Merge f8c01f0bf3 into 8a8ad2be81

We should not enlarge the socket buffers when:
 - We are using a test dial (there are no buffers to enlarge).
 - A connection has been initialized with socket options which means
   that the user could have specified fixed buffer sizes.

conn.go

@@ -250,10 +250,10 @@ func (cc *Conn) Flush() error {
 	}
 	defer func() { _ = closer() }()
 
-	if err = cc.enlargeWriteBuffer(conn); err != nil {
+	if err := cc.enlargeWriteBuffer(conn); err != nil {
 		return err
 	}
-	if err = cc.enlargeReadBuffer(conn); err != nil {
+	if err := cc.enlargeReadBuffer(conn); err != nil {
 		return err
 	}
 
@@ -440,6 +440,22 @@ func (cc *Conn) getMessageSize() int {
 	return total
 }
 
+// canEnlargeBuffers returns true if the connection can automatically enlarge
+// the write and read buffers of the netlink connection.
+func (cc *Conn) canEnlargeBuffers() bool {
+	// If there are sock options, we assume that the user has already set the
+	// buffers to a fixed size.
+	if len(cc.sockOptions) > 0 {
+		return false
+	}
+
+	if cc.TestDial != nil {
+		return false
+	}
+
+	return true
+}
+
 // enlargeWriteBuffer automatically sets the write buffer of the given
 // connection to the accumulated message size. This is only done if the current
 // write buffer is smaller than the message size.
@@ -453,6 +469,10 @@ func (cc *Conn) getMessageSize() int {
 // TODO: Update this function to mimic the behavior of nftables once our
 // socket library supports multiple iovec entries.
 func (cc *Conn) enlargeWriteBuffer(conn *netlink.Conn) error {
+	if !cc.canEnlargeBuffers() {
+		return nil
+	}
+
 	messageSize := cc.getMessageSize()
 	writeBuffer, err := conn.WriteBuffer()
 	if err != nil {
@@ -481,6 +501,10 @@ func (cc *Conn) getDefaultEchoReadBuffer() int {
 //
 // See https://git.netfilter.org/nftables/tree/src/mnl.c?id=713592c6008a8c589a00d3d3d2e49709ff2de62c#n426
 func (cc *Conn) enlargeReadBuffer(conn *netlink.Conn) error {
+	if !cc.canEnlargeBuffers() {
+		return nil
+	}
+
 	var bufferSize int
 
 	// If there are any messages with the Echo flag, we initialize the buffer size

expr/ct.go

@@ -110,6 +110,12 @@ const (
 	CtStateUDPREPLIED
 )
 
+const (
+	// https://git.netfilter.org/libnftnl/tree/src/expr/ct.c?id=116e95aa7b6358c917de8c69f6f173874030b46b#n31
+	CtDirOriginal = iota
+	CtDirReply
+)
+
 // https://git.netfilter.org/libnftnl/tree/src/obj/ct_timeout.c?id=116e95aa7b6358c917de8c69f6f173874030b46b#n57
 var CtStateUDPTimeoutDefaults CtStatePolicyTimeout = map[uint16]uint32{
 	CtStateUDPUNREPLIED: 30,
@@ -122,6 +128,7 @@ type Ct struct {
 	SourceRegister bool
 	Key            CtKey
 	Direction      uint32
+	OptDirection   bool
 }
 
 func (e *Ct) marshal(fam byte) ([]byte, error) {
@@ -165,10 +172,16 @@ func (e *Ct) marshalData(fam byte) ([]byte, error) {
 	exprData = append(exprData, regData...)
 
