[netstack] Move SO_KEEPALIVE and SO_ACCEPTCONN option to SocketOptions.

PiperOrigin-RevId: 343217712

9 files changed, 56 insertions, 60 deletions

diff --git a/pkg/tcpip/socketops.go b/pkg/tcpip/socketops.go
index 99c3e9c45..1b1188ee5 100644
--- a/pkg/tcpip/socketops.go
+++ b/pkg/tcpip/socketops.go
@@ -19,14 +19,23 @@ import (
 )
 
 // SocketOptionsHandler holds methods that help define endpoint specific
-// behavior for socket options. These must be implemented by endpoints to get
-// notified when socket level options are set.
+// behavior for socket options.
+// These must be implemented by endpoints to:
+// - Get notified when socket level options are set.
+// - Provide endpoint specific socket options.
 type SocketOptionsHandler interface {
 	// OnReuseAddressSet is invoked when SO_REUSEADDR is set for an endpoint.
 	OnReuseAddressSet(v bool)
 
 	// OnReusePortSet is invoked when SO_REUSEPORT is set for an endpoint.
 	OnReusePortSet(v bool)
+
+	// OnKeepAliveSet is invoked when SO_KEEPALIVE is set for an endpoint.
+	OnKeepAliveSet(v bool)
+
+	// IsListening is invoked to fetch SO_ACCEPTCONN option value for an
+	// endpoint. It is used to indicate if the socket is a listening socket.
+	IsListening() bool
 }
 
 // DefaultSocketOptionsHandler is an embeddable type that implements no-op
@@ -41,6 +50,12 @@ func (*DefaultSocketOptionsHandler) OnReuseAddressSet(bool) {}
 // OnReusePortSet implements SocketOptionsHandler.OnReusePortSet.
 func (*DefaultSocketOptionsHandler) OnReusePortSet(bool) {}
 
+// OnKeepAliveSet implements SocketOptionsHandler.OnKeepAliveSet.
+func (*DefaultSocketOptionsHandler) OnKeepAliveSet(bool) {}
+
+// IsListening implements SocketOptionsHandler.IsListening.
+func (*DefaultSocketOptionsHandler) IsListening() bool { return false }
+
 // SocketOptions contains all the variables which store values for SOL_SOCKET
 // level options.
 //
@@ -69,6 +84,10 @@ type SocketOptions struct {
 	// reusePortEnabled determines whether to permit multiple sockets to be bound
 	// to an identical socket address.
 	reusePortEnabled uint32
+
+	// keepAliveEnabled determines whether TCP keepalive is enabled for this
+	// socket.
+	keepAliveEnabled uint32
 }
 
 // InitHandler initializes the handler. This must be called before using the
@@ -136,3 +155,20 @@ func (so *SocketOptions) SetReusePort(v bool) {
 	storeAtomicBool(&so.reusePortEnabled, v)
 	so.handler.OnReusePortSet(v)
 }
+
+// GetKeepAlive gets value for SO_KEEPALIVE option.
+func (so *SocketOptions) GetKeepAlive() bool {
+	return atomic.LoadUint32(&so.keepAliveEnabled) != 0
+}
+
+// SetKeepAlive sets value for SO_KEEPALIVE option.
+func (so *SocketOptions) SetKeepAlive(v bool) {
+	storeAtomicBool(&so.keepAliveEnabled, v)
+	so.handler.OnKeepAliveSet(v)
+}
+
+// GetAcceptConn gets value for SO_ACCEPTCONN option.
+func (so *SocketOptions) GetAcceptConn() bool {
+	// This option is completely endpoint dependent and unsettable.
+	return so.handler.IsListening()
+}
diff --git a/pkg/tcpip/tcpip.go b/pkg/tcpip/tcpip.go
index 7ae36fde7..4c367b6a6 100644
--- a/pkg/tcpip/tcpip.go
+++ b/pkg/tcpip/tcpip.go
@@ -708,10 +708,6 @@ const (
 	// TCP, it determines if the Nagle algorithm is on or off.
 	DelayOption
 
