ipn/ipnstate: remove old deprecated TailAddr IPv4-only field

It's been a bunch of releases now since the TailscaleIPs slice
replacement was added.

Change-Id: I3bd80e1466b3d9e4a4ac5bedba8b4d3d3e430a03
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>

ipn/ipnlocal/local.go

@@ -417,16 +417,9 @@ func (b *LocalBackend) populatePeerStatusLocked(sb *ipnstate.StatusBuilder) {
 		if p.LastSeen != nil {
 			lastSeen = *p.LastSeen
 		}
-		var tailAddr4 string
 		var tailscaleIPs = make([]netaddr.IP, 0, len(p.Addresses))
 		for _, addr := range p.Addresses {
 			if addr.IsSingleIP() && tsaddr.IsTailscaleIP(addr.IP()) {
-				if addr.IP().Is4() && tailAddr4 == "" {
-					// The peer struct previously only allowed a single
-					// Tailscale IP address. For compatibility for a few releases starting
-					// with 1.8, keep it pulled out as IPv4-only for a bit.
-					tailAddr4 = addr.IP().String()
-				}
 				tailscaleIPs = append(tailscaleIPs, addr.IP())
 			}
 		}
@@ -437,7 +430,6 @@ func (b *LocalBackend) populatePeerStatusLocked(sb *ipnstate.StatusBuilder) {
 			InNetworkMap:   true,
 			ID:             p.StableID,
 			UserID:         p.User,
-			TailAddrDeprecated: tailAddr4,
 			TailscaleIPs:   tailscaleIPs,
 			HostName:       p.Hostinfo.Hostname,
 			DNSName:        p.Name,

ipn/ipnstate/ipnstate.go

@@ -88,7 +88,6 @@ type PeerStatus struct {
 	OS        string // HostInfo.OS
 	UserID    tailcfg.UserID
 
-	TailAddrDeprecated string       `json:"TailAddr"` // Tailscale IP
 	TailscaleIPs []netaddr.IP // Tailscale IP(s) assigned to this node
 
 	// Endpoints:
@@ -244,9 +243,6 @@ func (sb *StatusBuilder) AddPeer(peer key.NodePublic, st *PeerStatus) {
 	if v := st.UserID; v != 0 {
 		e.UserID = v
 	}
-	if v := st.TailAddrDeprecated; v != "" {
-		e.TailAddrDeprecated = v
-	}
 	if v := st.TailscaleIPs; v != nil {
 		e.TailscaleIPs = v
 	}

wgengine/magicsock/magicsock.go

@@ -3097,7 +3097,6 @@ func (c *Conn) UpdateStatus(sb *ipnstate.StatusBuilder) {
 	c.mu.Lock()
 	defer c.mu.Unlock()
 
-	var tailAddr4 string
 	var tailscaleIPs []netaddr.IP
 	if c.netMap != nil {
 		tailscaleIPs = make([]netaddr.IP, 0, len(c.netMap.Addresses))
@@ -3106,13 +3105,6 @@ func (c *Conn) UpdateStatus(sb *ipnstate.StatusBuilder) {
 				continue
 			}
 			sb.AddTailscaleIP(addr.IP())
-			// TailAddr previously only allowed for a
-			// single Tailscale IP. For compatibility for
-			// a couple releases starting with 1.8, keep
-			// that field pulled out separately.
-			if addr.IP().Is4() {
-				tailAddr4 = addr.IP().String()
-			}
 			tailscaleIPs = append(tailscaleIPs, addr.IP())
 		}
 	}
@@ -3135,7 +3127,6 @@ func (c *Conn) UpdateStatus(sb *ipnstate.StatusBuilder) {
 			}
 		}
 		ss.TailscaleIPs = tailscaleIPs
-		ss.TailAddrDeprecated = tailAddr4
 	})
 
 	c.peerMap.forEachEndpoint(func(ep *endpoint) {