func (m *TermMonitor) termOnStdinClose() { _, err := io.Copy(ioutil.Discard, os.Stdin) // io.Copy() will return a nil on EOF, since reaching EOF is // expected behavior. No matter what, if this unblocks, assume // that stdin is closed, and treat that as having received a // SIGTERM. log.Noticef("Stdin is closed or unreadable: %v", err) m.sigChan <- syscall.SIGTERM }
func (m *TermMonitor) termOnPPIDChange(ppid int) { // Under most if not all U*IX systems, the parent PID will change // to that of init once the parent dies. There are several notable // exceptions (Slowlaris/Android), but the parent PID changes // under those platforms as well. // // Naturally we lose if the parent has died by the time when the // Getppid() call was issued in our parent, but, this is better // than nothing. const ppidPollInterval = 1 * time.Second for ppid == os.Getppid() { time.Sleep(ppidPollInterval) } // Treat the parent PID changing as the same as having received // a SIGTERM. log.Noticef("Parent pid changed: %d (was %d)", os.Getppid(), ppid) m.sigChan <- syscall.SIGTERM }
func main() { // Initialize the termination state monitor as soon as possible. termMon = termmon.NewTermMonitor() // Handle the command line arguments. _, execName := path.Split(os.Args[0]) showVer := flag.Bool("version", false, "Print version and exit") logLevelStr := flag.String("logLevel", "ERROR", "Log level (ERROR/WARN/INFO/DEBUG)") enableLogging := flag.Bool("enableLogging", false, "Log to TOR_PT_STATE_LOCATION/"+obfs4proxyLogFile) unsafeLogging := flag.Bool("unsafeLogging", false, "Disable the address scrubber") transparent := flag.Bool("transparent", false, "Enable transparent proxy mode") udp := flag.Bool("udp", false, "Enable UDP proxy mode") target := flag.String("target", "", "Specify transport server destination address") clientMode := flag.Bool("client", false, "Enable client mode") serverMode := flag.Bool("server", false, "Enable server mode") statePath := flag.String("state", "", "Specify transport server destination address") bindAddr := flag.String("bindaddr", "", "Specify the bind address for transparent server") flag.Parse() if *showVer { fmt.Printf("%s\n", getVersion()) os.Exit(0) } if err := log.SetLogLevel(*logLevelStr); err != nil { fmt.Println("failed to set log level") golog.Fatalf("[ERROR]: %s - failed to set log level: %s", execName, err) } // Determine if this is a client or server, initialize the common state. var ptListeners []net.Listener launched := false isClient, err := checkIsClient(*clientMode, *serverMode) if err != nil { golog.Fatalf("[ERROR]: %s - must be run as a managed transport", execName) } if stateDir, err = makeStateDir(*statePath); err != nil { golog.Fatalf("[ERROR]: %s - No state directory: %s", execName, err) } if err = log.Init(*enableLogging, path.Join(stateDir, obfs4proxyLogFile), *unsafeLogging); err != nil { golog.Fatalf("[ERROR]: %s - failed to initialize logging", execName) } if err = transports.Init(); err != nil { log.Errorf("%s - failed to initialize transports: %s", execName, err) os.Exit(-1) } log.Noticef("%s - launched", getVersion()) fmt.Println("launching") if *transparent { // Do the transparent proxy configuration. log.Infof("%s - initializing transparent proxy", execName) if *udp { log.Infof("%s - initializing UDP transparent proxy", execName) if isClient { log.Infof("%s - initializing client transport listeners", execName) if *target == "" { log.Errorf("%s - transparent mode requires a target", execName) } else { fmt.Println("transparent udp client") launched = transparent_udp.ClientSetup(termMon, *target) } } else { log.Infof("%s - initializing server transport listeners", execName) if *bindAddr == "" { fmt.Println("%s - transparent mode requires a bindaddr", execName) } else { fmt.Println("transparent udp server") launched = transparent_udp.ServerSetup(termMon, *bindAddr, *target) fmt.Println("launched", launched, ptListeners) } } } else { log.Infof("%s - initializing TCP transparent proxy", execName) if isClient { log.Infof("%s - initializing client transport listeners", execName) if *target == "" { log.Errorf("%s - transparent mode requires a target", execName) } else { launched, ptListeners = transparent_tcp.ClientSetup(termMon, *target) } } else { log.Infof("%s - initializing server transport listeners", execName) if *bindAddr == "" { fmt.Println("%s - transparent mode requires a bindaddr", execName) } else { launched, ptListeners = transparent_tcp.ServerSetup(termMon, *bindAddr) fmt.Println("launched", launched, ptListeners) } } } } else { if *udp { log.Infof("%s - initializing STUN UDP proxy", execName) if isClient { log.Infof("%s - initializing client transport listeners", execName) if *target == "" { log.Errorf("%s - STUN mode requires a target", execName) } else { fmt.Println("STUN udp client") launched = stun_udp.ClientSetup(termMon, *target) } } else { log.Infof("%s - initializing server transport listeners", execName) if *bindAddr == "" { fmt.Println("%s - STUN mode requires a bindaddr", execName) } else { fmt.Println("STUN udp server") launched = stun_udp.ServerSetup(termMon, *bindAddr, *target) fmt.Println("launched", launched, ptListeners) } } } else { // Do the managed pluggable transport protocol configuration. log.Infof("%s - initializing PT 1.0 proxy", execName) if isClient { log.Infof("%s - initializing client transport listeners", execName) launched, ptListeners = pt_socks5.ClientSetup(termMon) } else { log.Infof("%s - initializing server transport listeners", execName) launched, ptListeners = pt_socks5.ServerSetup(termMon) } } } if !launched { // Initialization failed, the client or server setup routines should // have logged, so just exit here. os.Exit(-1) } fmt.Println("launched") log.Infof("%s - accepting connections", execName) defer func() { log.Noticef("%s - terminated", execName) }() // At this point, the pt config protocol is finished, and incoming // connections will be processed. Wait till the parent dies // (immediate exit), a SIGTERM is received (immediate exit), // or a SIGINT is received. if sig := termMon.Wait(false); sig == syscall.SIGTERM { return } // Ok, it was the first SIGINT, close all listeners, and wait till, // the parent dies, all the current connections are closed, or either // a SIGINT/SIGTERM is received, and exit. for _, ln := range ptListeners { ln.Close() } termMon.Wait(true) fmt.Println("waiting") for { // FIXME - block because termMon.Wait is not blocking } }