Support for receiving outbound packets in AF_PACKET.

Updates #173

PiperOrigin-RevId: 322665518

2 files changed, 23 insertions, 0 deletions

diff --git a/pkg/tcpip/link/waitable/waitable.go b/pkg/tcpip/link/waitable/waitable.go
index 24a8dc2eb..b152a0f26 100644
--- a/pkg/tcpip/link/waitable/waitable.go
+++ b/pkg/tcpip/link/waitable/waitable.go
@@ -60,6 +60,15 @@ func (e *Endpoint) DeliverNetworkPacket(remote, local tcpip.LinkAddress, protoco
 	e.dispatchGate.Leave()
 }
 
+// DeliverOutboundPacket implements stack.NetworkDispatcher.DeliverOutboundPacket.
+func (e *Endpoint) DeliverOutboundPacket(remote, local tcpip.LinkAddress, protocol tcpip.NetworkProtocolNumber, pkt *stack.PacketBuffer) {
+	if !e.dispatchGate.Enter() {
+		return
+	}
+	e.dispatcher.DeliverOutboundPacket(remote, local, protocol, pkt)
+	e.dispatchGate.Leave()
+}
+
 // Attach implements stack.LinkEndpoint.Attach. It saves the dispatcher and
 // registers with the lower endpoint as its dispatcher so that "e" is called
 // for inbound packets.
@@ -153,3 +162,8 @@ func (e *Endpoint) Wait() {}
 func (e *Endpoint) ARPHardwareType() header.ARPHardwareType {
 	return e.lower.ARPHardwareType()
 }
+
+// AddHeader implements stack.LinkEndpoint.AddHeader.
+func (e *Endpoint) AddHeader(local, remote tcpip.LinkAddress, protocol tcpip.NetworkProtocolNumber, pkt *stack.PacketBuffer) {
+	e.lower.AddHeader(local, remote, protocol, pkt)
+}
diff --git a/pkg/tcpip/link/waitable/waitable_test.go b/pkg/tcpip/link/waitable/waitable_test.go
index ffb2354be..c448a888f 100644
--- a/pkg/tcpip/link/waitable/waitable_test.go
+++ b/pkg/tcpip/link/waitable/waitable_test.go
@@ -40,6 +40,10 @@ func (e *countedEndpoint) DeliverNetworkPacket(remote, local tcpip.LinkAddress,
 	e.dispatchCount++
 }
 
+func (e *countedEndpoint) DeliverOutboundPacket(remote, local tcpip.LinkAddress, protocol tcpip.NetworkProtocolNumber, pkt *stack.PacketBuffer) {
+	panic("unimplemented")
+}
+
 func (e *countedEndpoint) Attach(dispatcher stack.NetworkDispatcher) {
 	e.attachCount++
 	e.dispatcher = dispatcher
@@ -90,6 +94,11 @@ func (*countedEndpoint) ARPHardwareType() header.ARPHardwareType {
 // Wait implements stack.LinkEndpoint.Wait.
 func (*countedEndpoint) Wait() {}
 
+// AddHeader implements stack.LinkEndpoint.AddHeader.
+func (e *countedEndpoint) AddHeader(local, remote tcpip.LinkAddress, protocol tcpip.NetworkProtocolNumber, pkt *stack.PacketBuffer) {
+	panic("unimplemented")
+}
+
 func TestWaitWrite(t *testing.T) {
 	ep := &countedEndpoint{}
 	wep := New(ep)