func (c *Control) reader() { defer func() { if err := recover(); err != nil { c.conn.Warn("Control::reader failed with error %v: %s", err, debug.Stack()) } }() // kill everything if the reader stops defer c.shutdown.Begin() // notify that we're done defer c.readerShutdown.Complete() // read messages from the control channel for { if msg, err := msg.ReadMsg(c.conn); err != nil { if err == io.EOF { c.conn.Info("EOF") return } else { panic(err) } } else { // this can also panic during shutdown c.in <- msg } } }
// Listen for incoming control and proxy connections // We listen for incoming control and proxy connections on the same port // for ease of deployment. The hope is that by running on port 443, using // TLS and running all connections over the same port, we can bust through // restrictive firewalls. func tunnelListener(addr string, tlsConfig *tls.Config) { // listen for incoming connections listener, err := conn.Listen(addr, "tun", tlsConfig) if err != nil { panic(err) } log.Info("Listening for control and proxy connections on %s", listener.Addr.String()) for c := range listener.Conns { go func(tunnelConn conn.Conn) { tunnelConn.SetReadDeadline(time.Now().Add(connReadTimeout)) var rawMsg msg.Message if rawMsg, err = msg.ReadMsg(tunnelConn); err != nil { tunnelConn.Error("Failed to read message: %v", err) tunnelConn.Close() return } // don't timeout after the initial read, tunnel heartbeating will kill // dead connections tunnelConn.SetReadDeadline(time.Time{}) switch m := rawMsg.(type) { case *msg.Auth: NewControl(tunnelConn, m) case *msg.RegProxy: NewProxy(tunnelConn, m) default: tunnelConn.Close() } }(c) } }
// Listen for incoming control and proxy connections // We listen for incoming control and proxy connections on the same port // for ease of deployment. The hope is that by running on port 443, using // TLS and running all connections over the same port, we can bust through // restrictive firewalls. func tunnelListener(addr string, tlsConfig *tls.Config, secret string) { // listen for incoming connections listener, err := conn.Listen(addr, "tun", tlsConfig) if err != nil { panic(err) } log.Info("Listening for control and proxy connections on %s", listener.Addr.String()) if secret != "" { log.Info("Clients should use '%s' as secret", secret) } for c := range listener.Conns { go func(tunnelConn conn.Conn) { // don't crash on panics defer func() { if r := recover(); r != nil { tunnelConn.Info("tunnelListener failed with error %v: %s", r, debug.Stack()) } }() tunnelConn.SetReadDeadline(time.Now().Add(connReadTimeout)) var rawMsg msg.Message if rawMsg, err = msg.ReadMsg(tunnelConn); err != nil { tunnelConn.Warn("Failed to read message: %v", err) tunnelConn.Close() return } // don't timeout after the initial read, tunnel heartbeating will kill // dead connections tunnelConn.SetReadDeadline(time.Time{}) switch m := rawMsg.(type) { case *msg.Auth: NewControl(tunnelConn, m, secret) case *msg.RegProxy: NewProxy(tunnelConn, m) default: tunnelConn.Close() } }(c) } }
func (c *Control) readThread() { defer func() { if err := recover(); err != nil { c.conn.Info("Control::readThread failed with error %v: %s", err, debug.Stack()) } c.stop <- nil }() // read messages from the control channel for { if msg, err := msg.ReadMsg(c.conn); err != nil { if err == io.EOF { c.conn.Info("EOF") return } else { panic(err) } } else { c.in <- msg } } }
