From 0ce4695e131c58a299a33e02cadba3374e5e4a4a Mon Sep 17 00:00:00 2001
From: Claire Wang <claire@tailscale.com>
Date: Wed, 30 Nov 2022 11:11:07 -0500
Subject: [PATCH] ipn/ipnlocal: Fill out self IP addresses in
 StatusWithoutPeers Fixes tailscale/tailscale#4311 Signed-off-by: Claire Wang
 <claire@tailscale.com>

---
 ipn/ipnlocal/local.go      | 56 +++++++++++++++++++-------------------
 ipn/ipnlocal/local_test.go | 41 ++++++++++++++++++++++++++++
 2 files changed, 69 insertions(+), 28 deletions(-)

diff --git a/ipn/ipnlocal/local.go b/ipn/ipnlocal/local.go
index 27095a85c..0afab3b87 100644
--- a/ipn/ipnlocal/local.go
+++ b/ipn/ipnlocal/local.go
@@ -570,6 +570,27 @@ func (b *LocalBackend) UpdateStatus(sb *ipnstate.StatusBuilder) {
 func (b *LocalBackend) updateStatus(sb *ipnstate.StatusBuilder, extraLocked func(*ipnstate.StatusBuilder)) {
 	b.mu.Lock()
 	defer b.mu.Unlock()
+	sb.MutateSelfStatus(func(ss *ipnstate.PeerStatus) {
+		ss.Online = health.GetInPollNetMap()
+		if b.netMap != nil {
+			ss.InNetworkMap = true
+			ss.HostName = b.netMap.Hostinfo.Hostname
+			ss.DNSName = b.netMap.Name
+			ss.UserID = b.netMap.User
+			if sn := b.netMap.SelfNode; sn != nil {
+				peerStatusFromNode(ss, sn)
+				if c := sn.Capabilities; len(c) > 0 {
+					ss.Capabilities = append([]string(nil), c...)
+				}
+			}
+		} else {
+			ss.HostName, _ = os.Hostname()
+		}
+		for _, pln := range b.peerAPIListeners {
+			ss.PeerAPIURL = append(ss.PeerAPIURL, pln.urlStr)
+		}
+	})
+	// MutateSelfStatus is called before MutateStatus, so that way the self node's tailscale ips can be assigned to ipn state's tailscale ips.
 	sb.MutateStatus(func(s *ipnstate.Status) {
 		s.Version = version.Long
 		s.BackendState = b.state.String()
@@ -599,6 +620,7 @@ func (b *LocalBackend) updateStatus(sb *ipnstate.StatusBuilder, extraLocked func
 			s.CurrentTailnet.MagicDNSSuffix = b.netMap.MagicDNSSuffix()
 			s.CurrentTailnet.MagicDNSEnabled = b.netMap.DNS.Proxied
 			s.CurrentTailnet.Name = b.netMap.Domain
+			s.TailscaleIPs = s.Self.TailscaleIPs
 			if prefs := b.pm.CurrentPrefs(); prefs.Valid() {
 				if !prefs.RouteAll() && b.netMap.AnyPeersAdvertiseRoutes() {
 					s.Health = append(s.Health, healthmsg.WarnAcceptRoutesOff)
@@ -619,29 +641,8 @@ func (b *LocalBackend) updateStatus(sb *ipnstate.StatusBuilder, extraLocked func
 			}
 		}
 	})
-	sb.MutateSelfStatus(func(ss *ipnstate.PeerStatus) {
-		ss.Online = health.GetInPollNetMap()
-		if b.netMap != nil {
-			ss.InNetworkMap = true
-			ss.HostName = b.netMap.Hostinfo.Hostname
-			ss.DNSName = b.netMap.Name
-			ss.UserID = b.netMap.User
-			if sn := b.netMap.SelfNode; sn != nil {
-				peerStatusFromNode(ss, sn)
-				if c := sn.Capabilities; len(c) > 0 {
-					ss.Capabilities = append([]string(nil), c...)
-				}
-			}
-		} else {
-			ss.HostName, _ = os.Hostname()
-		}
-		for _, pln := range b.peerAPIListeners {
-			ss.PeerAPIURL = append(ss.PeerAPIURL, pln.urlStr)
-		}
-	})
 	// TODO: hostinfo, and its networkinfo
 	// TODO: EngineStatus copy (and deprecate it?)
-
 	if extraLocked != nil {
 		extraLocked(sb)
 	}
@@ -660,16 +661,9 @@ func (b *LocalBackend) populatePeerStatusLocked(sb *ipnstate.StatusBuilder) {
 		if p.LastSeen != nil {
 			lastSeen = *p.LastSeen
 		}
-		var tailscaleIPs = make([]netip.Addr, 0, len(p.Addresses))
-		for _, addr := range p.Addresses {
-			if addr.IsSingleIP() && tsaddr.IsTailscaleIP(addr.Addr()) {
-				tailscaleIPs = append(tailscaleIPs, addr.Addr())
-			}
-		}
 		ps := &ipnstate.PeerStatus{
 			InNetworkMap: true,
 			UserID:       p.User,
-			TailscaleIPs: tailscaleIPs,
 			HostName:     p.Hostinfo.Hostname(),
 			DNSName:      p.Name,
 			OS:           p.Hostinfo.OS(),
@@ -707,6 +701,12 @@ func peerStatusFromNode(ps *ipnstate.PeerStatus, n *tailcfg.Node) {
 		v := views.IPPrefixSliceOf(n.PrimaryRoutes)
 		ps.PrimaryRoutes = &v
 	}
+	ps.TailscaleIPs = make([]netip.Addr, 0, len(n.Addresses))
+	for _, addr := range n.Addresses {
+		if addr.IsSingleIP() && tsaddr.IsTailscaleIP(addr.Addr()) {
+			ps.TailscaleIPs = append(ps.TailscaleIPs, addr.Addr())
+		}
+	}
 }
 