-	// KeepaliveEnabledOption is used by SetSockOptBool/GetSockOptBool to
-	// specify whether TCP keepalive is enabled for this socket.
-	KeepaliveEnabledOption
-
 	// MulticastLoopOption is used by SetSockOptBool/GetSockOptBool to
 	// specify whether multicast packets sent over a non-loopback interface
 	// will be looped back.
@@ -747,10 +743,6 @@ const (
 	// endpoint that all packets being written have an IP header and the
 	// endpoint should not attach an IP header.
 	IPHdrIncludedOption
-
-	// AcceptConnOption is used by GetSockOptBool to indicate if the
-	// socket is a listening socket.
-	AcceptConnOption
 )
 
 // SockOptInt represents socket options which values have the int type.
diff --git a/pkg/tcpip/transport/icmp/endpoint.go b/pkg/tcpip/transport/icmp/endpoint.go
index 39560a9fa..59ec54ca0 100644
--- a/pkg/tcpip/transport/icmp/endpoint.go
+++ b/pkg/tcpip/transport/icmp/endpoint.go
@@ -383,13 +383,7 @@ func (e *endpoint) SetSockOptInt(opt tcpip.SockOptInt, v int) *tcpip.Error {
 
 // GetSockOptBool implements tcpip.Endpoint.GetSockOptBool.
 func (e *endpoint) GetSockOptBool(opt tcpip.SockOptBool) (bool, *tcpip.Error) {
-	switch opt {
-	case tcpip.KeepaliveEnabledOption, tcpip.AcceptConnOption:
-		return false, nil
-
-	default:
-		return false, tcpip.ErrUnknownProtocolOption
-	}
+	return false, tcpip.ErrUnknownProtocolOption
 }
 
 // GetSockOptInt implements tcpip.Endpoint.GetSockOptInt.
diff --git a/pkg/tcpip/transport/packet/endpoint.go b/pkg/tcpip/transport/packet/endpoint.go
index 35d1be792..e2c7a0d62 100644
--- a/pkg/tcpip/transport/packet/endpoint.go
+++ b/pkg/tcpip/transport/packet/endpoint.go
@@ -395,12 +395,7 @@ func (ep *endpoint) GetSockOpt(opt tcpip.GettableSocketOption) *tcpip.Error {
 
 // GetSockOptBool implements tcpip.Endpoint.GetSockOptBool.
 func (*endpoint) GetSockOptBool(opt tcpip.SockOptBool) (bool, *tcpip.Error) {
-	switch opt {
-	case tcpip.AcceptConnOption:
-		return false, nil
-	default:
-		return false, tcpip.ErrNotSupported
-	}
+	return false, tcpip.ErrNotSupported
 }
 
 // GetSockOptInt implements tcpip.Endpoint.GetSockOptInt.
diff --git a/pkg/tcpip/transport/raw/endpoint.go b/pkg/tcpip/transport/raw/endpoint.go
index e64392f7b..b0b53b181 100644
--- a/pkg/tcpip/transport/raw/endpoint.go
+++ b/pkg/tcpip/transport/raw/endpoint.go
@@ -607,9 +607,6 @@ func (e *endpoint) GetSockOpt(opt tcpip.GettableSocketOption) *tcpip.Error {
 // GetSockOptBool implements tcpip.Endpoint.GetSockOptBool.
 func (e *endpoint) GetSockOptBool(opt tcpip.SockOptBool) (bool, *tcpip.Error) {
 	switch opt {
-	case tcpip.KeepaliveEnabledOption, tcpip.AcceptConnOption:
-		return false, nil
-
 	case tcpip.IPHdrIncludedOption:
 		e.mu.Lock()
 		v := e.hdrIncluded
diff --git a/pkg/tcpip/transport/tcp/connect.go b/pkg/tcpip/transport/tcp/connect.go
index 6661e8915..88a632019 100644
--- a/pkg/tcpip/transport/tcp/connect.go
+++ b/pkg/tcpip/transport/tcp/connect.go
@@ -1284,7 +1284,7 @@ func (e *endpoint) keepaliveTimerExpired() *tcpip.Error {
 	userTimeout := e.userTimeout
 
