ipn/backend.go

@@ -118,6 +118,17 @@ type Notify struct {
 	Prefs         *PrefsView         // if non-nil && Valid, the new or current preferences
 	NetMap        *netmap.NetworkMap // if non-nil, the new or current netmap
 
+	// SelfChange, if non-nil, indicates that this node's own [tailcfg.Node]
+	// has changed: addresses, name, key expiry, capabilities, etc. It carries
+	// the new self node so reactive consumers (containerboot, kube agents,
+	// sniproxy, etc.) can read the current self state without watching the
+	// full netmap.
+	//
+	// Consumers that need additional state (peers, DNS config, packet
+	// filter) should react to SelfChange by fetching the relevant bits on
+	// demand via [LocalClient].
+	SelfChange *tailcfg.Node `json:",omitzero"`
+
 	// PeerChanges, if non-nil, is a list of [tailcfg.PeerChange] that have occurred since the last
 	// full netmap update. This is sent in lieu of a full NetMap when [NotifyPeerChanges] is set in
 	// the session's mask and a netmap update is derived from an incremental MapResponse.
@@ -196,6 +207,9 @@ func (n Notify) String() string {
 	if n.NetMap != nil {
 		sb.WriteString("NetMap{...} ")
 	}
+	if n.SelfChange != nil {
+		fmt.Fprintf(&sb, "SelfChange(%v) ", n.SelfChange.StableID)
+	}
 	if n.PeerChanges != nil {
 		fmt.Fprintf(&sb, "PeerChanges(%d) ", len(n.PeerChanges))
 	}

ipn/ipnlocal/bus.go

@@ -205,6 +205,7 @@ func isNotableNotify(n *ipn.Notify) bool {
 		n.Prefs != nil ||
 		n.ErrMessage != nil ||
 		n.LoginFinished != nil ||
+		n.SelfChange != nil ||
 		!n.DriveShares.IsNil() ||
 		n.Health != nil ||
 		len(n.IncomingFiles) > 0 ||

ipn/ipnlocal/bus_test.go

@@ -32,6 +32,7 @@ func TestIsNotableNotify(t *testing.T) {
 		{"netmap", &ipn.Notify{NetMap: new(netmap.NetworkMap)}, false},
 		{"peerchanges", &ipn.Notify{PeerChanges: []*tailcfg.PeerChange{{}}}, false},
 		{"engine", &ipn.Notify{Engine: new(ipn.EngineStatus)}, false},
+		{"selfchange", &ipn.Notify{SelfChange: &tailcfg.Node{}}, true},
 	}
 
 	// Then for all other fields, assume they're notable.
@@ -41,7 +42,7 @@ func TestIsNotableNotify(t *testing.T) {
 	for sf := range rt.Fields() {
 		n := &ipn.Notify{}
 		switch sf.Name {
-		case "_", "NetMap", "PeerChanges", "Engine", "Version":
+		case "_", "NetMap", "PeerChanges", "SelfChange", "Engine", "Version":
 			// Already covered above or not applicable.
 			continue
 		case "DriveShares":

ipn/ipnlocal/local.go

@@ -1897,7 +1897,15 @@ func (b *LocalBackend) setControlClientStatusLocked(c controlclient.Client, st c
 		// Update the DERP map in the health package, which uses it for health notifications
 		b.health.SetDERPMap(st.NetMap.DERPMap)
 
-		b.sendLocked(ipn.Notify{NetMap: st.NetMap})
+		// Notify watchers that the self node may have changed. Reactive
+		// consumers (containerboot, kube agents, sniproxy, etc.) listen on
+		// this signal and re-fetch peers/DNS via the LocalAPI if they need
+		// more than self info.
+		var selfChange *tailcfg.Node
+		if st.NetMap.SelfNode.Valid() {
+			selfChange = st.NetMap.SelfNode.AsStruct()
+		}
+		b.sendLocked(ipn.Notify{NetMap: st.NetMap, SelfChange: selfChange})
 
 		// The error here is unimportant as is the result.  This will recalculate the suggested exit node
 		// cache the value and push any changes to the IPN bus.