Add LinkEndpoint.WriteRawPacket with stubs

...returning unsupported errors.

PiperOrigin-RevId: 393388991

pkg/tcpip/link/channel/channel.go

@@ -290,3 +290,6 @@ func (*Endpoint) ARPHardwareType() header.ARPHardwareType {
 // AddHeader implements stack.LinkEndpoint.AddHeader.
 func (*Endpoint) AddHeader(tcpip.LinkAddress, tcpip.LinkAddress, tcpip.NetworkProtocolNumber, *stack.PacketBuffer) {
 }
+
+// WriteRawPacket implements stack.LinkEndpoint.
+func (*Endpoint) WriteRawPacket(*stack.PacketBuffer) tcpip.Error { return &tcpip.ErrNotSupported{} }

pkg/tcpip/link/ethernet/ethernet.go

@@ -112,3 +112,8 @@ func (*Endpoint) AddHeader(local, remote tcpip.LinkAddress, proto tcpip.NetworkP
 	}
 	eth.Encode(&fields)
 }
+
+// WriteRawPacket implements stack.LinkEndpoint.
+func (e *Endpoint) WriteRawPacket(pkt *stack.PacketBuffer) tcpip.Error {
+	return e.Endpoint.WriteRawPacket(pkt)
+}

pkg/tcpip/link/fdbased/endpoint.go

@@ -505,6 +505,9 @@ func (e *endpoint) AddHeader(local, remote tcpip.LinkAddress, protocol tcpip.Net
 	}
 }
 
+// WriteRawPacket implements stack.LinkEndpoint.
+func (*endpoint) WriteRawPacket(*stack.PacketBuffer) tcpip.Error { return &tcpip.ErrNotSupported{} }
+
 // WritePacket writes outbound packets to the file descriptor. If it is not
 // currently writable, the packet is dropped.
 func (e *endpoint) WritePacket(r stack.RouteInfo, protocol tcpip.NetworkProtocolNumber, pkt *stack.PacketBuffer) tcpip.Error {

pkg/tcpip/link/loopback/loopback.go

@@ -103,3 +103,6 @@ func (*endpoint) ARPHardwareType() header.ARPHardwareType {
 
 func (e *endpoint) AddHeader(local, remote tcpip.LinkAddress, protocol tcpip.NetworkProtocolNumber, pkt *stack.PacketBuffer) {
 }
+
+// WriteRawPacket implements stack.LinkEndpoint.
+func (*endpoint) WriteRawPacket(*stack.PacketBuffer) tcpip.Error { return &tcpip.ErrNotSupported{} }

pkg/tcpip/link/muxed/injectable.go

@@ -131,6 +131,11 @@ func (*InjectableEndpoint) ARPHardwareType() header.ARPHardwareType {
 func (*InjectableEndpoint) AddHeader(local, remote tcpip.LinkAddress, protocol tcpip.NetworkProtocolNumber, pkt *stack.PacketBuffer) {
 }
 
+// WriteRawPacket implements stack.LinkEndpoint.
+func (*InjectableEndpoint) WriteRawPacket(*stack.PacketBuffer) tcpip.Error {
+	return &tcpip.ErrNotSupported{}
+}
+
 // NewInjectableEndpoint creates a new multi-endpoint injectable endpoint.
 func NewInjectableEndpoint(routes map[tcpip.Address]stack.InjectableLinkEndpoint) *InjectableEndpoint {
 	return &InjectableEndpoint{

pkg/tcpip/link/nested/nested.go

@@ -152,3 +152,8 @@ func (e *Endpoint) ARPHardwareType() header.ARPHardwareType {
 func (e *Endpoint) AddHeader(local, remote tcpip.LinkAddress, protocol tcpip.NetworkProtocolNumber, pkt *stack.PacketBuffer) {
 	e.child.AddHeader(local, remote, protocol, pkt)
 }
+
+// WriteRawPacket implements stack.LinkEndpoint.
+func (e *Endpoint) WriteRawPacket(pkt *stack.PacketBuffer) tcpip.Error {
+	return e.child.WriteRawPacket(pkt)
+}

pkg/tcpip/link/pipe/pipe.go

@@ -121,3 +121,6 @@ func (*Endpoint) ARPHardwareType() header.ARPHardwareType {
 // AddHeader implements stack.LinkEndpoint.
 func (*Endpoint) AddHeader(_, _ tcpip.LinkAddress, _ tcpip.NetworkProtocolNumber, _ *stack.PacketBuffer) {
 }
+
+// WriteRawPacket implements stack.LinkEndpoint.
+func (*Endpoint) WriteRawPacket(*stack.PacketBuffer) tcpip.Error { return &tcpip.ErrNotSupported{} }

