11 files changed, 46 insertions, 0 deletions
diff --git a/pkg/tcpip/link/channel/channel.go b/pkg/tcpip/link/channel/channel.go
index f26c857eb..d02eea93c 100644
--- a/pkg/tcpip/link/channel/channel.go
+++ b/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{} }
diff --git a/pkg/tcpip/link/ethernet/ethernet.go b/pkg/tcpip/link/ethernet/ethernet.go
index b9db273d0..8211a2031 100644
--- a/pkg/tcpip/link/ethernet/ethernet.go
+++ b/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)
+}
diff --git a/pkg/tcpip/link/fdbased/endpoint.go b/pkg/tcpip/link/fdbased/endpoint.go
index 48356c343..058242f96 100644
--- a/pkg/tcpip/link/fdbased/endpoint.go
+++ b/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 {
diff --git a/pkg/tcpip/link/loopback/loopback.go b/pkg/tcpip/link/loopback/loopback.go
index 7012d8829..d7bbfa639 100644
--- a/pkg/tcpip/link/loopback/loopback.go
+++ b/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{} }
diff --git a/pkg/tcpip/link/muxed/injectable.go b/pkg/tcpip/link/muxed/injectable.go
index 3e2a1aa94..844f5959b 100644
--- a/pkg/tcpip/link/muxed/injectable.go
+++ b/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{
diff --git a/pkg/tcpip/link/nested/nested.go b/pkg/tcpip/link/nested/nested.go
index 3e816b0c7..14cb96d63 100644
--- a/pkg/tcpip/link/nested/nested.go
+++ b/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)
+}
diff --git a/pkg/tcpip/link/pipe/pipe.go b/pkg/tcpip/link/pipe/pipe.go
index 5030b6ba1..3ed0aa3fe 100644
--- a/pkg/tcpip/link/pipe/pipe.go
+++ b/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{} }
diff --git a/pkg/tcpip/link/qdisc/fifo/endpoint.go b/pkg/tcpip/link/qdisc/fifo/endpoint.go
index 40bd5560b..dc63e5fb0 100644
--- a/pkg/tcpip/link/qdisc/fifo/endpoint.go
+++ b/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)
+}
diff --git a/pkg/tcpip/link/sharedmem/sharedmem.go b/pkg/tcpip/link/sharedmem/sharedmem.go
index 30cf659b8..66efe6472 100644
--- a/pkg/tcpip/link/sharedmem/sharedmem.go
+++ b/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 {
diff --git a/pkg/tcpip/link/waitable/waitable.go b/pkg/tcpip/link/waitable/waitable.go
index a95602aa5..13900205d 100644
--- a/pkg/tcpip/link/waitable/waitable.go
+++ b/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{} }
diff --git a/pkg/tcpip/stack/registration.go b/pkg/tcpip/stack/registration.go
index dfe2c886f..57b3348b2 100644
--- a/pkg/tcpip/stack/registration.go
+++ b/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