From 3e73c519a55191827dcc6e98ea0ffe977acbb73f Mon Sep 17 00:00:00 2001
From: Ayush Ranjan <ayushranjan@google.com>
Date: Wed, 18 Nov 2020 13:40:23 -0800
Subject: [PATCH] [netstack] Move SO_NO_CHECK option to SocketOptions.

PiperOrigin-RevId: 343146856
---
 pkg/sentry/socket/netstack/netstack.go | 11 ++++-------
 pkg/tcpip/socketops.go                 | 14 ++++++++++++++
 pkg/tcpip/transport/udp/endpoint.go    | 14 +-------------
 pkg/tcpip/transport/udp/udp_test.go    |  8 ++------
 test/syscalls/linux/socket_generic.cc  |  2 +-
 5 files changed, 22 insertions(+), 27 deletions(-)

diff --git a/pkg/sentry/socket/netstack/netstack.go b/pkg/sentry/socket/netstack/netstack.go
index 9c927efa0..d48b92c66 100644
--- a/pkg/sentry/socket/netstack/netstack.go
+++ b/pkg/sentry/socket/netstack/netstack.go
@@ -1232,12 +1232,8 @@ func getSockOptSocket(t *kernel.Task, s socket.SocketOps, ep commonEndpoint, fam
 			return nil, syserr.ErrInvalidArgument
 		}
 
-		v, err := ep.GetSockOptBool(tcpip.NoChecksumOption)
-		if err != nil {
-			return nil, syserr.TranslateNetstackError(err)
-		}
-		vP := primitive.Int32(boolToInt32(v))
-		return &vP, nil
+		v := primitive.Int32(boolToInt32(ep.SocketOptions().GetNoChecksum()))
+		return &v, nil
 
 	case linux.SO_ACCEPTCONN:
 		if outLen < sizeOfInt32 {
@@ -1977,7 +1973,8 @@ func setSockOptSocket(t *kernel.Task, s socket.SocketOps, ep commonEndpoint, nam
 		}
 
 		v := usermem.ByteOrder.Uint32(optVal)
-		return syserr.TranslateNetstackError(ep.SetSockOptBool(tcpip.NoChecksumOption, v != 0))
+		ep.SocketOptions().SetNoChecksum(v != 0)
+		return nil
 
 	case linux.SO_LINGER:
 		if len(optVal) < linux.SizeOfLinger {
diff --git a/pkg/tcpip/socketops.go b/pkg/tcpip/socketops.go
index e1b0d6354..cc3d59d9d 100644
--- a/pkg/tcpip/socketops.go
+++ b/pkg/tcpip/socketops.go
@@ -32,6 +32,10 @@ type SocketOptions struct {
 	// passCredEnabled determines whether SCM_CREDENTIALS socket control messages
 	// are enabled.
 	passCredEnabled uint32
+
+	// noChecksumEnabled determines whether UDP checksum is disabled while
+	// transmitting for this socket.
+	noChecksumEnabled uint32
 }
 
 func storeAtomicBool(addr *uint32, v bool) {
@@ -61,3 +65,13 @@ func (so *SocketOptions) GetPassCred() bool {
 func (so *SocketOptions) SetPassCred(v bool) {
 	storeAtomicBool(&so.passCredEnabled, v)
 }
+
+// GetNoChecksum gets value for SO_NO_CHECK option.
+func (so *SocketOptions) GetNoChecksum() bool {
+	return atomic.LoadUint32(&so.noChecksumEnabled) != 0
+}
+
+// SetNoChecksum sets value for SO_NO_CHECK option.
+func (so *SocketOptions) SetNoChecksum(v bool) {
+	storeAtomicBool(&so.noChecksumEnabled, v)
+}
diff --git a/pkg/tcpip/transport/udp/endpoint.go b/pkg/tcpip/transport/udp/endpoint.go
index 648587137..5aa16bf35 100644
--- a/pkg/tcpip/transport/udp/endpoint.go
+++ b/pkg/tcpip/transport/udp/endpoint.go
@@ -108,7 +108,6 @@ type endpoint struct {
 	multicastLoop  bool
 	portFlags      ports.Flags
 	bindToDevice   tcpip.NICID
-	noChecksum     bool
 
