// when frps get one new user connection, send NoticeUserConn message to frpc and accept one new WorkConn later func noticeUserConn(s *server.ProxyServer, msgSendChan chan interface{}) { for { closeFlag := s.WaitUserConn() if closeFlag { log.Debug("ProxyName [%s], goroutine for noticing user conn is closed", s.Name) break } notice := &msg.ControlRes{ Type: consts.NoticeUserConn, } msgSendChan <- notice log.Debug("ProxyName [%s], notice client to add work conn", s.Name) } }
// 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 }
// if success, ret equals 0, otherwise greater than 0 func doLogin(req *msg.ControlReq, c *conn.Conn) (ret int64, info string) { ret = 1 if req.PrivilegeMode && !server.PrivilegeMode { info = fmt.Sprintf("ProxyName [%s], PrivilegeMode is disabled in frps", req.ProxyName) log.Warn("info") return } var ( s *server.ProxyServer ok bool ) s, ok = server.ProxyServers[req.ProxyName] if req.PrivilegeMode && req.Type == consts.NewCtlConn { log.Debug("ProxyName [%s], doLogin and privilege mode is enabled", req.ProxyName) } else { if !ok { info = fmt.Sprintf("ProxyName [%s] is not exist", req.ProxyName) log.Warn(info) return } } // check authKey or privilegeKey nowTime := time.Now().Unix() if req.PrivilegeMode { privilegeKey := pcrypto.GetAuthKey(req.ProxyName + server.PrivilegeToken + fmt.Sprintf("%d", req.Timestamp)) // privilegeKey avaiable in 15 minutes if nowTime-req.Timestamp > 15*60 { info = fmt.Sprintf("ProxyName [%s], privilege mode authorization timeout", req.ProxyName) log.Warn(info) return } else if req.PrivilegeKey != privilegeKey { info = fmt.Sprintf("ProxyName [%s], privilege mode authorization failed", req.ProxyName) log.Warn(info) return } } else { authKey := pcrypto.GetAuthKey(req.ProxyName + s.AuthToken + fmt.Sprintf("%d", req.Timestamp)) // authKey avaiable in 15 minutes if nowTime-req.Timestamp > 15*60 { info = fmt.Sprintf("ProxyName [%s], authorization timeout", req.ProxyName) log.Warn(info) return } else if req.AuthKey != authKey { info = fmt.Sprintf("ProxyName [%s], authorization failed", req.ProxyName) log.Warn(info) return } } // control conn if req.Type == consts.NewCtlConn { if req.PrivilegeMode { s = server.NewProxyServerFromCtlMsg(req) err := server.CreateProxy(s) if err != nil { info = fmt.Sprintf("ProxyName [%s], %v", req.ProxyName, err) log.Warn(info) return } } if s.Status == consts.Working { info = fmt.Sprintf("ProxyName [%s], already in use", req.ProxyName) log.Warn(info) return } // check if vhost_port is set if s.Type == "http" && server.VhostHttpMuxer == nil { info = fmt.Sprintf("ProxyName [%s], type [http] not support when vhost_http_port is not set", req.ProxyName) log.Warn(info) return } if s.Type == "https" && server.VhostHttpsMuxer == nil { info = fmt.Sprintf("ProxyName [%s], type [https] not support when vhost_https_port is not set", req.ProxyName) log.Warn(info) return } // set infomations from frpc s.UseEncryption = req.UseEncryption s.UseGzip = req.UseGzip // start proxy and listen for user connections, no block err := s.Start(c) if err != nil { info = fmt.Sprintf("ProxyName [%s], start proxy error: %v", req.ProxyName, err) log.Warn(info) return } log.Info("ProxyName [%s], start proxy success", req.ProxyName) if req.PrivilegeMode { log.Info("ProxyName [%s], created by PrivilegeMode", req.ProxyName) } } else if req.Type == consts.NewWorkConn { // work conn if s.Status != consts.Working { log.Warn("ProxyName [%s], is not working when it gets one new work connnection", req.ProxyName) return } // the connection will close after join over s.RegisterNewWorkConn(c) } else { info = fmt.Sprintf("Unsupport login message type [%d]", req.Type) log.Warn("Unsupport login message type [%d]", req.Type) return } ret = 0 return }