all: convert from []wgcfg.Endpoint to string

This eliminates a dependency on wgcfg.Endpoint,
as part of the effort to eliminate our wireguard-go fork.

Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>

wgengine/magicsock/legacy.go

@@ -567,24 +567,18 @@ func (as *addrSet) populatePeerStatus(ps *ipnstate.PeerStatus) {
 	}
 }
 
-func (a *addrSet) Addrs() []wgcfg.Endpoint {
-	var eps []wgcfg.Endpoint
+func (a *addrSet) Addrs() string {
+	var addrs []string
 	for _, addr := range a.addrs {
-		eps = append(eps, wgcfg.Endpoint{
-			Host: addr.IP.String(),
-			Port: uint16(addr.Port),
-		})
+		addrs = append(addrs, addr.String())
 	}
 
 	a.mu.Lock()
 	defer a.mu.Unlock()
 	if a.roamAddr != nil {
-		eps = append(eps, wgcfg.Endpoint{
-			Host: a.roamAddr.IP.String(),
-			Port: uint16(a.roamAddr.Port),
-		})
+		addrs = append(addrs, a.roamAddr.String())
 	}
-	return eps
+	return strings.Join(addrs, ",")
 }
 
 // Message types copied from wireguard-go/device/noise-protocol.go

wgengine/magicsock/magicsock.go

@@ -28,7 +28,6 @@ import (
 	"time"
 
 	"github.com/tailscale/wireguard-go/conn"
-	"github.com/tailscale/wireguard-go/wgcfg"
 	"go4.org/mem"
 	"golang.org/x/crypto/nacl/box"
 	"golang.org/x/time/rate"
@@ -2977,19 +2976,11 @@ func (de *discoEndpoint) String() string {
 	return fmt.Sprintf("magicsock.discoEndpoint{%v, %v}", de.publicKey.ShortString(), de.discoShort)
 }
 
-func (de *discoEndpoint) Addrs() []wgcfg.Endpoint {
+func (de *discoEndpoint) Addrs() string {
 	// This has to be the same string that was passed to
 	// CreateEndpoint, otherwise Reconfig will end up recreating
 	// Endpoints and losing state over time.
-	host, portStr, err := net.SplitHostPort(de.wgEndpointHostPort)
-	if err != nil {
-		panic(err)
-	}
-	port, err := strconv.ParseUint(portStr, 10, 16)
-	if err != nil {
-		panic(err)
-	}
-	return []wgcfg.Endpoint{{Host: host, Port: uint16(port)}}
+	return de.wgEndpointHostPort
 }
 
 func (de *discoEndpoint) ClearSrc()           {}

wgengine/magicsock/magicsock_test.go

@@ -483,12 +483,9 @@ func makeConfigs(t *testing.T, addrs []netaddr.IPPort) []wgcfg.Config {
 				continue
 			}
 			peer := wgcfg.Peer{
-				PublicKey:  privKeys[peerNum].Public(),
-				AllowedIPs: addresses[peerNum],
-				Endpoints: []wgcfg.Endpoint{{
-					Host: addr.IP.String(),
-					Port: addr.Port,
-				}},
+				PublicKey:           privKeys[peerNum].Public(),
+				AllowedIPs:          addresses[peerNum],
+				Endpoints:           addr.String(),
 				PersistentKeepalive: 25,
 			}
 			cfg.Peers = append(cfg.Peers, peer)
@@ -1140,12 +1137,12 @@ func testTwoDevicePing(t *testing.T, d *devices) {
 	})
 
 	// Add DERP relay.
-	derpEp := wgcfg.Endpoint{Host: "127.3.3.40", Port: 1}
+	derpEp := "127.3.3.40:1"
 	ep0 := cfgs[0].Peers[0].Endpoints
-	ep0 = append([]wgcfg.Endpoint{derpEp}, ep0...)
+	ep0 = derpEp + "," + ep0
 	cfgs[0].Peers[0].Endpoints = ep0
 	ep1 := cfgs[1].Peers[0].Endpoints
-	ep1 = append([]wgcfg.Endpoint{derpEp}, ep1...)
+	ep1 = derpEp + "," + ep1
 	cfgs[1].Peers[0].Endpoints = ep1
 	if err := m1.dev.Reconfig(&cfgs[0]); err != nil {
 		t.Fatal(err)
@@ -1161,8 +1158,8 @@ func testTwoDevicePing(t *testing.T, d *devices) {
 	})
 
