Function TestIsSelfDst

wgengine/netstack/netstack_test.go:1461–1552

TestIsSelfDst verifies that isSelfDst correctly identifies packets whose destination IP is a local Tailscale IP assigned to this node.

(t *testing.T)

// TestIsSelfDst verifies that isSelfDst correctly identifies packets whose
// destination IP is a local Tailscale IP assigned to this node.
func TestIsSelfDst(t *testing.T) {
	var (
		selfIP4   = netip.MustParseAddr("100.64.1.2")
		selfIP6   = netip.MustParseAddr("fd7a:115c:a1e0::123")
		remoteIP4 = netip.MustParseAddr("100.64.99.88")
		remoteIP6 = netip.MustParseAddr("fd7a:115c:a1e0::99")
	)

	ns := makeNetstack(t, func(impl *Impl) {
		impl.ProcessLocalIPs = true
		impl.atomicIsLocalIPFunc.Store(func(addr netip.Addr) bool {
			return addr == selfIP4 || addr == selfIP6
		})
	})

	testCases := []struct {
		name     string
		src, dst netip.AddrPort
		want     bool
	}{
		{
			name: "self_to_self_v4",
			src:  netip.AddrPortFrom(selfIP4, 12345),
			dst:  netip.AddrPortFrom(selfIP4, 8081),
			want: true,
		},
		{
			name: "self_to_self_v6",
			src:  netip.AddrPortFrom(selfIP6, 12345),
			dst:  netip.AddrPortFrom(selfIP6, 8081),
			want: true,
		},
		{
			name: "remote_to_self_v4",
			src:  netip.AddrPortFrom(remoteIP4, 12345),
			dst:  netip.AddrPortFrom(selfIP4, 8081),
			want: true,
		},
		{
			name: "remote_to_self_v6",
			src:  netip.AddrPortFrom(remoteIP6, 12345),
			dst:  netip.AddrPortFrom(selfIP6, 8081),
			want: true,
		},
		{
			name: "self_to_remote_v4",
			src:  netip.AddrPortFrom(selfIP4, 12345),
			dst:  netip.AddrPortFrom(remoteIP4, 8081),
			want: false,
		},
		{
			name: "self_to_remote_v6",
			src:  netip.AddrPortFrom(selfIP6, 12345),
			dst:  netip.AddrPortFrom(remoteIP6, 8081),
			want: false,
		},
		{
			name: "remote_to_remote_v4",