pkg/tcpip/link/qdisc/fifo/endpoint.go

@@ -228,3 +228,8 @@ func (e *endpoint) ARPHardwareType() header.ARPHardwareType {
 func (e *endpoint) AddHeader(local, remote tcpip.LinkAddress, protocol tcpip.NetworkProtocolNumber, pkt *stack.PacketBuffer) {
 	e.lower.AddHeader(local, remote, protocol, pkt)
 }
+
+// WriteRawPacket implements stack.LinkEndpoint.
+func (e *endpoint) WriteRawPacket(pkt *stack.PacketBuffer) tcpip.Error {
+	return e.lower.WriteRawPacket(pkt)
+}

pkg/tcpip/link/sharedmem/sharedmem.go

@@ -202,6 +202,9 @@ func (e *endpoint) AddHeader(local, remote tcpip.LinkAddress, protocol tcpip.Net
 	eth.Encode(ethHdr)
 }
 
+// WriteRawPacket implements stack.LinkEndpoint.
+func (*endpoint) WriteRawPacket(*stack.PacketBuffer) tcpip.Error { return &tcpip.ErrNotSupported{} }
+
 // WritePacket writes outbound packets to the file descriptor. If it is not
 // currently writable, the packet is dropped.
 func (e *endpoint) WritePacket(r stack.RouteInfo, protocol tcpip.NetworkProtocolNumber, pkt *stack.PacketBuffer) tcpip.Error {

pkg/tcpip/link/waitable/waitable.go

@@ -155,3 +155,6 @@ func (e *Endpoint) ARPHardwareType() header.ARPHardwareType {
 func (e *Endpoint) AddHeader(local, remote tcpip.LinkAddress, protocol tcpip.NetworkProtocolNumber, pkt *stack.PacketBuffer) {
 	e.lower.AddHeader(local, remote, protocol, pkt)
 }
+
+// WriteRawPacket implements stack.LinkEndpoint.
+func (*Endpoint) WriteRawPacket(*stack.PacketBuffer) tcpip.Error { return &tcpip.ErrNotSupported{} }

pkg/tcpip/link/waitable/waitable_test.go

@@ -80,6 +80,11 @@ func (e *countedEndpoint) WritePackets(_ stack.RouteInfo, pkts stack.PacketBuffe
 	return pkts.Len(), nil
 }
 
+// WriteRawPacket implements stack.LinkEndpoint.
+func (*countedEndpoint) WriteRawPacket(*stack.PacketBuffer) tcpip.Error {
+	return &tcpip.ErrNotSupported{}
+}
+
 // ARPHardwareType implements stack.LinkEndpoint.ARPHardwareType.
 func (*countedEndpoint) ARPHardwareType() header.ARPHardwareType {
 	panic("unimplemented")

pkg/tcpip/network/internal/testutil/testutil.go

@@ -101,6 +101,11 @@ func (*MockLinkEndpoint) ARPHardwareType() header.ARPHardwareType { return heade
 func (*MockLinkEndpoint) AddHeader(_, _ tcpip.LinkAddress, _ tcpip.NetworkProtocolNumber, _ *stack.PacketBuffer) {
 }
 
+// WriteRawPacket implements stack.LinkEndpoint.
+func (*MockLinkEndpoint) WriteRawPacket(*stack.PacketBuffer) tcpip.Error {
+	return &tcpip.ErrNotSupported{}
+}
+
 // MakeRandPkt generates a randomized packet. transportHeaderLength indicates
 // how many random bytes will be copied in the Transport Header.
 // extraHeaderReserveLength indicates how much extra space will be reserved for

pkg/tcpip/stack/forwarding_test.go

@@ -342,6 +342,10 @@ func (e *fwdTestLinkEndpoint) WritePackets(r RouteInfo, pkts PacketBufferList, p
 	return n, nil
 }
 
+func (*fwdTestLinkEndpoint) WriteRawPacket(*PacketBuffer) tcpip.Error {
+	return &tcpip.ErrNotSupported{}
+}
+
 // Wait implements stack.LinkEndpoint.Wait.
 func (*fwdTestLinkEndpoint) Wait() {}
 

pkg/tcpip/stack/registration.go

@@ -846,6 +846,14 @@ type LinkEndpoint interface {
 	// offload is enabled. If it will be used for something else, syscall filters
 	// may need to be updated.
 	WritePackets(RouteInfo, PacketBufferList, tcpip.NetworkProtocolNumber) (int, tcpip.Error)
+
+	// WriteRawPacket writes a packet directly to the link.
+	//
+	// If the link-layer has its own header, the payload must already include the
+	// header.
+	//
+	// WriteRawPacket takes ownership of the packet.
+	WriteRawPacket(*PacketBuffer) tcpip.Error
 }
 
 // InjectableLinkEndpoint is a LinkEndpoint where inbound packets are