 	switch e.Key {
+	case CtKeyPKTS, CtKeyBYTES, CtKeyAVGPKT, CtKeyL3PROTOCOL, CtKeyPROTOCOL:
+		if !e.OptDirection {
+			break
+		}
+
+		fallthrough
 	case CtKeySRC, CtKeyDST, CtKeyPROTOSRC, CtKeyPROTODST, CtKeySRCIP, CtKeyDSTIP, CtKeySRCIP6, CtKeyDSTIP6:
 		regData, err = netlink.MarshalAttributes(
 			[]netlink.Attribute{
-				{Type: unix.NFTA_CT_DIRECTION, Data: binaryutil.BigEndian.PutUint32(e.Direction)},
+				{Type: unix.NFTA_CT_DIRECTION, Data: []byte{uint8(e.Direction)}},
 			},
 		)
 		if err != nil {
@@ -186,6 +199,8 @@ func (e *Ct) unmarshal(fam byte, data []byte) error {
 		return err
 	}
 	ad.ByteOrder = binary.BigEndian
+
+	var hasDirection bool
 	for ad.Next() {
 		switch ad.Type() {
 		case unix.NFTA_CT_KEY:
@@ -193,12 +208,19 @@ func (e *Ct) unmarshal(fam byte, data []byte) error {
 		case unix.NFTA_CT_DREG:
 			e.Register = ad.Uint32()
 		case unix.NFTA_CT_DIRECTION:
-			e.Direction = ad.Uint32()
+			e.Direction = uint32(ad.Uint8())
+			hasDirection = true
 		case unix.NFTA_CT_SREG:
 			e.SourceRegister = true
 			e.Register = ad.Uint32()
 		}
 	}
+
+	switch e.Key {
+	case CtKeyPKTS, CtKeyBYTES, CtKeyAVGPKT, CtKeyL3PROTOCOL, CtKeyPROTOCOL:
+		e.OptDirection = hasDirection
+	}
+
 	return ad.Err()
 }
 

expr/ct_test.go

@@ -78,6 +78,22 @@ func TestCt(t *testing.T) {
 				Direction: 1,
 			},
 		},
+		{
+			name: "Unmarshal Ct packets direction original case",
+			ct: Ct{
+				Register:     1,
+				Key:          CtKeyPKTS,
+				Direction:    CtDirOriginal,
+				OptDirection: true,
+			},
+		},
+		{
+			name: "Unmarshal Ct bytes without direction case",
+			ct: Ct{
+				Register: 1,
+				Key:      CtKeyBYTES,
+			},
+		},
 	}
 
 	for _, tt := range tests {

go.mod

@@ -12,6 +12,6 @@ require (
 
 require (
 	github.com/mdlayher/socket v0.5.0 // indirect
-	golang.org/x/net v0.37.0 // indirect
+	golang.org/x/net v0.38.0 // indirect
 	golang.org/x/sync v0.6.0 // indirect
 )

go.sum

@@ -8,8 +8,8 @@ github.com/vishvananda/netlink v1.3.0 h1:X7l42GfcV4S6E4vHTsw48qbrV+9PVojNfIhZcwQ
 github.com/vishvananda/netlink v1.3.0/go.mod h1:i6NetklAujEcC6fK0JPjT8qSwWyO0HLn4UKG+hGqeJs=
 github.com/vishvananda/netns v0.0.4 h1:Oeaw1EM2JMxD51g9uhtC0D7erkIjgmj8+JZc26m1YX8=
 github.com/vishvananda/netns v0.0.4/go.mod h1:SpkAiCQRtJ6TvvxPnOSyH3BMl6unz3xZlaprSwhNNJM=
-golang.org/x/net v0.37.0 h1:1zLorHbz+LYj7MQlSf1+2tPIIgibq2eL5xkrGk6f+2c=
+golang.org/x/net v0.38.0 h1:vRMAPTMaeGqVhG5QyLJHqNDwecKTomGeqbnfZyKlBI8=
-golang.org/x/net v0.37.0/go.mod h1:ivrbrMbzFq5J41QOQh0siUuly180yBYtLp+CKbEaFx8=
+golang.org/x/net v0.38.0/go.mod h1:ivrbrMbzFq5J41QOQh0siUuly180yBYtLp+CKbEaFx8=
 golang.org/x/sync v0.6.0 h1:5BMeUDZ7vkXGfEr1x9B4bRcTH4lpkTkpdh0T/J+qjbQ=
 golang.org/x/sync v0.6.0/go.mod h1:Czt+wKu1gCyEFDUtn0jG5QVvpJ6rzVqr5aXyt9drQfk=
 golang.org/x/sys v0.2.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=