Stub support for TCP_SYNCNT and TCP_WINDOW_CLAMP.

This change adds support for TCP_SYNCNT and TCP_WINDOW_CLAMP options
in GetSockOpt/SetSockOpt. This change does not really change any
behaviour in Netstack and only stores/returns the stored value.

Actual honoring of these options will be added as required.

Fixes #2626, #2625

PiperOrigin-RevId: 311453777

1 files changed, 39 insertions, 0 deletions

diff --git a/pkg/sentry/socket/netstack/netstack.go b/pkg/sentry/socket/netstack/netstack.go
index 9d032f052..9dea2b5ff 100644
--- a/pkg/sentry/socket/netstack/netstack.go
+++ b/pkg/sentry/socket/netstack/netstack.go
@@ -1321,6 +1321,29 @@ func getSockOptTCP(t *kernel.Task, ep commonEndpoint, name, outLen int) (interfa
 
 		return int32(time.Duration(v) / time.Second), nil
 
+	case linux.TCP_SYNCNT:
+		if outLen < sizeOfInt32 {
+			return nil, syserr.ErrInvalidArgument
+		}
+
+		v, err := ep.GetSockOptInt(tcpip.TCPSynCountOption)
+		if err != nil {
+			return nil, syserr.TranslateNetstackError(err)
+		}
+
+		return int32(v), nil
+
+	case linux.TCP_WINDOW_CLAMP:
+		if outLen < sizeOfInt32 {
+			return nil, syserr.ErrInvalidArgument
+		}
+
+		v, err := ep.GetSockOptInt(tcpip.TCPWindowClampOption)
+		if err != nil {
+			return nil, syserr.TranslateNetstackError(err)
+		}
+
+		return int32(v), nil
 	default:
 		emitUnimplementedEventTCP(t, name)
 	}
@@ -1790,6 +1813,22 @@ func setSockOptTCP(t *kernel.Task, ep commonEndpoint, name int, optVal []byte) *
 		}
 		return syserr.TranslateNetstackError(ep.SetSockOpt(tcpip.TCPDeferAcceptOption(time.Second * time.Duration(v))))
 
+	case linux.TCP_SYNCNT:
+		if len(optVal) < sizeOfInt32 {
+			return syserr.ErrInvalidArgument
+		}
+		v := usermem.ByteOrder.Uint32(optVal)
+
+		return syserr.TranslateNetstackError(ep.SetSockOptInt(tcpip.TCPSynCountOption, int(v)))
+
+	case linux.TCP_WINDOW_CLAMP:
+		if len(optVal) < sizeOfInt32 {
+			return syserr.ErrInvalidArgument
+		}
+		v := usermem.ByteOrder.Uint32(optVal)
+
+		return syserr.TranslateNetstackError(ep.SetSockOptInt(tcpip.TCPWindowClampOption, int(v)))
+
 	case linux.TCP_REPAIR_OPTIONS:
 		t.Kernel().EmitUnimplementedEvent(t)