if err != nil {
return err
}
+ go func() {
+ err := srv.Wait()
+ gw.Log.Printf("gateway server stopped: %s", err)
+ }()
// Get the port number we are listening on (extPort might be
// "0" or a port name, in which case this will be different).
_, listenPort, err := net.SplitHostPort(srv.Addr)
// non-tunnel connections aren't available; and PORT is the
// port number we are listening on.
gw.Address = net.JoinHostPort(extHost, listenPort)
+ gw.Log.Printf("gateway server listening at %s", gw.Address)
if gw.ArvadosClient != nil {
go gw.maintainTunnel(gw.Address)
}
gw.UpdateTunnelURL(url)
}
for {
- muxconn, err := mux.Accept()
+ muxconn, err := mux.AcceptStream()
if err != nil {
return err
}
- gw.Log.Printf("receiving connection from tunnel, remoteAddr %s", muxconn.RemoteAddr().String())
+ gw.Log.Printf("tunnel connection %d started", muxconn.StreamID())
go func() {
defer muxconn.Close()
gwconn, err := net.Dial("tcp", addr)
if err != nil {
- gw.Log.Printf("error connecting to %s on behalf of tunnel connection: %s", addr, err)
+ gw.Log.Printf("tunnel connection %d: error connecting to %s: %s", muxconn.StreamID(), addr, err)
return
}
defer gwconn.Close()
wg.Add(2)
go func() {
defer wg.Done()
- io.Copy(gwconn, muxconn)
+ _, err := io.Copy(gwconn, muxconn)
+ if err != nil {
+ gw.Log.Printf("tunnel connection %d: mux end: %s", muxconn.StreamID(), err)
+ }
+ gwconn.Close()
}()
go func() {
defer wg.Done()
- io.Copy(muxconn, gwconn)
+ _, err := io.Copy(muxconn, gwconn)
+ if err != nil {
+ gw.Log.Printf("tunnel connection %d: gateway end: %s", muxconn.StreamID(), err)
+ }
+ muxconn.Close()
}()
wg.Wait()
+ gw.Log.Printf("tunnel connection %d finished", muxconn.StreamID())
}()
}
}
func (gw *Gateway) handleSession(ctx context.Context, newch ssh.NewChannel, detachKeys, username string) {
ch, reqs, err := newch.Accept()
if err != nil {
- gw.Log.Printf("accept session channel: %s", err)
+ gw.Log.Printf("error accepting session channel: %s", err)
return
}
+ defer ch.Close()
+
var pty0, tty0 *os.File
// Where to send errors/messages for the client to see
logw := io.Writer(ch.Stderr())
eol := "\n"
// Env vars to add to child process
termEnv := []string(nil)
- for req := range reqs {
+
+ started := 0
+ wantClose := make(chan struct{})
+ for {
+ var req *ssh.Request
+ select {
+ case r, ok := <-reqs:
+ if !ok {
+ return
+ }
+ req = r
+ case <-wantClose:
+ return
+ }
ok := false
switch req.Type {
case "shell", "exec":
+ if started++; started != 1 {
+ // RFC 4254 6.5: "Only one of these
+ // requests can succeed per channel."
+ break
+ }
ok = true
var payload struct {
Command string
}
defer func() {
ch.SendRequest("exit-status", false, ssh.Marshal(&resp))
- ch.Close()
+ close(wantClose)
}()
cmd, err := gw.Target.InjectCommand(ctx, detachKeys, username, tty0 != nil, execargs)
resp.Status = 1
return
}
- cmd.Stdin = ch
- cmd.Stdout = ch
- cmd.Stderr = ch.Stderr()
if tty0 != nil {
cmd.Stdin = tty0
cmd.Stdout = tty0
cmd.Stderr = tty0
- var wg sync.WaitGroup
- defer wg.Wait()
- wg.Add(2)
- go func() { io.Copy(ch, pty0); wg.Done() }()
- go func() { io.Copy(pty0, ch); wg.Done() }()
+ go io.Copy(ch, pty0)
+ go io.Copy(pty0, ch)
// Send our own debug messages to tty as well.
logw = tty0
+ } else {
+ // StdinPipe may seem
+ // superfluous here, but it's
+ // not: it causes cmd.Run() to
+ // return when the subprocess
+ // exits. Without it, Run()
+ // waits for stdin to close,
+ // which causes "ssh ... echo
+ // ok" (with the client's
+ // stdin connected to a
+ // terminal or something) to
+ // hang.
+ stdin, err := cmd.StdinPipe()
+ if err != nil {
+ fmt.Fprintln(ch.Stderr(), err)
+ ch.CloseWrite()
+ resp.Status = 1
+ return
+ }
+ go func() {
+ io.Copy(stdin, ch)
+ stdin.Close()
+ }()
+ cmd.Stdout = ch
+ cmd.Stderr = ch.Stderr()
}
cmd.SysProcAttr = &syscall.SysProcAttr{
Setctty: tty0 != nil,
// would be a gaping security
// hole).
default:
- // fmt.Fprintf(logw, "declining %q req"+eol, req.Type)
+ // fmt.Fprintf(logw, "declined request %q on ssh channel"+eol, req.Type)
}
if req.WantReply {
req.Reply(ok, nil)