 	// Disable real route.
-	cfgs[0].Peers[0].Endpoints = []wgcfg.Endpoint{derpEp}
-	cfgs[1].Peers[0].Endpoints = []wgcfg.Endpoint{derpEp}
+	cfgs[0].Peers[0].Endpoints = derpEp
+	cfgs[1].Peers[0].Endpoints = derpEp
 	if err := m1.dev.Reconfig(&cfgs[0]); err != nil {
 		t.Fatal(err)
 	}

wgengine/userspace.go

@@ -674,10 +674,15 @@ func isTrimmablePeer(p *wgcfg.Peer, numPeers int) bool {
 	if forceFullWireguardConfig(numPeers) {
 		return false
 	}
-	if len(p.Endpoints) != 1 {
+	if !isSingleEndpoint(p.Endpoints) {
 		return false
 	}
-	if !strings.HasSuffix(p.Endpoints[0].Host, ".disco.tailscale") {
+
+	host, _, err := net.SplitHostPort(p.Endpoints)
+	if err != nil {
+		return false
+	}
+	if !strings.HasSuffix(host, ".disco.tailscale") {
 		return false
 	}
 
@@ -741,11 +746,14 @@ func (e *userspaceEngine) isActiveSince(dk tailcfg.DiscoKey, ip netaddr.IP, t ti
 // Host of form "<64-hex-digits>.disco.tailscale". If invariant is violated,
 // we return the zero value.
 func discoKeyFromPeer(p *wgcfg.Peer) tailcfg.DiscoKey {
-	host := p.Endpoints[0].Host
-	if len(host) < 64 {
+	if len(p.Endpoints) < 64 {
 		return tailcfg.DiscoKey{}
 	}
-	k, err := key.NewPublicFromHexMem(mem.S(host[:64]))
+	host, rest := p.Endpoints[:64], p.Endpoints[64:]
+	if !strings.HasPrefix(rest, ".disco.tailscale") {
+		return tailcfg.DiscoKey{}
+	}
+	k, err := key.NewPublicFromHexMem(mem.S(host))
 	if err != nil {
 		return tailcfg.DiscoKey{}
 	}
@@ -946,21 +954,21 @@ func (e *userspaceEngine) Reconfig(cfg *wgcfg.Config, routerCfg *router.Config)
 	// and a second time with it.
 	discoChanged := make(map[key.Public]bool)
 	{
-		prevEP := make(map[key.Public]wgcfg.Endpoint)
+		prevEP := make(map[key.Public]string)
 		for i := range e.lastCfgFull.Peers {
-			if p := &e.lastCfgFull.Peers[i]; len(p.Endpoints) == 1 {
-				prevEP[key.Public(p.PublicKey)] = p.Endpoints[0]
+			if p := &e.lastCfgFull.Peers[i]; isSingleEndpoint(p.Endpoints) {
+				prevEP[key.Public(p.PublicKey)] = p.Endpoints
 			}
 		}
 		for i := range cfg.Peers {
 			p := &cfg.Peers[i]
-			if len(p.Endpoints) != 1 {
+			if !isSingleEndpoint(p.Endpoints) {
 				continue
 			}
 			pub := key.Public(p.PublicKey)
-			if old, ok := prevEP[pub]; ok && old != p.Endpoints[0] {
+			if old, ok := prevEP[pub]; ok && old != p.Endpoints {
 				discoChanged[pub] = true
-				e.logf("wgengine: Reconfig: %s changed from %s to %s", pub.ShortString(), &old, &p.Endpoints[0])
+				e.logf("wgengine: Reconfig: %s changed from %q to %q", pub.ShortString(), old, p.Endpoints)
 			}
 		}
 	}
@@ -1005,6 +1013,11 @@ func (e *userspaceEngine) Reconfig(cfg *wgcfg.Config, routerCfg *router.Config)
 	return nil
 }
 
+// isSingleEndpoint reports whether endpoints contains exactly one host:port pair.
+func isSingleEndpoint(s string) bool {
+	return s != "" && !strings.Contains(s, ",")
+}
+
 func (e *userspaceEngine) GetFilter() *filter.Filter {
 	return e.tundev.GetFilter()
 }

wgengine/userspace_test.go

@@ -103,12 +103,7 @@ func TestUserspaceEngineReconfig(t *testing.T) {
 					AllowedIPs: []netaddr.IPPrefix{
 						{IP: netaddr.IPv4(100, 100, 99, 1), Bits: 32},
 					},
-					Endpoints: []wgcfg.Endpoint{
-						{
-							Host: discoHex + ".disco.tailscale",
-							Port: 12345,
-						},
-					},
+					Endpoints: discoHex + ".disco.tailscale:12345",
 				},
 			},
 		}

wgengine/wgengine.go

@@ -36,7 +36,7 @@ type PeerStatus struct {
 // TODO(bradfitz): remove this, subset of ipnstate? Need to migrate users.
 type Status struct {
 	Peers      []PeerStatus
-	LocalAddrs []string // TODO(crawshaw): []wgcfg.Endpoint?
+	LocalAddrs []string // the set of possible endpoints for the magic conn
 	DERPs      int      // number of active DERP connections
 }