Support GetLinkAddress with neighborCache

Test: integration_test.TestGetLinkAddress
PiperOrigin-RevId: 352119404

1 files changed, 21 insertions, 0 deletions

diff --git a/pkg/tcpip/stack/stack_test.go b/pkg/tcpip/stack/stack_test.go
index 4a3f937e3..82ee066e6 100644
--- a/pkg/tcpip/stack/stack_test.go
+++ b/pkg/tcpip/stack/stack_test.go
@@ -4357,3 +4357,24 @@ func TestClearNeighborCacheOnNICDisable(t *testing.T) {
 		t.Fatalf("got len(neighbors) = %d, want = 0; neighbors = %#v", len(neighbors), neighbors)
 	}
 }
+
+func TestGetLinkAddressErrors(t *testing.T) {
+	const (
+		nicID        = 1
+		unknownNICID = nicID + 1
+	)
+
+	s := stack.New(stack.Options{
+		NetworkProtocols: []stack.NetworkProtocolFactory{ipv4.NewProtocol},
+	})
+	if err := s.CreateNIC(nicID, channel.New(0, 0, "")); err != nil {
+		t.Fatalf("CreateNIC(%d, _) = %s", nicID, err)
+	}
+
+	if addr, _, err := s.GetLinkAddress(unknownNICID, "", "", ipv4.ProtocolNumber, nil); err != tcpip.ErrUnknownNICID {
+		t.Errorf("got s.GetLinkAddress(%d, '', '', %d, nil) = (%s, _, %s), want = (_, _, %s)", unknownNICID, ipv4.ProtocolNumber, addr, err, tcpip.ErrUnknownNICID)
+	}
+	if addr, _, err := s.GetLinkAddress(nicID, "", "", ipv4.ProtocolNumber, nil); err != tcpip.ErrNotSupported {
+		t.Errorf("got s.GetLinkAddress(%d, '', '', %d, nil) = (%s, _, %s), want = (_, _, %s)", unknownNICID, ipv4.ProtocolNumber, addr, err, tcpip.ErrNotSupported)
+	}
+}