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 = 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")
flag.Parse()
if *showVer {
fmt.Printf("%s\n", getVersion())
os.Exit(0)
}
if err := log.SetLogLevel(*logLevelStr); err != nil {
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 := ptIsClient()
if err != nil {
golog.Fatalf("[ERROR]: %s - must be run as a managed transport", execName)
}
if stateDir, err = pt.MakeStateDir(); 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())
// Do the managed pluggable transport protocol configuration.
if isClient {
log.Infof("%s - initializing client transport listeners", execName)
launched, ptListeners = clientSetup()
} else {
log.Infof("%s - initializing server transport listeners", execName)
launched, ptListeners = serverSetup()
}
if !launched {
// Initialization failed, the client or server setup routines should
// have logged, so just exit here.
os.Exit(-1)
}
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)
}