// Establishes and manages a tunnel control connection with the server func (c *ClientModel) control() { defer func() { if r := recover(); r != nil { log.Error("control recovering from failure %v", r) } }() // establish control channel var ( ctlConn conn.Conn err error ) if c.proxyUrl == "" { // simple non-proxied case, just connect to the server ctlConn, err = conn.Dial(c.serverAddr, "ctl", c.tlsConfig) } else { ctlConn, err = conn.DialHttpProxy(c.proxyUrl, c.serverAddr, "ctl", c.tlsConfig) } if err != nil { panic(err) } defer ctlConn.Close() // authenticate with the server auth := &msg.Auth{ ClientId: c.id, OS: runtime.GOOS, Arch: runtime.GOARCH, Version: version.Proto, MmVersion: version.MajorMinor(), User: c.authToken, } if err = msg.WriteMsg(ctlConn, auth); err != nil { panic(err) } // wait for the server to authenticate us var authResp msg.AuthResp if err = msg.ReadMsgInto(ctlConn, &authResp); err != nil { panic(err) } if authResp.Error != "" { emsg := fmt.Sprintf("Failed to authenticate to server: %s", authResp.Error) c.ctl.Shutdown(emsg) return } c.id = authResp.ClientId c.serverVersion = authResp.MmVersion c.Info("Authenticated with server, client id: %v", c.id) c.update() if err = SaveAuthToken(c.configPath, c.authToken); err != nil { c.Error("Failed to save auth token: %v", err) } // request tunnels reqIdToTunnelConfig := make(map[string]*TunnelConfiguration) for _, config := range c.tunnelConfig { // create the protocol list to ask for var protocols []string for proto, _ := range config.Protocols { protocols = append(protocols, proto) } reqTunnel := &msg.ReqTunnel{ ReqId: util.RandId(8), Protocol: strings.Join(protocols, "+"), Hostname: config.Hostname, Subdomain: config.Subdomain, HttpAuth: config.HttpAuth, RemotePort: config.RemotePort, } // send the tunnel request if err = msg.WriteMsg(ctlConn, reqTunnel); err != nil { panic(err) } // save request id association so we know which local address // to proxy to later reqIdToTunnelConfig[reqTunnel.ReqId] = config } // start the heartbeat lastPong := time.Now().UnixNano() c.ctl.Go(func() { c.heartbeat(&lastPong, ctlConn) }) // main control loop for { var rawMsg msg.Message if rawMsg, err = msg.ReadMsg(ctlConn); err != nil { panic(err) } switch m := rawMsg.(type) { case *msg.ReqProxy: c.ctl.Go(c.proxy) case *msg.Pong: atomic.StoreInt64(&lastPong, time.Now().UnixNano()) case *msg.NewTunnel: if m.Error != "" { emsg := fmt.Sprintf("Server failed to allocate tunnel: %s", m.Error) c.Error(emsg) c.ctl.Shutdown(emsg) continue } tunnel := mvc.Tunnel{ PublicUrl: m.Url, LocalAddr: reqIdToTunnelConfig[m.ReqId].Protocols[m.Protocol], Protocol: c.protoMap[m.Protocol], } c.tunnels[tunnel.PublicUrl] = tunnel c.connStatus = mvc.ConnOnline c.Info("Tunnel established at %v", tunnel.PublicUrl) c.update() default: ctlConn.Warn("Ignoring unknown control message %v ", m) } } }
/** * Establishes and manages a tunnel control connection with the server */ func control(s *State, ctl *ui.Controller) { defer func() { if r := recover(); r != nil { log.Error("control recovering from failure %v", r) } }() // establish control channel conn, err := conn.Dial(s.opts.server, "ctl", tlsConfig) if err != nil { panic(err) } defer conn.Close() // register with the server err = msg.WriteMsg(conn, &msg.RegMsg{ Protocol: s.opts.protocol, OS: runtime.GOOS, HttpAuth: s.opts.httpAuth, Hostname: s.opts.hostname, Subdomain: s.opts.subdomain, ClientId: s.id, Version: version.Proto, MmVersion: version.MajorMinor(), User: s.opts.authtoken, }) if err != nil { panic(err) } // wait for the server to ack our register var regAck msg.RegAckMsg if err = msg.ReadMsgInto(conn, ®Ack); err != nil { panic(err) } if regAck.Error != "" { emsg := fmt.Sprintf("Server failed to allocate tunnel: %s", regAck.Error) ctl.Cmds <- ui.CmdQuit{Message: emsg} return } // update UI state s.publicUrl = regAck.Url conn.Info("Tunnel established at %v", s.GetPublicUrl()) s.status = "online" s.serverVersion = regAck.MmVersion ctl.Update(s) SaveAuthToken(s.opts.authtoken) // start the heartbeat lastPong := time.Now().UnixNano() go heartbeat(&lastPong, conn) // main control loop for { var m msg.Message if m, err = msg.ReadMsg(conn); err != nil { panic(err) } switch m.(type) { case *msg.ReqProxyMsg: go proxy(regAck.ProxyAddr, s, ctl) case *msg.PongMsg: atomic.StoreInt64(&lastPong, time.Now().UnixNano()) } } }