 	e.keepalive.Lock()
-	if !e.keepalive.enabled || !e.keepalive.timer.checkExpiration() {
+	if !e.SocketOptions().GetKeepAlive() || !e.keepalive.timer.checkExpiration() {
 		e.keepalive.Unlock()
 		return nil
 	}
@@ -1321,7 +1321,7 @@ func (e *endpoint) resetKeepaliveTimer(receivedData bool) {
 	}
 	// Start the keepalive timer IFF it's enabled and there is no pending
 	// data to send.
-	if !e.keepalive.enabled || e.snd == nil || e.snd.sndUna != e.snd.sndNxt {
+	if !e.SocketOptions().GetKeepAlive() || e.snd == nil || e.snd.sndUna != e.snd.sndNxt {
 		e.keepalive.timer.disable()
 		e.keepalive.Unlock()
 		return
diff --git a/pkg/tcpip/transport/tcp/endpoint.go b/pkg/tcpip/transport/tcp/endpoint.go
index f893324c2..9c9f1ab87 100644
--- a/pkg/tcpip/transport/tcp/endpoint.go
+++ b/pkg/tcpip/transport/tcp/endpoint.go
@@ -851,7 +851,6 @@ func (e *endpoint) recentTimestamp() uint32 {
 // +stateify savable
 type keepalive struct {
 	sync.Mutex `state:"nosave"`
-	enabled    bool
 	idle       time.Duration
 	interval   time.Duration
 	count      int
@@ -1643,6 +1642,11 @@ func (e *endpoint) OnReusePortSet(v bool) {
 	e.UnlockUser()
 }
 
+// OnKeepAliveSet implements tcpip.SocketOptionsHandler.OnKeepAliveSet.
+func (e *endpoint) OnKeepAliveSet(v bool) {
+	e.notifyProtocolGoroutine(notifyKeepaliveChanged)
+}
+
 // SetSockOptBool sets a socket option.
 func (e *endpoint) SetSockOptBool(opt tcpip.SockOptBool, v bool) *tcpip.Error {
 	switch opt {
@@ -1669,12 +1673,6 @@ func (e *endpoint) SetSockOptBool(opt tcpip.SockOptBool, v bool) *tcpip.Error {
 			e.sndWaker.Assert()
 		}
 
-	case tcpip.KeepaliveEnabledOption:
-		e.keepalive.Lock()
-		e.keepalive.enabled = v
-		e.keepalive.Unlock()
-		e.notifyProtocolGoroutine(notifyKeepaliveChanged)
-
 	case tcpip.QuickAckOption:
 		o := uint32(1)
 		if v {
@@ -1980,6 +1978,13 @@ func (e *endpoint) readyReceiveSize() (int, *tcpip.Error) {
 	return e.rcvBufUsed, nil
 }
 
+// IsListening implements tcpip.SocketOptionsHandler.IsListening.
+func (e *endpoint) IsListening() bool {
+	e.LockUser()
+	defer e.UnlockUser()
+	return e.EndpointState() == StateListen
+}
+
 // GetSockOptBool implements tcpip.Endpoint.GetSockOptBool.
 func (e *endpoint) GetSockOptBool(opt tcpip.SockOptBool) (bool, *tcpip.Error) {
 	switch opt {
@@ -1990,13 +1995,6 @@ func (e *endpoint) GetSockOptBool(opt tcpip.SockOptBool) (bool, *tcpip.Error) {
 	case tcpip.DelayOption:
 		return atomic.LoadUint32(&e.delay) != 0, nil
 