 // WhoIs reports the node and user who owns the node with the given IP:port.
diff --git a/ipn/ipnlocal/local_test.go b/ipn/ipnlocal/local_test.go
index 6d46491bc..4c462f75d 100644
--- a/ipn/ipnlocal/local_test.go
+++ b/ipn/ipnlocal/local_test.go
@@ -14,11 +14,13 @@
 	"time"
 
 	"go4.org/netipx"
+	"tailscale.com/control/controlclient"
 	"tailscale.com/ipn"
 	"tailscale.com/ipn/store/mem"
 	"tailscale.com/net/interfaces"
 	"tailscale.com/net/tsaddr"
 	"tailscale.com/tailcfg"
+	"tailscale.com/tstest"
 	"tailscale.com/types/logger"
 	"tailscale.com/types/netmap"
 	"tailscale.com/wgengine"
@@ -744,6 +746,45 @@ func TestPacketFilterPermitsUnlockedNodes(t *testing.T) {
 
 }
 
+func TestStatusWithoutPeers(t *testing.T) {
+	logf := tstest.WhileTestRunningLogger(t)
+	store := new(testStateStorage)
+	e, err := wgengine.NewFakeUserspaceEngine(logf, 0)
+	if err != nil {
+		t.Fatalf("NewFakeUserspaceEngine: %v", err)
+	}
+	t.Cleanup(e.Close)
+
+	b, err := NewLocalBackend(logf, "logid", store, "", nil, e, 0)
+	if err != nil {
+		t.Fatalf("NewLocalBackend: %v", err)
+	}
+	var cc *mockControl
+	b.SetControlClientGetterForTesting(func(opts controlclient.Options) (controlclient.Client, error) {
+		cc = newClient(t, opts)
+
+		t.Logf("ccGen: new mockControl.")
+		cc.called("New")
+		return cc, nil
+	})
+	b.Start(ipn.Options{})
+	b.Login(nil)
+	cc.send(nil, "", false, &netmap.NetworkMap{
+		MachineStatus: tailcfg.MachineAuthorized,
+		Addresses:     ipps("100.101.101.101"),
+		SelfNode: &tailcfg.Node{
+			Addresses: ipps("100.101.101.101"),
+		},
+	})
+	got := b.StatusWithoutPeers()
+	if got.TailscaleIPs == nil {
+		t.Errorf("got nil, expected TailscaleIPs value to not be nil")
+	}
+	if !reflect.DeepEqual(got.TailscaleIPs, got.Self.TailscaleIPs) {
+		t.Errorf("got %v, expected %v", got.TailscaleIPs, got.Self.TailscaleIPs)
+	}
+}
+
 // legacyBackend was the interface between Tailscale frontends
 // (e.g. cmd/tailscale, iOS/MacOS/Windows GUIs) and the tailscale
 // backend (e.g. cmd/tailscaled) running on the same machine.