Use different neighbor tables per network endpoint

This stores each protocol's neighbor state separately.

This change also removes the need for each neighbor entry to keep
track of their own link address resolver now that all the entries
in a cache will use the same resolver.

PiperOrigin-RevId: 354818155

1 files changed, 8 insertions, 6 deletions

diff --git a/pkg/tcpip/stack/route.go b/pkg/tcpip/stack/route.go
index 1c8ef6ed4..bab55ce49 100644
--- a/pkg/tcpip/stack/route.go
+++ b/pkg/tcpip/stack/route.go
@@ -53,7 +53,7 @@ type Route struct {
 
 	// linkRes is set if link address resolution is enabled for this protocol on
 	// the route's NIC.
-	linkRes LinkAddressResolver
+	linkRes linkResolver
 }
 
 type routeInfo struct {
@@ -184,11 +184,11 @@ func makeRoute(netProto tcpip.NetworkProtocolNumber, gateway, localAddr, remoteA
 		return r
 	}
 
-	if r.linkRes == nil {
+	if r.linkRes.resolver == nil {
 		return r
 	}
 
-	if linkAddr, ok := r.linkRes.ResolveStaticAddress(r.RemoteAddress); ok {
+	if linkAddr, ok := r.linkRes.resolver.ResolveStaticAddress(r.RemoteAddress); ok {
 		r.ResolveWith(linkAddr)
 		return r
 	}
@@ -362,7 +362,7 @@ func (r *Route) resolvedFields(afterResolve func(ResolvedFieldsResult)) (RouteIn
 	}
 
 	afterResolveFields := fields
-	linkAddr, ch, err := r.outgoingNIC.getNeighborLinkAddress(r.nextHop(), linkAddressResolutionRequestLocalAddr, r.linkRes, func(r LinkResolutionResult) {
+	linkAddr, ch, err := r.linkRes.getNeighborLinkAddress(r.nextHop(), linkAddressResolutionRequestLocalAddr, func(r LinkResolutionResult) {
 		if afterResolve != nil {
 			if r.Success {
 				afterResolveFields.RemoteLinkAddress = r.LinkAddress
@@ -400,7 +400,7 @@ func (r *Route) IsResolutionRequired() bool {
 }
 
 func (r *Route) isResolutionRequiredRLocked() bool {
-	return len(r.mu.remoteLinkAddress) == 0 && r.linkRes != nil && r.isValidForOutgoingRLocked() && !r.local()
+	return len(r.mu.remoteLinkAddress) == 0 && r.linkRes.resolver != nil && r.isValidForOutgoingRLocked() && !r.local()
 }
 
 func (r *Route) isValidForOutgoing() bool {
@@ -528,5 +528,7 @@ func (r *Route) IsOutboundBroadcast() bool {
 // "Reachable" is defined as having full-duplex communication between the
 // local and remote ends of the route.
 func (r *Route) ConfirmReachable() {
-	r.outgoingNIC.confirmReachable(r.nextHop())
+	if r.linkRes.resolver != nil {
+		r.linkRes.confirmReachable(r.nextHop())
+	}
 }