 	lastErrorMu sync.Mutex   `state:"nosave"`
 	lastError   *tcpip.Error `state:".(string)"`
@@ -550,7 +549,7 @@ func (e *endpoint) write(p tcpip.Payloader, opts tcpip.WriteOptions) (int64, <-c
 	localPort := e.ID.LocalPort
 	sendTOS := e.sendTOS
 	owner := e.owner
-	noChecksum := e.noChecksum
+	noChecksum := e.SocketOptions().GetNoChecksum()
 	lockReleased = true
 	e.mu.RUnlock()
 
@@ -583,11 +582,6 @@ func (e *endpoint) SetSockOptBool(opt tcpip.SockOptBool, v bool) *tcpip.Error {
 		e.multicastLoop = v
 		e.mu.Unlock()
 
-	case tcpip.NoChecksumOption:
-		e.mu.Lock()
-		e.noChecksum = v
-		e.mu.Unlock()
-
 	case tcpip.ReceiveTOSOption:
 		e.mu.Lock()
 		e.receiveTOS = v
@@ -858,12 +852,6 @@ func (e *endpoint) GetSockOptBool(opt tcpip.SockOptBool) (bool, *tcpip.Error) {
 		e.mu.RUnlock()
 		return v, nil
 
-	case tcpip.NoChecksumOption:
-		e.mu.RLock()
-		v := e.noChecksum
-		e.mu.RUnlock()
-		return v, nil
-
 	case tcpip.ReceiveTOSOption:
 		e.mu.RLock()
 		v := e.receiveTOS
diff --git a/pkg/tcpip/transport/udp/udp_test.go b/pkg/tcpip/transport/udp/udp_test.go
index 492e277a8..1233bab14 100644
--- a/pkg/tcpip/transport/udp/udp_test.go
+++ b/pkg/tcpip/transport/udp/udp_test.go
@@ -1454,16 +1454,12 @@ func TestNoChecksum(t *testing.T) {
 			c.createEndpointForFlow(flow)
 
 			// Disable the checksum generation.
-			if err := c.ep.SetSockOptBool(tcpip.NoChecksumOption, true); err != nil {
-				t.Fatalf("SetSockOptBool failed: %s", err)
-			}
+			c.ep.SocketOptions().SetNoChecksum(true)
 			// This option is effective on IPv4 only.
 			testWrite(c, flow, checker.UDP(checker.NoChecksum(flow.isV4())))
 
 			// Enable the checksum generation.
-			if err := c.ep.SetSockOptBool(tcpip.NoChecksumOption, false); err != nil {
-				t.Fatalf("SetSockOptBool failed: %s", err)
-			}
+			c.ep.SocketOptions().SetNoChecksum(false)
 			testWrite(c, flow, checker.UDP(checker.NoChecksum(false)))
 		})
 	}
diff --git a/test/syscalls/linux/socket_generic.cc b/test/syscalls/linux/socket_generic.cc
index c81ba031d..d17192c36 100644
--- a/test/syscalls/linux/socket_generic.cc
+++ b/test/syscalls/linux/socket_generic.cc
@@ -819,7 +819,7 @@ TEST_P(AllSocketPairTest, GetSockoptProtocol) {
 }
 
 TEST_P(AllSocketPairTest, SetAndGetBooleanSocketOptions) {
-  int sock_opts[] = {SO_BROADCAST, SO_PASSCRED};
+  int sock_opts[] = {SO_BROADCAST, SO_PASSCRED, SO_NO_CHECK};
   for (int sock_opt : sock_opts) {
     auto sockets = ASSERT_NO_ERRNO_AND_VALUE(NewSocketPair());
     int enable = -1;