Make HandleLocal apply to all non-loopback interfaces.

HandleLocal is very similar conceptually to MULTICAST_LOOP, so we can unify
the implementations. This has the benefit of making HandleLocal apply even when
the fdbased link endpoint isn't in use.

In addition, move looping logic to route creation so that it doesn't need to be
run for each packet. This should improve performance.

PiperOrigin-RevId: 238099480
Change-Id: I72839f16f25310471453bc9d3fb8544815b25c23

1 files changed, 0 insertions, 15 deletions

diff --git a/pkg/tcpip/link/fdbased/endpoint.go b/pkg/tcpip/link/fdbased/endpoint.go
index fa980716d..d726551b0 100644
--- a/pkg/tcpip/link/fdbased/endpoint.go
+++ b/pkg/tcpip/link/fdbased/endpoint.go
@@ -100,11 +100,6 @@ type endpoint struct {
 	inboundDispatcher linkDispatcher
 	dispatcher        stack.NetworkDispatcher
 
-	// handleLocal indicates whether packets destined to itself should be
-	// handled by the netstack internally (true) or be forwarded to the FD
-	// endpoint (false).
-	handleLocal bool
-
 	// packetDispatchMode controls the packet dispatcher used by this
 	// endpoint.
 	packetDispatchMode PacketDispatchMode
@@ -128,7 +123,6 @@ type Options struct {
 	Address            tcpip.LinkAddress
 	SaveRestore        bool
 	DisconnectOk       bool
-	HandleLocal        bool
 	PacketDispatchMode PacketDispatchMode
 }
 
@@ -168,7 +162,6 @@ func New(opts *Options) tcpip.LinkEndpointID {
 		closed:             opts.ClosedFunc,
 		addr:               opts.Address,
 		hdrSize:            hdrSize,
-		handleLocal:        opts.HandleLocal,
 		packetDispatchMode: opts.PacketDispatchMode,
 	}
 
@@ -256,14 +249,6 @@ func (e *endpoint) LinkAddress() tcpip.LinkAddress {
 // WritePacket writes outbound packets to the file descriptor. If it is not
 // currently writable, the packet is dropped.
 func (e *endpoint) WritePacket(r *stack.Route, hdr buffer.Prependable, payload buffer.VectorisedView, protocol tcpip.NetworkProtocolNumber) *tcpip.Error {
-	if e.handleLocal && r.LocalAddress != "" && r.LocalAddress == r.RemoteAddress {
-		views := make([]buffer.View, 1, 1+len(payload.Views()))
-		views[0] = hdr.View()
-		views = append(views, payload.Views()...)
-		vv := buffer.NewVectorisedView(len(views[0])+payload.Size(), views)
-		e.dispatcher.DeliverNetworkPacket(e, r.RemoteLinkAddress, r.LocalLinkAddress, protocol, vv)
-		return nil
-	}
 	if e.hdrSize > 0 {
 		// Add ethernet header if needed.
 		eth := header.Ethernet(hdr.Prepend(header.EthernetMinimumSize))