-	case tcpip.KeepaliveEnabledOption:
-		e.keepalive.Lock()
-		v := e.keepalive.enabled
-		e.keepalive.Unlock()
-
-		return v, nil
-
 	case tcpip.QuickAckOption:
 		v := atomic.LoadUint32(&e.slowAck) == 0
 		return v, nil
@@ -2016,12 +2014,6 @@ func (e *endpoint) GetSockOptBool(opt tcpip.SockOptBool) (bool, *tcpip.Error) {
 	case tcpip.MulticastLoopOption:
 		return true, nil
 
-	case tcpip.AcceptConnOption:
-		e.LockUser()
-		defer e.UnlockUser()
-
-		return e.EndpointState() == StateListen, nil
-
 	default:
 		return false, tcpip.ErrUnknownProtocolOption
 	}
diff --git a/pkg/tcpip/transport/tcp/tcp_test.go b/pkg/tcpip/transport/tcp/tcp_test.go
index 9fa3aa740..7124a715d 100644
--- a/pkg/tcpip/transport/tcp/tcp_test.go
+++ b/pkg/tcpip/transport/tcp/tcp_test.go
@@ -4984,9 +4984,7 @@ func TestKeepalive(t *testing.T) {
 	if err := c.EP.SetSockOptInt(tcpip.KeepaliveCountOption, 5); err != nil {
 		t.Fatalf("c.EP.SetSockOptInt(tcpip.KeepaliveCountOption, 5): %s", err)
 	}
-	if err := c.EP.SetSockOptBool(tcpip.KeepaliveEnabledOption, true); err != nil {
-		t.Fatalf("c.EP.SetSockOptBool(tcpip.KeepaliveEnabledOption, true): %s", err)
-	}
+	c.EP.SocketOptions().SetKeepAlive(true)
 
 	// 5 unacked keepalives are sent. ACK each one, and check that the
 	// connection stays alive after 5.
@@ -7236,9 +7234,7 @@ func TestKeepaliveWithUserTimeout(t *testing.T) {
 	if err := c.EP.SetSockOptInt(tcpip.KeepaliveCountOption, 10); err != nil {
 		t.Fatalf("c.EP.SetSockOptInt(tcpip.KeepaliveCountOption, 10): %s", err)
 	}
-	if err := c.EP.SetSockOptBool(tcpip.KeepaliveEnabledOption, true); err != nil {
-		t.Fatalf("c.EP.SetSockOptBool(tcpip.KeepaliveEnabledOption, true): %s", err)
-	}
+	c.EP.SocketOptions().SetKeepAlive(true)
 
 	// Set userTimeout to be the duration to be 1 keepalive
 	// probes. Which means that after the first probe is sent
diff --git a/pkg/tcpip/transport/udp/endpoint.go b/pkg/tcpip/transport/udp/endpoint.go
index e57833644..a7a405dcb 100644
--- a/pkg/tcpip/transport/udp/endpoint.go
+++ b/pkg/tcpip/transport/udp/endpoint.go
@@ -849,9 +849,6 @@ func (e *endpoint) SetSockOpt(opt tcpip.SettableSocketOption) *tcpip.Error {
 // GetSockOptBool implements tcpip.Endpoint.GetSockOptBool.
 func (e *endpoint) GetSockOptBool(opt tcpip.SockOptBool) (bool, *tcpip.Error) {
 	switch opt {
-	case tcpip.KeepaliveEnabledOption:
-		return false, nil
-
 	case tcpip.MulticastLoopOption:
 		e.mu.RLock()
 		v := e.multicastLoop
@@ -893,9 +890,6 @@ func (e *endpoint) GetSockOptBool(opt tcpip.SockOptBool) (bool, *tcpip.Error) {
 
 		return v, nil
 
-	case tcpip.AcceptConnOption:
-		return false, nil
-
 	default:
 		return false, tcpip.ErrUnknownProtocolOption
 	}