFlag bool = true var s *server.ProxyServer defer func() { if closeFlag { c.Close() if s != nil { s.Close() } } }() // get login message buf, err := c.ReadLine() if err != nil { log.Warn("Read error, %v", err) return } log.Debug("Get msg from frpc: %s", buf) cliReq := &msg.ControlReq{} if err := json.Unmarshal([]byte(buf), &cliReq); err != nil { log.Warn("Parse msg from frpc error: %v : %s", err, buf) return } // login when type is NewCtlConn or NewWorkConn ret, info := doLogin(cliReq, c) s, ok := server.ProxyServers[cliReq.ProxyName] if !ok { log.Warn("ProxyName [%s] is not exist", cliReq.ProxyName) return } // if login type is NewWorkConn, nothing will be send to frpc if cliReq.Type != consts.NewWorkConn { cliRes := &msg.ControlRes{ Type: consts.NewCtlConnRes, Code: ret, Msg: info, } byteBuf, _ := json.Marshal(cliRes) err = c.Write(string(byteBuf) + "\n") if err != nil { log.Warn("ProxyName [%s], write to client error, proxy exit", s.Name) time.Sleep(1 * time.Second) return } } else { closeFlag = false return } // if login failed, just return if ret > 0 { return } // create a channel for sending messages msgSendChan := make(chan interface{}, 1024) go msgSender(s, c, msgSendChan) go noticeUserConn(s, msgSendChan) // loop for reading control messages from frpc and deal with different types msgReader(s, c, msgSendChan) close(msgSendChan) log.Info("ProxyName [%s], I'm dead!", s.Name) return }