Hide neighbor table kind from NetworkEndpoint

The network endpoint should not need to have logic to handle different
kinds of neighbor tables. Network endpoints can let the NIC know about
differnt neighbor discovery messages and let the NIC decide which table
to update.

This allows us to remove the LinkAddressCache interface.

PiperOrigin-RevId: 354812584

2 files changed, 8 insertions, 21 deletions

diff --git a/pkg/tcpip/network/arp/arp.go b/pkg/tcpip/network/arp/arp.go
index 5c79d6485..5fd4c5574 100644
--- a/pkg/tcpip/network/arp/arp.go
+++ b/pkg/tcpip/network/arp/arp.go
@@ -50,10 +50,8 @@ type endpoint struct {
 	// Must be accessed using atomic operations.
 	enabled uint32
 
-	nic           stack.NetworkInterface
-	linkAddrCache stack.LinkAddressCache
-	nud           stack.NUDHandler
-	stats         sharedStats
+	nic   stack.NetworkInterface
+	stats sharedStats
 }
 
 func (e *endpoint) Enable() tcpip.Error {
@@ -150,11 +148,7 @@ func (e *endpoint) HandlePacket(pkt *stack.PacketBuffer) {
 		remoteAddr := tcpip.Address(h.ProtocolAddressSender())
 		remoteLinkAddr := tcpip.LinkAddress(h.HardwareAddressSender())
 
-		if e.nud == nil {
-			e.linkAddrCache.AddLinkAddress(remoteAddr, remoteLinkAddr)
-		} else {
-			e.nud.HandleProbe(remoteAddr, ProtocolNumber, remoteLinkAddr, e)
-		}
+		e.nic.HandleNeighborProbe(remoteAddr, remoteLinkAddr, e)
 
 		respPkt := stack.NewPacketBuffer(stack.PacketBufferOptions{
 			ReserveHeaderBytes: int(e.nic.MaxHeaderLength()) + header.ARPSize,
@@ -194,14 +188,9 @@ func (e *endpoint) HandlePacket(pkt *stack.PacketBuffer) {
 		addr := tcpip.Address(h.ProtocolAddressSender())
 		linkAddr := tcpip.LinkAddress(h.HardwareAddressSender())
 
-		if e.nud == nil {
-			e.linkAddrCache.AddLinkAddress(addr, linkAddr)
-			return
-		}
-
 		// The solicited, override, and isRouter flags are not available for ARP;
 		// they are only available for IPv6 Neighbor Advertisements.
-		e.nud.HandleConfirmation(addr, linkAddr, stack.ReachabilityConfirmationFlags{
+		e.nic.HandleNeighborConfirmation(addr, linkAddr, stack.ReachabilityConfirmationFlags{
 			// Solicited and unsolicited (also referred to as gratuitous) ARP Replies
 			// are handled equivalently to a solicited Neighbor Advertisement.
 			Solicited: true,
@@ -234,12 +223,10 @@ func (*protocol) ParseAddresses(buffer.View) (src, dst tcpip.Address) {
 	return "", ""
 }
 
-func (p *protocol) NewEndpoint(nic stack.NetworkInterface, linkAddrCache stack.LinkAddressCache, nud stack.NUDHandler, dispatcher stack.TransportDispatcher) stack.NetworkEndpoint {
+func (p *protocol) NewEndpoint(nic stack.NetworkInterface, dispatcher stack.TransportDispatcher) stack.NetworkEndpoint {
 	e := &endpoint{
-		protocol:      p,
-		nic:           nic,
-		linkAddrCache: linkAddrCache,
-		nud:           nud,
+		protocol: p,
+		nic:      nic,
 	}
 
 	tcpip.InitStatCounters(reflect.ValueOf(&e.stats.localStats).Elem())
diff --git a/pkg/tcpip/network/arp/stats_test.go b/pkg/tcpip/network/arp/stats_test.go
index d3b56c635..65c708ac4 100644
--- a/pkg/tcpip/network/arp/stats_test.go
+++ b/pkg/tcpip/network/arp/stats_test.go
@@ -40,7 +40,7 @@ func TestMultiCounterStatsInitialization(t *testing.T) {
 	})
 	proto := s.NetworkProtocolInstance(ProtocolNumber).(*protocol)
 	var nic testInterface
-	ep := proto.NewEndpoint(&nic, nil, nil, nil).(*endpoint)
+	ep := proto.NewEndpoint(&nic, nil).(*endpoint)
 	// At this point, the Stack's stats and the NetworkEndpoint's stats are
 	// expected to be bound by a MultiCounterStat.
 	refStack := s.Stats()